src/cm/media/js/lib/yui/yui3.0.0/build/attribute/attribute-debug.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         Y.log('Attribute constructor called', 'info', 'attribute');
       
   211 
       
   212         var host = this, // help compression
       
   213             attrs = this.constructor.ATTRS,
       
   214             Base = Y.Base;
       
   215 
       
   216         // Perf tweak - avoid creating event literals if not required.
       
   217         host._ATTR_E_FACADE = {};
       
   218 
       
   219         EventTarget.call(host, {emitFacade:true});
       
   220 
       
   221         // _conf maintained for backwards compat
       
   222         host._conf = host._state = new Y.State();
       
   223 
       
   224         host._stateProxy = host._stateProxy || null;
       
   225         host._requireAddAttr = host._requireAddAttr || false;
       
   226 
       
   227         // ATTRS support for Node, which is not Base based
       
   228         if ( attrs && !(Base && host instanceof Base)) {
       
   229             host.addAttrs(this._protectAttrs(attrs));
       
   230         }
       
   231     }
       
   232 
       
   233     /**
       
   234      * <p>The value to return from an attribute setter in order to prevent the set from going through.</p>
       
   235      *
       
   236      * <p>You can return this value from your setter if you wish to combine validator and setter 
       
   237      * functionality into a single setter function, which either returns the massaged value to be stored or 
       
   238      * Attribute.INVALID_VALUE to prevent invalid values from being stored.</p>
       
   239      *
       
   240      * @property Attribute.INVALID_VALUE
       
   241      * @type Object
       
   242      * @static
       
   243      * @final
       
   244      */
       
   245     Attribute.INVALID_VALUE = {};
       
   246     INVALID_VALUE = Attribute.INVALID_VALUE;
       
   247 
       
   248     /**
       
   249      * The list of properties which can be configured for 
       
   250      * each attribute (e.g. setter, getter, writeOnce etc.).
       
   251      *
       
   252      * This property is used internally as a whitelist for faster
       
   253      * Y.mix operations.
       
   254      *
       
   255      * @property Attribute._ATTR_CFG
       
   256      * @type Array
       
   257      * @static
       
   258      * @protected
       
   259      */
       
   260     Attribute._ATTR_CFG = [SETTER, GETTER, VALIDATOR, VALUE, VALUE_FN, WRITE_ONCE, READ_ONLY, LAZY_ADD, BROADCAST, BYPASS_PROXY];
       
   261 
       
   262     Attribute.prototype = {
       
   263         /**
       
   264          * <p>
       
   265          * Adds an attribute with the provided configuration to the host object.
       
   266          * </p>
       
   267          * <p>
       
   268          * The config argument object supports the following properties:
       
   269          * </p>
       
   270          * 
       
   271          * <dl>
       
   272          *    <dt>value &#60;Any&#62;</dt>
       
   273          *    <dd>The initial value to set on the attribute</dd>
       
   274          *
       
   275          *    <dt>valueFn &#60;Function&#62;</dt>
       
   276          *    <dd>A function, which will return the initial value to set on the attribute. This is useful
       
   277          *    for cases where the attribute configuration is defined statically, but needs to 
       
   278          *    reference the host instance ("this") to obtain an initial value.
       
   279          *    If defined, this precedence over the value property.</dd>
       
   280          *
       
   281          *    <dt>readOnly &#60;boolean&#62;</dt>
       
   282          *    <dd>Whether or not the attribute is read only. Attributes having readOnly set to true
       
   283          *        cannot be modified by invoking the set method.</dd>
       
   284          *
       
   285          *    <dt>writeOnce &#60;boolean&#62;</dt>
       
   286          *    <dd>Whether or not the attribute is "write once". Attributes having writeOnce set to true, 
       
   287          *        can only have their values set once, be it through the default configuration, 
       
   288          *        constructor configuration arguments, or by invoking set.</dd>
       
   289          *
       
   290          *    <dt>setter &#60;Function&#62;</dt>
       
   291          *    <dd>The setter function used to massage or normalize the value passed to the set method for the attribute. 
       
   292          *    The value returned by the setter will be the final stored value. Returning
       
   293          *    <a href="#property_Attribute.INVALID_VALUE">Attribute.INVALID_VALUE</a>, from the setter will prevent
       
   294          *    the value from being stored.</dd>
       
   295          *
       
   296          *    <dt>getter &#60;Function&#62;</dt>
       
   297          *    <dd>The getter function used to massage or normalize the value returned by the get method for the attribute.
       
   298          *    The value returned by the getter function is the value which will be returned to the user when they 
       
   299          *    invoke get.</dd>
       
   300          *
       
   301          *    <dt>validator &#60;Function&#62;</dt>
       
   302          *    <dd>The validator function invoked prior to setting the stored value. Returning
       
   303          *    false from the validator function will prevent the value from being stored.</dd>
       
   304          *    
       
   305          *    <dt>broadcast &#60;int&#62;</dt>
       
   306          *    <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 
       
   307          *    valid values. By default attribute change events are not broadcast.</dd>
       
   308          *
       
   309          *    <dt>lazyAdd &#60;boolean&#62;</dt>
       
   310          *    <dd>Whether or not to delay initialization of the attribute until the first call to get/set it. 
       
