/**
 * @fileOverview
 * @author: wehr
 * @date: 15.09.11
 *
 *
 */
neo.namespace("neo.jsComponents.Homepage");
/**
 * Homepage components class
 * @class Homepage components class
 * @constructs
 * @param {Object} element Dom element representing the component container
 * @param {index} index the index, normally a uid referencing this component
 */
neo.jsComponents.Homepage = function (element, index) {
    //the components constructor, do magic in here!
    /**
     * @type {jQuery}
     */
    this._$container = $(element);
    this._$currentItem = $([]);
    this._id = index;
    this._current = null;
    this._slideshowTimer = 0;
    this._weights = [];
};

neo.jsComponents.Homepage.prototype = {
    _bindNavigation:function () {
        this._$nav.children('ul').children('li').hover(function () {
            $(this).children('div').fadeIn(300, "easeOutQuart");
        }, function () {
            $(this).children('div').fadeOut(300, "easeInQuart");
        });
    },
    _binHovering:function () {
        var _this = this;
        this._$stages.delegate('.description', 'mouseenter',
            function () {
                clearTimeout(_this._slideshowTimer);
            }).delegate('.description', 'mouseleave', function () {
                _this._slideshow();
            });
    },
    /**
     * Get the next item randomly  (http://stackoverflow.com/questions/1761626/weighted-random-numbers)
     * See this jsfiddle http://jsfiddle.net/GhLDu/1/, it works ;)
     * @return {*}
     * @private
     */
    _getNext:function () {
        var weights = this._weights,
            i = 0,
            sum = 0,
            l,
            rand,
            resultIndex;
        //remove the current index, we don't want it to be choosen
        if (this._current !== null) {
            weights = this._weights.slice(0, this._current).concat(this._weights.slice(this._current+1));
        }
        //now, get the sum of all weights
        for (i, l = weights.length; i < l; i += 1) {
            sum += weights[i].weight;
        }
        //get a random number in the sum's range
        rand = Math.floor(Math.random() * sum);
        //iterate over all elements, one by one, the sorting doesn't matter
        for (i = 0; i < l; i += 1) {
            //and look, if the random number from above is smaller than the current element's weight
            if (rand < weights[i].weight && weights[i].index !== this._current) {
                //if so, here we have our randomly selected element
                resultIndex = weights[i].index;
                //so let's get out of this loop
                break;
            } else {
                //if not, subtract the current element's weight from the random number and continue
                rand -= weights[i].weight;
            }
        }
        return resultIndex;
    },
    _preload:function (index) {
        var _this = this;
        this._blocker.block();
        this._$stages.eq(index).imagesLoaded(function () {
            _this._blocker.unblock(0);
            _this._showStage(index);
        });
    },
    _slideshow:function () {
        var _this = this;
        if (isNumber(this._interval)) {
            this._slideshowTimer = window.setTimeout(function () {
                _this._preload(_this._getNext());
            }, this._interval + 1600);
        }
    },
    _showStage:function (index) {
        var _this = this, $newDesc;
        if (index >= 0 && index < this._$stages.length) {
            this._current = index;
            this._$currentItem.children('.description').animate({
                top:0
            }, 450, "easeInQuart", function () {
                this.style.top = neo.jsComponents.Homepage.STAGE_HEIGHT + "px";
            });
            this._$currentItem.delay(300).fadeOut(1200);
            this._$currentItem = this._$stages.eq(index);
            $newDesc = this._$currentItem.children('.description');
            $newDesc.delay(800).animate({
                top:$newDesc.data("topDistance")
            }, 800, "easeOutQuart");
            this._$currentItem.fadeIn(1600, "easeOutSine");
            this._$nav.find('ul li.current').removeClass("current");
            this._$stage.css({
                backgroundColor:this._$currentItem.data("bgColor")
            });
            $(this._$currentItem.data('nav')).addClass("current");
            this._slideshow();
        } else if (index >= this._$stages.length) {
            this._showStage(0);
        }
    },
    /**
     * Loads the Homepage class
     */
    load:function () {
        var _this = this,
            blocker,
            $desc;
        this._$nav = this._$container.children('.home-navigation');
        this._$stage = this._$container.children('.home-stage');
        this._$stages = this._$stage.find('.stage-item');
        this._$stages.each(function (index) {
            var weight = parseInt(this.getAttribute("data-random-weight"), 10);
            if (typeof(weight)=="number" && weight+""=="NaN") {
                weight = 10;
            }
            _this._weights.push({
                index:index,
                weight:weight });
              
        });
        /*
        Inline unit test :-p
        var t = "";
        for (var i = 0;i<10000;i++){
            var n = this._getNext();
            if (n === this._current){
                throw "arghh "
            }
            this._current = n;
            t+=","+this._current;
        }
        console.log(t);*/
        this._interval = this._$stage.data("slideshowInterval") * 1000;
        this._blocker = new neo.ui.UiBlocker(this._$stage);
        this._$stages.children('.description').each(function () {
            $desc = $(this);
            $desc.data("topDistance", this.style.top).css({top:neo.jsComponents.Homepage.STAGE_HEIGHT});
        });
        this._preload(this._getNext());
        this._bindNavigation();
        this._binHovering();
    },
    /**
     * unloads the Homepage class
     */
    unload:function () {
        //do something
    },
    /**
     * Suspend/pause the component
     */
    suspend:function () {
    },
    /**
     * Resume the component
     */
    resume:function () {
    }
};
neo.jsComponents.Homepage.INITIAL_STAGE = 0;
neo.jsComponents.Homepage.STAGE_HEIGHT = 544;