bump version

.gitignore

@@ -1,3 +1,5 @@
 !.idea
 cmake-build*
 build
+/imgui.ini
+result

.idea/workspace.xml

@@ -33,10 +33,20 @@
     </configurations>
   </component>
   <component name="ChangeListManager">
-    <list default="true" id="e1fe3ab0-3650-4fca-8664-a247d5dfa457" name="Changes" comment="Actually add the screenshot.">
+    <list default="true" id="e1fe3ab0-3650-4fca-8664-a247d5dfa457" name="Changes" comment="add regex and search/replace functionality to editor">
+      <change afterPath="$PROJECT_DIR$/HelpText.cc" afterDir="false" />
+      <change afterPath="$PROJECT_DIR$/HelpText.h" afterDir="false" />
       <change beforePath="$PROJECT_DIR$/.idea/workspace.xml" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/workspace.xml" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/Buffer.cc" beforeDir="false" afterPath="$PROJECT_DIR$/Buffer.cc" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/Buffer.h" beforeDir="false" afterPath="$PROJECT_DIR$/Buffer.h" afterDir="false" />
       <change beforePath="$PROJECT_DIR$/CMakeLists.txt" beforeDir="false" afterPath="$PROJECT_DIR$/CMakeLists.txt" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/Command.cc" beforeDir="false" afterPath="$PROJECT_DIR$/Command.cc" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/Command.h" beforeDir="false" afterPath="$PROJECT_DIR$/Command.h" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/Editor.h" beforeDir="false" afterPath="$PROJECT_DIR$/Editor.h" afterDir="false" />
       <change beforePath="$PROJECT_DIR$/GUIRenderer.cc" beforeDir="false" afterPath="$PROJECT_DIR$/GUIRenderer.cc" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/KKeymap.cc" beforeDir="false" afterPath="$PROJECT_DIR$/KKeymap.cc" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/ROADMAP.md" beforeDir="false" afterPath="$PROJECT_DIR$/ROADMAP.md" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/TerminalRenderer.cc" beforeDir="false" afterPath="$PROJECT_DIR$/TerminalRenderer.cc" afterDir="false" />
     </list>
     <option name="SHOW_DIALOG" value="false" />
     <option name="HIGHLIGHT_CONFLICTS" value="true" />
@@ -63,10 +73,14 @@
   <component name="HighlightingSettingsPerFile">
     <setting file="mock:///AIAssistantSnippet.." root0="SKIP_HIGHLIGHTING" />
     <setting file="mock:///AIAssistantSnippet.." root0="SKIP_HIGHLIGHTING" />
+    <setting file="mock:///AIAssistantSnippet.." root0="SKIP_HIGHLIGHTING" />
   </component>
   <component name="OptimizeOnSaveOptions">
     <option name="myRunOnSave" value="true" />
   </component>
+  <component name="ProblemsViewState">
+    <option name="selectedTabId" value="AISelfReview" />
+  </component>
   <component name="ProjectApplicationVersion">
     <option name="ide" value="CLion" />
     <option name="majorVersion" value="2025" />
@@ -139,7 +153,7 @@
         <option name="com.jetbrains.cidr.execution.CidrBuildBeforeRunTaskProvider$BuildBeforeRunTask" enabled="true" />
       </method>
     </configuration>
-    <configuration name="kge" type="CMakeRunConfiguration" factoryName="Application" REDIRECT_INPUT="false" ELEVATE="false" USE_EXTERNAL_CONSOLE="false" EMULATE_TERMINAL="false" WORKING_DIR="file://$PROJECT_DIR$" PASS_PARENT_ENVS_2="true" PROJECT_NAME="kte" TARGET_NAME="kge" CONFIG_NAME="Debug" RUN_TARGET_PROJECT_NAME="kte" RUN_TARGET_NAME="kge">
+    <configuration name="kge" type="CMakeRunConfiguration" factoryName="Application" PROGRAM_PARAMS="$PROJECT_DIR$/cmake-build-debug/test.txt" REDIRECT_INPUT="false" ELEVATE="false" USE_EXTERNAL_CONSOLE="false" EMULATE_TERMINAL="false" WORKING_DIR="file://$PROJECT_DIR$" PASS_PARENT_ENVS_2="true" PROJECT_NAME="kte" TARGET_NAME="kge" CONFIG_NAME="Debug" RUN_TARGET_PROJECT_NAME="kte" RUN_TARGET_NAME="kge">
       <method v="2">
         <option name="com.jetbrains.cidr.execution.CidrBuildBeforeRunTaskProvider$BuildBeforeRunTask" enabled="true" />
       </method>
@@ -170,7 +184,7 @@
       <workItem from="1764539556448" duration="156000" />
       <workItem from="1764539725338" duration="1075000" />
       <workItem from="1764542392763" duration="3512000" />
-      <workItem from="1764548345516" duration="12773000" />
+      <workItem from="1764548345516" duration="28341000" />
     </task>
     <task id="LOCAL-00001" summary="Add undo/redo infrastructure and buffer management additions.">
       <option name="closed" value="true" />
@@ -284,7 +298,23 @@
       <option name="project" value="LOCAL" />
       <updated>1764557759844</updated>
     </task>
-    <option name="localTasksCounter" value="15" />
+    <task id="LOCAL-00015" summary="Fix void crash in kge.">
+      <option name="closed" value="true" />
+      <created>1764568264996</created>
+      <option name="number" value="00015" />
+      <option name="presentableId" value="LOCAL-00015" />
+      <option name="project" value="LOCAL" />
+      <updated>1764568264996</updated>
+    </task>
+    <task id="LOCAL-00016" summary="add regex and search/replace functionality to editor">
+      <option name="closed" value="true" />
+      <created>1764574397967</created>
+      <option name="number" value="00016" />
+      <option name="presentableId" value="LOCAL-00016" />
+      <option name="project" value="LOCAL" />
+      <updated>1764574397967</updated>
+    </task>
+    <option name="localTasksCounter" value="17" />
     <servers />
   </component>
   <component name="TypeScriptGeneratedFilesManager">
@@ -312,7 +342,9 @@
     <MESSAGE value="Introduce file picker and GUI configuration with enhancements.&#10;&#10;- Add visual file picker for GUI with toggle support.&#10;- Introduce `GUIConfig` class for loading GUI settings from configuration file.&#10;- Refactor window initialization to support dynamic sizing based on configuration.&#10;- Add macOS-specific handling for fullscreen behavior.&#10;- Improve header inclusion order and minor code cleanup." />
     <MESSAGE value="Add buffer position display and documentation improvements.&#10;&#10;- Display buffer position prefix &quot;[x/N]&quot; in GUI and terminal renderers.&#10;- Improve `kte` and `kge` man pages with frontend usage details and project homepage.&#10;- Update README with GUI invocation instructions.&#10;- Bump version to 1.0.0." />
     <MESSAGE value="Actually add the screenshot." />
-    <option name="LAST_COMMIT_MESSAGE" value="Actually add the screenshot." />
+    <MESSAGE value="Fix void crash in kge." />
+    <MESSAGE value="add regex and search/replace functionality to editor" />
+    <option name="LAST_COMMIT_MESSAGE" value="add regex and search/replace functionality to editor" />
   </component>
   <component name="XSLT-Support.FileAssociations.UIState">
     <expand />

