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YUI.add('widget-parent', function (Y, NAME) {

/**

 * Extension enabling a Widget to be a parent of another Widget.

 *

 * @module widget-parent

 */

var Lang = Y.Lang,

    RENDERED = "rendered",

    BOUNDING_BOX = "boundingBox";

/**

 * Widget extension providing functionality enabling a Widget to be a

 * parent of another Widget.

 *

 * <p>In addition to the set of attributes supported by WidgetParent, the constructor

 * configuration object can also contain a <code>children</code> which can be used

 * to add child widgets to the parent during construction. The <code>children</code>

 * property is an array of either child widget instances or child widget configuration

 * objects, and is sugar for the <a href="#method_add">add</a> method. See the

 * <a href="#method_add">add</a> for details on the structure of the child widget

 * configuration object.

 * @class WidgetParent

 * @constructor

 * @uses ArrayList

 * @param {Object} config User configuration object.

 */

function Parent(config) {

    /**

    * Fires when a Widget is add as a child.  The event object will have a

    * 'child' property that returns a reference to the child Widget, as well

    * as an 'index' property that returns a reference to the index specified

    * when the add() method was called.

    * <p>

    * Subscribers to the "on" moment of this event, will be notified

    * before a child is added.

    * </p>

    * <p>

    * Subscribers to the "after" moment of this event, will be notified

    * after a child is added.

    * </p>

    *

    * @event addChild

    * @preventable _defAddChildFn

    * @param {EventFacade} e The Event Facade

    */

    this.publish("addChild", {

        defaultTargetOnly: true,

        defaultFn: this._defAddChildFn

    });

    /**

    * Fires when a child Widget is removed.  The event object will have a

    * 'child' property that returns a reference to the child Widget, as well

    * as an 'index' property that returns a reference child's ordinal position.

    * <p>

    * Subscribers to the "on" moment of this event, will be notified

    * before a child is removed.

    * </p>

    * <p>

    * Subscribers to the "after" moment of this event, will be notified

    * after a child is removed.

    * </p>

    *

    * @event removeChild

    * @preventable _defRemoveChildFn

    * @param {EventFacade} e The Event Facade

    */

    this.publish("removeChild", {

        defaultTargetOnly: true,

        defaultFn: this._defRemoveChildFn

    });

    this._items = [];

    var children,

        handle;

    if (config && config.children) {

        children = config.children;

        handle = this.after("initializedChange", function (e) {

            this._add(children);

            handle.detach();

        });

    }

    //  Widget method overlap

    Y.after(this._renderChildren, this, "renderUI");

    Y.after(this._bindUIParent, this, "bindUI");

    this.after("selectionChange", this._afterSelectionChange);

    this.after("selectedChange", this._afterParentSelectedChange);

    this.after("activeDescendantChange", this._afterActiveDescendantChange);

    this._hDestroyChild = this.after("*:destroy", this._afterDestroyChild);

    this.after("*:focusedChange", this._updateActiveDescendant);

}

Parent.ATTRS = {

    /**

     * @attribute defaultChildType

     * @type {String|Object}

     *

     * @description String representing the default type of the children

     * managed by this Widget.  Can also supply default type as a constructor

     * reference.

     */

    defaultChildType: {

        setter: function (val) {

            var returnVal = Y.Attribute.INVALID_VALUE,

                FnConstructor = Lang.isString(val) ? Y[val] : val;

            if (Lang.isFunction(FnConstructor)) {

                returnVal = FnConstructor;

            }

            return returnVal;

        }

    },

    /**

     * @attribute activeDescendant

     * @type Widget

     * @readOnly

     *

     * @description Returns the Widget's currently focused descendant Widget.

     */

    activeDescendant: {

        readOnly: true

    },

    /**

     * @attribute multiple

     * @type Boolean

     * @default false

     * @writeOnce

     *

     * @description Boolean indicating if multiple children can be selected at

     * once.  Whether or not multiple selection is enabled is always delegated

     * to the value of the <code>multiple</code> attribute of the root widget

     * in the object hierarchy.

