Refactor indentation for consistent style across codebase.

Refactor syntax highlighting infrastructure and related classes.
- Moved all language highlighter implementations (`CppHighlighter`, `GoHighlighter`, `JsonHighlighter`, etc.), the engine, and registry to `syntax/`.
2025-12-02 01:37:44 -08:00 · 2025-12-02 01:36:26 -08:00 · 2025-12-01 19:04:37 -08:00 · 2025-12-01 18:37:01 -08:00 · 2025-12-01 18:20:36 -08:00 · 2025-12-01 16:47:16 -08:00
67 changed files with 7318 additions and 2110 deletions
--- a/.idea/workspace.xml
+++ b/.idea/workspace.xml
@@ -1,369 +0,0 @@
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--- a/Buffer.cc
+++ b/Buffer.cc
@@ -6,6 +6,9 @@
 #include "Buffer.h"
 #include "UndoSystem.h"
 #include "UndoTree.h"
 // For reconstructing highlighter state on copies
 #include "syntax/HighlighterRegistry.h"
 #include "syntax/NullHighlighter.h"
 Buffer::Buffer()
@@ -40,9 +43,32 @@ Buffer::Buffer(const Buffer &other)
 	mark_set_       = other.mark_set_;
 	mark_curx_      = other.mark_curx_;
 	mark_cury_      = other.mark_cury_;
 	// Copy syntax/highlighting flags
 	version_        = other.version_;
 	syntax_enabled_ = other.syntax_enabled_;
 	filetype_       = other.filetype_;
 	// Fresh undo system for the copy
 	undo_tree_ = std::make_unique<UndoTree>();
 	undo_sys_  = std::make_unique<UndoSystem>(*this, *undo_tree_);
 	// Recreate a highlighter engine for this copy based on filetype/syntax state
 	if (syntax_enabled_) {
 		// Allocate engine and install an appropriate highlighter
 		highlighter_ = std::make_unique<kte::HighlighterEngine>();
 		if (!filetype_.empty()) {
 			auto hl = kte::HighlighterRegistry::CreateFor(filetype_);
 			if (hl) {
 				highlighter_->SetHighlighter(std::move(hl));
 			} else {
 				// Unsupported filetype -> NullHighlighter keeps syntax pipeline active
 				highlighter_->SetHighlighter(std::make_unique<kte::NullHighlighter>());
 			}
 		} else {
 			// No filetype -> keep syntax enabled but use NullHighlighter
 			highlighter_->SetHighlighter(std::make_unique<kte::NullHighlighter>());
 		}
 		// Fresh engine has empty caches; nothing to invalidate
 	}
 }
@@ -65,9 +91,28 @@ Buffer::operator=(const Buffer &other)
 	mark_set_       = other.mark_set_;
 	mark_curx_      = other.mark_curx_;
 	mark_cury_      = other.mark_cury_;
 	version_        = other.version_;
 	syntax_enabled_ = other.syntax_enabled_;
 	filetype_       = other.filetype_;
 	// Recreate undo system for this instance
 	undo_tree_ = std::make_unique<UndoTree>();
 	undo_sys_  = std::make_unique<UndoSystem>(*this, *undo_tree_);
 	// Recreate highlighter engine consistent with syntax settings
 	highlighter_.reset();
 	if (syntax_enabled_) {
 		highlighter_ = std::make_unique<kte::HighlighterEngine>();
 		if (!filetype_.empty()) {
 			auto hl = kte::HighlighterRegistry::CreateFor(filetype_);
 			if (hl) {
 				highlighter_->SetHighlighter(std::move(hl));
 			} else {
 				highlighter_->SetHighlighter(std::make_unique<kte::NullHighlighter>());
 			}
 		} else {
 			highlighter_->SetHighlighter(std::make_unique<kte::NullHighlighter>());
 		}
 	}
 	return *this;
 }
@@ -91,6 +136,11 @@ Buffer::Buffer(Buffer &&other) noexcept
 	  undo_tree_(std::move(other.undo_tree_)),
 	  undo_sys_(std::move(other.undo_sys_))
 {
 	// Move syntax/highlighting state
 	version_        = other.version_;
 	syntax_enabled_ = other.syntax_enabled_;
 	filetype_       = std::move(other.filetype_);
 	highlighter_    = std::move(other.highlighter_);
 	// Update UndoSystem's buffer reference to point to this object
 	if (undo_sys_) {
 		undo_sys_->UpdateBufferReference(*this);
@@ -122,6 +172,12 @@ Buffer::operator=(Buffer &&other) noexcept
 	undo_tree_      = std::move(other.undo_tree_);
 	undo_sys_       = std::move(other.undo_sys_);
 	// Move syntax/highlighting state
 	version_        = other.version_;
 	syntax_enabled_ = other.syntax_enabled_;
 	filetype_       = std::move(other.filetype_);
 	highlighter_    = std::move(other.highlighter_);
 	// Update UndoSystem's buffer reference to point to this object
 	if (undo_sys_) {
 		undo_sys_->UpdateBufferReference(*this);
--- a/Buffer.h
+++ b/Buffer.h
@@ -12,6 +12,10 @@
 #include "AppendBuffer.h"
 #include "UndoSystem.h"
 #include <cstdint>
 #include <memory>
 #include "syntax/HighlighterEngine.h"
 #include "Highlight.h"
 class Buffer {
@@ -262,6 +266,7 @@ public:
 		return filename_;
 	}
 	// Set a virtual (non file-backed) display name for this buffer, e.g. "+HELP+"
 	// This does not mark the buffer as file-backed.
 	void SetVirtualName(const std::string &name)
@@ -282,17 +287,20 @@ public:
 		return dirty_;
 	}
 	// Read-only flag
 	[[nodiscard]] bool IsReadOnly() const
 	{
 		return read_only_;
 	}
 	void SetReadOnly(bool ro)
 	{
 		read_only_ = ro;
 	}
 	void ToggleReadOnly()
 	{
 		read_only_ = !read_only_;
@@ -322,6 +330,12 @@ public:
 	void SetDirty(bool d)
 	{
 		dirty_ = d;
 		if (d) {
 			++version_;
 			if (highlighter_) {
 				highlighter_->InvalidateFrom(0);
 			}
 		}
 	}
@@ -360,6 +374,56 @@ public:
 	[[nodiscard]] std::string AsString() const;
 	// Syntax highlighting integration (per-buffer)
 	[[nodiscard]] std::uint64_t Version() const
 	{
 		return version_;
 	}
 	void SetSyntaxEnabled(bool on)
 	{
 		syntax_enabled_ = on;
 	}
 	[[nodiscard]] bool SyntaxEnabled() const
 	{
 		return syntax_enabled_;
 	}
 	void SetFiletype(const std::string &ft)
 	{
 		filetype_ = ft;
 	}
 	[[nodiscard]] const std::string &Filetype() const
 	{
 		return filetype_;
 	}
 	kte::HighlighterEngine *Highlighter()
 	{
 		return highlighter_.get();
 	}
 	const kte::HighlighterEngine *Highlighter() const
 	{
 		return highlighter_.get();
 	}
 	void EnsureHighlighter()
 	{
 		if (!highlighter_)
 			highlighter_ = std::make_unique<kte::HighlighterEngine>();
 	}
 	// Raw, low-level editing APIs used by UndoSystem apply().
 	// These must NOT trigger undo recording. They also do not move the cursor.
 	void insert_text(int row, int col, std::string_view text);
@@ -396,6 +460,12 @@ private:
 	// Per-buffer undo state
 	std::unique_ptr<struct UndoTree> undo_tree_;
 	std::unique_ptr<UndoSystem> undo_sys_;
 	// Syntax/highlighting state
 	std::uint64_t version_ = 0; // increment on edits
 	bool syntax_enabled_   = true;
 	std::string filetype_;
 	std::unique_ptr<kte::HighlighterEngine> highlighter_;
 };
 #endif // KTE_BUFFER_H
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -4,7 +4,7 @@ project(kte)
 include(GNUInstallDirs)
 set(CMAKE_CXX_STANDARD 17)
-set(KTE_VERSION "1.1.0")
+set(KTE_VERSION "1.2.1")
 # Default to terminal-only build to avoid SDL/OpenGL dependency by default.
 # Enable with -DBUILD_GUI=ON when SDL2/OpenGL/Freetype are available.
@@ -13,6 +13,7 @@ set(BUILD_TESTS OFF CACHE BOOL "Enable building test programs.")
 option(KTE_USE_PIECE_TABLE "Use PieceTable instead of GapBuffer implementation" ON)
 set(KTE_FONT_SIZE "18.0" CACHE STRING "Default font size for GUI")
 option(KTE_UNDO_DEBUG "Enable undo instrumentation logs" OFF)
 option(KTE_ENABLE_TREESITTER "Enable optional Tree-sitter highlighter adapter" OFF)
 if (CMAKE_HOST_UNIX)
 	message(STATUS "Build system is POSIX.")
@@ -37,6 +38,9 @@ else ()
 endif ()
 add_compile_definitions(KGE_PLATFORM=${CMAKE_HOST_SYSTEM_NAME})
 add_compile_definitions(KTE_VERSION_STR="v${KTE_VERSION}")
 if (KTE_ENABLE_TREESITTER)
 	add_compile_definitions(KTE_ENABLE_TREESITTER)
 endif ()
 message(STATUS "Build system: ${CMAKE_HOST_SYSTEM_NAME}")
@@ -50,6 +54,29 @@ set(CURSES_NEED_WIDE)
 find_package(Curses REQUIRED)
 include_directories(${CURSES_INCLUDE_DIR})
 set(SYNTAX_SOURCES
 	syntax/GoHighlighter.cc
 	syntax/CppHighlighter.cc
 	syntax/JsonHighlighter.cc
 	syntax/ErlangHighlighter.cc
 	syntax/MarkdownHighlighter.cc
 	syntax/TreeSitterHighlighter.cc
 	syntax/LispHighlighter.cc
 	syntax/HighlighterEngine.cc
 	syntax/RustHighlighter.cc
 	syntax/HighlighterRegistry.cc
 	syntax/SqlHighlighter.cc
 	syntax/NullHighlighter.cc
 	syntax/ForthHighlighter.cc
 	syntax/PythonHighlighter.cc
 	syntax/ShellHighlighter.cc
 )
 if (KTE_ENABLE_TREESITTER)
 	list(APPEND SYNTAX_SOURCES
 		TreeSitterHighlighter.cc)
 endif ()
 set(COMMON_SOURCES
 	GapBuffer.cc
 	PieceTable.cc
@@ -67,6 +94,41 @@ set(COMMON_SOURCES
 	UndoNode.cc
 	UndoTree.cc
 	UndoSystem.cc
 	${SYNTAX_SOURCES}
 )
 set(SYNTAX_HEADERS
 	syntax/GoHighlighter.h
 	syntax/HighlighterEngine.h
 	syntax/ShellHighlighter.h
 	syntax/MarkdownHighlighter.h
 	syntax/LispHighlighter.h
 	syntax/SqlHighlighter.h
 	syntax/ForthHighlighter.h
 	syntax/JsonHighlighter.h
 	syntax/TreeSitterHighlighter.h
 	syntax/NullHighlighter.h
 	syntax/CppHighlighter.h
 	syntax/ErlangHighlighter.h
 	syntax/LanguageHighlighter.h
 	syntax/RustHighlighter.h
 	syntax/PythonHighlighter.h
 )
 if (KTE_ENABLE_TREESITTER)
 	list(APPEND THEME_HEADERS
 		TreeSitterHighlighter.h)
 endif ()
 set(THEME_HEADERS
 	themes/ThemeHelpers.h
 	themes/EInk.h
 	themes/Gruvbox.h
 	themes/Solarized.h
 	themes/Plan9.h
 	themes/Nord.h
 )
 set(COMMON_HEADERS
@@ -90,6 +152,10 @@ set(COMMON_HEADERS
 	UndoNode.h
 	UndoTree.h
 	UndoSystem.h
 	Highlight.h
 	${SYNTAX_HEADERS}
 	${THEME_HEADERS}
 )
 # kte (terminal-first) executable
@@ -108,6 +174,18 @@ endif ()
 target_link_libraries(kte ${CURSES_LIBRARIES})
 if (KTE_ENABLE_TREESITTER)
 	# Users can provide their own tree-sitter include/lib via cache variables
 	set(TREESITTER_INCLUDE_DIR "" CACHE PATH "Path to tree-sitter include directory")
 	set(TREESITTER_LIBRARY "" CACHE FILEPATH "Path to tree-sitter library (.a/.dylib)")
 	if (TREESITTER_INCLUDE_DIR)
 		target_include_directories(kte PRIVATE ${TREESITTER_INCLUDE_DIR})
 	endif ()
 	if (TREESITTER_LIBRARY)
 		target_link_libraries(kte ${TREESITTER_LIBRARY})
 	endif ()
 endif ()
 install(TARGETS kte
 	RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR}
 )
@@ -133,6 +211,14 @@ if (BUILD_TESTS)
 	target_link_libraries(test_undo ${CURSES_LIBRARIES})
 	if (KTE_ENABLE_TREESITTER)
 		if (TREESITTER_INCLUDE_DIR)
 			target_include_directories(test_undo PRIVATE ${TREESITTER_INCLUDE_DIR})
 		endif ()
 		if (TREESITTER_LIBRARY)
 			target_link_libraries(test_undo ${TREESITTER_LIBRARY})
 		endif ()
 	endif ()
 endif ()
 if (${BUILD_GUI})
--- a/Command.cc
+++ b/Command.cc
@@ -4,12 +4,21 @@
 #include <regex>
 #include <fstream>
 #include <sstream>
 #include <cctype>
 #include "Command.h"
 #include "syntax/HighlighterRegistry.h"
 #include "syntax/NullHighlighter.h"
 #include "Editor.h"
 #include "Buffer.h"
 #include "UndoSystem.h"
 #include "HelpText.h"
 #include "syntax/LanguageHighlighter.h"
 #include "syntax/HighlighterEngine.h"
 #include "syntax/CppHighlighter.h"
 #ifdef KTE_BUILD_GUI
 #include "GUITheme.h"
 #endif
 // Keep buffer viewport offsets so that the cursor stays within the visible
@@ -87,8 +96,10 @@ ensure_at_least_one_line(Buffer &buf)
 	}
 }
 // Determine if a command mutates the buffer contents (text edits)
-static bool is_mutating_command(CommandId id)
+static bool
 is_mutating_command(CommandId id)
 {
 	switch (id) {
 	case CommandId::InsertText:
@@ -723,6 +734,21 @@ cmd_kprefix(CommandContext &ctx)
 }
 // Start generic command prompt (": ")
 static bool
 cmd_command_prompt_start(const CommandContext &ctx)
 {
 	// Close any pending edit batch before entering prompt
 	if (Buffer *b = ctx.editor.CurrentBuffer()) {
 		if (auto *u = b->Undo())
 			u->commit();
 	}
 	ctx.editor.StartPrompt(Editor::PromptKind::Command, "", "");
 	ctx.editor.SetStatus(": ");
 	return true;
 }
 static bool
 cmd_unknown_kcommand(CommandContext &ctx)
 {
@@ -737,8 +763,272 @@ cmd_unknown_kcommand(CommandContext &ctx)
 }
 // --- Syntax highlighting commands ---
 static void
 apply_filetype(Buffer &buf, const std::string &ft)
 {
 	buf.EnsureHighlighter();
 	auto *eng = buf.Highlighter();
 	if (!eng)
 		return;
 	std::string val = ft;
 	// trim + lower
 	auto trim = [](const std::string &s) {
 		std::string r = s;
 		auto notsp    = [](int ch) {
 			return !std::isspace(ch);
 		};
 		r.erase(r.begin(), std::find_if(r.begin(), r.end(), notsp));
 		r.erase(std::find_if(r.rbegin(), r.rend(), notsp).base(), r.end());
 		return r;
 	};
 	val = trim(val);
 	for (auto &ch: val)
 		ch = static_cast<char>(std::tolower(static_cast<unsigned char>(ch)));
 	if (val == "off") {
 		eng->SetHighlighter(nullptr);
 		buf.SetFiletype("");
 		buf.SetSyntaxEnabled(false);
 		return;
 	}
 	if (val.empty()) {
 		// Empty means unknown/unspecified -> use NullHighlighter but keep syntax enabled
 		buf.SetFiletype("");
 		buf.SetSyntaxEnabled(true);
 		eng->SetHighlighter(std::make_unique<kte::NullHighlighter>());
 		eng->InvalidateFrom(0);
 		return;
 	}
 	// Normalize and create via registry
 	std::string norm = kte::HighlighterRegistry::Normalize(val);
 	auto hl          = kte::HighlighterRegistry::CreateFor(norm);
 	if (hl) {
 		eng->SetHighlighter(std::move(hl));
 		buf.SetFiletype(norm);
 		buf.SetSyntaxEnabled(true);
 		eng->InvalidateFrom(0);
 	} else {
 		// Unknown -> install NullHighlighter and keep syntax enabled
 		eng->SetHighlighter(std::make_unique<kte::NullHighlighter>());
 		buf.SetFiletype(val); // record what user asked even if unsupported
 		buf.SetSyntaxEnabled(true);
 		eng->InvalidateFrom(0);
 	}
 }
 static bool
-cmd_find_start(CommandContext &ctx)
+cmd_syntax(CommandContext &ctx)
 {
 	Buffer *b = ctx.editor.CurrentBuffer();
 	if (!b) {
 		ctx.editor.SetStatus("No buffer");
 		return true;
 	}
 	std::string arg = ctx.arg;
 	// trim
 	auto trim = [](std::string &s) {
 		auto notsp = [](int ch) {
 			return !std::isspace(ch);
 		};
 		s.erase(s.begin(), std::find_if(s.begin(), s.end(), notsp));
 		s.erase(std::find_if(s.rbegin(), s.rend(), notsp).base(), s.end());
 	};
 	trim(arg);
 	if (arg == "on") {
 		b->SetSyntaxEnabled(true);
 		// If no highlighter but filetype is cpp by extension, set it
 		if (!b->Highlighter() || !b->Highlighter()->HasHighlighter()) {
 			apply_filetype(*b, b->Filetype().empty() ? std::string("cpp") : b->Filetype());
 		}
 		ctx.editor.SetStatus("syntax: on");
 	} else if (arg == "off") {
 		b->SetSyntaxEnabled(false);
 		ctx.editor.SetStatus("syntax: off");
 	} else if (arg == "reload") {
 		if (auto *eng = b->Highlighter())
 			eng->InvalidateFrom(0);
 		ctx.editor.SetStatus("syntax: reloaded");
 	} else {
 		ctx.editor.SetStatus("usage: :syntax on|off|reload");
 	}
 	return true;
 }
 static bool
 cmd_set_option(CommandContext &ctx)
 {
 	Buffer *b = ctx.editor.CurrentBuffer();
 	if (!b) {
 		ctx.editor.SetStatus("No buffer");
 		return true;
 	}
 	// Expect key=value
 	auto eq = ctx.arg.find('=');
 	if (eq == std::string::npos) {
 		ctx.editor.SetStatus("usage: :set key=value");
 		return true;
 	}
 	std::string key = ctx.arg.substr(0, eq);
 	std::string val = ctx.arg.substr(eq + 1);
 	// trim
 	auto trim = [](std::string &s) {
 		auto notsp = [](int ch) {
 			return !std::isspace(ch);
 		};
 		s.erase(s.begin(), std::find_if(s.begin(), s.end(), notsp));
 		s.erase(std::find_if(s.rbegin(), s.rend(), notsp).base(), s.end());
 	};
 	trim(key);
 	trim(val);
 	// lower-case value for filetype
 	for (auto &ch: val)
 		ch = static_cast<char>(std::tolower(static_cast<unsigned char>(ch)));
 	if (key == "filetype") {
 		apply_filetype(*b, val);
 		if (b->SyntaxEnabled())
 			ctx.editor.SetStatus(
 				std::string("filetype: ") + (b->Filetype().empty() ? "off" : b->Filetype()));
 		else
 			ctx.editor.SetStatus("filetype: off");
 		return true;
 	}
 	ctx.editor.SetStatus("unknown option: " + key);
 	return true;
 }
 // GUI theme cycling commands (available in GUI build; show message otherwise)
 #ifdef KTE_BUILD_GUI
 static bool
 cmd_theme_next(CommandContext &ctx)
 {
 	auto id = kte::NextTheme();
 	ctx.editor.SetStatus(std::string("Theme: ") + kte::ThemeName(id));
 	return true;
 }
 static bool
 cmd_theme_prev(CommandContext &ctx)
 {
 	auto id = kte::PrevTheme();
 	ctx.editor.SetStatus(std::string("Theme: ") + kte::ThemeName(id));
 	return true;
 }
 #else
 static bool
 cmd_theme_next(CommandContext &ctx)
 {
 	ctx.editor.SetStatus("Theme switching only available in GUI build");
 	return true;
 }
 static bool
 cmd_theme_prev(CommandContext &ctx)
 {
 	ctx.editor.SetStatus("Theme switching only available in GUI build");
 	return true;
 }
 #endif
 // Theme set by name command
 #ifdef KTE_BUILD_GUI
 static bool
 cmd_theme_set_by_name(const CommandContext &ctx)
 {
 	std::string name = ctx.arg;
 	// trim spaces
 	auto ltrim = [](std::string &s) {
 		s.erase(s.begin(), std::find_if(s.begin(), s.end(), [](unsigned char ch) {
 			return !std::isspace(ch);
 		}));
 	};
 	auto rtrim = [](std::string &s) {
 		s.erase(std::find_if(s.rbegin(), s.rend(), [](unsigned char ch) {
 			return !std::isspace(ch);
 		}).base(), s.end());
 	};
 	ltrim(name);
 	rtrim(name);
 	if (name.empty()) {
 		ctx.editor.SetStatus("theme: missing name");
 		return true;
 	}
 	if (kte::ApplyThemeByName(name)) {
 		ctx.editor.SetStatus(
 			std::string("Theme: ") + name + std::string(" (bg: ") + kte::BackgroundModeName() + ")");
 	} else {
 		// Build list of available themes
 		const auto &reg = kte::ThemeRegistry();
 		std::string avail;
 		for (size_t i = 0; i < reg.size(); ++i) {
 			if (i)
 				avail += ", ";
 			avail += reg[i]->Name();
 		}
 		ctx.editor.SetStatus(std::string("Unknown theme; available: ") + avail);
 	}
 	return true;
 }
 #else
 static bool
 cmd_theme_set_by_name(CommandContext &ctx)
 {
 	(void) ctx;
 	// No-op in terminal build
 	return true;
 }
 #endif
 // Background set command (GUI)
 #ifdef KTE_BUILD_GUI
 static bool
 cmd_background_set(const CommandContext &ctx)
 {
 	std::string mode = ctx.arg;
 	// trim
 	auto ltrim = [](std::string &s) {
 		s.erase(s.begin(), std::find_if(s.begin(), s.end(), [](unsigned char ch) {
 			return !std::isspace(ch);
 		}));
 	};
 	auto rtrim = [](std::string &s) {
 		s.erase(std::find_if(s.rbegin(), s.rend(), [](unsigned char ch) {
 			return !std::isspace(ch);
 		}).base(), s.end());
 	};
 	ltrim(mode);
 	rtrim(mode);
 	std::transform(mode.begin(), mode.end(), mode.begin(), [](unsigned char c) {
 		return (char) std::tolower(c);
 	});
 	if (mode != "light" && mode != "dark") {
 		ctx.editor.SetStatus("background: expected 'light' or 'dark'");
 		return true;
 	}
 	kte::SetBackgroundMode(mode == "light" ? kte::BackgroundMode::Light : kte::BackgroundMode::Dark);
 	// Re-apply current theme to reflect background change
 	kte::ApplyThemeByName(kte::CurrentThemeName());
 	ctx.editor.SetStatus(std::string("Background: ") + mode + std::string("; Theme: ") + kte::CurrentThemeName());
 	return true;
 }
 #else
 static bool
 cmd_background_set(CommandContext &ctx)
 {
 	(void) ctx;
 	return true;
 }
 #endif
 static bool
 cmd_find_start(const CommandContext &ctx)
 {
 	Buffer *buf = ctx.editor.CurrentBuffer();
 	if (!buf) {
@@ -761,7 +1051,7 @@ cmd_find_start(CommandContext &ctx)
 static bool
-cmd_regex_find_start(CommandContext &ctx)
+cmd_regex_find_start(const CommandContext &ctx)
 {
 	Buffer *buf = ctx.editor.CurrentBuffer();
 	if (!buf) {
@@ -784,7 +1074,7 @@ cmd_regex_find_start(CommandContext &ctx)
 static bool
-cmd_search_replace_start(CommandContext &ctx)
+cmd_search_replace_start(const CommandContext &ctx)
 {
 	Buffer *buf = ctx.editor.CurrentBuffer();
 	if (!buf) {
@@ -808,7 +1098,7 @@ cmd_search_replace_start(CommandContext &ctx)
 static bool
-cmd_regex_replace_start(CommandContext &ctx)
+cmd_regex_replace_start(const CommandContext &ctx)
 {
 	Buffer *buf = ctx.editor.CurrentBuffer();
 	if (!buf) {
@@ -832,7 +1122,7 @@ cmd_regex_replace_start(CommandContext &ctx)
 static bool
-cmd_open_file_start(CommandContext &ctx)
+cmd_open_file_start(const CommandContext &ctx)
 {
 	// Start a generic prompt to read a path
 	ctx.editor.StartPrompt(Editor::PromptKind::OpenFile, "Open", "");
@@ -843,7 +1133,7 @@ cmd_open_file_start(CommandContext &ctx)
 // GUI: toggle visual file picker (no-op in terminal; renderer will consume flag)
 static bool
-cmd_visual_file_picker_toggle(CommandContext &ctx)
+cmd_visual_file_picker_toggle(const CommandContext &ctx)
 {
 	// Toggle visibility
 	bool show = !ctx.editor.FilePickerVisible();
@@ -866,7 +1156,7 @@ cmd_visual_file_picker_toggle(CommandContext &ctx)
 static bool
-cmd_jump_to_line_start(CommandContext &ctx)
+cmd_jump_to_line_start(const CommandContext &ctx)
 {
 	// Start a prompt to read a 1-based line number and jump there (clamped)
 	ctx.editor.StartPrompt(Editor::PromptKind::GotoLine, "Goto", "");
@@ -877,7 +1167,7 @@ cmd_jump_to_line_start(CommandContext &ctx)
 // --- Buffers: switch/next/prev/close ---
 static bool
-cmd_buffer_switch_start(CommandContext &ctx)
+cmd_buffer_switch_start(const CommandContext &ctx)
 {
 	// If only one (or zero) buffer is open, do nothing per spec
 	if (ctx.editor.BufferCount() <= 1) {
@@ -895,7 +1185,7 @@ buffer_display_name(const Buffer &b)
 {
 	if (!b.Filename().empty())
 		return b.Filename();
-	return std::string("<untitled>");
+	return {"<untitled>"};
 }
@@ -904,7 +1194,7 @@ buffer_basename(const Buffer &b)
 {
 	const std::string &p = b.Filename();
 	if (p.empty())
-		return std::string("<untitled>");
+		return {"<untitled>"};
 	auto pos = p.find_last_of("/\\");
 	if (pos == std::string::npos)
 		return p;
@@ -913,7 +1203,7 @@ buffer_basename(const Buffer &b)
 static bool
-cmd_buffer_next(CommandContext &ctx)
+cmd_buffer_next(const CommandContext &ctx)
 {
 	const auto cnt = ctx.editor.BufferCount();
 	if (cnt <= 1) {
@@ -930,7 +1220,7 @@ cmd_buffer_next(CommandContext &ctx)
 static bool
-cmd_buffer_prev(CommandContext &ctx)
+cmd_buffer_prev(const CommandContext &ctx)
 {
 	const auto cnt = ctx.editor.BufferCount();
 	if (cnt <= 1) {
@@ -947,7 +1237,7 @@ cmd_buffer_prev(CommandContext &ctx)
 static bool
-cmd_buffer_close(CommandContext &ctx)
+cmd_buffer_close(const CommandContext &ctx)
 {
 	if (ctx.editor.BufferCount() == 0)
 		return true;
@@ -1116,6 +1406,85 @@ cmd_insert_text(CommandContext &ctx)
 				ctx.editor.SetStatus(ctx.editor.PromptLabel() + ": " + ctx.editor.PromptText());
 				return true;
 			}
 			// Generic command prompt completion
 			if (kind == Editor::PromptKind::Command) {
 				std::string text = ctx.editor.PromptText();
 				// Split into command and arg prefix
 				auto sp = text.find(' ');
 				if (sp == std::string::npos) {
 					// complete command name from public commands
 					std::string prefix = text;
 					std::vector<std::string> names;
 					for (const auto &c: CommandRegistry::All()) {
 						if (c.isPublic) {
 							if (prefix.empty() || c.name.rfind(prefix, 0) == 0)
 								names.push_back(c.name);
 						}
 					}
 					if (names.empty()) {
 						// no change
 					} else if (names.size() == 1) {
 						ctx.editor.SetPromptText(names[0]);
 					} else {
 						// compute LCP
 						std::string lcp = names[0];
 						for (size_t i = 1; i < names.size(); ++i) {
 							const std::string &s = names[i];
 							size_t j             = 0;
 							while (j < lcp.size() && j < s.size() && lcp[j] == s[j])
 								++j;
 							lcp.resize(j);
 							if (lcp.empty())
 								break;
 						}
 						if (!lcp.empty() && lcp != text)
 							ctx.editor.SetPromptText(lcp);
 					}
 					ctx.editor.SetStatus(std::string(": ") + ctx.editor.PromptText());
 					return true;
 				} else {
 					std::string cmd       = text.substr(0, sp);
 					std::string argprefix = text.substr(sp + 1);
 					// Only special-case argument completion for certain commands
 					if (cmd == "theme") {
 #ifdef KTE_BUILD_GUI
 						std::vector<std::string> cands;
 						const auto &reg = kte::ThemeRegistry();
 						for (const auto &t: reg) {
 							std::string n = t->Name();
 							if (argprefix.empty() || n.rfind(argprefix, 0) == 0)
 								cands.push_back(n);
 						}
 						if (cands.empty()) {
 							// no change
 						} else if (cands.size() == 1) {
 							ctx.editor.SetPromptText(cmd + std::string(" ") + cands[0]);
 						} else {
 							std::string lcp = cands[0];
 							for (size_t i = 1; i < cands.size(); ++i) {
 								const std::string &s = cands[i];
 								size_t j             = 0;
 								while (j < lcp.size() && j < s.size() && lcp[j] == s[j])
 									++j;
 								lcp.resize(j);
 								if (lcp.empty())
 									break;
 							}
 							if (!lcp.empty() && lcp != argprefix)
 								ctx.editor.SetPromptText(cmd + std::string(" ") + lcp);
 						}
 						ctx.editor.SetStatus(std::string(": ") + ctx.editor.PromptText());
 						return true;
 #else
 						(void) argprefix; // no completion in non-GUI build
 #endif
 					}
 					// default: no special arg completion
 					ctx.editor.SetStatus(std::string(": ") + ctx.editor.PromptText());
 					return true;
 				}
 			}
 		}
 		ctx.editor.AppendPromptText(ctx.arg);
@@ -1223,6 +1592,7 @@ cmd_insert_text(CommandContext &ctx)
 	return true;
 }
 // Toggle read-only state of the current buffer
 static bool
 cmd_toggle_read_only(CommandContext &ctx)
@@ -1258,8 +1628,10 @@ cmd_show_help(CommandContext &ctx)
 		std::ostringstream out;
 		std::string line;
 		auto unquote = [](std::string s) {
-            if (!s.empty() && (s.front() == '"' || s.front() == '\'')) s.erase(s.begin());
+			if (!s.empty() && (s.front() == '"' || s.front() == '\''))
-            if (!s.empty() && (s.back() == '"' || s.back() == '\'')) s.pop_back();
+				s.erase(s.begin());
 			if (!s.empty() && (s.back() == '"' || s.back() == '\''))
 				s.pop_back();
 			return s;
 		};
 		while (std::getline(iss, line)) {
@@ -1275,17 +1647,20 @@ cmd_show_help(CommandContext &ctx)
 					std::string title;
 					std::getline(ls, title);
 					// trim leading spaces
-                    while (!title.empty() && (title.front() == ' ' || title.front() == '\t')) title.erase(title.begin());
+					while (!title.empty() && (title.front() == ' ' || title.front() == '\t'))
 						title.erase(title.begin());
 					title = unquote(title);
 					out << "\n\n";
-                    for (auto &c : title) c = static_cast<char>(std::toupper(static_cast<unsigned char>(c)));
+					for (auto &c: title)
 						c = static_cast<char>(std::toupper(static_cast<unsigned char>(c)));
 					out << title << "\n";
 				} else if (macro == "PP" || macro == "P" || macro == "TP") {
 					out << "\n";
 				} else if (macro == "B" || macro == "I" || macro == "BR" || macro == "IR") {
 					std::string rest;
 					std::getline(ls, rest);
-                    while (!rest.empty() && (rest.front() == ' ' || rest.front() == '\t')) rest.erase(rest.begin());
+					while (!rest.empty() && (rest.front() == ' ' || rest.front() == '\t'))
 						rest.erase(rest.begin());
 					out << unquote(rest) << "\n";
 				} else if (macro == "nf" || macro == "fi") {
 					// ignore fill mode toggles for now
@@ -1297,11 +1672,23 @@ cmd_show_help(CommandContext &ctx)
 			// Regular text; apply minimal escape replacements
 			for (std::size_t i = 0; i < line.size(); ++i) {
 				if (line[i] == '\\') {
-                    if (i + 1 < line.size() && line[i + 1] == '-') { out << '-'; ++i; continue; }
+					if (i + 1 < line.size() && line[i + 1] == '-') {
 						out << '-';
 						++i;
 						continue;
 					}
 					if (i + 3 < line.size() && line[i + 1] == '(') {
 						std::string esc = line.substr(i + 2, 2);
-                        if (esc == "em") { out << "—"; i += 3; continue; }
+						if (esc == "em") {
-                        if (esc == "en") { out << "-"; i += 3; continue; }
+							out << "—";
 							i += 3;
 							continue;
 						}
 						if (esc == "en") {
 							out << "-";
 							i += 3;
 							continue;
 						}
 					}
 				}
 				out << line[i];
@@ -1315,7 +1702,10 @@ cmd_show_help(CommandContext &ctx)
 		// 1) Prefer embedded/customizable help content
 		{
 			std::string embedded = HelpText::Text();
-            if (!embedded.empty()) { used_man = false; return embedded; }
+			if (!embedded.empty()) {
 				used_man = false;
 				return embedded;
 			}
 		}
 		// 2) Fall back to the manpage and convert roff to plain text
