var canvas;
var context;
var lastTime;
var updateIntervalId;

var camera = { x: 0, y: 0, center: { x: 0, y: 0 }, movementSpeed: 3 };
var isDragging = false;
var dragCompleted = false;
var startDrag = { x: 0, y: 0 };
var dragDelta = { x: 0, y: 0 };
var keys = [];

var server;
var socketHandler = {
	onmessage: (message) => { console.log(message);},
	onopen: (data) => { console.log(data);},
	onclose: (data) => { console.log(data);},
	onError: (data) => { console.error(data);},
};

var spritesheet;
var sprites;
var background;

var room = {
	width: 2048,
	height: 1440,
	center: { x: 1024, y: 720 },
	tileSize: { width: 16, height: 16 },
};

var player = {
	x: 3 * room.tileSize.width,
	y: 3 * room.tileSize.height,
	width: room.tileSize.width,
	height: room.tileSize.height,
	center: { x: room.tileSize.width / 2, y: room.tileSize.height / 2 },
	angle: 90 * Math.PI / 180,
	rotationSpeed: 3 * Math.PI / 180,
	movementSpeed: 3,
	target: { x: 3 * room.tileSize.width, y: 3 * room.tileSize.height },
};
var floater = {
	position: {
	x: 0,
	y: 0,
	},
	width: room.tileSize.width,
	height: room.tileSize.height,
	center: { x: room.tileSize.width / 2, y: room.tileSize.height / 2 },
};
var tweenId = -1;
function animate() {
	context.save();
	context.translate(0.5, 0.5);
	clearFrame(context);
	draw(context);
	context.restore();
	requestAnimationFrame(animate);
}

function clearFrame(context) {
	context.fillStyle = "#283848";
	context.beginPath();
	context.rect(0, 0, canvas.width, canvas.height);
	context.fill();
}

function init() {
	lastTime = new Date().getUTCMilliseconds();
	context = canvas.getContext('2d');

	keys = [];
	for (let i = 0; i < 256; i++) {
		keys[i] = false;
	}

	onResize();
	initBackground();
	initFloater();
}

function update(delta) {
	updateCamera(delta);
	updateBackground(delta);
	updatePlayer(delta);
	updateFloater(delta);
	Tween.update();
}

function draw(context) {
	context.save();
	context.translate(-camera.x + dragDelta.x, -camera.y + dragDelta.y);

	drawBackground(context);
	drawPlayer(context);
	drawFloater(context);

	context.restore();
}

function onResize() {
	let dpi = window.devicePixelRatio;
	canvas.width = canvas.clientWidth;
	canvas.height = canvas.clientHeight;
	context.width = canvas.clientWidth / dpi;
	context.height = canvas.clientHeight / dpi;

	let deltaX = camera.center.x - canvas.width / 2;
	let deltaY = camera.center.y - canvas.height / 2;
	camera.center.x = canvas.width / 2;
	camera.center.y = canvas.height / 2;

	camera.x += deltaX;
	camera.y += deltaY;
}

function onKeyDown(event) {
	keys[event.keyCode] = true;
}

function onKeyUp(event) {
	keys[event.keyCode] = false;
}

function onMouseMove(event) {
	if (isDragging) {
		dragDelta.x = event.clientX - startDrag.x;
		dragDelta.y = event.clientY - startDrag.y;
	}
}

function onMouseDown(event) {
	if (isDragging) {
		return;
	}
	dragCompleted = false;
	if (event.button == 0) {
		isDragging = true;
	}

	startDrag.x = event.clientX;
	startDrag.y = event.clientY;
	dragDelta.x = 0;
	dragDelta.y = 0;
	startDrag.time = new Date().getUTCMilliseconds();
}

function onMouseUp(event) {
	if (event.button == 2) { //startDrag.time + 100 >= new Date().getUTCMilliseconds()
		player.target.x = (Math.floor((camera.x + startDrag.x) / room.tileSize.width) * room.tileSize.width);
		player.target.y = (Math.floor((camera.y + startDrag.y) / room.tileSize.height) * room.tileSize.height);
		return;
	}

	if (isDragging) {
		isDragging = false;
		dragCompleted = true;
	}
}

function onRightClick(event) {
	event.preventDefault();
}

function onTouchStart(event) {
	if (event.touches.length == 2) {
		isDragging = true;
		startDrag.x = parseInt(event.targetTouches[0].clientX);
		startDrag.y = parseInt(event.targetTouches[0].clientY);
		dragDelta.x = 0;
		dragDelta.y = 0;
		startDrag.time = new Date().getUTCMilliseconds();
	}
}

function onTouchMove(event) {
	if (event.touches.length == 2) {
		dragDelta.x = parseInt(event.targetTouches[0].clientX) - startDrag.x;
		dragDelta.y = parseInt(event.targetTouches[0].clientY) - startDrag.y;
	}