   311          *    This flag can be used to over-ride lazy initialization on a per attribute basis, when adding multiple attributes through 
       
   312          *    the <a href="#method_addAttrs">addAttrs</a> method.</dd>
       
   313          *
       
   314          * </dl>
       
   315          *
       
   316          * <p>The setter, getter and validator are invoked with the value and name passed in as the first and second arguments, and with
       
   317          * the context ("this") set to the host object.</p>
       
   318          *
       
   319          * <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>
       
   320          * 
       
   321          * @method addAttr
       
   322          *
       
   323          * @param {String} name The name of the attribute.
       
   324          * @param {Object} config An object with attribute configuration property/value pairs, specifying the configuration for the attribute.
       
   325          *
       
   326          * <p>
       
   327          * <strong>NOTE:</strong> The configuration object is modified when adding an attribute, so if you need 
       
   328          * to protect the original values, you will need to merge the object.
       
   329          * </p>
       
   330          *
       
   331          * @param {boolean} lazy (optional) Whether or not to add this attribute lazily (on the first call to get/set). 
       
   332          *
       
   333          * @return {Object} A reference to the host object.
       
   334          *
       
   335          * @chainable
       
   336          */
       
   337         addAttr: function(name, config, lazy) {
       
   338 
       
   339             Y.log('Adding attribute: ' + name, 'info', 'attribute');
       
   340 
       
   341             var host = this, // help compression
       
   342                 state = host._state,
       
   343                 value,
       
   344                 hasValue;
       
   345 
       
   346             lazy = (LAZY_ADD in config) ? config[LAZY_ADD] : lazy;
       
   347 
       
   348             if (lazy && !host.attrAdded(name)) {
       
   349                 state.add(name, LAZY, config || {});
       
   350                 state.add(name, ADDED, true);
       
   351             } else {
       
   352 
       
   353                 if (host.attrAdded(name) && !state.get(name, IS_LAZY_ADD)) { Y.log('Attribute: ' + name + ' already exists. Cannot add it again without removing it first', 'warn', 'attribute'); }
       
   354 
       
   355                 if (!host.attrAdded(name) || state.get(name, IS_LAZY_ADD)) {
       
   356 
       
   357                     config = config || {};
       
   358 
       
   359                     hasValue = (VALUE in config);
       
   360 
       
   361                     if (config.readOnly && !hasValue) { Y.log('readOnly attribute: ' + name + ', added without an initial value. Value will be set on initial call to set', 'warn', 'attribute');}
       
   362 
       
   363                     if(hasValue) {
       
   364                         // We'll go through set, don't want to set value in _state directly
       
   365                         value = config.value;
       
   366                         delete config.value;
       
   367                     }
       
   368 
       
   369                     config.added = true;
       
   370                     config.initializing = true;
       
   371 
       
   372                     state.addAll(name, config);
       
   373 
       
   374                     if (hasValue) {
       
   375                         // Go through set, so that raw values get normalized/validated
       
   376                         host.set(name, value);
       
   377                     }
       
   378 
       
   379                     state.remove(name, INITIALIZING);
       
   380                 }
       
   381             }
       
   382 
       
   383             return host;
       
   384         },
       
   385 
       
   386         /**
       
   387          * Checks if the given attribute has been added to the host
       
   388          *
       
   389          * @method attrAdded
       
   390          * @param {String} name The name of the attribute to check.
       
   391          * @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.
       
   392          */
       
   393         attrAdded: function(name) {
       
   394             return !!this._state.get(name, ADDED);
       
   395         },
       
   396 
       
   397         /**
       
   398          * Updates the configuration of an attribute which has already been added.
       
   399          * <p>
       
   400          * The properties which can be modified through this interface are limited
       
   401          * to the following subset of attributes, which can be safely modified
       
   402          * after a value has already been set on the attribute: readOnly, writeOnce, 
       
   403          * broadcast and getter.
       
   404          * </p>
       
   405          * @method modifyAttr
       
   406          * @param {String} name The name of the attribute whose configuration is to be updated.
       
   407          * @param {Object} config An object with configuration property/value pairs, specifying the configuration properties to modify.
       
   408          */
       
   409         modifyAttr: function(name, config) {
       
   410             var host = this, // help compression
       
   411                 prop, state;
       
   412 
       
   413             if (host.attrAdded(name)) {
       
   414 
       
   415                 if (host._isLazyAttr(name)) {
       
   416                     host._addLazyAttr(name);
       
   417                 }
       
   418 
       
   419                 state = host._state;
       
   420                 for (prop in config) {
       
   421                     if (MODIFIABLE[prop] && config.hasOwnProperty(prop)) {
       
   422                         state.add(name, prop, config[prop]);
       
   423 
       
   424                         // If we reconfigured broadcast, need to republish
       
   425                         if (prop === BROADCAST) {
       
   426                             state.remove(name, PUBLISHED);
       
   427                         }
       
   428                     }
       
   429                 }
       
   430             }
       
   431 
       
   432             if (!host.attrAdded(name)) {Y.log('Attribute modifyAttr:' + name + ' has not been added. Use addAttr to add the attribute', 'warn', 'attribute');}
       
   433         },
       
   434 
       
   435         /**
       
   436          * Removes an attribute from the host object
       
   437          *
       
   438          * @method removeAttr
       
   439          * @param {String} name The name of the attribute to be removed.
       