@@ -1329,7 +1719,10 @@ cmd_show_help(CommandContext &ctx)
 			std::ifstream in(p);
 			if (in.good()) {
 				std::string s((std::istreambuf_iterator<char>(in)), std::istreambuf_iterator<char>());
-                if (!s.empty()) { used_man = true; return roff_to_text(s); }
+				if (!s.empty()) {
 					used_man = true;
 					return roff_to_text(s);
 				}
 			}
 		}
 		// Fallback minimal help text
@@ -1430,6 +1823,46 @@ cmd_newline(CommandContext &ctx)
 		Editor::PromptKind kind = ctx.editor.CurrentPromptKind();
 		std::string value       = ctx.editor.PromptText();
 		ctx.editor.AcceptPrompt();
 		if (kind == Editor::PromptKind::Command) {
 			// Parse COMMAND ARG and dispatch only public commands
 			// Trim leading/trailing spaces
 			auto ltrim = [](std::string &s) {
 				s.erase(s.begin(), std::find_if(s.begin(), s.end(), [](unsigned char ch) {
 					return !std::isspace(ch);
 				}));
 			};
 			auto rtrim = [](std::string &s) {
 				s.erase(std::find_if(s.rbegin(), s.rend(), [](unsigned char ch) {
 					return !std::isspace(ch);
 				}).base(), s.end());
 			};
 			ltrim(value);
 			rtrim(value);
 			if (value.empty()) {
 				ctx.editor.SetStatus("Canceled");
 				return true;
 			}
 			// Split first token
 			std::string cmdname;
 			std::string arg;
 			auto sp = value.find(' ');
 			if (sp == std::string::npos) {
 				cmdname = value;
 			} else {
 				cmdname = value.substr(0, sp);
 				arg     = value.substr(sp + 1);
 			}
 			const Command *cmd = CommandRegistry::FindByName(cmdname);
 			if (!cmd || !cmd->isPublic) {
 				ctx.editor.SetStatus(std::string("Unknown command: ") + cmdname);
 				return true;
 			}
 			bool ok = Execute(ctx.editor, cmdname, arg);
 			if (!ok) {
 				ctx.editor.SetStatus(std::string("Command failed: ") + cmdname);
 			}
 			return true;
 		}
 		if (kind == Editor::PromptKind::Search || kind == Editor::PromptKind::RegexSearch) {
 			// Finish search: keep cursor where it is, clear search UI prompt
 			ctx.editor.SetSearchActive(false);
@@ -3275,7 +3708,25 @@ InstallDefaultCommands()
 		CommandId::ReflowParagraph, "reflow-paragraph", "Reflow paragraph to column width", cmd_reflow_paragraph
 	});
 	// Read-only
- CommandRegistry::Register({CommandId::ToggleReadOnly, "toggle-read-only", "Toggle buffer read-only", cmd_toggle_read_only});
+	CommandRegistry::Register({
 		CommandId::ToggleReadOnly, "toggle-read-only", "Toggle buffer read-only", cmd_toggle_read_only
 	});
 	// GUI Themes
 	CommandRegistry::Register({CommandId::ThemeNext, "theme-next", "Cycle to next GUI theme", cmd_theme_next});
 	CommandRegistry::Register({CommandId::ThemePrev, "theme-prev", "Cycle to previous GUI theme", cmd_theme_prev});
 	// Theme by name (public in command prompt)
 	CommandRegistry::Register({
 		CommandId::ThemeSetByName, "theme", "Set GUI theme by name", cmd_theme_set_by_name, true
 	});
 	// Background light/dark (public)
 	CommandRegistry::Register({
 		CommandId::BackgroundSet, "background", "Set GUI background light|dark", cmd_background_set, true
 	});
 	// Generic command prompt (C-k ;)
 	CommandRegistry::Register({
 		CommandId::CommandPromptStart, "command-prompt-start", "Start generic command prompt",
 		cmd_command_prompt_start
 	});
 	// Buffer operations
 	CommandRegistry::Register({
 		CommandId::ReloadBuffer, "reload-buffer", "Reload buffer from disk", cmd_reload_buffer
@@ -3305,6 +3756,9 @@ InstallDefaultCommands()
 	// UI helpers
 	CommandRegistry::Register(
 		{CommandId::UArgStatus, "uarg-status", "Update universal-arg status", cmd_uarg_status});
 	// Syntax highlighting (public commands)
 	CommandRegistry::Register({CommandId::Syntax, "syntax", "Syntax: on|off|reload", cmd_syntax, true});
 	CommandRegistry::Register({CommandId::SetOption, "set", "Set option: key=value", cmd_set_option, true});
 }
--- a/Command.h
+++ b/Command.h
@@ -69,6 +69,9 @@ enum class CommandId {
 	Redo,
 	// UI/status helpers
 	UArgStatus, // update status line during universal-argument collection
 	// Themes (GUI)
 	ThemeNext,
 	ThemePrev,
 	// Region formatting
 	IndentRegion, // indent region (C-k =)
 	UnindentRegion, // unindent region (C-k -)
@@ -86,6 +89,15 @@ enum class CommandId {
 	ShowHelp, // open +HELP+ buffer with manual text (C-k h)
 	// Meta
 	UnknownKCommand, // arg: single character that was not recognized after C-k
 	// Generic command prompt
 	CommandPromptStart, // begin generic command prompt (C-k ;)
 	// Theme by name
 	ThemeSetByName,
 	// Background mode (GUI)
 	BackgroundSet,
 	// Syntax highlighting
 	Syntax, // ":syntax on|off|reload"
 	SetOption, // generic ":set key=value" (v1: filetype=<lang>)
 };
@@ -109,6 +121,8 @@ struct Command {
 	std::string name; // stable, unique name (e.g., "save", "save-as")
 	std::string help; // short help/description
 	CommandHandler handler;
 	// Public commands are exposed in the ": " prompt (C-k ;)
 	bool isPublic = false;
 };
--- a/Editor.cc
+++ b/Editor.cc
@@ -3,6 +3,9 @@
 #include <filesystem>
 #include "Editor.h"
 #include "syntax/HighlighterRegistry.h"
 #include "syntax/CppHighlighter.h"
 #include "syntax/NullHighlighter.h"
 Editor::Editor() = default;
@@ -151,7 +154,32 @@ Editor::OpenFile(const std::string &path, std::string &err)
 		const bool rows_empty        = rows.empty();
 		const bool single_empty_line = (!rows.empty() && rows.size() == 1 && rows[0].size() == 0);
 		if (unnamed && clean && (rows_empty || single_empty_line)) {
-			return cur.OpenFromFile(path, err);
+			bool ok = cur.OpenFromFile(path, err);
 			if (!ok)
 				return false;
 			// Setup highlighting using registry (extension + shebang)
 			cur.EnsureHighlighter();
 			std::string first = "";
 			const auto &rows  = cur.Rows();
 			if (!rows.empty())
 				first = static_cast<std::string>(rows[0]);
 			std::string ft = kte::HighlighterRegistry::DetectForPath(path, first);
 			if (!ft.empty()) {
 				cur.SetFiletype(ft);
 				cur.SetSyntaxEnabled(true);
 				if (auto *eng = cur.Highlighter()) {
 					eng->SetHighlighter(kte::HighlighterRegistry::CreateFor(ft));
 					eng->InvalidateFrom(0);
 				}
 			} else {
 				cur.SetFiletype("");
 				cur.SetSyntaxEnabled(true);
 				if (auto *eng = cur.Highlighter()) {
 					eng->SetHighlighter(std::make_unique<kte::NullHighlighter>());
 					eng->InvalidateFrom(0);
 				}
 			}
 			return true;
 		}
 	}
@@ -159,6 +187,30 @@ Editor::OpenFile(const std::string &path, std::string &err)
 	if (!b.OpenFromFile(path, err)) {
 		return false;
 	}
 	// Initialize syntax highlighting by extension + shebang via registry (v2)
 	b.EnsureHighlighter();
 	std::string first = "";
 	{
 		const auto &rows = b.Rows();
 		if (!rows.empty())
 			first = static_cast<std::string>(rows[0]);
 	}
 	std::string ft = kte::HighlighterRegistry::DetectForPath(path, first);
 	if (!ft.empty()) {
 		b.SetFiletype(ft);
 		b.SetSyntaxEnabled(true);
 		if (auto *eng = b.Highlighter()) {
 			eng->SetHighlighter(kte::HighlighterRegistry::CreateFor(ft));
 			eng->InvalidateFrom(0);
 		}
 	} else {
 		b.SetFiletype("");
 		b.SetSyntaxEnabled(true);
 		if (auto *eng = b.Highlighter()) {
 			eng->SetHighlighter(std::make_unique<kte::NullHighlighter>());
 			eng->InvalidateFrom(0);
 		}
 	}
 	// Add as a new buffer and switch to it
 	std::size_t idx = AddBuffer(std::move(b));
 	SwitchTo(idx);
@@ -173,6 +225,27 @@ Editor::SwitchTo(std::size_t index)
 		return false;
 	}
 	curbuf_ = index;
 	// Robustness: ensure a valid highlighter is installed when switching buffers
 	Buffer &b = buffers_[curbuf_];
 	if (b.SyntaxEnabled()) {
 		b.EnsureHighlighter();
 		if (auto *eng = b.Highlighter()) {
 			if (!eng->HasHighlighter()) {
 				// Try to set based on existing filetype; fall back to NullHighlighter
 				if (!b.Filetype().empty()) {
 					auto hl = kte::HighlighterRegistry::CreateFor(b.Filetype());
 					if (hl) {
 						eng->SetHighlighter(std::move(hl));
 					} else {
 						eng->SetHighlighter(std::make_unique<kte::NullHighlighter>());
 					}
 				} else {
 					eng->SetHighlighter(std::make_unique<kte::NullHighlighter>());
 				}
 				eng->InvalidateFrom(0);
 			}
 		}
 	}
 	return true;
 }
--- a/Editor.h
+++ b/Editor.h
@@ -315,7 +315,8 @@ public:
 		GotoLine,
 		Chdir,
 		ReplaceFind, // step 1 of Search & Replace: find what
-     ReplaceWith   // step 2 of Search & Replace: replace with
+		ReplaceWith, // step 2 of Search & Replace: replace with
 		Command // generic command prompt (": ")
 	};
@@ -524,10 +525,28 @@ private:
 	// Temporary state for Search & Replace flow
 public:
-    void SetReplaceFindTmp(const std::string &s) { replace_find_tmp_ = s; }
+	void SetReplaceFindTmp(const std::string &s)
-    void SetReplaceWithTmp(const std::string &s) { replace_with_tmp_ = s; }
+	{
-    [[nodiscard]] const std::string &ReplaceFindTmp() const { return replace_find_tmp_; }
+		replace_find_tmp_ = s;
-    [[nodiscard]] const std::string &ReplaceWithTmp() const { return replace_with_tmp_; }
+	}
 	void SetReplaceWithTmp(const std::string &s)
 	{
 		replace_with_tmp_ = s;
 	}
 	[[nodiscard]] const std::string &ReplaceFindTmp() const
 	{
 		return replace_find_tmp_;
 	}
 	[[nodiscard]] const std::string &ReplaceWithTmp() const
 	{
 		return replace_with_tmp_;
 	}
 private:
 	std::string replace_find_tmp_;
--- a/GUIConfig.cc
+++ b/GUIConfig.cc
@@ -102,6 +102,25 @@ GUIConfig::LoadFromFile(const std::string &path)
 			if (v > 0.0f) {
 				font_size = v;
 			}
 		} else if (key == "theme") {
 			theme = val;
 		} else if (key == "background" || key == "bg") {
 			std::string v = val;
 			std::transform(v.begin(), v.end(), v.begin(), [](unsigned char c) {
 				return (char) std::tolower(c);
 			});
 			if (v == "light" || v == "dark")
 				background = v;
 		} else if (key == "syntax") {
 			std::string v = val;
 			std::transform(v.begin(), v.end(), v.begin(), [](unsigned char c) {
 				return (char) std::tolower(c);
 			});
 			if (v == "1" || v == "on" || v == "true" || v == "yes") {
 				syntax = true;
 			} else if (v == "0" || v == "off" || v == "false" || v == "no") {
 				syntax = false;
 			}
 		}
 	}
--- a/GUIConfig.h
+++ b/GUIConfig.h
@@ -16,6 +16,14 @@ public:
 	int columns       = 80;
 	int rows          = 42;
 	float font_size   = (float) KTE_FONT_SIZE;
 	std::string theme = "nord";
 	// Background mode for themes that support light/dark variants
 	// Values: "dark" (default), "light"
 	std::string background = "dark";
 	// Default syntax highlighting state for GUI (kge): on/off
 	// Accepts: on/off/true/false/yes/no/1/0 in the ini file.
 	bool syntax = true; // default: enabled
 	// Load from default path: $HOME/.config/kte/kge.ini
 	static GUIConfig Load();
--- a/GUIFrontend.cc
+++ b/GUIFrontend.cc
@@ -16,6 +16,8 @@
 #include "Font.h" // embedded default font (DefaultFontRegular)
 #include "GUIConfig.h"
 #include "GUITheme.h"
 #include "syntax/HighlighterRegistry.h"
 #include "syntax/NullHighlighter.h"
 #ifndef KTE_FONT_SIZE
@@ -32,8 +34,8 @@ GUIFrontend::Init(Editor &ed)
 		return false;
 	}
-	// Load GUI configuration (fullscreen, columns/rows, font size)
+	// Load GUI configuration (fullscreen, columns/rows, font size, theme, background)
-	const auto [fullscreen, columns, rows, font_size] = GUIConfig::Load();
+	GUIConfig cfg = GUIConfig::Load();
 	// GL attributes for core profile
 	SDL_GL_SetAttribute(SDL_GL_CONTEXT_FLAGS, 0);
@@ -47,7 +49,7 @@ GUIFrontend::Init(Editor &ed)
 	// Compute desired window size from config
 	Uint32 win_flags = SDL_WINDOW_OPENGL | SDL_WINDOW_RESIZABLE | SDL_WINDOW_ALLOW_HIGHDPI;
-	if (fullscreen) {
+	if (cfg.fullscreen) {
 		// "Fullscreen": fill the usable bounds of the primary display.
 		// On macOS, do NOT use true fullscreen so the menu/status bar remains visible.
 		SDL_Rect usable{};
@@ -61,8 +63,8 @@ GUIFrontend::Init(Editor &ed)
 #endif
 	} else {
 		// Windowed: width = columns * font_size, height = (rows * 2) * font_size
-		int w = static_cast<int>(columns * font_size);
+		int w = cfg.columns * static_cast<int>(cfg.font_size);
-		int h = static_cast<int>((rows * 2) * font_size);
+		int h = cfg.rows * static_cast<int>(cfg.font_size * 1.2);
 		// As a safety, clamp to display usable bounds if retrievable
 		SDL_Rect usable{};
@@ -86,7 +88,7 @@ GUIFrontend::Init(Editor &ed)
 	// macOS: when "fullscreen" is requested, position the window at the
 	// top-left of the usable display area to mimic fullscreen while keeping
 	// the system menu bar visible.
-	if (fullscreen) {
+	if (cfg.fullscreen) {
 		SDL_Rect usable{};
 		if (SDL_GetDisplayUsableBounds(0, &usable) == 0) {
 			SDL_SetWindowPosition(window_, usable.x, usable.y);
@@ -105,8 +107,45 @@ GUIFrontend::Init(Editor &ed)
 	ImGuiIO &io = ImGui::GetIO();
 	(void) io;
 	ImGui::StyleColorsDark();
-	// Apply a Nord-inspired theme
+
-	kte::ApplyNordImGuiTheme();
+	// Apply background mode and selected theme (default: Nord). Can be changed at runtime via commands.
 	if (cfg.background == "light")
 		kte::SetBackgroundMode(kte::BackgroundMode::Light);
 	else
 		kte::SetBackgroundMode(kte::BackgroundMode::Dark);
 	kte::ApplyThemeByName(cfg.theme);
 	// Apply default syntax highlighting preference from GUI config to the current buffer
 	if (Buffer *b = ed.CurrentBuffer()) {
 		if (cfg.syntax) {
 			b->SetSyntaxEnabled(true);
 			// Ensure a highlighter is available if possible
 			b->EnsureHighlighter();
 			if (auto *eng = b->Highlighter()) {
 				if (!eng->HasHighlighter()) {
 					// Try detect from filename and first line; fall back to cpp or existing filetype
 					std::string first_line;
 					const auto &rows = b->Rows();
 					if (!rows.empty())
 						first_line = static_cast<std::string>(rows[0]);
 					std::string ft = kte::HighlighterRegistry::DetectForPath(
 						b->Filename(), first_line);
 					if (!ft.empty()) {
 						eng->SetHighlighter(kte::HighlighterRegistry::CreateFor(ft));
 						b->SetFiletype(ft);
 						eng->InvalidateFrom(0);
 					} else {
 						// Unknown/unsupported -> install a null highlighter to keep syntax enabled
 						eng->SetHighlighter(std::make_unique<kte::NullHighlighter>());
 						b->SetFiletype("");
 						eng->InvalidateFrom(0);
 					}
 				}
 			}
 		} else {
 			b->SetSyntaxEnabled(false);
 		}
 	}
 	if (!ImGui_ImplSDL2_InitForOpenGL(window_, gl_ctx_))
 		return false;
@@ -135,7 +174,7 @@ GUIFrontend::Init(Editor &ed)
 #endif
 	// Initialize GUI font from embedded default (use configured size or compiled default)
-	LoadGuiFont_(nullptr, (float) font_size);
+	LoadGuiFont_(nullptr, (float) cfg.font_size);
 	return true;
 }
@@ -214,7 +253,7 @@ GUIFrontend::Step(Editor &ed, bool &running)
 		float avail_h = std::max(0.0f, disp_h - 2.0f * pad_y - status_h);
 		// Visible content rows inside the scroll child
-		std::size_t content_rows = static_cast<std::size_t>(std::floor(avail_h / line_h));
+		auto content_rows = static_cast<std::size_t>(std::floor(avail_h / line_h));
 		// Editor::Rows includes the status line; add 1 back for it.
 		std::size_t rows = std::max<std::size_t>(1, content_rows + 1);
 		std::size_t cols = static_cast<std::size_t>(std::max(1.0f, std::floor(avail_w / ch_w)));
@@ -264,11 +303,11 @@ GUIFrontend::Shutdown()
 bool
 GUIFrontend::LoadGuiFont_(const char * /*path*/, float size_px)
 {
-	ImGuiIO &io = ImGui::GetIO();
+	const ImGuiIO &io = ImGui::GetIO();
 	io.Fonts->Clear();
-	ImFont *font = io.Fonts->AddFontFromMemoryCompressedTTF(
+	const ImFont *font = io.Fonts->AddFontFromMemoryCompressedTTF(
-		(void *) DefaultFontBoldCompressedData,
+		DefaultFontBoldCompressedData,
-		(int) DefaultFontBoldCompressedSize,
+		DefaultFontBoldCompressedSize,
 		size_px);
 	if (!font) {
 		font = io.Fonts->AddFontDefault();
--- a/GUIFrontend.h
+++ b/GUIFrontend.h
@@ -25,7 +25,7 @@ public:
 	void Shutdown() override;
 private:
-	bool LoadGuiFont_(const char *path, float size_px);
+	static bool LoadGuiFont_(const char *path, float size_px);
 	GUIInputHandler input_{};
 	GUIRenderer renderer_{};
--- a/GUIInputHandler.cc
+++ b/GUIInputHandler.cc
@@ -3,6 +3,7 @@
 #include <ncurses.h>
 #include <SDL.h>
 #include <imgui.h>
 #include "GUIInputHandler.h"
 #include "KKeymap.h"
@@ -92,10 +93,14 @@ map_key(const SDL_Keycode key,
 		out = {true, CommandId::Backspace, "", 0};
 		return true;
 	case SDLK_TAB:
-		// Do not insert text on KEYDOWN; allow SDL_TEXTINPUT to deliver '\t'
+		// Insert a literal tab character when not interpreting a k-prefix suffix.
-		// as printable input so that all printable characters flow via TEXTINPUT.
+		// If k-prefix is active, let the k-prefix handler below consume the key
-		out.hasCommand = false;
+		// (so Tab doesn't leave k-prefix stuck).
 		if (!k_prefix) {
 			out = {true, CommandId::InsertText, std::string("\t"), 0};
 			return true;
 		}
 		break; // fall through so k-prefix handler can process
 	case SDLK_RETURN:
 	case SDLK_KP_ENTER:
 		out = {true, CommandId::Newline, "", 0};
@@ -280,6 +285,14 @@ GUIInputHandler::ProcessSDLEvent(const SDL_Event &e)
 	bool produced = false;
 	switch (e.type) {
 	case SDL_MOUSEWHEEL: {
 		// If ImGui wants to capture the mouse (e.g., hovering the File Picker list),
 		// don't translate wheel events into editor scrolling.
 		// This prevents background buffer scroll while using GUI widgets.
 		ImGuiIO &io = ImGui::GetIO();
 		if (io.WantCaptureMouse) {
 			return true; // consumed by GUI
 		}
 		// Map vertical wheel to line-wise cursor movement (MoveUp/MoveDown)
 		int dy = e.wheel.y;
 #ifdef SDL_MOUSEWHEEL_FLIPPED
@@ -347,6 +360,12 @@ GUIInputHandler::ProcessSDLEvent(const SDL_Event &e)
 		                   uarg_text_,
 		                   mi);
 		// If we inserted a TAB on KEYDOWN, suppress any subsequent SDL_TEXTINPUT
 		// for this keystroke to avoid double insertion on platforms that emit it.
 		if (produced && mi.hasCommand && mi.id == CommandId::InsertText && mi.arg == "\t") {
 			suppress_text_input_once_ = true;
 		}
 		// If we just consumed a universal-argument digit or '-' on KEYDOWN and emitted UArgStatus,
 		// suppress the subsequent SDL_TEXTINPUT for this keystroke to avoid duplicating the digit in status.
 		if (produced && mi.hasCommand && mi.id == CommandId::UArgStatus) {
--- a/GUIRenderer.cc
+++ b/GUIRenderer.cc
@@ -10,6 +10,8 @@
 #include <regex>
 #include "GUIRenderer.h"
 #include "Highlight.h"
 #include "GUITheme.h"
 #include "Buffer.h"
 #include "Command.h"
 #include "Editor.h"
@@ -44,6 +46,8 @@ GUIRenderer::Draw(Editor &ed)
 	ImGui::SetNextWindowSize(main_sz);
 	ImGuiWindowFlags flags = ImGuiWindowFlags_NoTitleBar
 	                         | ImGuiWindowFlags_NoScrollbar
 	                         | ImGuiWindowFlags_NoScrollWithMouse
 	                         | ImGuiWindowFlags_NoResize
 	                         | ImGuiWindowFlags_NoMove
 	                         | ImGuiWindowFlags_NoCollapse
@@ -151,6 +155,12 @@ GUIRenderer::Draw(Editor &ed)
 					last_row  = first_row + vis_rows - 1;
 				}
 			}
 			// Phase 3: prefetch visible viewport highlights and warm around in background
 			if (buf->SyntaxEnabled() && buf->Highlighter() && buf->Highlighter()->HasHighlighter()) {
 				int fr = static_cast<int>(std::max(0L, first_row));
 				int rc = static_cast<int>(std::max(1L, vis_rows));
 				buf->Highlighter()->PrefetchViewport(*buf, fr, rc, buf->Version());
 			}
 		}
 		// Handle mouse click before rendering to avoid dependent on drawn items
 		if (ImGui::IsWindowHovered() && ImGui::IsMouseClicked(ImGuiMouseButton_Left)) {
@@ -257,7 +267,9 @@ GUIRenderer::Draw(Editor &ed)
 			std::vector<std::pair<std::size_t, std::size_t> > hl_src_ranges;
 			if (search_mode) {
 				// If we're in RegexSearch or RegexReplaceFind mode, compute ranges using regex; otherwise plain substring
-                if (ed.PromptActive() && (ed.CurrentPromptKind() == Editor::PromptKind::RegexSearch || ed.CurrentPromptKind() == Editor::PromptKind::RegexReplaceFind)) {
+				if (ed.PromptActive() && (
 					    ed.CurrentPromptKind() == Editor::PromptKind::RegexSearch || ed.
 					    CurrentPromptKind() == Editor::PromptKind::RegexReplaceFind)) {
 					try {
 						std::regex rx(ed.SearchQuery());
 						for (auto it = std::sregex_iterator(line.begin(), line.end(), rx);
@@ -302,23 +314,26 @@ GUIRenderer::Draw(Editor &ed)
 					std::size_t rx_start = src_to_rx(sx);
 					std::size_t rx_end   = src_to_rx(ex);
 					// Apply horizontal scroll offset
-                    if (rx_end <= coloffs_now) continue; // fully left of view
+					if (rx_end <= coloffs_now)
 						continue; // fully left of view
 					std::size_t vx0 = (rx_start > coloffs_now) ? (rx_start - coloffs_now) : 0;
 					std::size_t vx1 = rx_end - coloffs_now;
 					ImVec2 p0 = ImVec2(line_pos.x + static_cast<float>(vx0) * space_w, line_pos.y);
-                    ImVec2 p1 = ImVec2(line_pos.x + static_cast<float>(vx1) * space_w, line_pos.y + line_h);
+					ImVec2 p1 = ImVec2(line_pos.x + static_cast<float>(vx1) * space_w,
 					                   line_pos.y + line_h);
 					// Choose color: current match stronger
 					bool is_current = has_current && sx == cur_x && ex == cur_end;
-                    ImU32 col = is_current ? IM_COL32(255, 220, 120, 140) : IM_COL32(200, 200, 0, 90);
+					ImU32 col       = is_current
 						                  ? IM_COL32(255, 220, 120, 140)
 						                  : IM_COL32(200, 200, 0, 90);
 					ImGui::GetWindowDrawList()->AddRectFilled(p0, p1, col);
 				}
 			}
-            // Emit entire line (ImGui child scrolling will handle clipping)
+			// Emit entire line to an expanded buffer (tabs -> spaces)
 			for (std::size_t src = 0; src < line.size(); ++src) {
 				char c = line[src];
 				if (c == '\t') {
 					std::size_t adv = (tabw - (rx_abs_draw % tabw));
                    // Emit spaces for the tab
 					expanded.append(adv, ' ');
 					rx_abs_draw += adv;
 				} else {
@@ -327,7 +342,43 @@ GUIRenderer::Draw(Editor &ed)
 				}
 			}
 			// Draw syntax-colored runs (text above background highlights)
 			if (buf->SyntaxEnabled() && buf->Highlighter() && buf->Highlighter()->HasHighlighter()) {
 				const kte::LineHighlight &lh = buf->Highlighter()->GetLine(
 					*buf, static_cast<int>(i), buf->Version());
 				// Helper to convert a src column to expanded rx position
 				auto src_to_rx_full = [&](std::size_t sidx) -> std::size_t {
 					std::size_t rx = 0;
 					for (std::size_t k = 0; k < sidx && k < line.size(); ++k) {
 						rx += (line[k] == '\t') ? (tabw - (rx % tabw)) : 1;
 					}
 					return rx;
 				};
 				for (const auto &sp: lh.spans) {
 					std::size_t rx_s = src_to_rx_full(
 						static_cast<std::size_t>(std::max(0, sp.col_start)));
 					std::size_t rx_e = src_to_rx_full(
 						static_cast<std::size_t>(std::max(sp.col_start, sp.col_end)));
 					if (rx_e <= coloffs_now)
 						continue;
 					std::size_t vx0 = (rx_s > coloffs_now) ? (rx_s - coloffs_now) : 0;
 					std::size_t vx1 = (rx_e > coloffs_now) ? (rx_e - coloffs_now) : 0;
 					if (vx0 >= expanded.size())
 						continue;
 					vx1 = std::min<std::size_t>(vx1, expanded.size());
 					if (vx1 <= vx0)
 						continue;
 					ImU32 col = ImGui::GetColorU32(kte::SyntaxInk(sp.kind));
 					ImVec2 p  = ImVec2(line_pos.x + static_cast<float>(vx0) * space_w, line_pos.y);
 					ImGui::GetWindowDrawList()->AddText(
 						p, col, expanded.c_str() + vx0, expanded.c_str() + vx1);
 				}
 				// We drew text via draw list (no layout advance). Manually advance the cursor to the next line.
 				ImGui::SetCursorScreenPos(ImVec2(line_pos.x, line_pos.y + line_h));
 			} else {
 				// No syntax: draw as one run
 				ImGui::TextUnformatted(expanded.c_str());
 			}
 			// Draw a visible cursor indicator on the current line
 			if (i == cy) {
@@ -390,13 +441,18 @@ GUIRenderer::Draw(Editor &ed)
 			float max_px  = std::max(0.0f, right_x - left_x);
 			std::string prefix;
-      if (!label.empty()) prefix = label + ": ";
+			if (kind == Editor::PromptKind::Command) {
 				prefix = ": ";
 			} else if (!label.empty()) {
 				prefix = label + ": ";
 			}
 			// Compose showing right-end of filename portion when too long for space
 			std::string final_msg;
 			ImVec2 prefix_sz = ImGui::CalcTextSize(prefix.c_str());
 			float avail_px   = std::max(0.0f, max_px - prefix_sz.x);
-      if ((kind == Editor::PromptKind::OpenFile || kind == Editor::PromptKind::SaveAs || kind == Editor::PromptKind::Chdir) && avail_px > 0.0f) {
+			if ((kind == Editor::PromptKind::OpenFile || kind == Editor::PromptKind::SaveAs || kind ==
 			     Editor::PromptKind::Chdir) && avail_px > 0.0f) {
 				// Trim from left until it fits by pixel width
 				std::string tail = ptext;
 				ImVec2 tail_sz   = ImGui::CalcTextSize(tail.c_str());
@@ -408,7 +464,11 @@ GUIRenderer::Draw(Editor &ed)
 					while (start < tail.size()) {
 						// Estimate how many chars to skip based on ratio
 						float ratio = tail_sz.x / avail_px;
-                  size_t skip = ratio > 1.5f ? std::min(tail.size() - start, (size_t)std::max<size_t>(1, (size_t)(tail.size() / 4))) : 1;
+						size_t skip = ratio > 1.5f
 							              ? std::min(tail.size() - start,
 								              (size_t) std::max<size_t>(
 									              1, (size_t) (tail.size() / 4)))
 							              : 1;
 						start += skip;
 						std::string candidate = tail.substr(start);
 						ImVec2 cand_sz        = ImGui::CalcTextSize(candidate.c_str());
@@ -425,7 +485,10 @@ GUIRenderer::Draw(Editor &ed)
 						while (lo < hi) {
 							size_t mid       = (lo + hi) / 2;
 							std::string cand = tail.substr(mid);
-                      if (ImGui::CalcTextSize(cand.c_str()).x <= avail_px) hi = mid; else lo = mid + 1;
+							if (ImGui::CalcTextSize(cand.c_str()).x <= avail_px)
 								hi = mid;
 							else
 								lo = mid + 1;
 						}
 						tail = tail.substr(lo);
 					}
@@ -529,7 +592,8 @@ GUIRenderer::Draw(Editor &ed)
 			}
 			// Draw right
-		ImGui::SetCursorScreenPos(ImVec2(std::max(right_x, left_x), p0.y + (bar_h - right_sz.y) * 0.5f));
+			ImGui::SetCursorScreenPos(ImVec2(std::max(right_x, left_x),
 			                                 p0.y + (bar_h - right_sz.y) * 0.5f));
 			ImGui::TextUnformatted(right.c_str());
 			// Draw middle message centered in remaining space
--- a/GUITheme.h
+++ b/GUITheme.h
@@ -1,127 +1,415 @@
-// GUITheme.h - ImGui theme configuration for kte GUI
+// GUITheme.h — ImGui theming helpers and background mode
 // Provides a Nord-inspired color palette and style settings.
 #pragma once
 #include <imgui.h>
 #include <vector>
 #include <memory>
 #include <string>
 #include <cstddef>
 #include <algorithm>
 #include <cctype>
 #include "themes/ThemeHelpers.h"
 namespace kte {
-// Convert RGB hex (0xRRGGBB) to ImVec4 with optional alpha
+// Background mode selection for light/dark palettes
-static inline ImVec4
+enum class BackgroundMode { Light, Dark };
-RGBA(unsigned int rgb, float a = 1.0f)
+
 // Global background mode; default to Dark to match prior defaults
 static inline auto gBackgroundMode = BackgroundMode::Dark;
 // Basic theme identifier (kept minimal; some ids are aliases)
 enum class ThemeId {
 	EInk = 0,
 	GruvboxDarkMedium = 1,
 	GruvboxLightMedium = 1, // alias to unified gruvbox index
 	Nord = 2,
 	Plan9 = 3,
 	Solarized = 4,
 };
 // Current theme tracking
 static inline auto gCurrentTheme             = ThemeId::Nord;
 static inline std::size_t gCurrentThemeIndex = 0;
 // Forward declarations for helpers used below
 static size_t ThemeIndexFromId(ThemeId id);
 static ThemeId ThemeIdFromIndex(size_t idx);
 // Helpers to set/query background mode
 static void
 SetBackgroundMode(const BackgroundMode m)
 {
-	float r = ((rgb >> 16) & 0xFF) / 255.0f;
+	gBackgroundMode = m;
 	float g = ((rgb >> 8) & 0xFF) / 255.0f;
 	float b = ((rgb) & 0xFF) / 255.0f;
 	return ImVec4(r, g, b, a);
 }
-// Apply a Nord-inspired theme to the current ImGui style.
+static BackgroundMode
-// Safe to call after ImGui::CreateContext().
