src/cm/media/js/lib/yui/yui3.0.0/build/attribute/attribute.js
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     1 /*
       
     2 Copyright (c) 2009, Yahoo! Inc. All rights reserved.
       
     3 Code licensed under the BSD License:
       
     4 http://developer.yahoo.net/yui/license.txt
       
     5 version: 3.0.0
       
     6 build: 1549
       
     7 */
       
     8 YUI.add('attribute-base', function(Y) {
       
     9 
       
    10     /**
       
    11      * The State class maintains state for a collection of named items, with 
       
    12      * a varying number of properties defined.
       
    13      *
       
    14      * It avoids the need to create a separate class for the item, and separate instances 
       
    15      * of these classes for each item, by storing the state in a 2 level hash table, 
       
    16      * improving performance when the number of items is likely to be large.
       
    17      *
       
    18      * @constructor
       
    19      * @class State
       
    20      */
       
    21     Y.State = function() { 
       
    22         /**
       
    23          * Hash of attributes
       
    24          * @property data
       
    25          */
       
    26         this.data = {};
       
    27     };
       
    28 
       
    29     Y.State.prototype = {
       
    30 
       
    31         /**
       
    32          * Adds a property to an item.
       
    33          *
       
    34          * @method add
       
    35          * @param name {String} The name of the item.
       
    36          * @param key {String} The name of the property.
       
    37          * @param val {Any} The value of the property.
       
    38          */
       
    39         add : function(name, key, val) {
       
    40             var d = this.data;
       
    41             d[key] = d[key] || {};
       
    42             d[key][name] = val;
       
    43         },
       
    44 
       
    45         /**
       
    46          * Adds multiple properties to an item.
       
    47          *
       
    48          * @method addAll
       
    49          * @param name {String} The name of the item.
       
    50          * @param o {Object} A hash of property/value pairs.
       
    51          */
       
    52         addAll: function(name, o) {
       
    53             var key;
       
    54             for (key in o) {
       
    55                 if (o.hasOwnProperty(key)) {
       
    56                     this.add(name, key, o[key]);
       
    57                 }
       
    58             }
       
    59         },
       
    60 
       
    61         /**
       
    62          * Removes a property from an item.
       
    63          *
       
    64          * @method remove
       
    65          * @param name {String} The name of the item.
       
    66          * @param key {String} The property to remove.
       
    67          */
       
    68         remove: function(name, key) {
       
    69             var d = this.data;
       
    70             if (d[key] && (name in d[key])) {
       
    71                 delete d[key][name];
       
    72             }
       
    73         },
       
    74 
       
    75         /**
       
    76          * Removes multiple properties from an item, or remove the item completely.
       
    77          *
       
    78          * @method removeAll
       
    79          * @param name {String} The name of the item.
       
    80          * @param o {Object|Array} Collection of properties to delete. If not provided, the entire item is removed.
       
    81          */
       
    82         removeAll: function(name, o) {
       
    83             var d = this.data;
       
    84 
       
    85             Y.each(o || d, function(v, k) {
       
    86                 if(Y.Lang.isString(k)) {
       
    87                     this.remove(name, k);
       
    88                 } else {
       
    89                     this.remove(name, v);
       
    90                 }
       
    91             }, this);
       
    92         },
       
    93 
       
    94         /**
       
    95          * For a given item, returns the value of the property requested, or undefined if not found.
       
    96          *
       
    97          * @method get
       
    98          * @param name {String} The name of the item
       
    99          * @param key {String} Optional. The property value to retrieve.
       
   100          * @return {Any} The value of the supplied property.
       
   101          */
       
   102         get: function(name, key) {
       
   103             var d = this.data;
       
   104             return (d[key] && name in d[key]) ?  d[key][name] : undefined;
       
   105         },
       
   106 
       
   107         /**
       
   108          * For the given item, returns a disposable object with all of the
       
   109          * item's property/value pairs.
       
   110          *
       
   111          * @method getAll
       
   112          * @param name {String} The name of the item
       
   113          * @return {Object} An object with property/value pairs for the item.
       
   114          */
       
   115         getAll : function(name) {
       
   116             var d = this.data, o;
       
   117 
       
   118             Y.each(d, function(v, k) {
       
   119                 if (name in d[k]) {
       
   120                     o = o || {};
       
   121                     o[k] = v[name];
       
   122                 }
       
   123             }, this);
       
   124 
       
   125             return o;
       
   126         }
       
   127     };
       
   128     /**
       
   129      * The attribute module provides an augmentable Attribute implementation, which 
       
   130      * adds configurable attributes and attribute change events to the class being 
       
   131      * augmented. It also provides a State class, which is used internally by Attribute,
       
   132      * but can also be used independently to provide a name/property/value data structure to
       
   133      * store state.
       
   134      *
       
   135      * @module attribute
       
   136      */
       
   137 
       
   138     /**
       
   139      * The attribute-base submodule provides core attribute handling support, with everything
       
   140      * aside from complex attribute handling in the provider's constructor.
       
   141      *
       
   142      * @module attribute
       
   143      * @submodule attribute-base
       
   144      */
       
   145     var O = Y.Object,
       
   146         Lang = Y.Lang,
       
   147         EventTarget = Y.EventTarget,
       
   148 
       
   149         DOT = ".",
       
   150         CHANGE = "Change",
       
   151 
       
   152         // Externally configurable props
       
   153         GETTER = "getter",
       
   154         SETTER = "setter",
       
   155         READ_ONLY = "readOnly",
       
   156         WRITE_ONCE = "writeOnce",
       
   157         VALIDATOR = "validator",
       
   158         VALUE = "value",
       
   159         VALUE_FN = "valueFn",
       
   160         BROADCAST = "broadcast",
       
   161         LAZY_ADD = "lazyAdd",
       
   162         BYPASS_PROXY = "_bypassProxy",
       
   163 
       
   164         // Used for internal state management
       
   165         ADDED = "added",
       
   166         INITIALIZING = "initializing",
       
   167         INIT_VALUE = "initValue",
       
   168         PUBLISHED = "published",
       
   169         DEF_VALUE = "defaultValue",
       
   170         LAZY = "lazy",
       
   171         IS_LAZY_ADD = "isLazyAdd",
       
   172 
       
   173         INVALID_VALUE,
       
   174         MODIFIABLE = {};
       
   175 
       
   176         // Properties which can be changed after the attribute has been added.
       