}

function onTouchEnd(event) {
	if (isDragging) {
		isDragging = false;
		dragCompleted = true;
		return;
	}

	if (event.touches.length == 0) { //I've let go of all points
		if (!isDragging && !dragCompleted) {
			player.target.x = (Math.floor((camera.x + parseInt(event.changedTouches[0].clientX)) / room.tileSize.width) * room.tileSize.width);
			player.target.y = (Math.floor((camera.y + parseInt(event.changedTouches[0].clientY)) / room.tileSize.height) * room.tileSize.height);
		}
	}
}

document.addEventListener("DOMContentLoaded", event => {
	canvas = document.createElement("canvas");
	document.getElementById("game").appendChild(canvas);
	server = new Server(
		`http://roguelike.eyeofmidas.net:8080`,
		`ws://roguelike.eyeofmidas.net:14700`,
	);

	server.attachWebsocketHandler(socketHandler);

	spritesheet = new Spritesheet("./assets", "Tilesheet/monochrome_transparent_packed.png", room.tileSize.width, room.tileSize.height, 0);
	spritesheet.load().then(() => {
		sprites = new ColorSpriteCache(spritesheet);
		buildSprites();
		init();
		animate();
		server.websocketConnect();
	})

	updateIntervalId = setInterval(() => {
		let currentTime = new Date().getUTCMilliseconds();
		update(1 + ((currentTime - lastTime) / 1000));
		lastTime = currentTime;
	}, 16);
});

window.addEventListener("resize", onResize);
window.addEventListener("keydown", onKeyDown);
window.addEventListener("keyup", onKeyUp);
window.addEventListener("mousedown", onMouseDown);
window.addEventListener("mousemove", onMouseMove);
window.addEventListener("mouseup", onMouseUp);
window.addEventListener("contextmenu", onRightClick);

window.addEventListener("touchstart", onTouchStart);
window.addEventListener("touchmove", onTouchMove);
window.addEventListener("touchend", onTouchEnd);


function updateCamera(delta) {
	if (keys[KeyCode.Up]) {
		camera.y += -camera.movementSpeed * delta;
	}

	if (keys[KeyCode.Down]) {
		camera.y += camera.movementSpeed * delta;
	}

	if (keys[KeyCode.Left]) {
		camera.x += -camera.movementSpeed * delta;
	}

	if (keys[KeyCode.Right]) {
		camera.x += camera.movementSpeed * delta;
	}
}

function updateBackground(delta) {
	let isOutOfBounds = false;
	if (camera.y + canvas.height > (room.center.y * room.tileSize.height)) {
		camera.y = (room.center.y * room.tileSize.height) - canvas.height;
	}

	if (camera.y < -(room.center.y * room.tileSize.height)) {
		camera.y = -(room.center.y * room.tileSize.height);
	}

	if (camera.x + canvas.width > (room.center.x * room.tileSize.width)) {
		camera.x = (room.center.x * room.tileSize.width) - canvas.width;
	}

	if (camera.x < -(room.center.x * room.tileSize.width)) {
		camera.x = -(room.center.x * room.tileSize.width);
	}

	if ((camera.y + canvas.height) - dragDelta.y > (room.center.y * room.tileSize.height)) {
		isOutOfBounds = true;
	}

	if (camera.y - dragDelta.y < -(room.center.y * room.tileSize.height)) {
		isOutOfBounds = true;
	}

	if ((camera.x + canvas.width) - dragDelta.x > (room.center.x * room.tileSize.width)) {
		isOutOfBounds = true;
	}

	if (camera.x - dragDelta.x < -(room.center.x * room.tileSize.width)) {
		isOutOfBounds = true;
	}

