Set time to warning color on BT disconnect

src/c/main.c

@@ -65,6 +65,19 @@ static void batt_callback(BatteryChargeState state) {
 	}
 }
 
+static void bt_callback(bool connected) {
+	GColor src = connected ? settings.ColorWarning : s_applied_fg;
+	GColor dst = connected ? s_applied_fg : settings.ColorWarning;
+
+	for (int i = 0; i < 10; ++i) {
+		replace_gbitmap_color(src, dst, s_font_bitmaps[i], NULL);
+	}
+
+	for (int i = 0; i < 4; ++i) {
+		layer_mark_dirty(bitmap_layer_get_layer(s_time_fg_layers[i]));
+	}
+}
+
 static void temp_update_proc(Layer *layer, GContext *ctx) {
 	graphics_context_set_fill_color(ctx, GColorWhite);
 	const uint8_t bar_count = s_temp_level;
@@ -444,6 +457,7 @@ static void init() {
 
 	update_minute_1();
 	batt_callback(battery_state_service_peek());
+	bt_callback(connection_service_peek_pebble_app_connection());
 
 	app_message_register_inbox_received(inbox_received_handler);
 	app_message_open(255, 64);
@@ -456,9 +470,11 @@ static void init() {
 
 	tick_timer_service_subscribe(MINUTE_UNIT, minute_handler);
 	battery_state_service_subscribe(batt_callback);
+	connection_service_subscribe((ConnectionHandlers){.pebble_app_connection_handler = bt_callback});
 }
 
 static void deinit() {
+	connection_service_unsubscribe();
 	battery_state_service_unsubscribe();
 	tick_timer_service_unsubscribe();
 	layer_destroy(s_fuel_layer);