Carousel = Class.create(Abstract, {

    initialize: function (scroller, slides, controls, options) {

        this.scrolling = false;
        this.scroller = scroller;
        this.slides = slides;
        this.controls = controls;

        this.options = Object.extend({ duration: 1.0, frequency: 3, controlClassName: 'carousel-control', jumperClassName: 'carousel-jumper' }, options || {});

        this.slides.each(function (slide, index) {
            slide._index = index;
        });

        this.controls.invoke('observe', 'click', this.click.bind(this));

        if (this.options.auto) {
            this.start();
        }

    },

    click: function (event) {

        this.stop();
        if (this.scrolling) {
            this.scrolling.cancel();
        }

        var element = event.findElement('a');

        if (element.hasClassName(this.options.controlClassName)) {
            eval("this." + element.rel + "()");
        } else if (element.hasClassName(this.options.jumperClassName)) {
            this.moveTo(element, element.rel);
        }

        event.stop();

    },

    moveTo: function (trigger, element) {

        if (this.options.beforeMove && (typeof this.options.beforeMove == 'function')) {
            this.options.beforeMove();
        }

        if (this.options.selectedClassName) {
            this.controls.each((function (elm) { elm.removeClassName(this.options.selectedClassName); }).bind(this));
            trigger.addClassName(this.options.selectedClassName);
        }

        this.previous = this.current ? this.current : this.slides[0];
        this.current = $(element);

        var scrollerOffset = this.scroller.cumulativeOffset();
        var elementOffset = this.current.cumulativeOffset();
        this.scrolling = new Effect.SmoothScroll(this.scroller, { duration: this.options.duration, x: (elementOffset[0] - scrollerOffset[0]), y: (elementOffset[1] - scrollerOffset[1]) });

        if (this.options.afterMove && (typeof this.options.afterMove == 'function')) {
            this.options.afterMove();
        }

        return false;

    },

    prev: function () {
        if (this.current) {
            var currentIndex = this.current._index;
            var prevIndex = (currentIndex == 0) ? this.slides.length - 1 : currentIndex - 1;
        } else {
            var prevIndex = this.slides.length - 1;
        }

        this.moveTo(this.controls[prevIndex], this.slides[prevIndex]);
    },

    next: function () {
        if (this.current) {
            var currentIndex = this.current._index;
            var nextIndex = (this.slides.length - 1 == currentIndex) ? 0 : currentIndex + 1;
        } else {
            var nextIndex = 1;
        }

        this.moveTo(this.controls[nextIndex], this.slides[nextIndex]);
    },

    first: function () {
        var firstIndex = 0;
        if (this.current) {
            var currentIndex = this.current._index;
        }

        this.moveTo(this.controls[firstIndex], this.slides[firstIndex]);
    },

    last: function () {
        var lastIndex = (this.slides.length - 1);
        if (this.current) {
            var currentIndex = this.current._index;
        }

        this.moveTo(this.controls[lastIndex], this.slides[lastIndex]);
    },

    toggle: function () {
        if (this.previous) {
            this.moveTo(this.controls[this.previous._index], this.slides[this.previous._index]);
        } else {
            return false;
        }
    },

    stop: function () { clearTimeout(this.timer); },

    start: function () { this.periodicallyUpdate(); },

    periodicallyUpdate: function () {
        if (this.timer != null) {
            clearTimeout(this.timer);
            this.next();
        }
        this.timer = setTimeout(this.periodicallyUpdate.bind(this), this.options.frequency * 1000);
    }

});

Effect.SmoothScroll = Class.create();

Object.extend(Object.extend(Effect.SmoothScroll.prototype, Effect.Base.prototype), {

    initialize: function (element) {
        this.element = $(element);
        var options = Object.extend({ x: 0, y: 0, mode: 'absolute' }, arguments[1] || {});
        this.start(options);
    },

    setup: function () {
        if (this.options.continuous && !this.element._ext) {
            this.element.cleanWhitespace();
            this.element._ext = true;
            this.element.appendChild(this.element.firstChild);
        }

        this.originalLeft = this.element.scrollLeft;
        this.originalTop = this.element.scrollTop;

        if (this.options.mode == 'absolute') {
            this.options.x -= this.originalLeft;
            this.options.y -= this.originalTop;
        }
    },

    update: function (position) {
        this.element.scrollLeft = this.options.x * position + this.originalLeft;
        this.element.scrollTop = this.options.y * position + this.originalTop;
    }

});