   440          */
       
   441         removeAttr: function(name) {
       
   442             this._state.removeAll(name);
       
   443         },
       
   444 
       
   445         /**
       
   446          * Returns the current value of the attribute. If the attribute
       
   447          * has been configured with a 'getter' function, this method will delegate
       
   448          * to the 'getter' to obtain the value of the attribute.
       
   449          *
       
   450          * @method get
       
   451          *
       
   452          * @param {String} name The name of the attribute. If the value of the attribute is an Object, 
       
   453          * dot notation can be used to obtain the value of a property of the object (e.g. <code>get("x.y.z")</code>)
       
   454          *
       
   455          * @return {Any} The value of the attribute
       
   456          */
       
   457         get : function(name) {
       
   458             return this._getAttr(name);
       
   459         },
       
   460 
       
   461         /**
       
   462          * Checks whether or not the attribute is one which has been
       
   463          * added lazily and still requires initialization.
       
   464          *
       
   465          * @method _isLazyAttr
       
   466          * @private
       
   467          * @param {String} name The name of the attribute
       
   468          * @return {boolean} true if it's a lazily added attribute, false otherwise.
       
   469          */
       
   470         _isLazyAttr: function(name) {
       
   471             return this._state.get(name, LAZY);
       
   472         },
       
   473 
       
   474         /**
       
   475          * Finishes initializing an attribute which has been lazily added.
       
   476          *
       
   477          * @method _addLazyAttr
       
   478          * @private
       
   479          * @param {Object} name The name of the attribute
       
   480          */
       
   481         _addLazyAttr: function(name) {
       
   482             var state = this._state,
       
   483                 lazyCfg = state.get(name, LAZY);
       
   484 
       
   485             state.add(name, IS_LAZY_ADD, true);
       
   486             state.remove(name, LAZY);
       
   487             this.addAttr(name, lazyCfg);
       
   488         },
       
   489 
       
   490         /**
       
   491          * Sets the value of an attribute.
       
   492          *
       
   493          * @method set
       
   494          * @chainable
       
   495          *
       
   496          * @param {String} name The name of the attribute. If the 
       
   497          * current value of the attribute is an Object, dot notation can be used
       
   498          * to set the value of a property within the object (e.g. <code>set("x.y.z", 5)</code>).
       
   499          *
       
   500          * @param {Any} value The value to set the attribute to.
       
   501          *
       
   502          * @param {Object} opts (Optional) Optional event data to be mixed into
       
   503          * the event facade passed to subscribers of the attribute's change event. This 
       
   504          * can be used as a flexible way to identify the source of a call to set, allowing 
       
   505          * the developer to distinguish between set called internally by the host, vs. 
       
   506          * set called externally by the application developer.
       
   507          *
       
   508          * @return {Object} A reference to the host object.
       
   509          */
       
   510         set : function(name, val, opts) {
       
   511             return this._setAttr(name, val, opts);
       
   512         },
       
   513 
       
   514         /**
       
   515          * Resets the attribute (or all attributes) to its initial value, as long as
       
   516          * the attribute is not readOnly, or writeOnce.
       
   517          *
       
   518          * @method reset
       
   519          * @param {String} name Optional. The name of the attribute to reset.  If omitted, all attributes are reset.
       
   520          * @return {Object} A reference to the host object.
       
   521          * @chainable
       
   522          */
       
   523         reset : function(name) {
       
   524             var host = this,  // help compression
       
   525                 added;
       
   526 
       
   527             if (name) {
       
   528                 if (host._isLazyAttr(name)) {
       
   529                     host._addLazyAttr(name);
       
   530                 }
       
   531                 host.set(name, host._state.get(name, INIT_VALUE));
       
   532             } else {
       
   533                 added = host._state.data.added;
       
   534                 Y.each(added, function(v, n) {
       
   535                     host.reset(n);
       
   536                 }, host);
       
   537             }
       
   538             return host;
       
   539         },
       
   540 
       
   541         /**
       
   542          * Allows setting of readOnly/writeOnce attributes. See <a href="#method_set">set</a> for argument details.
       
   543          *
       
   544          * @method _set
       
   545          * @protected
       
   546          * @chainable
       
   547          * 
       
   548          * @param {String} name The name of the attribute.
       
   549          * @param {Any} val The value to set the attribute to.
       
   550          * @param {Object} opts (Optional) Optional event data to be mixed into
       
   551          * the event facade passed to subscribers of the attribute's change event.
       
   552          * @return {Object} A reference to the host object.
       
   553          */
       
   554         _set : function(name, val, opts) {
       
   555             return this._setAttr(name, val, opts, true);
       
   556         },
       
   557 
       
   558         /**
       
   559          * Provides the common implementation for the public get method,
       
   560          * allowing Attribute hosts to over-ride either method.
       
   561          *
       
   562          * See <a href="#method_get">get</a> for argument details.
       
   563          *
       
   564          * @method _getAttr
       
   565          * @protected
       
   566          * @chainable
       
   567          *
       
   568          * @param {String} name The name of the attribute.
       
   569          * @return {Any} The value of the attribute.
       