     */

    multiple: {

        value: false,

        validator: Lang.isBoolean,

        writeOnce: true,

        getter: function (value) {

            var root = this.get("root");

            return (root && root != this) ? root.get("multiple") : value;

        }

    },

    /**

     * @attribute selection

     * @type {ArrayList|Widget}

     * @readOnly

     *

     * @description Returns the currently selected child Widget.  If the

     * <code>mulitple</code> attribte is set to <code>true</code> will

     * return an Y.ArrayList instance containing the currently selected

     * children.  If no children are selected, will return null.

     */

    selection: {

        readOnly: true,

        setter: "_setSelection",

        getter: function (value) {

            var selection = Lang.isArray(value) ?

                    (new Y.ArrayList(value)) : value;

            return selection;

        }

    },

    selected: {

        setter: function (value) {

            //  Enforces selection behavior on for parent Widgets.  Parent's

            //  selected attribute can be set to the following:

            //  0 - Not selected

            //  1 - Fully selected (all children are selected).  In order for

            //  all children to be selected, multiple selection must be

            //  enabled.  Therefore, you cannot set the "selected" attribute

            //  on a parent Widget to 1 unless multiple selection is enabled.

            //  2 - Partially selected, meaning one ore more (but not all)

            //  children are selected.

            var returnVal = value;

            if (value === 1 && !this.get("multiple")) {

                Y.log('The selected attribute can only be set to 1 if the "multiple" attribute is set to true.', "error", "widget");

                returnVal = Y.Attribute.INVALID_VALUE;

            }

            return returnVal;

        }

    }

};

Parent.prototype = {

    /**

     * The destructor implementation for Parent widgets. Destroys all children.

     * @method destructor

     */

    destructor: function() {

        this._destroyChildren();

    },

    /**

     * Destroy event listener for each child Widget, responsible for removing

     * the destroyed child Widget from the parent's internal array of children

     * (_items property).

     *

     * @method _afterDestroyChild

     * @protected

     * @param {EventFacade} event The event facade for the attribute change.

     */

    _afterDestroyChild: function (event) {

        var child = event.target;

        if (child.get("parent") == this) {

            child.remove();

        }

    },

    /**

     * Attribute change listener for the <code>selection</code>

     * attribute, responsible for setting the value of the

     * parent's <code>selected</code> attribute.

     *

     * @method _afterSelectionChange

     * @protected

     * @param {EventFacade} event The event facade for the attribute change.

     */

    _afterSelectionChange: function (event) {

        if (event.target == this && event.src != this) {

            var selection = event.newVal,

                selectedVal = 0;    //  Not selected

            if (selection) {

                selectedVal = 2;    //  Assume partially selected, confirm otherwise

                if (Y.instanceOf(selection, Y.ArrayList) &&

                    (selection.size() === this.size())) {

                    selectedVal = 1;    //  Fully selected

                }

            }

            this.set("selected", selectedVal, { src: this });

        }

    },

    /**

     * Attribute change listener for the <code>activeDescendant</code>

     * attribute, responsible for setting the value of the

     * parent's <code>activeDescendant</code> attribute.

     *

     * @method _afterActiveDescendantChange

     * @protected

     * @param {EventFacade} event The event facade for the attribute change.

     */

    _afterActiveDescendantChange: function (event) {

        var parent = this.get("parent");

        if (parent) {

            parent._set("activeDescendant", event.newVal);

        }

    },

    /**

     * Attribute change listener for the <code>selected</code>

     * attribute, responsible for syncing the selected state of all children to

     * match that of their parent Widget.

     *

     *

     * @method _afterParentSelectedChange

     * @protected

     * @param {EventFacade} event The event facade for the attribute change.

     */

    _afterParentSelectedChange: function (event) {

        var value = event.newVal;

        if (this == event.target && event.src != this &&

            (value === 0 || value === 1)) {

            this.each(function (child) {

                //  Specify the source of this change as the parent so that

                //  value of the parent's "selection" attribute isn't

                //  recalculated

                child.set("selected", value, { src: this });

            }, this);

        }

    },

    /**

     * Default setter for <code>selection</code> attribute changes.

     *

     * @method _setSelection

     * @protected

     * @param child {Widget|Array} Widget or Array of Widget instances.

     * @return {Widget|Array} Widget or Array of Widget instances.

