Modularize insertion/deletion

include/editor.h

@@ -115,5 +115,7 @@ void cursor_left(Editor *editor, uint32_t number);
 void cursor_right(Editor *editor, uint32_t number);
 void ensure_scroll(Editor *editor);
 void apply_edit(std::vector<Span> &spans, uint32_t x, int64_t y);
+void edit_erase(Editor *editor, uint32_t pos, uint32_t len);
+void edit_insert(Editor *editor, uint32_t pos, char *data, uint32_t len);
 
 #endif

include/knot.h

@@ -100,7 +100,7 @@ char *read(Knot *root, uint32_t offset, uint32_t len);
 void split(Knot *node, uint32_t offset, Knot **left, Knot **right);
 
 // Used to convert a byte offset to a line number that contains that byte
-uint32_t byte_to_line(Knot *node, uint32_t offset);
+uint32_t byte_to_line(Knot *node, uint32_t offset, uint32_t *out_col);
 
 // Used to convert a line number to a byte offset (start of the line)
 // also sets out_len to the length of the line

include/utils.h

@@ -36,7 +36,7 @@ struct Coord {
   uint32_t col;
 };
 
-uint32_t grapheme_strlen(const char *s);
+uint32_t visual_width(const char *s);
 uint32_t get_visual_col_from_bytes(const char *line, uint32_t byte_limit);
 uint32_t get_bytes_from_visual_col(const char *line,
                                    uint32_t target_visual_col);