   570          */
       
   571         _getAttr : function(name) {
       
   572             var host = this, // help compression
       
   573                 fullName = name,
       
   574                 state = host._state,
       
   575                 path,
       
   576                 getter,
       
   577                 val,
       
   578                 cfg;
       
   579 
       
   580             if (name.indexOf(DOT) !== -1) {
       
   581                 path = name.split(DOT);
       
   582                 name = path.shift();
       
   583             }
       
   584 
       
   585             // On Demand - Should be rare - handles out of order valueFn references
       
   586             if (host._tCfgs && host._tCfgs[name]) {
       
   587                 cfg = {};
       
   588                 cfg[name] = host._tCfgs[name];
       
   589                 delete host._tCfgs[name];
       
   590                 host._addAttrs(cfg, host._tVals);
       
   591             }
       
   592 
       
   593             // Lazy Init
       
   594             if (host._isLazyAttr(name)) {
       
   595                 host._addLazyAttr(name);
       
   596             }
       
   597 
       
   598             val = host._getStateVal(name);
       
   599             getter = state.get(name, GETTER);
       
   600 
       
   601             val = (getter) ? getter.call(host, val, fullName) : val;
       
   602             val = (path) ? O.getValue(val, path) : val;
       
   603 
       
   604             return val;
       
   605         },
       
   606 
       
   607         /**
       
   608          * Provides the common implementation for the public set and protected _set methods.
       
   609          *
       
   610          * See <a href="#method_set">set</a> for argument details.
       
   611          *
       
   612          * @method _setAttr
       
   613          * @protected
       
   614          * @chainable
       
   615          *
       
   616          * @param {String} name The name of the attribute.
       
   617          * @param {Any} value The value to set the attribute to.
       
   618          * @param {Object} opts (Optional) Optional event data to be mixed into
       
   619          * the event facade passed to subscribers of the attribute's change event.
       
   620          * @param {boolean} force If true, allows the caller to set values for 
       
   621          * readOnly or writeOnce attributes which have already been set.
       
   622          *
       
   623          * @return {Object} A reference to the host object.
       
   624          */
       
   625         _setAttr : function(name, val, opts, force) {
       
   626             var allowSet = true,
       
   627                 state = this._state,
       
   628                 stateProxy = this._stateProxy,
       
   629                 data = state.data,
       
   630                 initialSet,
       
   631                 strPath,
       
   632                 path,
       
   633                 currVal;
       
   634 
       
   635             if (name.indexOf(DOT) !== -1) {
       
   636                 strPath = name;
       
   637                 path = name.split(DOT);
       
   638                 name = path.shift();
       
   639             }
       
   640 
       
   641             if (this._isLazyAttr(name)) {
       
   642                 this._addLazyAttr(name);
       
   643             }
       
   644 
       
   645             initialSet = (!data.value || !(name in data.value));
       
   646 
       
   647             if (stateProxy && name in stateProxy && !this._state.get(name, BYPASS_PROXY)) {
       
   648                 // 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? 
       
   649                 initialSet = false;
       
   650             }
       
   651 
       
   652             if (this._requireAddAttr && !this.attrAdded(name)) {
       
   653                 Y.log('Set attribute:' + name + ', aborted; Attribute is not configured', 'warn', 'attribute');
       
   654             } else {
       
   655 
       
   656                 if (!initialSet && !force) {
       
   657 
       
   658                     if (state.get(name, WRITE_ONCE)) {
       
   659                         Y.log('Set attribute:' + name + ', aborted; Attribute is writeOnce', 'warn', 'attribute');
       
   660                         allowSet = false;
       
   661                     }
       
   662 
       
   663                     if (state.get(name, READ_ONLY)) {
       
   664                         Y.log('Set attribute:' + name + ', aborted; Attribute is readOnly', 'warn', 'attribute');
       
   665                         allowSet = false;
       
   666                     }
       
   667                 }
       
   668 
       
   669                 if (allowSet) {
       
   670                     // Don't need currVal if initialSet (might fail in custom getter if it always expects a non-undefined/non-null value)
       
   671                     if (!initialSet) {
       
   672                         currVal =  this.get(name);
       
   673                     }
       
   674 
       
   675                     if (path) {
       
   676                        val = O.setValue(Y.clone(currVal), path, val);
       
   677 
       
   678                        if (val === undefined) {
       
   679                            Y.log('Set attribute path:' + strPath + ', aborted; Path is invalid', 'warn', 'attribute');
       
   680                            allowSet = false;
       
   681                        }
       
   682                     }
       
   683 
       
   684                     if (allowSet) {
       
   685                         if (state.get(name, INITIALIZING)) {
       
   686                             this._setAttrVal(name, strPath, currVal, val);
       
   687                         } else {
       
   688                             this._fireAttrChange(name, strPath, currVal, val, opts);
       
   689                         }
       
   690                     }
       
   691                 }
       
   692             }
       
   693 
       
   694             return this;
       
   695         },
       
   696 
       
   697         /**
       
   698          * Utility method to help setup the event payload and fire the attribute change event.
       
   699          * 
       
   700          * @method _fireAttrChange
       
   701          * @private
       
   702          * @param {String} attrName The name of the attribute
       
   703          * @param {String} subAttrName The full path of the property being changed, 
       
   704          * if this is a sub-attribute value being change. Otherwise null.
       
   705          * @param {Any} currVal The current value of the attribute
       
   706          * @param {Any} newVal The new value of the attribute
       
   707          * @param {Object} opts Any additional event data to mix into the attribute change event's event facade.
       