	if (dragCompleted) {
		if (isOutOfBounds) {
			camera.x -= dragDelta.x * 0.1;
			camera.y -= dragDelta.y * 0.1;
			dragDelta.x = dragDelta.x * 0.90;
			dragDelta.y = dragDelta.y * 0.90;
			if (Math.abs(dragDelta.x) <= 1 && Math.abs(dragDelta.y) <= 1) {
				dragDelta.x = 0;
				dragDelta.y = 0;
				dragCompleted = false;
			}
		} else {
			camera.x -= dragDelta.x;
			camera.y -= dragDelta.y;
			dragDelta.x = 0;
			dragDelta.y = 0;
			dragCompleted = false;
		}
	}
}

SpriteKeys = {};
SpriteKeys.Bat1 = 410;
SpriteKeys.Hero1 = 25;
SpriteKeys.Grass1 = 5;
SpriteKeys.Grass2 = 6;
SpriteKeys.Grass3 = 7;
SpriteKeys.Floor1 = 2;
SpriteKeys.Floor2 = 3;
SpriteKeys.Floor3 = 4;
SpriteKeys.OutsideWallNW = 640;
SpriteKeys.OutsideWallN = 641;
SpriteKeys.OutsideWallNE = 642;
SpriteKeys.OutsideWallW = 688;
SpriteKeys.OutsideWallE = 690;
SpriteKeys.OutsideWallSW = 736;
SpriteKeys.OutsideWallS = 737;
SpriteKeys.OutsideWallSE = 738;

ColorSprites = {};
ColorSprites.GreenGrass1 = 1;
ColorSprites.GreenGrass2 = 2;
ColorSprites.GreenGrass3 = 3;
ColorSprites.BrownDirt1 = 4;
ColorSprites.BrownDirt2 = 5;
ColorSprites.BrownDirt3 = 6;
ColorSprites.BlackBat1 = 7;
ColorSprites.YellowHero1 = 8;
ColorSprites.GrayWallNW = 9;
ColorSprites.GrayWallN = 10;
ColorSprites.GrayWallNE = 11;
ColorSprites.GrayWallW = 12;
ColorSprites.GrayWallE = 13;
ColorSprites.GrayWallSW = 14;
ColorSprites.GrayWallS = 15;
ColorSprites.GrayWallSE = 16;

function buildSprites() {
	sprites.add(ColorSprites.GreenGrass1, room.tileSize.width, room.tileSize.height, SpriteKeys.Grass1, "#25591f");
	sprites.add(ColorSprites.GreenGrass2, room.tileSize.width, room.tileSize.height, SpriteKeys.Grass2, "#25591f");
	sprites.add(ColorSprites.GreenGrass3, room.tileSize.width, room.tileSize.height, SpriteKeys.Grass3, "#25591f");
	sprites.add(ColorSprites.BlackBat1, room.tileSize.width, room.tileSize.height, SpriteKeys.Bat1, "#080808");
	sprites.add(ColorSprites.YellowHero1, room.tileSize.width, room.tileSize.height, SpriteKeys.Hero1, "#DADA22");

	sprites.add(ColorSprites.BrownDirt1, room.tileSize.width, room.tileSize.height, SpriteKeys.Floor1, "#CD853F");
	sprites.add(ColorSprites.BrownDirt2, room.tileSize.width, room.tileSize.height, SpriteKeys.Floor2, "#CD853F");
	sprites.add(ColorSprites.BrownDirt3, room.tileSize.width, room.tileSize.height, SpriteKeys.Floor3, "#CD853F");

	sprites.add(ColorSprites.GrayWallNW, room.tileSize.width, room.tileSize.height, SpriteKeys.OutsideWallNW, "#868686");
	sprites.add(ColorSprites.GrayWallN, room.tileSize.width, room.tileSize.height, SpriteKeys.OutsideWallN, "#868686");
	sprites.add(ColorSprites.GrayWallNE, room.tileSize.width, room.tileSize.height, SpriteKeys.OutsideWallNE, "#868686");
	sprites.add(ColorSprites.GrayWallW, room.tileSize.width, room.tileSize.height, SpriteKeys.OutsideWallW, "#868686");
	sprites.add(ColorSprites.GrayWallE, room.tileSize.width, room.tileSize.height, SpriteKeys.OutsideWallE, "#868686");
	sprites.add(ColorSprites.GrayWallSW, room.tileSize.width, room.tileSize.height, SpriteKeys.OutsideWallSW, "#868686");
	sprites.add(ColorSprites.GrayWallS, room.tileSize.width, room.tileSize.height, SpriteKeys.OutsideWallS, "#868686");
	sprites.add(ColorSprites.GrayWallSE, room.tileSize.width, room.tileSize.height, SpriteKeys.OutsideWallSE, "#868686");
}

