﻿/* ------------------------------------------------------------------------- */
//
// Copyright (c) 2010 CubeSoft, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//  http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
/* ------------------------------------------------------------------------- */
using System.Linq;
using System.Windows.Controls;
using Microsoft.Xaml.Behaviors;

namespace Cube.Xui.Behaviors
{
    /* --------------------------------------------------------------------- */
    ///
    /// SelectionBehavior
    ///
    /// <summary>
    /// Provides functionality to bind a ViewModel to either the
    /// ListBoxItem or the ListViewItem.
    /// </summary>
    ///
    /* --------------------------------------------------------------------- */
    public class SelectionBehavior : Behavior<ListBox>
    {
        #region Methods

        /* ----------------------------------------------------------------- */
        ///
        /// OnAttached
        ///
        /// <summary>
        /// Called after the action is attached to an AssociatedObject.
        /// </summary>
        ///
        /* ----------------------------------------------------------------- */
        protected override void OnAttached()
        {
            base.OnAttached();
            AssociatedObject.SelectionChanged -= WhenSelectionChanged;
            AssociatedObject.SelectionChanged += WhenSelectionChanged;
        }

        /* ----------------------------------------------------------------- */
        ///
        /// OnDetaching
        ///
        /// <summary>
        /// Called when the action is being detached from its
        /// AssociatedObject, but before it has actually occurred.
        /// </summary>
        ///
        /* ----------------------------------------------------------------- */
        protected override void OnDetaching()
        {
            AssociatedObject.SelectionChanged -= WhenSelectionChanged;
            base.OnDetaching();
        }

        #endregion

        #region Implementations

        /* ----------------------------------------------------------------- */
        ///
        /// WhenSelectionChanged
        ///
        /// <summary>
        /// Called after the selected items of the AssociatedObject is
        /// changed.
        /// </summary>
        ///
        /* ----------------------------------------------------------------- */
        private void WhenSelectionChanged(object s, SelectionChangedEventArgs e)
        {
            foreach (var ri in e.RemovedItems.OfType<IListItem>()) ri.Selected = false;
            foreach (var ai in e.AddedItems.OfType<IListItem>()) ai.Selected = true;
        }

        #endregion
    }
}