+GetBackgroundMode()
 static inline void
 ApplyNordImGuiTheme()
 {
-	// Nord palette
+	return gBackgroundMode;
-	const ImVec4 nord0  = RGBA(0x2E3440); // darkest bg
+}
 	const ImVec4 nord1  = RGBA(0x3B4252);
 	const ImVec4 nord2  = RGBA(0x434C5E);
 	const ImVec4 nord3  = RGBA(0x4C566A);
 	const ImVec4 nord4  = RGBA(0xD8DEE9);
 	const ImVec4 nord6  = RGBA(0xECEFF4); // lightest
 	const ImVec4 nord8  = RGBA(0x88C0D0); // cyan
 	const ImVec4 nord9  = RGBA(0x81A1C1); // blue
 	const ImVec4 nord10 = RGBA(0x5E81AC); // blue dark
 	const ImVec4 nord12 = RGBA(0xD08770); // orange
 	const ImVec4 nord13 = RGBA(0xEBCB8B); // yellow
 	ImGuiStyle &style = ImGui::GetStyle();
-	// Base style tweaks to suit Nord aesthetics
+static inline const char *
-	style.WindowPadding    = ImVec2(8.0f, 8.0f);
+BackgroundModeName()
-	style.FramePadding     = ImVec2(6.0f, 4.0f);
+{
-	style.CellPadding      = ImVec2(6.0f, 4.0f);
+	return gBackgroundMode == BackgroundMode::Light ? "light" : "dark";
-	style.ItemSpacing      = ImVec2(6.0f, 6.0f);
+}
 	style.ItemInnerSpacing = ImVec2(6.0f, 4.0f);
 	style.ScrollbarSize    = 14.0f;
 	style.GrabMinSize      = 10.0f;
 	style.WindowRounding   = 4.0f;
 	style.FrameRounding    = 3.0f;
 	style.PopupRounding    = 4.0f;
 	style.GrabRounding     = 3.0f;
 	style.TabRounding      = 4.0f;
 	style.WindowBorderSize = 1.0f;
 	style.FrameBorderSize  = 1.0f;
 	ImVec4 *colors = style.Colors;
-	colors[ImGuiCol_Text]         = nord4; // primary text
+// Include individual theme implementations split under ./themes
-	colors[ImGuiCol_TextDisabled] = ImVec4(nord4.x, nord4.y, nord4.z, 0.55f);
+#include "themes/Nord.h"
-	colors[ImGuiCol_WindowBg]     = nord10;
+#include "themes/Plan9.h"
-	colors[ImGuiCol_ChildBg]      = nord0;
+#include "themes/Solarized.h"
-	colors[ImGuiCol_PopupBg]      = RGBA(0x2E3440, 0.98f);
+#include "themes/Gruvbox.h"
-	colors[ImGuiCol_Border]       = nord1;
+#include "themes/EInk.h"
 	colors[ImGuiCol_BorderShadow] = RGBA(0x000000, 0.0f);
 	colors[ImGuiCol_FrameBg]        = nord2;
 	colors[ImGuiCol_FrameBgHovered] = nord3;
 	colors[ImGuiCol_FrameBgActive]  = nord10;
-	colors[ImGuiCol_TitleBg]          = nord1;
+// Theme abstraction and registry (generalized theme system)
-	colors[ImGuiCol_TitleBgActive]    = nord3;
+class Theme {
-	colors[ImGuiCol_TitleBgCollapsed] = nord1;
+public:
 	virtual ~Theme() = default;
-	colors[ImGuiCol_MenuBarBg]            = nord1;
+	[[nodiscard]] virtual const char *Name() const = 0; // canonical name (e.g., "nord", "gruvbox-dark")
-	colors[ImGuiCol_ScrollbarBg]          = nord0;
+	virtual void Apply() const = 0; // apply to current ImGui style
-	colors[ImGuiCol_ScrollbarGrab]        = nord3;
+	virtual ThemeId Id() = 0; // theme identifier
-	colors[ImGuiCol_ScrollbarGrabHovered] = nord10;
+};
 	colors[ImGuiCol_ScrollbarGrabActive]  = nord9;
-	colors[ImGuiCol_CheckMark]        = nord8;
+namespace detail {
-	colors[ImGuiCol_SliderGrab]       = nord8;
+struct NordTheme final : Theme {
-	colors[ImGuiCol_SliderGrabActive] = nord9;
+	[[nodiscard]] const char *Name() const override
 	{
 		return "nord";
 	}
 	colors[ImGuiCol_Button]        = nord3;
 	colors[ImGuiCol_ButtonHovered] = nord10;
 	colors[ImGuiCol_ButtonActive]  = nord9;
-	colors[ImGuiCol_Header]        = nord3;
+	void Apply() const override
-	colors[ImGuiCol_HeaderHovered] = nord10;
+	{
-	colors[ImGuiCol_HeaderActive]  = nord10;
+		ApplyNordImGuiTheme();
 	}
 	colors[ImGuiCol_Separator]        = nord2;
 	colors[ImGuiCol_SeparatorHovered] = nord10;
 	colors[ImGuiCol_SeparatorActive]  = nord9;
-	colors[ImGuiCol_ResizeGrip]        = ImVec4(nord6.x, nord6.y, nord6.z, 0.12f);
+	ThemeId Id() override
-	colors[ImGuiCol_ResizeGripHovered] = ImVec4(nord8.x, nord8.y, nord8.z, 0.67f);
+	{
-	colors[ImGuiCol_ResizeGripActive]  = nord9;
+		return ThemeId::Nord;
 	}
 };
-	colors[ImGuiCol_Tab]                = nord2;
+struct GruvboxTheme final : Theme {
-	colors[ImGuiCol_TabHovered]         = nord10;
+	[[nodiscard]] const char *Name() const override
-	colors[ImGuiCol_TabActive]          = nord3;
+	{
-	colors[ImGuiCol_TabUnfocused]       = nord2;
+		return "gruvbox";
-	colors[ImGuiCol_TabUnfocusedActive] = nord3;
+	}
 	// Docking colors are available only when docking branch is enabled; omit for compatibility
-	colors[ImGuiCol_TableHeaderBg]     = nord2;
+	void Apply() const override
-	colors[ImGuiCol_TableBorderStrong] = nord1;
+	{
-	colors[ImGuiCol_TableBorderLight]  = ImVec4(nord1.x, nord1.y, nord1.z, 0.6f);
+		if (gBackgroundMode == BackgroundMode::Light)
-	colors[ImGuiCol_TableRowBg]        = ImVec4(nord1.x, nord1.y, nord1.z, 0.2f);
+			ApplyGruvboxLightMediumTheme();
-	colors[ImGuiCol_TableRowBgAlt]     = ImVec4(nord1.x, nord1.y, nord1.z, 0.35f);
+		else
 			ApplyGruvboxDarkMediumTheme();
 	}
 	colors[ImGuiCol_TextSelectedBg]        = ImVec4(nord8.x, nord8.y, nord8.z, 0.35f);
 	colors[ImGuiCol_DragDropTarget]        = nord13;
 	colors[ImGuiCol_NavHighlight]          = nord9;
 	colors[ImGuiCol_NavWindowingHighlight] = ImVec4(nord6.x, nord6.y, nord6.z, 0.7f);
 	colors[ImGuiCol_NavWindowingDimBg]     = ImVec4(nord0.x, nord0.y, nord0.z, 0.6f);
 	colors[ImGuiCol_ModalWindowDimBg]      = ImVec4(nord0.x, nord0.y, nord0.z, 0.6f);
-	// Plots
+	ThemeId Id() override
-	colors[ImGuiCol_PlotLines]            = nord8;
+	{
-	colors[ImGuiCol_PlotLinesHovered]     = nord9;
+		// Legacy maps to dark; unified under base id GruvboxDarkMedium
-	colors[ImGuiCol_PlotHistogram]        = nord13;
+		return ThemeId::GruvboxDarkMedium;
-	colors[ImGuiCol_PlotHistogramHovered] = nord12;
+	}
 };
 struct EInkTheme final : Theme {
 	[[nodiscard]] const char *Name() const override
 	{
 		return "eink";
 	}
 	void Apply() const override
 	{
 		if (gBackgroundMode == BackgroundMode::Dark)
 			ApplyEInkDarkImGuiTheme();
 		else
 			ApplyEInkImGuiTheme();
 	}
 	ThemeId Id() override
 	{
 		return ThemeId::EInk;
 	}
 };
 struct SolarizedTheme final : Theme {
 	[[nodiscard]] const char *Name() const override
 	{
 		return "solarized";
 	}
 	void Apply() const override
 	{
 		if (gBackgroundMode == BackgroundMode::Light)
 			ApplySolarizedLightTheme();
 		else
 			ApplySolarizedDarkTheme();
 	}
 	ThemeId Id() override
 	{
 		return ThemeId::Solarized;
 	}
 };
 struct Plan9Theme final : Theme {
 	[[nodiscard]] const char *Name() const override
 	{
 		return "plan9";
 	}
 	void Apply() const override
 	{
 		ApplyPlan9Theme();
 	}
 	ThemeId Id() override
 	{
 		return ThemeId::Plan9;
 	}
 };
 } // namespace detail
 static const std::vector<std::unique_ptr<Theme> > &
 ThemeRegistry()
 {
 	static std::vector<std::unique_ptr<Theme> > reg;
 	if (reg.empty()) {
 		// Alphabetical by canonical name: eink, gruvbox, nord, plan9, solarized
 		reg.emplace_back(std::make_unique<detail::EInkTheme>());
 		reg.emplace_back(std::make_unique<detail::GruvboxTheme>());
 		reg.emplace_back(std::make_unique<detail::NordTheme>());
 		reg.emplace_back(std::make_unique<detail::Plan9Theme>());
 		reg.emplace_back(std::make_unique<detail::SolarizedTheme>());
 	}
 	return reg;
 }
 // Canonical theme name for a given ThemeId (via registry order)
 [[maybe_unused]] static const char *
 ThemeName(const ThemeId id)
 {
 	const auto &reg  = ThemeRegistry();
 	const size_t idx = ThemeIndexFromId(id);
 	if (idx < reg.size())
 		return reg[idx]->Name();
 	return "unknown";
 }
 // Helper to apply a theme by id and update current theme
 static void
 ApplyTheme(const ThemeId id)
 {
 	const auto &reg  = ThemeRegistry();
 	const size_t idx = ThemeIndexFromId(id);
 	if (idx < reg.size()) {
 		reg[idx]->Apply();
 		gCurrentTheme      = id;
 		gCurrentThemeIndex = idx;
 	}
 }
 [[maybe_unused]] static ThemeId
 CurrentTheme()
 {
 	return gCurrentTheme;
 }
 // Cycle helpers
 [[maybe_unused]] static ThemeId
 NextTheme()
 {
 	const auto &reg = ThemeRegistry();
 	if (reg.empty()) {
 		return gCurrentTheme;
 	}
 	const size_t nxt = (gCurrentThemeIndex + 1) % reg.size();
 	ApplyTheme(ThemeIdFromIndex(nxt));
 	return gCurrentTheme;
 }
 [[maybe_unused]] static ThemeId
 PrevTheme()
 {
 	const auto &reg = ThemeRegistry();
 	if (reg.empty()) {
 		return gCurrentTheme;
 	}
 	const size_t prv = (gCurrentThemeIndex + reg.size() - 1) % reg.size();
 	ApplyTheme(ThemeIdFromIndex(prv));
 	return gCurrentTheme;
 }
 // Name-based API
 [[maybe_unused]] static const Theme *
 GetThemeByName(const std::string &name)
 {
 	const auto &reg = ThemeRegistry();
 	for (const auto &t: reg) {
 		if (name == t->Name())
 			return t.get();
 	}
 	return nullptr;
 }
 [[maybe_unused]] static bool
 ApplyThemeByName(const std::string &name)
 {
 	// Handle aliases and background-specific names
 	std::string n = name;
 	// lowercase copy
 	std::transform(n.begin(), n.end(), n.begin(), [](unsigned char c) {
 		return static_cast<char>(std::tolower(c));
 	});
 	if (n == "gruvbox-dark") {
 		SetBackgroundMode(BackgroundMode::Dark);
 		n = "gruvbox";
 	} else if (n == "gruvbox-light") {
 		SetBackgroundMode(BackgroundMode::Light);
 		n = "gruvbox";
 	} else if (n == "solarized-dark") {
 		SetBackgroundMode(BackgroundMode::Dark);
 		n = "solarized";
 	} else if (n == "solarized-light") {
 		SetBackgroundMode(BackgroundMode::Light);
 		n = "solarized";
 	} else if (n == "eink-dark") {
 		SetBackgroundMode(BackgroundMode::Dark);
 		n = "eink";
 	} else if (n == "eink-light") {
 		SetBackgroundMode(BackgroundMode::Light);
 		n = "eink";
 	}
 	const auto &reg = ThemeRegistry();
 	for (size_t i = 0; i < reg.size(); ++i) {
 		if (n == reg[i]->Name()) {
 			reg[i]->Apply();
 			gCurrentThemeIndex = i;
 			gCurrentTheme      = ThemeIdFromIndex(i);
 			return true;
 		}
 	}
 	return false;
 }
 [[maybe_unused]] static const char *
 CurrentThemeName()
 {
 	const auto &reg = ThemeRegistry();
 	if (gCurrentThemeIndex < reg.size()) {
 		return reg[gCurrentThemeIndex]->Name();
 	}
 	return "unknown";
 }
 // Helpers to map between legacy ThemeId and registry index
 static size_t
 ThemeIndexFromId(const ThemeId id)
 {
 	switch (id) {
 	case ThemeId::EInk:
 		return 0;
 	case ThemeId::GruvboxDarkMedium:
 		return 1;
 	case ThemeId::Nord:
 		return 2;
 	case ThemeId::Plan9:
 		return 3;
 	case ThemeId::Solarized:
 		return 4;
 	}
 	return 0;
 }
 static ThemeId
 ThemeIdFromIndex(const size_t idx)
 {
 	switch (idx) {
 	default:
 	case 0:
 		return ThemeId::EInk;
 	case 1:
 		return ThemeId::GruvboxDarkMedium; // unified gruvbox
 	case 2:
 		return ThemeId::Nord;
 	case 3:
 		return ThemeId::Plan9;
 	case 4:
 		return ThemeId::Solarized;
 	}
 }
 // --- Syntax palette (v1): map TokenKind to ink color per current theme/background ---
 [[maybe_unused]] static ImVec4
 SyntaxInk(const TokenKind k)
 {
 	// Basic palettes for dark/light backgrounds; tuned for Nord-ish defaults
 	const bool dark = (GetBackgroundMode() == BackgroundMode::Dark);
 	// Base text
 	const ImVec4 def = dark ? RGBA(0xD8DEE9) : RGBA(0x2E3440);
 	switch (k) {
 	case TokenKind::Keyword:
 		return dark ? RGBA(0x81A1C1) : RGBA(0x5E81AC);
 	case TokenKind::Type:
 		return dark ? RGBA(0x8FBCBB) : RGBA(0x4C566A);
 	case TokenKind::String:
 		return dark ? RGBA(0xA3BE8C) : RGBA(0x6C8E5E);
 	case TokenKind::Char:
 		return dark ? RGBA(0xA3BE8C) : RGBA(0x6C8E5E);
 	case TokenKind::Comment:
 		return dark ? RGBA(0x616E88) : RGBA(0x7A869A);
 	case TokenKind::Number:
 		return dark ? RGBA(0xEBCB8B) : RGBA(0xB58900);
 	case TokenKind::Preproc:
 		return dark ? RGBA(0xD08770) : RGBA(0xAF3A03);
 	case TokenKind::Constant:
 		return dark ? RGBA(0xB48EAD) : RGBA(0x7B4B7F);
 	case TokenKind::Function:
 		return dark ? RGBA(0x88C0D0) : RGBA(0x3465A4);
 	case TokenKind::Operator:
 		return dark ? RGBA(0xECEFF4) : RGBA(0x2E3440);
 	case TokenKind::Punctuation:
 		return dark ? RGBA(0xECEFF4) : RGBA(0x2E3440);
 	case TokenKind::Identifier:
 		return def;
 	case TokenKind::Whitespace:
 		return def;
 	case TokenKind::Error:
 		return dark ? RGBA(0xBF616A) : RGBA(0xCC0000);
 	case TokenKind::Default: default:
 		return def;
 	}
 }
 } // namespace kte
--- a/HelpText.cc
+++ b/HelpText.cc
@@ -15,24 +15,26 @@ HelpText::Text()
 	return std::string(
 		"KTE - Kyle's Text Editor\n\n"
 		"About:\n"
-		"  kte is Kyle's Text Editor and is probably ill-suited to everyone else. It was\n"
+		"  kte is Kyle's Text Editor. It keeps a small, fast core and uses a\n"
-		"  inspired by Antirez' kilo text editor by way of someone's writeup of the\n"
+		"  WordStar/VDE-style command model with some emacs influences.\n"
 		"  process of writing a text editor from scratch. It has keybindings inspired by\n"
 		"  VDE (and the Wordstar family) and emacs; its spiritual parent is mg(1).\n"
 		"\n"
-		"Core keybindings:\n"
+		"K-commands (prefix C-k):\n"
 		"  C-k '        Toggle read-only\n"
-		"  C-k -        Unindent region\n"
+		"  C-k -        Unindent region (mark required)\n"
-		"  C-k =        Indent region\n"
+		"  C-k =        Indent region (mark required)\n"
 		"  C-k ;        Command prompt (:\\ )\n"
 		"  C-k C-d      Kill entire line\n"
 		"  C-k C-q      Quit now (no confirm)\n"
-		"  C-k a        Mark all and jump to end\n"
+		"  C-k C-x      Save and quit\n"
 		"  C-k a        Mark start of file, jump to end\n"
 		"  C-k b        Switch buffer\n"
 		"  C-k c        Close current buffer\n"
 		"  C-k d        Kill to end of line\n"
 		"  C-k e        Open file (prompt)\n"
 		"  C-k f        Flush kill ring\n"
 		"  C-k g        Jump to line\n"
 		"  C-k h        Show this help\n"
 		"  C-k j        Jump to mark\n"
 		"  C-k l        Reload buffer from disk\n"
 		"  C-k n        Previous buffer\n"
 		"  C-k o        Change working directory (prompt)\n"
@@ -44,12 +46,36 @@ HelpText::Text()
 		"  C-k v        Toggle visual file picker (GUI)\n"
 		"  C-k w        Show working directory\n"
 		"  C-k x        Save and quit\n"
 		"  C-k y        Yank\n"
 		"\n"
 		"ESC/Alt commands:\n"
 		"  ESC <        Go to beginning of file\n"
 		"  ESC >        Go to end of file\n"
 		"  ESC m        Toggle mark\n"
 		"  ESC w        Copy region to kill ring (Alt-w)\n"
 		"  ESC b        Previous word\n"
 		"  ESC f        Next word\n"
 		"  ESC d        Delete next word (Alt-d)\n"
 		"  ESC BACKSPACE Delete previous word (Alt-Backspace)\n"
 		"  ESC q        Reflow paragraph\n"
-		"  ESC BACKSPACE Delete previous word\n"
+		"\n"
-		"  ESC d        Delete next word\n"
+		"Control keys:\n"
-		"  Alt-w        Copy region to kill ring\n\n"
+		"  C-a C-e      Line start / end\n"
-		"Buffers:\n  +HELP+ is read-only. Press C-k ' to toggle if you need to edit; C-k h restores it.\n"
+		"  C-b C-f      Move left / right\n"
 		"  C-n C-p      Move down / up\n"
 		"  C-d          Delete char\n"
 		"  C-w / C-y    Kill region / Yank\n"
 		"  C-s          Incremental find\n"
 		"  C-r          Regex search\n"
 		"  C-t          Regex search & replace\n"
 		"  C-h          Search & replace\n"
 		"  C-l / C-g    Refresh / Cancel\n"
 		"  C-u [digits] Universal argument (repeat count)\n"
 		"\n"
 		"Buffers:\n  +HELP+ is read-only. Press C-k ' to toggle; C-k h restores it.\n"
 		"\n"
 		"GUI appearance (command prompt):\n"
 		"  : theme NAME         Set GUI theme (eink, gruvbox, nord, plan9, solarized)\n"
 		"  : background MODE    Set background: light | dark (affects eink, gruvbox, solarized)\n"
 	);
 }
--- a/Highlight.h
+++ b/Highlight.h
@@ -0,0 +1,37 @@
 // Highlight.h - core syntax highlighting types for kte
 #pragma once
 #include <cstdint>
 #include <vector>
 namespace kte {
 // Token kinds shared between renderers and highlighters
 enum class TokenKind {
 	Default,
 	Keyword,
 	Type,
 	String,
 	Char,
 	Comment,
 	Number,
 	Preproc,
 	Constant,
 	Function,
 	Operator,
 	Punctuation,
 	Identifier,
 	Whitespace,
 	Error
 };
 struct HighlightSpan {
 	int col_start{0}; // inclusive, 0-based columns in buffer indices
 	int col_end{0}; // exclusive
 	TokenKind kind{TokenKind::Default};
 };
 struct LineHighlight {
 	std::vector<HighlightSpan> spans;
 	std::uint64_t version{0}; // buffer version used for this line
 };
 } // namespace kte
--- a/KKeymap.cc
+++ b/KKeymap.cc
@@ -108,6 +108,9 @@ KLookupKCommand(const int ascii_key, const bool ctrl, CommandId &out) -> bool
 	case '=':
 		out = CommandId::IndentRegion;
 		return true;
 	case ';':
 		out = CommandId::CommandPromptStart; // C-k ; : generic command prompt
 		return true;
 	default:
 		break;
 	}
--- a/ROADMAP.md
+++ b/ROADMAP.md
@@ -2,9 +2,11 @@ ROADMAP / TODO:
 - [x] Search + Replace
 - [x] Regex search + replace
 - [ ] The undo system should actually work
 - [x] Able to mark buffers as read-only
 - [x] Built-in help text
 - [x] Shorten paths in the homedir with ~
 - [x] When the filename is longer than the message window, scoot left to
  keep it in view
 - [x] Syntax highlighting
 - [ ] The undo system should actually work
 - [ ] LSP integration
--- a/TerminalRenderer.cc
+++ b/TerminalRenderer.cc
@@ -9,6 +9,7 @@
 #include "TerminalRenderer.h"
 #include "Buffer.h"
 #include "Editor.h"
 #include "Highlight.h"
 // Version string expected to be provided by build system as KTE_VERSION_STR
 #ifndef KTE_VERSION_STR
@@ -41,6 +42,13 @@ TerminalRenderer::Draw(Editor &ed)
 		std::size_t coloffs = buf->Coloffs();
 		const int tabw = 8;
 		// Phase 3: prefetch visible viewport highlights (current terminal area)
 		if (buf->SyntaxEnabled() && buf->Highlighter() && buf->Highlighter()->HasHighlighter()) {
 			int fr = static_cast<int>(rowoffs);
 			int rc = std::max(0, content_rows);
 			buf->Highlighter()->PrefetchViewport(*buf, fr, rc, buf->Version());
 		}
 		for (int r = 0; r < content_rows; ++r) {
 			move(r, 0);
 			std::size_t li         = rowoffs + static_cast<std::size_t>(r);
@@ -52,7 +60,9 @@ TerminalRenderer::Draw(Editor &ed)
 			if (search_mode && li < lines.size()) {
 				std::string sline = static_cast<std::string>(lines[li]);
 				// If regex search prompt is active (RegexSearch or RegexReplaceFind), use regex to compute highlight ranges
-                if (ed.PromptActive() && (ed.CurrentPromptKind() == Editor::PromptKind::RegexSearch || ed.CurrentPromptKind() == Editor::PromptKind::RegexReplaceFind)) {
+				if (ed.PromptActive() && (
 					    ed.CurrentPromptKind() == Editor::PromptKind::RegexSearch || ed.
 					    CurrentPromptKind() == Editor::PromptKind::RegexReplaceFind)) {
 					try {
 						std::regex rx(ed.SearchQuery());
 						for (auto it = std::sregex_iterator(sline.begin(), sline.end(), rx);
@@ -75,12 +85,15 @@ TerminalRenderer::Draw(Editor &ed)
 				}
 			}
 			auto is_src_in_hl = [&](std::size_t si) -> bool {
-                if (ranges.empty()) return false;
+				if (ranges.empty())
 					return false;
 				// ranges are non-overlapping and ordered by construction
 				// linear scan is fine for now
 				for (const auto &rg: ranges) {
-                    if (si < rg.first) break;
+					if (si < rg.first)
-                    if (si >= rg.first && si < rg.second) return true;
+						break;
 					if (si >= rg.first && si < rg.second)
 						return true;
 				}
 				return false;
 			};
@@ -96,6 +109,46 @@ TerminalRenderer::Draw(Editor &ed)
 				std::string line = static_cast<std::string>(lines[li]);
 				src_i            = 0;
 				render_col       = 0;
 				// Syntax highlighting: fetch per-line spans
 				const kte::LineHighlight *lh_ptr = nullptr;
 				if (buf->SyntaxEnabled() && buf->Highlighter() && buf->Highlighter()->
 				    HasHighlighter()) {
 					lh_ptr = &buf->Highlighter()->GetLine(
 						*buf, static_cast<int>(li), buf->Version());
 				}
 				auto token_at = [&](std::size_t src_index) -> kte::TokenKind {
 					if (!lh_ptr)
 						return kte::TokenKind::Default;
 					for (const auto &sp: lh_ptr->spans) {
 						if (static_cast<int>(src_index) >= sp.col_start && static_cast<int>(
 							    src_index) < sp.col_end)
 							return sp.kind;
 					}
 					return kte::TokenKind::Default;
 				};
 				auto apply_token_attr = [&](kte::TokenKind k) {
 					// Map to simple attributes; search highlight uses A_STANDOUT which takes precedence below
 					attrset(A_NORMAL);
 					switch (k) {
 					case kte::TokenKind::Keyword:
 					case kte::TokenKind::Type:
 					case kte::TokenKind::Constant:
 					case kte::TokenKind::Function:
 						attron(A_BOLD);
 						break;
 					case kte::TokenKind::Comment:
 						attron(A_DIM);
 						break;
 					case kte::TokenKind::String:
 					case kte::TokenKind::Char:
 					case kte::TokenKind::Number:
 						// standout a bit using A_UNDERLINE if available
 						attron(A_UNDERLINE);
 						break;
 					default:
 						break;
 					}
 				};
 				while (written < cols) {
 					char ch       = ' ';
 					bool from_src = false;
@@ -119,15 +172,35 @@ TerminalRenderer::Draw(Editor &ed)
 							// Now render visible spaces
 							while (next_tab > 0 && written < cols) {
 								bool in_hl  = search_mode && is_src_in_hl(src_i);
-                                bool in_cur = has_current && li == cur_my && src_i >= cur_mx && src_i < cur_mend;
+								bool in_cur =
 									has_current && li == cur_my && src_i >= cur_mx
 									&& src_i < cur_mend;
 								// Toggle highlight attributes
 								int attr = 0;
-                                if (in_hl) attr |= A_STANDOUT;
+								if (in_hl)
-                                if (in_cur) attr |= A_BOLD;
+									attr |= A_STANDOUT;
-                                if ((attr & A_STANDOUT) && !hl_on) { attron(A_STANDOUT); hl_on = true; }
+								if (in_cur)
-                                if (!(attr & A_STANDOUT) && hl_on) { attroff(A_STANDOUT); hl_on = false; }
+									attr |= A_BOLD;
-                                if ((attr & A_BOLD) && !cur_on) { attron(A_BOLD); cur_on = true; }
+								if ((attr & A_STANDOUT) && !hl_on) {
-                                if (!(attr & A_BOLD) && cur_on) { attroff(A_BOLD); cur_on = false; }
+									attron(A_STANDOUT);
 									hl_on = true;
 								}
 								if (!(attr & A_STANDOUT) && hl_on) {
 									attroff(A_STANDOUT);
 									hl_on = false;
 								}
 								if ((attr & A_BOLD) && !cur_on) {
 									attron(A_BOLD);
 									cur_on = true;
 								}
 								if (!(attr & A_BOLD) && cur_on) {
 									attroff(A_BOLD);
 									cur_on = false;
 								}
 								// Apply syntax attribute only if not in search highlight
 								if (!in_hl) {
 									apply_token_attr(token_at(src_i));
 								}
 								addch(' ');
 								++written;
 								++render_col;
@@ -151,11 +224,28 @@ TerminalRenderer::Draw(Editor &ed)
 						from_src = false;
 					}
 					bool in_hl  = search_mode && from_src && is_src_in_hl(src_i);
-                    bool in_cur = has_current && li == cur_my && from_src && src_i >= cur_mx && src_i < cur_mend;
+					bool in_cur =
-                    if (in_hl && !hl_on) { attron(A_STANDOUT); hl_on = true; }
+						has_current && li == cur_my && from_src && src_i >= cur_mx && src_i <
-                    if (!in_hl && hl_on) { attroff(A_STANDOUT); hl_on = false; }
+						cur_mend;
-                    if (in_cur && !cur_on) { attron(A_BOLD); cur_on = true; }
+					if (in_hl && !hl_on) {
-                    if (!in_cur && cur_on) { attroff(A_BOLD); cur_on = false; }
+						attron(A_STANDOUT);
 						hl_on = true;
 					}
 					if (!in_hl && hl_on) {
 						attroff(A_STANDOUT);
 						hl_on = false;
 					}
 					if (in_cur && !cur_on) {
 						attron(A_BOLD);
 						cur_on = true;
 					}
 					if (!in_cur && cur_on) {
 						attroff(A_BOLD);
 						cur_on = false;
 					}
 					if (!in_hl && from_src) {
 						apply_token_attr(token_at(src_i));
 					}
 					addch(static_cast<unsigned char>(ch));
 					++written;
 					++render_col;
@@ -173,6 +263,7 @@ TerminalRenderer::Draw(Editor &ed)
 				attroff(A_BOLD);
 				cur_on = false;
 			}
 			attrset(A_NORMAL);
 			clrtoeol();
 		}
@@ -222,11 +313,14 @@ TerminalRenderer::Draw(Editor &ed)
 		}
 		// Prefer keeping the tail of the filename visible when it exceeds the window
 		std::string msg;
-     if (!label.empty()) {
+		if (kind == Editor::PromptKind::Command) {
 			msg = ": ";
 		} else if (!label.empty()) {
 			msg = label + ": ";
 		}
 		// When dealing with file-related prompts, left-trim the filename text so the tail stays visible
-     if ((kind == Editor::PromptKind::OpenFile || kind == Editor::PromptKind::SaveAs || kind == Editor::PromptKind::Chdir) && cols > 0) {
+		if ((kind == Editor::PromptKind::OpenFile || kind == Editor::PromptKind::SaveAs || kind ==
 		     Editor::PromptKind::Chdir) && cols > 0) {
 			int avail = cols - static_cast<int>(msg.size());
 			if (avail <= 0) {
 				// No room for label; fall back to showing the rightmost portion of the whole string
--- a/UndoSystem.cc
+++ b/UndoSystem.cc
@@ -338,31 +338,42 @@ UndoSystem::UpdateBufferReference(Buffer &new_buf)
 	buf_ = &new_buf;
 }
 // ---- Debug helpers ----
 const char *
 UndoSystem::type_str(UndoType t)
 {
 	switch (t) {
-    case UndoType::Insert: return "Insert";
+	case UndoType::Insert:
-    case UndoType::Delete: return "Delete";
+		return "Insert";
-    case UndoType::Paste: return "Paste";
+	case UndoType::Delete:
-    case UndoType::Newline: return "Newline";
+		return "Delete";
-    case UndoType::DeleteRow: return "DeleteRow";
+	case UndoType::Paste:
 		return "Paste";
 	case UndoType::Newline:
 		return "Newline";
 	case UndoType::DeleteRow:
 		return "DeleteRow";
 	}
 	return "?";
 }
 bool
 UndoSystem::is_descendant(UndoNode *root, const UndoNode *target)
 {
-    if (!root || !target) return false;
+	if (!root || !target)
-    if (root == target) return true;
+		return false;
 	if (root == target)
 		return true;
 	for (UndoNode *child = root->child; child != nullptr; child = child->next) {
-        if (is_descendant(child, target)) return true;
+		if (is_descendant(child, target))
 			return true;
 	}
 	return false;
 }
 void
 UndoSystem::debug_log(const char *op) const
 {
--- a/UndoSystem.h
+++ b/UndoSystem.h
@@ -43,7 +43,9 @@ private:
 	// Debug helpers (compiled only when KTE_UNDO_DEBUG is defined)
 	void debug_log(const char *op) const;
 	static const char *type_str(UndoType t);
 	static bool is_descendant(UndoNode *root, const UndoNode *target);
 	void update_dirty_flag();
--- a/docs/kge.1
+++ b/docs/kge.1
@@ -1,7 +1,7 @@
 .\" kge(1) — Kyle's Graphical Editor (GUI-first)
 .\"
 .\" Project homepage: https://github.com/wntrmute/kte
-.TH KGE 1 "2025-11-30" "kte 0.1.0" "User Commands"
+.TH KGE 1 "2025-12-01" "kte 0.1.0" "User Commands"
 .SH NAME
 kge \- Kyle's Graphical Editor (GUI-first)
 .SH SYNOPSIS
@@ -52,11 +52,8 @@ tree for the canonical reference and notes:
 .PP
 Enter K-command mode with Ctrl-K. Exit K-command mode with ESC or Ctrl-G.
 .TP
-.B C-k BACKSPACE
+.B C-k '
-Delete from the cursor to the beginning of the line.
+Toggle read-only for the current buffer.
 .TP
 .B C-k SPACE
 Toggle the mark.
 .TP
 .B C-k -
 If the mark is set, unindent the region.
@@ -64,6 +61,9 @@ If the mark is set, unindent the region.
 .B C-k =
 If the mark is set, indent the region.
 .TP
 .B C-k ;
 Open the generic command prompt (": ").
 .TP
 .B C-k a
 Set the mark at the beginning of the file, then jump to the end of the file.
 .TP
@@ -80,7 +80,7 @@ Delete from the cursor to the end of the line.
 Delete the entire line.
 .TP
 .B C-k e
-Edit a new file.
+Edit (open) a new file.
 .TP
 .B C-k f
 Flush the kill ring.
@@ -88,14 +88,20 @@ Flush the kill ring.
 .B C-k g
 Go to a specific line.
 .TP
 .B C-k h
 Show the built-in help (+HELP+ buffer).
 .TP
 .B C-k j
 Jump to the mark.
 .TP
 .B C-k l
 Reload the current buffer from disk.