   177         MODIFIABLE[READ_ONLY] = 1;
       
   178         MODIFIABLE[WRITE_ONCE] = 1;
       
   179         MODIFIABLE[GETTER] = 1;
       
   180         MODIFIABLE[BROADCAST] = 1;
       
   181 
       
   182     /**
       
   183      * <p>
       
   184      * Attribute provides configurable attribute support along with attribute change events. It is designed to be 
       
   185      * augmented on to a host class, and provides the host with the ability to configure attributes to store and retrieve state, 
       
   186      * along with attribute change events.
       
   187      * </p>
       
   188      * <p>For example, attributes added to the host can be configured:</p>
       
   189      * <ul>
       
   190      *     <li>As read only.</li>
       
   191      *     <li>As write once.</li>
       
   192      *     <li>With a setter function, which can be used to manipulate
       
   193      *     values passed to Attribute's <a href="#method_set">set</a> method, before they are stored.</li>
       
   194      *     <li>With a getter function, which can be used to manipulate stored values,
       
   195      *     before they are returned by Attribute's <a href="#method_get">get</a> method.</li>
       
   196      *     <li>With a validator function, to validate values before they are stored.</li>
       
   197      * </ul>
       
   198      *
       
   199      * <p>See the <a href="#method_addAttr">addAttr</a> method, for the complete set of configuration
       
   200      * options available for attributes</p>.
       
   201      *
       
   202      * <p><strong>NOTE:</strong> Most implementations will be better off extending the <a href="Base.html">Base</a> class, 
       
   203      * instead of augmenting Attribute directly. Base augments Attribute and will handle the initial configuration 
       
   204      * of attributes for derived classes, accounting for values passed into the constructor.</p>
       
   205      *
       
   206      * @class Attribute
       
   207      * @uses EventTarget
       
   208      */
       
   209     function Attribute() {
       
   210 
       
   211         var host = this, // help compression
       
   212             attrs = this.constructor.ATTRS,
       
   213             Base = Y.Base;
       
   214 
       
   215         // Perf tweak - avoid creating event literals if not required.
       
   216         host._ATTR_E_FACADE = {};
       
   217 
       
   218         EventTarget.call(host, {emitFacade:true});
       
   219 
       
   220         // _conf maintained for backwards compat
       
   221         host._conf = host._state = new Y.State();
       
   222 
       
   223         host._stateProxy = host._stateProxy || null;
       
   224         host._requireAddAttr = host._requireAddAttr || false;
       
   225 
       
   226         // ATTRS support for Node, which is not Base based
       
   227         if ( attrs && !(Base && host instanceof Base)) {
       
   228             host.addAttrs(this._protectAttrs(attrs));
       
   229         }
       
   230     }
       
   231 
       
   232     /**
       
   233      * <p>The value to return from an attribute setter in order to prevent the set from going through.</p>
       
   234      *
       
   235      * <p>You can return this value from your setter if you wish to combine validator and setter 
       
   236      * functionality into a single setter function, which either returns the massaged value to be stored or 
       
   237      * Attribute.INVALID_VALUE to prevent invalid values from being stored.</p>
       
   238      *
       
   239      * @property Attribute.INVALID_VALUE
       
   240      * @type Object
       
   241      * @static
       
   242      * @final
       
   243      */
       
   244     Attribute.INVALID_VALUE = {};
       
   245     INVALID_VALUE = Attribute.INVALID_VALUE;
       
   246 
       
   247     /**
       
   248      * The list of properties which can be configured for 
       
   249      * each attribute (e.g. setter, getter, writeOnce etc.).
       
   250      *
       
   251      * This property is used internally as a whitelist for faster
       
   252      * Y.mix operations.
       
   253      *
       
   254      * @property Attribute._ATTR_CFG
       
   255      * @type Array
       
   256      * @static
       
   257      * @protected
       
   258      */
       
   259     Attribute._ATTR_CFG = [SETTER, GETTER, VALIDATOR, VALUE, VALUE_FN, WRITE_ONCE, READ_ONLY, LAZY_ADD, BROADCAST, BYPASS_PROXY];
       
   260 
       
   261     Attribute.prototype = {
       
   262         /**
       
   263          * <p>
       
   264          * Adds an attribute with the provided configuration to the host object.
       
   265          * </p>
       
   266          * <p>
       
   267          * The config argument object supports the following properties:
       
   268          * </p>
       
   269          * 
       
   270          * <dl>
       
   271          *    <dt>value &#60;Any&#62;</dt>
       
   272          *    <dd>The initial value to set on the attribute</dd>
       
   273          *
       
   274          *    <dt>valueFn &#60;Function&#62;</dt>
       
   275          *    <dd>A function, which will return the initial value to set on the attribute. This is useful
       
   276          *    for cases where the attribute configuration is defined statically, but needs to 
       
   277          *    reference the host instance ("this") to obtain an initial value.
       
   278          *    If defined, this precedence over the value property.</dd>
       
   279          *
       
   280          *    <dt>readOnly &#60;boolean&#62;</dt>
       
   281          *    <dd>Whether or not the attribute is read only. Attributes having readOnly set to true
       
   282          *        cannot be modified by invoking the set method.</dd>
       
   283          *
       
   284          *    <dt>writeOnce &#60;boolean&#62;</dt>
       
   285          *    <dd>Whether or not the attribute is "write once". Attributes having writeOnce set to true, 
       
   286          *        can only have their values set once, be it through the default configuration, 
       
   287          *        constructor configuration arguments, or by invoking set.</dd>
       
   288          *
       
   289          *    <dt>setter &#60;Function&#62;</dt>
       
   290          *    <dd>The setter function used to massage or normalize the value passed to the set method for the attribute. 
       
