CE line numbers on the side

ce/edit.c

@@ -35,6 +35,7 @@ struct editor {
   struct cursor cursor;
   size_t col_offset;
   size_t row_offset;
+  size_t total_lines;
 };
 
 static struct editor editor;
@@ -77,6 +78,19 @@ static void update_vert_scroll (size_t screen_rows) {
     editor.row_offset = editor.cursor.line - (screen_rows - 1) + 1;
 }
 
+static size_t count_digits (size_t n) {
+  if (n == 0)
+    return 1;
+
+  size_t count = 0;
+  while (n > 0) {
+    n /= 10;
+    count++;
+  }
+
+  return count;
+}
+
 void edit_start (const char* file_path, const char* text) {
   prepare_lines (text);
   struct arena temp_arena;
@@ -108,6 +122,12 @@ void edit_start (const char* file_path, const char* text) {
     size_t current_idx = 0;
 
     struct list_node_link *line_link, *tmp_line_link;
+
+    list_foreach (editor.lines, line_link, tmp_line_link) editor.total_lines++;
+
+    size_t gutter_width = count_digits (editor.total_lines);
+    size_t effective_cols = (cols > gutter_width + 1) ? cols - (gutter_width + 1) : cols;
+
     list_foreach (editor.lines, line_link, tmp_line_link) {
       if (current_idx < editor.row_offset) {
         current_idx++;
@@ -123,6 +143,11 @@ void edit_start (const char* file_path, const char* text) {
       bbptr += w;
       bb_remaining -= w;
 
+      w = snprintf (bbptr, bb_remaining, ANSIQ_SETFG_CYAN "%*zu " ANSIQ_GR_RESET, gutter_width,
+                    current_idx + 1);
+      bbptr += w;
+      bb_remaining -= w;
+
       size_t part1_len = line->gb.gap_start;
       size_t part2_len = line->gb.size - line->gb.gap_end;
 
@@ -132,8 +157,8 @@ void edit_start (const char* file_path, const char* text) {
         size_t start = editor.col_offset;
         size_t len = part1_len - start;
 
-        if (len > cols)
+        if (len > effective_cols)
-          len = cols;
+          len = effective_cols;
 
         w = snprintf (bbptr, bb_remaining, "%.*s", (int)len, &line->gb.buffer[start]);
         bbptr += w;
@@ -141,7 +166,7 @@ void edit_start (const char* file_path, const char* text) {
         current_col += len;
       }
 
-      if (current_col < cols && part2_len > 0) {
+      if (current_col < effective_cols && part2_len > 0) {
         size_t skip = 0;
         if (editor.col_offset > part1_len)
           skip = editor.col_offset - part1_len;
@@ -149,8 +174,8 @@ void edit_start (const char* file_path, const char* text) {
         if (skip < part2_len) {
           size_t len = part2_len - skip;
 
-          if (current_col + len > cols)
+          if (current_col + len > effective_cols)
-            len = cols - current_col;
+            len = effective_cols - current_col;
 
           w = snprintf (bbptr, bb_remaining, "%.*s", (int)len,
                         &line->gb.buffer[line->gb.gap_end + skip]);
@@ -172,13 +197,13 @@ void edit_start (const char* file_path, const char* text) {
     bb_remaining -= w;
 
     w = snprintf (bbptr, bb_remaining, "Editing %s; line %zu col %zu", file_path,
-                  editor.cursor.line, editor.cursor.col);
+                  editor.cursor.line + 1, editor.cursor.col + 1);
     bbptr += w;
     bb_remaining -= w;
 
     w = snprintf (bbptr, bb_remaining, ANSIQ_DYN_CUR_SET ANSIQ_CUR_VISIBLE,
                   (int)(editor.cursor.line - editor.row_offset) + 1,
-                  (int)(editor.cursor.col - editor.col_offset) + 1);
+                  (int)(editor.cursor.col - editor.col_offset) + 1 + (int)gutter_width + 1);
     bbptr += w;
     bb_remaining -= w;
 
@@ -274,6 +299,7 @@ void edit_start (const char* file_path, const char* text) {
       break;
     }
 
+    editor.total_lines = 0;
     arena_reset (&temp_arena);
   }