 .TP
-.B C-k m
+.B C-k n
-Run make(1), reporting success or failure.
+Switch to the previous buffer.
 .TP
 .B C-k o
 Change working directory (prompt).
 .TP
 .B C-k p
 Switch to the next buffer.
@@ -106,14 +112,20 @@ Exit the editor. If the file has unsaved changes, a warning will be printed; a s
 .B C-k C-q
 Immediately exit the editor.
 .TP
 .B C-k r
 Redo changes.
 .TP
 .B C-k s
 Save the file, prompting for a filename if needed.
 .TP
 .B C-k u
 Undo.
 .TP
-.B C-k r
+.B C-k v
-Redo changes.
+Toggle visual file picker (GUI).
 .TP
 .B C-k w
 Show the current working directory.
 .TP
 .B C-k x
 Save the file and exit. Also C-k C-x.
@@ -121,23 +133,50 @@ Save the file and exit. Also C-k C-x.
 .B C-k y
 Yank the kill ring.
 .TP
-.B C-k \e
+.B C-k C-x
-Dump core.
+Save the file and exit.
 .SS Other keybindings
 .TP
 .B C-g
 Cancel the current operation.
 .TP
 .B C-a
 Move to the beginning of the line.
 .TP
 .B C-e
 Move to the end of the line.
 .TP
 .B C-b
 Move left.
 .TP
 .B C-f
 Move right.
 .TP
 .B C-n
 Move down.
 .TP
 .B C-p
 Move up.
 .TP
 .B C-l
 Refresh the display.
 .TP
 .B C-d
 Delete the character at the cursor.
 .TP
 .B C-r
 Regex search.
 .TP
 .B C-s
 Incremental find.
 .TP
 .B C-t
 Regex search and replace.
 .TP
 .B C-h
 Search and replace.
 .TP
 .B C-u
 Universal argument. C-u followed by numbers will repeat an operation n times.
 .TP
@@ -147,6 +186,15 @@ Kill the region if the mark is set.
 .B C-y
 Yank the kill ring.
 .TP
 .B ESC <
 Move to the beginning of the file.
 .TP
 .B ESC >
 Move to the end of the file.
 .TP
 .B ESC m
 Toggle the mark.
 .TP
 .B ESC BACKSPACE
 Delete the previous word.
 .TP
--- a/docs/kte.1
+++ b/docs/kte.1
@@ -1,7 +1,7 @@
 .\" kte(1) — Kyle's Text Editor (terminal-first)
 .\"
 .\" Project homepage: https://github.com/wntrmute/kte
-.TH KTE 1 "2025-11-30" "kte 0.1.0" "User Commands"
+.TH KTE 1 "2025-12-01" "kte 0.1.0" "User Commands"
 .SH NAME
 kte \- Kyle's Text Editor (terminal-first)
 .SH SYNOPSIS
@@ -57,11 +57,8 @@ in the source tree for the canonical reference and notes.
 .PP
 Enter K-command mode with Ctrl-K. Exit K-command mode with ESC or Ctrl-G.
 .TP
-.B C-k BACKSPACE
+.B C-k '
-Delete from the cursor to the beginning of the line.
+Toggle read-only for the current buffer.
 .TP
 .B C-k SPACE
 Toggle the mark.
 .TP
 .B C-k -
 If the mark is set, unindent the region.
@@ -69,6 +66,9 @@ If the mark is set, unindent the region.
 .B C-k =
 If the mark is set, indent the region.
 .TP
 .B C-k ;
 Open the generic command prompt (": ").
 .TP
 .B C-k a
 Set the mark at the beginning of the file, then jump to the end of the file.
 .TP
@@ -85,7 +85,7 @@ Delete from the cursor to the end of the line.
 Delete the entire line.
 .TP
 .B C-k e
-Edit a new file.
+Edit (open) a new file.
 .TP
 .B C-k f
 Flush the kill ring.
@@ -93,14 +93,20 @@ Flush the kill ring.
 .B C-k g
 Go to a specific line.
 .TP
 .B C-k h
 Show the built-in help (+HELP+ buffer).
 .TP
 .B C-k j
 Jump to the mark.
 .TP
 .B C-k l
 Reload the current buffer from disk.
 .TP
-.B C-k m
+.B C-k n
-Run make(1), reporting success or failure.
+Switch to the previous buffer.
 .TP
 .B C-k o
 Change working directory (prompt).
 .TP
 .B C-k p
 Switch to the next buffer.
@@ -111,14 +117,20 @@ Exit the editor. If the file has unsaved changes, a warning will be printed; a s
 .B C-k C-q
 Immediately exit the editor.
 .TP
 .B C-k r
 Redo changes.
 .TP
 .B C-k s
 Save the file, prompting for a filename if needed.
 .TP
 .B C-k u
 Undo.
 .TP
-.B C-k r
+.B C-k v
-Redo changes.
+Toggle visual file picker (GUI).
 .TP
 .B C-k w
 Show the current working directory.
 .TP
 .B C-k x
 Save the file and exit. Also C-k C-x.
@@ -126,23 +138,76 @@ Save the file and exit. Also C-k C-x.
 .B C-k y
 Yank the kill ring.
 .TP
-.B C-k \e
+.B C-k C-x
-Dump core.
+Save the file and exit.
 .SH GUI APPEARANCE
 When running the GUI frontend, you can control appearance via the generic
 command prompt (type "C-k ;" then enter commands):
 .TP
 .B : theme NAME
 Set the GUI theme. Available names: "nord", "gruvbox", "plan9", "solarized", "eink".
 Compatibility aliases are also accepted: "gruvbox-dark", "gruvbox-light",
 "solarized-dark", "solarized-light", "eink-dark", "eink-light".
 .TP
 .B : background MODE
 Set background mode for supported themes. MODE is either "light" or "dark".
 Themes that respond to background: eink, gruvbox, solarized. The
 "nord" and "plan9" themes do not vary with background.
 .SH CONFIGURATION
 The GUI reads a simple configuration file at
 ~/.config/kte/kge.ini. Recognized keys include:
 .IP "fullscreen=on|off"
 .IP "columns=NUM"
 .IP "rows=NUM"
 .IP "font_size=NUM"
 .IP "theme=NAME"
 .IP "background=light|dark"
 The theme name accepts the values listed above. The background key controls
 light/dark variants when the selected theme supports it.
 .SS Other keybindings
 .TP
 .B C-g
 Cancel the current operation.
 .TP
 .B C-a
 Move to the beginning of the line.
 .TP
 .B C-e
 Move to the end of the line.
 .TP
 .B C-b
 Move left.
 .TP
 .B C-f
 Move right.
 .TP
 .B C-n
 Move down.
 .TP
 .B C-p
 Move up.
 .TP
 .B C-l
 Refresh the display.
 .TP
 .B C-d
 Delete the character at the cursor.
 .TP
 .B C-r
 Regex search.
 .TP
 .B C-s
 Incremental find.
 .TP
 .B C-t
 Regex search and replace.
 .TP
 .B C-h
 Search and replace.
 .TP
 .B C-u
 Universal argument. C-u followed by numbers will repeat an operation n times.
 .TP
@@ -152,6 +217,15 @@ Kill the region if the mark is set.
 .B C-y
 Yank the kill ring.
 .TP
 .B ESC <
 Move to the beginning of the file.
 .TP
 .B ESC >
 Move to the end of the file.
 .TP
 .B ESC m
 Toggle the mark.
 .TP
 .B ESC BACKSPACE
 Delete the previous word.
 .TP
--- a/docs/lsp
+++ b/docs/lsp
@@ -0,0 +1,525 @@
 # LSP Support Implementation Plan for kte
 ## Executive Summary
 This plan outlines a comprehensive approach to integrating Language Server Protocol (LSP) support into kte while
 respecting its core architectural principles: **frontend/backend separation**, **testability**, and **dual terminal/GUI
 support**.
 ---
 ## 1. Core Architecture
 ### 1.1 LSP Client Module Structure
 ```c++
 // LspClient.h - Core LSP client abstraction
 class LspClient {
 public:
    virtual ~LspClient() = default;
    // Lifecycle
    virtual bool initialize(const std::string& rootPath) = 0;
    virtual void shutdown() = 0;
    // Document Synchronization
    virtual void didOpen(const std::string& uri, const std::string& languageId, 
                         int version, const std::string& text) = 0;
    virtual void didChange(const std::string& uri, int version, 
                           const std::vector<TextDocumentContentChangeEvent>& changes) = 0;
    virtual void didClose(const std::string& uri) = 0;
    virtual void didSave(const std::string& uri) = 0;
    // Language Features
    virtual void completion(const std::string& uri, Position pos, 
                           CompletionCallback callback) = 0;
    virtual void hover(const std::string& uri, Position pos, 
                      HoverCallback callback) = 0;
    virtual void definition(const std::string& uri, Position pos, 
                           LocationCallback callback) = 0;
    virtual void references(const std::string& uri, Position pos, 
                           LocationsCallback callback) = 0;
    virtual void diagnostics(DiagnosticsCallback callback) = 0;
    // Process Management
    virtual bool isRunning() const = 0;
    virtual std::string getServerName() const = 0;
 };
 ```
 ### 1.2 Process-based LSP Implementation
 ```c++
 // LspProcessClient.h - Manages LSP server subprocess
 class LspProcessClient : public LspClient {
 private:
    std::string serverCommand_;
    std::vector<std::string> serverArgs_;
    std::unique_ptr<Process> process_;
    std::unique_ptr<JsonRpcTransport> transport_;
    std::unordered_map<int, PendingRequest> pendingRequests_;
    int nextRequestId_ = 1;
    // Async I/O handling
    std::thread readerThread_;
    std::mutex mutex_;
    std::condition_variable cv_;
 public:
    LspProcessClient(const std::string& command, 
                     const std::vector<std::string>& args);
    // ... implementation of LspClient interface
 };
 ```
 ### 1.3 JSON-RPC Transport Layer
 ```c++
 // JsonRpcTransport.h
 class JsonRpcTransport {
 public:
    // Send a request and get the request ID
    int sendRequest(const std::string& method, const nlohmann::json& params);
    // Send a notification (no response expected)
    void sendNotification(const std::string& method, const nlohmann::json& params);
    // Read next message (blocking)
    std::optional<JsonRpcMessage> readMessage();
 private:
    void writeMessage(const nlohmann::json& message);
    std::string readContentLength();
    int fdIn_;   // stdin to server
    int fdOut_;  // stdout from server
 };
 ```
 ---
 ## 2. Incremental Document Updates
 ### 2.1 Change Tracking in Buffer
 The key to efficient LSP integration is tracking changes incrementally. This integrates with the existing `Buffer`
 class:
 ```c++
 // TextDocumentContentChangeEvent.h
 struct TextDocumentContentChangeEvent {
    std::optional<Range> range;     // If nullopt, entire document changed
    std::optional<int> rangeLength; // Deprecated but some servers use it
    std::string text;
 };
 // BufferChangeTracker.h - Integrates with Buffer to track changes
 class BufferChangeTracker {
 public:
    explicit BufferChangeTracker(Buffer* buffer);
    // Called by Buffer on each edit operation
    void recordInsertion(Position pos, const std::string& text);
    void recordDeletion(Range range, const std::string& deletedText);
    // Get accumulated changes since last sync
    std::vector<TextDocumentContentChangeEvent> getChanges();
    // Clear changes after sending to LSP
    void clearChanges();
    // Get current document version
    int getVersion() const { return version_; }
 private:
    Buffer* buffer_;
    int version_ = 0;
    std::vector<TextDocumentContentChangeEvent> pendingChanges_;
    // Optional: Coalesce adjacent changes
    void coalesceChanges();
 };
 ```
 ### 2.2 Integration with Buffer Operations
 ```c++
 // Buffer.h additions
 class Buffer {
    // ... existing code ...
    // LSP integration
    void setChangeTracker(std::unique_ptr<BufferChangeTracker> tracker);
    BufferChangeTracker* getChangeTracker() { return changeTracker_.get(); }
    // These methods should call tracker when present
    void insertText(Position pos, const std::string& text);
    void deleteRange(Range range);
 private:
    std::unique_ptr<BufferChangeTracker> changeTracker_;
 };
 ```
 ### 2.3 Sync Strategy Selection
 ```c++
 // LspSyncMode.h
 enum class LspSyncMode {
    None,        // No sync
    Full,        // Send full document on each change
    Incremental  // Send only changes (preferred)
 };
 // Determined during server capability negotiation
 LspSyncMode negotiateSyncMode(const ServerCapabilities& caps);
 ```
 ---
 ## 3. Diagnostics Display System
 ### 3.1 Diagnostic Data Model
 ```c++
 // Diagnostic.h
 enum class DiagnosticSeverity {
    Error = 1,
    Warning = 2,
    Information = 3,
    Hint = 4
 };
 struct Diagnostic {
    Range range;
    DiagnosticSeverity severity;
    std::optional<std::string> code;
    std::optional<std::string> source;
    std::string message;
    std::vector<DiagnosticRelatedInformation> relatedInfo;
 };
 // DiagnosticStore.h - Central storage for diagnostics
 class DiagnosticStore {
 public:
    void setDiagnostics(const std::string& uri, 
                        std::vector<Diagnostic> diagnostics);
    const std::vector<Diagnostic>& getDiagnostics(const std::string& uri) const;
    std::vector<Diagnostic> getDiagnosticsAtLine(const std::string& uri, 
                                                  int line) const;
    std::optional<Diagnostic> getDiagnosticAtPosition(const std::string& uri,
                                                       Position pos) const;
    void clear(const std::string& uri);
    void clearAll();
    // Statistics
    int getErrorCount(const std::string& uri) const;
    int getWarningCount(const std::string& uri) const;
 private:
    std::unordered_map<std::string, std::vector<Diagnostic>> diagnostics_;
 };
 ```
 ### 3.2 Frontend-Agnostic Diagnostic Display Interface
 Following kte's existing abstraction pattern with `Frontend`, `Renderer`, and `InputHandler`:
 ```c++
 // DiagnosticDisplay.h - Abstract interface for showing diagnostics
 class DiagnosticDisplay {
 public:
    virtual ~DiagnosticDisplay() = default;
    // Update the diagnostic indicators for a buffer
    virtual void updateDiagnostics(const std::string& uri, 
                                   const std::vector<Diagnostic>& diagnostics) = 0;
    // Show inline diagnostic at cursor position
    virtual void showInlineDiagnostic(const Diagnostic& diagnostic) = 0;
    // Show diagnostic list/panel
    virtual void showDiagnosticList(const std::vector<Diagnostic>& diagnostics) = 0;
    virtual void hideDiagnosticList() = 0;
    // Status bar summary
    virtual void updateStatusBar(int errorCount, int warningCount) = 0;
 };
 ```
 ### 3.3 Terminal Diagnostic Display
 ```c++
 // TerminalDiagnosticDisplay.h
 class TerminalDiagnosticDisplay : public DiagnosticDisplay {
 public:
    explicit TerminalDiagnosticDisplay(TerminalRenderer* renderer);
    void updateDiagnostics(const std::string& uri, 
                          const std::vector<Diagnostic>& diagnostics) override;
    void showInlineDiagnostic(const Diagnostic& diagnostic) override;
    void showDiagnosticList(const std::vector<Diagnostic>& diagnostics) override;
    void hideDiagnosticList() override;
    void updateStatusBar(int errorCount, int warningCount) override;
 private:
    TerminalRenderer* renderer_;
    // Terminal-specific display strategies
    void renderGutterMarkers(const std::vector<Diagnostic>& diagnostics);
    void renderUnderlines(const std::vector<Diagnostic>& diagnostics);
    void renderVirtualText(const Diagnostic& diagnostic);
 };
 ```
 **Terminal Display Strategies:**
 1. **Gutter markers**: Show `E` (error), `W` (warning), `I` (info), `H` (hint) in left gutter
 2. **Underlines**: Use terminal underline/curly underline capabilities (where supported)
 3. **Virtual text**: Display diagnostic message at end of line (configurable)
 4. **Status line**: `[E:3 W:5]` summary
 5. **Message line**: Full diagnostic on cursor line shown in bottom bar
 ```
 1 │ fn main() {
 E 2 │     let x: i32 = "hello";
  3 │ }                        
 ──────────────────────────────────────
 error[E0308]: mismatched types       
 expected `i32`, found `&str`         
 [E:1 W:0] main.rs
 ```
 ### 3.4 GUI Diagnostic Display
 ```c++
 // GUIDiagnosticDisplay.h
 class GUIDiagnosticDisplay : public DiagnosticDisplay {
 public:
    explicit GUIDiagnosticDisplay(GUIRenderer* renderer, GUITheme* theme);
    void updateDiagnostics(const std::string& uri, 
                          const std::vector<Diagnostic>& diagnostics) override;
    void showInlineDiagnostic(const Diagnostic& diagnostic) override;
    void showDiagnosticList(const std::vector<Diagnostic>& diagnostics) override;
    void hideDiagnosticList() override;
    void updateStatusBar(int errorCount, int warningCount) override;
 private:
    GUIRenderer* renderer_;
    GUITheme* theme_;
    // GUI-specific display
    void renderWavyUnderlines(const std::vector<Diagnostic>& diagnostics);
    void renderTooltip(Position pos, const Diagnostic& diagnostic);
    void renderDiagnosticPanel();
 };
 ```
 **GUI Display Features:**
 1. **Wavy underlines**: Classic IDE-style (red for errors, yellow for warnings, etc.)
 2. **Gutter icons**: Colored icons/dots in the gutter
 3. **Hover tooltips**: Rich tooltips on hover showing full diagnostic
 4. **Diagnostic panel**: Bottom panel with clickable diagnostic list
 5. **Minimap markers**: Colored marks on the minimap (if present)
 ---
 ## 4. LspManager - Central Coordination
 ```c++
 // LspManager.h
 class LspManager {
 public:
    explicit LspManager(Editor* editor, DiagnosticDisplay* display);
    // Server management
    void registerServer(const std::string& languageId, 
                       const LspServerConfig& config);
    bool startServerForBuffer(Buffer* buffer);
    void stopServer(const std::string& languageId);
    void stopAllServers();
    // Document sync
    void onBufferOpened(Buffer* buffer);
    void onBufferChanged(Buffer* buffer);
    void onBufferClosed(Buffer* buffer);
    void onBufferSaved(Buffer* buffer);
    // Feature requests
    void requestCompletion(Buffer* buffer, Position pos, 
                          CompletionCallback callback);
    void requestHover(Buffer* buffer, Position pos, 
                     HoverCallback callback);
    void requestDefinition(Buffer* buffer, Position pos, 
                          LocationCallback callback);
    // Configuration
    void setDebugLogging(bool enabled);
 private:
    Editor* editor_;
    DiagnosticDisplay* display_;
    DiagnosticStore diagnosticStore_;
    std::unordered_map<std::string, std::unique_ptr<LspClient>> servers_;
    std::unordered_map<std::string, LspServerConfig> serverConfigs_;
    void handleDiagnostics(const std::string& uri, 
                          const std::vector<Diagnostic>& diagnostics);
    std::string getLanguageId(Buffer* buffer);
    std::string getUri(Buffer* buffer);
 };
 ```
 ---
 ## 5. Configuration
 ```c++
 // LspServerConfig.h
 struct LspServerConfig {
    std::string command;
    std::vector<std::string> args;
    std::vector<std::string> filePatterns;  // e.g., {"*.rs", "*.toml"}
    std::string rootPatterns;               // e.g., "Cargo.toml"
    LspSyncMode preferredSyncMode = LspSyncMode::Incremental;
    bool autostart = true;
    std::unordered_map<std::string, nlohmann::json> initializationOptions;
    std::unordered_map<std::string, nlohmann::json> settings;
 };
 // Default configurations
 std::vector<LspServerConfig> getDefaultServerConfigs() {
    return {
        {
            .command = "rust-analyzer",
            .filePatterns = {"*.rs"},
            .rootPatterns = "Cargo.toml"
        },
        {
            .command = "clangd",
            .args = {"--background-index"},
            .filePatterns = {"*.c", "*.cc", "*.cpp", "*.h", "*.hpp"},
            .rootPatterns = "compile_commands.json"
        },
        {
            .command = "gopls",
            .filePatterns = {"*.go"},
            .rootPatterns = "go.mod"
        },
        // ... more servers
    };
 }
 ```
 ---
 ## 6. Implementation Phases
 ### Phase 1: Foundation (2-3 weeks)
 - [ ] JSON-RPC transport layer
 - [ ] Process management for LSP servers
 - [ ] Basic `LspClient` with initialize/shutdown
 - [ ] `textDocument/didOpen`, `textDocument/didClose` (full sync)
 ### Phase 2: Incremental Sync (1-2 weeks)
 - [ ] `BufferChangeTracker` integration with `Buffer`
 - [ ] `textDocument/didChange` with incremental updates
 - [ ] Change coalescing for rapid edits
 - [ ] Version tracking
 ### Phase 3: Diagnostics (2-3 weeks)
 - [ ] `DiagnosticStore` implementation
 - [ ] `TerminalDiagnosticDisplay` with gutter markers & status line
 - [ ] `GUIDiagnosticDisplay` with wavy underlines & tooltips
 - [ ] `textDocument/publishDiagnostics` handling
 ### Phase 4: Language Features (3-4 weeks)
 - [ ] Completion (`textDocument/completion`)
 - [ ] Hover (`textDocument/hover`)
 - [ ] Go to definition (`textDocument/definition`)
 - [ ] Find references (`textDocument/references`)
 - [ ] Code actions (`textDocument/codeAction`)
 ### Phase 5: Polish & Advanced Features (2-3 weeks)
 - [ ] Multiple server support
 - [ ] Server auto-detection
 - [ ] Configuration file support
 - [ ] Workspace symbol search
 - [ ] Rename refactoring
 ---
 ## 7. Alignment with kte Core Principles
 ### 7.1 Frontend/Backend Separation
 - LSP logic is completely separate from display
 - `DiagnosticDisplay` interface allows identical behavior across Terminal/GUI
 - Follows existing pattern: `Renderer`, `InputHandler`, `Frontend`
 ### 7.2 Testability
 - `LspClient` is abstract, enabling `MockLspClient` for testing
 - `DiagnosticDisplay` can be mocked for testing diagnostic flow
 - Change tracking can be unit tested in isolation
 ### 7.3 Performance
 - Incremental sync minimizes data sent to LSP servers
 - Async message handling doesn't block UI
 - Diagnostic rendering is batched
 ### 7.4 Simplicity
 - Minimal dependencies (nlohmann/json for JSON handling)
 - Self-contained process management
 - Clear separation of concerns
 ---
 ## 8. File Organization
 ```
 kte/
 ├── lsp/
 │   ├── LspClient.h
 │   ├── LspProcessClient.h
 │   ├── LspProcessClient.cc
 │   ├── LspManager.h
 │   ├── LspManager.cc
 │   ├── LspServerConfig.h
 │   ├── JsonRpcTransport.h
 │   ├── JsonRpcTransport.cc
 │   ├── LspTypes.h           # Position, Range, Location, etc.
 │   ├── Diagnostic.h
 │   ├── DiagnosticStore.h
 │   ├── DiagnosticStore.cc
 │   └── BufferChangeTracker.h
 ├── diagnostic/
 │   ├── DiagnosticDisplay.h
 │   ├── TerminalDiagnosticDisplay.h
 │   ├── TerminalDiagnosticDisplay.cc
 │   ├── GUIDiagnosticDisplay.h
 │   └── GUIDiagnosticDisplay.cc
 ```
 ---
 ## 9. Dependencies
 - **nlohmann/json**: JSON parsing/serialization (header-only)
 - **POSIX/Windows process APIs**: For spawning LSP servers
 - Existing kte infrastructure: `Buffer`, `Renderer`, `Frontend`, etc.
 ---
 This plan provides a solid foundation for LSP support while maintaining kte's clean architecture. The key insight is
 that LSP is fundamentally a backend feature that should be displayed through the existing frontend abstraction layer,
 ensuring consistent behavior across terminal and GUI modes.
--- a/docs/syntax
+++ b/docs/syntax
@@ -0,0 +1,102 @@
 ### Objective
 Introduce fast, minimal‑dependency syntax highlighting to kte, consistent with current architecture (Editor/Buffer + GUI/Terminal renderers), preserving ke UX and performance.
 ### Guiding principles
 - Keep core small and fast; no heavy deps (C++17 only). 
 - Start simple (stateless line regex), evolve incrementally (stateful, caching). 
 - Work in both Terminal (ncurses) and GUI (ImGui) with consistent token classes and theme mapping. 
 - Integrate without disrupting existing search highlight, selection, or cursor rendering.
 ### Scope of v1
 - Languages: plain text (off), C/C++ minimal set (keywords, types, strings, chars, comments, numbers, preprocessor). 
 - Stateless per‑line highlighting; handle single‑line comments and strings; defer multi‑line state to v2. 
 - Toggle: `:syntax on|off` and per‑buffer filetype selection.
 ### Architecture
 1. Core types (new):
   - `enum class TokenKind { Default, Keyword, Type, String, Char, Comment, Number, Preproc, Constant, Function, Operator, Punctuation, Identifier, Whitespace, Error };`
   - `struct HighlightSpan { int col_start; int col_end; TokenKind kind; };`  // 0‑based columns in buffer indices per rendered line
   - `struct LineHighlight { std::vector<HighlightSpan> spans; uint64_t version; };`
 2. Interfaces (new):
   - `class LanguageHighlighter { public: virtual ~LanguageHighlighter() = default; virtual void HighlightLine(const Buffer& buf, int row, std::vector<HighlightSpan>& out) const = 0; virtual bool Stateful() const { return false; } };`
   - `class HighlighterEngine { public: void SetHighlighter(std::unique_ptr<LanguageHighlighter>); const LineHighlight& GetLine(const Buffer&, int row, uint64_t buf_version); void InvalidateFrom(int row); };`
   - `class HighlighterRegistry { public: static const LanguageHighlighter& ForFiletype(std::string_view ft); static std::string DetectForPath(std::string_view path, std::string_view first_line); };`
 3. Editor/Buffer integration:
   - Per‑Buffer settings: `bool syntax_enabled; std::string filetype; std::unique_ptr<HighlighterEngine> highlighter;`
   - Buffer emits a monotonically increasing `version` on edit; renderers request line highlights by `(row, version)`. 
   - Invalidate cache minimally on edits (v1: current line only; v2: from current line down when stateful constructs present).
 ### Rendering integration
 - TerminalRenderer/GUIRenderer changes:
  - During line rendering, query `Editor.CurrentBuffer()->highlighter->GetLine(buf, row, buf_version)` to obtain spans.
  - Apply token styles while drawing glyph runs. 
 - Z‑order and blending:
  1) Backgrounds (e.g., selection, search highlight rectangles) 
  2) Text with syntax colors 
  3) Cursor/IME decorations
 - Search highlights must remain visible over syntax colors:
  - Terminal: combine color/attr with reverse/bold for search; if color conflicts, prefer search. 
  - GUI: draw semi‑transparent rects behind text (already present); keep syntax color for text.
 ### Theme and color mapping
 - Extend `GUITheme.h` with a `SyntaxPalette` mapping `TokenKind -> ImVec4 ink` (and optional background tint for comments/strings disabled by default). Provide default Light/Dark palettes. 
 - Terminal: map `TokenKind` to ncurses color pairs where available; degrade gracefully on 8/16‑color terminals (e.g., comments=dim, keywords=bold, strings=yellow/green if available). 
 ### Language detection
 - v1: by file extension; allow manual `:set filetype=<lang>`. 
 - v2: add shebang detection for scripts, simple modelines (optional).
 ### Commands/UX
 - `:syntax on|off` — global default; buffer inherits on open. 
 - `:set filetype=<lang>` — per‑buffer override. 
 - `:syntax reload` — rebuild patterns/themes. 
 - Status line shows filetype and syntax state when changed.
 ### Implementation plan (phased)
 1. Phase 1 — Minimal regex highlighter for C/C++
   - Implement `CppRegexHighlighter : LanguageHighlighter` with precompiled `std::regex` (or hand‑rolled simple scanners to avoid regex backtracking). Classes: line comment `//…`, block comment start `/*` (no state), string `"…"`, char `'…'` (no multiline), numbers, keywords/types, preprocessor `^\s*#\w+`. 
   - Add `HighlighterEngine` with a simple per‑row cache keyed by `(row, buf_version)`; no background worker. 
   - Integrate into both renderers; add palette to `GUITheme.h`; add terminal color selection. 
   - Add commands. 
 2. Phase 2 — Stateful constructs and more languages
   - Add state machine for multiline comments `/*…*/` and multiline strings (C++11 raw strings), with invalidation from edit line downward until state stabilizes. 
   - Add simple highlighters: JSON (strings, numbers, booleans, null, punctuation), Markdown (headers/emphasis/code fences), Shell (comments, strings, keywords), Go (types, constants, keywords), Python (strings, comments, keywords), Rust (strings, comments, keywords), Lisp (comments, strings, keywords),. 
   - Filetype detection by extension + shebang. 
 3. Phase 3 — Performance and caching
   - Viewport‑first highlighting: compute only visible rows each frame; background task warms cache around viewport. 
   - Reuse span buffers, avoid allocations; small‑vector optimization if needed. 
   - Bench with large files; ensure O(n_visible) cost per frame.
 4. Phase 4 — Extensibility
   - Public registration API for external highlighters. 
   - Optional Tree‑sitter adapter behind a compile flag (off by default) to keep dependencies minimal. 
 ### Data flow (per frame)
 - Renderer asks Editor for Buffer and viewport rows. 
 - For each row: `engine.GetLine(buf, row, buf.version)` → spans. 
 - Renderer emits runs with style from `SyntaxPalette[kind]`. 
 - Search highlights are applied as separate background rectangles (GUI) or attribute toggles (Terminal), not overriding text color.
 ### Testing
 - Unit tests for tokenization per language: golden inputs → spans. 
 - Fuzz/edge cases: escaped quotes, numeric literals, preprocessor lines. 
 - Renderer tests with `TestRenderer` asserting the sequence of style changes for a line. 
 - Performance tests: highlight 1k visible lines repeatedly; assert time under threshold.
 ### Risks and mitigations
 - Regex backtracking/perf: prefer linear scans; precompute keyword tables; avoid nested regex. 
 - Terminal color limitations: feature‑detect colors; provide bold/dim fallbacks. 
 - Stateful correctness: invalidate conservatively (from edit line downward) and cap work per frame.
 ### Deliverables
 - New files: `Highlight.h/.cc`, `HighlighterEngine.h/.cc`, `LanguageHighlighter.h`, `CppHighlighter.h/.cc`, optional `HighlighterRegistry.h/.cc`. 
 - Renderer updates: `GUIRenderer.cc`, `TerminalRenderer.cc` to consume spans. 
 - Theming: `GUITheme.h` additions for syntax colors. 
 - Editor/Buffer: per‑buffer syntax settings and highlighter handle. 
 - Commands in `Command.cc` and help text updates. 
 - Docs: README/ROADMAP update and a brief `docs/syntax.md`. 
 - Tests: unit and renderer golden tests.
--- a/docs/syntax.md
+++ b/docs/syntax.md
@@ -0,0 +1,70 @@
 Syntax highlighting in kte
 ==========================
 Overview
 --------
 kte provides lightweight syntax highlighting with a pluggable highlighter interface. The initial implementation targets C/C++ and focuses on speed and responsiveness.
 Core types
 ----------
 - `TokenKind` — token categories (keywords, types, strings, comments, numbers, preprocessor, operators, punctuation, identifiers, whitespace, etc.).
 - `HighlightSpan` — a half-open column range `[col_start, col_end)` with a `TokenKind`.
 - `LineHighlight` — a vector of `HighlightSpan` and the buffer `version` used to compute it.
 Engine and caching
 ------------------
 - `HighlighterEngine` maintains a per-line cache of `LineHighlight` keyed by row and buffer version.
 - Cache invalidation occurs when the buffer version changes or when the buffer calls `InvalidateFrom(row)`, which clears cached lines and line states from `row` downward.
 - The engine supports both stateless and stateful highlighters. For stateful highlighters, it memoizes a simple per-line state and computes lines sequentially when necessary.
 Stateful highlighters
 ---------------------
 - `LanguageHighlighter` is the base interface for stateless per-line tokenization.
 - `StatefulHighlighter` extends it with a `LineState` and the method `HighlightLineStateful(buf, row, prev_state, out)`.
 - The engine detects `StatefulHighlighter` via dynamic_cast and feeds each line the previous line’s state, caching the resulting state per line.
 C/C++ highlighter
 -----------------
 - `CppHighlighter` implements `StatefulHighlighter`.
 - Stateless constructs: line comments `//`, strings `"..."`, chars `'...'`, numbers, identifiers (keywords/types), preprocessor at beginning of line after leading whitespace, operators/punctuation, and whitespace.
 - Stateful constructs (v2):
  - Multi-line block comments `/* ... */` — the state records whether the next line continues a comment.
  - Raw strings `R"delim(... )delim"` — the state tracks whether we are inside a raw string and its delimiter `delim` until the closing sequence appears.
 Limitations and TODOs
 ---------------------
 - Raw string detection is intentionally simple and does not handle all corner cases of the C++ standard.
 - Preprocessor handling is line-based; continuation lines with `\\` are not yet tracked.
 - No semantic analysis; identifiers are classified via small keyword/type sets.
 - Additional languages (JSON, Markdown, Shell, Python, Go, Rust, Lisp, …) are planned.
 - Terminal color mapping is conservative to support 8/16-color terminals. Rich color-pair themes can be added later.
 Renderer integration
 --------------------
 - Terminal and GUI renderers request line spans via `Highlighter()->GetLine(buf, row, buf.Version())`.
 - Search highlight and cursor overlays take precedence over syntax colors.
 Extensibility (Phase 4)
 -----------------------
 - Public registration API: external code can register custom highlighters by filetype.
  - Use `HighlighterRegistry::Register("mylang", []{ return std::make_unique<MyHighlighter>(); });`
  - Registered factories are preferred over built-ins for the same filetype key.
  - Filetype keys are normalized via `HighlighterRegistry::Normalize()`.
 - Optional Tree-sitter adapter: disabled by default to keep dependencies minimal.
  - Enable with CMake option `-DKTE_ENABLE_TREESITTER=ON` and provide
    `-DTREESITTER_INCLUDE_DIR=...` and `-DTREESITTER_LIBRARY=...` if needed.
