/**
+ * The base module provides the Base class, which objects requiring attribute and custom event support can extend.
+ * The module also provides two ways to reuse code - An augmentable Plugin.Host interface which provides plugin support
+ * (which is augmented to the Base class) and Base.build which provides a way to
+ * build custom classes using extensions.
+ *
+ * @module base
+ */
+
+ /**
+ * The base-base submodule provides the Base class and augmentable Plugin.Host implementation,
+ * without the extension support provided by Base.build.
+ *
+ * @module base
+ * @submodule base-base
+ */
+ var O = Y.Object,
+ DOT = ".",
+ DESTROY = "destroy",
+ INIT = "init",
+ INITIALIZED = "initialized",
+ DESTROYED = "destroyed",
+ INITIALIZER = "initializer",
+ OBJECT_CONSTRUCTOR = Object.prototype.constructor,
+ DEEP = "deep",
+ SHALLOW = "shallow",
+ VALUE = "value",
+ DESTRUCTOR = "destructor";
+
+ /**
+ * <p>
+ * A base class which objects requiring attributes and custom event support can
+ * extend. Base also handles the chaining of initializer and destructor methods across
+ * the hierarchy as part of object construction and destruction. Additionally, attributes configured
+ * through the static <a href="#property_Base.ATTRS">ATTRS</a> property for each class
+ * in the hierarchy will be initialized by Base.
+ * </p>
+ *
+ * <p>
+ * The static <a href="#property_Base.NAME">NAME</a> property of each class extending
+ * from Base will be used as the identifier for the class, and is used by Base to prefix
+ * all events fired by instances of that class.
+ * </p>
+ * @class Base
+ * @constructor
+ * @uses Attribute
+ * @uses Plugin.Host
+ *
+ * @param {Object} config Object with configuration property name/value pairs
+ */
+ function Base() {
+ Y.log('constructor called', 'life', 'base');
+
+ Y.Attribute.call(this);
+ Y.Plugin.Host.call(this);
+
+ this._silentInit = this._silentInit || false;
+ if (this._lazyAddAttrs !== false) { this._lazyAddAttrs = true; }
+
+ this.init.apply(this, arguments);
+ }
+
+ /**
+ * The list of properties which can be configured for
+ * each attribute (e.g. setter, getter, writeOnce, readOnly etc.)
+ *
+ * @property Base._ATTR_CFG
+ * @type Array
+ * @static
+ * @private
+ */
+ Base._ATTR_CFG = Y.Attribute._ATTR_CFG.concat("cloneDefaultValue");
+
+ /**
+ * <p>
+ * The string to be used to identify instances of
+ * this class, for example in prefixing events.
+ * </p>
+ * <p>
+ * Classes extending Base, should define their own
+ * static NAME property, which should be camelCase by
+ * convention (e.g. MyClass.NAME = "myClass";).
+ * </p>
+ * @property Base.NAME
+ * @type String
+ * @static
+ */
+ Base.NAME = 'base';
+
+ /**
+ * The default set of attributes which will be available for instances of this class, and
+ * their configuration. In addition to the configuration properties listed by
+ * Attribute's <a href="Attribute.html#method_addAttr">addAttr</a> method, the attribute
+ * can also be configured with a "cloneDefaultValue" property, which defines how the statically
+ * defined value field should be protected ("shallow", "deep" and false are supported values).
+ *
+ * By default if the value is an object literal or an array it will be "shallow" cloned, to
+ * protect the default value.
+ *
+ * @property Base.ATTRS
+ * @type Object
+ * @static
+ */
+ Base.ATTRS = {
+ /**
+ * Flag indicating whether or not this object
+ * has been through the init lifecycle phase.
+ *
+ * @attribute initialized
+ * @readonly
+ * @default false
+ * @type boolean
+ */
+ initialized: {
+ readOnly:true,
+ value:false
+ },
+
+ /**
+ * Flag indicating whether or not this object
+ * has been through the destroy lifecycle phase.
+ *
+ * @attribute destroyed
+ * @readonly
+ * @default false
+ * @type boolean
+ */
+ destroyed: {
+ readOnly:true,
+ value:false
+ }
+ };
+
+ Base.prototype = {
+
+ /**
+ * Init lifecycle method, invoked during construction.