   291          *    The value returned by the setter will be the final stored value. Returning
       
   292          *    <a href="#property_Attribute.INVALID_VALUE">Attribute.INVALID_VALUE</a>, from the setter will prevent
       
   293          *    the value from being stored.</dd>
       
   294          *
       
   295          *    <dt>getter &#60;Function&#62;</dt>
       
   296          *    <dd>The getter function used to massage or normalize the value returned by the get method for the attribute.
       
   297          *    The value returned by the getter function is the value which will be returned to the user when they 
       
   298          *    invoke get.</dd>
       
   299          *
       
   300          *    <dt>validator &#60;Function&#62;</dt>
       
   301          *    <dd>The validator function invoked prior to setting the stored value. Returning
       
   302          *    false from the validator function will prevent the value from being stored.</dd>
       
   303          *    
       
   304          *    <dt>broadcast &#60;int&#62;</dt>
       
   305          *    <dd>If and how attribute change events for this attribute should be broadcast. See CustomEvent's <a href="CustomEvent.html#property_broadcast">broadcast</a> property for 
       
   306          *    valid values. By default attribute change events are not broadcast.</dd>
       
   307          *
       
   308          *    <dt>lazyAdd &#60;boolean&#62;</dt>
       
   309          *    <dd>Whether or not to delay initialization of the attribute until the first call to get/set it. 
       
   310          *    This flag can be used to over-ride lazy initialization on a per attribute basis, when adding multiple attributes through 
       
   311          *    the <a href="#method_addAttrs">addAttrs</a> method.</dd>
       
   312          *
       
   313          * </dl>
       
   314          *
       
   315          * <p>The setter, getter and validator are invoked with the value and name passed in as the first and second arguments, and with
       
   316          * the context ("this") set to the host object.</p>
       
   317          *
       
   318          * <p>Configuration properties outside of the list mentioned above are considered private properties used internally by attribute, and are not intended for public use.</p>
       
   319          * 
       
   320          * @method addAttr
       
   321          *
       
   322          * @param {String} name The name of the attribute.
       
   323          * @param {Object} config An object with attribute configuration property/value pairs, specifying the configuration for the attribute.
       
   324          *
       
   325          * <p>
       
   326          * <strong>NOTE:</strong> The configuration object is modified when adding an attribute, so if you need 
       
   327          * to protect the original values, you will need to merge the object.
       
   328          * </p>
       
   329          *
       
   330          * @param {boolean} lazy (optional) Whether or not to add this attribute lazily (on the first call to get/set). 
       
   331          *
       
   332          * @return {Object} A reference to the host object.
       
   333          *
       
   334          * @chainable
       
   335          */
       
   336         addAttr: function(name, config, lazy) {
       
   337 
       
   338 
       
   339             var host = this, // help compression
       
   340                 state = host._state,
       
   341                 value,
       
   342                 hasValue;
       
   343 
       
   344             lazy = (LAZY_ADD in config) ? config[LAZY_ADD] : lazy;
       
   345 
       
   346             if (lazy && !host.attrAdded(name)) {
       
   347                 state.add(name, LAZY, config || {});
       
   348                 state.add(name, ADDED, true);
       
   349             } else {
       
   350 
       
   351 
       
   352                 if (!host.attrAdded(name) || state.get(name, IS_LAZY_ADD)) {
       
   353 
       
   354                     config = config || {};
       
   355 
       
   356                     hasValue = (VALUE in config);
       
   357 
       
   358 
       
   359                     if(hasValue) {
       
   360                         // We'll go through set, don't want to set value in _state directly
       
   361                         value = config.value;
       
   362                         delete config.value;
       
   363                     }
       
   364 
       
   365                     config.added = true;
       
   366                     config.initializing = true;
       
   367 
       
   368                     state.addAll(name, config);
       
   369 
       
   370                     if (hasValue) {
       
   371                         // Go through set, so that raw values get normalized/validated
       
   372                         host.set(name, value);
       
   373                     }
       
   374 
       
   375                     state.remove(name, INITIALIZING);
       
   376                 }
       
   377             }
       
   378 
       
   379             return host;
       
   380         },
       
   381 
       
   382         /**
       
   383          * Checks if the given attribute has been added to the host
       
   384          *
       
   385          * @method attrAdded
       
   386          * @param {String} name The name of the attribute to check.
       
   387          * @return {boolean} true if an attribute with the given name has been added, false if it hasn't. This method will return true for lazily added attributes.
       
   388          */
       
   389         attrAdded: function(name) {
       
   390             return !!this._state.get(name, ADDED);
       
   391         },
       
   392 
       
   393         /**
       
   394          * Updates the configuration of an attribute which has already been added.
       
   395          * <p>
       
   396          * The properties which can be modified through this interface are limited
       
   397          * to the following subset of attributes, which can be safely modified
       
   398          * after a value has already been set on the attribute: readOnly, writeOnce, 
       
   399          * broadcast and getter.
       
   400          * </p>
       
   401          * @method modifyAttr
       
   402          * @param {String} name The name of the attribute whose configuration is to be updated.
       
   403          * @param {Object} config An object with configuration property/value pairs, specifying the configuration properties to modify.
       
   404          */
       
   405         modifyAttr: function(name, config) {
       
   406             var host = this, // help compression
       
   407                 prop, state;
       
   408 
       
   409             if (host.attrAdded(name)) {
       
   410 
       
   411                 if (host._isLazyAttr(name)) {
       
   412                     host._addLazyAttr(name);
       
   413                 }
       
   414 
       
   415                 state = host._state;
       
   416                 for (prop in config) {
       
   417                     if (MODIFIABLE[prop] && config.hasOwnProperty(prop)) {
       
   418                         state.add(name, prop, config[prop]);
       
   419 
       
   420                         // If we reconfigured broadcast, need to republish
       
   421                         if (prop === BROADCAST) {
       
   422                             state.remove(name, PUBLISHED);
       
   423                         }
       
   424                     }
       
   425                 }
       
   426             }
       
   427 
       
   428         },
       
   429 
       
   430         /**
       
   431          * Removes an attribute from the host object
       
   432          *
       
   433          * @method removeAttr
       
   434          * @param {String} name The name of the attribute to be removed.
       