     */

    _setSelection: function (child) {

        var selection = null,

            selected;

        if (this.get("multiple") && !this.isEmpty()) {

            selected = [];

            this.each(function (v) {

               if (v.get("selected") > 0) {

                   selected.push(v);

               }

            });

            if (selected.length > 0) {

                selection = selected;

            }

        }

        else {

            if (child.get("selected") > 0) {

                selection = child;

            }

        }

        return selection;

    },

    /**

     * Attribute change listener for the <code>selected</code>

     * attribute of child Widgets, responsible for setting the value of the

     * parent's <code>selection</code> attribute.

     *

     * @method _updateSelection

     * @protected

     * @param {EventFacade} event The event facade for the attribute change.

     */

    _updateSelection: function (event) {

        var child = event.target,

            selection;

        if (child.get("parent") == this) {

            if (event.src != "_updateSelection") {

                selection = this.get("selection");

                if (!this.get("multiple") && selection && event.newVal > 0) {

                    //  Deselect the previously selected child.

                    //  Set src equal to the current context to prevent

                    //  unnecessary re-calculation of the selection.

                    selection.set("selected", 0, { src: "_updateSelection" });

                }

                this._set("selection", child);

            }

            if (event.src == this) {

                this._set("selection", child, { src: this });

            }

        }

    },

    /**

     * Attribute change listener for the <code>focused</code>

     * attribute of child Widgets, responsible for setting the value of the

     * parent's <code>activeDescendant</code> attribute.

     *

     * @method _updateActiveDescendant

     * @protected

     * @param {EventFacade} event The event facade for the attribute change.

     */

    _updateActiveDescendant: function (event) {

        var activeDescendant = (event.newVal === true) ? event.target : null;

        this._set("activeDescendant", activeDescendant);

    },

    /**

     * Creates an instance of a child Widget using the specified configuration.

     * By default Widget instances will be created of the type specified

     * by the <code>defaultChildType</code> attribute.  Types can be explicitly

     * defined via the <code>childType</code> property of the configuration object

     * literal. The use of the <code>type</code> property has been deprecated, but

     * will still be used as a fallback, if <code>childType</code> is not defined,

     * for backwards compatibility.

     *

     * @method _createChild

     * @protected

     * @param config {Object} Object literal representing the configuration

     * used to create an instance of a Widget.

     */

    _createChild: function (config) {

        var defaultType = this.get("defaultChildType"),

            altType = config.childType || config.type,

            child,

            Fn,

            FnConstructor;

        if (altType) {

            Fn = Lang.isString(altType) ? Y[altType] : altType;

        }

        if (Lang.isFunction(Fn)) {

            FnConstructor = Fn;

        } else if (defaultType) {

            // defaultType is normalized to a function in it's setter

            FnConstructor = defaultType;

        }

        if (FnConstructor) {

            child = new FnConstructor(config);

        } else {

            Y.error("Could not create a child instance because its constructor is either undefined or invalid.");

        }

        return child;

    },

    /**

     * Default addChild handler

     *

     * @method _defAddChildFn

     * @protected

     * @param event {EventFacade} The Event object

     * @param child {Widget} The Widget instance, or configuration

     * object for the Widget to be added as a child.

     * @param index {Number} Number representing the position at

     * which the child will be inserted.

     */

    _defAddChildFn: function (event) {

        var child = event.child,

            index = event.index,

            children = this._items;

        if (child.get("parent")) {

            child.remove();

        }

        if (Lang.isNumber(index)) {

            children.splice(index, 0, child);

        }

        else {

            children.push(child);

        }

        child._set("parent", this);

        child.addTarget(this);

        // Update index in case it got normalized after addition

        // (e.g. user passed in 10, and there are only 3 items, the actual index would be 3. We don't want to pass 10 around in the event facade).

        event.index = child.get("index");

        //  TO DO: Remove in favor of using event bubbling

        child.after("selectedChange", Y.bind(this._updateSelection, this));

    },

    /**

     * Default removeChild handler

     *

     * @method _defRemoveChildFn

     * @protected

     * @param event {EventFacade} The Event object

     * @param child {Widget} The Widget instance to be removed.

     * @param index {Number} Number representing the index of the Widget to

     * be removed.