  - Register a Tree-sitter-backed highlighter for a language (example assumes you link a grammar):
    ```c++
    extern "C" const TSLanguage* tree_sitter_c();
    kte::HighlighterRegistry::RegisterTreeSitter("c", &tree_sitter_c);
    ```
  - Current adapter is a stub scaffold; it compiles and integrates cleanly when enabled, but
    intentionally emits no spans until Tree-sitter node-to-token mapping is implemented.
--- a/8
+++ b/8
@@ -1,3 +1,9 @@
 #!/usr/bin/env bash
-ls -1 *.cc *.h | grep -v '^Font.h$' | xargs cloc -fmt 3
+fmt_arg=""
 if [ "${V}" = "1" ]
 then
 	fmt_args="-fmt 3"
 fi
 ls -1 *.cc *.h | grep -v '^Font.h$' | xargs cloc ${fmt_args}
--- a/syntax/CppHighlighter.cc
+++ b/syntax/CppHighlighter.cc
@@ -0,0 +1,279 @@
 #include "CppHighlighter.h"
 #include "../Buffer.h"
 #include <cctype>
 namespace kte {
 static bool
 is_digit(char c)
 {
 	return c >= '0' && c <= '9';
 }
 CppHighlighter::CppHighlighter()
 {
 	const char *kw[] = {
 		"if", "else", "for", "while", "do", "switch", "case", "default", "break", "continue",
 		"return", "goto", "struct", "class", "namespace", "using", "template", "typename",
 		"public", "private", "protected", "virtual", "override", "const", "constexpr", "auto",
 		"static", "inline", "operator", "new", "delete", "try", "catch", "throw", "friend",
 		"enum", "union", "extern", "volatile", "mutable", "noexcept", "sizeof", "this"
 	};
 	for (auto s: kw)
 		keywords_.insert(s);
 	const char *types[] = {
 		"int", "long", "short", "char", "signed", "unsigned", "float", "double", "void",
 		"bool", "wchar_t", "size_t", "ptrdiff_t", "uint8_t", "uint16_t", "uint32_t", "uint64_t",
 		"int8_t", "int16_t", "int32_t", "int64_t"
 	};
 	for (auto s: types)
 		types_.insert(s);
 }
 bool
 CppHighlighter::is_ident_start(char c)
 {
 	return std::isalpha(static_cast<unsigned char>(c)) || c == '_';
 }
 bool
 CppHighlighter::is_ident_char(char c)
 {
 	return std::isalnum(static_cast<unsigned char>(c)) || c == '_';
 }
 void
 CppHighlighter::HighlightLine(const Buffer &buf, int row, std::vector<HighlightSpan> &out) const
 {
 	// Stateless entry simply delegates to stateful with a clean previous state
 	StatefulHighlighter::LineState prev;
 	(void) HighlightLineStateful(buf, row, prev, out);
 }
 StatefulHighlighter::LineState
 CppHighlighter::HighlightLineStateful(const Buffer &buf,
                                      int row,
                                      const LineState &prev,
                                      std::vector<HighlightSpan> &out) const
 {
 	const auto &rows                     = buf.Rows();
 	StatefulHighlighter::LineState state = prev;
 	if (row < 0 || static_cast<std::size_t>(row) >= rows.size())
 		return state;
 	std::string s = static_cast<std::string>(rows[static_cast<std::size_t>(row)]);
 	if (s.empty())
 		return state;
 	auto push = [&](int a, int b, TokenKind k) {
 		if (b > a)
 			out.push_back({a, b, k});
 	};
 	int n   = static_cast<int>(s.size());
 	int bol = 0;
 	while (bol < n && (s[bol] == ' ' || s[bol] == '\t'))
 		++bol;
 	int i = 0;
 	// Continue multi-line raw string from previous line
 	if (state.in_raw_string) {
 		std::string needle = ")" + state.raw_delim + "\"";
 		auto pos           = s.find(needle);
 		if (pos == std::string::npos) {
 			push(0, n, TokenKind::String);
 			state.in_raw_string = true;
 			return state;
 		} else {
 			int end = static_cast<int>(pos + needle.size());
 			push(0, end, TokenKind::String);
 			i                   = end;
 			state.in_raw_string = false;
 			state.raw_delim.clear();
 		}
 	}
 	// Continue multi-line block comment from previous line
 	if (state.in_block_comment) {
 		int j = i;
 		while (i + 1 < n) {
 			if (s[i] == '*' && s[i + 1] == '/') {
 				i += 2;
 				push(j, i, TokenKind::Comment);
 				state.in_block_comment = false;
 				break;
 			}
 			++i;
 		}
 		if (state.in_block_comment) {
 			push(j, n, TokenKind::Comment);
 			return state;
 		}
 	}
 	while (i < n) {
 		char c = s[i];
 		// Preprocessor at beginning of line (after leading whitespace)
 		if (i == bol && c == '#') {
 			push(0, n, TokenKind::Preproc);
 			break;
 		}
 		// Whitespace
 		if (c == ' ' || c == '\t') {
 			int j = i + 1;
 			while (j < n && (s[j] == ' ' || s[j] == '\t'))
 				++j;
 			push(i, j, TokenKind::Whitespace);
 			i = j;
 			continue;
 		}
 		// Line comment
 		if (c == '/' && i + 1 < n && s[i + 1] == '/') {
 			push(i, n, TokenKind::Comment);
 			break;
 		}
 		// Block comment
 		if (c == '/' && i + 1 < n && s[i + 1] == '*') {
 			int j       = i + 2;
 			bool closed = false;
 			while (j + 1 <= n) {
 				if (j + 1 < n && s[j] == '*' && s[j + 1] == '/') {
 					j += 2;
 					closed = true;
 					break;
 				}
 				++j;
 			}
 			if (closed) {
 				push(i, j, TokenKind::Comment);
 				i = j;
 				continue;
 			}
 			// Spill to next lines
 			push(i, n, TokenKind::Comment);
 			state.in_block_comment = true;
 			return state;
 		}
 		// Raw string start: very simple detection: R"delim(
 		if (c == 'R' && i + 1 < n && s[i + 1] == '"') {
 			int k = i + 2;
 			std::string delim;
 			while (k < n && s[k] != '(') {
 				delim.push_back(s[k]);
 				++k;
 			}
 			if (k < n && s[k] == '(') {
 				int body_start     = k + 1;
 				std::string needle = ")" + delim + "\"";
 				auto pos           = s.find(needle, static_cast<std::size_t>(body_start));
 				if (pos == std::string::npos) {
 					push(i, n, TokenKind::String);
 					state.in_raw_string = true;
 					state.raw_delim     = delim;
 					return state;
 				} else {
 					int end = static_cast<int>(pos + needle.size());
 					push(i, end, TokenKind::String);
 					i = end;
 					continue;
 				}
 			}
 			// If malformed, just treat 'R' as identifier fallback
 		}
 		// Regular string literal
 		if (c == '"') {
 			int j    = i + 1;
 			bool esc = false;
 			while (j < n) {
 				char d = s[j++];
 				if (esc) {
 					esc = false;
 					continue;
 				}
 				if (d == '\\') {
 					esc = true;
 					continue;
 				}
 				if (d == '"')
 					break;
 			}
 			push(i, j, TokenKind::String);
 			i = j;
 			continue;
 		}
 		// Char literal
 		if (c == '\'') {
 			int j    = i + 1;
 			bool esc = false;
 			while (j < n) {
 				char d = s[j++];
 				if (esc) {
 					esc = false;
 					continue;
 				}
 				if (d == '\\') {
 					esc = true;
 					continue;
 				}
 				if (d == '\'')
 					break;
 			}
 			push(i, j, TokenKind::Char);
 			i = j;
 			continue;
 		}
 		// Number literal (simple)
 		if (is_digit(c) || (c == '.' && i + 1 < n && is_digit(s[i + 1]))) {
 			int j = i + 1;
 			while (j < n && (std::isalnum(static_cast<unsigned char>(s[j])) || s[j] == '.' || s[j] == 'x' ||
 			                 s[j] == 'X' || s[j] == 'b' || s[j] == 'B' || s[j] == '_'))
 				++j;
 			push(i, j, TokenKind::Number);
 			i = j;
 			continue;
 		}
 		// Identifier / keyword / type
 		if (is_ident_start(c)) {
 			int j = i + 1;
 			while (j < n && is_ident_char(s[j]))
 				++j;
 			std::string id = s.substr(i, j - i);
 			TokenKind k    = TokenKind::Identifier;
 			if (keywords_.count(id))
 				k = TokenKind::Keyword;
 			else if (types_.count(id))
 				k = TokenKind::Type;
 			push(i, j, k);
 			i = j;
 			continue;
 		}
 		// Operators and punctuation (single char for now)
 		TokenKind kind = TokenKind::Operator;
 		if (std::ispunct(static_cast<unsigned char>(c)) && c != '_' && c != '#') {
 			if (c == ';' || c == ',' || c == '(' || c == ')' || c == '{' || c == '}' || c == '[' || c ==
 			    ']')
 				kind = TokenKind::Punctuation;
 			push(i, i + 1, kind);
 			++i;
 			continue;
 		}
 		// Fallback
 		push(i, i + 1, TokenKind::Default);
 		++i;
 	}
 	return state;
 }
 } // namespace kte
--- a/syntax/CppHighlighter.h
+++ b/syntax/CppHighlighter.h
@@ -0,0 +1,35 @@
 // CppHighlighter.h - minimal stateless C/C++ line highlighter
 #pragma once
 #include <regex>
 #include <string>
 #include <unordered_set>
 #include <vector>
 #include "LanguageHighlighter.h"
 class Buffer;
 namespace kte {
 class CppHighlighter final : public StatefulHighlighter {
 public:
 	CppHighlighter();
 	~CppHighlighter() override = default;
 	void HighlightLine(const Buffer &buf, int row, std::vector<HighlightSpan> &out) const override;
 	LineState HighlightLineStateful(const Buffer &buf,
 	                                int row,
 	                                const LineState &prev,
 	                                std::vector<HighlightSpan> &out) const override;
 private:
 	std::unordered_set<std::string> keywords_;
 	std::unordered_set<std::string> types_;
 	static bool is_ident_start(char c);
 	static bool is_ident_char(char c);
 };
 } // namespace kte
--- a/syntax/ErlangHighlighter.cc
+++ b/syntax/ErlangHighlighter.cc
@@ -0,0 +1,159 @@
 #include "ErlangHighlighter.h"
 #include "../Buffer.h"
 #include <cctype>
 namespace kte {
 static void
 push(std::vector<HighlightSpan> &out, int a, int b, TokenKind k)
 {
 	if (b > a)
 		out.push_back({a, b, k});
 }
 static bool
 is_ident_start(char c)
 {
 	return std::isalpha(static_cast<unsigned char>(c)) || c == '_' || c == '\'';
 }
 static bool
 is_ident_char(char c)
 {
 	return std::isalnum(static_cast<unsigned char>(c)) || c == '_' || c == '@' || c == ':' || c == '?';
 }
 ErlangHighlighter::ErlangHighlighter()
 {
 	const char *kw[] = {
 		"after", "begin", "case", "catch", "cond", "div", "end", "fun", "if", "let", "of",
 		"receive", "when", "try", "rem", "and", "andalso", "orelse", "not", "band", "bor", "bxor",
 		"bnot", "xor", "module", "export", "import", "record", "define", "undef", "include", "include_lib"
 	};
 	for (auto s: kw)
 		kws_.insert(s);
 }
 void
 ErlangHighlighter::HighlightLine(const Buffer &buf, int row, std::vector<HighlightSpan> &out) const
 {
 	const auto &rows = buf.Rows();
 	if (row < 0 || static_cast<std::size_t>(row) >= rows.size())
 		return;
 	std::string s = static_cast<std::string>(rows[static_cast<std::size_t>(row)]);
 	int n         = static_cast<int>(s.size());
 	int i         = 0;
 	while (i < n) {
 		char c = s[i];
 		if (c == ' ' || c == '\t') {
 			int j = i + 1;
 			while (j < n && (s[j] == ' ' || s[j] == '\t'))
 				++j;
 			push(out, i, j, TokenKind::Whitespace);
 			i = j;
 			continue;
 		}
 		// comment
 		if (c == '%') {
 			push(out, i, n, TokenKind::Comment);
 			break;
 		}
 		// strings
 		if (c == '"') {
 			int j    = i + 1;
 			bool esc = false;
 			while (j < n) {
 				char d = s[j++];
 				if (esc) {
 					esc = false;
 					continue;
 				}
 				if (d == '\\') {
 					esc = true;
 					continue;
 				}
 				if (d == '"')
 					break;
 			}
 			push(out, i, j, TokenKind::String);
 			i = j;
 			continue;
 		}
 		// char literal $X
 		if (c == '$') {
 			int j = i + 1;
 			if (j < n && s[j] == '\\' && j + 1 < n)
 				j += 2;
 			else if (j < n)
 				++j;
 			push(out, i, j, TokenKind::Char);
 			i = j;
 			continue;
 		}
 		// numbers
 		if (std::isdigit(static_cast<unsigned char>(c))) {
 			int j = i + 1;
 			while (j < n && (std::isalnum(static_cast<unsigned char>(s[j])) || s[j] == '#' || s[j] == '.' ||
 			                 s[j] == '_'))
 				++j;
 			push(out, i, j, TokenKind::Number);
 			i = j;
 			continue;
 		}
 		// atoms/variables/identifiers (including quoted atoms)
 		if (is_ident_start(c)) {
 			// quoted atom: '...'
 			if (c == '\'') {
 				int j    = i + 1;
 				bool esc = false;
 				while (j < n) {
 					char d = s[j++];
 					if (d == '\'') {
 						if (j < n && s[j] == '\'') {
 							++j;
 							continue;
 						}
 						break;
 					}
 					if (d == '\\')
 						esc = !esc;
 				}
 				push(out, i, j, TokenKind::Identifier);
 				i = j;
 				continue;
 			}
 			int j = i + 1;
 			while (j < n && is_ident_char(s[j]))
 				++j;
 			std::string id = s.substr(i, j - i);
 			// lowercase leading -> atom/function/module; uppercase or '_' -> variable
 			TokenKind k = TokenKind::Identifier;
 			// keyword check (lowercase)
 			std::string lower;
 			lower.reserve(id.size());
 			for (char ch: id)
 				lower.push_back(static_cast<char>(std::tolower(static_cast<unsigned char>(ch))));
 			if (kws_.count(lower))
 				k = TokenKind::Keyword;
 			push(out, i, j, k);
 			i = j;
 			continue;
 		}
 		if (std::ispunct(static_cast<unsigned char>(c))) {
 			TokenKind k = TokenKind::Operator;
 			if (c == ',' || c == ';' || c == '(' || c == ')' || c == '[' || c == ']' || c == '{' || c ==
 			    '}')
 				k = TokenKind::Punctuation;
 			push(out, i, i + 1, k);
 			++i;
 			continue;
 		}
 		push(out, i, i + 1, TokenKind::Default);
 		++i;
 	}
 }
 } // namespace kte
--- a/syntax/ErlangHighlighter.h
+++ b/syntax/ErlangHighlighter.h
@@ -0,0 +1,17 @@
 // ErlangHighlighter.h - simple Erlang highlighter
 #pragma once
 #include "LanguageHighlighter.h"
 #include <unordered_set>
 namespace kte {
 class ErlangHighlighter final : public LanguageHighlighter {
 public:
 	ErlangHighlighter();
 	void HighlightLine(const Buffer &buf, int row, std::vector<HighlightSpan> &out) const override;
 private:
 	std::unordered_set<std::string> kws_;
 };
 } // namespace kte
--- a/syntax/ForthHighlighter.cc
+++ b/syntax/ForthHighlighter.cc
@@ -0,0 +1,121 @@
 #include "ForthHighlighter.h"
 #include "../Buffer.h"
 #include <cctype>
 namespace kte {
 static void
 push(std::vector<HighlightSpan> &out, int a, int b, TokenKind k)
 {
 	if (b > a)
 		out.push_back({a, b, k});
 }
 static bool
 is_word_char(char c)
 {
 	return std::isalnum(static_cast<unsigned char>(c)) || c == '_' || c == '>' || c == '<' || c == '?';
 }
 ForthHighlighter::ForthHighlighter()
 {
 	const char *kw[] = {
 		":", ";", "if", "else", "then", "begin", "until", "while", "repeat",
 		"do", "loop", "+loop", "leave", "again", "case", "of", "endof", "endcase",
 		".", ".r", ".s", ".\"", ",", "cr", "emit", "type", "key",
 		"+", "-", "*", "/", "mod", "/mod", "+-", "abs", "min", "max",
 		"dup", "drop", "swap", "over", "rot", "-rot", "nip", "tuck", "pick", "roll",
 		"and", "or", "xor", "invert", "lshift", "rshift",
 		"variable", "constant", "value", "to", "create", "does>", "allot", ",",
 		"cells", "cell+", "chars", "char+",
 		"[", "]", "immediate",
 		"s\"", ".\""
 	};
 	for (auto s: kw)
 		kws_.insert(s);
 }
 void
 ForthHighlighter::HighlightLine(const Buffer &buf, int row, std::vector<HighlightSpan> &out) const
 {
 	const auto &rows = buf.Rows();
 	if (row < 0 || static_cast<std::size_t>(row) >= rows.size())
 		return;
 	std::string s = static_cast<std::string>(rows[static_cast<std::size_t>(row)]);
 	int n         = static_cast<int>(s.size());
 	int i         = 0;
 	while (i < n) {
 		char c = s[i];
 		if (c == ' ' || c == '\t') {
 			int j = i + 1;
 			while (j < n && (s[j] == ' ' || s[j] == '\t'))
 				++j;
 			push(out, i, j, TokenKind::Whitespace);
 			i = j;
 			continue;
 		}
 		// backslash comment to end of line
 		if (c == '\\') {
 			push(out, i, n, TokenKind::Comment);
 			break;
 		}
 		// parenthesis comment ( ... ) if at word boundary
 		if (c == '(') {
 			int j = i + 1;
 			while (j < n && s[j] != ')')
 				++j;
 			if (j < n)
 				++j;
 			push(out, i, j, TokenKind::Comment);
 			i = j;
 			continue;
 		}
 		// strings: ." ... " and S" ... " and raw "..."
 		if (c == '"') {
 			int j = i + 1;
 			while (j < n && s[j] != '"')
 				++j;
 			if (j < n)
 				++j;
 			push(out, i, j, TokenKind::String);
 			i = j;
 			continue;
 		}
 		if (std::isdigit(static_cast<unsigned char>(c))) {
 			int j = i + 1;
 			while (j < n && (std::isalnum(static_cast<unsigned char>(s[j])) || s[j] == '.' || s[j] == '#'))
 				++j;
 			push(out, i, j, TokenKind::Number);
 			i = j;
 			continue;
 		}
 		// word/identifier
 		if (std::isalpha(static_cast<unsigned char>(c)) || std::ispunct(static_cast<unsigned char>(c))) {
 			int j = i + 1;
 			while (j < n && is_word_char(s[j]))
 				++j;
 			std::string w = s.substr(i, j - i);
 			// normalize to lowercase for keyword compare (Forth is case-insensitive typically)
 			std::string lower;
 			lower.reserve(w.size());
 			for (char ch: w)
 				lower.push_back(static_cast<char>(std::tolower(static_cast<unsigned char>(ch))));
 			TokenKind k = kws_.count(lower) ? TokenKind::Keyword : TokenKind::Identifier;
 			// Single-char punctuation fallback
 			if (w.size() == 1 && std::ispunct(static_cast<unsigned char>(w[0])) && !kws_.count(lower)) {
 				k = (w[0] == '(' || w[0] == ')' || w[0] == ',')
 					    ? TokenKind::Punctuation
 					    : TokenKind::Operator;
 			}
 			push(out, i, j, k);
 			i = j;
 			continue;
 		}
 		push(out, i, i + 1, TokenKind::Default);
 		++i;
 	}
 }
 } // namespace kte
--- a/syntax/ForthHighlighter.h
+++ b/syntax/ForthHighlighter.h
@@ -0,0 +1,17 @@
 // ForthHighlighter.h - simple Forth highlighter
 #pragma once
 #include "LanguageHighlighter.h"
 #include <unordered_set>
 namespace kte {
 class ForthHighlighter final : public LanguageHighlighter {
 public:
 	ForthHighlighter();
 	void HighlightLine(const Buffer &buf, int row, std::vector<HighlightSpan> &out) const override;
 private:
 	std::unordered_set<std::string> kws_;
 };
 } // namespace kte
--- a/syntax/GoHighlighter.cc
+++ b/syntax/GoHighlighter.cc
@@ -0,0 +1,157 @@
 #include "GoHighlighter.h"
 #include "../Buffer.h"
 #include <cctype>
 namespace kte {
 static void
 push(std::vector<HighlightSpan> &out, int a, int b, TokenKind k)
 {
 	if (b > a)
 		out.push_back({a, b, k});
 }
 static bool
 is_ident_start(char c)
 {
 	return std::isalpha(static_cast<unsigned char>(c)) || c == '_';
 }
 static bool
 is_ident_char(char c)
 {
 	return std::isalnum(static_cast<unsigned char>(c)) || c == '_';
 }
 GoHighlighter::GoHighlighter()
 {
 	const char *kw[] = {
 		"break", "case", "chan", "const", "continue", "default", "defer", "else", "fallthrough", "for", "func",
 		"go", "goto", "if", "import", "interface", "map", "package", "range", "return", "select", "struct",
 		"switch", "type", "var"
 	};
 	for (auto s: kw)
 		kws_.insert(s);
 	const char *tp[] = {
 		"bool", "byte", "complex64", "complex128", "error", "float32", "float64", "int", "int8", "int16",
 		"int32", "int64", "rune", "string", "uint", "uint8", "uint16", "uint32", "uint64", "uintptr"
 	};
 	for (auto s: tp)
 		types_.insert(s);
 }
 void
 GoHighlighter::HighlightLine(const Buffer &buf, int row, std::vector<HighlightSpan> &out) const
 {
 	const auto &rows = buf.Rows();
 	if (row < 0 || static_cast<std::size_t>(row) >= rows.size())
 		return;
 	std::string s = static_cast<std::string>(rows[static_cast<std::size_t>(row)]);
 	int n         = static_cast<int>(s.size());
 	int i         = 0;
 	int bol       = 0;
 	while (bol < n && (s[bol] == ' ' || s[bol] == '\t'))
 		++bol;
 	// line comment
 	while (i < n) {
 		char c = s[i];
 		if (c == ' ' || c == '\t') {
 			int j = i + 1;
 			while (j < n && (s[j] == ' ' || s[j] == '\t'))
 				++j;
 			push(out, i, j, TokenKind::Whitespace);
 			i = j;
 			continue;
 		}
 		if (c == '/' && i + 1 < n && s[i + 1] == '/') {
 			push(out, i, n, TokenKind::Comment);
 			break;
 		}
 		if (c == '/' && i + 1 < n && s[i + 1] == '*') {
 			int j       = i + 2;
 			bool closed = false;
 			while (j + 1 <= n) {
 				if (j + 1 < n && s[j] == '*' && s[j + 1] == '/') {
 					j += 2;
 					closed = true;
 					break;
 				}
 				++j;
 			}
 			if (!closed) {
 				push(out, i, n, TokenKind::Comment);
 				break;
 			} else {
 				push(out, i, j, TokenKind::Comment);
 				i = j;
 				continue;
 			}
 		}
 		if (c == '"' || c == '`') {
 			char q   = c;
 			int j    = i + 1;
 			bool esc = false;
 			if (q == '`') {
 				while (j < n && s[j] != '`')
 					++j;
 				if (j < n)
 					++j;
 			} else {
 				while (j < n) {
 					char d = s[j++];
 					if (esc) {
 						esc = false;
 						continue;
 					}
 					if (d == '\\') {
 						esc = true;
 						continue;
 					}
 					if (d == '"')
 						break;
 				}
 			}
 			push(out, i, j, TokenKind::String);
 			i = j;
 			continue;
 		}
 		if (std::isdigit(static_cast<unsigned char>(c))) {
 			int j = i + 1;
 			while (j < n && (std::isalnum(static_cast<unsigned char>(s[j])) || s[j] == '.' || s[j] == 'x' ||
 			                 s[j] == 'X' || s[j] == '_'))
 				++j;
 			push(out, i, j, TokenKind::Number);
 			i = j;
 			continue;
 		}
 		if (is_ident_start(c)) {
 			int j = i + 1;
 			while (j < n && is_ident_char(s[j]))
 				++j;
 			std::string id = s.substr(i, j - i);
 			TokenKind k    = TokenKind::Identifier;
 			if (kws_.count(id))
 				k = TokenKind::Keyword;
 			else if (types_.count(id))
 				k = TokenKind::Type;
 			push(out, i, j, k);
 			i = j;
 			continue;
 		}
 		if (std::ispunct(static_cast<unsigned char>(c))) {
 			TokenKind k = TokenKind::Operator;
 			if (c == ';' || c == ',' || c == '(' || c == ')' || c == '{' || c == '}' || c == '[' || c ==
 			    ']')
 				k = TokenKind::Punctuation;
 			push(out, i, i + 1, k);
 			++i;
 			continue;
 		}
 		push(out, i, i + 1, TokenKind::Default);
 		++i;
 	}
 }
 } // namespace kte
--- a/syntax/GoHighlighter.h
+++ b/syntax/GoHighlighter.h
@@ -0,0 +1,18 @@
 // GoHighlighter.h - simple Go highlighter
 #pragma once
 #include "LanguageHighlighter.h"
 #include <unordered_set>
 namespace kte {
 class GoHighlighter final : public LanguageHighlighter {
 public:
 	GoHighlighter();
 	void HighlightLine(const Buffer &buf, int row, std::vector<HighlightSpan> &out) const override;
 private:
 	std::unordered_set<std::string> kws_;
 	std::unordered_set<std::string> types_;
 };
 } // namespace kte
--- a/syntax/HighlighterEngine.cc
+++ b/syntax/HighlighterEngine.cc
@@ -0,0 +1,209 @@
 #include "HighlighterEngine.h"
 #include "../Buffer.h"
 #include "LanguageHighlighter.h"
 #include <thread>
 namespace kte {
 HighlighterEngine::HighlighterEngine() = default;
 HighlighterEngine::~HighlighterEngine()
 {
 	// stop background worker
 	if (worker_running_.load()) {
 		{
 			std::lock_guard<std::mutex> lock(mtx_);
 			worker_running_.store(false);
 			has_request_ = true; // wake it up to exit
 		}
 		cv_.notify_one();
 		if (worker_.joinable())
 			worker_.join();
 	}
 }
 void
 HighlighterEngine::SetHighlighter(std::unique_ptr<LanguageHighlighter> hl)
 {
 	std::lock_guard<std::mutex> lock(mtx_);
 	hl_ = std::move(hl);
 	cache_.clear();
 	state_cache_.clear();
 	state_last_contig_.clear();
 }
 const LineHighlight &
 HighlighterEngine::GetLine(const Buffer &buf, int row, std::uint64_t buf_version) const
 {
 	std::unique_lock<std::mutex> lock(mtx_);
 	auto it = cache_.find(row);
 	if (it != cache_.end() && it->second.version == buf_version) {
 		return it->second;
 	}
 	// Prepare destination slot to reuse its capacity and avoid allocations
 	LineHighlight &slot = cache_[row];
 	slot.version        = buf_version;
 	slot.spans.clear();
 	if (!hl_) {
 		return slot;
 	}
 	// Copy shared_ptr-like raw pointer for use outside critical sections
 	LanguageHighlighter *hl_ptr = hl_.get();
 	bool is_stateful            = dynamic_cast<StatefulHighlighter *>(hl_ptr) != nullptr;
 	if (!is_stateful) {
 		// Stateless fast path: we can release the lock while computing to reduce contention
 		auto &out = slot.spans;
 		lock.unlock();
 		hl_ptr->HighlightLine(buf, row, out);
 		return cache_.at(row);
 	}
 	// Stateful path: we need to walk from a known previous state. Keep lock while consulting caches,
 	// but release during heavy computation.
 	auto *stateful = static_cast<StatefulHighlighter *>(hl_ptr);
 	StatefulHighlighter::LineState prev_state;
 	int start_row = -1;
 	if (!state_cache_.empty()) {
 		// linear search over map (unordered), track best candidate
 		int best = -1;
 		for (const auto &kv: state_cache_) {
 			int r = kv.first;
 			if (r <= row - 1 && kv.second.version == buf_version) {
 				if (r > best)
 					best = r;
 			}
 		}
 		if (best >= 0) {
 			start_row  = best;
 			prev_state = state_cache_.at(best).state;
 		}
 	}
 	// We'll compute states and the target line's spans without holding the lock for most of the work.
 	// Create a local copy of prev_state and iterate rows; we will update caches under lock.
 	lock.unlock();
 	StatefulHighlighter::LineState cur_state = prev_state;
 	for (int r = start_row + 1; r <= row; ++r) {
 		std::vector<HighlightSpan> tmp;
 		std::vector<HighlightSpan> &out = (r == row) ? slot.spans : tmp;
 		auto next_state                 = stateful->HighlightLineStateful(buf, r, cur_state, out);
 		// Update state cache for r
 		std::lock_guard<std::mutex> gl(mtx_);
 		StateEntry se;
 		se.version      = buf_version;
 		se.state        = next_state;
 		state_cache_[r] = se;
 		cur_state       = next_state;
 	}
 	// Return reference under lock to ensure slot's address stability in map
 	lock.lock();
 	return cache_.at(row);
 }
 void
 HighlighterEngine::InvalidateFrom(int row)
 {
 	std::lock_guard<std::mutex> lock(mtx_);
 	if (cache_.empty())
 		return;
 	// Simple implementation: erase all rows >= row
 	for (auto it = cache_.begin(); it != cache_.end();) {
 		if (it->first >= row)
 			it = cache_.erase(it);
 		else
 			++it;
 	}
 	if (!state_cache_.empty()) {
 		for (auto it = state_cache_.begin(); it != state_cache_.end();) {
 			if (it->first >= row)
 				it = state_cache_.erase(it);
 			else
 				++it;
 		}
 	}
 }
 void
 HighlighterEngine::ensure_worker_started() const
 {
 	if (worker_running_.load())
 		return;
 	worker_running_.store(true);
 	worker_ = std::thread([this]() {
 		this->worker_loop();
 	});
 }
 void
 HighlighterEngine::worker_loop() const
 {
 	std::unique_lock<std::mutex> lock(mtx_);
 	while (worker_running_.load()) {
 		cv_.wait(lock, [this]() {
 			return has_request_ || !worker_running_.load();
 		});
 		if (!worker_running_.load())
 			break;
 		WarmRequest req = pending_;
 		has_request_    = false;
 		// Copy locals then release lock while computing
 		lock.unlock();
 		if (req.buf) {
 			int start = std::max(0, req.start_row);
 			int end   = std::max(start, req.end_row);
 			for (int r = start; r <= end; ++r) {
 				// Re-check version staleness quickly by peeking cache version; not strictly necessary
 				// Compute line; GetLine is thread-safe
 				(void) this->GetLine(*req.buf, r, req.version);
 			}
 		}
 		lock.lock();
 	}
 }
 void
 HighlighterEngine::PrefetchViewport(const Buffer &buf, int first_row, int row_count, std::uint64_t buf_version,
                                    int warm_margin) const
 {
 	if (row_count <= 0)
 		return;
 	// Synchronously compute visible rows to ensure cache hits during draw
 	int start    = std::max(0, first_row);
 	int end      = start + row_count - 1;
 	int max_rows = static_cast<int>(buf.Nrows());
 	if (start >= max_rows)
 		return;
 	if (end >= max_rows)
 		end = max_rows - 1;
 	for (int r = start; r <= end; ++r) {
 		(void) GetLine(buf, r, buf_version);
 	}
 	// Enqueue background warm-around
 	int warm_start = std::max(0, start - warm_margin);
 	int warm_end   = std::min(max_rows - 1, end + warm_margin);
 	{
 		std::lock_guard<std::mutex> lock(mtx_);
 		pending_.buf       = &buf;
 		pending_.version   = buf_version;
 		pending_.start_row = warm_start;
 		pending_.end_row   = warm_end;
 		has_request_       = true;
 	}
 	ensure_worker_started();
 	cv_.notify_one();
 }
 } // namespace kte
--- a/syntax/HighlighterEngine.h
+++ b/syntax/HighlighterEngine.h
@@ -0,0 +1,85 @@
 // HighlighterEngine.h - caching layer for per-line highlights
 #pragma once
 #include <cstdint>
 #include <memory>
 #include <unordered_map>
 #include <vector>
 #include <mutex>
 #include <condition_variable>
 #include <atomic>
 #include <thread>
 #include "../Highlight.h"
 #include "LanguageHighlighter.h"
 class Buffer;
 namespace kte {
 class HighlighterEngine {
 public:
 	HighlighterEngine();
 	~HighlighterEngine();
 	void SetHighlighter(std::unique_ptr<LanguageHighlighter> hl);
 	// Retrieve highlights for a given line and buffer version.
 	// If cache is stale, recompute using the current highlighter.
 	const LineHighlight &GetLine(const Buffer &buf, int row, std::uint64_t buf_version) const;
 	// Invalidate cached lines from row (inclusive)
 	void InvalidateFrom(int row);
 	bool HasHighlighter() const
 	{
 		return static_cast<bool>(hl_);
 	}
 	// Phase 3: viewport-first prefetch and background warming
 	// Compute only the visible range now, and enqueue a background warm-around task.