+ * Fires the init event prior to setting up attributes and
+ * invoking initializers for the class hierarchy.
+ *
+ * @method init
+ * @final
+ * @chainable
+ * @param {Object} config Object with configuration property name/value pairs
+ * @return {Base} A reference to this object
+ */
+ init: function(config) {
+ Y.log('init called', 'life', 'base');
+
+ /**
+ * The string used to identify the class of this object.
+ *
+ * @deprecated Use this.constructor.NAME
+ * @property name
+ * @type String
+ */
+ this._yuievt.config.prefix = this.name = this.constructor.NAME;
+
+ /**
+ * <p>
+ * Lifecycle event for the init phase, fired prior to initialization.
+ * Invoking the preventDefault() method on the event object provided
+ * to subscribers will prevent initialization from occuring.
+ * </p>
+ * <p>
+ * Subscribers to the "after" momemt of this event, will be notified
+ * after initialization of the object is complete (and therefore
+ * cannot prevent initialization).
+ * </p>
+ *
+ * @event init
+ * @preventable _defInitFn
+ * @param {EventFacade} e Event object, with a cfg property which
+ * refers to the configuration object passed to the constructor.
+ */
+ if (!this._silentInit) {
+ this.publish(INIT, {
+ queuable:false,
+ defaultFn:this._defInitFn
+ });
+ }
+
+ if (config) {
+ if (config.on) {
+ this.on(config.on);
+ }
+ if (config.after) {
+ this.after(config.after);
+ }
+ }
+
+ if (!this._silentInit) {
+ this.fire(INIT, {cfg: config});
+ } else {
+ this._defInitFn({cfg: config});
+ }
+
+ return this;
+ },
+
+ /**
+ * <p>
+ * Destroy lifecycle method. Fires the destroy
+ * event, prior to invoking destructors for the
+ * class hierarchy.
+ * </p>
+ * <p>
+ * Subscribers to the destroy
+ * event can invoke preventDefault on the event object, to prevent destruction
+ * from proceeding.
+ * </p>
+ * @method destroy
+ * @return {Base} A reference to this object
+ * @final
+ * @chainable
+ */
+ destroy: function() {
+ Y.log('destroy called', 'life', 'base');
+
+ /**
+ * <p>
+ * Lifecycle event for the destroy phase,
+ * fired prior to destruction. Invoking the preventDefault
+ * method on the event object provided to subscribers will
+ * prevent destruction from proceeding.
+ * </p>
+ * <p>
+ * Subscribers to the "after" moment of this event, will be notified
+ * after destruction is complete (and as a result cannot prevent
+ * destruction).
+ * </p>
+ * @event destroy
+ * @preventable _defDestroyFn
+ * @param {EventFacade} e Event object
+ */
+ this.publish(DESTROY, {
+ queuable:false,
+ defaultFn: this._defDestroyFn
+ });
+ this.fire(DESTROY);
+ return this;
+ },
+
+ /**
+ * Default init event handler
+ *
+ * @method _defInitFn
+ * @param {EventFacade} e Event object, with a cfg property which
+ * refers to the configuration object passed to the constructor.
+ * @protected
+ */
+ _defInitFn : function(e) {
+ this._initHierarchy(e.cfg);
+ this._initPlugins(e.cfg);
+
+ if (!this._silentInit) {
+ this._set(INITIALIZED, true);
+ } else {
+ this._conf.add(INITIALIZED, VALUE, true);
+ }
+ },
+
+ /**
+ * Default destroy event handler
+ *
+ * @method _defDestroyFn
+ * @param {EventFacade} e Event object
+ * @protected
+ */
+ _defDestroyFn : function(e) {
+ this._destroyHierarchy();
+ this._destroyPlugins();
+ this._set(DESTROYED, true);
+ },
+
+ /**
+ * Returns the class hierarchy for this object, with Base being the last class in the array.
+ *
+ * @method _getClasses
+ * @protected
+ * @return {Function[]} An array of classes (constructor functions), making up the class hierarchy for this object.
+ * This value is cached the first time the method, or _getAttrCfgs, is invoked. Subsequent invocations return the
+ * cached value.