Buffer.cc

@@ -36,6 +36,7 @@ Buffer::Buffer(const Buffer &other)
 	filename_       = other.filename_;
 	is_file_backed_ = other.is_file_backed_;
 	dirty_          = other.dirty_;
+	read_only_      = other.read_only_;
 	mark_set_       = other.mark_set_;
 	mark_curx_      = other.mark_curx_;
 	mark_cury_      = other.mark_cury_;
@@ -60,6 +61,7 @@ Buffer::operator=(const Buffer &other)
 	filename_       = other.filename_;
 	is_file_backed_ = other.is_file_backed_;
 	dirty_          = other.dirty_;
+	read_only_      = other.read_only_;
 	mark_set_       = other.mark_set_;
 	mark_curx_      = other.mark_curx_;
 	mark_cury_      = other.mark_cury_;
@@ -82,6 +84,7 @@ Buffer::Buffer(Buffer &&other) noexcept
 	  filename_(std::move(other.filename_)),
 	  is_file_backed_(other.is_file_backed_),
 	  dirty_(other.dirty_),
+	  read_only_(other.read_only_),
 	  mark_set_(other.mark_set_),
 	  mark_curx_(other.mark_curx_),
 	  mark_cury_(other.mark_cury_),
@@ -112,6 +115,7 @@ Buffer::operator=(Buffer &&other) noexcept
 	filename_       = std::move(other.filename_);
 	is_file_backed_ = other.is_file_backed_;
 	dirty_          = other.dirty_;
+	read_only_      = other.read_only_;
 	mark_set_       = other.mark_set_;
 	mark_curx_      = other.mark_curx_;
 	mark_cury_      = other.mark_cury_;
@@ -364,9 +368,9 @@ Buffer::insert_text(int row, int col, std::string_view text)
 		rows_[y].insert(x, seg);
 		x += seg.size();
 		// Split line at x
-		std::string tail = rows_[y].substr(x);
+  std::string tail = rows_[y].substr(x);
-		rows_[y].erase(x);
+  rows_[y].erase(x);
-		rows_.insert(rows_.begin() + static_cast<std::ptrdiff_t>(y + 1), tail);
+  rows_.insert(rows_.begin() + static_cast<std::ptrdiff_t>(y + 1), Line(tail));
 		y += 1;
 		x = 0;
 		remain.erase(0, pos + 1);
@@ -426,8 +430,8 @@ Buffer::split_line(int row, const int col)
 	const auto y    = static_cast<std::size_t>(row);
 	const auto x    = std::min<std::size_t>(static_cast<std::size_t>(col), rows_[y].size());
 	const auto tail = rows_[y].substr(x);
-	rows_[y].erase(x);
+ rows_[y].erase(x);
-	rows_.insert(rows_.begin() + static_cast<std::ptrdiff_t>(y + 1), tail);
+ rows_.insert(rows_.begin() + static_cast<std::ptrdiff_t>(y + 1), Line(tail));
 }
 
 
@@ -455,7 +459,7 @@ Buffer::insert_row(int row, const std::string_view text)
 		row = 0;
 	if (static_cast<std::size_t>(row) > rows_.size())
 		row = static_cast<int>(rows_.size());
-	rows_.insert(rows_.begin() + row, std::string(text));
+ rows_.insert(rows_.begin() + row, Line(std::string(text)));
 }
 
 

Buffer.h

@@ -16,7 +16,7 @@
 
 class Buffer {
 public:
-	Buffer();
+    Buffer();
 
 	Buffer(const Buffer &other);
 
@@ -77,13 +77,13 @@ public:
 		Line() = default;
 
 
-		Line(const char *s)
+		explicit Line(const char *s)
 		{
 			assign_from(s ? std::string(s) : std::string());
 		}
 
 
-		Line(const std::string &s)
+		explicit Line(const std::string &s)
 		{
 			assign_from(s);
 		}
@@ -139,29 +139,38 @@ public:
 
 
 		// conversions
-		operator std::string() const
+		explicit operator std::string() const
 		{
-			return std::string(buf_.Data() ? buf_.Data() : "", buf_.Size());
+			return {buf_.Data() ? buf_.Data() : "", buf_.Size()};
 		}
 
 
 		// string-like API used by command/renderer layers (implemented via materialization for now)
-		std::string substr(std::size_t pos) const
+		[[nodiscard]] std::string substr(std::size_t pos) const
 		{
 			const std::size_t n = buf_.Size();
 			if (pos >= n)
-				return std::string();
+				return {};
-			return std::string(buf_.Data() + pos, n - pos);
+			return {buf_.Data() + pos, n - pos};
 		}
 
 
-		std::string substr(std::size_t pos, std::size_t len) const
+		[[nodiscard]] std::string substr(std::size_t pos, std::size_t len) const
 		{
 			const std::size_t n = buf_.Size();
 			if (pos >= n)
-				return std::string();
+				return {};
 			const std::size_t take = (pos + len > n) ? (n - pos) : len;
-			return std::string(buf_.Data() + pos, take);
+			return {buf_.Data() + pos, take};
+		}
+
+
+		// minimal find() to support search within a line
+		[[nodiscard]] std::size_t find(const std::string &needle, const std::size_t pos = 0) const
+		{
+			// Materialize to std::string for now; Line is backed by AppendBuffer
+			const auto s = static_cast<std::string>(*this);
+			return s.find(needle, pos);
 		}
 
 
@@ -253,6 +262,14 @@ 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)
+	{
+		filename_ = name;
+		is_file_backed_ = false;
+	}
+
 
 	[[nodiscard]] bool IsFileBacked() const
 	{
@@ -260,26 +277,42 @@ public:
 	}
 
 
-	[[nodiscard]] bool Dirty() const
+ [[nodiscard]] bool Dirty() const
-	{
+ {
-		return dirty_;
+     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_;
+ }
 
