YUI.add('transition', function (Y, NAME) {

/**

* Provides the transition method for Node.

* Transition has no API of its own, but adds the transition method to Node.

*

* @module transition

* @requires node-style

*/

var CAMEL_VENDOR_PREFIX = '',

    VENDOR_PREFIX = '',

    DOCUMENT = Y.config.doc,

    DOCUMENT_ELEMENT = 'documentElement',

    DOCUMENT_STYLE = DOCUMENT[DOCUMENT_ELEMENT].style,

    TRANSITION_CAMEL = 'transition',

    TRANSITION_PROPERTY_CAMEL = 'transitionProperty',

    TRANSITION_PROPERTY,

    TRANSITION_DURATION,

    TRANSITION_TIMING_FUNCTION,

    TRANSITION_DELAY,

    TRANSITION_END,

    ON_TRANSITION_END,

    EMPTY_OBJ = {},

    VENDORS = [

        'Webkit',

        'Moz'

    ],

    VENDOR_TRANSITION_END = {

        Webkit: 'webkitTransitionEnd'

    },

/**

 * A class for constructing transition instances.

 * Adds the "transition" method to Node.

 * @class Transition

 * @constructor

 */

Transition = function() {

    this.init.apply(this, arguments);

};

// One off handling of transform-prefixing.

Transition._TRANSFORM = 'transform';

Transition._toCamel = function(property) {

    property = property.replace(/-([a-z])/gi, function(m0, m1) {

        return m1.toUpperCase();

    });

    return property;

};

Transition._toHyphen = function(property) {

    property = property.replace(/([A-Z]?)([a-z]+)([A-Z]?)/g, function(m0, m1, m2, m3) {

        var str = ((m1) ? '-' + m1.toLowerCase() : '') + m2;

        if (m3) {

            str += '-' + m3.toLowerCase();

        }

        return str;

    });

    return property;

};

Transition.SHOW_TRANSITION = 'fadeIn';

Transition.HIDE_TRANSITION = 'fadeOut';

Transition.useNative = false;

// Map transition properties to vendor-specific versions.

if ('transition' in DOCUMENT_STYLE

    && 'transitionProperty' in DOCUMENT_STYLE

    && 'transitionDuration' in DOCUMENT_STYLE

    && 'transitionTimingFunction' in DOCUMENT_STYLE

    && 'transitionDelay' in DOCUMENT_STYLE) {

    Transition.useNative = true;

    Transition.supported = true; // TODO: remove

} else {

    Y.Array.each(VENDORS, function(val) { // then vendor specific

        var property = val + 'Transition';

        if (property in DOCUMENT[DOCUMENT_ELEMENT].style) {

            CAMEL_VENDOR_PREFIX = val;

            VENDOR_PREFIX       = Transition._toHyphen(val) + '-';

            Transition.useNative = true;

            Transition.supported = true; // TODO: remove

            Transition._VENDOR_PREFIX = val;

        }

    });

}

// Map transform property to vendor-specific versions.

// One-off required for cssText injection.

if (typeof DOCUMENT_STYLE.transform === 'undefined') {

    Y.Array.each(VENDORS, function(val) { // then vendor specific

        var property = val + 'Transform';

        if (typeof DOCUMENT_STYLE[property] !== 'undefined') {

            Transition._TRANSFORM = property;

        }

    });

}

if (CAMEL_VENDOR_PREFIX) {

    TRANSITION_CAMEL          = CAMEL_VENDOR_PREFIX + 'Transition';

    TRANSITION_PROPERTY_CAMEL = CAMEL_VENDOR_PREFIX + 'TransitionProperty';

}

TRANSITION_PROPERTY        = VENDOR_PREFIX + 'transition-property';

TRANSITION_DURATION        = VENDOR_PREFIX + 'transition-duration';

TRANSITION_TIMING_FUNCTION = VENDOR_PREFIX + 'transition-timing-function';

TRANSITION_DELAY           = VENDOR_PREFIX + 'transition-delay';

TRANSITION_END    = 'transitionend';

ON_TRANSITION_END = 'on' + CAMEL_VENDOR_PREFIX.toLowerCase() + 'transitionend';

TRANSITION_END    = VENDOR_TRANSITION_END[CAMEL_VENDOR_PREFIX] || TRANSITION_END;

Transition.fx = {};

Transition.toggles = {};

Transition._hasEnd = {};

Transition._reKeywords = /^(?:node|duration|iterations|easing|delay|on|onstart|onend)$/i;

Y.Node.DOM_EVENTS[TRANSITION_END] = 1;

Transition.NAME = 'transition';

Transition.DEFAULT_EASING = 'ease';

Transition.DEFAULT_DURATION = 0.5;

Transition.DEFAULT_DELAY = 0;

Transition._nodeAttrs = {};

Transition.prototype = {

    constructor: Transition,

    init: function(node, config) {

        var anim = this;

        anim._node = node;

        if (!anim._running && config) {

            anim._config = config;

            node._transition = anim; // cache for reuse

            anim._duration = ('duration' in config) ?

                config.duration: anim.constructor.DEFAULT_DURATION;

            anim._delay = ('delay' in config) ?

                config.delay: anim.constructor.DEFAULT_DELAY;

            anim._easing = config.easing || anim.constructor.DEFAULT_EASING;

            anim._count = 0; // track number of animated properties

            anim._running = false;

        }

        return anim;

