improve buffer_unsaved_changes

so that making an edit then undoing it doesn't count as making a change

3 files changed, 43 insertions, 12 deletions

diff --git a/buffer.c b/buffer.c
index 33ae6be..7cb1208 100644
--- a/buffer.c
+++ b/buffer.c
@@ -34,6 +34,9 @@ static void buffer_clear_redo_history(TextBuffer *buffer) {
 		buffer_edit_free(edit);
 	}
 	arr_clear(buffer->redo_history);
+	// if the write pos is in the redo history,
+	if (buffer->undo_history_write_pos > arr_len(buffer->undo_history))
+		buffer->undo_history_write_pos = U32_MAX; // get rid of it
 }
 
 static void buffer_clear_undo_history(TextBuffer *buffer) {
@@ -41,8 +44,13 @@ static void buffer_clear_undo_history(TextBuffer *buffer) {
 		buffer_edit_free(edit);
 	}
 	arr_clear(buffer->undo_history);
+	buffer->undo_history_write_pos = U32_MAX;
 }
 
+static void buffer_clear_undo_redo(TextBuffer *buffer) {
+	buffer_clear_undo_history(buffer);
+	buffer_clear_redo_history(buffer);
+}
 
 bool buffer_empty(TextBuffer *buffer) {
 	return buffer->nlines == 1 && buffer->lines[0].len == 0;
@@ -56,12 +64,6 @@ bool buffer_is_untitled(TextBuffer *buffer) {
 	return streq(buffer->filename, TED_UNTITLED);
 }
 
-// clear all undo and redo events
-void buffer_clear_undo_redo(TextBuffer *buffer) {
-	buffer_clear_undo_history(buffer);
-	buffer_clear_redo_history(buffer);
-}
-
 // add this edit to the undo history
 static void buffer_append_edit(TextBuffer *buffer, BufferEdit const *edit) {
 	// whenever an edit is made, clear the redo history
@@ -138,7 +140,7 @@ static bool buffer_pos_valid(TextBuffer *buffer, BufferPos p) {
 bool buffer_unsaved_changes(TextBuffer *buffer) {
 	if (buffer_is_untitled(buffer) && buffer_empty(buffer))
 		return false; // don't worry about empty untitled buffers
-	return buffer->modified;
+	return arr_len(buffer->undo_history) != buffer->undo_history_write_pos;
 }
 
 // code point at position.
@@ -1885,11 +1887,10 @@ bool buffer_save(TextBuffer *buffer) {
 				if (!buffer_haserr(buffer))
 					buffer_seterr(buffer, "Couldn't close file %s.", buffer->filename);
 			}
-			bool success = !buffer_haserr(buffer);
-			if (success) {
-				buffer->modified = false;
-			}
 			buffer->last_write_time = time_last_modified(buffer->filename);
+			bool success = !buffer_haserr(buffer);
+			if (success)
+				buffer->undo_history_write_pos = arr_len(buffer->undo_history);
 			return success;
 		} else {
 			buffer_seterr(buffer, "Couldn't open file %s for writing: %s.", buffer->filename, strerror(errno));
diff --git a/ted.h b/ted.h
index 5b8d5c6..7d7f7c7 100644
--- a/ted.h
+++ b/ted.h
@@ -131,11 +131,14 @@ typedef struct {
 	bool is_line_buffer; // "line buffers" are buffers which can only have one line of text (used for inputs)
 	bool selection;
 	bool store_undo_events; // set to false to disable undo events
-	bool modified; // has the buffer been modified since it was loaded/saved?
+	// This is set to true whenever a change is made to the buffer, and never set to false by buffer_ functions.
+	// (Distinct from buffer_unsaved_changes)
+	bool modified;
 	float x1, y1, x2, y2;
 	u32 nlines;
 	u32 lines_capacity;
 
+	u32 undo_history_write_pos; // where in the undo history was the last write? used by buffer_unsaved_changes
 	u32 longest_line_on_screen; // length of the longest line on screen. used to determine how far right we can scroll.
 
 	// to cache syntax highlighting properly, it is important to keep track of the
diff --git a/ui.c b/ui.c
index 49c0dc8..b743d82 100644
--- a/ui.c
+++ b/ui.c
@@ -582,6 +582,7 @@ static void popup_render(Ted *ted, u32 options, char const *title, char const *b
 	text_get_size(font_bold, title, &title_size.x, &title_size.y);
 	v2 title_pos = v2_sub(V2(window_width * 0.5f, y), V2(title_size.x * 0.5f, 0));
 	text_utf8(font_bold, title, title_pos.x, title_pos.y, colors[COLOR_TEXT]);
+	text_render(font_bold);
 
 	// body text
 	float text_x1 = rect_x1(r) + padding;
@@ -598,3 +599,29 @@ static void popup_render(Ted *ted, u32 options, char const *title, char const *b
 
 	text_render(font);
 }
+
+static void checkbox_frame(Ted *ted, bool *value, char const *label, v2 pos) {
+	Font *font = ted->font;
+	float char_height = text_font_char_height(font);
+	float checkbox_size = char_height;
+	Settings const *settings = &ted->settings;
+	u32 const *colors = settings->colors;
+	
+	Rect checkbox_rect = rect(pos, V2(checkbox_size, checkbox_size));
+	
+	for (u32 i = 0; i < ted->nmouse_clicks[SDL_BUTTON_LEFT]; ++i) {
+		if (rect_contains_point(checkbox_rect, ted->mouse_clicks[SDL_BUTTON_LEFT][i])) {
+			*value = !*value;
+		}
+	}
+	
+	if (*value)
+		gl_geometry_rect(checkbox_rect, colors[COLOR_TEXT]);
+	else
+		gl_geometry_rect_border(checkbox_rect, 1, colors[COLOR_TEXT]);
+	v2 text_pos = v2_add(pos, V2(checkbox_size, 0));
+	text_utf8(font, label, text_pos.x, text_pos.y, colors[COLOR_TEXT]);
+	
+	gl_geometry_draw();
+	text_render(font);
+}