   708          */
       
   709         _fireAttrChange : function(attrName, subAttrName, currVal, newVal, opts) {
       
   710             var host = this,
       
   711                 eventName = attrName + CHANGE,
       
   712                 state = host._state,
       
   713                 facade;
       
   714 
       
   715             if (!state.get(attrName, PUBLISHED)) {
       
   716                 host.publish(eventName, {
       
   717                     queuable:false, 
       
   718                     defaultFn:host._defAttrChangeFn, 
       
   719                     silent:true,
       
   720                     broadcast : state.get(attrName, BROADCAST)
       
   721                 });
       
   722                 state.add(attrName, PUBLISHED, true);
       
   723             }
       
   724 
       
   725             facade = (opts) ? Y.merge(opts) : host._ATTR_E_FACADE;
       
   726 
       
   727             facade.type = eventName;
       
   728             facade.attrName = attrName;
       
   729             facade.subAttrName = subAttrName;
       
   730             facade.prevVal = currVal;
       
   731             facade.newVal = newVal;
       
   732 
       
   733             host.fire(facade);
       
   734         },
       
   735 
       
   736         /**
       
   737          * Default function for attribute change events.
       
   738          *
       
   739          * @private
       
   740          * @method _defAttrChangeFn
       
   741          * @param {EventFacade} e The event object for attribute change events.
       
   742          */
       
   743         _defAttrChangeFn : function(e) {
       
   744             if (!this._setAttrVal(e.attrName, e.subAttrName, e.prevVal, e.newVal)) {
       
   745                 Y.log('State not updated and stopImmediatePropagation called for attribute: ' + e.attrName + ' , value:' + e.newVal, 'warn', 'attribute');
       
   746                 // Prevent "after" listeners from being invoked since nothing changed.
       
   747                 e.stopImmediatePropagation();
       
   748             } else {
       
   749                 e.newVal = this._getStateVal(e.attrName);
       
   750             }
       
   751         },
       
   752 
       
   753         /**
       
   754          * Gets the stored value for the attribute, from either the 
       
   755          * internal state object, or the state proxy if it exits
       
   756          * 
       
   757          * @method _getStateVal
       
   758          * @private
       
   759          * @param {String} name The name of the attribute
       
   760          * @return {Any} The stored value of the attribute
       
   761          */
       
   762         _getStateVal : function(name) {
       
   763             var stateProxy = this._stateProxy;
       
   764             return stateProxy && (name in stateProxy) && !this._state.get(name, BYPASS_PROXY) ? stateProxy[name] : this._state.get(name, VALUE);
       
   765         },
       
   766 
       
   767         /**
       
   768          * Sets the stored value for the attribute, in either the 
       
   769          * internal state object, or the state proxy if it exits
       
   770          *
       
   771          * @method _setStateVal
       
   772          * @private
       
   773          * @param {String} name The name of the attribute
       
   774          * @param {Any} value The value of the attribute
       
   775          */
       
   776         _setStateVal : function(name, value) {
       
   777             var stateProxy = this._stateProxy;
       
   778             if (stateProxy && (name in stateProxy) && !this._state.get(name, BYPASS_PROXY)) {
       
   779                 stateProxy[name] = value;
       
   780             } else {
       
   781                 this._state.add(name, VALUE, value);
       
   782             }
       
   783         },
       
   784 
       
   785         /**
       
   786          * Updates the stored value of the attribute in the privately held State object,
       
   787          * if validation and setter passes.
       
   788          *
       
   789          * @method _setAttrVal
       
   790          * @private
       
   791          * @param {String} attrName The attribute name.
       
   792          * @param {String} subAttrName The sub-attribute name, if setting a sub-attribute property ("x.y.z").
       
   793          * @param {Any} prevVal The currently stored value of the attribute.
       
   794          * @param {Any} newVal The value which is going to be stored.
       
   795          * 
       
   796          * @return {booolean} true if the new attribute value was stored, false if not.
       
   797          */
       
   798         _setAttrVal : function(attrName, subAttrName, prevVal, newVal) {
       
   799 
       
   800             var host = this,
       
   801                 allowSet = true,
       
   802                 state = host._state,
       
   803 
       
   804                 validator = state.get(attrName, VALIDATOR),
       
   805                 setter = state.get(attrName, SETTER),
       
   806                 initializing = state.get(attrName, INITIALIZING),
       
   807                 prevValRaw = this._getStateVal(attrName),
       
   808 
       
   809                 name = subAttrName || attrName,
       
   810                 retVal,
       
   811                 valid;
       
   812 
       
   813             if (validator) {
       
   814                 valid = validator.call(host, newVal, name);
       
   815 
       
   816                 if (!valid && initializing) {
       
   817                     newVal = state.get(attrName, DEF_VALUE);
       
   818                     valid = true; // Assume it's valid, for perf.
       