 
-	void SetCursor(std::size_t x, std::size_t y)
+	void SetCursor(const std::size_t x, const std::size_t y)
 	{
 		curx_ = x;
 		cury_ = y;
 	}
 
 
-	void SetRenderX(std::size_t rx)
+	void SetRenderX(const std::size_t rx)
 	{
 		rx_ = rx;
 	}
 
 
-	void SetOffsets(std::size_t row, std::size_t col)
+	void SetOffsets(const std::size_t row, const std::size_t col)
 	{
 		rowoffs_ = row;
 		coloffs_ = col;
@@ -299,7 +332,7 @@ public:
 	}
 
 
-	void SetMark(std::size_t x, std::size_t y)
+	void SetMark(const std::size_t x, const std::size_t y)
 	{
 		mark_set_  = true;
 		mark_curx_ = x;
@@ -344,20 +377,21 @@ public:
 	// Undo system accessors (created per-buffer)
 	UndoSystem *Undo();
 
-	const UndoSystem *Undo() const;
+	[[nodiscard]] const UndoSystem *Undo() const;
 
 private:
-	// State mirroring original C struct (without undo_tree)
+    // State mirroring original C struct (without undo_tree)
-	std::size_t curx_    = 0, cury_ = 0; // cursor position in characters
+    std::size_t curx_    = 0, cury_ = 0; // cursor position in characters
-	std::size_t rx_      = 0; // render x (tabs expanded)
+    std::size_t rx_      = 0; // render x (tabs expanded)
-	std::size_t nrows_   = 0; // number of rows
+    std::size_t nrows_   = 0; // number of rows
 	std::size_t rowoffs_ = 0, coloffs_ = 0; // viewport offsets
 	std::vector<Line> rows_; // buffer rows (without trailing newlines)
 	std::string filename_;
-	bool is_file_backed_   = false;
+ bool is_file_backed_   = false;
-	bool dirty_            = false;
+ bool dirty_            = false;
-	bool mark_set_         = false;
+ bool read_only_        = false;
-	std::size_t mark_curx_ = 0, mark_cury_ = 0;
+ bool mark_set_         = false;
+ std::size_t mark_curx_ = 0, mark_cury_ = 0;
 
 	// Per-buffer undo state
 	std::unique_ptr<struct UndoTree> undo_tree_;

CMakeLists.txt

@@ -4,14 +4,15 @@ project(kte)
 include(GNUInstallDirs)
 
 set(CMAKE_CXX_STANDARD 17)
-set(KTE_VERSION "1.0.4")
+set(KTE_VERSION "1.0.5")
 
 # Default to terminal-only build to avoid SDL/OpenGL dependency by default.
 # Enable with -DBUILD_GUI=ON when SDL2/OpenGL/Freetype are available.
-set(BUILD_GUI OFF CACHE BOOL "Enable building the graphical version.")
+set(BUILD_GUI ON CACHE BOOL "Enable building the graphical version.")
 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)
 
 if (CMAKE_HOST_UNIX)
     message(STATUS "Build system is POSIX.")
@@ -55,6 +56,7 @@ set(COMMON_SOURCES
         Buffer.cc
         Editor.cc
         Command.cc
+        HelpText.cc
         KKeymap.cc
         TerminalInputHandler.cc
         TerminalRenderer.cc
@@ -74,6 +76,7 @@ set(COMMON_HEADERS
         Editor.h
         AppendBuffer.h
         Command.h
+        HelpText.h
         KKeymap.h
         InputHandler.h
         TerminalInputHandler.h
@@ -99,6 +102,9 @@ add_executable(kte
 if (KTE_USE_PIECE_TABLE)
     target_compile_definitions(kte PRIVATE KTE_USE_PIECE_TABLE=1)
 endif ()
+if (KTE_UNDO_DEBUG)
+    target_compile_definitions(kte PRIVATE KTE_UNDO_DEBUG=1)
+endif ()
 
 target_link_libraries(kte ${CURSES_LIBRARIES})
 
@@ -121,6 +127,10 @@ if (BUILD_TESTS)
         target_compile_definitions(test_undo PRIVATE KTE_USE_PIECE_TABLE=1)
     endif ()
 
+    if (KTE_UNDO_DEBUG)
+        target_compile_definitions(test_undo PRIVATE KTE_UNDO_DEBUG=1)
+    endif ()
+
 
     target_link_libraries(test_undo ${CURSES_LIBRARIES})
 endif ()
@@ -153,6 +163,9 @@ if (${BUILD_GUI})
             GUIFrontend.cc
             GUIFrontend.h)
     target_compile_definitions(kge PRIVATE KTE_BUILD_GUI=1 KTE_DEFAULT_GUI=1 KTE_FONT_SIZE=${KTE_FONT_SIZE})
+    if (KTE_UNDO_DEBUG)
+        target_compile_definitions(kge PRIVATE KTE_UNDO_DEBUG=1)
+    endif ()
     target_link_libraries(kge ${CURSES_LIBRARIES} imgui)
 
     # On macOS, build kge as a proper .app bundle

Command.h

@@ -23,8 +23,10 @@ enum class CommandId {
 	Refresh, // force redraw
 	KPrefix, // show "C-k _" prompt in status when entering k-command
 	FindStart, // begin incremental search (placeholder)
+	RegexFindStart, // begin regex search (C-r)
+	RegexpReplace, // begin regex search & replace (C-t)
+	SearchReplace, // begin search & replace (two-step prompt)
 	OpenFileStart, // begin open-file prompt
-	// GUI: visual file picker
 	VisualFilePickerToggle,
 	// Buffers
 	BufferSwitchStart, // begin buffer switch prompt
@@ -71,6 +73,8 @@ enum class CommandId {
 	IndentRegion, // indent region (C-k =)
 	UnindentRegion, // unindent region (C-k -)
 	ReflowParagraph, // reflow paragraph to column width (ESC q)
+	// Read-only buffers
+	ToggleReadOnly, // toggle current buffer read-only (C-k ')
 	// Buffer operations
 	ReloadBuffer, // reload buffer from disk (C-k l)
 	MarkAllAndJumpEnd, // set mark at beginning, jump to end (C-k a)
@@ -78,6 +82,8 @@ enum class CommandId {
 	JumpToLine, // prompt for line and jump (C-k g)
 	ShowWorkingDirectory, // Display the current working directory in the editor message.
 	ChangeWorkingDirectory, // Change the editor's current directory.
+	// Help
+	ShowHelp, // open +HELP+ buffer with manual text (C-k h)
 	// Meta
 	UnknownKCommand, // arg: single character that was not recognized after C-k
 };