+ */
+ _getClasses : function() {
+ if (!this._classes) {
+ this._initHierarchyData();
+ }
+ return this._classes;
+ },
+
+ /**
+ * Returns an aggregated set of attribute configurations, by traversing the class hierarchy.
+ *
+ * @method _getAttrCfgs
+ * @protected
+ * @return {Object} The hash of attribute configurations, aggregated across classes in the hierarchy
+ * This value is cached the first time the method, or _getClasses, is invoked. Subsequent invocations return
+ * the cached value.
+ */
+ _getAttrCfgs : function() {
+ if (!this._attrs) {
+ this._initHierarchyData();
+ }
+ return this._attrs;
+ },
+
+ /**
+ * A helper method used when processing ATTRS across the class hierarchy during
+ * initialization. Returns a disposable object with the attributes defined for
+ * the provided class, extracted from the set of all attributes passed in .
+ *
+ * @method _filterAttrCfs
+ * @private
+ *
+ * @param {Function} clazz The class for which the desired attributes are required.
+ * @param {Object} allCfgs The set of all attribute configurations for this instance.
+ * Attributes will be removed from this set, if they belong to the filtered class, so
+ * that by the time all classes are processed, allCfgs will be empty.
+ *
+ * @return {Object} The set of attributes belonging to the class passed in, in the form
+ * of an object with attribute name/configuration pairs.
+ */
+ _filterAttrCfgs : function(clazz, allCfgs) {
+ var cfgs = null, attr, attrs = clazz.ATTRS;
+
+ if (attrs) {
+ for (attr in attrs) {
+ if (attrs.hasOwnProperty(attr) && allCfgs[attr]) {
+ cfgs = cfgs || {};
+ cfgs[attr] = allCfgs[attr];
+ delete allCfgs[attr];
+ }
+ }
+ }
+
+ return cfgs;
+ },
+
+ /**
+ * A helper method used by _getClasses and _getAttrCfgs, which determines both
+ * the array of classes and aggregate set of attribute configurations
+ * across the class hierarchy for the instance.
+ *
+ * @method _initHierarchyData
+ * @private
+ */
+ _initHierarchyData : function() {
+ var c = this.constructor,
+ classes = [],
+ attrs = [];
+
+ while (c) {
+ // Add to classes
+ classes[classes.length] = c;
+
+ // Add to attributes
+ if (c.ATTRS) {
+ attrs[attrs.length] = c.ATTRS;
+ }
+ c = c.superclass ? c.superclass.constructor : null;
+ }
+
+ this._classes = classes;
+ this._attrs = this._aggregateAttrs(attrs);
+ },
+
+ /**
+ * A helper method, used by _initHierarchyData to aggregate
+ * attribute configuration across the instances class hierarchy.
+ *
+ * The method will potect the attribute configuration value to protect the statically defined
+ * default value in ATTRS if required (if the value is an object literal, array or the
+ * attribute configuration has cloneDefaultValue set to shallow or deep).
+ *
+ * @method _aggregateAttrs
+ * @private
+ * @param {Array} allAttrs An array of ATTRS definitions across classes in the hierarchy
+ * (subclass first, Base last)
+ * @return {Object} The aggregate set of ATTRS definitions for the instance
+ */
+ _aggregateAttrs : function(allAttrs) {
+ var attr,
+ attrs,
+ cfg,
+ val,
+ path,
+ i,
+ clone,
+ cfgProps = Base._ATTR_CFG,
+ aggAttrs = {};
+
+ if (allAttrs) {
+ for (i = allAttrs.length-1; i >= 0; --i) {
+ attrs = allAttrs[i];
+
+ for (attr in attrs) {
+ if (attrs.hasOwnProperty(attr)) {
+
+ // Protect config passed in
+ cfg = Y.mix({}, attrs[attr], true, cfgProps);
+
+ val = cfg.value;
+ clone = cfg.cloneDefaultValue;
+
+ if (val) {
+ if ( (clone === undefined && (OBJECT_CONSTRUCTOR === val.constructor || L.isArray(val))) || clone === DEEP || clone === true) {
+ Y.log('Cloning default value for attribute:' + attr, 'info', 'base');
+ cfg.value = Y.clone(val);
+ } else if (clone === SHALLOW) {
+ Y.log('Merging default value for attribute:' + attr, 'info', 'base');
+ cfg.value = Y.merge(val);
+ }
+ // else if (clone === false), don't clone the static default value.