 	// warm_margin: how many extra lines above/below to warm in the background.
 	void PrefetchViewport(const Buffer &buf, int first_row, int row_count, std::uint64_t buf_version,
 	                      int warm_margin = 200) const;
 private:
 	std::unique_ptr<LanguageHighlighter> hl_;
 	// Simple cache by row index (mutable to allow caching in const GetLine)
 	mutable std::unordered_map<int, LineHighlight> cache_;
 	// For stateful highlighters, remember per-line state (state after finishing that row)
 	struct StateEntry {
 		std::uint64_t version{0};
 		// Using the interface type; forward-declare via header
 		StatefulHighlighter::LineState state;
 	};
 	mutable std::unordered_map<int, StateEntry> state_cache_;
 	// Track best known contiguous state row for a given version to avoid O(n) scans
 	mutable std::unordered_map<std::uint64_t, int> state_last_contig_;
 	// Thread-safety for caches and background worker state
 	mutable std::mutex mtx_;
 	// Background warmer
 	struct WarmRequest {
 		const Buffer *buf{nullptr};
 		std::uint64_t version{0};
 		int start_row{0};
 		int end_row{0}; // inclusive
 	};
 	mutable std::condition_variable cv_;
 	mutable std::thread worker_;
 	mutable std::atomic<bool> worker_running_{false};
 	mutable bool has_request_{false};
 	mutable WarmRequest pending_{};
 	void ensure_worker_started() const;
 	void worker_loop() const;
 };
 } // namespace kte
--- a/syntax/HighlighterRegistry.cc
+++ b/syntax/HighlighterRegistry.cc
@@ -0,0 +1,247 @@
 #include "HighlighterRegistry.h"
 #include "CppHighlighter.h"
 #include <algorithm>
 #include <filesystem>
 #include <vector>
 #include <cctype>
 // Forward declare simple highlighters implemented in this project
 namespace kte {
 // Registration storage
 struct RegEntry {
 	std::string ft; // normalized
 	HighlighterRegistry::Factory factory;
 };
 static std::vector<RegEntry> &
 registry()
 {
 	static std::vector<RegEntry> reg;
 	return reg;
 }
 class JSONHighlighter;
 class MarkdownHighlighter;
 class ShellHighlighter;
 class GoHighlighter;
 class PythonHighlighter;
 class RustHighlighter;
 class LispHighlighter;
 class SqlHighlighter;
 class ErlangHighlighter;
 class ForthHighlighter;
 }
 // Headers for the above
 #include "JsonHighlighter.h"
 #include "MarkdownHighlighter.h"
 #include "ShellHighlighter.h"
 #include "GoHighlighter.h"
 #include "PythonHighlighter.h"
 #include "RustHighlighter.h"
 #include "LispHighlighter.h"
 #include "SqlHighlighter.h"
 #include "ErlangHighlighter.h"
 #include "ForthHighlighter.h"
 namespace kte {
 static std::string
 to_lower(std::string_view s)
 {
 	std::string r(s);
 	std::transform(r.begin(), r.end(), r.begin(), [](unsigned char c) {
 		return static_cast<char>(std::tolower(c));
 	});
 	return r;
 }
 std::string
 HighlighterRegistry::Normalize(std::string_view ft)
 {
 	std::string f = to_lower(ft);
 	if (f == "c" || f == "c++" || f == "cc" || f == "hpp" || f == "hh" || f == "h" || f == "cxx")
 		return "cpp";
 	if (f == "cpp")
 		return "cpp";
 	if (f == "json")
 		return "json";
 	if (f == "markdown" || f == "md" || f == "mkd" || f == "mdown")
 		return "markdown";
 	if (f == "shell" || f == "sh" || f == "bash" || f == "zsh" || f == "ksh" || f == "fish")
 		return "shell";
 	if (f == "go" || f == "golang")
 		return "go";
 	if (f == "py" || f == "python")
 		return "python";
 	if (f == "rs" || f == "rust")
 		return "rust";
 	if (f == "lisp" || f == "scheme" || f == "scm" || f == "rkt" || f == "el" || f == "clj" || f == "cljc" || f ==
 	    "cl")
 		return "lisp";
 	if (f == "sql" || f == "sqlite" || f == "sqlite3")
 		return "sql";
 	if (f == "erlang" || f == "erl" || f == "hrl")
 		return "erlang";
 	if (f == "forth" || f == "fth" || f == "4th" || f == "fs")
 		return "forth";
 	return f;
 }
 std::unique_ptr<LanguageHighlighter>
 HighlighterRegistry::CreateFor(std::string_view filetype)
 {
 	std::string ft = Normalize(filetype);
 	// Prefer externally registered factories
 	for (const auto &e: registry()) {
 		if (e.ft == ft && e.factory)
 			return e.factory();
 	}
 	if (ft == "cpp")
 		return std::make_unique<CppHighlighter>();
 	if (ft == "json")
 		return std::make_unique<JSONHighlighter>();
 	if (ft == "markdown")
 		return std::make_unique<MarkdownHighlighter>();
 	if (ft == "shell")
 		return std::make_unique<ShellHighlighter>();
 	if (ft == "go")
 		return std::make_unique<GoHighlighter>();
 	if (ft == "python")
 		return std::make_unique<PythonHighlighter>();
 	if (ft == "rust")
 		return std::make_unique<RustHighlighter>();
 	if (ft == "lisp")
 		return std::make_unique<LispHighlighter>();
 	if (ft == "sql")
 		return std::make_unique<SqlHighlighter>();
 	if (ft == "erlang")
 		return std::make_unique<ErlangHighlighter>();
 	if (ft == "forth")
 		return std::make_unique<ForthHighlighter>();
 	return nullptr;
 }
 static std::string
 shebang_to_ft(std::string_view first_line)
 {
 	if (first_line.size() < 2 || first_line.substr(0, 2) != "#!")
 		return "";
 	std::string low = to_lower(first_line);
 	if (low.find("python") != std::string::npos)
 		return "python";
 	if (low.find("bash") != std::string::npos)
 		return "shell";
 	if (low.find("sh") != std::string::npos)
 		return "shell";
 	if (low.find("zsh") != std::string::npos)
 		return "shell";
 	if (low.find("fish") != std::string::npos)
 		return "shell";
 	if (low.find("scheme") != std::string::npos || low.find("racket") != std::string::npos || low.find("guile") !=
 	    std::string::npos)
 		return "lisp";
 	return "";
 }
 std::string
 HighlighterRegistry::DetectForPath(std::string_view path, std::string_view first_line)
 {
 	// Extension
 	std::string p(path);
 	std::error_code ec;
 	std::string ext = std::filesystem::path(p).extension().string();
 	for (auto &ch: ext)
 		ch = static_cast<char>(std::tolower(static_cast<unsigned char>(ch)));
 	if (!ext.empty()) {
 		if (ext == ".c" || ext == ".cc" || ext == ".cpp" || ext == ".cxx" || ext == ".h" || ext == ".hpp" || ext
 		    == ".hh")
 			return "cpp";
 		if (ext == ".json")
 			return "json";
 		if (ext == ".md" || ext == ".markdown" || ext == ".mkd")
 			return "markdown";
 		if (ext == ".sh" || ext == ".bash" || ext == ".zsh" || ext == ".ksh" || ext == ".fish")
 			return "shell";
 		if (ext == ".go")
 			return "go";
 		if (ext == ".py")
 			return "python";
 		if (ext == ".rs")
 			return "rust";
 		if (ext == ".lisp" || ext == ".scm" || ext == ".rkt" || ext == ".el" || ext == ".clj" || ext == ".cljc"
 		    || ext == ".cl")
 			return "lisp";
 		if (ext == ".sql" || ext == ".sqlite")
 			return "sql";
 		if (ext == ".erl" || ext == ".hrl")
 			return "erlang";
 		if (ext == ".forth" || ext == ".fth" || ext == ".4th" || ext == ".fs")
 			return "forth";
 	}
 	// Shebang
 	std::string ft = shebang_to_ft(first_line);
 	return ft;
 }
 } // namespace kte
 // Extensibility API implementations
 namespace kte {
 void
 HighlighterRegistry::Register(std::string_view filetype, Factory factory, bool override_existing)
 {
 	std::string ft = Normalize(filetype);
 	for (auto &e: registry()) {
 		if (e.ft == ft) {
 			if (override_existing)
 				e.factory = std::move(factory);
 			return;
 		}
 	}
 	registry().push_back(RegEntry{ft, std::move(factory)});
 }
 bool
 HighlighterRegistry::IsRegistered(std::string_view filetype)
 {
 	std::string ft = Normalize(filetype);
 	for (const auto &e: registry())
 		if (e.ft == ft)
 			return true;
 	return false;
 }
 std::vector<std::string>
 HighlighterRegistry::RegisteredFiletypes()
 {
 	std::vector<std::string> out;
 	out.reserve(registry().size());
 	for (const auto &e: registry())
 		out.push_back(e.ft);
 	return out;
 }
 #ifdef KTE_ENABLE_TREESITTER
 // Forward declare adapter factory
 std::unique_ptr<LanguageHighlighter> CreateTreeSitterHighlighter(const char *filetype,
                                                                 const void * (*get_lang)());
 void
 HighlighterRegistry::RegisterTreeSitter(std::string_view filetype,
                                        const TSLanguage * (*get_language)())
 {
 	std::string ft = Normalize(filetype);
 	Register(ft, [ft, get_language]() {
 		return CreateTreeSitterHighlighter(ft.c_str(), reinterpret_cast<const void* (*)()>(get_language));
 	}, /*override_existing=*/true);
 }
 #endif
 } // namespace kte
--- a/syntax/HighlighterRegistry.h
+++ b/syntax/HighlighterRegistry.h
@@ -0,0 +1,47 @@
 // HighlighterRegistry.h - create/detect language highlighters and allow external registration
 #pragma once
 #include <functional>
 #include <memory>
 #include <string>
 #include <string_view>
 #include <vector>
 #include "LanguageHighlighter.h"
 namespace kte {
 class HighlighterRegistry {
 public:
 	using Factory = std::function<std::unique_ptr<LanguageHighlighter>()>;
 	// Create a highlighter for normalized filetype id (e.g., "cpp", "json", "markdown", "shell", "go", "python", "rust", "lisp").
 	static std::unique_ptr<LanguageHighlighter> CreateFor(std::string_view filetype);
 	// Detect filetype by path extension and shebang (first line).
 	// Returns normalized id or empty string if unknown.
 	static std::string DetectForPath(std::string_view path, std::string_view first_line);
 	// Normalize various aliases/extensions to canonical ids.
 	static std::string Normalize(std::string_view ft);
 	// Extensibility: allow external code to register highlighters at runtime.
 	// The filetype key is normalized via Normalize(). If a factory is already registered for the
 	// normalized key and override=false, the existing factory is kept.
 	static void Register(std::string_view filetype, Factory factory, bool override_existing = true);
 	// Returns true if a factory is registered for the (normalized) filetype.
 	static bool IsRegistered(std::string_view filetype);
 	// Return a list of currently registered (normalized) filetypes. Primarily for diagnostics/tests.
 	static std::vector<std::string> RegisteredFiletypes();
 #ifdef KTE_ENABLE_TREESITTER
 	// Forward declaration to avoid hard dependency when disabled.
 	struct TSLanguage;
 	// Convenience: register a Tree-sitter-backed highlighter for a filetype.
 	// The getter should return a non-null language pointer for the grammar.
 	static void RegisterTreeSitter(std::string_view filetype,
 	                               const TSLanguage * (*get_language)());
 #endif
 };
 } // namespace kte
--- a/syntax/JsonHighlighter.cc
+++ b/syntax/JsonHighlighter.cc
@@ -0,0 +1,90 @@
 #include "JsonHighlighter.h"
 #include "../Buffer.h"
 #include <cctype>
 namespace kte {
 static bool
 is_digit(char c)
 {
 	return c >= '0' && c <= '9';
 }
 void
 JSONHighlighter::HighlightLine(const Buffer &buf, int row, std::vector<HighlightSpan> &out) const
 {
 	const auto &rows = buf.Rows();
 	if (row < 0 || static_cast<std::size_t>(row) >= rows.size())
 		return;
 	std::string s = static_cast<std::string>(rows[static_cast<std::size_t>(row)]);
 	int n         = static_cast<int>(s.size());
 	auto push     = [&](int a, int b, TokenKind k) {
 		if (b > a)
 			out.push_back({a, b, k});
 	};
 	int i = 0;
 	while (i < n) {
 		char c = s[i];
 		if (c == ' ' || c == '\t') {
 			int j = i + 1;
 			while (j < n && (s[j] == ' ' || s[j] == '\t'))
 				++j;
 			push(i, j, TokenKind::Whitespace);
 			i = j;
 			continue;
 		}
 		if (c == '"') {
 			int j    = i + 1;
 			bool esc = false;
 			while (j < n) {
 				char d = s[j++];
 				if (esc) {
 					esc = false;
 					continue;
 				}
 				if (d == '\\') {
 					esc = true;
 					continue;
 				}
 				if (d == '"')
 					break;
 			}
 			push(i, j, TokenKind::String);
 			i = j;
 			continue;
 		}
 		if (is_digit(c) || (c == '-' && i + 1 < n && is_digit(s[i + 1]))) {
 			int j = i + 1;
 			while (j < n && (std::isdigit(static_cast<unsigned char>(s[j])) || s[j] == '.' || s[j] == 'e' ||
 			                 s[j] == 'E' || s[j] == '+' || s[j] == '-' || s[j] == '_'))
 				++j;
 			push(i, j, TokenKind::Number);
 			i = j;
 			continue;
 		}
 		// booleans/null
 		if (std::isalpha(static_cast<unsigned char>(c))) {
 			int j = i + 1;
 			while (j < n && std::isalpha(static_cast<unsigned char>(s[j])))
 				++j;
 			std::string id = s.substr(i, j - i);
 			if (id == "true" || id == "false" || id == "null")
 				push(i, j, TokenKind::Constant);
 			else
 				push(i, j, TokenKind::Identifier);
 			i = j;
 			continue;
 		}
 		// punctuation
 		if (c == '{' || c == '}' || c == '[' || c == ']' || c == ',' || c == ':') {
 			push(i, i + 1, TokenKind::Punctuation);
 			++i;
 			continue;
 		}
 		// fallback
 		push(i, i + 1, TokenKind::Default);
 		++i;
 	}
 }
 } // namespace kte
--- a/syntax/JsonHighlighter.h
+++ b/syntax/JsonHighlighter.h
@@ -0,0 +1,12 @@
 // JsonHighlighter.h - simple JSON line highlighter
 #pragma once
 #include "LanguageHighlighter.h"
 #include <vector>
 namespace kte {
 class JSONHighlighter final : public LanguageHighlighter {
 public:
 	void HighlightLine(const Buffer &buf, int row, std::vector<HighlightSpan> &out) const override;
 };
 } // namespace kte
--- a/syntax/LanguageHighlighter.h
+++ b/syntax/LanguageHighlighter.h
@@ -0,0 +1,51 @@
 // LanguageHighlighter.h - interface for line-based highlighters
 #pragma once
 #include <memory>
 #include <vector>
 #include <string>
 #include "../Highlight.h"
 class Buffer;
 namespace kte {
 class LanguageHighlighter {
 public:
 	virtual ~LanguageHighlighter() = default;
 	// Produce highlight spans for a given buffer row. Implementations should append to out.
 	virtual void HighlightLine(const Buffer &buf, int row, std::vector<HighlightSpan> &out) const = 0;
 	virtual bool Stateful() const
 	{
 		return false;
 	}
 };
 // Optional extension for stateful highlighters (e.g., multi-line comments/strings).
 // Engines may detect and use this via dynamic_cast without breaking stateless impls.
 class StatefulHighlighter : public LanguageHighlighter {
 public:
 	struct LineState {
 		bool in_block_comment{false};
 		bool in_raw_string{false};
 		// For raw strings, remember the delimiter between the opening R"delim( and closing )delim"
 		std::string raw_delim;
 	};
 	// Highlight one line given the previous line state; return the resulting state after this line.
 	// Implementations should append spans for this line to out and compute the next state.
 	virtual LineState HighlightLineStateful(const Buffer &buf,
 	                                        int row,
 	                                        const LineState &prev,
 	                                        std::vector<HighlightSpan> &out) const = 0;
 	bool Stateful() const override
 	{
 		return true;
 	}
 };
 } // namespace kte
--- a/syntax/LispHighlighter.cc
+++ b/syntax/LispHighlighter.cc
@@ -0,0 +1,107 @@
 #include "LispHighlighter.h"
 #include "../Buffer.h"
 #include <cctype>
 namespace kte {
 static void
 push(std::vector<HighlightSpan> &out, int a, int b, TokenKind k)
 {
 	if (b > a)
 		out.push_back({a, b, k});
 }
 LispHighlighter::LispHighlighter()
 {
 	const char *kw[] = {
 		"defun", "lambda", "let", "let*", "define", "set!", "if", "cond", "begin", "quote", "quasiquote",
 		"unquote", "unquote-splicing", "loop", "do", "and", "or", "not"
 	};
 	for (auto s: kw)
 		kws_.insert(s);
 }
 void
 LispHighlighter::HighlightLine(const Buffer &buf, int row, std::vector<HighlightSpan> &out) const
 {
 	const auto &rows = buf.Rows();
 	if (row < 0 || static_cast<std::size_t>(row) >= rows.size())
 		return;
 	std::string s = static_cast<std::string>(rows[static_cast<std::size_t>(row)]);
 	int n         = static_cast<int>(s.size());
 	int i         = 0;
 	int bol       = 0;
 	while (bol < n && (s[bol] == ' ' || s[bol] == '\t'))
 		++bol;
 	if (bol < n && s[bol] == ';') {
 		push(out, bol, n, TokenKind::Comment);
 		if (bol > 0)
 			push(out, 0, bol, TokenKind::Whitespace);
 		return;
 	}
 	while (i < n) {
 		char c = s[i];
 		if (c == ' ' || c == '\t') {
 			int j = i + 1;
 			while (j < n && (s[j] == ' ' || s[j] == '\t'))
 				++j;
 			push(out, i, j, TokenKind::Whitespace);
 			i = j;
 			continue;
 		}
 		if (c == ';') {
 			push(out, i, n, TokenKind::Comment);
 			break;
 		}
 		if (c == '"') {
 			int j    = i + 1;
 			bool esc = false;
 			while (j < n) {
 				char d = s[j++];
 				if (esc) {
 					esc = false;
 					continue;
 				}
 				if (d == '\\') {
 					esc = true;
 					continue;
 				}
 				if (d == '"')
 					break;
 			}
 			push(out, i, j, TokenKind::String);
 			i = j;
 			continue;
 		}
 		if (std::isalpha(static_cast<unsigned char>(c)) || c == '*' || c == '-' || c == '+' || c == '/' || c ==
 		    '_') {
 			int j = i + 1;
 			while (j < n && (std::isalnum(static_cast<unsigned char>(s[j])) || s[j] == '*' || s[j] == '-' ||
 			                 s[j] == '+' || s[j] == '/' || s[j] == '_' || s[j] == '!'))
 				++j;
 			std::string id = s.substr(i, j - i);
 			TokenKind k    = kws_.count(id) ? TokenKind::Keyword : TokenKind::Identifier;
 			push(out, i, j, k);
 			i = j;
 			continue;
 		}
 		if (std::isdigit(static_cast<unsigned char>(c))) {
 			int j = i + 1;
 			while (j < n && (std::isdigit(static_cast<unsigned char>(s[j])) || s[j] == '.'))
 				++j;
 			push(out, i, j, TokenKind::Number);
 			i = j;
 			continue;
 		}
 		if (std::ispunct(static_cast<unsigned char>(c))) {
 			TokenKind k = TokenKind::Punctuation;
 			push(out, i, i + 1, k);
 			++i;
 			continue;
 		}
 		push(out, i, i + 1, TokenKind::Default);
 		++i;
 	}
 }
 } // namespace kte
--- a/syntax/LispHighlighter.h
+++ b/syntax/LispHighlighter.h
@@ -0,0 +1,17 @@
 // LispHighlighter.h - simple Lisp/Scheme family highlighter
 #pragma once
 #include "LanguageHighlighter.h"
 #include <unordered_set>
 namespace kte {
 class LispHighlighter final : public LanguageHighlighter {
 public:
 	LispHighlighter();
 	void HighlightLine(const Buffer &buf, int row, std::vector<HighlightSpan> &out) const override;
 private:
 	std::unordered_set<std::string> kws_;
 };
 } // namespace kte
--- a/syntax/MarkdownHighlighter.cc
+++ b/syntax/MarkdownHighlighter.cc
@@ -0,0 +1,132 @@
 #include "MarkdownHighlighter.h"
 #include "../Buffer.h"
 #include <cctype>
 namespace kte {
 static void
 push_span(std::vector<HighlightSpan> &out, int a, int b, TokenKind k)
 {
 	if (b > a)
 		out.push_back({a, b, k});
 }
 void
 MarkdownHighlighter::HighlightLine(const Buffer &buf, int row, std::vector<HighlightSpan> &out) const
 {
 	LineState st; // not used in stateless entry
 	(void) HighlightLineStateful(buf, row, st, out);
 }
 StatefulHighlighter::LineState
 MarkdownHighlighter::HighlightLineStateful(const Buffer &buf, int row, const LineState &prev,
                                           std::vector<HighlightSpan> &out) const
 {
 	StatefulHighlighter::LineState state = prev;
 	const auto &rows                     = buf.Rows();
 	if (row < 0 || static_cast<std::size_t>(row) >= rows.size())
 		return state;
 	std::string s = static_cast<std::string>(rows[static_cast<std::size_t>(row)]);
 	int n         = static_cast<int>(s.size());
 	// Reuse in_block_comment flag as "in fenced code" state.
 	if (state.in_block_comment) {
 		// If line contains closing fence ``` then close after it
 		auto pos = s.find("```");
 		if (pos == std::string::npos) {
 			push_span(out, 0, n, TokenKind::String);
 			state.in_block_comment = true;
 			return state;
 		} else {
 			int end = static_cast<int>(pos + 3);
 			push_span(out, 0, end, TokenKind::String);
 			// rest of line processed normally after fence
 			int i = end;
 			// whitespace
 			if (i < n)
 				push_span(out, i, n, TokenKind::Default);
 			state.in_block_comment = false;
 			return state;
 		}
 	}
 	// Detect fenced code block start at beginning (allow leading spaces)
 	int bol = 0;
 	while (bol < n && (s[bol] == ' ' || s[bol] == '\t'))
 		++bol;
 	if (bol + 3 <= n && s.compare(bol, 3, "```") == 0) {
 		push_span(out, bol, n, TokenKind::String);
 		state.in_block_comment = true; // enter fenced mode
 		return state;
 	}
 	// Headings: lines starting with 1-6 '#'
 	if (bol < n && s[bol] == '#') {
 		int j = bol;
 		while (j < n && s[j] == '#')
 			++j; // hashes
 		// include following space and text as Keyword to stand out
 		push_span(out, bol, n, TokenKind::Keyword);
 		return state;
 	}
 	// Process inline: emphasis and code spans
 	int i = 0;
 	while (i < n) {
 		char c = s[i];
 		if (c == '`') {
 			int j = i + 1;
 			while (j < n && s[j] != '`')
 				++j;
 			if (j < n)
 				++j;
 			push_span(out, i, j, TokenKind::String);
 			i = j;
 			continue;
 		}
 		if (c == '*' || c == '_') {
 			// bold/italic markers: treat the marker and until next same marker as Type to highlight
 			char m = c;
 			int j  = i + 1;
 			while (j < n && s[j] != m)
 				++j;
 			if (j < n)
 				++j;
 			push_span(out, i, j, TokenKind::Type);
 			i = j;
 			continue;
 		}
 		// links []() minimal: treat [text](url) as Function
 		if (c == '[') {
 			int j = i + 1;
 			while (j < n && s[j] != ']')
 				++j;
 			if (j < n)
 				++j; // include ]
 			if (j < n && s[j] == '(') {
 				while (j < n && s[j] != ')')
 					++j;
 				if (j < n)
 					++j;
 			}
 			push_span(out, i, j, TokenKind::Function);
 			i = j;
 			continue;
 		}
 		// whitespace
 		if (c == ' ' || c == '\t') {
 			int j = i + 1;
 			while (j < n && (s[j] == ' ' || s[j] == '\t'))
 				++j;
 			push_span(out, i, j, TokenKind::Whitespace);
 			i = j;
 			continue;
 		}
 		// fallback: default single char
 		push_span(out, i, i + 1, TokenKind::Default);
 		++i;
 	}
 	return state;
 }
 } // namespace kte
--- a/syntax/MarkdownHighlighter.h
+++ b/syntax/MarkdownHighlighter.h
@@ -0,0 +1,14 @@
 // MarkdownHighlighter.h - simple Markdown highlighter
 #pragma once
 #include "LanguageHighlighter.h"
 namespace kte {
 class MarkdownHighlighter final : public StatefulHighlighter {
 public:
 	void HighlightLine(const Buffer &buf, int row, std::vector<HighlightSpan> &out) const override;
 	LineState HighlightLineStateful(const Buffer &buf, int row, const LineState &prev,
 	                                std::vector<HighlightSpan> &out) const override;
 };
 } // namespace kte
--- a/syntax/NullHighlighter.cc
+++ b/syntax/NullHighlighter.cc
@@ -0,0 +1,17 @@
 #include "NullHighlighter.h"
 #include "../Buffer.h"
 namespace kte {
 void
 NullHighlighter::HighlightLine(const Buffer &buf, int row, std::vector<HighlightSpan> &out) const
 {
 	const auto &rows = buf.Rows();
 	if (row < 0 || static_cast<std::size_t>(row) >= rows.size())
 		return;
 	std::string s = static_cast<std::string>(rows[static_cast<std::size_t>(row)]);
 	int n         = static_cast<int>(s.size());
 	if (n <= 0)
 		return;
 	out.push_back({0, n, TokenKind::Default});
 }
 } // namespace kte
--- a/syntax/NullHighlighter.h
+++ b/syntax/NullHighlighter.h
@@ -0,0 +1,11 @@
 // NullHighlighter.h - default highlighter that emits a single Default span per line
 #pragma once
 #include "LanguageHighlighter.h"
 namespace kte {
 class NullHighlighter final : public LanguageHighlighter {
 public:
 	void HighlightLine(const Buffer &buf, int row, std::vector<HighlightSpan> &out) const override;
 };
 } // namespace kte
--- a/syntax/PythonHighlighter.cc
+++ b/syntax/PythonHighlighter.cc
@@ -0,0 +1,172 @@
 #include "PythonHighlighter.h"
 #include "../Buffer.h"
 #include <cctype>
 namespace kte {
 static void
 push(std::vector<HighlightSpan> &out, int a, int b, TokenKind k)
 {
 	if (b > a)
 		out.push_back({a, b, k});
 }
 static bool
 is_ident_start(char c)
 {
 	return std::isalpha(static_cast<unsigned char>(c)) || c == '_';
 }
 static bool
 is_ident_char(char c)
 {
 	return std::isalnum(static_cast<unsigned char>(c)) || c == '_';
 }
 PythonHighlighter::PythonHighlighter()
 {
 	const char *kw[] = {
 		"and", "as", "assert", "break", "class", "continue", "def", "del", "elif", "else", "except", "False",
 		"finally", "for", "from", "global", "if", "import", "in", "is", "lambda", "None", "nonlocal", "not",
 		"or", "pass", "raise", "return", "True", "try", "while", "with", "yield"
 	};
 	for (auto s: kw)
 		kws_.insert(s);
 }
 void
 PythonHighlighter::HighlightLine(const Buffer &buf, int row, std::vector<HighlightSpan> &out) const
 {
 	LineState st;
 	(void) HighlightLineStateful(buf, row, st, out);
 }
 StatefulHighlighter::LineState
 PythonHighlighter::HighlightLineStateful(const Buffer &buf, int row, const LineState &prev,
                                         std::vector<HighlightSpan> &out) const
 {
 	StatefulHighlighter::LineState state = prev;
 	const auto &rows                     = buf.Rows();
 	if (row < 0 || static_cast<std::size_t>(row) >= rows.size())
 		return state;
 	std::string s = static_cast<std::string>(rows[static_cast<std::size_t>(row)]);
 	int n         = static_cast<int>(s.size());
 	// Triple-quoted string continuation uses in_raw_string with raw_delim either "'''" or "\"\"\""
 	if (state.in_raw_string && (state.raw_delim == "'''" || state.raw_delim == "\"\"\"")) {
 		auto pos = s.find(state.raw_delim);
 		if (pos == std::string::npos) {
 			push(out, 0, n, TokenKind::String);
 			return state; // still inside
 		} else {
 			int end = static_cast<int>(pos + static_cast<int>(state.raw_delim.size()));
 			push(out, 0, end, TokenKind::String);
 			// remainder processed normally
 			s                   = s.substr(end);
 			n                   = static_cast<int>(s.size());
 			state.in_raw_string = false;
 			state.raw_delim.clear();
 			// Continue parsing remainder as a separate small loop
 			int base = end;
 			// original offset, but we already emitted to 'out' with base=0; following spans should be from 'end'
 			// For simplicity, mark rest as Default
 			if (n > 0)
 				push(out, base, base + n, TokenKind::Default);
 			return state;
 		}
 	}
 	int i = 0;
 	// Detect comment start '#', ignoring inside strings
 	while (i < n) {
 		char c = s[i];
 		if (c == ' ' || c == '\t') {
 			int j = i + 1;
 			while (j < n && (s[j] == ' ' || s[j] == '\t'))
 				++j;
 			push(out, i, j, TokenKind::Whitespace);
 			i = j;
 			continue;
 		}
 		if (c == '#') {
 			push(out, i, n, TokenKind::Comment);
 			break;
 		}
 		// Strings: triple quotes and single-line
 		if (c == '"' || c == '\'') {
 			char q = c;
 			// triple?
