;
(function ($) {
    var transform = (function () {
        var vendors = ['webkit', 'moz', 'ms'];
        var style = document.createElement("div").style;
        var trans = 'transform' in style ? 'transform' : undefined;

        for (var i = 0, count = vendors.length; i < count; i++) {
            var prop = vendors[i] + 'Transform';
            if (prop in style) {
                trans = prop;
                break;
            }
        }

        return trans;
    })();

    var Item = function (element, options) {
        element.item = this;
        this.element = element;

        if (element.tagName === 'IMG') {
            this.fullWidth = element.width;
            this.fullHeight = element.height;
        } else {
            element.style.display = "inline-block";
            this.fullWidth = element.offsetWidth;
            this.fullHeight = element.offsetHeight;
        }

        element.style.position = 'absolute';

        if (options.mirror && this.element.tagName === 'IMG') {
            this.reflection = $(element).reflect(options.mirror).next()[0];

            var $reflection = $(this.reflection);
            this.reflection.fullHeight = $reflection.height();
            $reflection.css('margin-top', options.mirror.gap + 'px');
            $reflection.css('width', '100%');
            element.style.width = "100%";
            this.element = this.element.parentNode;
            this.element.item = this;
            this.element.alt = element.alt;
            this.element.title = element.title;
        }

        if (transform && options.transforms)
            this.element.style[transform + "Origin"] = "0 0";

        this.moveTo = function (x, y, scale) {
            this.width = this.fullWidth * scale;
            this.height = this.fullHeight * scale;
            this.x = x;
            this.y = y;
            this.scale = scale;

            var style = this.element.style;
            style.zIndex = "" + (scale * 100) | 0;

            if (transform && options.transforms) {
                style[transform] = "translate(" + x + "px, " + y + "px) scale(" + scale + ")";
            } else {
                if (options.mirror && this.element.tagName === 'IMG')
                    this.reflection.style.marginTop = (options.mirror.gap * scale) + "px";

                style.width = this.width + "px";
                style.left = x + "px";
                style.top = y + "px";
            }
        }
    }

    var time = !window.performance || !window.performance.now ?
            function () {
                return +new Date()
            } :
            function () {
                return performance.now()
            };

    var cancelFrame = window.cancelAnimationFrame || window.cancelRequestAnimationFrame;
    var requestFrame = window.requestAnimationFrame;

    (function () {
        var vendors = ['webkit', 'moz', 'ms'];

        for (var i = 0, count = vendors.length; i < count && !cancelFrame; i++) {
            cancelFrame = window[vendors[i] + 'CancelAnimationFrame'] || window[vendors[i] + 'CancelRequestAnimationFrame'];
            requestFrame = requestFrame && window[vendors[i] + 'RequestAnimationFrame'];
        }
    }());

    var Carousel = function (element, options) {
        var self = this;
        var $container = $(element);
        this.items = [];
        this.xOrigin = (options.xOrigin === null) ? $container.width() * 0.5 : options.xOrigin;
        this.yOrigin = (options.yOrigin === null) ? $container.height() * 0.1 : options.yOrigin;
        this.xRadius = (options.xRadius === null) ? $container.width() / 2.3 : options.xRadius;
        this.yRadius = (options.yRadius === null) ? $container.height() / 6 : options.yRadius;
        this.farScale = options.farScale;
        this.rotation = this.destRotation = Math.PI / 2; // start with the first item positioned in front
        this.speed = options.speed;
        this.smooth = options.smooth;
        this.fps = options.fps;
        this.timer = 0;
        this.autoPlayAmount = options.autoPlay;
        this.autoPlayDelay = options.autoPlayDelay;
        this.autoPlayTimer = 0;
        this.onLoaded = options.onLoaded;
        this.onRendered = options.onRendered;
        this.onAnimationFinished = options.onAnimationFinished;

        this.itemOptions = {
            transforms: options.transforms
        }

        if (options.mirror) {
            this.itemOptions.mirror = $.extend({gap: 2}, options.mirror);
        }

        $container.css({position: 'relative', overflow: 'hidden'});

        this.renderItem = function (itemIndex, rotation) {
            var item = this.items[itemIndex];
            var sin = Math.sin(rotation);
            var farScale = this.farScale;
            var scale = farScale + ((1 - farScale) * (sin + 1) * 0.5);

            item.moveTo(
                    this.xOrigin + (scale * ((Math.cos(rotation) * this.xRadius) - (item.fullWidth * 0.5))),
                    this.yOrigin + (scale * sin * this.yRadius),
                    scale
                    );
        }

        this.render = function () {
            var count = this.items.length;
            var spacing = 2 * Math.PI / count;
            var radians = this.rotation;

            for (var i = 0; i < count; i++) {
                this.renderItem(i, radians);
                radians += spacing;
            }

            if (typeof this.onRendered === 'function')
                this.onRendered(this);
        }

        this.playFrame = function () {
            var rem = self.destRotation - self.rotation;
            var now = time();
            var dt = (now - self.lastTime) * 0.002;
            self.lastTime = now;

            if (Math.abs(rem) < 0.003) {
                self.rotation = self.destRotation;
                self.pause();