Editor.h

@@ -301,8 +301,22 @@ public:
 	}
 
 
-	// --- Generic Prompt subsystem (for search, open-file, save-as, etc.) ---
+ // --- Generic Prompt subsystem (for search, open-file, save-as, etc.) ---
-	enum class PromptKind { None = 0, Search, OpenFile, SaveAs, Confirm, BufferSwitch, GotoLine, Chdir };
+ enum class PromptKind {
+     None = 0,
+     Search,
+     RegexSearch,
+     RegexReplaceFind,  // step 1 of Regex Search & Replace: find pattern
+     RegexReplaceWith,  // step 2 of Regex Search & Replace: replacement text
+     OpenFile,
+     SaveAs,
+     Confirm,
+     BufferSwitch,
+     GotoLine,
+     Chdir,
+     ReplaceFind,  // step 1 of Search & Replace: find what
+     ReplaceWith   // step 2 of Search & Replace: replace with
+ };
 
 
 	void StartPrompt(PromptKind kind, const std::string &label, const std::string &initial)
@@ -504,9 +518,20 @@ private:
 	std::string prompt_text_;
 	std::string pending_overwrite_path_;
 
-	// GUI-only state (safe no-op in terminal builds)
+    // GUI-only state (safe no-op in terminal builds)
-	bool file_picker_visible_ = false;
+    bool file_picker_visible_ = false;
-	std::string file_picker_dir_;
+    std::string file_picker_dir_;
+
+    // Temporary state for Search & Replace flow
+public:
+    void SetReplaceFindTmp(const std::string &s) { replace_find_tmp_ = s; }
+    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_;
+    std::string replace_with_tmp_;
 };
 
 #endif // KTE_EDITOR_H

GUIRenderer.cc

@@ -7,6 +7,7 @@
 #include <string>
 
 #include <imgui.h>
+#include <regex>
 
 #include "GUIRenderer.h"
 #include "Buffer.h"
@@ -190,7 +191,7 @@ GUIRenderer::Draw(Editor &ed)
             } else {
                 // Convert pixel X to a render-column target including horizontal col offset
                 // Use our own tab expansion of width 8 to match command layer logic.
-                const std::string &line_clicked = lines[by];
+                std::string line_clicked = static_cast<std::string>(lines[by]);
                 const std::size_t tabw          = 8;
                 // We iterate source columns computing absolute rendered column (rx_abs) from 0,
                 // then translate to viewport-space by subtracting Coloffs.
@@ -241,31 +242,92 @@ GUIRenderer::Draw(Editor &ed)
         }
 		// Cache current horizontal offset in rendered columns
 		const std::size_t coloffs_now = buf->Coloffs();
-		for (std::size_t i = rowoffs; i < lines.size(); ++i) {
+  for (std::size_t i = rowoffs; i < lines.size(); ++i) {
-			// Capture the screen position before drawing the line
+            // Capture the screen position before drawing the line
-			ImVec2 line_pos         = ImGui::GetCursorScreenPos();
+            ImVec2 line_pos         = ImGui::GetCursorScreenPos();
-			const std::string &line = lines[i];
+            std::string line = static_cast<std::string>(lines[i]);
 
-			// Expand tabs to spaces with width=8 and apply horizontal scroll offset
+            // Expand tabs to spaces with width=8 and apply horizontal scroll offset
-			const std::size_t tabw = 8;
+            const std::size_t tabw = 8;
-			std::string expanded;
+            std::string expanded;
-			expanded.reserve(line.size() + 16);
+            expanded.reserve(line.size() + 16);
-			std::size_t rx_abs_draw = 0; // rendered column for drawing
+            std::size_t rx_abs_draw = 0; // rendered column for drawing
-			// Emit entire line (ImGui child scrolling will handle clipping)
+            // Compute search highlight ranges for this line in source indices
-			for (std::size_t src = 0; src < line.size(); ++src) {
+            bool search_mode = ed.SearchActive() && !ed.SearchQuery().empty();
-				char c = line[src];
+            std::vector<std::pair<std::size_t, std::size_t>> hl_src_ranges;
-				if (c == '\t') {
+            if (search_mode) {
-					std::size_t adv = (tabw - (rx_abs_draw % tabw));
+                // If we're in RegexSearch or RegexReplaceFind mode, compute ranges using regex; otherwise plain substring
-					// Emit spaces for the tab
+                if (ed.PromptActive() && (ed.CurrentPromptKind() == Editor::PromptKind::RegexSearch || ed.CurrentPromptKind() == Editor::PromptKind::RegexReplaceFind)) {
-					expanded.append(adv, ' ');
+                    try {
-					rx_abs_draw += adv;
+                        std::regex rx(ed.SearchQuery());
-				} else {
+                        for (auto it = std::sregex_iterator(line.begin(), line.end(), rx);
-					expanded.push_back(c);
+                             it != std::sregex_iterator(); ++it) {
-					rx_abs_draw += 1;
+                            const auto &m = *it;
-				}
+                            std::size_t sx = static_cast<std::size_t>(m.position());
-			}
+                            std::size_t ex = sx + static_cast<std::size_t>(m.length());
+                            hl_src_ranges.emplace_back(sx, ex);
+                        }
+                    } catch (const std::regex_error &) {
+                        // ignore invalid patterns here; status line already shows the error
+                    }
+                } else {
+                    const std::string &q = ed.SearchQuery();
+                    std::size_t pos = 0;
+                    while (!q.empty() && (pos = line.find(q, pos)) != std::string::npos) {
+                        hl_src_ranges.emplace_back(pos, pos + q.size());
+                        pos += q.size();
+                    }
+                }
+            }
+            auto src_to_rx = [&](std::size_t upto_src_exclusive) -> std::size_t {
+                std::size_t rx = 0;
+                std::size_t s  = 0;
+                while (s < upto_src_exclusive && s < line.size()) {
+                    if (line[s] == '\t')
+                        rx += (tabw - (rx % tabw));
+                    else
+                        rx += 1;
+                    ++s;
+                }
+                return rx;
+            };
+            // Draw background highlights (under text)
+            if (search_mode && !hl_src_ranges.empty()) {
+                // Current match emphasis
+                bool has_current = ed.SearchMatchLen() > 0 && ed.SearchMatchY() == i;
+                std::size_t cur_x = has_current ? ed.SearchMatchX() : 0;
+                std::size_t cur_end = has_current ? (ed.SearchMatchX() + ed.SearchMatchLen()) : 0;
+                for (const auto &rg : hl_src_ranges) {
+                    std::size_t sx = rg.first, ex = rg.second;
+                    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
+                    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);
+                    // 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);
+                    ImGui::GetWindowDrawList()->AddRectFilled(p0, p1, col);
+                }
+            }
+            // Emit entire line (ImGui child scrolling will handle clipping)
+            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 {
+                    expanded.push_back(c);
+                    rx_abs_draw += 1;
+                }
+            }
 