+ // It's intended to be used by reference.
+ }
+
+ path = null;
+ if (attr.indexOf(DOT) !== -1) {
+ path = attr.split(DOT);
+ attr = path.shift();
+ }
+
+ if (path && aggAttrs[attr] && aggAttrs[attr].value) {
+ O.setValue(aggAttrs[attr].value, path, val);
+ } else if (!path){
+ if (!aggAttrs[attr]) {
+ aggAttrs[attr] = cfg;
+ } else {
+ Y.mix(aggAttrs[attr], cfg, true, cfgProps);
+ }
+ }
+ }
+ }
+ }
+ }
+
+ return aggAttrs;
+ },
+
+ /**
+ * Initializes the class hierarchy for the instance, which includes
+ * initializing attributes for each class defined in the class's
+ * static <a href="#property_Base.ATTRS">ATTRS</a> property and
+ * invoking the initializer method on the prototype of each class in the hierarchy.
+ *
+ * @method _initHierarchy
+ * @param {Object} userVals Object with configuration property name/value pairs
+ * @private
+ */
+ _initHierarchy : function(userVals) {
+ var lazy = this._lazyAddAttrs,
+ constr,
+ constrProto,
+ ci,
+ ei,
+ el,
+ classes = this._getClasses(),
+ attrCfgs = this._getAttrCfgs();
+
+ for (ci = classes.length-1; ci >= 0; ci--) {
+
+ constr = classes[ci];
+ constrProto = constr.prototype;
+
+ if (constr._yuibuild && constr._yuibuild.exts && !constr._yuibuild.dynamic) {
+ for (ei = 0, el = constr._yuibuild.exts.length; ei < el; ei++) {
+ constr._yuibuild.exts[ei].apply(this, arguments);
+ }
+ }
+
+ this.addAttrs(this._filterAttrCfgs(constr, attrCfgs), userVals, lazy);
+
+ if (constrProto.hasOwnProperty(INITIALIZER)) {
+ constrProto.initializer.apply(this, arguments);
+ }
+ }
+ },
+
+ /**
+ * Destroys the class hierarchy for this instance by invoking
+ * the descructor method on the prototype of each class in the hierarchy.
+ *
+ * @method _destroyHierarchy
+ * @private
+ */
+ _destroyHierarchy : function() {
+ var constr,
+ constrProto,
+ ci, cl,
+ classes = this._getClasses();
+
+ for (ci = 0, cl = classes.length; ci < cl; ci++) {
+ constr = classes[ci];
+ constrProto = constr.prototype;
+ if (constrProto.hasOwnProperty(DESTRUCTOR)) {
+ constrProto.destructor.apply(this, arguments);
+ }
+ }
+ },
+
+ /**
+ * Default toString implementation. Provides the constructor NAME
+ * and the instance ID.
+ *
+ * @method toString
+ * @return {String} String representation for this object
+ */
+ toString: function() {
+ return this.constructor.NAME + "[" + Y.stamp(this) + "]";
+ }
+ };
+
+ // Straightup augment, no wrapper functions
+ Y.mix(Base, Y.Attribute, false, null, 1);
+ Y.mix(Base, PluginHost, false, null, 1);
+
+ /**
+ * Alias for <a href="Plugin.Host.html#method_Plugin.Host.plug">Plugin.Host.plug</a>. See aliased
+ * method for argument and return value details.
+ *
+ * @method Base.plug
+ * @static
+ */
+ Base.plug = PluginHost.plug;
+
+ /**
+ * Alias for <a href="Plugin.Host.html#method_Plugin.Host.unplug">Plugin.Host.unplug</a>. See the
+ * aliased method for argument and return value details.
+ *
+ * @method Base.unplug
+ * @static
+ */
+ Base.unplug = PluginHost.unplug;
+
+ // Fix constructor
+ Base.prototype.constructor = Base;
+
+ Y.Base = Base;
+