/*
 * UpdateNotifyingList.cs
 * 
 * Copyright © 2009
 * Diversified Technical Systems, Inc.
 * All Rights Reserved
 */

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using DTS.Common.Utilities.DotNetProgrammingConstructs;

namespace DTS.Common.Utilities
{
    public class UpdateNotifyingList<T> : Exceptional
    {
        /// <summary>
        /// Initialize an instance of the UpdateNotifyingList class.
        /// </summary>
        public UpdateNotifyingList()
        {
        }

        /// <summary>
        /// Get/set the notification-bound items in this list.
        /// </summary>
        public List<T> Items
        {
            get => _Items.Value;
            set
            {
                try
                {   //
                    // Update list items and then notify all subscribers.
                    //
                    _Items.Value = value;
                    OnUpdate(value);
                }
                catch (System.Exception ex)
                {
                    throw new UpdateNotifyingList<T>.Exception("encountered problem setting UpdateNotifyingList.Items", ex);
                }
            }
        }
        private Property<List<T>> _Items
            = new Property<List<T>>("NotifyingList", null, false);

        /// <summary>
        /// Callback method to be invoked whenever the notifying list is updated.
        /// </summary>
        /// 
        /// <param name="updatedContents">
        /// The updated contents of the notifying list.
        /// </param>
        /// 
        public delegate void OnUpdateCallback(List<T> updatedContents);

        /// <summary>
        /// Subscribers to be notified whenever this list is changed.
        /// </summary>
        public event OnUpdateCallback OnUpdate;
    }
}