-			ImGui::TextUnformatted(expanded.c_str());
+            ImGui::TextUnformatted(expanded.c_str());
 
 			// Draw a visible cursor indicator on the current line
 			if (i == cy) {
@@ -304,8 +366,7 @@ GUIRenderer::Draw(Editor &ed)
   ImGui::GetWindowDrawList()->AddRectFilled(p0, p1, bg_col);
   // If a prompt is active, replace the entire status bar with the prompt text
   if (ed.PromptActive()) {
-      std::string msg = ed.PromptLabel();
+      std::string label = ed.PromptLabel();
-      if (!msg.empty()) msg += ": ";
       std::string ptext = ed.PromptText();
       auto kind         = ed.CurrentPromptKind();
       if (kind == Editor::PromptKind::OpenFile || kind == Editor::PromptKind::SaveAs ||
@@ -322,14 +383,62 @@ GUIRenderer::Draw(Editor &ed)
               }
           }
       }
-      msg += ptext;
 
       float pad = 6.f;
-      ImVec2 msg_sz = ImGui::CalcTextSize(msg.c_str());
       float left_x = p0.x + pad;
+      float right_x = p1.x - pad;
+      float max_px = std::max(0.0f, right_x - left_x);
+
+      std::string prefix;
+      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) {
+          // Trim from left until it fits by pixel width
+          std::string tail = ptext;
+          ImVec2 tail_sz = ImGui::CalcTextSize(tail.c_str());
+          if (tail_sz.x > avail_px) {
+              // Remove leading chars until it fits
+              // Use a simple loop; text lengths are small here
+              size_t start = 0;
+              // To avoid O(n^2) worst-case, remove chunks
+              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;
+                  start += skip;
+                  std::string candidate = tail.substr(start);
+                  ImVec2 cand_sz = ImGui::CalcTextSize(candidate.c_str());
+                  if (cand_sz.x <= avail_px) {
+                      tail = candidate;
+                      tail_sz = cand_sz;
+                      break;
+                  }
+              }
+              if (ImGui::CalcTextSize(tail.c_str()).x > avail_px && !tail.empty()) {
+                  // As a last resort, ensure fit by chopping exactly
+                  // binary reduce
+                  size_t lo = 0, hi = tail.size();
+                  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;
+                  }
+                  tail = tail.substr(lo);
+              }
+          }
+          final_msg = prefix + tail;
+      } else {
+          final_msg = prefix + ptext;
+      }
+
+      ImVec2 msg_sz = ImGui::CalcTextSize(final_msg.c_str());
       ImGui::PushClipRect(ImVec2(p0.x, p0.y), ImVec2(p1.x, p1.y), true);
       ImGui::SetCursorScreenPos(ImVec2(left_x, p0.y + (bar_h - msg_sz.y) * 0.5f));
-      ImGui::TextUnformatted(msg.c_str());
+      ImGui::TextUnformatted(final_msg.c_str());
       ImGui::PopClipRect();
       // Advance cursor to after the bar to keep layout consistent
       ImGui::Dummy(ImVec2(x1 - x0, bar_h));

HelpText.cc

@@ -0,0 +1,55 @@
+/*
+ * HelpText.cc - embedded/customizable help content
+ */
+
+#include "HelpText.h"
+
+
+std::string
+HelpText::Text()
+{
+	// Customize the help text here. This string will be used by C-k h first.
+	// You can keep it empty to fall back to the manpage or built-in defaults.
+	// Note: keep newline characters as-is; the renderer splits lines on '\n'.
+
+	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"
+		"  inspired by Antirez' kilo text editor by way of someone's writeup of the\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"
+		"  C-k '        Toggle read-only\n"
+		"  C-k -        Unindent region\n"
+		"  C-k =        Indent region\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 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 g        Jump to line\n"
+		"  C-k h        Show this help\n"
+		"  C-k l        Reload buffer from disk\n"
+		"  C-k n        Previous buffer\n"
+		"  C-k o        Change working directory (prompt)\n"
+		"  C-k p        Next buffer\n"
+		"  C-k q        Quit (confirm if dirty)\n"
+		"  C-k r        Redo\n"
+		"  C-k s        Save buffer\n"
+		"  C-k u        Undo\n"
+		"  C-k v        Toggle visual file picker (GUI)\n"
+		"  C-k w        Show working directory\n"
+		"  C-k x        Save and quit\n"
+		"\n"
+		"ESC/Alt commands:\n"
+		"  ESC q        Reflow paragraph\n"
+		"  ESC BACKSPACE Delete previous word\n"
+		"  ESC d        Delete next word\n"
+		"  Alt-w        Copy region to kill ring\n\n"
+		"Buffers:\n  +HELP+ is read-only. Press C-k ' to toggle if you need to edit; C-k h restores it.\n"
+	);
+}

HelpText.h

@@ -0,0 +1,17 @@
+/*
+ * HelpText.h - embedded/customizable help content
+ */
+#ifndef KTE_HELPTEXT_H
+#define KTE_HELPTEXT_H
+
+#include <string>
+
+class HelpText {
+public:
+    // Returns the embedded help text as a single string with newlines.
+    // Project maintainers can customize the returned string below
+    // (in HelpText.cc) without touching the help command logic.
+    static std::string Text();
+};
+
+#endif // KTE_HELPTEXT_H

KKeymap.cc

@@ -33,6 +33,10 @@ KLookupKCommand(const int ascii_key, const bool ctrl, CommandId &out) -> bool
 		out = CommandId::Redo; // C-k r (redo)
 		return true;
 	}
+    if (ascii_key == '\'') {
+        out = CommandId::ToggleReadOnly; // C-k ' (toggle read-only)
+        return true;
+    }
 
 	switch (k_lower) {
 	case 'a':
@@ -59,6 +63,9 @@ KLookupKCommand(const int ascii_key, const bool ctrl, CommandId &out) -> bool
 	case 'g':
 		out = CommandId::JumpToLine;
 		return true;
+	case 'h':
+		out = CommandId::ShowHelp;
+		return true;
 	case 'j':
 		out = CommandId::JumpToMark;
 		return true;
@@ -114,7 +121,7 @@ auto
 KLookupCtrlCommand(const int ascii_key, CommandId &out) -> bool
 {
 	const int k = KLowerAscii(ascii_key);
-	switch (k) {
+ switch (k) {
 	case 'w':
 		out = CommandId::KillRegion; // C-w
 		return true;
@@ -145,6 +152,15 @@ KLookupCtrlCommand(const int ascii_key, CommandId &out) -> bool
 	case 's':
 		out = CommandId::FindStart;
 		return true;
+ case 'r':
+        out = CommandId::RegexFindStart; // C-r regex search
+        return true;
+    case 't':
+        out = CommandId::RegexpReplace; // C-t regex search & replace
+        return true;
+	case 'h':
+		out = CommandId::SearchReplace; // C-h: search & replace
+		return true;
 	case 'l':
 		out = CommandId::Refresh;
 		return true;