     */

    _defRemoveChildFn: function (event) {

        var child = event.child,

            index = event.index,

            children = this._items;

        if (child.get("focused")) {

            child.blur(); // focused is readOnly, so use the public i/f to unset it

        }

        if (child.get("selected")) {

            child.set("selected", 0);

        }

        children.splice(index, 1);

        child.removeTarget(this);

        child._oldParent = child.get("parent");

        child._set("parent", null);

    },

    /**

    * @method _add

    * @protected

    * @param child {Widget|Object|Array} The Widget instance, or configuration

    * object for the Widget, or Array of Widget instances to be added as a child.

    * @param index {Number} Number representing the position at which the child

    * should be inserted.

    * @description Adds a Widget as a child.  If the specified Widget already

    * has a parent it will be removed from its current parent before

    * being added as a child.

    * @return {Widget|Array} Successfully added Widget or Array containing the

    * successfully added Widget instance(s). If no children where added, will

    * will return undefined.

    */

    _add: function (child, index) {

        var children,

            oChild,

            returnVal;

        if (Lang.isArray(child)) {

            children = [];

            Y.each(child, function (v, k) {

                oChild = this._add(v, (index + k));

                if (oChild) {

                    children.push(oChild);

                }

            }, this);

            if (children.length > 0) {

                returnVal = children;

            }

        }

        else {

            if (Y.instanceOf(child, Y.Widget)) {

                oChild = child;

            }

            else {

                oChild = this._createChild(child);

            }

            if (oChild && this.fire("addChild", { child: oChild, index: index })) {

                returnVal = oChild;

            }

        }

        return returnVal;

    },

    /**

    * @method add

    * @param child {Widget|Object|Array} The Widget instance, or configuration

    * object for the Widget, or Array of Widget instances to be added as a child.

    * The configuration object for the child can include a <code>childType</code>

    * property, which is either a constructor function or a string which names

    * a constructor function on the Y instance (e.g. "Tab" would refer to Y.Tab).

    * <code>childType</code> used to be named <code>type</code>, support for

    * which has been deprecated, but is still maintained for backward compatibility.

    * <code>childType</code> takes precedence over <code>type</code> if both are defined.

    * @param index {Number} Number representing the position at which the child

    * should be inserted.

    * @description Adds a Widget as a child.  If the specified Widget already

    * has a parent it will be removed from its current parent before

    * being added as a child.

    * @return {ArrayList} Y.ArrayList containing the successfully added

    * Widget instance(s).  If no children where added, will return an empty

    * Y.ArrayList instance.

    */

    add: function () {

        var added = this._add.apply(this, arguments),

            children = added ? (Lang.isArray(added) ? added : [added]) : [];

        return (new Y.ArrayList(children));

    },

    /**

    * @method remove

    * @param index {Number} (Optional.)  Number representing the index of the

    * child to be removed.

    * @description Removes the Widget from its parent.  Optionally, can remove

    * a child by specifying its index.

    * @return {Widget} Widget instance that was successfully removed, otherwise

    * undefined.

    */

    remove: function (index) {

        var child = this._items[index],

            returnVal;

        if (child && this.fire("removeChild", { child: child, index: index })) {

            returnVal = child;

        }

        return returnVal;

    },

    /**

    * @method removeAll

    * @description Removes all of the children from the Widget.

    * @return {ArrayList} Y.ArrayList instance containing Widgets that were

    * successfully removed.  If no children where removed, will return an empty

    * Y.ArrayList instance.

    */

    removeAll: function () {

        var removed = [],

            child;

        Y.each(this._items.concat(), function () {

            child = this.remove(0);

            if (child) {

                removed.push(child);

            }

        }, this);

        return (new Y.ArrayList(removed));

    },

    /**

     * Selects the child at the given index (zero-based).

     *

     * @method selectChild

     * @param {Number} i the index of the child to be selected

     */

    selectChild: function(i) {

        this.item(i).set('selected', 1);

    },

    /**

     * Selects all children.

     *

     * @method selectAll

     */

    selectAll: function () {

        this.set("selected", 1);

    },

    /**

     * Deselects all children.

     *

     * @method deselectAll

     */

    deselectAll: function () {

        this.set("selected", 0);

    },

    /**

     * Updates the UI in response to a child being added.