 			if (i + 2 < n && s[i + 1] == q && s[i + 2] == q) {
 				std::string delim(3, q);
 				int j    = i + 3; // search for closing triple
 				auto pos = s.find(delim, static_cast<std::size_t>(j));
 				if (pos == std::string::npos) {
 					push(out, i, n, TokenKind::String);
 					state.in_raw_string = true;
 					state.raw_delim     = delim;
 					return state;
 				} else {
 					int end = static_cast<int>(pos + 3);
 					push(out, i, end, TokenKind::String);
 					i = end;
 					continue;
 				}
 			} else {
 				int j    = i + 1;
 				bool esc = false;
 				while (j < n) {
 					char d = s[j++];
 					if (esc) {
 						esc = false;
 						continue;
 					}
 					if (d == '\\') {
 						esc = true;
 						continue;
 					}
 					if (d == q)
 						break;
 				}
 				push(out, i, j, TokenKind::String);
 				i = j;
 				continue;
 			}
 		}
 		if (std::isdigit(static_cast<unsigned char>(c))) {
 			int j = i + 1;
 			while (j < n && (std::isalnum(static_cast<unsigned char>(s[j])) || s[j] == '.' || s[j] == '_'))
 				++j;
 			push(out, i, j, TokenKind::Number);
 			i = j;
 			continue;
 		}
 		if (is_ident_start(c)) {
 			int j = i + 1;
 			while (j < n && is_ident_char(s[j]))
 				++j;
 			std::string id = s.substr(i, j - i);
 			TokenKind k    = TokenKind::Identifier;
 			if (kws_.count(id))
 				k = TokenKind::Keyword;
 			push(out, i, j, k);
 			i = j;
 			continue;
 		}
 		if (std::ispunct(static_cast<unsigned char>(c))) {
 			TokenKind k = TokenKind::Operator;
 			if (c == ':' || c == ',' || c == '(' || c == ')' || c == '[' || c == ']')
 				k = TokenKind::Punctuation;
 			push(out, i, i + 1, k);
 			++i;
 			continue;
 		}
 		push(out, i, i + 1, TokenKind::Default);
 		++i;
 	}
 	return state;
 }
 } // namespace kte
--- a/syntax/PythonHighlighter.h
+++ b/syntax/PythonHighlighter.h
@@ -0,0 +1,20 @@
 // PythonHighlighter.h - simple Python highlighter with triple-quote state
 #pragma once
 #include "LanguageHighlighter.h"
 #include <unordered_set>
 namespace kte {
 class PythonHighlighter final : public StatefulHighlighter {
 public:
 	PythonHighlighter();
 	void HighlightLine(const Buffer &buf, int row, std::vector<HighlightSpan> &out) const override;
 	LineState HighlightLineStateful(const Buffer &buf, int row, const LineState &prev,
 	                                std::vector<HighlightSpan> &out) const override;
 private:
 	std::unordered_set<std::string> kws_;
 };
 } // namespace kte
--- a/syntax/RustHighlighter.cc
+++ b/syntax/RustHighlighter.cc
@@ -0,0 +1,145 @@
 #include "RustHighlighter.h"
 #include "../Buffer.h"
 #include <cctype>
 namespace kte {
 static void
 push(std::vector<HighlightSpan> &out, int a, int b, TokenKind k)
 {
 	if (b > a)
 		out.push_back({a, b, k});
 }
 static bool
 is_ident_start(char c)
 {
 	return std::isalpha(static_cast<unsigned char>(c)) || c == '_';
 }
 static bool
 is_ident_char(char c)
 {
 	return std::isalnum(static_cast<unsigned char>(c)) || c == '_';
 }
 RustHighlighter::RustHighlighter()
 {
 	const char *kw[] = {
 		"as", "break", "const", "continue", "crate", "else", "enum", "extern", "false", "fn", "for", "if",
 		"impl", "in", "let", "loop", "match", "mod", "move", "mut", "pub", "ref", "return", "self", "Self",
 		"static", "struct", "super", "trait", "true", "type", "unsafe", "use", "where", "while", "dyn", "async",
 		"await", "try"
 	};
 	for (auto s: kw)
 		kws_.insert(s);
 	const char *tp[] = {
 		"u8", "u16", "u32", "u64", "u128", "usize", "i8", "i16", "i32", "i64", "i128", "isize", "f32", "f64",
 		"bool", "char", "str"
 	};
 	for (auto s: tp)
 		types_.insert(s);
 }
 void
 RustHighlighter::HighlightLine(const Buffer &buf, int row, std::vector<HighlightSpan> &out) const
 {
 	const auto &rows = buf.Rows();
 	if (row < 0 || static_cast<std::size_t>(row) >= rows.size())
 		return;
 	std::string s = static_cast<std::string>(rows[static_cast<std::size_t>(row)]);
 	int n         = static_cast<int>(s.size());
 	int i         = 0;
 	while (i < n) {
 		char c = s[i];
 		if (c == ' ' || c == '\t') {
 			int j = i + 1;
 			while (j < n && (s[j] == ' ' || s[j] == '\t'))
 				++j;
 			push(out, i, j, TokenKind::Whitespace);
 			i = j;
 			continue;
 		}
 		if (c == '/' && i + 1 < n && s[i + 1] == '/') {
 			push(out, i, n, TokenKind::Comment);
 			break;
 		}
 		if (c == '/' && i + 1 < n && s[i + 1] == '*') {
 			int j       = i + 2;
 			bool closed = false;
 			while (j + 1 <= n) {
 				if (j + 1 < n && s[j] == '*' && s[j + 1] == '/') {
 					j += 2;
 					closed = true;
 					break;
 				}
 				++j;
 			}
 			if (!closed) {
 				push(out, i, n, TokenKind::Comment);
 				break;
 			} else {
 				push(out, i, j, TokenKind::Comment);
 				i = j;
 				continue;
 			}
 		}
 		if (c == '"') {
 			int j    = i + 1;
 			bool esc = false;
 			while (j < n) {
 				char d = s[j++];
 				if (esc) {
 					esc = false;
 					continue;
 				}
 				if (d == '\\') {
 					esc = true;
 					continue;
 				}
 				if (d == '"')
 					break;
 			}
 			push(out, i, j, TokenKind::String);
 			i = j;
 			continue;
 		}
 		if (std::isdigit(static_cast<unsigned char>(c))) {
 			int j = i + 1;
 			while (j < n && (std::isalnum(static_cast<unsigned char>(s[j])) || s[j] == '.' || s[j] == '_'))
 				++j;
 			push(out, i, j, TokenKind::Number);
 			i = j;
 			continue;
 		}
 		if (is_ident_start(c)) {
 			int j = i + 1;
 			while (j < n && is_ident_char(s[j]))
 				++j;
 			std::string id = s.substr(i, j - i);
 			TokenKind k    = TokenKind::Identifier;
 			if (kws_.count(id))
 				k = TokenKind::Keyword;
 			else if (types_.count(id))
 				k = TokenKind::Type;
 			push(out, i, j, k);
 			i = j;
 			continue;
 		}
 		if (std::ispunct(static_cast<unsigned char>(c))) {
 			TokenKind k = TokenKind::Operator;
 			if (c == ';' || c == ',' || c == '(' || c == ')' || c == '{' || c == '}' || c == '[' || c ==
 			    ']')
 				k = TokenKind::Punctuation;
 			push(out, i, i + 1, k);
 			++i;
 			continue;
 		}
 		push(out, i, i + 1, TokenKind::Default);
 		++i;
 	}
 }
 } // namespace kte
--- a/syntax/RustHighlighter.h
+++ b/syntax/RustHighlighter.h
@@ -0,0 +1,18 @@
 // RustHighlighter.h - simple Rust highlighter
 #pragma once
 #include "LanguageHighlighter.h"
 #include <unordered_set>
 namespace kte {
 class RustHighlighter final : public LanguageHighlighter {
 public:
 	RustHighlighter();
 	void HighlightLine(const Buffer &buf, int row, std::vector<HighlightSpan> &out) const override;
 private:
 	std::unordered_set<std::string> kws_;
 	std::unordered_set<std::string> types_;
 };
 } // namespace kte
--- a/syntax/ShellHighlighter.cc
+++ b/syntax/ShellHighlighter.cc
@@ -0,0 +1,105 @@
 #include "ShellHighlighter.h"
 #include "../Buffer.h"
 #include <cctype>
 namespace kte {
 static void
 push(std::vector<HighlightSpan> &out, int a, int b, TokenKind k)
 {
 	if (b > a)
 		out.push_back({a, b, k});
 }
 void
 ShellHighlighter::HighlightLine(const Buffer &buf, int row, std::vector<HighlightSpan> &out) const
 {
 	const auto &rows = buf.Rows();
 	if (row < 0 || static_cast<std::size_t>(row) >= rows.size())
 		return;
 	std::string s = static_cast<std::string>(rows[static_cast<std::size_t>(row)]);
 	int n         = static_cast<int>(s.size());
 	int i         = 0;
 	// if first non-space is '#', whole line is comment
 	int bol = 0;
 	while (bol < n && (s[bol] == ' ' || s[bol] == '\t'))
 		++bol;
 	if (bol < n && s[bol] == '#') {
 		push(out, bol, n, TokenKind::Comment);
 		if (bol > 0)
 			push(out, 0, bol, TokenKind::Whitespace);
 		return;
 	}
 	while (i < n) {
 		char c = s[i];
 		if (c == ' ' || c == '\t') {
 			int j = i + 1;
 			while (j < n && (s[j] == ' ' || s[j] == '\t'))
 				++j;
 			push(out, i, j, TokenKind::Whitespace);
 			i = j;
 			continue;
 		}
 		if (c == '#') {
 			push(out, i, n, TokenKind::Comment);
 			break;
 		}
 		if (c == '\'' || c == '"') {
 			char q   = c;
 			int j    = i + 1;
 			bool esc = false;
 			while (j < n) {
 				char d = s[j++];
 				if (q == '"') {
 					if (esc) {
 						esc = false;
 						continue;
 					}
 					if (d == '\\') {
 						esc = true;
 						continue;
 					}
 					if (d == '"')
 						break;
 				} else {
 					if (d == '\'')
 						break;
 				}
 			}
 			push(out, i, j, TokenKind::String);
 			i = j;
 			continue;
 		}
 		// simple keywords
 		if (std::isalpha(static_cast<unsigned char>(c))) {
 			int j = i + 1;
 			while (j < n && (std::isalnum(static_cast<unsigned char>(s[j])) || s[j] == '_'))
 				++j;
 			std::string id           = s.substr(i, j - i);
 			static const char *kws[] = {
 				"if", "then", "fi", "for", "in", "do", "done", "case", "esac", "while", "function",
 				"elif", "else"
 			};
 			bool kw = false;
 			for (auto k: kws)
 				if (id == k) {
 					kw = true;
 					break;
 				}
 			push(out, i, j, kw ? TokenKind::Keyword : TokenKind::Identifier);
 			i = j;
 			continue;
 		}
 		if (std::ispunct(static_cast<unsigned char>(c))) {
 			TokenKind k = TokenKind::Operator;
 			if (c == '(' || c == ')' || c == '{' || c == '}' || c == ',' || c == ';')
 				k = TokenKind::Punctuation;
 			push(out, i, i + 1, k);
 			++i;
 			continue;
 		}
 		push(out, i, i + 1, TokenKind::Default);
 		++i;
 	}
 }
 } // namespace kte
--- a/syntax/ShellHighlighter.h
+++ b/syntax/ShellHighlighter.h
@@ -0,0 +1,11 @@
 // ShellHighlighter.h - simple POSIX shell highlighter
 #pragma once
 #include "LanguageHighlighter.h"
 namespace kte {
 class ShellHighlighter final : public LanguageHighlighter {
 public:
 	void HighlightLine(const Buffer &buf, int row, std::vector<HighlightSpan> &out) const override;
 };
 } // namespace kte
--- a/syntax/SqlHighlighter.cc
+++ b/syntax/SqlHighlighter.cc
@@ -0,0 +1,156 @@
 #include "SqlHighlighter.h"
 #include "../Buffer.h"
 #include <cctype>
 namespace kte {
 static void
 push(std::vector<HighlightSpan> &out, int a, int b, TokenKind k)
 {
 	if (b > a)
 		out.push_back({a, b, k});
 }
 static bool
 is_ident_start(char c)
 {
 	return std::isalpha(static_cast<unsigned char>(c)) || c == '_';
 }
 static bool
 is_ident_char(char c)
 {
 	return std::isalnum(static_cast<unsigned char>(c)) || c == '_' || c == '$';
 }
 SqlHighlighter::SqlHighlighter()
 {
 	const char *kw[] = {
 		"select", "insert", "update", "delete", "from", "where", "group", "by", "order", "limit",
 		"offset", "values", "into", "create", "table", "index", "unique", "on", "as", "and", "or",
 		"not", "null", "is", "primary", "key", "constraint", "foreign", "references", "drop", "alter",
 		"add", "column", "rename", "to", "if", "exists", "join", "left", "right", "inner", "outer",
 		"cross", "using", "set", "distinct", "having", "union", "all", "case", "when", "then", "else",
 		"end", "pragma", "transaction", "begin", "commit", "rollback", "replace"
 	};
 	for (auto s: kw)
 		kws_.insert(s);
 	const char *types[] = {"integer", "real", "text", "blob", "numeric", "boolean", "date", "datetime"};
 	for (auto s: types)
 		types_.insert(s);
 }
 void
 SqlHighlighter::HighlightLine(const Buffer &buf, int row, std::vector<HighlightSpan> &out) const
 {
 	const auto &rows = buf.Rows();
 	if (row < 0 || static_cast<std::size_t>(row) >= rows.size())
 		return;
 	std::string s = static_cast<std::string>(rows[static_cast<std::size_t>(row)]);
 	int n         = static_cast<int>(s.size());
 	int i         = 0;
 	while (i < n) {
 		char c = s[i];
 		if (c == ' ' || c == '\t') {
 			int j = i + 1;
 			while (j < n && (s[j] == ' ' || s[j] == '\t'))
 				++j;
 			push(out, i, j, TokenKind::Whitespace);
 			i = j;
 			continue;
 		}
 		// line comments: -- ...
 		if (c == '-' && i + 1 < n && s[i + 1] == '-') {
 			push(out, i, n, TokenKind::Comment);
 			break;
 		}
 		// simple block comment on same line: /* ... */
 		if (c == '/' && i + 1 < n && s[i + 1] == '*') {
 			int j       = i + 2;
 			bool closed = false;
 			while (j + 1 <= n) {
 				if (j + 1 < n && s[j] == '*' && s[j + 1] == '/') {
 					j += 2;
 					closed = true;
 					break;
 				}
 				++j;
 			}
 			if (!closed) {
 				push(out, i, n, TokenKind::Comment);
 				break;
 			} else {
 				push(out, i, j, TokenKind::Comment);
 				i = j;
 				continue;
 			}
 		}
 		// strings: '...' or "..."
 		if (c == '\'' || c == '"') {
 			char q   = c;
 			int j    = i + 1;
 			bool esc = false;
 			while (j < n) {
 				char d = s[j++];
 				if (d == q) {
 					// Handle doubled quote escaping for SQL single quotes
 					if (q == '\'' && j < n && s[j] == '\'') {
 						++j;
 						continue;
 					}
 					break;
 				}
 				if (d == '\\') {
 					esc = !esc;
 				} else {
 					esc = false;
 				}
 			}
 			push(out, i, j, TokenKind::String);
 			i = j;
 			continue;
 		}
 		if (std::isdigit(static_cast<unsigned char>(c))) {
 			int j = i + 1;
 			while (j < n && (std::isalnum(static_cast<unsigned char>(s[j])) || s[j] == '.' || s[j] == '_'))
 				++j;
 			push(out, i, j, TokenKind::Number);
 			i = j;
 			continue;
 		}
 		if (is_ident_start(c)) {
 			int j = i + 1;
 			while (j < n && is_ident_char(s[j]))
 				++j;
 			std::string id = s.substr(i, j - i);
 			std::string lower;
 			lower.reserve(id.size());
 			for (char ch: id)
 				lower.push_back(static_cast<char>(std::tolower(static_cast<unsigned char>(ch))));
 			TokenKind k = TokenKind::Identifier;
 			if (kws_.count(lower))
 				k = TokenKind::Keyword;
 			else if (types_.count(lower))
 				k = TokenKind::Type;
 			push(out, i, j, k);
 			i = j;
 			continue;
 		}
 		if (std::ispunct(static_cast<unsigned char>(c))) {
 			TokenKind k = TokenKind::Operator;
 			if (c == ',' || c == ';' || c == '(' || c == ')')
 				k = TokenKind::Punctuation;
 			push(out, i, i + 1, k);
 			++i;
 			continue;
 		}
 		push(out, i, i + 1, TokenKind::Default);
 		++i;
 	}
 }
 } // namespace kte
--- a/syntax/SqlHighlighter.h
+++ b/syntax/SqlHighlighter.h
@@ -0,0 +1,18 @@
 // SqlHighlighter.h - simple SQL/SQLite highlighter
 #pragma once
 #include "LanguageHighlighter.h"
 #include <unordered_set>
 namespace kte {
 class SqlHighlighter final : public LanguageHighlighter {
 public:
 	SqlHighlighter();
 	void HighlightLine(const Buffer &buf, int row, std::vector<HighlightSpan> &out) const override;
 private:
 	std::unordered_set<std::string> kws_;
 	std::unordered_set<std::string> types_;
 };
 } // namespace kte
--- a/syntax/TreeSitterHighlighter.cc
+++ b/syntax/TreeSitterHighlighter.cc
@@ -0,0 +1,51 @@
 #include "TreeSitterHighlighter.h"
 #ifdef KTE_ENABLE_TREESITTER
 #include "Buffer.h"
 #include <utility>
 namespace kte {
 TreeSitterHighlighter::TreeSitterHighlighter(const TSLanguage *lang, std::string filetype)
 	: language_(lang), filetype_(std::move(filetype)) {}
 TreeSitterHighlighter::~TreeSitterHighlighter()
 {
 	disposeParser();
 }
 void
 TreeSitterHighlighter::ensureParsed(const Buffer & /*buf*/) const
 {
 	// Intentionally a stub to avoid pulling the Tree-sitter API and library by default.
 	// In future, when linking against tree-sitter, initialize parser_, set language_,
 	// and build tree_ from the buffer contents.
 }
 void
 TreeSitterHighlighter::disposeParser() const
 {
 	// Stub; nothing to dispose when not actually creating parser/tree
 }
 void
 TreeSitterHighlighter::HighlightLine(const Buffer &/*buf*/, int /*row*/, std::vector<HighlightSpan> &/*out*/) const
 {
 	// For now, no-op. When tree-sitter is wired, map nodes to TokenKind spans per line.
 }
 std::unique_ptr<LanguageHighlighter>
 CreateTreeSitterHighlighter(const char *filetype,
                            const void * (*get_lang)())
 {
 	const auto *lang = reinterpret_cast<const TSLanguage *>(get_lang ? get_lang() : nullptr);
 	return std::make_unique < TreeSitterHighlighter > (lang, filetype ? std::string(filetype) : std::string());
 }
 } // namespace kte
 #endif // KTE_ENABLE_TREESITTER
--- a/syntax/TreeSitterHighlighter.h
+++ b/syntax/TreeSitterHighlighter.h
@@ -0,0 +1,48 @@
 // TreeSitterHighlighter.h - optional adapter for Tree-sitter (behind KTE_ENABLE_TREESITTER)
 #pragma once
 #ifdef KTE_ENABLE_TREESITTER
 #include <memory>
 #include <string>
 #include <vector>
 #include "LanguageHighlighter.h"
 // Forward-declare Tree-sitter C API to avoid hard coupling in headers if includes are not present
 extern "C" {
 struct TSLanguage;
 struct TSParser;
 struct TSTree;
 }
 namespace kte {
 // A minimal adapter that uses Tree-sitter to parse the whole buffer and then, for now,
 // does very limited token classification. This acts as a scaffold for future richer
 // queries. If no queries are provided, it currently produces no spans (safe fallback).
 class TreeSitterHighlighter : public LanguageHighlighter {
 public:
 	explicit TreeSitterHighlighter(const TSLanguage *lang, std::string filetype);
 	~TreeSitterHighlighter() override;
 	void HighlightLine(const Buffer &buf, int row, std::vector<HighlightSpan> &out) const override;
 private:
 	const TSLanguage *language_{nullptr};
 	std::string filetype_;
 	// Lazy parser to avoid startup cost; mutable to allow creation in const method
 	mutable TSParser *parser_{nullptr};
 	mutable TSTree *tree_{nullptr};
 	void ensureParsed(const Buffer &buf) const;
 	void disposeParser() const;
 };
 // Factory used by HighlighterRegistry when registering via RegisterTreeSitter.
 std::unique_ptr<LanguageHighlighter> CreateTreeSitterHighlighter(const char *filetype,
                                                                 const void * (*get_lang)());
 } // namespace kte
 #endif // KTE_ENABLE_TREESITTER
--- a/themes/EInk.h
+++ b/themes/EInk.h
@@ -0,0 +1,177 @@
 // themes/EInk.h — Monochrome e-ink inspired ImGui themes (header-only)
 #pragma once
 #include "imgui.h"
 #include "ThemeHelpers.h"
 // Expects to be included from GUITheme.h after <imgui.h> and RGBA() helper
 static void
 ApplyEInkImGuiTheme()
 {
 	// E-Ink grayscale palette (light background)
 	const ImVec4 paper  = RGBA(0xF2F2EE); // light paper
 	const ImVec4 bg1    = RGBA(0xE6E6E2);
 	const ImVec4 bg2    = RGBA(0xDADAD5);
 	const ImVec4 bg3    = RGBA(0xCFCFCA);
 	const ImVec4 ink    = RGBA(0x111111); // primary text (near black)
 	const ImVec4 dim    = RGBA(0x666666); // disabled text
 	const ImVec4 border = RGBA(0xB8B8B3);
 	const ImVec4 accent = RGBA(0x222222); // controls/active
 	ImGuiStyle &style      = ImGui::GetStyle();
 	style.WindowPadding    = ImVec2(8.0f, 8.0f);
 	style.FramePadding     = ImVec2(6.0f, 4.0f);
 	style.CellPadding      = ImVec2(6.0f, 4.0f);
 	style.ItemSpacing      = ImVec2(6.0f, 6.0f);
 	style.ItemInnerSpacing = ImVec2(6.0f, 4.0f);
 	style.ScrollbarSize    = 14.0f;
 	style.GrabMinSize      = 10.0f;
 	style.WindowRounding   = 0.0f;
 	style.FrameRounding    = 0.0f;
 	style.PopupRounding    = 0.0f;
 	style.GrabRounding     = 0.0f;
 	style.TabRounding      = 0.0f;
 	style.WindowBorderSize = 1.0f;
 	style.FrameBorderSize  = 1.0f;
 	ImVec4 *colors                         = style.Colors;
 	colors[ImGuiCol_Text]                  = ink;
 	colors[ImGuiCol_TextDisabled]          = ImVec4(dim.x, dim.y, dim.z, 1.0f);
 	colors[ImGuiCol_WindowBg]              = paper;
 	colors[ImGuiCol_ChildBg]               = paper;
 	colors[ImGuiCol_PopupBg]               = ImVec4(bg1.x, bg1.y, bg1.z, 0.98f);
 	colors[ImGuiCol_Border]                = border;
 	colors[ImGuiCol_BorderShadow]          = RGBA(0x000000, 0.0f);
 	colors[ImGuiCol_FrameBg]               = bg2;
 	colors[ImGuiCol_FrameBgHovered]        = bg3;
 	colors[ImGuiCol_FrameBgActive]         = bg1;
 	colors[ImGuiCol_TitleBg]               = bg1;
 	colors[ImGuiCol_TitleBgActive]         = bg2;
 	colors[ImGuiCol_TitleBgCollapsed]      = bg1;
 	colors[ImGuiCol_MenuBarBg]             = bg1;
 	colors[ImGuiCol_ScrollbarBg]           = paper;
 	colors[ImGuiCol_ScrollbarGrab]         = bg3;
 	colors[ImGuiCol_ScrollbarGrabHovered]  = bg2;
 	colors[ImGuiCol_ScrollbarGrabActive]   = bg1;
 	colors[ImGuiCol_CheckMark]             = accent;
 	colors[ImGuiCol_SliderGrab]            = accent;
 	colors[ImGuiCol_SliderGrabActive]      = ink;
 	colors[ImGuiCol_Button]                = bg3;
 	colors[ImGuiCol_ButtonHovered]         = bg2;
 	colors[ImGuiCol_ButtonActive]          = bg1;
 	colors[ImGuiCol_Header]                = bg3;
 	colors[ImGuiCol_HeaderHovered]         = bg2;
 	colors[ImGuiCol_HeaderActive]          = bg2;
 	colors[ImGuiCol_Separator]             = border;
 	colors[ImGuiCol_SeparatorHovered]      = bg2;
 	colors[ImGuiCol_SeparatorActive]       = accent;
 	colors[ImGuiCol_ResizeGrip]            = ImVec4(ink.x, ink.y, ink.z, 0.12f);
 	colors[ImGuiCol_ResizeGripHovered]     = ImVec4(accent.x, accent.y, accent.z, 0.50f);
 	colors[ImGuiCol_ResizeGripActive]      = ink;
 	colors[ImGuiCol_Tab]                   = bg2;
 	colors[ImGuiCol_TabHovered]            = bg1;
 	colors[ImGuiCol_TabActive]             = bg3;
 	colors[ImGuiCol_TabUnfocused]          = bg2;
 	colors[ImGuiCol_TabUnfocusedActive]    = bg3;
 	colors[ImGuiCol_TableHeaderBg]         = bg2;
 	colors[ImGuiCol_TableBorderStrong]     = bg1;
 	colors[ImGuiCol_TableBorderLight]      = ImVec4(bg1.x, bg1.y, bg1.z, 0.6f);
 	colors[ImGuiCol_TableRowBg]            = ImVec4(bg1.x, bg1.y, bg1.z, 0.2f);
 	colors[ImGuiCol_TableRowBgAlt]         = ImVec4(bg1.x, bg1.y, bg1.z, 0.35f);
 	colors[ImGuiCol_TextSelectedBg]        = ImVec4(accent.x, accent.y, accent.z, 0.30f);
 	colors[ImGuiCol_DragDropTarget]        = accent;
 	colors[ImGuiCol_NavHighlight]          = accent;
 	colors[ImGuiCol_NavWindowingHighlight] = ImVec4(ink.x, ink.y, ink.z, 0.70f);
 	colors[ImGuiCol_NavWindowingDimBg]     = ImVec4(0.0f, 0.0f, 0.0f, 0.45f);
 	colors[ImGuiCol_ModalWindowDimBg]      = ImVec4(0.0f, 0.0f, 0.0f, 0.45f);
 	colors[ImGuiCol_PlotLines]             = accent;
 	colors[ImGuiCol_PlotLinesHovered]      = ink;
 	colors[ImGuiCol_PlotHistogram]         = accent;
 	colors[ImGuiCol_PlotHistogramHovered]  = ink;
 }
 static inline void
 ApplyEInkDarkImGuiTheme()
 {
 	// E-Ink dark variant (dark background, light ink)
 	const ImVec4 paper  = RGBA(0x1A1A1A);
 	const ImVec4 bg1    = RGBA(0x222222);
 	const ImVec4 bg2    = RGBA(0x2B2B2B);
 	const ImVec4 bg3    = RGBA(0x343434);
 	const ImVec4 ink    = RGBA(0xEDEDEA);
 	const ImVec4 dim    = RGBA(0xB5B5B3);
 	const ImVec4 border = RGBA(0x444444);
 	const ImVec4 accent = RGBA(0xDDDDDD);
 	ImGuiStyle &style      = ImGui::GetStyle();
 	style.WindowPadding    = ImVec2(8.0f, 8.0f);
 	style.FramePadding     = ImVec2(6.0f, 4.0f);
 	style.CellPadding      = ImVec2(6.0f, 4.0f);
 	style.ItemSpacing      = ImVec2(6.0f, 6.0f);
 	style.ItemInnerSpacing = ImVec2(6.0f, 4.0f);
 	style.ScrollbarSize    = 14.0f;
 	style.GrabMinSize      = 10.0f;
 	style.WindowRounding   = 0.0f;
 	style.FrameRounding    = 0.0f;
 	style.PopupRounding    = 0.0f;
 	style.GrabRounding     = 0.0f;
 	style.TabRounding      = 0.0f;
 	style.WindowBorderSize = 1.0f;
 	style.FrameBorderSize  = 1.0f;
 	ImVec4 *colors                         = style.Colors;
 	colors[ImGuiCol_Text]                  = ink;
 	colors[ImGuiCol_TextDisabled]          = ImVec4(dim.x, dim.y, dim.z, 1.0f);
 	colors[ImGuiCol_WindowBg]              = paper;
 	colors[ImGuiCol_ChildBg]               = paper;
 	colors[ImGuiCol_PopupBg]               = ImVec4(bg1.x, bg1.y, bg1.z, 0.98f);
 	colors[ImGuiCol_Border]                = border;
 	colors[ImGuiCol_BorderShadow]          = RGBA(0x000000, 0.0f);
 	colors[ImGuiCol_FrameBg]               = bg2;
 	colors[ImGuiCol_FrameBgHovered]        = bg3;
 	colors[ImGuiCol_FrameBgActive]         = bg1;
 	colors[ImGuiCol_TitleBg]               = bg1;
 	colors[ImGuiCol_TitleBgActive]         = bg2;
 	colors[ImGuiCol_TitleBgCollapsed]      = bg1;
 	colors[ImGuiCol_MenuBarBg]             = bg1;
 	colors[ImGuiCol_ScrollbarBg]           = paper;
 	colors[ImGuiCol_ScrollbarGrab]         = bg3;
 	colors[ImGuiCol_ScrollbarGrabHovered]  = bg2;
 	colors[ImGuiCol_ScrollbarGrabActive]   = bg1;
 	colors[ImGuiCol_CheckMark]             = accent;
 	colors[ImGuiCol_SliderGrab]            = accent;
 	colors[ImGuiCol_SliderGrabActive]      = ink;
 	colors[ImGuiCol_Button]                = bg3;
 	colors[ImGuiCol_ButtonHovered]         = bg2;
 	colors[ImGuiCol_ButtonActive]          = bg1;
 	colors[ImGuiCol_Header]                = bg3;
 	colors[ImGuiCol_HeaderHovered]         = bg2;
 	colors[ImGuiCol_HeaderActive]          = bg2;
 	colors[ImGuiCol_Separator]             = border;
 	colors[ImGuiCol_SeparatorHovered]      = bg2;
 	colors[ImGuiCol_SeparatorActive]       = accent;
 	colors[ImGuiCol_ResizeGrip]            = ImVec4(ink.x, ink.y, ink.z, 0.12f);
 	colors[ImGuiCol_ResizeGripHovered]     = ImVec4(accent.x, accent.y, accent.z, 0.50f);
 	colors[ImGuiCol_ResizeGripActive]      = ink;
 	colors[ImGuiCol_Tab]                   = bg2;
 	colors[ImGuiCol_TabHovered]            = bg1;
 	colors[ImGuiCol_TabActive]             = bg3;
 	colors[ImGuiCol_TabUnfocused]          = bg2;
 	colors[ImGuiCol_TabUnfocusedActive]    = bg3;
 	colors[ImGuiCol_TableHeaderBg]         = bg2;
 	colors[ImGuiCol_TableBorderStrong]     = bg1;
 	colors[ImGuiCol_TableBorderLight]      = ImVec4(bg1.x, bg1.y, bg1.z, 0.6f);
 	colors[ImGuiCol_TableRowBg]            = ImVec4(bg1.x, bg1.y, bg1.z, 0.2f);
 	colors[ImGuiCol_TableRowBgAlt]         = ImVec4(bg1.x, bg1.y, bg1.z, 0.35f);
 	colors[ImGuiCol_TextSelectedBg]        = ImVec4(accent.x, accent.y, accent.z, 0.30f);
 	colors[ImGuiCol_DragDropTarget]        = accent;
 	colors[ImGuiCol_NavHighlight]          = accent;
 	colors[ImGuiCol_NavWindowingHighlight] = ImVec4(ink.x, ink.y, ink.z, 0.70f);
 	colors[ImGuiCol_NavWindowingDimBg]     = ImVec4(0.0f, 0.0f, 0.0f, 0.45f);
 	colors[ImGuiCol_ModalWindowDimBg]      = ImVec4(0.0f, 0.0f, 0.0f, 0.45f);
 	colors[ImGuiCol_PlotLines]             = accent;
 	colors[ImGuiCol_PlotLinesHovered]      = ink;
 	colors[ImGuiCol_PlotHistogram]         = accent;
 	colors[ImGuiCol_PlotHistogramHovered]  = ink;
 }
--- a/themes/Gruvbox.h
+++ b/themes/Gruvbox.h
@@ -0,0 +1,204 @@
 // themes/Gruvbox.h — Gruvbox Dark/Light (medium) ImGui themes (header-only)
 #pragma once
 #include "ThemeHelpers.h"
 // Expects to be included from GUITheme.h after <imgui.h> and RGBA() helper
 static void
 ApplyGruvboxDarkMediumTheme()
 {
 	// Gruvbox (dark, medium) palette
 	const ImVec4 bg0 = RGBA(0x282828); // dark0
 	const ImVec4 bg1 = RGBA(0x3C3836); // dark1
 	const ImVec4 bg2 = RGBA(0x504945); // dark2
 	const ImVec4 bg3 = RGBA(0x665C54); // dark3
 	const ImVec4 fg1 = RGBA(0xEBDBB2); // light1
 	const ImVec4 fg0 = RGBA(0xFBF1C7); // light0
 	// accent colors
 	const ImVec4 yellow = RGBA(0xFABD2F);
 	const ImVec4 blue   = RGBA(0x83A598);
 	const ImVec4 aqua   = RGBA(0x8EC07C);
 	const ImVec4 orange = RGBA(0xFE8019);
 	ImGuiStyle &style      = ImGui::GetStyle();
 	style.WindowPadding    = ImVec2(8.0f, 8.0f);
 	style.FramePadding     = ImVec2(6.0f, 4.0f);
 	style.CellPadding      = ImVec2(6.0f, 4.0f);
 	style.ItemSpacing      = ImVec2(6.0f, 6.0f);
 	style.ItemInnerSpacing = ImVec2(6.0f, 4.0f);
 	style.ScrollbarSize    = 14.0f;
 	style.GrabMinSize      = 10.0f;
 	style.WindowRounding   = 4.0f;
 	style.FrameRounding    = 3.0f;
 	style.PopupRounding    = 4.0f;
 	style.GrabRounding     = 3.0f;
 	style.TabRounding      = 4.0f;
 	style.WindowBorderSize = 1.0f;
 	style.FrameBorderSize  = 1.0f;
 	ImVec4 *colors                = style.Colors;
 	colors[ImGuiCol_Text]         = fg1;
 	colors[ImGuiCol_TextDisabled] = ImVec4(fg1.x, fg1.y, fg1.z, 0.55f);
 	colors[ImGuiCol_WindowBg]     = bg0;