   819                 }
       
   820             }
       
   821 
       
   822             if (!validator || valid) {
       
   823                 if (setter) {
       
   824                     retVal = setter.call(host, newVal, name);
       
   825 
       
   826                     if (retVal === INVALID_VALUE) {
       
   827                         Y.log('Attribute: ' + attrName + ', setter returned Attribute.INVALID_VALUE for value:' + newVal, 'warn', 'attribute');
       
   828                         allowSet = false;
       
   829                     } else if (retVal !== undefined){
       
   830                         Y.log('Attribute: ' + attrName + ', raw value: ' + newVal + ' modified by setter to:' + retVal, 'info', 'attribute');
       
   831                         newVal = retVal;
       
   832                     }
       
   833                 }
       
   834 
       
   835                 if (allowSet) {
       
   836                     if(!subAttrName && (newVal === prevValRaw) && !Lang.isObject(newVal)) {
       
   837                         Y.log('Attribute: ' + attrName + ', value unchanged:' + newVal, 'warn', 'attribute');
       
   838                         allowSet = false;
       
   839                     } else {
       
   840                         // Store value
       
   841                         if (state.get(attrName, INIT_VALUE) === undefined) {
       
   842                             state.add(attrName, INIT_VALUE, newVal);
       
   843                         }
       
   844                         host._setStateVal(attrName, newVal);
       
   845                     }
       
   846                 }
       
   847 
       
   848             } else {
       
   849                 Y.log('Attribute:' + attrName + ', Validation failed for value:' + newVal, 'warn', 'attribute');
       
   850                 allowSet = false;
       
   851             }
       
   852 
       
   853             return allowSet;
       
   854         },
       
   855 
       
   856         /**
       
   857          * Sets multiple attribute values.
       
   858          *
       
   859          * @method setAttrs
       
   860          * @param {Object} attrs  An object with attributes name/value pairs.
       
   861          * @return {Object} A reference to the host object.
       
   862          * @chainable
       
   863          */
       
   864         setAttrs : function(attrs, opts) {
       
   865             return this._setAttrs(attrs, opts);
       
   866         },
       
   867 
       
   868         /**
       
   869          * Implementation behind the public setAttrs method, to set multiple attribute values.
       
   870          *
       
   871          * @method _setAttrs
       
   872          * @protected
       
   873          * @param {Object} attrs  An object with attributes name/value pairs.
       
   874          * @return {Object} A reference to the host object.
       
   875          * @chainable
       
   876          */
       
   877         _setAttrs : function(attrs, opts) {
       
   878             for (var attr in attrs) {
       
   879                 if ( attrs.hasOwnProperty(attr) ) {
       
   880                     this.set(attr, attrs[attr]);
       
   881                 }
       
   882             }
       
   883             return this;
       
   884         },
       
   885 
       
   886         /**
       
   887          * Gets multiple attribute values.
       
   888          *
       
   889          * @method getAttrs
       
   890          * @param {Array | boolean} attrs Optional. An array of attribute names. If omitted, all attribute values are
       
   891          * returned. If set to true, all attributes modified from their initial values are returned.
       
   892          * @return {Object} An object with attribute name/value pairs.
       
   893          */
       
   894         getAttrs : function(attrs) {
       
   895             return this._getAttrs(attrs);
       
   896         },
       
   897 
       
   898         /**
       
   899          * Implementation behind the public getAttrs method, to get multiple attribute values.
       
   900          *
       
   901          * @method _getAttrs
       
   902          * @protected
       
   903          * @param {Array | boolean} attrs Optional. An array of attribute names. If omitted, all attribute values are
       
   904          * returned. If set to true, all attributes modified from their initial values are returned.
       
   905          * @return {Object} An object with attribute name/value pairs.
       
   906          */
       
   907         _getAttrs : function(attrs) {
       
   908             var host = this,
       
   909                 o = {}, 
       
   910                 i, l, attr, val,
       
   911                 modifiedOnly = (attrs === true);
       
   912 
       
   913             attrs = (attrs && !modifiedOnly) ? attrs : O.keys(host._state.data.added);
       
   914 
       
   915             for (i = 0, l = attrs.length; i < l; i++) {
       
   916                 // Go through get, to honor cloning/normalization
       
   917                 attr = attrs[i];
       
   918                 val = host.get(attr);
       
   919 
       
   920                 if (!modifiedOnly || host._getStateVal(attr) != host._state.get(attr, INIT_VALUE)) {
       
   921                     o[attr] = host.get(attr); 
       
   922                 }
       
   923             }
       
   924 
       
   925             return o;
       
   926         },
       
   927 
       
   928         /**
       
   929          * Configures a group of attributes, and sets initial values.
       
   930          *
       
   931          * <p>
       
   932          * <strong>NOTE:</strong> This method does not isolate the configuration object by merging/cloning. 
       
   933          * The caller is responsible for merging/cloning the configuration object if required.
       
   934          * </p>
       
   935          *
       
   936          * @method addAttrs
       
   937          * @chainable
       
   938          *
       
   939          * @param {Object} cfgs An object with attribute name/configuration pairs.
       
   940          * @param {Object} values An object with attribute name/value pairs, defining the initial values to apply.
       
   941          * Values defined in the cfgs argument will be over-written by values in this argument unless defined as read only.
       
   942          * @param {boolean} lazy Whether or not to delay the intialization of these attributes until the first call to get/set.
       
   943          * Individual attributes can over-ride this behavior by defining a lazyAdd configuration property in their configuration.
       
   944          * See <a href="#method_addAttr">addAttr</a>.
       
   945          * 
       
   946          * @return {Object} A reference to the host object.
       