   435          */
       
   436         removeAttr: function(name) {
       
   437             this._state.removeAll(name);
       
   438         },
       
   439 
       
   440         /**
       
   441          * Returns the current value of the attribute. If the attribute
       
   442          * has been configured with a 'getter' function, this method will delegate
       
   443          * to the 'getter' to obtain the value of the attribute.
       
   444          *
       
   445          * @method get
       
   446          *
       
   447          * @param {String} name The name of the attribute. If the value of the attribute is an Object, 
       
   448          * dot notation can be used to obtain the value of a property of the object (e.g. <code>get("x.y.z")</code>)
       
   449          *
       
   450          * @return {Any} The value of the attribute
       
   451          */
       
   452         get : function(name) {
       
   453             return this._getAttr(name);
       
   454         },
       
   455 
       
   456         /**
       
   457          * Checks whether or not the attribute is one which has been
       
   458          * added lazily and still requires initialization.
       
   459          *
       
   460          * @method _isLazyAttr
       
   461          * @private
       
   462          * @param {String} name The name of the attribute
       
   463          * @return {boolean} true if it's a lazily added attribute, false otherwise.
       
   464          */
       
   465         _isLazyAttr: function(name) {
       
   466             return this._state.get(name, LAZY);
       
   467         },
       
   468 
       
   469         /**
       
   470          * Finishes initializing an attribute which has been lazily added.
       
   471          *
       
   472          * @method _addLazyAttr
       
   473          * @private
       
   474          * @param {Object} name The name of the attribute
       
   475          */
       
   476         _addLazyAttr: function(name) {
       
   477             var state = this._state,
       
   478                 lazyCfg = state.get(name, LAZY);
       
   479 
       
   480             state.add(name, IS_LAZY_ADD, true);
       
   481             state.remove(name, LAZY);
       
   482             this.addAttr(name, lazyCfg);
       
   483         },
       
   484 
       
   485         /**
       
   486          * Sets the value of an attribute.
       
   487          *
       
   488          * @method set
       
   489          * @chainable
       
   490          *
       
   491          * @param {String} name The name of the attribute. If the 
       
   492          * current value of the attribute is an Object, dot notation can be used
       
   493          * to set the value of a property within the object (e.g. <code>set("x.y.z", 5)</code>).
       
   494          *
       
   495          * @param {Any} value The value to set the attribute to.
       
   496          *
       
   497          * @param {Object} opts (Optional) Optional event data to be mixed into
       
   498          * the event facade passed to subscribers of the attribute's change event. This 
       
   499          * can be used as a flexible way to identify the source of a call to set, allowing 
       
   500          * the developer to distinguish between set called internally by the host, vs. 
       
   501          * set called externally by the application developer.
       
   502          *
       
   503          * @return {Object} A reference to the host object.
       
   504          */
       
   505         set : function(name, val, opts) {
       
   506             return this._setAttr(name, val, opts);
       
   507         },
       
   508 
       
   509         /**
       
   510          * Resets the attribute (or all attributes) to its initial value, as long as
       
   511          * the attribute is not readOnly, or writeOnce.
       
   512          *
       
   513          * @method reset
       
   514          * @param {String} name Optional. The name of the attribute to reset.  If omitted, all attributes are reset.
       
   515          * @return {Object} A reference to the host object.
       
   516          * @chainable
       
   517          */
       
   518         reset : function(name) {
       
   519             var host = this,  // help compression
       
   520                 added;
       
   521 
       
   522             if (name) {
       
   523                 if (host._isLazyAttr(name)) {
       
   524                     host._addLazyAttr(name);
       
   525                 }
       
   526                 host.set(name, host._state.get(name, INIT_VALUE));
       
   527             } else {
       
   528                 added = host._state.data.added;
       
   529                 Y.each(added, function(v, n) {
       
   530                     host.reset(n);
       
   531                 }, host);
       
   532             }
       
   533             return host;
       
   534         },
       
   535 
       
   536         /**
       
   537          * Allows setting of readOnly/writeOnce attributes. See <a href="#method_set">set</a> for argument details.
       
   538          *
       
   539          * @method _set
       
   540          * @protected
       
   541          * @chainable
       
   542          * 
       
   543          * @param {String} name The name of the attribute.
       
   544          * @param {Any} val The value to set the attribute to.
       
   545          * @param {Object} opts (Optional) Optional event data to be mixed into
       
   546          * the event facade passed to subscribers of the attribute's change event.
       
   547          * @return {Object} A reference to the host object.
       
   548          */
       
   549         _set : function(name, val, opts) {
       
   550             return this._setAttr(name, val, opts, true);
       
   551         },
       
   552 
       
   553         /**
       
   554          * Provides the common implementation for the public get method,
       
   555          * allowing Attribute hosts to over-ride either method.
       
   556          *
       
   557          * See <a href="#method_get">get</a> for argument details.
       
   558          *
       
   559          * @method _getAttr
       
   560          * @protected
       
   561          * @chainable
       
   562          *
       
   563          * @param {String} name The name of the attribute.
       
   564          * @return {Any} The value of the attribute.
       
   565          */
       
   566         _getAttr : function(name) {
       
   567             var host = this, // help compression
       
   568                 fullName = name,
       
   569                 state = host._state,
       
   570                 path,
       
   571                 getter,
       
   572                 val,
       
   573                 cfg;
       
   574 
       
   575             if (name.indexOf(DOT) !== -1) {
       
   576                 path = name.split(DOT);
       
   577                 name = path.shift();
       
   578             }
       
   579 
       
   580             // On Demand - Should be rare - handles out of order valueFn references
       
   581             if (host._tCfgs && host._tCfgs[name]) {
       
   582                 cfg = {};
       
   583                 cfg[name] = host._tCfgs[name];
       
   584                 delete host._tCfgs[name];
       
   585                 host._addAttrs(cfg, host._tVals);
       
   586             }
       
   587 
       
   588             // Lazy Init
       
   589             if (host._isLazyAttr(name)) {
       
   590                 host._addLazyAttr(name);
       
   591             }
       
   592 
       
   593             val = host._getStateVal(name);
       
   594             getter = state.get(name, GETTER);
       
   595 
       
   596             val = (getter) ? getter.call(host, val, fullName) : val;
       
   597             val = (path) ? O.getValue(val, path) : val;
       
   598 
       
   599             return val;
       
   600         },
       
   601 
       
   602         /**
       
   603          * Provides the common implementation for the public set and protected _set methods.
       
