function rgba(r, g, b, a) {
	const buffer = Uint8Array.allocPlain(4);
	buffer[0] = r;
	buffer[1] = g;
	buffer[2] = b;
	buffer[3] = a;
	return buffer;
}

const PAD_BUTTON_START = 0x1000;
const PAD_BUTTON_A = 0x0100;
const RED_COLOR = rgba(255, 0, 0, 255);
const GREEN_COLOR = rgba(0, 255, 0, 255);

function rgba_compare(rgba1, rgba2) {
	return (rgba1[0] == rgba2[0]) &&
		(rgba1[1] == rgba2[1]) &&
		(rgba1[2] == rgba2[2]) &&
		(rgba1[3] == rgba2[3]);
}

globalThis.rectangle_color = RED_COLOR;

function swap_colors() {
	if (rgba_compare(rectangle_color, RED_COLOR)) {
		rectangle_color = GREEN_COLOR;
	} else if (rgba_compare(rectangle_color, GREEN_COLOR)) {
		rectangle_color = RED_COLOR;
	}
}

function start() {
}

function update() {
	const pressed = wii.pad.buttons_down();

	if (pressed & PAD_BUTTON_START) {
		wii.print("exiting from js");
		wii.exit();
	}

	if (pressed & PAD_BUTTON_A) {
		wii.print("a pressed");
		swap_colors();
	}

	wii.grrlib.fill_screen(rgba(255, 255, 255, 255));
	wii.grrlib.rectangle(0, 0, 320, 240, rectangle_color, true);
}