// canvas augmentation!

var p = CanvasRenderingContext2D.prototype;
p.circle = function (x, y, radius) {
	this.beginPath();
	this.arc(x, y, radius, 0, Math.PI * 2, true);
};
p.fillCircle = function (x, y, radius) {
	this.circle(x, y, radius);
	this.fill();
	this.beginPath();
};
p.strokeCircle = function (x, y, radius) {
	this.circle(x, y, radius);
	this.stroke();
	this.beginPath();
};
p.ellipse = function (x, y, width, height) {
	this.beginPath();
	for (var i = 0; i < Math.PI * 2; i += Math.PI / 16) {
		this.lineTo(x + (Math.cos(i) * width) / 2, y + (Math.sin(i) * height) / 2);
	}
	this.closePath();
};
p.fillEllipse = function (x, y, width, height) {
	this.ellipse(x, y, width, height);
	this.fill();
	this.beginPath();
};
p.strokeEllipse = function (x, y, width, height) {
	this.ellipse(x, y, width, height);
	this.stroke();
	this.beginPath();
};

p.line = function (x1, y1, x2, y2) {
	this.beginPath();
	this.moveTo(x1, y1);
	this.lineTo(x2, y2);
	this.stroke();
	this.beginPath();
};

function radians(deg) {
	return (deg * Math.PI) / 180;
}
function degrees(rad) {
	return (rad * 180) / Math.PI;
}
function rgb(r, g, b) {
	return (
		'rgb(' +
		clamp(Math.round(r), 0, 255) +
		', ' +
		clamp(Math.round(g), 0, 255) +
		', ' +
		clamp(Math.round(b), 0, 255) +
		')'
	);
}
function rgba(r, g, b, a) {
	return (
		'rgba(' +
		clamp(Math.round(r), 0, 255) +
		', ' +
		clamp(Math.round(g), 0, 255) +
		', ' +
		clamp(Math.round(b), 0, 255) +
		', ' +
		clamp(a, 0, 1) +
		')'
	);
}
function hsl(h, s, l) {
	return 'hsl(' + h + ', ' + clamp(s, 0, 100) + '%, ' + clamp(l, 0, 100) + '%)';
}
function hsla(h, s, l, a) {
	return (
		'hsla(' + h + ', ' + clamp(s, 0, 100) + '%, ' + clamp(l, 0, 100) + '%, ' + clamp(a, 0, 1) + ')'
	);
}

function randomInteger(min, max) {
	if (max === undefined) {
		max = min;
		min = 0;
	}
	return Math.floor(Math.random() * (max + 1 - min)) + min;
}
function random(min, max) {
	if (min === undefined) {
		min = 0;
		max = 1;
	} else if (max === undefined) {
		max = min;
		min = 0;
	}
	return Math.random() * (max - min) + min;
}

function map(value, min1, max1, min2, max2, clampResult) {
	var returnvalue = ((value - min1) / (max1 - min1)) * (max2 - min2) + min2;
	if (clampResult) return clamp(returnvalue, min2, max2);
	else return returnvalue;
}

function clamp(value, min, max) {
	if (max < min) {
		var temp = min;
		min = max;
		max = temp;
	}
	return Math.max(min, Math.min(value, max));
}

function dist(x1, y1, x2, y2) {
	x2 -= x1;
	y2 -= y1;
	return Math.sqrt(x2 * x2 + y2 * y2);
}

var mouseX = 0,
	mouseY = 0,
	lastMouseX = 0,
	lastMouseY = 0,
	frameRate = 60,
	lastUpdate = Date.now(),
	mouseDown = false;

function cjsloop() {
	var now = Date.now();
	var elapsedMils = now - lastUpdate;

	if (typeof window.draw == 'function' && elapsedMils >= 1000 / window.frameRate) {
		window.draw();

		lastUpdate = now - (elapsedMils % (1000 / window.frameRate));
		lastMouseX = mouseX;
		lastMouseY = mouseY;
	}

	requestAnimationFrame(cjsloop);
}

// requestAnimationFrame
// http://paulirish.com/2011/requestanimationframe-for-smart-animating/
// http://my.opera.com/emoller/blog/2011/12/20/requestanimationframe-for-smart-er-animating

// requestAnimationFrame polyfill by Erik Möller
// fixes from Paul Irish and Tino Zijdel

(function () {
	var lastTime = 0;
	var vendors = ['ms', 'moz', 'webkit', 'o'];
	for (var x = 0; x < vendors.length && !window.requestAnimationFrame; ++x) {
		window.requestAnimationFrame = window[vendors[x] + 'RequestAnimationFrame'];
		window.cancelAnimationFrame =
			window[vendors[x] + 'CancelAnimationFrame'] ||
			window[vendors[x] + 'CancelRequestAnimationFrame'];
	}

	if (!window.requestAnimationFrame)
		window.requestAnimationFrame = function (callback, element) {
			var currTime = new Date().getTime();
			var timeToCall = Math.max(0, 16 - (currTime - lastTime));
			var id = window.setTimeout(function () {
				callback(currTime + timeToCall);
			}, timeToCall);
			lastTime = currTime + timeToCall;
			return id;
		};

	if (!window.cancelAnimationFrame)
		window.cancelAnimationFrame = function (id) {
			clearTimeout(id);
		};
})();

window.addEventListener('load', init);

function init() {
	// add touch support
	window.addEventListener('touchmove', (e) => {
		if (mouseDown) {
			let pos = getTouchPos(e);
			mouseX = pos.touchX;
			mouseY = pos.touchY;
		}
	});
	window.addEventListener('touchstart', (e) => {
		mouseDown = true;
		if (typeof onMouseDown == 'function') onMouseDown();
	});
	window.addEventListener('touchend', (e) => {
		mouseDown = false;
		if (typeof onMouseUp == 'function') onMouseUp();
	});
	// mouse support
	window.addEventListener('mousemove', function (e) {
		mouseX = e.clientX;
		mouseY = e.clientY;
	});
	window.addEventListener('mousedown', function (e) {
		mouseDown = true;
		if (typeof onMouseDown == 'function') onMouseDown();
	});
	window.addEventListener('mouseup', function (e) {
		mouseDown = false;
		if (typeof onMouseUp == 'function') onMouseUp();
	});
	window.addEventListener('keydown', function (e) {
		if (typeof onKeyDown == 'function') onKeyDown(e);
	});
	window.addEventListener('keyup', function (e) {
		if (typeof onKeyUp == 'function') onKeyUp(e);
	});

	if (typeof window.setup == 'function') window.setup();
	cjsloop();
}

function getTouchPos(e) {
	if (!e) var e = event;

	if (e.touches) {
		if (e.touches.length == 1) {
			// Only deal with one finger
			var touch = e.touches[0]; // Get the information for finger #1
			touchX = touch.pageX - touch.target.offsetLeft;
			touchY = touch.pageY - touch.target.offsetTop;

			return { touchX, touchY };
		}
	}
}