   604          *
       
   605          * See <a href="#method_set">set</a> for argument details.
       
   606          *
       
   607          * @method _setAttr
       
   608          * @protected
       
   609          * @chainable
       
   610          *
       
   611          * @param {String} name The name of the attribute.
       
   612          * @param {Any} value The value to set the attribute to.
       
   613          * @param {Object} opts (Optional) Optional event data to be mixed into
       
   614          * the event facade passed to subscribers of the attribute's change event.
       
   615          * @param {boolean} force If true, allows the caller to set values for 
       
   616          * readOnly or writeOnce attributes which have already been set.
       
   617          *
       
   618          * @return {Object} A reference to the host object.
       
   619          */
       
   620         _setAttr : function(name, val, opts, force) {
       
   621             var allowSet = true,
       
   622                 state = this._state,
       
   623                 stateProxy = this._stateProxy,
       
   624                 data = state.data,
       
   625                 initialSet,
       
   626                 strPath,
       
   627                 path,
       
   628                 currVal;
       
   629 
       
   630             if (name.indexOf(DOT) !== -1) {
       
   631                 strPath = name;
       
   632                 path = name.split(DOT);
       
   633                 name = path.shift();
       
   634             }
       
   635 
       
   636             if (this._isLazyAttr(name)) {
       
   637                 this._addLazyAttr(name);
       
   638             }
       
   639 
       
   640             initialSet = (!data.value || !(name in data.value));
       
   641 
       
   642             if (stateProxy && name in stateProxy && !this._state.get(name, BYPASS_PROXY)) {
       
   643                 // TODO: Value is always set for proxy. Can we do any better? Maybe take a snapshot as the initial value for the first call to set? 
       
   644                 initialSet = false;
       
   645             }
       
   646 
       
   647             if (this._requireAddAttr && !this.attrAdded(name)) {
       
   648             } else {
       
   649 
       
   650                 if (!initialSet && !force) {
       
   651 
       
   652                     if (state.get(name, WRITE_ONCE)) {
       
   653                         allowSet = false;
       
   654                     }
       
   655 
       
   656                     if (state.get(name, READ_ONLY)) {
       
   657                         allowSet = false;
       
   658                     }
       
   659                 }
       
   660 
       
   661                 if (allowSet) {
       
   662                     // Don't need currVal if initialSet (might fail in custom getter if it always expects a non-undefined/non-null value)
       
   663                     if (!initialSet) {
       
   664                         currVal =  this.get(name);
       
   665                     }
       
   666 
       
   667                     if (path) {
       
   668                        val = O.setValue(Y.clone(currVal), path, val);
       
   669 
       
   670                        if (val === undefined) {
       
   671                            allowSet = false;
       
   672                        }
       
   673                     }
       
   674 
       
   675                     if (allowSet) {
       
   676                         if (state.get(name, INITIALIZING)) {
       
   677                             this._setAttrVal(name, strPath, currVal, val);
       
   678                         } else {
       
   679                             this._fireAttrChange(name, strPath, currVal, val, opts);
       
   680                         }
       
   681                     }
       
   682                 }
       
   683             }
       
   684 
       
   685             return this;
       
   686         },
       
   687 
       
   688         /**
       
   689          * Utility method to help setup the event payload and fire the attribute change event.
       
   690          * 
       
   691          * @method _fireAttrChange
       
   692          * @private
       
   693          * @param {String} attrName The name of the attribute
       
   694          * @param {String} subAttrName The full path of the property being changed, 
       
   695          * if this is a sub-attribute value being change. Otherwise null.
       
   696          * @param {Any} currVal The current value of the attribute
       
   697          * @param {Any} newVal The new value of the attribute
       
   698          * @param {Object} opts Any additional event data to mix into the attribute change event's event facade.
       
   699          */
       
   700         _fireAttrChange : function(attrName, subAttrName, currVal, newVal, opts) {
       
   701             var host = this,
       
   702                 eventName = attrName + CHANGE,
       
   703                 state = host._state,
       
   704                 facade;
       
   705 
       
   706             if (!state.get(attrName, PUBLISHED)) {
       
   707                 host.publish(eventName, {
       
   708                     queuable:false, 
       
   709                     defaultFn:host._defAttrChangeFn, 
       
   710                     silent:true,
       
   711                     broadcast : state.get(attrName, BROADCAST)
       
   712                 });
       
   713                 state.add(attrName, PUBLISHED, true);
       
   714             }
       
   715 
       
   716             facade = (opts) ? Y.merge(opts) : host._ATTR_E_FACADE;
       
   717 
       
   718             facade.type = eventName;
       
   719             facade.attrName = attrName;
       
   720             facade.subAttrName = subAttrName;
       
   721             facade.prevVal = currVal;
       
   722             facade.newVal = newVal;
       
   723 
       
   724             host.fire(facade);
       
   725         },
       
   726 
       
   727         /**
       
   728          * Default function for attribute change events.
       
   729          *
       
   730          * @private
       
   731          * @method _defAttrChangeFn
       
   732          * @param {EventFacade} e The event object for attribute change events.
       
   733          */
       
   734         _defAttrChangeFn : function(e) {
       
   735             if (!this._setAttrVal(e.attrName, e.subAttrName, e.prevVal, e.newVal)) {
       
   736                 // Prevent "after" listeners from being invoked since nothing changed.
       