                if (typeof self.onAnimationFinished === 'function')
                    self.onAnimationFinished();
            } else {
                // Rotate asymptotically closer to the destination
                self.rotation = self.destRotation - rem / (1 + (self.speed * dt));
                self.scheduleNextFrame();
            }

            self.render();
        }

        this.scheduleNextFrame = function () {
            this.lastTime = time();

            this.timer = this.smooth && cancelFrame ?
                    requestFrame(self.playFrame) :
                    setTimeout(self.playFrame, 1000 / this.fps);
        }

        this.itemsRotated = function () {
            return this.items.length * ((Math.PI / 2) - this.rotation) / (2 * Math.PI);
        }

        this.floatIndex = function () {
            var count = this.items.length;
            var floatIndex = this.itemsRotated() % count;

            // Make sure float-index is positive
            return (floatIndex < 0) ? floatIndex + count : floatIndex;
        }

        this.nearestIndex = function () {
            return Math.round(this.floatIndex()) % this.items.length;
        }

        this.nearestItem = function () {
            return this.items[this.nearestIndex()];
        }

        this.play = function () {
            if (this.timer === 0)
                this.scheduleNextFrame();
        }

        this.pause = function () {
            this.smooth && cancelFrame ? cancelFrame(this.timer) : clearTimeout(this.timer);
            this.timer = 0;
        }

        this.go = function (count) {
            this.destRotation += (2 * Math.PI / this.items.length) * count;
            this.play();
        }

        this.deactivate = function () {
            this.pause();
            clearInterval(this.autoPlayTimer);
            if (options.buttonLeft)
                options.buttonLeft.unbind('click');
            if (options.buttonRight)
                options.buttonRight.unbind('click');
            $container.unbind('.cloud9');
        }

        this.autoPlay = function () {
            this.autoPlayTimer = setInterval(
                    function () {
                        self.go(self.autoPlayAmount)
                    },
                    this.autoPlayDelay
                    );
        }

        this.enableAutoPlay = function () {
            // Stop auto-play on mouse over
            $container.bind('mouseover.cloud9', function () {
                clearInterval(self.autoPlayTimer);
            });

            // Resume auto-play when mouse leaves the container
            $container.bind('mouseout.cloud9', function () {
                self.autoPlay();
            });

            this.autoPlay();
        }

        this.bindControls = function () {
            if (options.buttonLeft) {
                options.buttonLeft.bind('click', function () {
                    self.go(-1);
                    return false;
                });
            }

            if (options.buttonRight) {
                options.buttonRight.bind('click', function () {
                    self.go(1);
                    return false;
                });
            }

            if (options.mouseWheel) {
                $container.bind('mousewheel.cloud9', function (event, delta) {
                    self.go((delta > 0) ? 1 : -1);
                    return false;
                });
            }

            if (options.bringToFront) {
                $container.bind('click.cloud9', function (event) {
                    var hits = $(event.target).closest('.' + options.itemClass);

                    if (hits.length !== 0) {
                        var idx = self.items.indexOf(hits[0].item);
                        var count = self.items.length;
                        var diff = idx - (self.floatIndex() % count);
                        if (2 * Math.abs(diff) > count)
                            diff += (diff > 0) ? -count : count;
                        if (Math.abs(diff) > 0.5)
                            event.preventDefault();
                        self.destRotation = self.rotation;
                        self.go(-diff);
                    }
                });
            }
        }

        var items = $container.find('.' + options.itemClass);

        this.finishInit = function () {
            for (var i = 0; i < items.length; i++) {
                var item = items[i];
                if ((item.tagName === 'IMG') &&
                        ((item.width === undefined) || ((item.complete !== undefined) && !item.complete)))
                    return;
            }

            clearInterval(this.initTimer);

            // Init items
            for (i = 0; i < items.length; i++)
                this.items.push(new Item(items[i], this.itemOptions));

            // Disable click-dragging of items
            $container.bind('mousedown onselectstart', function () {
                return false
            });

            if (this.autoPlayAmount !== 0)
                this.enableAutoPlay();
            this.bindControls();
            this.render();

            if (typeof this.onLoaded === 'function')
                this.onLoaded(this);
        };

        this.initTimer = setInterval(function () {
            self.finishInit()
        }, 50);
    }

    //
    // The jQuery plugin
    //
    $.fn.CoverCarousel = function (options) {
        return this.each(function () {
            options = $.extend({
                xOrigin: null, // null: calculated automatically
                yOrigin: null,
                xRadius: null,
                yRadius: null,
                farScale: 0.5, // scale of the farthest item
                transforms: true, // enable CSS transforms
                smooth: true, // enable smooth animation via requestAnimationFrame()
                fps: 30, // fixed frames per second (if smooth animation is off)
                speed: 4, // positive number
                autoPlay: 0, // [ 0: off | number of items (integer recommended, positive is clockwise) ]
                autoPlayDelay: 4000,
                bringToFront: false,
                itemClass: 'cloud9-item',
                handle: 'carousel'
            }, options);

            $(this).data(options.handle, new Carousel(this, options));
        });
    }
})(window.jQuery || window.Zepto);