ROADMAP.md

@@ -1,10 +1,10 @@
 ROADMAP / TODO:
 
-- [ ] Search + Replace
+- [x] Search + Replace
-- [ ] Regex search + replace
+- [x] Regex search + replace
 - [ ] The undo system should actually work
-- [ ] Able to mark buffers as read-only
+- [x] Able to mark buffers as read-only
-- [ ] Built-in help text
+- [x] Built-in help text
-- [ ] Shorten paths in the homedir with ~
+- [x] Shorten paths in the homedir with ~
-- [ ] When the filename is longer than the message window, scoot left to
+- [x] When the filename is longer than the message window, scoot left to
-  to keep it in view
+  keep it in view

TerminalRenderer.cc

@@ -3,6 +3,7 @@
 #include <filesystem>
 #include <cstdlib>
 #include <ncurses.h>
+#include <regex>
 #include <string>
 
 #include "TerminalRenderer.h"
@@ -40,100 +41,140 @@ TerminalRenderer::Draw(Editor &ed)
 		std::size_t coloffs = buf->Coloffs();
 
 		const int tabw = 8;
-		for (int r = 0; r < content_rows; ++r) {
+  for (int r = 0; r < content_rows; ++r) {
-			move(r, 0);
+            move(r, 0);
-			std::size_t li = rowoffs + static_cast<std::size_t>(r);
+            std::size_t li = rowoffs + static_cast<std::size_t>(r);
-			std::size_t render_col = 0;
+            std::size_t render_col = 0;
-			std::size_t src_i = 0;
+            std::size_t src_i = 0;
-			bool do_hl = ed.SearchActive() && li == ed.SearchMatchY() && ed.SearchMatchLen() > 0;
+            // Compute matches for this line if search highlighting is active
-			std::size_t mx = do_hl ? ed.SearchMatchX() : 0;
+            bool search_mode = ed.SearchActive() && !ed.SearchQuery().empty();
-			std::size_t mlen = do_hl ? ed.SearchMatchLen() : 0;
+            std::vector<std::pair<std::size_t, std::size_t>> ranges; // [start, end)
-			bool hl_on = false;
+            if (search_mode && li < lines.size()) {
-			int written = 0;
+                std::string sline = static_cast<std::string>(lines[li]);
-			if (li < lines.size()) {
+                // If regex search prompt is active (RegexSearch or RegexReplaceFind), use regex to compute highlight ranges
-				const std::string &line = lines[li];
+                if (ed.PromptActive() && (ed.CurrentPromptKind() == Editor::PromptKind::RegexSearch || ed.CurrentPromptKind() == Editor::PromptKind::RegexReplaceFind)) {
-				src_i                   = 0;
+                    try {
-				render_col              = 0;
+                        std::regex rx(ed.SearchQuery());
-				while (written < cols) {
+                        for (auto it = std::sregex_iterator(sline.begin(), sline.end(), rx);
-					char ch       = ' ';
+                             it != std::sregex_iterator(); ++it) {
-					bool from_src = false;
+                            const auto &m = *it;
-					if (src_i < line.size()) {
+                            std::size_t sx = static_cast<std::size_t>(m.position());
-						unsigned char c = static_cast<unsigned char>(line[src_i]);
+                            std::size_t ex = sx + static_cast<std::size_t>(m.length());
-						if (c == '\t') {
+                            ranges.emplace_back(sx, ex);
-							std::size_t next_tab = tabw - (render_col % tabw);
+                        }
-							if (render_col + next_tab <= coloffs) {
+                    } catch (const std::regex_error &) {
-								render_col += next_tab;
+                        // ignore invalid patterns here; status shows error
-								++src_i;
+                    }
-								continue;
+                } else {
-							}
+                    const std::string &q = ed.SearchQuery();
-							// Emit spaces for tab
+                    std::size_t pos      = 0;
-							if (render_col < coloffs) {
+                    while (!q.empty() && (pos = sline.find(q, pos)) != std::string::npos) {
-								// skip to coloffs
+                        ranges.emplace_back(pos, pos + q.size());
-								std::size_t to_skip = std::min<std::size_t>(
+                        pos += q.size();
-									next_tab, coloffs - render_col);
+                    }
-								render_col += to_skip;
+                }
-								next_tab -= to_skip;
+            }
-							}
+            auto is_src_in_hl = [&](std::size_t si) -> bool {
-							// Now render visible spaces
+                if (ranges.empty()) return false;
-							while (next_tab > 0 && written < cols) {
+                // ranges are non-overlapping and ordered by construction
-								bool in_hl = do_hl && src_i >= mx && src_i < mx + mlen;
+                // linear scan is fine for now
-								// highlight by source index
+                for (const auto &rg : ranges) {
-								if (in_hl && !hl_on) {
+                    if (si < rg.first) break;
-									attron(A_STANDOUT);
+                    if (si >= rg.first && si < rg.second) return true;
-									hl_on = true;
+                }
-								}
+                return false;
-								if (!in_hl && hl_on) {
+            };
-									attroff(A_STANDOUT);
+            // Track current-match to optionally emphasize
-									hl_on = false;
+            const bool has_current = ed.SearchActive() && ed.SearchMatchLen() > 0;
-								}
+            const std::size_t cur_mx = has_current ? ed.SearchMatchX() : 0;
-								addch(' ');
+            const std::size_t cur_my = has_current ? ed.SearchMatchY() : 0;
-								++written;
+            const std::size_t cur_mend = has_current ? (ed.SearchMatchX() + ed.SearchMatchLen()) : 0;
-								++render_col;
+            bool hl_on = false;
-								--next_tab;
+            bool cur_on = false;
-							}
+            int written = 0;
-							++src_i;
+            if (li < lines.size()) {
-							continue;
+                std::string line = static_cast<std::string>(lines[li]);
-						} else {
+                src_i                   = 0;
-							// normal char
+                render_col              = 0;
-							if (render_col < coloffs) {
+                while (written < cols) {
-								++render_col;
+                    char ch       = ' ';
-								++src_i;
+                    bool from_src = false;
-								continue;
+                    if (src_i < line.size()) {
-							}
+                        unsigned char c = static_cast<unsigned char>(line[src_i]);
-							ch       = static_cast<char>(c);
+                        if (c == '\t') {
-							from_src = true;
+                            std::size_t next_tab = tabw - (render_col % tabw);
-						}
+                            if (render_col + next_tab <= coloffs) {
-					} else {
+                                render_col += next_tab;
-						// beyond EOL, fill spaces
+                                ++src_i;
-						ch       = ' ';
+                                continue;
-						from_src = false;
+                            }
-					}
+                            // Emit spaces for tab
-					if (do_hl) {
+                            if (render_col < coloffs) {
-						bool in_hl = from_src && src_i >= mx && src_i < mx + mlen;
+                                // skip to coloffs
-						if (in_hl && !hl_on) {
+                                std::size_t to_skip = std::min<std::size_t>(
-							attron(A_STANDOUT);
+                                    next_tab, coloffs - render_col);
-							hl_on = true;
+                                render_col += to_skip;
-						}
+                                next_tab -= to_skip;
-						if (!in_hl && hl_on) {
+                            }
-							attroff(A_STANDOUT);
+                            // Now render visible spaces
-							hl_on = false;
+                            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;
-					addch(static_cast<unsigned char>(ch));
+                                // Toggle highlight attributes
-					++written;
+                                int attr = 0;
-					++render_col;
+                                if (in_hl) attr |= A_STANDOUT;
-					if (from_src)
+                                if (in_cur) attr |= A_BOLD;
-						++src_i;
+                                if ((attr & A_STANDOUT) && !hl_on) { attron(A_STANDOUT); hl_on = true; }
-					if (src_i >= line.size() && written >= cols)
+                                if (!(attr & A_STANDOUT) && hl_on) { attroff(A_STANDOUT); hl_on = false; }
-						break;
+                                if ((attr & A_BOLD) && !cur_on) { attron(A_BOLD); cur_on = true; }
-				}
+                                if (!(attr & A_BOLD) && cur_on) { attroff(A_BOLD); cur_on = false; }
-			}
+                                addch(' ');
-			if (hl_on) {
+                                ++written;
-				attroff(A_STANDOUT);
+                                ++render_col;
-				hl_on = false;
+                                --next_tab;
-			}
+                            }
-			clrtoeol();
+                            ++src_i;
-		}
+                            continue;
+                        } else {
+                            // normal char
+                            if (render_col < coloffs) {
+                                ++render_col;
+                                ++src_i;
+                                continue;
+                            }
+                            ch       = static_cast<char>(c);
+                            from_src = true;
+                        }
+                    } else {
+                        // beyond EOL, fill spaces
+                        ch       = ' ';
+                        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;
+                    if (in_hl && !hl_on) { 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; }
+                    addch(static_cast<unsigned char>(ch));
+                    ++written;
+                    ++render_col;
+                    if (from_src)
+                        ++src_i;
+                    if (src_i >= line.size() && written >= cols)
+                        break;
+                }
+            }
+            if (hl_on) {
+                attroff(A_STANDOUT);
+                hl_on = false;
+            }
+            if (cur_on) {
+                attroff(A_BOLD);
+                cur_on = false;
+            }
+            clrtoeol();
+        }
 