    },

    addProperty: function(prop, config) {

        var anim = this,

            node = this._node,

            uid = Y.stamp(node),

            nodeInstance = Y.one(node),

            attrs = Transition._nodeAttrs[uid],

            computed,

            compareVal,

            dur,

            attr,

            val;

        if (!attrs) {

            attrs = Transition._nodeAttrs[uid] = {};

        }

        attr = attrs[prop];

        // might just be a value

        if (config && config.value !== undefined) {

            val = config.value;

        } else if (config !== undefined) {

            val = config;

            config = EMPTY_OBJ;

        }

        if (typeof val === 'function') {

            val = val.call(nodeInstance, nodeInstance);

        }

        if (attr && attr.transition) {

            // take control if another transition owns this property

            if (attr.transition !== anim) {

                attr.transition._count--; // remapping attr to this transition

            }

        }

        anim._count++; // properties per transition

        // make 0 async and fire events

        dur = ((typeof config.duration !== 'undefined') ? config.duration :

                    anim._duration) || 0.0001;

        attrs[prop] = {

            value: val,

            duration: dur,

            delay: (typeof config.delay !== 'undefined') ? config.delay :

                    anim._delay,

            easing: config.easing || anim._easing,

            transition: anim

        };

        // native end event doesnt fire when setting to same value

        // supplementing with timer

        // val may be a string or number (height: 0, etc), but computedStyle is always string

        computed = Y.DOM.getComputedStyle(node, prop);

        compareVal = (typeof val === 'string') ? computed : parseFloat(computed);

        if (Transition.useNative && compareVal === val) {

            setTimeout(function() {

                anim._onNativeEnd.call(node, {

                    propertyName: prop,

                    elapsedTime: dur

                });

            }, dur * 1000);

        }

    },

    removeProperty: function(prop) {

        var anim = this,

            attrs = Transition._nodeAttrs[Y.stamp(anim._node)];

        if (attrs && attrs[prop]) {

            delete attrs[prop];

            anim._count--;

        }

    },

    initAttrs: function(config) {

        var attr,

            node = this._node;

        if (config.transform && !config[Transition._TRANSFORM]) {

            config[Transition._TRANSFORM] = config.transform;

            delete config.transform; // TODO: copy

        }

        for (attr in config) {

            if (config.hasOwnProperty(attr) && !Transition._reKeywords.test(attr)) {

                this.addProperty(attr, config[attr]);

                // when size is auto or % webkit starts from zero instead of computed

                // (https://bugs.webkit.org/show_bug.cgi?id=16020)

                // TODO: selective set

                if (node.style[attr] === '') {

                    Y.DOM.setStyle(node, attr, Y.DOM.getComputedStyle(node, attr));

                }

            }

        }

    },

    /**

     * Starts or an animation.

     * @method run

     * @chainable

     * @private

     */

    run: function(callback) {

        var anim = this,

            node = anim._node,

            config = anim._config,

            data = {

                type: 'transition:start',

                config: config

            };

        if (!anim._running) {

            anim._running = true;

            if (config.on && config.on.start) {

                config.on.start.call(Y.one(node), data);

            }

            anim.initAttrs(anim._config);

            anim._callback = callback;

            anim._start();

        }

        return anim;

    },

    _start: function() {

        this._runNative();

    },

    _prepDur: function(dur) {

        dur = parseFloat(dur) * 1000;

        return dur + 'ms';

    },

    _runNative: function() {

        var anim = this,

            node = anim._node,

            uid = Y.stamp(node),

            style = node.style,

            computed = node.ownerDocument.defaultView.getComputedStyle(node),

            attrs = Transition._nodeAttrs[uid],

            cssText = '',

            cssTransition = computed[Transition._toCamel(TRANSITION_PROPERTY)],

            transitionText = TRANSITION_PROPERTY + ': ',

            duration = TRANSITION_DURATION + ': ',

            easing = TRANSITION_TIMING_FUNCTION + ': ',

            delay = TRANSITION_DELAY + ': ',

            hyphy,

            attr,

            name;

        // preserve existing transitions

        if (cssTransition !== 'all') {

            transitionText += cssTransition + ',';

            duration += computed[Transition._toCamel(TRANSITION_DURATION)] + ',';

            easing += computed[Transition._toCamel(TRANSITION_TIMING_FUNCTION)] + ',';

            delay += computed[Transition._toCamel(TRANSITION_DELAY)] + ',';

        }

        // run transitions mapped to this instance

        for (name in attrs) {

            hyphy = Transition._toHyphen(name);

            attr = attrs[name];

            if ((attr = attrs[name]) && attr.transition === anim) {

                if (name in node.style) { // only native styles allowed

                    duration += anim._prepDur(attr.duration) + ',';

                    delay += anim._prepDur(attr.delay) + ',';

                    easing += (attr.easing) + ',';

                    transitionText += hyphy + ',';

                    cssText += hyphy + ': ' + attr.value + '; ';

                } else {

                    this.removeProperty(name);

                }

            }

        }

        transitionText = transitionText.replace(/,$/, ';');

        duration = duration.replace(/,$/, ';');

        easing = easing.replace(/,$/, ';');

        delay = delay.replace(/,$/, ';');

        // only one native end event per node

        if (!Transition._hasEnd[uid]) {

            node.addEventListener(TRANSITION_END, anim._onNativeEnd, '');

            Transition._hasEnd[uid] = true;

        }

        style.cssText += transitionText + duration + easing + delay + cssText;