/**
 *
 * Spacegallery
 * Author: Stefan Petre www.eyecon.ro
 *
 */

(function($){
        EYE.extend({

                spacegallery: {

                        //default options (many options are controled via CSS)
                        defaults: {
                                border: 0, // border arround the image
                                perspective: 140, // perpective height
                                minScale: 0.2, // minimum scale for the image in the back
                                duration: 1000, // aimation duration
                                loadingClass: null, // CSS class applied to the element while looading images
                                before: function(){return false},
                                after: function(){return false}
                        },

                        animated: false,

                        //position images
                        positionImages: function(el) {
                                var top = 0;
                                EYE.spacegallery.animated = false;
                                $(el)
                                        .find('a')
                                                .removeClass(el.spacegalleryCfg.loadingClass)
                                                .end()
                                        .find('img')
                                                .removeAttr('height')
                                                .each(function(nr){
                                                        var newWidth = this.spacegallery.origWidth - (this.spacegallery.origWidth - this.spacegallery.origWidth * el.spacegalleryCfg.minScale) * el.spacegalleryCfg.asins[nr];
                                                        $(this)
                                                                .css({
                                                                        top: el.spacegalleryCfg.tops[nr] + 'px',
                                                                        marginLeft: - parseInt((newWidth + el.spacegalleryCfg.border)/2, 10) + 'px',
                                                                        opacity: 1 - el.spacegalleryCfg.asins[nr]
                                                                })
                                                                .attr('width', parseInt(newWidth));
                                                        this.spacegallery.next = el.spacegalleryCfg.asins[nr+1];
                                                        this.spacegallery.nextTop = el.spacegalleryCfg.tops[nr+1] - el.spacegalleryCfg.tops[nr];
                                                        this.spacegallery.origTop = el.spacegalleryCfg.tops[nr];
                                                        this.spacegallery.opacity = 1 - el.spacegalleryCfg.asins[nr];
                                                        this.spacegallery.increment = el.spacegalleryCfg.asins[nr] - this.spacegallery.next;
                                                        this.spacegallery.current = el.spacegalleryCfg.asins[nr];
                                                        this.spacegallery.width = newWidth;
                                                })
                        },

                        //animate to nex image
                        next: function(e) {
                                if (EYE.spacegallery.animated === false) {
                                        EYE.spacegallery.animated = true;
                                        var el = this.parentNode;
                                        el.spacegalleryCfg.before.apply(el);
                                        $(el)
                                                .css('spacegallery', 0)
                                                .animate({
                                                        spacegallery: 100
                                                },{
                                                        easing: 'easeOut',
                                                        duration: el.spacegalleryCfg.duration,
                                                        complete: function() {
                                                                $(el)
                                                                        .find('img:last')
                                                                        .prependTo(el);
                                                                EYE.spacegallery.positionImages(el);
                                                                el.spacegalleryCfg.after.apply(el);
                                                        },
                                                        step: function(now) {
                                                                $('img', this)
                                                                        .each(function(nr){
                                                                                var newWidth, top, next;
                                                                                if (nr + 1 == el.spacegalleryCfg.images) {
                                                                                        top = this.spacegallery.origTop + this.spacegallery.nextTop * 4 * now /100;
                                                                                        newWidth = this.spacegallery.width * top / this.spacegallery.origTop;
                                                                                        $(this)
                                                                                                .css({
                                                                                                        top: top + 'px',
                                                                                                        opacity: 0.7 - now/100,
                                                                                                        marginLeft: - parseInt((newWidth + el.spacegalleryCfg.border)/2, 10) + 'px'
                                                                                                })
                                                                                                .attr('width', newWidth);
                                                                                } else {
                                                                                        next = this.spacegallery.current - this.spacegallery.increment * now /100;
                                                                                        newWidth = this.spacegallery.origWidth - (this.spacegallery.origWidth - this.spacegallery.origWidth * el.spacegalleryCfg.minScale) * next;
                                                                                        $(this).css({
                                                                                                top: this.spacegallery.origTop + this.spacegallery.nextTop * now /100 + 'px',
                                                                                                opacity: 1 - next,
                                                                                                marginLeft: - parseInt((newWidth + el.spacegalleryCfg.border)/2, 10) + 'px'
                                                                                        })
                                                                                        .attr('width', newWidth);
                                                                                }
                                                                        });
                                                        }
                                                });
                                }

