Lots of updates:

1. Scrolling and click to set the cursor works.
2. GUI now uses Brass Mono as the font.
3. A lot of stability and other updates.

TerminalRenderer.cc

@@ -0,0 +1,183 @@
+#include "TerminalRenderer.h"
+
+#include <ncurses.h>
+#include <cstdio>
+
+#include "Editor.h"
+#include "Buffer.h"
+
+// Version string expected to be provided by build system as KTE_VERSION_STR
+#ifndef KTE_VERSION_STR
+#  define KTE_VERSION_STR "dev"
+#endif
+
+TerminalRenderer::TerminalRenderer() = default;
+
+TerminalRenderer::~TerminalRenderer() = default;
+
+
+void
+TerminalRenderer::Draw(Editor &ed)
+{
+	// Determine terminal size and keep editor dimensions in sync
+	int rows, cols;
+	getmaxyx(stdscr, rows, cols);
+
+	// Clear screen
+	erase();
+
+	const Buffer *buf = ed.CurrentBuffer();
+	int content_rows  = rows - 1; // last line is status
+
+	if (buf) {
+		const auto &lines   = buf->Rows();
+		std::size_t rowoffs = buf->Rowoffs();
+		std::size_t coloffs = buf->Coloffs();
+
+		const int tabw = 8;
+		for (int r = 0; r < content_rows; ++r) {
+			move(r, 0);
+			std::size_t li = rowoffs + static_cast<std::size_t>(r);
+			std::size_t render_col = 0;
+			std::size_t src_i = 0;
+			bool do_hl = ed.SearchActive() && li == ed.SearchMatchY() && ed.SearchMatchLen() > 0;
+			std::size_t mx = do_hl ? ed.SearchMatchX() : 0;
+			std::size_t mlen = do_hl ? ed.SearchMatchLen() : 0;
+			bool hl_on = false;
+			int written = 0;
+			if (li < lines.size()) {
+				const std::string &line = lines[li];
+				src_i                   = 0;
+				render_col              = 0;
+				while (written < cols) {
+					char ch       = ' ';
+					bool from_src = false;
+					if (src_i < line.size()) {
+						unsigned char c = static_cast<unsigned char>(line[src_i]);
+						if (c == '\t') {
+							std::size_t next_tab = tabw - (render_col % tabw);
+							if (render_col + next_tab <= coloffs) {
+								render_col += next_tab;
+								++src_i;
+								continue;
+							}
+							// Emit spaces for tab
+							if (render_col < coloffs) {
+								// skip to coloffs
+								std::size_t to_skip = std::min<std::size_t>(
+									next_tab, coloffs - render_col);
+								render_col += to_skip;
+								next_tab -= to_skip;
+							}
+							// Now render visible spaces
+							while (next_tab > 0 && written < cols) {
+								bool in_hl = do_hl && src_i >= mx && src_i < mx + mlen;
+								// highlight by source index
+								if (in_hl && !hl_on) {
+									attron(A_STANDOUT);
+									hl_on = true;
+								}
+								if (!in_hl && hl_on) {
+									attroff(A_STANDOUT);
+									hl_on = false;
+								}
+								addch(' ');
+								++written;
+								++render_col;
+								--next_tab;
+							}
+							++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;
+					}
+					if (do_hl) {
+						bool in_hl = from_src && src_i >= mx && src_i < mx + mlen;
+						if (in_hl && !hl_on) {
+							attron(A_STANDOUT);
+							hl_on = true;
+						}
+						if (!in_hl && hl_on) {
+							attroff(A_STANDOUT);
+							hl_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;
+			}
+			clrtoeol();
+		}
+
+		// Place terminal cursor at logical position accounting for tabs and coloffs
+		std::size_t cy = buf->Cury();
+		std::size_t rx = buf->Rx(); // render x computed by command layer
+		int cur_y      = static_cast<int>(cy) - static_cast<int>(buf->Rowoffs());
+		int cur_x      = static_cast<int>(rx) - static_cast<int>(buf->Coloffs());
+		if (cur_y >= 0 && cur_y < content_rows && cur_x >= 0 && cur_x < cols) {
+			move(cur_y, cur_x);
+		}
+	} else {
+		mvaddstr(0, 0, "[no buffer]");
+	}
+
+	// Status line (inverse)
+	move(rows - 1, 0);
+	attron(A_REVERSE);
+	char status[1024];
+	const char *fname = (buf && buf->IsFileBacked()) ? buf->Filename().c_str() : "(new)";
+	int dirty         = (buf && buf->Dirty()) ? 1 : 0;
+ // New compact status: "kte v<version> | <filename>* | row:col [mk row:col]"
+ int row1 = 0, col1 = 0;
+ int mrow1 = 0, mcol1 = 0;
+ int have_mark = 0;
+ if (buf) {
+     row1 = static_cast<int>(buf->Cury()) + 1;
+     col1 = static_cast<int>(buf->Curx()) + 1;
+     if (buf->MarkSet()) {
+         have_mark = 1;
+         mrow1 = static_cast<int>(buf->MarkCury()) + 1;
+         mcol1 = static_cast<int>(buf->MarkCurx()) + 1;
+     }
+ }
+ if (have_mark) {
+     snprintf(status, sizeof(status), " kte %s | %s%s | %d:%d | mk %d:%d ",
+              KTE_VERSION_STR,
+              fname,
+              dirty ? "*" : "",
+              row1, col1,
+              mrow1, mcol1);
+ } else {
+     snprintf(status, sizeof(status), " kte %s | %s%s | %d:%d ",
+              KTE_VERSION_STR,
+              fname,
+              dirty ? "*" : "",
+              row1, col1);
+ }
+	addnstr(status, cols);
+	clrtoeol();
+	attroff(A_REVERSE);
+
+	refresh();
+}