import { AssetManager } from "./assets.ts";
import { ClientWorld } from "./client_world.ts";
import { InputManager } from "./input_manager.ts";
import { Connection, get_player_name, get_server_url } from "./network.ts";
import { begin_drawing, clear_background, end_drawing, init_font, init_window } from "./renderer/mod.ts";
import { is_stopped, show_fatal_error } from "./fatal.ts";
import { load_client_mods, set_mods_world } from "./mods.ts";

export class ClientLoop {
	running = false;
	last_time = 0;
	world: ClientWorld;

	frame_count = 0;
	last_fps_time = 0;

	constructor(world: ClientWorld) {
		this.world = world;
	}

	start() {
		document.addEventListener("visibilitychange", () => {
			if (!document.hidden) {
				this.last_time = performance.now();
			}
		});

		this.running = true;
		const now = performance.now();
		this.last_time = now;
		this.frame_count = 0;
		this.last_fps_time = this.last_time;
		requestAnimationFrame((time) => this.loop(time));
	}

	stop() {
		this.running = false;
	}

	loop(time: number) {
		if (!this.running || is_stopped()) {
			return;
		}

		const delta = (time - this.last_time) / 1000;

		begin_drawing();
		clear_background(0.69, 0.8, 1, 1.0);
		this.world.update(delta);
		end_drawing();

		this.frame_count += 1;
		const now = performance.now();
		if (now - this.last_fps_time >= 1000) {
			const fps = (this.frame_count * 1000) / (now - this.last_fps_time);
			console.log(`FPS: ${fps.toFixed(2)}`);
			this.frame_count = 0;
			this.last_fps_time = now;
		}

		InputManager.update();

		this.last_time = time;
		requestAnimationFrame((time) => this.loop(time));
	}
}

const canvas = document.getElementById("game") as HTMLCanvasElement;
if (!canvas) {
	throw Error("Canvas was not found");
}

await init_window(canvas);

InputManager.initialize(canvas);

AssetManager.instance.load("bworld:assets_text", "/assets/ASSETS.md");

AssetManager.instance.load("bworld:textures", "/assets/sprites/textures.png");
AssetManager.instance.load("bworld:textures_info", "/assets/sprites/textures.json");

AssetManager.instance.load("bworld:player", "/assets/sprites/player.png");
AssetManager.instance.load("bworld:roguelike", "/assets/sprites/roguelike.png");
AssetManager.instance.load("bworld:ui", "/assets/sprites/ui.png");

AssetManager.instance.load("bworld:m6x11", "/assets/fonts/m6x11.png");
AssetManager.instance.load("bworld:m6x11_fnt", "/assets/fonts/m6x11.fnt");

await AssetManager.instance.load_all();

init_font();

// the game only runs against a server, it owns the world and everything in it
const connection = await Connection.open(get_server_url(), get_player_name());
let mods_loaded = false;
if (connection) {
	console.log(`Connected to ${get_server_url()}`);
	try {
		// blocks, items and textures all come from mods, so this happens before anything else
		await load_client_mods(connection.mods);
		console.log(`Mods: ${connection.mods.map((mod) => `${mod.id} ${mod.version}`).join(", ") || "none"}`);
		mods_loaded = true;
	} catch (e) {
		console.error(e);
		show_fatal_error(`Couldn't load the server's mods: ${e instanceof Error ? e.message : e}`);
		connection.socket.close();
	}
}

if (connection && mods_loaded) {
	const client_world = new ClientWorld(connection);
	set_mods_world(client_world);
	client_world.add_chat("Connected to the server");

	const loop = new ClientLoop(client_world);
	loop.start();

	console.log("Game started");
} else if (!connection) {
	show_fatal_error(`Couldn't connect to the server at ${get_server_url()}`);
}