   737                 e.stopImmediatePropagation();
       
   738             } else {
       
   739                 e.newVal = this._getStateVal(e.attrName);
       
   740             }
       
   741         },
       
   742 
       
   743         /**
       
   744          * Gets the stored value for the attribute, from either the 
       
   745          * internal state object, or the state proxy if it exits
       
   746          * 
       
   747          * @method _getStateVal
       
   748          * @private
       
   749          * @param {String} name The name of the attribute
       
   750          * @return {Any} The stored value of the attribute
       
   751          */
       
   752         _getStateVal : function(name) {
       
   753             var stateProxy = this._stateProxy;
       
   754             return stateProxy && (name in stateProxy) && !this._state.get(name, BYPASS_PROXY) ? stateProxy[name] : this._state.get(name, VALUE);
       
   755         },
       
   756 
       
   757         /**
       
   758          * Sets the stored value for the attribute, in either the 
       
   759          * internal state object, or the state proxy if it exits
       
   760          *
       
   761          * @method _setStateVal
       
   762          * @private
       
   763          * @param {String} name The name of the attribute
       
   764          * @param {Any} value The value of the attribute
       
   765          */
       
   766         _setStateVal : function(name, value) {
       
   767             var stateProxy = this._stateProxy;
       
   768             if (stateProxy && (name in stateProxy) && !this._state.get(name, BYPASS_PROXY)) {
       
   769                 stateProxy[name] = value;
       
   770             } else {
       
   771                 this._state.add(name, VALUE, value);
       
   772             }
       
   773         },
       
   774 
       
   775         /**
       
   776          * Updates the stored value of the attribute in the privately held State object,
       
   777          * if validation and setter passes.
       
   778          *
       
   779          * @method _setAttrVal
       
   780          * @private
       
   781          * @param {String} attrName The attribute name.
       
   782          * @param {String} subAttrName The sub-attribute name, if setting a sub-attribute property ("x.y.z").
       
   783          * @param {Any} prevVal The currently stored value of the attribute.
       
   784          * @param {Any} newVal The value which is going to be stored.
       
   785          * 
       
   786          * @return {booolean} true if the new attribute value was stored, false if not.
       
   787          */
       
   788         _setAttrVal : function(attrName, subAttrName, prevVal, newVal) {
       
   789 
       
   790             var host = this,
       
   791                 allowSet = true,
       
   792                 state = host._state,
       
   793 
       
   794                 validator = state.get(attrName, VALIDATOR),
       
   795                 setter = state.get(attrName, SETTER),
       
   796                 initializing = state.get(attrName, INITIALIZING),
       
   797                 prevValRaw = this._getStateVal(attrName),
       
   798 
       
   799                 name = subAttrName || attrName,
       
   800                 retVal,
       
   801                 valid;
       
   802 
       
   803             if (validator) {
       
   804                 valid = validator.call(host, newVal, name);
       
   805 
       
   806                 if (!valid && initializing) {
       
   807                     newVal = state.get(attrName, DEF_VALUE);
       
   808                     valid = true; // Assume it's valid, for perf.
       
   809                 }
       
   810             }
       
   811 
       
   812             if (!validator || valid) {
       
   813                 if (setter) {
       
   814                     retVal = setter.call(host, newVal, name);
       
   815 
       
   816                     if (retVal === INVALID_VALUE) {
       
   817                         allowSet = false;
       
   818                     } else if (retVal !== undefined){
       
   819                         newVal = retVal;
       
   820                     }
       
   821                 }
       
   822 
       
   823                 if (allowSet) {
       
   824                     if(!subAttrName && (newVal === prevValRaw) && !Lang.isObject(newVal)) {
       
   825                         allowSet = false;
       
   826                     } else {
       
   827                         // Store value
       
   828                         if (state.get(attrName, INIT_VALUE) === undefined) {
       
   829                             state.add(attrName, INIT_VALUE, newVal);
       
   830                         }
       
   831                         host._setStateVal(attrName, newVal);
       
   832                     }
       
   833                 }
       
   834 
       
   835             } else {
       
   836                 allowSet = false;
       
   837             }
       
   838 
       
   839             return allowSet;
       
   840         },
       
   841 
       
   842         /**
       
   843          * Sets multiple attribute values.
       
   844          *
       
   845          * @method setAttrs
       
   846          * @param {Object} attrs  An object with attributes name/value pairs.
       
   847          * @return {Object} A reference to the host object.
       
   848          * @chainable
       
   849          */
       
   850         setAttrs : function(attrs, opts) {
       
   851             return this._setAttrs(attrs, opts);
       
   852         },
       
   853 
       
   854         /**
       
   855          * Implementation behind the public setAttrs method, to set multiple attribute values.
       
   856          *
       
   857          * @method _setAttrs
       
   858          * @protected
       
   859          * @param {Object} attrs  An object with attributes name/value pairs.
       
   860          * @return {Object} A reference to the host object.
       
   861          * @chainable
       
   862          */
       
   863         _setAttrs : function(attrs, opts) {
       
   864             for (var attr in attrs) {
       
   865                 if ( attrs.hasOwnProperty(attr) ) {
       
   866                     this.set(attr, attrs[attr]);
       
   867                 }
       
   868             }
       
   869             return this;
       
   870         },
       
   871 
       
   872         /**
       
   873          * Gets multiple attribute values.
       
   874          *
       
   875          * @method getAttrs
       
   876          * @param {Array | boolean} attrs Optional. An array of attribute names. If omitted, all attribute values are
       
   877          * returned. If set to true, all attributes modified from their initial values are returned.
       
   878          * @return {Object} An object with attribute name/value pairs.
       
   879          */
       
   880         getAttrs : function(attrs) {
       
   881             return this._getAttrs(attrs);
       
   882         },
       
   883 
       
   884         /**
       
   885          * Implementation behind the public getAttrs method, to get multiple attribute values.
       
   886          *
       
   887          * @method _getAttrs
       
   888          * @protected
       
   889          * @param {Array | boolean} attrs Optional. An array of attribute names. If omitted, all attribute values are
       
   890          * returned. If set to true, all attributes modified from their initial values are returned.
       
   891          * @return {Object} An object with attribute name/value pairs.
       