function initBackground() {
	background = document.createElement("canvas");
	background.width = room.width * room.tileSize.width;
	background.height = room.height * room.tileSize.height;
	loadRoom();
}

async function loadRoom(x = 0, y = 0, z = 0) {
	let roomData = await server.apiGet(`/room/${x},${y},${z}`);
	room = roomData.room;
	background = document.createElement("canvas");
	background.width = room.width * room.tileSize.width;
	background.height = room.height * room.tileSize.height;
	let backgroundContext = background.getContext("2d");
	roomData.backgroundRegions.forEach(region => {
		backgroundContext.fillStyle = region.color;
		backgroundContext.beginPath();
		backgroundContext.rect(region.x * room.tileSize.width, region.y * room.tileSize.height, region.width * room.tileSize.width, region.height * room.tileSize.height);
		backgroundContext.fill();
	});

	for(let x in roomData.backgroundTiles) {
		for(let y in roomData.backgroundTiles[x]) {
			sprites.drawOnGrid(backgroundContext, roomData.backgroundTiles[x][y], { x: x, y: y }, room.tileSize);
		}
	};
}

function drawBackground(context) {
	context.drawImage(background, -(room.center.x * room.tileSize.width), -(room.center.y * room.tileSize.height));
}

function updatePlayer(delta) {
	if (player.target.y == player.y) {
		if (keys[KeyCode.W]) {
			player.target.y += -room.tileSize.height;
		}

		if (keys[KeyCode.S]) {
			player.target.y += room.tileSize.height;
		}
	}

	if (player.target.x == player.x) {
		if (keys[KeyCode.A]) {
			player.target.x += -room.tileSize.width;
		}

		if (keys[KeyCode.D]) {
			player.target.x += room.tileSize.width;
		}
	}

	if (Math.abs(player.x - player.target.x) <= player.movementSpeed) {
		player.x = player.target.x;
	}

	if (Math.abs(player.y - player.target.y) <= player.movementSpeed) {
		player.y = player.target.y;
	}

	if (player.target.x != player.x || player.target.y != player.y) {
		let angle = (Math.atan2(player.target.y - player.y, player.target.x - player.x));
		player.x += player.movementSpeed * Math.cos(angle);
		player.y += player.movementSpeed * Math.sin(angle);


	}
}
function drawPlayer(context) {
	context.save();
	context.translate(player.x, player.y);
	let hero = sprites.get(ColorSprites.YellowHero1);
	context.drawImage(hero.image, 0, 0);
	context.restore();
}

function initFloater() {
	floaterToRandomPoint();
}

function floaterToRandomPoint() {
	let randomPoint = {position: { x: 0, y: 0 }};
	randomPoint.position.x = Math.floor(Math.floor((320 * Math.random() - 160) / room.tileSize.width) * room.tileSize.width);
	randomPoint.position.y = Math.floor(Math.floor((320 * Math.random() - 160) / room.tileSize.height) * room.tileSize.height);
	let distance = Math.sqrt(
		Math.pow(randomPoint.position.x - floater.position.x, 2) +
		Math.pow(randomPoint.position.y - floater.position.y, 2)
	);
	tweenId = Tween.create(floater, randomPoint, distance * 8, Tween.Easing.Cubic.EaseInOut, () => {
		setTimeout(floaterToRandomPoint, Math.floor(5 * Math.random() + 1) * 1000);
	});
}

function updateFloater(delta) {

}

function drawFloater(context) {
	context.save();
	context.translate(floater.position.x, floater.position.y);
	let bat = sprites.get(ColorSprites.BlackBat1);
	context.drawImage(bat.image, 0, 0);
	context.restore();
}