 	colors[ImGuiCol_ChildBg]      = bg0;
 	colors[ImGuiCol_PopupBg]      = ImVec4(bg1.x, bg1.y, bg1.z, 0.98f);
 	colors[ImGuiCol_Border]       = bg2;
 	colors[ImGuiCol_BorderShadow] = RGBA(0x000000, 0.0f);
 	colors[ImGuiCol_FrameBg]        = bg2;
 	colors[ImGuiCol_FrameBgHovered] = bg3;
 	colors[ImGuiCol_FrameBgActive]  = bg1;
 	colors[ImGuiCol_TitleBg]          = bg1;
 	colors[ImGuiCol_TitleBgActive]    = bg2;
 	colors[ImGuiCol_TitleBgCollapsed] = bg1;
 	colors[ImGuiCol_MenuBarBg]            = bg1;
 	colors[ImGuiCol_ScrollbarBg]          = bg0;
 	colors[ImGuiCol_ScrollbarGrab]        = bg3;
 	colors[ImGuiCol_ScrollbarGrabHovered] = bg2;
 	colors[ImGuiCol_ScrollbarGrabActive]  = bg1;
 	colors[ImGuiCol_CheckMark]        = aqua;
 	colors[ImGuiCol_SliderGrab]       = aqua;
 	colors[ImGuiCol_SliderGrabActive] = blue;
 	colors[ImGuiCol_Button]        = bg3;
 	colors[ImGuiCol_ButtonHovered] = bg2;
 	colors[ImGuiCol_ButtonActive]  = bg1;
 	colors[ImGuiCol_Header]        = bg3;
 	colors[ImGuiCol_HeaderHovered] = bg2;
 	colors[ImGuiCol_HeaderActive]  = bg2;
 	colors[ImGuiCol_Separator]        = bg2;
 	colors[ImGuiCol_SeparatorHovered] = bg1;
 	colors[ImGuiCol_SeparatorActive]  = blue;
 	colors[ImGuiCol_ResizeGrip]        = ImVec4(fg0.x, fg0.y, fg0.z, 0.12f);
 	colors[ImGuiCol_ResizeGripHovered] = ImVec4(aqua.x, aqua.y, aqua.z, 0.67f);
 	colors[ImGuiCol_ResizeGripActive]  = blue;
 	colors[ImGuiCol_Tab]                = bg2;
 	colors[ImGuiCol_TabHovered]         = bg1;
 	colors[ImGuiCol_TabActive]          = bg3;
 	colors[ImGuiCol_TabUnfocused]       = bg2;
 	colors[ImGuiCol_TabUnfocusedActive] = bg3;
 	colors[ImGuiCol_TableHeaderBg]     = bg2;
 	colors[ImGuiCol_TableBorderStrong] = bg1;
 	colors[ImGuiCol_TableBorderLight]  = ImVec4(bg1.x, bg1.y, bg1.z, 0.6f);
 	colors[ImGuiCol_TableRowBg]        = ImVec4(bg1.x, bg1.y, bg1.z, 0.2f);
 	colors[ImGuiCol_TableRowBgAlt]     = ImVec4(bg1.x, bg1.y, bg1.z, 0.35f);
 	colors[ImGuiCol_TextSelectedBg]        = ImVec4(orange.x, orange.y, orange.z, 0.30f);
 	colors[ImGuiCol_DragDropTarget]        = orange;
 	colors[ImGuiCol_NavHighlight]          = orange;
 	colors[ImGuiCol_NavWindowingHighlight] = ImVec4(fg0.x, fg0.y, fg0.z, 0.70f);
 	colors[ImGuiCol_NavWindowingDimBg]     = ImVec4(0.0f, 0.0f, 0.0f, 0.45f);
 	colors[ImGuiCol_ModalWindowDimBg]      = ImVec4(0.0f, 0.0f, 0.0f, 0.45f);
 	colors[ImGuiCol_PlotLines]             = aqua;
 	colors[ImGuiCol_PlotLinesHovered]      = blue;
 	colors[ImGuiCol_PlotHistogram]         = yellow;
 	colors[ImGuiCol_PlotHistogramHovered]  = orange;
 }
 static inline void
 ApplyGruvboxLightMediumTheme()
 {
 	// Gruvbox (light, medium) palette
 	const ImVec4 bg0 = RGBA(0xFBF1C7); // light0
 	const ImVec4 bg1 = RGBA(0xEBDBB2); // light1
 	const ImVec4 bg2 = RGBA(0xD5C4A1); // light2
 	const ImVec4 bg3 = RGBA(0xBDAE93); // light3
 	const ImVec4 fg1 = RGBA(0x3C3836); // dark1
 	const ImVec4 fg0 = RGBA(0x282828); // dark0
 	// accents
 	const ImVec4 yellow = RGBA(0xB57614);
 	const ImVec4 blue   = RGBA(0x076678);
 	const ImVec4 aqua   = RGBA(0x427B58);
 	const ImVec4 orange = RGBA(0xAF3A03);
 	ImGuiStyle &style      = ImGui::GetStyle();
 	style.WindowPadding    = ImVec2(8.0f, 8.0f);
 	style.FramePadding     = ImVec2(6.0f, 4.0f);
 	style.CellPadding      = ImVec2(6.0f, 4.0f);
 	style.ItemSpacing      = ImVec2(6.0f, 6.0f);
 	style.ItemInnerSpacing = ImVec2(6.0f, 4.0f);
 	style.ScrollbarSize    = 14.0f;
 	style.GrabMinSize      = 10.0f;
 	style.WindowRounding   = 4.0f;
 	style.FrameRounding    = 3.0f;
 	style.PopupRounding    = 4.0f;
 	style.GrabRounding     = 3.0f;
 	style.TabRounding      = 4.0f;
 	style.WindowBorderSize = 1.0f;
 	style.FrameBorderSize  = 1.0f;
 	ImVec4 *colors                = style.Colors;
 	colors[ImGuiCol_Text]         = fg1;
 	colors[ImGuiCol_TextDisabled] = ImVec4(fg1.x, fg1.y, fg1.z, 0.55f);
 	colors[ImGuiCol_WindowBg]     = bg0;
 	colors[ImGuiCol_ChildBg]      = bg0;
 	colors[ImGuiCol_PopupBg]      = ImVec4(bg1.x, bg1.y, bg1.z, 0.98f);
 	colors[ImGuiCol_Border]       = bg2;
 	colors[ImGuiCol_BorderShadow] = RGBA(0x000000, 0.0f);
 	colors[ImGuiCol_FrameBg]        = bg2;
 	colors[ImGuiCol_FrameBgHovered] = bg3;
 	colors[ImGuiCol_FrameBgActive]  = bg1;
 	colors[ImGuiCol_TitleBg]          = bg1;
 	colors[ImGuiCol_TitleBgActive]    = bg2;
 	colors[ImGuiCol_TitleBgCollapsed] = bg1;
 	colors[ImGuiCol_MenuBarBg]            = bg1;
 	colors[ImGuiCol_ScrollbarBg]          = bg0;
 	colors[ImGuiCol_ScrollbarGrab]        = bg3;
 	colors[ImGuiCol_ScrollbarGrabHovered] = bg2;
 	colors[ImGuiCol_ScrollbarGrabActive]  = bg1;
 	colors[ImGuiCol_CheckMark]        = aqua;
 	colors[ImGuiCol_SliderGrab]       = aqua;
 	colors[ImGuiCol_SliderGrabActive] = blue;
 	colors[ImGuiCol_Button]        = bg3;
 	colors[ImGuiCol_ButtonHovered] = bg2;
 	colors[ImGuiCol_ButtonActive]  = bg1;
 	colors[ImGuiCol_Header]        = bg3;
 	colors[ImGuiCol_HeaderHovered] = bg2;
 	colors[ImGuiCol_HeaderActive]  = bg2;
 	colors[ImGuiCol_Separator]        = bg2;
 	colors[ImGuiCol_SeparatorHovered] = bg1;
 	colors[ImGuiCol_SeparatorActive]  = blue;
 	colors[ImGuiCol_ResizeGrip]        = ImVec4(fg0.x, fg0.y, fg0.z, 0.12f);
 	colors[ImGuiCol_ResizeGripHovered] = ImVec4(aqua.x, aqua.y, aqua.z, 0.67f);
 	colors[ImGuiCol_ResizeGripActive]  = blue;
 	colors[ImGuiCol_Tab]                = bg2;
 	colors[ImGuiCol_TabHovered]         = bg1;
 	colors[ImGuiCol_TabActive]          = bg3;
 	colors[ImGuiCol_TabUnfocused]       = bg2;
 	colors[ImGuiCol_TabUnfocusedActive] = bg3;
 	colors[ImGuiCol_TableHeaderBg]     = bg2;
 	colors[ImGuiCol_TableBorderStrong] = bg1;
 	colors[ImGuiCol_TableBorderLight]  = ImVec4(bg1.x, bg1.y, bg1.z, 0.6f);
 	colors[ImGuiCol_TableRowBg]        = ImVec4(bg1.x, bg1.y, bg1.z, 0.2f);
 	colors[ImGuiCol_TableRowBgAlt]     = ImVec4(bg1.x, bg1.y, bg1.z, 0.35f);
 	colors[ImGuiCol_TextSelectedBg]        = ImVec4(orange.x, orange.y, orange.z, 0.30f);
 	colors[ImGuiCol_DragDropTarget]        = orange;
 	colors[ImGuiCol_NavHighlight]          = orange;
 	colors[ImGuiCol_NavWindowingHighlight] = ImVec4(fg0.x, fg0.y, fg0.z, 0.70f);
 	colors[ImGuiCol_NavWindowingDimBg]     = ImVec4(0.0f, 0.0f, 0.0f, 0.45f);
 	colors[ImGuiCol_ModalWindowDimBg]      = ImVec4(0.0f, 0.0f, 0.0f, 0.45f);
 	colors[ImGuiCol_PlotLines]             = aqua;
 	colors[ImGuiCol_PlotLinesHovered]      = blue;
 	colors[ImGuiCol_PlotHistogram]         = yellow;
 	colors[ImGuiCol_PlotHistogramHovered]  = orange;
 }
--- a/themes/Nord.h
+++ b/themes/Nord.h
@@ -0,0 +1,111 @@
 // themes/Nord.h — Nord-inspired ImGui theme (header-only)
 #pragma once
 #include "ThemeHelpers.h"
 // Expects to be included from GUITheme.h after <imgui.h> and RGBA() helper
 static void
 ApplyNordImGuiTheme()
 {
 	// Nord palette
 	const ImVec4 nord0  = RGBA(0x2E3440); // darkest bg
 	const ImVec4 nord1  = RGBA(0x3B4252);
 	const ImVec4 nord2  = RGBA(0x434C5E);
 	const ImVec4 nord3  = RGBA(0x4C566A);
 	const ImVec4 nord4  = RGBA(0xD8DEE9);
 	const ImVec4 nord6  = RGBA(0xECEFF4); // lightest
 	const ImVec4 nord8  = RGBA(0x88C0D0); // cyan
 	const ImVec4 nord9  = RGBA(0x81A1C1); // blue
 	const ImVec4 nord10 = RGBA(0x5E81AC); // blue dark
 	const ImVec4 nord12 = RGBA(0xD08770); // orange
 	const ImVec4 nord13 = RGBA(0xEBCB8B); // yellow
 	ImGuiStyle &style = ImGui::GetStyle();
 	// Base style tweaks to suit Nord aesthetics
 	style.WindowPadding    = ImVec2(8.0f, 8.0f);
 	style.FramePadding     = ImVec2(6.0f, 4.0f);
 	style.CellPadding      = ImVec2(6.0f, 4.0f);
 	style.ItemSpacing      = ImVec2(6.0f, 6.0f);
 	style.ItemInnerSpacing = ImVec2(6.0f, 4.0f);
 	style.ScrollbarSize    = 14.0f;
 	style.GrabMinSize      = 10.0f;
 	style.WindowRounding   = 4.0f;
 	style.FrameRounding    = 3.0f;
 	style.PopupRounding    = 4.0f;
 	style.GrabRounding     = 3.0f;
 	style.TabRounding      = 4.0f;
 	style.WindowBorderSize = 1.0f;
 	style.FrameBorderSize  = 1.0f;
 	ImVec4 *colors = style.Colors;
 	colors[ImGuiCol_Text]         = nord4; // primary text
 	colors[ImGuiCol_TextDisabled] = ImVec4(nord4.x, nord4.y, nord4.z, 0.55f);
 	colors[ImGuiCol_WindowBg]     = nord0;
 	colors[ImGuiCol_ChildBg]      = nord0;
 	colors[ImGuiCol_PopupBg]      = ImVec4(nord1.x, nord1.y, nord1.z, 0.98f);
 	colors[ImGuiCol_Border]       = nord2;
 	colors[ImGuiCol_BorderShadow] = RGBA(0x000000, 0.0f);
 	colors[ImGuiCol_FrameBg]        = nord2;
 	colors[ImGuiCol_FrameBgHovered] = nord3;
 	colors[ImGuiCol_FrameBgActive]  = nord1;
 	colors[ImGuiCol_TitleBg]          = nord1;
 	colors[ImGuiCol_TitleBgActive]    = nord2;
 	colors[ImGuiCol_TitleBgCollapsed] = nord1;
 	colors[ImGuiCol_MenuBarBg]            = nord1;
 	colors[ImGuiCol_ScrollbarBg]          = nord10;
 	colors[ImGuiCol_ScrollbarGrab]        = nord3;
 	colors[ImGuiCol_ScrollbarGrabHovered] = nord2;
 	colors[ImGuiCol_ScrollbarGrabActive]  = nord1;
 	colors[ImGuiCol_CheckMark]        = nord8;
 	colors[ImGuiCol_SliderGrab]       = nord8;
 	colors[ImGuiCol_SliderGrabActive] = nord9;
 	colors[ImGuiCol_Button]        = nord3;
 	colors[ImGuiCol_ButtonHovered] = nord2;
 	colors[ImGuiCol_ButtonActive]  = nord1;
 	colors[ImGuiCol_Header]        = nord3;
 	colors[ImGuiCol_HeaderHovered] = nord10;
 	colors[ImGuiCol_HeaderActive]  = nord10;
 	colors[ImGuiCol_Separator]        = nord2;
 	colors[ImGuiCol_SeparatorHovered] = nord10;
 	colors[ImGuiCol_SeparatorActive]  = nord9;
 	colors[ImGuiCol_ResizeGrip]        = ImVec4(nord6.x, nord6.y, nord6.z, 0.12f);
 	colors[ImGuiCol_ResizeGripHovered] = ImVec4(nord8.x, nord8.y, nord8.z, 0.67f);
 	colors[ImGuiCol_ResizeGripActive]  = nord9;
 	colors[ImGuiCol_Tab]                = nord2;
 	colors[ImGuiCol_TabHovered]         = nord10;
 	colors[ImGuiCol_TabActive]          = nord3;
 	colors[ImGuiCol_TabUnfocused]       = nord2;
 	colors[ImGuiCol_TabUnfocusedActive] = nord3;
 	// Docking colors omitted for compatibility
 	colors[ImGuiCol_TableHeaderBg]     = nord2;
 	colors[ImGuiCol_TableBorderStrong] = nord1;
 	colors[ImGuiCol_TableBorderLight]  = ImVec4(nord1.x, nord1.y, nord1.z, 0.6f);
 	colors[ImGuiCol_TableRowBg]        = ImVec4(nord1.x, nord1.y, nord1.z, 0.2f);
 	colors[ImGuiCol_TableRowBgAlt]     = ImVec4(nord1.x, nord1.y, nord1.z, 0.35f);
 	colors[ImGuiCol_TextSelectedBg]        = ImVec4(nord8.x, nord8.y, nord8.z, 0.35f);
 	colors[ImGuiCol_DragDropTarget]        = nord13;
 	colors[ImGuiCol_NavHighlight]          = nord9;
 	colors[ImGuiCol_NavWindowingHighlight] = ImVec4(nord6.x, nord6.y, nord6.z, 0.7f);
 	colors[ImGuiCol_NavWindowingDimBg]     = ImVec4(nord0.x, nord0.y, nord0.z, 0.6f);
 	colors[ImGuiCol_ModalWindowDimBg]      = ImVec4(nord0.x, nord0.y, nord0.z, 0.6f);
 	// Plots
 	colors[ImGuiCol_PlotLines]            = nord8;
 	colors[ImGuiCol_PlotLinesHovered]     = nord9;
 	colors[ImGuiCol_PlotHistogram]        = nord13;
 	colors[ImGuiCol_PlotHistogramHovered] = nord12;
 }
--- a/themes/Plan9.h
+++ b/themes/Plan9.h
@@ -0,0 +1,89 @@
 // themes/Plan9.h — Plan 9 acme-inspired ImGui theme (header-only)
 #pragma once
 #include "ThemeHelpers.h"
 // Expects to be included from GUITheme.h after <imgui.h> and RGBA() helper
 static void
 ApplyPlan9Theme()
 {
 	// Acme-like colors
 	const ImVec4 paper  = RGBA(0xFFFFE8); // pale yellow paper
 	const ImVec4 pane   = RGBA(0xFFF4C1); // slightly deeper for frames
 	const ImVec4 ink    = RGBA(0x000000); // black text
 	constexpr auto dim  = ImVec4(0, 0, 0, 0.60f);
 	const ImVec4 border = RGBA(0x000000); // 1px black
 	const ImVec4 blue   = RGBA(0x0064FF); // acme-ish blue accents
 	const ImVec4 blueH  = RGBA(0x4C8DFF); // hover/active
 	ImGuiStyle &style      = ImGui::GetStyle();
 	style.WindowPadding    = ImVec2(6.0f, 6.0f);
 	style.FramePadding     = ImVec2(5.0f, 3.0f);
 	style.CellPadding      = ImVec2(5.0f, 3.0f);
 	style.ItemSpacing      = ImVec2(6.0f, 6.0f);
 	style.ItemInnerSpacing = ImVec2(6.0f, 4.0f);
 	style.ScrollbarSize    = 14.0f;
 	style.GrabMinSize      = 10.0f;
 	style.WindowRounding   = 0.0f;
 	style.FrameRounding    = 0.0f;
 	style.PopupRounding    = 0.0f;
 	style.GrabRounding     = 0.0f;
 	style.TabRounding      = 0.0f;
 	style.WindowBorderSize = 1.0f;
 	style.FrameBorderSize  = 1.0f;
 	ImVec4 *c                         = style.Colors;
 	c[ImGuiCol_Text]                  = ink;
 	c[ImGuiCol_TextDisabled]          = dim;
 	c[ImGuiCol_WindowBg]              = paper;
 	c[ImGuiCol_ChildBg]               = paper;
 	c[ImGuiCol_PopupBg]               = ImVec4(pane.x, pane.y, pane.z, 0.98f);
 	c[ImGuiCol_Border]                = border;
 	c[ImGuiCol_BorderShadow]          = RGBA(0x000000, 0.0f);
 	c[ImGuiCol_FrameBg]               = pane;
 	c[ImGuiCol_FrameBgHovered]        = RGBA(0xFFEBA0);
 	c[ImGuiCol_FrameBgActive]         = RGBA(0xFFE387);
 	c[ImGuiCol_TitleBg]               = pane;
 	c[ImGuiCol_TitleBgActive]         = RGBA(0xFFE8A6);
 	c[ImGuiCol_TitleBgCollapsed]      = pane;
 	c[ImGuiCol_MenuBarBg]             = pane;
 	c[ImGuiCol_ScrollbarBg]           = paper;
 	c[ImGuiCol_ScrollbarGrab]         = RGBA(0xEADFA5);
 	c[ImGuiCol_ScrollbarGrabHovered]  = RGBA(0xE2D37F);
 	c[ImGuiCol_ScrollbarGrabActive]   = RGBA(0xD8C757);
 	c[ImGuiCol_CheckMark]             = blue;
 	c[ImGuiCol_SliderGrab]            = blue;
 	c[ImGuiCol_SliderGrabActive]      = blueH;
 	c[ImGuiCol_Button]                = RGBA(0xFFF1B0);
 	c[ImGuiCol_ButtonHovered]         = RGBA(0xFFE892);
 	c[ImGuiCol_ButtonActive]          = RGBA(0xFFE072);
 	c[ImGuiCol_Header]                = RGBA(0xFFF1B0);
 	c[ImGuiCol_HeaderHovered]         = RGBA(0xFFE892);
 	c[ImGuiCol_HeaderActive]          = RGBA(0xFFE072);
 	c[ImGuiCol_Separator]             = border;
 	c[ImGuiCol_SeparatorHovered]      = blue;
 	c[ImGuiCol_SeparatorActive]       = blueH;
 	c[ImGuiCol_ResizeGrip]            = ImVec4(0, 0, 0, 0.12f);
 	c[ImGuiCol_ResizeGripHovered]     = ImVec4(blue.x, blue.y, blue.z, 0.67f);
 	c[ImGuiCol_ResizeGripActive]      = blueH;
 	c[ImGuiCol_Tab]                   = RGBA(0xFFE8A6);
 	c[ImGuiCol_TabHovered]            = RGBA(0xFFE072);
 	c[ImGuiCol_TabActive]             = RGBA(0xFFD859);
 	c[ImGuiCol_TabUnfocused]          = RGBA(0xFFE8A6);
 	c[ImGuiCol_TabUnfocusedActive]    = RGBA(0xFFD859);
 	c[ImGuiCol_TableHeaderBg]         = RGBA(0xFFE8A6);
 	c[ImGuiCol_TableBorderStrong]     = border;
 	c[ImGuiCol_TableBorderLight]      = ImVec4(0, 0, 0, 0.35f);
 	c[ImGuiCol_TableRowBg]            = ImVec4(0, 0, 0, 0.04f);
 	c[ImGuiCol_TableRowBgAlt]         = ImVec4(0, 0, 0, 0.08f);
 	c[ImGuiCol_TextSelectedBg]        = ImVec4(blueH.x, blueH.y, blueH.z, 0.35f);
 	c[ImGuiCol_DragDropTarget]        = blue;
 	c[ImGuiCol_NavHighlight]          = blue;
 	c[ImGuiCol_NavWindowingHighlight] = ImVec4(0, 0, 0, 0.20f);
 	c[ImGuiCol_NavWindowingDimBg]     = ImVec4(0, 0, 0, 0.20f);
 	c[ImGuiCol_ModalWindowDimBg]      = ImVec4(0, 0, 0, 0.20f);
 	c[ImGuiCol_PlotLines]             = blue;
 	c[ImGuiCol_PlotLinesHovered]      = blueH;
 	c[ImGuiCol_PlotHistogram]         = blue;
 	c[ImGuiCol_PlotHistogramHovered]  = blueH;
 }
--- a/themes/Solarized.h
+++ b/themes/Solarized.h
@@ -0,0 +1,184 @@
 // themes/Solarized.h — Solarized Dark/Light ImGui themes (header-only)
 #pragma once
 #include "ThemeHelpers.h"
 // Expects to be included from GUITheme.h after <imgui.h> and RGBA() helper
 static void
 ApplySolarizedDarkTheme()
 {
 	// Base colors from Ethan Schoonover Solarized
 	const ImVec4 base03 = RGBA(0x002b36);
 	const ImVec4 base02 = RGBA(0x073642);
 	const ImVec4 base01 = RGBA(0x586e75);
 	const ImVec4 base00 = RGBA(0x657b83);
 	const ImVec4 base0  = RGBA(0x839496);
 	const ImVec4 base1  = RGBA(0x93a1a1);
 	const ImVec4 base2  = RGBA(0xeee8d5);
 	const ImVec4 yellow = RGBA(0xb58900);
 	const ImVec4 orange = RGBA(0xcb4b16);
 	const ImVec4 blue   = RGBA(0x268bd2);
 	const ImVec4 cyan   = RGBA(0x2aa198);
 	ImGuiStyle &style      = ImGui::GetStyle();
 	style.WindowPadding    = ImVec2(8.0f, 8.0f);
 	style.FramePadding     = ImVec2(6.0f, 4.0f);
 	style.CellPadding      = ImVec2(6.0f, 4.0f);
 	style.ItemSpacing      = ImVec2(6.0f, 6.0f);
 	style.ItemInnerSpacing = ImVec2(6.0f, 4.0f);
 	style.ScrollbarSize    = 14.0f;
 	style.GrabMinSize      = 10.0f;
 	style.WindowRounding   = 3.0f;
 	style.FrameRounding    = 3.0f;
 	style.PopupRounding    = 3.0f;
 	style.GrabRounding     = 3.0f;
 	style.TabRounding      = 3.0f;
 	style.WindowBorderSize = 1.0f;
 	style.FrameBorderSize  = 1.0f;
 	ImVec4 *c                         = style.Colors;
 	c[ImGuiCol_Text]                  = base0;
 	c[ImGuiCol_TextDisabled]          = ImVec4(base01.x, base01.y, base01.z, 1.0f);
 	c[ImGuiCol_WindowBg]              = base03;
 	c[ImGuiCol_ChildBg]               = base03;
 	c[ImGuiCol_PopupBg]               = ImVec4(base02.x, base02.y, base02.z, 0.98f);
 	c[ImGuiCol_Border]                = base02;
 	c[ImGuiCol_BorderShadow]          = RGBA(0x000000, 0.0f);
 	c[ImGuiCol_FrameBg]               = base02;
 	c[ImGuiCol_FrameBgHovered]        = base01;
 	c[ImGuiCol_FrameBgActive]         = base00;
 	c[ImGuiCol_TitleBg]               = base02;
 	c[ImGuiCol_TitleBgActive]         = base01;
 	c[ImGuiCol_TitleBgCollapsed]      = base02;
 	c[ImGuiCol_MenuBarBg]             = base02;
 	c[ImGuiCol_ScrollbarBg]           = base02;
 	c[ImGuiCol_ScrollbarGrab]         = base01;
 	c[ImGuiCol_ScrollbarGrabHovered]  = base00;
 	c[ImGuiCol_ScrollbarGrabActive]   = blue;
 	c[ImGuiCol_CheckMark]             = cyan;
 	c[ImGuiCol_SliderGrab]            = cyan;
 	c[ImGuiCol_SliderGrabActive]      = blue;
 	c[ImGuiCol_Button]                = base01;
 	c[ImGuiCol_ButtonHovered]         = base00;
 	c[ImGuiCol_ButtonActive]          = blue;
 	c[ImGuiCol_Header]                = base01;
 	c[ImGuiCol_HeaderHovered]         = base00;
 	c[ImGuiCol_HeaderActive]          = base00;
 	c[ImGuiCol_Separator]             = base01;
 	c[ImGuiCol_SeparatorHovered]      = base00;
 	c[ImGuiCol_SeparatorActive]       = blue;
 	c[ImGuiCol_ResizeGrip]            = ImVec4(base1.x, base1.y, base1.z, 0.12f);
 	c[ImGuiCol_ResizeGripHovered]     = ImVec4(cyan.x, cyan.y, cyan.z, 0.67f);
 	c[ImGuiCol_ResizeGripActive]      = blue;
 	c[ImGuiCol_Tab]                   = base01;
 	c[ImGuiCol_TabHovered]            = base00;
 	c[ImGuiCol_TabActive]             = base02;
 	c[ImGuiCol_TabUnfocused]          = base01;
 	c[ImGuiCol_TabUnfocusedActive]    = base02;
 	c[ImGuiCol_TableHeaderBg]         = base01;
 	c[ImGuiCol_TableBorderStrong]     = base00;
 	c[ImGuiCol_TableBorderLight]      = ImVec4(base00.x, base00.y, base00.z, 0.6f);
 	c[ImGuiCol_TableRowBg]            = ImVec4(base02.x, base02.y, base02.z, 0.2f);
 	c[ImGuiCol_TableRowBgAlt]         = ImVec4(base02.x, base02.y, base02.z, 0.35f);
 	c[ImGuiCol_TextSelectedBg]        = ImVec4(cyan.x, cyan.y, cyan.z, 0.30f);
 	c[ImGuiCol_DragDropTarget]        = yellow;
 	c[ImGuiCol_NavHighlight]          = blue;
 	c[ImGuiCol_NavWindowingHighlight] = ImVec4(base2.x, base2.y, base2.z, 0.70f);
 	c[ImGuiCol_NavWindowingDimBg]     = ImVec4(base03.x, base03.y, base03.z, 0.60f);
 	c[ImGuiCol_ModalWindowDimBg]      = ImVec4(base03.x, base03.y, base03.z, 0.60f);
 	c[ImGuiCol_PlotLines]             = cyan;
 	c[ImGuiCol_PlotLinesHovered]      = blue;
 	c[ImGuiCol_PlotHistogram]         = yellow;
 	c[ImGuiCol_PlotHistogramHovered]  = orange;
 }
 static inline void
 ApplySolarizedLightTheme()
 {
 	// Base colors from Ethan Schoonover Solarized (light variant)
 	const ImVec4 base3  = RGBA(0xfdf6e3);
 	const ImVec4 base2  = RGBA(0xeee8d5);
 	const ImVec4 base1  = RGBA(0x93a1a1);
 	const ImVec4 base0  = RGBA(0x839496);
 	const ImVec4 base00 = RGBA(0x657b83);
 	const ImVec4 base01 = RGBA(0x586e75);
 	const ImVec4 base02 = RGBA(0x073642);
 	const ImVec4 base03 = RGBA(0x002b36);
 	const ImVec4 yellow = RGBA(0xb58900);
 	const ImVec4 orange = RGBA(0xcb4b16);
 	const ImVec4 blue   = RGBA(0x268bd2);
 	const ImVec4 cyan   = RGBA(0x2aa198);
 	ImGuiStyle &style      = ImGui::GetStyle();
 	style.WindowPadding    = ImVec2(8.0f, 8.0f);
 	style.FramePadding     = ImVec2(6.0f, 4.0f);
 	style.CellPadding      = ImVec2(6.0f, 4.0f);
 	style.ItemSpacing      = ImVec2(6.0f, 6.0f);
 	style.ItemInnerSpacing = ImVec2(6.0f, 4.0f);
 	style.ScrollbarSize    = 14.0f;
 	style.GrabMinSize      = 10.0f;
 	style.WindowRounding   = 3.0f;
 	style.FrameRounding    = 3.0f;
 	style.PopupRounding    = 3.0f;
 	style.GrabRounding     = 3.0f;
 	style.TabRounding      = 3.0f;
 	style.WindowBorderSize = 1.0f;
 	style.FrameBorderSize  = 1.0f;
 	ImVec4 *c                         = style.Colors;
 	c[ImGuiCol_Text]                  = base00;
 	c[ImGuiCol_TextDisabled]          = ImVec4(base01.x, base01.y, base01.z, 1.0f);
 	c[ImGuiCol_WindowBg]              = base3;
 	c[ImGuiCol_ChildBg]               = base3;
 	c[ImGuiCol_PopupBg]               = ImVec4(base2.x, base2.y, base2.z, 0.98f);
 	c[ImGuiCol_Border]                = base1;
 	c[ImGuiCol_BorderShadow]          = RGBA(0x000000, 0.0f);
 	c[ImGuiCol_FrameBg]               = base2;
 	c[ImGuiCol_FrameBgHovered]        = base1;
 	c[ImGuiCol_FrameBgActive]         = base0;
 	c[ImGuiCol_TitleBg]               = base2;
 	c[ImGuiCol_TitleBgActive]         = base1;
 	c[ImGuiCol_TitleBgCollapsed]      = base2;
 	c[ImGuiCol_MenuBarBg]             = base2;
 	c[ImGuiCol_ScrollbarBg]           = base2;
 	c[ImGuiCol_ScrollbarGrab]         = base1;
 	c[ImGuiCol_ScrollbarGrabHovered]  = base0;
 	c[ImGuiCol_ScrollbarGrabActive]   = blue;
 	c[ImGuiCol_CheckMark]             = cyan;
 	c[ImGuiCol_SliderGrab]            = cyan;
 	c[ImGuiCol_SliderGrabActive]      = blue;
 	c[ImGuiCol_Button]                = base1;
 	c[ImGuiCol_ButtonHovered]         = base0;
 	c[ImGuiCol_ButtonActive]          = blue;
 	c[ImGuiCol_Header]                = base1;
 	c[ImGuiCol_HeaderHovered]         = base0;
 	c[ImGuiCol_HeaderActive]          = base0;
 	c[ImGuiCol_Separator]             = base1;
 	c[ImGuiCol_SeparatorHovered]      = base0;
 	c[ImGuiCol_SeparatorActive]       = blue;
 	c[ImGuiCol_ResizeGrip]            = ImVec4(base1.x, base1.y, base1.z, 0.12f);
 	c[ImGuiCol_ResizeGripHovered]     = ImVec4(cyan.x, cyan.y, cyan.z, 0.67f);
 	c[ImGuiCol_ResizeGripActive]      = blue;
 	c[ImGuiCol_Tab]                   = base1;
 	c[ImGuiCol_TabHovered]            = base0;
 	c[ImGuiCol_TabActive]             = base2;
 	c[ImGuiCol_TabUnfocused]          = base1;
 	c[ImGuiCol_TabUnfocusedActive]    = base2;
 	c[ImGuiCol_TableHeaderBg]         = base1;
 	c[ImGuiCol_TableBorderStrong]     = base0;
 	c[ImGuiCol_TableBorderLight]      = ImVec4(base0.x, base0.y, base0.z, 0.6f);
 	c[ImGuiCol_TableRowBg]            = ImVec4(base02.x, base02.y, base02.z, 0.2f);
 	c[ImGuiCol_TableRowBgAlt]         = ImVec4(base02.x, base02.y, base02.z, 0.35f);
 	c[ImGuiCol_TextSelectedBg]        = ImVec4(cyan.x, cyan.y, cyan.z, 0.30f);
 	c[ImGuiCol_DragDropTarget]        = yellow;
 	c[ImGuiCol_NavHighlight]          = blue;
 	c[ImGuiCol_NavWindowingHighlight] = ImVec4(base2.x, base2.y, base2.z, 0.70f);
 	c[ImGuiCol_NavWindowingDimBg]     = ImVec4(base03.x, base03.y, base03.z, 0.60f);
 	c[ImGuiCol_ModalWindowDimBg]      = ImVec4(base03.x, base03.y, base03.z, 0.60f);
 	c[ImGuiCol_PlotLines]             = cyan;
 	c[ImGuiCol_PlotLinesHovered]      = blue;
 	c[ImGuiCol_PlotHistogram]         = yellow;
 	c[ImGuiCol_PlotHistogramHovered]  = orange;
 }
--- a/themes/ThemeHelpers.h
+++ b/themes/ThemeHelpers.h
@@ -0,0 +1,17 @@
 #ifndef KTE_THEMEHELPERS_H
 #define KTE_THEMEHELPERS_H
 #include "imgui.h"
 // Small helper to convert packed RGB (0xRRGGBB) + optional alpha to ImVec4
 static ImVec4
 RGBA(const unsigned int rgb, float a = 1.0f)
 {
 	const float r = static_cast<float>(rgb >> 16 & 0xFF) / 255.0f;
 	const float g = static_cast<float>(rgb >> 8 & 0xFF) / 255.0f;
 	const float b = static_cast<float>(rgb & 0xFF) / 255.0f;
 	return {r, g, b, a};
 }
 #endif //KTE_THEMEHELPERS_H
Author	SHA1	Message	Date
Kyle Isom	0bfe75fbf0	Refactor indentation for consistent style across codebase. Some checks failed Release / Bump Homebrew formula (push) Has been cancelled Release / Build Linux amd64 (push) Has been cancelled Release / Build Linux arm64 (push) Has been cancelled Release / Build macOS arm64 (.app) (push) Has been cancelled Release / Create GitHub Release (push) Has been cancelled	2025-12-02 01:37:44 -08:00
Kyle Isom	d15b241140	Refactor syntax highlighting infrastructure and related classes. - Moved all language highlighter implementations (`CppHighlighter`, `GoHighlighter`, `JsonHighlighter`, etc.), the engine, and registry to `syntax/`.	2025-12-02 01:36:26 -08:00
Kyle Isom	ceef6af3ae	Add extensible highlighter registration and Tree-sitter support. Some checks failed Release / Bump Homebrew formula (push) Has been cancelled Release / Build Linux amd64 (push) Has been cancelled Release / Build Linux arm64 (push) Has been cancelled Release / Build macOS arm64 (.app) (push) Has been cancelled Release / Create GitHub Release (push) Has been cancelled - Implemented runtime API for registering custom highlighters. - Added optional Tree-sitter integration for advanced syntax parsing (disabled by default). - Updated buffer initialization and copying to support dynamic highlighter configuration. - Introduced `NullHighlighter` as a fallback for unsupported filetypes. - Enhanced CMake configuration with `KTE_ENABLE_TREESITTER` option.	2025-12-01 19:04:37 -08:00
Kyle Isom	e62cf3ee28	Add viewport-aware syntax prefetching and background warming. - Added prefetching in both terminal and GUI renderers to optimize visible row highlights. - Introduced background worker for offscreen highlight warming to improve scrolling performance. - Refactored `HighlighterEngine` to manage thread-safety, caching, and stateful re-computation. - Integrated changes into `HighlighterEngine`, `TerminalRenderer`, and `GUIRenderer`. - Bumped version to 1.2.0 in preparation for the release.	2025-12-01 18:37:01 -08:00
Kyle Isom	1a77f28ce4	Add syntax highlighting infrastructure - Introduced `HighlighterRegistry` with support for multiple language highlighters (e.g., JSON, Markdown, Python). - Added `JsonHighlighter` implementation for basic JSON syntax highlighting.	2025-12-01 18:20:36 -08:00
Kyle Isom	4d84b352eb	format style	2025-12-01 16:47:16 -08:00
Kyle Isom	1892075d82	bump version Some checks failed Release / Bump Homebrew formula (push) Has been cancelled Release / Build Linux amd64 (push) Has been cancelled Release / Build Linux arm64 (push) Has been cancelled Release / Build macOS arm64 (.app) (push) Has been cancelled Release / Create GitHub Release (push) Has been cancelled	2025-12-01 16:38:10 -08:00
Kyle Isom	719862c842	Fix double scroll issue.	2025-12-01 16:37:51 -08:00
Kyle Isom	655cc40162	Refine help text, keybindings, GUI themes, and undo system. Some checks failed Release / Bump Homebrew formula (push) Has been cancelled Release / Build Linux amd64 (push) Has been cancelled Release / Build Linux arm64 (push) Has been cancelled Release / Build macOS arm64 (.app) (push) Has been cancelled Release / Create GitHub Release (push) Has been cancelled - Expanded help text and command documentation with detailed keybinding descriptions. - Added theme customization support to GUIConfig (Nord default, light/dark variants). - Adjusted for consistent indentation and debug instrumentation in undo system. - Enhanced test cases for multi-line, UTF-8, and branching scenarios.	2025-12-01 15:21:52 -08:00