/**
 * wm.animate  - an experimental animation library that uses matrices and requestAnimationFrame
 * Only supports x/y now and is used by the scroller library
 */
define(["jcl"],function($){
	/**
	  * @license MIT - https://github.com/darius/requestAnimationFrame/commit/4f27a5a21902a883330da4663bea953b2f96cb15#diff-9879d6db96fd29134fc802214163b95a

	    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
	    MIT license

	    Adapted from https://gist.github.com/paulirish/1579671 which derived from 
	    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, Tino Zijdel, Andrew Mao, Klemen Slavič, Darius Bacon
	*/

	if (!Date.now)
	    Date.now = function() {
	        return new Date().getTime();
	    };

	(function() {
	    var vendors = ["webkit", "moz","ms"];
	    for (var i = 0; i < vendors.length && !window.requestAnimationFrame; ++i) {
	        var vp = vendors[i];
	        window.requestAnimationFrame = window[vp+"RequestAnimationFrame"];
	        window.cancelAnimationFrame = (window[vp+"CancelAnimationFrame"] || window[vp+"CancelRequestAnimationFrame"]);
	    }
	    if (/iP(ad|hone|od).*OS 6/.test(window.navigator.userAgent) || !window.requestAnimationFrame || !window.cancelAnimationFrame) {
	        var lastTime = 0;
	        window.requestAnimationFrame = function(callback) {
	            var now = Date.now();
	            var nextTime = Math.max(lastTime + 16, now);
	            return setTimeout(function() { callback(lastTime = nextTime); },
	                              nextTime - now);
	        };
	        window.cancelAnimationFrame = clearTimeout;
	    }
	}());
	
	/*-------------------------------------------------------*/
    var cache = [];
    var objId = function(obj) {
        if (!obj.wmAnimateId) obj.wmAnimateId = $.uuid();
        return obj.wmAnimateId;
    };
    var getEl = function(elID) {
        if (typeof elID === "string" || elID instanceof String) {
            return document.getElementById(elID);
        } else if ($.is$(elID)) {
            return elID[0];
        } else {
            return elID;
        }
    };
    var getAnimate = function(obj, options) {
        var tmp, id, el = getEl(obj);
        //first one
        id = objId(el);
        if (cache[id]) {
            if(options)
                cache[id].animate(options);
            tmp = cache[id];
        } else {
            tmp = Animate(el, options);
            cache[id] = tmp;
        }
        return tmp;
    };
    $.fn.animate = function(opts) {
        var tmp = getAnimate(this[0], opts);
        return tmp;
    };



    var Animate = function(elID, options) {
        if (!(this instanceof Animate)) return new Animate(elID, options);

        this.el=elID;
        //start doing stuff
        if (!this.el) return;

        if(options)
            this.animate(options);

        var that = this;
        $(this.el).bind("destroy", function() {
            var id = that.el.wmAnimateId;

            if (cache[id]) {
              cache[id] = null;
            }
        });
    };
    Animate.prototype = {
        animationTimer:null,
        isAnimating:false,
        startX:0,
        startY:0,
        runTime:0,
        endX:0,
        endY:0,
        currX:0,
        currY:0,
        animationStartTime:0,
        pauseTime:0,
        completeCB:null,
        easingFn:"linear",
        animateOpts:{},
        updateCb:null,
        animate: function(options) {
            var that=this;
            if(that.isAnimating) return;
            that.isAnimating=true;
            window.cancelAnimationFrame(that.animationTimer);
            if (!options) {
                options={
                    x:0,
                    y:0,
                    duration:0
                };
            }
            this.easingFn=options.easing||"linear";

            this.completeCB=options.complete||null;
            this.updateCB=options.update||null;
            this.runTime=numOnly(options.duration);
            options.complete&&(delete options.complete);
            this.animateOpts=options;
            this.startTime=Date.now();
            this.startMatrix=$.getCssMatrix(this.el);

            if(this.runTime===0)
                this.doAnimate();
        },
        start:function(){
            this.doAnimate();
        },
        doAnimate:function(){
            var now = Date.now(), nextX, nextY,easeStep,that=this;

            if (this.runTime===0||(now >= this.startTime + this.runTime)) {
                that.setPosition(this.animateOpts.x,this.animateOpts.y);
                that.isAnimating = false;
                if(this.updateCB)
                    this.updateCB({x:this.animateOpts.x,y:this.animateOpts.y});
                if(this.completeCB)
                    this.completeCB();
                return;
            }

            now = (now - this.startTime) / this.runTime;
            now=now>1?1:now;
            easeStep = tweens[this.easingFn](now);
            nextX = (this.animateOpts.x - this.startMatrix.e) * easeStep + this.startMatrix.e;
            nextY = (this.animateOpts.y - this.startMatrix.f) * easeStep + this.startMatrix.f;
            this.setPosition(nextX,nextY);
            if(this.updateCB)
                this.updateCB({x:nextX,y:nextY});

            if (this.isAnimating)
                this.animationTimer = window.requestAnimationFrame(function(){that.doAnimate();});
        },
        setPosition:function(x,y){
            this.el.style[$.feat.cssPrefix+"Transform"]="matrix3d( 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, "+x+", "+y+", 0, 1 )";
            this.currX=x;
            this.currY=y;
        },
        stop:function(){
            this.isAnimating=false;
            window.cancelAnimationFrame(this.animationTimer);
            this.pauseTime=Date.now()-this.startTime;
        },
        resume:function(){
            this.isAnimating=true;
            this.startTime=Date.now()-this.pauseTime;
            this.doAnimate();
        }
    };


    var tweens = {
        linear:function (k) {
            return k;
        },
        easeOutSine:function (k) {
            return Math.sin(k * Math.PI / 2 );
        }
    };
    return $;
});