   892          */
       
   893         _getAttrs : function(attrs) {
       
   894             var host = this,
       
   895                 o = {}, 
       
   896                 i, l, attr, val,
       
   897                 modifiedOnly = (attrs === true);
       
   898 
       
   899             attrs = (attrs && !modifiedOnly) ? attrs : O.keys(host._state.data.added);
       
   900 
       
   901             for (i = 0, l = attrs.length; i < l; i++) {
       
   902                 // Go through get, to honor cloning/normalization
       
   903                 attr = attrs[i];
       
   904                 val = host.get(attr);
       
   905 
       
   906                 if (!modifiedOnly || host._getStateVal(attr) != host._state.get(attr, INIT_VALUE)) {
       
   907                     o[attr] = host.get(attr); 
       
   908                 }
       
   909             }
       
   910 
       
   911             return o;
       
   912         },
       
   913 
       
   914         /**
       
   915          * Configures a group of attributes, and sets initial values.
       
   916          *
       
   917          * <p>
       
   918          * <strong>NOTE:</strong> This method does not isolate the configuration object by merging/cloning. 
       
   919          * The caller is responsible for merging/cloning the configuration object if required.
       
   920          * </p>
       
   921          *
       
   922          * @method addAttrs
       
   923          * @chainable
       
   924          *
       
   925          * @param {Object} cfgs An object with attribute name/configuration pairs.
       
   926          * @param {Object} values An object with attribute name/value pairs, defining the initial values to apply.
       
   927          * Values defined in the cfgs argument will be over-written by values in this argument unless defined as read only.
       
   928          * @param {boolean} lazy Whether or not to delay the intialization of these attributes until the first call to get/set.
       
   929          * Individual attributes can over-ride this behavior by defining a lazyAdd configuration property in their configuration.
       
   930          * See <a href="#method_addAttr">addAttr</a>.
       
   931          * 
       
   932          * @return {Object} A reference to the host object.
       
   933          */
       
   934         addAttrs : function(cfgs, values, lazy) {
       
   935             var host = this; // help compression
       
   936             if (cfgs) {
       
   937                 host._tCfgs = cfgs;
       
   938                 host._tVals = host._normAttrVals(values);
       
   939                 host._addAttrs(cfgs, host._tVals, lazy);
       
   940                 host._tCfgs = host._tVals = null;
       
   941             }
       
   942 
       
   943             return host;
       
   944         },
       
   945 
       
   946         /**
       
   947          * Implementation behind the public addAttrs method. 
       
   948          * 
       
   949          * This method is invoked directly by get if it encounters a scenario 
       
   950          * in which an attribute's valueFn attempts to obtain the 
       
   951          * value an attribute in the same group of attributes, which has not yet 
       
   952          * been added (on demand initialization).
       
   953          *
       
   954          * @method _addAttrs
       
   955          * @private
       
   956          * @param {Object} cfgs An object with attribute name/configuration pairs.
       
   957          * @param {Object} values An object with attribute name/value pairs, defining the initial values to apply.
       
   958          * Values defined in the cfgs argument will be over-written by values in this argument unless defined as read only.
       
   959          * @param {boolean} lazy Whether or not to delay the intialization of these attributes until the first call to get/set.
       
   960          * Individual attributes can over-ride this behavior by defining a lazyAdd configuration property in their configuration.
       
   961          * See <a href="#method_addAttr">addAttr</a>.
       
   962          */
       
   963         _addAttrs : function(cfgs, values, lazy) {
       
   964             var host = this, // help compression
       
   965                 attr,
       
   966                 attrCfg,
       
   967                 value;
       
   968 
       
   969             for (attr in cfgs) {
       
   970                 if (cfgs.hasOwnProperty(attr)) {
       
   971 
       
   972                     // Not Merging. Caller is responsible for isolating configs
       
   973                     attrCfg = cfgs[attr];
       
   974                     attrCfg.defaultValue = attrCfg.value;
       
   975 
       
   976                     // Handle simple, complex and user values, accounting for read-only
       
   977                     value = host._getAttrInitVal(attr, attrCfg, host._tVals);
       
   978 
       
   979                     if (value !== undefined) {
       
   980                         attrCfg.value = value;
       
   981                     }
       
   982 
       
   983                     if (host._tCfgs[attr]) {
       
   984                         delete host._tCfgs[attr];
       
   985                     }
       
   986 
       
   987                     host.addAttr(attr, attrCfg, lazy);
       
   988                 }
       
   989             }
       
   990         },
       
   991 
       
   992         /**
       
   993          * Utility method to protect an attribute configuration
       
   994          * hash, by merging the entire object and the individual 
       
   995          * attr config objects. 
       
   996          *
       
   997          * @method _protectAttrs
       
   998          * @protected
       
   999          * @param {Object} attrs A hash of attribute to configuration object pairs.
       
  1000          * @return {Object} A protected version of the attrs argument.
       
  1001          */
       
  1002         _protectAttrs : function(attrs) {
       
  1003             if (attrs) {
       
  1004                 attrs = Y.merge(attrs);
       
  1005                 for (var attr in attrs) {
       
  1006                     if (attrs.hasOwnProperty(attr)) {
       
  1007                         attrs[attr] = Y.merge(attrs[attr]);
       
  1008                     }
       
  1009                 }
       
  1010             }
       
  1011             return attrs;
       
  1012         },
       
  1013 
       
  1014         /**
       
  1015          * Utility method to normalize attribute values. The base implementation 
       
  1016          * simply merges the hash to protect the original.
       
  1017          *
       
  1018          * @method _normAttrVals
       
  1019          * @param {Object} valueHash An object with attribute name/value pairs
       
  1020          *
       
  1021          * @return {Object}
       
  1022          *
       
  1023          * @private
       
  1024          */
       
  1025         _normAttrVals : function(valueHash) {
       
  1026             return (valueHash) ? Y.merge(valueHash) : null;
       
  1027         },
       
  1028 
       
  1029         /**
       
  1030          * Returns the initial value of the given attribute from
       
  1031          * either the default configuration provided, or the 
       
  1032          * over-ridden value if it exists in the set of initValues 
       
  1033          * provided and the attribute is not read-only.
       