     *

     * @method _uiAddChild

     * @protected

     * @param child {Widget} The child Widget instance to render.

     * @param parentNode {Object} The Node under which the

     * child Widget is to be rendered.

     */

    _uiAddChild: function (child, parentNode) {

        child.render(parentNode);

        // TODO: Ideally this should be in Child's render UI.

        var childBB = child.get("boundingBox"),

            siblingBB,

            nextSibling = child.next(false),

            prevSibling;

        // Insert or Append to last child.

        // Avoiding index, and using the current sibling

        // state (which should be accurate), means we don't have

        // to worry about decorator elements which may be added

        // to the _childContainer node.

        if (nextSibling && nextSibling.get(RENDERED)) {

            siblingBB = nextSibling.get(BOUNDING_BOX);

            siblingBB.insert(childBB, "before");

        } else {

            prevSibling = child.previous(false);

            if (prevSibling && prevSibling.get(RENDERED)) {

                siblingBB = prevSibling.get(BOUNDING_BOX);

                siblingBB.insert(childBB, "after");

            } else if (!parentNode.contains(childBB)) {

                // Based on pull request from andreas-karlsson

                // https://github.com/yui/yui3/pull/25#issuecomment-2103536

                // Account for case where a child was rendered independently of the

                // parent-child framework, to a node outside of the parentNode,

                // and there are no siblings.

                parentNode.appendChild(childBB);

            }

        }

    },

    /**

     * Updates the UI in response to a child being removed.

     *

     * @method _uiRemoveChild

     * @protected

     * @param child {Widget} The child Widget instance to render.

     */

    _uiRemoveChild: function (child) {

        child.get("boundingBox").remove();

    },

    _afterAddChild: function (event) {

        var child = event.child;

        if (child.get("parent") == this) {

            this._uiAddChild(child, this._childrenContainer);

        }

    },

    _afterRemoveChild: function (event) {

        var child = event.child;

        if (child._oldParent == this) {

            this._uiRemoveChild(child);

        }

    },

    /**

     * Sets up DOM and CustomEvent listeners for the parent widget.

     * <p>

     * This method in invoked after bindUI is invoked for the Widget class

     * using YUI's aop infrastructure.

     * </p>

     *

     * @method _bindUIParent

     * @protected

     */

    _bindUIParent: function () {

        this.after("addChild", this._afterAddChild);

        this.after("removeChild", this._afterRemoveChild);

    },

    /**

     * Renders all child Widgets for the parent.

     * <p>

     * This method in invoked after renderUI is invoked for the Widget class

     * using YUI's aop infrastructure.

     * </p>

     * @method _renderChildren

     * @protected

     */

    _renderChildren: function () {

        /**

         * <p>By default WidgetParent will render it's children to the parent's content box.</p>

         *

         * <p>If the children need to be rendered somewhere else, the _childrenContainer property

         * can be set to the Node which the children should be rendered to. This property should be

         * set before the _renderChildren method is invoked, ideally in your renderUI method,

         * as soon as you create the element to be rendered to.</p>

         *

         * @protected

         * @property _childrenContainer

         * @value The content box

         * @type Node

         */

        var renderTo = this._childrenContainer || this.get("contentBox");

        this._childrenContainer = renderTo;

        this.each(function (child) {

            child.render(renderTo);

        });

    },

    /**

     * Destroys all child Widgets for the parent.

     * <p>

     * This method is invoked before the destructor is invoked for the Widget

     * class using YUI's aop infrastructure.

     * </p>

     * @method _destroyChildren

     * @protected

     */

    _destroyChildren: function () {

        //  Detach the handler responsible for removing children in

        //  response to destroying them since:

        //  1)  It is unnecessary/inefficient at this point since we are doing

        //      a batch destroy of all children.

        //  2)  Removing each child will affect our ability to iterate the

        //      children since the size of _items will be changing as we

        //      iterate.

        this._hDestroyChild.detach();

        //  Need to clone the _items array since

        this.each(function (child) {

            child.destroy();

        });

    }

};

Y.augment(Parent, Y.ArrayList);

Y.WidgetParent = Parent;

}, '3.18.1', {"requires": ["arraylist", "base-build", "widget"]});