 		// Place terminal cursor at logical position accounting for tabs and coloffs
 		std::size_t cy = buf->Cury();
@@ -161,9 +202,7 @@ TerminalRenderer::Draw(Editor &ed)
  // If a prompt is active, replace the status bar with the full prompt text
  if (ed.PromptActive()) {
      // Build prompt text: "Label: text" and shorten HOME path for file-related prompts
-     std::string msg = ed.PromptLabel();
+     std::string label = ed.PromptLabel();
-     if (!msg.empty())
-         msg += ": ";
      std::string ptext = ed.PromptText();
      auto kind         = ed.CurrentPromptKind();
      if (kind == Editor::PromptKind::OpenFile || kind == Editor::PromptKind::SaveAs ||
@@ -181,7 +220,30 @@ TerminalRenderer::Draw(Editor &ed)
              }
          }
      }
-     msg += ptext;
+     // Prefer keeping the tail of the filename visible when it exceeds the window
+     std::string msg;
+     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) {
+         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
+             std::string whole = msg + ptext;
+             if ((int)whole.size() > cols)
+                 whole = whole.substr(whole.size() - cols);
+             msg = whole;
+         } else {
+             if ((int)ptext.size() > avail) {
+                 ptext = ptext.substr(ptext.size() - avail);
+             }
+             msg += ptext;
+         }
+     } else {
+         // Non-file prompts: simple concatenation and clip by terminal
+         msg += ptext;
+     }
 
      // Draw left-aligned, clipped to width
      if (!msg.empty())
@@ -233,6 +295,9 @@ TerminalRenderer::Draw(Editor &ed)
 		left += fname;
 		if (b && b->Dirty())
 			left += " *";
+		// Append read-only indicator
+		if (b && b->IsReadOnly())
+			left += " [RO]";
 		// Append total line count as "<n>L"
 		if (b) {
 			unsigned long lcount = static_cast<unsigned long>(b->Rows().size());

default-gui.nix

@@ -1,53 +0,0 @@
-{
-  lib,
-  stdenv,
-  cmake,
-  ncurses,
-  SDL2,
-  libGL,
-  xorg,
-  installShellFiles,
-  ...
-}:
-let
-  cmakeContent = builtins.readFile ./CMakeLists.txt;
-  cmakeLines = lib.splitString "\n" cmakeContent;
-  versionLine = lib.findFirst (l: builtins.match ".*set\\(KTE_VERSION \".+\"\\).*" l != null) (throw "KTE_VERSION not found in CMakeLists.txt") cmakeLines;
-  version = builtins.head (builtins.match ".*set\\(KTE_VERSION \"(.+)\"\\).*" versionLine);
-in
-stdenv.mkDerivation {
-  pname = "kte";
-  inherit version;
-
-  src = lib.cleanSource ./.;
-
-  nativeBuildInputs = [
-    cmake
-    ncurses
-    SDL2
-    libGL
-    xorg.libX11
-    installShellFiles
-  ];
-
-  cmakeFlags = [
-    "-DBUILD_GUI=ON"
-    "-DCMAKE_BUILD_TYPE=Debug"
-  ];
-
-  installPhase = ''
-    runHook preInstall
-
-    mkdir -p $out/bin
-    cp kte $out/bin/
-    cp kge $out/bin/
-
-    installManPage ../docs/kte.1
-    installManPage ../docs/kge.1
-
-    mkdir -p $out/share/icons
-    cp ../kge.png $out/share/icons/
-
-    runHook postInstall
-  '';
-}

