1 files changed, 145 insertions, 0 deletions
diff --git a/autocomplete.c b/autocomplete.c
new file mode 100644
index 0000000..da4ade3
--- /dev/null
+++ b/autocomplete.c
@@ -0,0 +1,145 @@
+// get the thing to be completed (and what buffer it's in)
+// returns false if this is a read only buffer or something
+// call free() on *startp when you're done with it
+static Status autocomplete_get(Ted *ted, char **startp, TextBuffer **bufferp) {
+	TextBuffer *buffer = ted->active_buffer;
+	if (buffer && !buffer->view_only && !buffer->is_line_buffer) {
+		buffer->selection = false;
+		if (is_word(buffer_char_after_cursor(buffer)))
+			buffer_cursor_move_right_words(buffer, 1);
+		else
+			buffer_scroll_to_cursor(buffer);
+		char *start = str32_to_utf8_cstr(buffer_word_at_cursor(buffer));
+		if (*start) {
+			*startp = start;
+			*bufferp = buffer;
+			return true;	
+		} else {
+			// no word at cursor
+			free(start);
+			return false;
+		}
+	} else {
+		return false;
+	}	
+}
+
+// do the actual completion
+static void autocomplete_complete(Ted *ted, char *start, TextBuffer *buffer, char *completion) {
+	char *str = completion + strlen(start);
+	buffer_start_edit_chain(buffer); // don't merge with other edits
+	buffer_insert_utf8_at_cursor(buffer, str);
+	buffer_end_edit_chain(buffer);
+	ted->autocomplete = false;
+}
+
+// open autocomplete, or just do the completion if there's only one suggestion
+static void autocomplete_open(Ted *ted) {
+	char *start;
+	TextBuffer *buffer;
+	ted->cursor_error_time = 0;
+	if (autocomplete_get(ted, &start, &buffer)) {
+		char *completions[2] = {0};
+		size_t ncompletions = tags_beginning_with(ted, start, completions, 2);
+		switch (ncompletions) {
+		case 0:
+			ted->cursor_error_time = time_get_seconds();
+			break;
+		case 1:
+			autocomplete_complete(ted, start, buffer, completions[0]);
+			break;
+		case 2:
+			// open autocomplete selection menu
+			ted->autocomplete = true;
+			break;
+		default: assert(0); break;
+		}
+		free(completions[0]);
+		free(completions[1]);
+		free(start);
+	}
+}
+
+#define AUTOCOMPLETE_NCOMPLETIONS 10 // max # of completions to show
+static void autocomplete_frame(Ted *ted) {
+	Settings const *settings = &ted->settings;
+	u32 const *colors = settings->colors;
+	float const padding = settings->padding;
+	
+	char *start;
+	TextBuffer *buffer;
+	if (autocomplete_get(ted, &start, &buffer)) {
+		Font *font = ted->font;
+		float char_height = text_font_char_height(font);
+		
+		char *completions[AUTOCOMPLETE_NCOMPLETIONS];
+		size_t ncompletions = tags_beginning_with(ted, start, completions, arr_count(completions));
+		float menu_width = 400, menu_height = (float)ncompletions * char_height + 2 * padding;
+		
+		if (ncompletions == 0) {
+			// no completions. close menu.
+			ted->autocomplete = false;
+			return;
+		}
+		
+		
+		v2 cursor_pos = buffer_pos_to_pixels(buffer, buffer->cursor_pos);
+		bool open_up = cursor_pos.y > 0.5f * (buffer->y1 + buffer->y2); // should the completion menu open upwards?
+		bool open_left = cursor_pos.x > 0.5f * (buffer->x1 + buffer->x2);
+		float x = cursor_pos.x, start_y = cursor_pos.y;
+		if (open_left) x -= menu_width;
+		if (open_up)
+			start_y -= menu_height;
+		else
+			start_y += char_height; // put menu below cursor
+		{
+			Rect menu_rect = rect(V2(x, start_y), V2(menu_width, menu_height));
+			gl_geometry_rect(menu_rect, colors[COLOR_MENU_BG]);
+			//gl_geometry_rect_border(menu_rect, 1, colors[COLOR_BORDER]);
+		}
+		
+		// vertical padding
+		start_y += padding;
+		menu_height -= 2 * padding;
+		
+		u16 cursor_entry = (u16)((ted->mouse_pos.y - start_y) / char_height);
+		if (cursor_entry < ncompletions) {
+			// highlight cursor entry
+			Rect r = rect(V2(x, start_y + cursor_entry * char_height), V2(menu_width, char_height));
+			gl_geometry_rect(r, colors[COLOR_MENU_HL]);
+			ted->cursor = ted->cursor_hand;
+			ted->autocomplete_rect = r;
+		}
+		
+		for (uint i = 0; i < ted->nmouse_clicks[SDL_BUTTON_LEFT]; ++i) {
+			v2 click = ted->mouse_clicks[SDL_BUTTON_LEFT][i];
+			if (rect_contains_point(ted->autocomplete_rect, click)) {
+				u16 entry = (u16)((click.y - start_y) / char_height);
+				if (entry < ncompletions) {
+					// entry was clicked on! use this completion.
+					autocomplete_complete(ted, start, buffer, completions[entry]);
+				}
+			}
+		}
+		
+		float y = start_y;
+		TextRenderState state = text_render_state_default;
+		state.min_x = x + padding; state.min_y = y; state.max_x = x + menu_width - padding; state.max_y = y + menu_height;
+		rgba_u32_to_floats(colors[COLOR_TEXT], state.color);
+		for (size_t i = 0; i < ncompletions; ++i) {
+			state.x = x + padding; state.y = y;
+			text_utf8_with_state(font, &state, completions[i]);
+			y += char_height;
+		}
+		
+		gl_geometry_draw();
+		text_render(font);
+		
+		for (size_t i = 0; i < ncompletions; ++i)
+			free(completions[i]);
+	
+		free(start);
+	} else {
+		ted->autocomplete = false;
+	}
+}