   947          */
       
   948         addAttrs : function(cfgs, values, lazy) {
       
   949             var host = this; // help compression
       
   950             if (cfgs) {
       
   951                 host._tCfgs = cfgs;
       
   952                 host._tVals = host._normAttrVals(values);
       
   953                 host._addAttrs(cfgs, host._tVals, lazy);
       
   954                 host._tCfgs = host._tVals = null;
       
   955             }
       
   956 
       
   957             return host;
       
   958         },
       
   959 
       
   960         /**
       
   961          * Implementation behind the public addAttrs method. 
       
   962          * 
       
   963          * This method is invoked directly by get if it encounters a scenario 
       
   964          * in which an attribute's valueFn attempts to obtain the 
       
   965          * value an attribute in the same group of attributes, which has not yet 
       
   966          * been added (on demand initialization).
       
   967          *
       
   968          * @method _addAttrs
       
   969          * @private
       
   970          * @param {Object} cfgs An object with attribute name/configuration pairs.
       
   971          * @param {Object} values An object with attribute name/value pairs, defining the initial values to apply.
       
   972          * Values defined in the cfgs argument will be over-written by values in this argument unless defined as read only.
       
   973          * @param {boolean} lazy Whether or not to delay the intialization of these attributes until the first call to get/set.
       
   974          * Individual attributes can over-ride this behavior by defining a lazyAdd configuration property in their configuration.
       
   975          * See <a href="#method_addAttr">addAttr</a>.
       
   976          */
       
   977         _addAttrs : function(cfgs, values, lazy) {
       
   978             var host = this, // help compression
       
   979                 attr,
       
   980                 attrCfg,
       
   981                 value;
       
   982 
       
   983             for (attr in cfgs) {
       
   984                 if (cfgs.hasOwnProperty(attr)) {
       
   985 
       
   986                     // Not Merging. Caller is responsible for isolating configs
       
   987                     attrCfg = cfgs[attr];
       
   988                     attrCfg.defaultValue = attrCfg.value;
       
   989 
       
   990                     // Handle simple, complex and user values, accounting for read-only
       
   991                     value = host._getAttrInitVal(attr, attrCfg, host._tVals);
       
   992 
       
   993                     if (value !== undefined) {
       
   994                         attrCfg.value = value;
       
   995                     }
       
   996 
       
   997                     if (host._tCfgs[attr]) {
       
   998                         delete host._tCfgs[attr];
       
   999                     }
       
  1000 
       
  1001                     host.addAttr(attr, attrCfg, lazy);
       
  1002                 }
       
  1003             }
       
  1004         },
       
  1005 
       
  1006         /**
       
  1007          * Utility method to protect an attribute configuration
       
  1008          * hash, by merging the entire object and the individual 
       
  1009          * attr config objects. 
       
  1010          *
       
  1011          * @method _protectAttrs
       
  1012          * @protected
       
  1013          * @param {Object} attrs A hash of attribute to configuration object pairs.
       
  1014          * @return {Object} A protected version of the attrs argument.
       
  1015          */
       
  1016         _protectAttrs : function(attrs) {
       
  1017             if (attrs) {
       
  1018                 attrs = Y.merge(attrs);
       
  1019                 for (var attr in attrs) {
       
  1020                     if (attrs.hasOwnProperty(attr)) {
       
  1021                         attrs[attr] = Y.merge(attrs[attr]);
       
  1022                     }
       
  1023                 }
       
  1024             }
       
  1025             return attrs;
       
  1026         },
       
  1027 
       
  1028         /**
       
  1029          * Utility method to normalize attribute values. The base implementation 
       
  1030          * simply merges the hash to protect the original.
       
  1031          *
       
  1032          * @method _normAttrVals
       
  1033          * @param {Object} valueHash An object with attribute name/value pairs
       
  1034          *
       
  1035          * @return {Object}
       
  1036          *
       
  1037          * @private
       
  1038          */
       
  1039         _normAttrVals : function(valueHash) {
       
  1040             return (valueHash) ? Y.merge(valueHash) : null;
       
  1041         },
       
  1042 
       
  1043         /**
       
  1044          * Returns the initial value of the given attribute from
       
  1045          * either the default configuration provided, or the 
       
  1046          * over-ridden value if it exists in the set of initValues 
       
  1047          * provided and the attribute is not read-only.
       
  1048          *
       
  1049          * @param {String} attr The name of the attribute
       
  1050          * @param {Object} cfg The attribute configuration object
       
  1051          * @param {Object} initValues The object with simple and complex attribute name/value pairs returned from _normAttrVals
       
  1052          *
       
  1053          * @return {Any} The initial value of the attribute.
       
  1054          *
       
  1055          * @method _getAttrInitVal
       
  1056          * @private
       
  1057          */
       
  1058         _getAttrInitVal : function(attr, cfg, initValues) {
       
  1059 
       
  1060             // init value is provided by the user if it exists, else, provided by the config
       
  1061             var val = (!cfg[READ_ONLY] && initValues && initValues.hasOwnProperty(attr)) ?
       
  1062                             val = initValues[attr] :
       
  1063                             (cfg[VALUE_FN]) ?
       
