/*
---
description: Simple image crossfade plugin

license: MIT-style

authors:
- Trae Robrock

requires:
- core/1.3: '*'

provides: [Crossfade]

...
*/

var Crossfade = new Class({
    Implements: [Options, Chain],
    options: {
        duration: 1000
    },

    initialize: function(element, options) {
        this.setOptions(options);
        this.element = element;
        this.currentIndex = 0;
        this.images = element.getChildren();
        for (var i = 0; i < this.images.length; i++) {
            if (i in this.images) {
                this.images[i].setStyles({ top: 0, left: 0, position: "absolute" });
                this.images[i].set('tween', { duration: this.options.duration });
                if (i !== 0) { this.images[i].fade('hide'); }
            }
        }
    },

    start: function() {
        this.timer = setInterval(this.next.bind(this), 5000);
    },

    next: function() {
        var currentImage = this.images[this.currentIndex],
        nextIndex = (this.currentIndex + 1 == this.images.length) ? 0 : this.currentIndex + 1;
        nextImage = this.images[nextIndex];

        this.chain(
      function() { this.hide(currentImage); } .bind(this),
      function() { this.show(nextImage); } .bind(this)
    );
        this.callChain();

        this.currentIndex = nextIndex;
    },

    show: function(image) {
        image.setStyle('z-index', 100);
        image.fade('in');
    },

    hide: function(image) {
        setTimeout(this.callChain.bind(this), this.options.duration / 4);
        image.setStyle('z-index', 0);
        image.fade('out');
    }
});