import * as graphics from "./graphics_core.mjs";
export * from "./graphics_core.mjs";

import { range, iter_2d } from "./utils/range.mjs";
import * as entity from "./entity.mjs";
import * as world from "./world.mjs";



const canvas = document.getElementById("canvas");
const canvas_context = canvas.getContext("2d");
graphics.set_size(canvas.width, canvas.height);

const BASE_SCALE = 81;

export function draw_tile (x, y, size = BASE_SCALE) {
	graphics.fill_rect(x, y, size, size);
}

function checkerboard (x, y) {
	return ((x ^ y) & 1) === 0;
}

export function draw_floor (start_x, start_y, scale, invert = false) {
	iter_2d(range(0, world.BOX_SIZE - 1), (x, y) => {
		if (checkerboard(x, y) !== invert) {
			graphics.set_color("#aaa");
		} else {
			graphics.set_color("#888");
		}
		const [visual_x, visual_y] = project_pos(x, y, scale);
		draw_tile(start_x + visual_x, start_y + visual_y, scale);
	});
}

export function draw_world (box, start_x = 0, start_y = 0, scale = BASE_SCALE) {
	draw_floor(start_x, start_y, scale, !checkerboard(start_x, start_y));

	iter_2d(range(0, world.BOX_SIZE - 1), (x, y) => {
		const tile = world.get_tile(box, x, y);
		const [visual_x, visual_y] = project_pos(x, y, scale);

		switch (tile.type) {
			case "box": {
				draw_world(tile.box, start_x + visual_x, start_y + visual_y, scale / world.BOX_SIZE);
				break;
			}
			case "paint": {
				graphics.set_color(tile.color);
				draw_tile(start_x + visual_x, start_y + visual_y, scale);
				break;
			}
		}
	});

	entity.for_each((entity, id) => {
		if (entity.box !== box) return;
		graphics.set_color(entity.color);
		const [visual_x, visual_y] = project_pos(entity.x, entity.y, scale);
		draw_tile(start_x + visual_x, start_y + visual_y, scale);
	});
}

function project_pos (x, y, scale) {
	return [x, y].map(a => a * scale);
}

export function render () {
	graphics.render(canvas_context);
}