  1064                                 cfg[VALUE_FN].call(this) : 
       
  1065                                 cfg[VALUE];
       
  1066 
       
  1067             Y.log('initValue for ' + attr + ':' + val, 'info', 'attribute');
       
  1068 
       
  1069             return val;
       
  1070         }
       
  1071     };
       
  1072 
       
  1073     // Basic prototype augment - no lazy constructor invocation.
       
  1074     Y.mix(Attribute, EventTarget, false, null, 1);
       
  1075 
       
  1076     Y.Attribute = Attribute;
       
  1077 
       
  1078 
       
  1079 }, '3.0.0' ,{requires:['event-custom']});
       
  1080 YUI.add('attribute-complex', function(Y) {
       
  1081 
       
  1082     /**
       
  1083      * Adds support for attribute providers to handle complex attributes in the constructor
       
  1084      *
       
  1085      * @module attribute
       
  1086      * @submodule attribute-complex
       
  1087      * @for Attribute
       
  1088      */
       
  1089 
       
  1090     var O = Y.Object,
       
  1091         DOT = ".";
       
  1092 
       
  1093     Y.Attribute.Complex = function() {};
       
  1094     Y.Attribute.Complex.prototype = {
       
  1095 
       
  1096         /**
       
  1097          * Utility method to split out simple attribute name/value pairs ("x") 
       
  1098          * from complex attribute name/value pairs ("x.y.z"), so that complex
       
  1099          * attributes can be keyed by the top level attribute name.
       
  1100          *
       
  1101          * @method _normAttrVals
       
  1102          * @param {Object} valueHash An object with attribute name/value pairs
       
  1103          *
       
  1104          * @return {Object} An object literal with 2 properties - "simple" and "complex",
       
  1105          * containing simple and complex attribute values respectively keyed 
       
  1106          * by the top level attribute name, or null, if valueHash is falsey.
       
  1107          *
       
  1108          * @private
       
  1109          */
       
  1110         _normAttrVals : function(valueHash) {
       
  1111             var vals = {},
       
  1112                 subvals = {},
       
  1113                 path,
       
  1114                 attr,
       
  1115                 v, k;
       
  1116 
       
  1117             if (valueHash) {
       
  1118                 for (k in valueHash) {
       
  1119                     if (valueHash.hasOwnProperty(k)) {
       
  1120                         if (k.indexOf(DOT) !== -1) {
       
  1121                             path = k.split(DOT);
       
  1122                             attr = path.shift();
       
  1123                             v = subvals[attr] = subvals[attr] || [];
       
  1124                             v[v.length] = {
       
  1125                                 path : path, 
       
  1126                                 value: valueHash[k]
       
  1127                             };
       
  1128                         } else {
       
  1129                             vals[k] = valueHash[k];
       
  1130                         }
       
  1131                     }
       
  1132                 }
       
  1133                 return { simple:vals, complex:subvals };
       
  1134             } else {
       
  1135                 return null;
       
  1136             }
       
  1137         },
       
  1138 
       
  1139         /**
       
  1140          * Returns the initial value of the given attribute from
       
  1141          * either the default configuration provided, or the 
       
  1142          * over-ridden value if it exists in the set of initValues 
       
  1143          * provided and the attribute is not read-only.
       
  1144          *
       
  1145          * @param {String} attr The name of the attribute
       
  1146          * @param {Object} cfg The attribute configuration object
       
  1147          * @param {Object} initValues The object with simple and complex attribute name/value pairs returned from _normAttrVals
       
  1148          *
       
  1149          * @return {Any} The initial value of the attribute.
       
  1150          *
       
  1151          * @method _getAttrInitVal
       
  1152          * @private
       
  1153          */
       
  1154         _getAttrInitVal : function(attr, cfg, initValues) {
       
  1155 
       
  1156             var val = (cfg.valueFn) ? cfg.valueFn.call(this) : cfg.value,
       
  1157                 simple,
       
  1158                 complex,
       
  1159                 i,
       
  1160                 l,
       
  1161                 path,
       
  1162                 subval,
       
  1163                 subvals;
       
  1164 
       
  1165             if (!cfg.readOnly && initValues) {
       
  1166 
       
  1167                 // Simple Attributes
       
  1168                 simple = initValues.simple;
       
  1169                 if (simple && simple.hasOwnProperty(attr)) {
       
  1170                     val = simple[attr];
       
  1171                 }
       
  1172 
       
  1173                 // Complex Attributes (complex values applied, after simple, incase both are set)
       
  1174                 complex = initValues.complex;
       
  1175                 if (complex && complex.hasOwnProperty(attr)) {
       
  1176                     subvals = complex[attr];
       
  1177                     for (i = 0, l = subvals.length; i < l; ++i) {
       
  1178                         path = subvals[i].path;
       
  1179                         subval = subvals[i].value;
       
  1180                         O.setValue(val, path, subval);
       
  1181                     }
       
  1182                 }
       
  1183             }
       
  1184 
       
  1185             return val;
       
  1186         }
       
  1187     };
       
  1188 
       
  1189     Y.mix(Y.Attribute, Y.Attribute.Complex, true, null, 1);
       
  1190 
       
  1191 
       
  1192 }, '3.0.0' ,{requires:['attribute-base']});
       
  1193 
       
  1194 
       
  1195 YUI.add('attribute', function(Y){}, '3.0.0' ,{use:['attribute-base', 'attribute-complex']});
       
  1196