  1034          *
       
  1035          * @param {String} attr The name of the attribute
       
  1036          * @param {Object} cfg The attribute configuration object
       
  1037          * @param {Object} initValues The object with simple and complex attribute name/value pairs returned from _normAttrVals
       
  1038          *
       
  1039          * @return {Any} The initial value of the attribute.
       
  1040          *
       
  1041          * @method _getAttrInitVal
       
  1042          * @private
       
  1043          */
       
  1044         _getAttrInitVal : function(attr, cfg, initValues) {
       
  1045 
       
  1046             // init value is provided by the user if it exists, else, provided by the config
       
  1047             var val = (!cfg[READ_ONLY] && initValues && initValues.hasOwnProperty(attr)) ?
       
  1048                             val = initValues[attr] :
       
  1049                             (cfg[VALUE_FN]) ?
       
  1050                                 cfg[VALUE_FN].call(this) : 
       
  1051                                 cfg[VALUE];
       
  1052 
       
  1053 
       
  1054             return val;
       
  1055         }
       
  1056     };
       
  1057 
       
  1058     // Basic prototype augment - no lazy constructor invocation.
       
  1059     Y.mix(Attribute, EventTarget, false, null, 1);
       
  1060 
       
  1061     Y.Attribute = Attribute;
       
  1062 
       
  1063 
       
  1064 }, '3.0.0' ,{requires:['event-custom']});
       
  1065 YUI.add('attribute-complex', function(Y) {
       
  1066 
       
  1067     /**
       
  1068      * Adds support for attribute providers to handle complex attributes in the constructor
       
  1069      *
       
  1070      * @module attribute
       
  1071      * @submodule attribute-complex
       
  1072      * @for Attribute
       
  1073      */
       
  1074 
       
  1075     var O = Y.Object,
       
  1076         DOT = ".";
       
  1077 
       
  1078     Y.Attribute.Complex = function() {};
       
  1079     Y.Attribute.Complex.prototype = {
       
  1080 
       
  1081         /**
       
  1082          * Utility method to split out simple attribute name/value pairs ("x") 
       
  1083          * from complex attribute name/value pairs ("x.y.z"), so that complex
       
  1084          * attributes can be keyed by the top level attribute name.
       
  1085          *
       
  1086          * @method _normAttrVals
       
  1087          * @param {Object} valueHash An object with attribute name/value pairs
       
  1088          *
       
  1089          * @return {Object} An object literal with 2 properties - "simple" and "complex",
       
  1090          * containing simple and complex attribute values respectively keyed 
       
  1091          * by the top level attribute name, or null, if valueHash is falsey.
       
  1092          *
       
  1093          * @private
       
  1094          */
       
  1095         _normAttrVals : function(valueHash) {
       
  1096             var vals = {},
       
  1097                 subvals = {},
       
  1098                 path,
       
  1099                 attr,
       
  1100                 v, k;
       
  1101 
       
  1102             if (valueHash) {
       
  1103                 for (k in valueHash) {
       
  1104                     if (valueHash.hasOwnProperty(k)) {
       
  1105                         if (k.indexOf(DOT) !== -1) {
       
  1106                             path = k.split(DOT);
       
  1107                             attr = path.shift();
       
  1108                             v = subvals[attr] = subvals[attr] || [];
       
  1109                             v[v.length] = {
       
  1110                                 path : path, 
       
  1111                                 value: valueHash[k]
       
  1112                             };
       
  1113                         } else {
       
  1114                             vals[k] = valueHash[k];
       
  1115                         }
       
  1116                     }
       
  1117                 }
       
  1118                 return { simple:vals, complex:subvals };
       
  1119             } else {
       
  1120                 return null;
       
  1121             }
       
  1122         },
       
  1123 
       
  1124         /**
       
  1125          * Returns the initial value of the given attribute from
       
  1126          * either the default configuration provided, or the 
       
  1127          * over-ridden value if it exists in the set of initValues 
       
  1128          * provided and the attribute is not read-only.
       
  1129          *
       
  1130          * @param {String} attr The name of the attribute
       
  1131          * @param {Object} cfg The attribute configuration object
       
  1132          * @param {Object} initValues The object with simple and complex attribute name/value pairs returned from _normAttrVals
       
  1133          *
       
  1134          * @return {Any} The initial value of the attribute.
       
  1135          *
       
  1136          * @method _getAttrInitVal
       
  1137          * @private
       
  1138          */
       
  1139         _getAttrInitVal : function(attr, cfg, initValues) {
       
  1140 
       
  1141             var val = (cfg.valueFn) ? cfg.valueFn.call(this) : cfg.value,
       
  1142                 simple,
       
  1143                 complex,
       
  1144                 i,
       
  1145                 l,
       
  1146                 path,
       
  1147                 subval,
       
  1148                 subvals;
       
  1149 
       
  1150             if (!cfg.readOnly && initValues) {
       
  1151 
       
  1152                 // Simple Attributes
       
  1153                 simple = initValues.simple;
       
  1154                 if (simple && simple.hasOwnProperty(attr)) {
       
  1155                     val = simple[attr];
       
  1156                 }
       
  1157 
       
  1158                 // Complex Attributes (complex values applied, after simple, incase both are set)
       
  1159                 complex = initValues.complex;
       
  1160                 if (complex && complex.hasOwnProperty(attr)) {
       
  1161                     subvals = complex[attr];
       
  1162                     for (i = 0, l = subvals.length; i < l; ++i) {
       
  1163                         path = subvals[i].path;
       
  1164                         subval = subvals[i].value;
       
  1165                         O.setValue(val, path, subval);
       
  1166                     }
       
  1167                 }
       
  1168             }
       
  1169 
       
  1170             return val;
       
  1171         }
       
  1172     };
       
  1173 
       
  1174     Y.mix(Y.Attribute, Y.Attribute.Complex, true, null, 1);
       
  1175 
       
  1176 
       
  1177 }, '3.0.0' ,{requires:['attribute-base']});
       
  1178 
       
  1179 
       
  1180 YUI.add('attribute', function(Y){}, '3.0.0' ,{use:['attribute-base', 'attribute-complex']});
       
  1181