/**
+ * The base-build submodule provides Base.build functionality, which
+ * can be used to create custom classes, by aggregating extensions onto
+ * a main class.
+ *
+ * @module base
+ * @submodule base-build
+ * @for Base
+ */
+
+ var Base = Y.Base,
+ L = Y.Lang;
+
+ /**
+ * The build configuration for the Base class.
+ *
+ * Defines the static fields which need to be aggregated
+ * when the Base class is used as the main class passed to
+ * the <a href="#method_Base.build">Base.build</a> method.
+ *
+ * @property Base._buildCfg
+ * @type Object
+ * @static
+ * @final
+ * @private
+ */
+ Base._buildCfg = {
+ aggregates : ["ATTRS", "_PLUG", "_UNPLUG"]
+ };
+
+ /**
+ * <p>
+ * Builds a custom constructor function (class) from the
+ * main function, and array of extension functions (classes)
+ * provided. The NAME field for the constructor function is
+ * defined by the first argument passed in.
+ * </p>
+ * <p>
+ * The cfg object supports the following properties
+ * </p>
+ * <dl>
+ * <dt>dynamic <boolean></dt>
+ * <dd>
+ * <p>If true (default), a completely new class
+ * is created which extends the main class, and acts as the
+ * host on which the extension classes are augmented.</p>
+ * <p>If false, the extensions classes are augmented directly to
+ * the main class, modifying the main class' prototype.</p>
+ * </dd>
+ * <dt>aggregates <String[]></dt>
+ * <dd>An array of static property names, which will get aggregated
+ * on to the built class, in addition to the default properties build
+ * will always aggregate as defined by the main class' static _buildCfg
+ * property.
+ * </dd>
+ * </dl>
+ *
+ * @method Base.build
+ * @static
+ * @param {Function} name The name of the new class. Used to defined the NAME property for the new class.
+ * @param {Function} main The main class on which to base the built class
+ * @param {Function[]} extensions The set of extension classes which will be
+ * augmented/aggregated to the built class.
+ * @param {Object} cfg Optional. Build configuration for the class (see description).
+ * @return {Function} A custom class, created from the provided main and extension classes
+ */
+ Base.build = function(name, main, extensions, cfg) {
+
+ var build = Base.build,
+ builtClass = build._getClass(main, cfg),
+ aggregates = build._getAggregates(main, cfg),
+ dynamic = builtClass._yuibuild.dynamic,
+ i, l, val, extClass;
+
+ // Shallow isolate aggregates
+ if (dynamic) {
+ if (aggregates) {
+ for (i = 0, l = aggregates.length; i < l; ++i) {
+ val = aggregates[i];
+ if (main.hasOwnProperty(val)) {
+ builtClass[val] = L.isArray(main[val]) ? [] : {};
+ }
+ }
+ Y.aggregate(builtClass, main, true, aggregates);
+ }
+ }
+
+ // Augment/Aggregate
+ for (i = 0, l = extensions.length; i < l; i++) {
+ extClass = extensions[i];
+
+ if (aggregates) {
+ Y.aggregate(builtClass, extClass, true, aggregates);
+ }
+
+ // Old augment
+ Y.mix(builtClass, extClass, true, null, 1);
+
+ builtClass._yuibuild.exts.push(extClass);
+ }
+
+ builtClass.prototype.hasImpl = build._hasImpl;
+
+ if (dynamic) {
+ builtClass.NAME = name;
+ builtClass.prototype.constructor = builtClass;
+ }
+
+ return builtClass;
+ };
+
+ Y.mix(Base.build, {
+
+ _template: function(main) {
+
+ function BuiltClass() {
+
+ BuiltClass.superclass.constructor.apply(this, arguments);
+
+ var f = BuiltClass._yuibuild.exts,
+ l = f.length,
+ i;
+
+ for (i = 0; i < l; i++) {
+ f[i].apply(this, arguments);
+ }
+
+ return this;
+ }
+ Y.extend(BuiltClass, main);
+
+ return BuiltClass;
+ },
+
+ _hasImpl : function(extClass) {
+ var classes = this._getClasses();
+ for (var i = 0, l = classes.length; i < l; i++) {
+ var cls = classes[i];
+
+ if (cls._yuibuild) {
+ var exts = cls._yuibuild.exts,
+ ll = exts.length,
+ j;
+
+ for (j = 0; j < ll; j++) {
+ if (exts[j] === extClass) {
+ return true;
+ }
+ }
+ }
+ }
+ return false;
+ },
+
+ _getClass : function(main, cfg) {
+
+ var dynamic = (cfg && false === cfg.dynamic) ? false : true,
+ builtClass = (dynamic) ? Base.build._template(main) : main;
+
+ builtClass._yuibuild = {
+ id: null,
+ exts : [],
+ dynamic : dynamic
+ };
+
+ return builtClass;
+ },
+
+ _getAggregates : function(main, cfg) {
+ var aggr = [],
+ cfgAggr = (cfg && cfg.aggregates),
+ c = main,
+ classAggr;
+
+ while (c && c.prototype) {
+ classAggr = c._buildCfg && c._buildCfg.aggregates;
+ if (classAggr) {
+ aggr = aggr.concat(classAggr);
+ }
+ c = c.superclass ? c.superclass.constructor : null;
+ }
+
+ if (cfgAggr) {
+ aggr = aggr.concat(cfgAggr);
+ }
+
+ return aggr;
+ }
+ });
+