default-nogui.nix

@@ -1,42 +0,0 @@
-{
-  lib,
-  stdenv,
-  cmake,
-  ncurses,
-  installShellFiles,
-  ...
-}:
-let
-  cmakeContent = builtins.readFile ./CMakeLists.txt;
-  cmakeLines = lib.splitString "\n" cmakeContent;
-  versionLine = lib.findFirst (l: builtins.match ".*set\\(KTE_VERSION \".+\"\\).*" l != null) (throw "KTE_VERSION not found in CMakeLists.txt") cmakeLines;
-  version = builtins.head (builtins.match ".*set\\(KTE_VERSION \"(.+)\"\\).*" versionLine);
-in
-stdenv.mkDerivation {
-  pname = "kte";
-  inherit version;
-
-  src = lib.cleanSource ./.;
-
-  nativeBuildInputs = [
-    cmake
-    ncurses
-    installShellFiles
-  ];
-
-  cmakeFlags = [
-    "-DBUILD_GUI=OFF"
-    "-DCMAKE_BUILD_TYPE=Debug"
-  ];
-
-  installPhase = ''
-    runHook preInstall
-
-    mkdir -p $out/bin
-    cp kte $out/bin/
-
-    installManPage ../docs/kte.1
-
-    runHook postInstall
-  '';
-}

default.nix

@@ -7,12 +7,16 @@
   libGL,
   xorg,
   installShellFiles,
+
+  graphical ? false,
   ...
 }:
 let
   cmakeContent = builtins.readFile ./CMakeLists.txt;
   cmakeLines = lib.splitString "\n" cmakeContent;
-  versionLine = lib.findFirst (l: builtins.match ".*set\\(KTE_VERSION \".+\"\\).*" l != null) (throw "KTE_VERSION not found in CMakeLists.txt") cmakeLines;
+  versionLine = lib.findFirst (
+    l: builtins.match ".*set\\(KTE_VERSION \".+\"\\).*" l != null
+  ) (throw "KTE_VERSION not found in CMakeLists.txt") cmakeLines;
   version = builtins.head (builtins.match ".*set\\(KTE_VERSION \"(.+)\"\\).*" versionLine);
 in
 stdenv.mkDerivation {
@@ -24,14 +28,16 @@ stdenv.mkDerivation {
   nativeBuildInputs = [
     cmake
     ncurses
+    installShellFiles
+  ]
+  ++ lib.optionals graphical [
     SDL2
     libGL
     xorg.libX11
-    installShellFiles
   ];
 
   cmakeFlags = [
-    "-DBUILD_GUI=ON"
+    "-DBUILD_GUI=${if graphical then "ON" else "OFF"}"
     "-DCMAKE_BUILD_TYPE=Debug"
   ];
 
@@ -40,14 +46,17 @@ stdenv.mkDerivation {
 
     mkdir -p $out/bin
     cp kte $out/bin/
-    cp kge $out/bin/
 
     installManPage ../docs/kte.1
-    installManPage ../docs/kge.1
 
+  ''
+  + lib.optionalString graphical ''
+    cp kge $out/bin/
+    installManPage ../docs/kge.1
     mkdir -p $out/share/icons
     cp ../kge.png $out/share/icons/
-
+  ''
+  + ''
     runHook postInstall
   '';
 }

flake-gui.nix

@@ -1,55 +0,0 @@
-# flake.nix
-{
-  description = "kte  ImGui/SDL2 text editor";
-
-  inputs = {
-    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
-    flake-utils.url = "github:numtide/flake-utils";
-  };
-
-  outputs = { self, nixpkgs, flake-utils }:
-    flake-utils.lib.eachDefaultSystem (system:
-      let
-        pkgs = nixpkgs.legacyPackages.${system};
-      in {
-        packages.default = pkgs.stdenv.mkDerivation {
-          pname = "kte";
-          version = "0.1.0";
-          src = ./.;
-
-          nativeBuildInputs = [ pkgs.cmake pkgs.pkg-config ];
-          buildInputs = with pkgs; [
-            ncurses
-            SDL2
-            libGL
-            xorg.libX11
-          ];
-
-          cmakeFlags = [
-            "-DBUILD_GUI=ON"
-            "-DCURSES_NEED_NCURSES=TRUE"
-            "-DCURSES_NEED_WIDE=TRUE"
-          ];
-
-          # Alternative (even stronger): completely hide the broken module
-          preConfigure = ''
-            # If the project ships its own FindSDL2.cmake in cmake/, hide it
-            if [ -f cmake/FindSDL2.cmake ]; then
-              mv cmake/FindSDL2.cmake cmake/FindSDL2.cmake.disabled
-              echo "Disabled bundled FindSDL2.cmake"
-            fi
-          '';
-
-          meta = with pkgs.lib; {
-            description = "kte  ImGui/SDL2 GUI editor";
-            mainProgram = "kte";
-            platforms = platforms.linux;
-          };
-        };
-
-        devShells.default = pkgs.mkShell {
-          inputsFrom = [ self.packages.${system}.default ];
-          packages = with pkgs; [ gdb clang-tools ];
-        };
-      });
-}

flake.nix

@@ -3,16 +3,18 @@
 
   inputs.nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
 
-  outputs = inputs @ { self, nixpkgs, ... }:
+  outputs =
+    inputs@{ self, nixpkgs, ... }:
     let
       eachSystem = nixpkgs.lib.genAttrs nixpkgs.lib.systems.flakeExposed;
       pkgsFor = system: import nixpkgs { inherit system; };
-    in {
+    in
-      packages = eachSystem (system: {
+    {
-        default = (pkgsFor system).callPackage ./default-nogui.nix { };
+      packages = eachSystem (system: rec {
-        kge     = (pkgsFor system).callPackage ./default-gui.nix   { };
+        default = kte;
-        kte     = (pkgsFor system).callPackage ./default-nogui.nix { };
+        full = kge;
-        full    = (pkgsFor system).callPackage ./default.nix       { };
+        kte = (pkgsFor system).callPackage ./default.nix { graphical = false; };
+        kge = (pkgsFor system).callPackage ./default.nix { graphical = true; };
       });
     };
-}
+}