                                this.blur();
                                return false;
                        },

                        //constructor
                        init: function(opt) {
                                opt = $.extend({}, EYE.spacegallery.defaults, opt||{});
                                return this.each(function(){
                                        var el = this;
                                        if ($(el).is('.spacegallery')) {
                                                $('<a href="#"></a>')
                                                        .appendTo(this)
                                                        .addClass(opt.loadingClass)
                                                        .bind('click', EYE.spacegallery.next);
                                                el.spacegalleryCfg = opt;
                                                el.spacegalleryCfg.images = el.getElementsByTagName('img').length;
                                                el.spacegalleryCfg.loaded = 0;
                                                el.spacegalleryCfg.asin = Math.asin(1);
                                                el.spacegalleryCfg.asins = {};
                                                el.spacegalleryCfg.tops = {};
                                                el.spacegalleryCfg.increment = parseInt(el.spacegalleryCfg.perspective/el.spacegalleryCfg.images, 10);
                                                var top = 0;
                                                $('img', el)
                                                        .each(function(nr){
                                                                var imgEl = new Image();
                                                                var elImg = this;
                                                                el.spacegalleryCfg.asins[nr] = 1 - Math.asin((nr+1)/el.spacegalleryCfg.images)/el.spacegalleryCfg.asin;
                                                                top += el.spacegalleryCfg.increment - el.spacegalleryCfg.increment * el.spacegalleryCfg.asins[nr];
                                                                el.spacegalleryCfg.tops[nr] = top;
                                                                elImg.spacegallery = {};
                                                                imgEl.src = this.src;
                                                                if (imgEl.complete) {
                                                                        el.spacegalleryCfg.loaded ++;
                                                                        elImg.spacegallery.origWidth = imgEl.width;
                                                                        elImg.spacegallery.origHeight = imgEl.height
                                                                } else {
                                                                        imgEl.onload = function() {
                                                                                el.spacegalleryCfg.loaded ++;
                                                                                elImg.spacegallery.origWidth = imgEl.width;
                                                                                elImg.spacegallery.origHeight = imgEl.height
                                                                                if (el.spacegalleryCfg.loaded == el.spacegalleryCfg.images) {

                                                                                        EYE.spacegallery.positionImages(el);
                                                                                }
                                                                        };
                                                                }
                                                        });
                                                el.spacegalleryCfg.asins[el.spacegalleryCfg.images] = el.spacegalleryCfg.asins[el.spacegalleryCfg.images - 1] * 1.3;
                                                el.spacegalleryCfg.tops[el.spacegalleryCfg.images] = el.spacegalleryCfg.tops[el.spacegalleryCfg.images - 1] * 1.3;
                                                if (el.spacegalleryCfg.loaded == el.spacegalleryCfg.images) {
                                                        EYE.spacegallery.positionImages(el);
                                                }
                                        }
                                });
                        }
                }
        });

        $.fn.extend({

                /**
                 * Create a space gallery
                 * @name spacegallery
                 * @description create a space gallery
                 * @option        int                        border                        Images' border. Default: 6
                 * @option        int                        perspective                Perpective height. Default: 140
                 * @option        float                minScale                Minimum scale for the image in the back. Default: 0.2
                 * @option        int                        duration                Animation duration. Default: 800
                 * @option        string                loadingClass        CSS class applied to the element while looading images. Default: null
                 * @option        function        before                        Callback function triggered before going to the next image
                 * @option        function        after                        Callback function triggered after going to the next image
                 */
                spacegallery: EYE.spacegallery.init
        });
        $.extend($.easing,{
                easeOut:function (x, t, b, c, d) {
                        return -c *(t/=d)*(t-2) + b;
                }
        });
})(jQuery);