//-----------------------------------------------------------------------
// <copyright file="RSSChannelModel.cs" company="BTU/IIT">
// The MIT License (MIT). Copyright (c) 2013 BTU/IIT.
// </copyright>
// <author>fiedlchr</author>
// <date>15.10.2013</date>
// <summary>Implements the RSS channel model class</summary>
//-----------------------------------------------------------------------
namespace CampusAppWPortalLib8.Model.RSS
{
    using System.Collections.ObjectModel;
    using System.Collections.Specialized;
    using System.Linq;
    using System.Xml.Serialization;

    /// <summary> Channel Model, which contains the RSS feed item list. </summary>
    /// <remarks> fiedlchr, 15.10.2013. </remarks>
    public class RSSChannelModel
    {
        /// <summary> RSS feed information item list. </summary>
        private ObservableCollection<RSSModel> item;

        #region Constructor

        /// <summary> Initializes a new instance of the <see cref="RSSChannelModel" /> class. </summary>
        /// <remarks> fiedlchr, 15.10.2013. </remarks>
        public RSSChannelModel()
        {
            this.item = new ObservableCollection<RSSModel>();
            this.item.CollectionChanged += new NotifyCollectionChangedEventHandler(this.OnListChanged);
        }

        #endregion

        #region Property

        /// <summary> Gets or sets the RSS feed item list. </summary>
        /// <value> The item. </value>
        [XmlElement("item")]
        public ObservableCollection<RSSModel> Item
        {
            get
            {
                return this.item;
            }

            set
            {
                if (value != this.item)
                {
                    this.item = value;
                }
            }
        }

        #endregion

        #region Method

        /// <summary> Order by date. </summary>
        /// <remarks> fiedlchr, 15.10.2013. </remarks>
        /// <param name="asc"> (Optional) the ascending. </param>
        public void OrderByDate(bool asc = false)
        {
            this.item.CollectionChanged -= this.OnListChanged;

            if (asc == false)
            {
                var sortedOC = from elem in this.item
                               orderby elem.DTTimestamp descending
                               select elem;

                this.item = new ObservableCollection<RSSModel>(sortedOC);
                this.FixIndex();
                this.item.CollectionChanged += new NotifyCollectionChangedEventHandler(this.OnListChanged);
            }
            else
            {
                var sortedOC = from elem in this.item
                               orderby elem.DTTimestamp ascending
                               select elem;

                this.item = new ObservableCollection<RSSModel>(sortedOC);
                this.FixIndex();
                this.item.CollectionChanged += new NotifyCollectionChangedEventHandler(this.OnListChanged);
            }
        }

        /// <summary>
        ///     Is called when the item list has changed. Here used for the add event. Set the index of
        ///     the last list element.
        /// </summary>
        /// <remarks> fiedlchr, 15.10.2013. </remarks>
        /// <param name="sender"> item list. </param>
        /// <param name="e">      event args. </param>
        private void OnListChanged(object sender, NotifyCollectionChangedEventArgs e)
        {
            if (e.Action == NotifyCollectionChangedAction.Add)
            {
                ObservableCollection<RSSModel> list = sender as ObservableCollection<RSSModel>;

                list[list.Count - 1].Index = list.Count - 1;
            }
        }

        /// <summary>Fixes the index property of the items.</summary>
        /// <remarks>Fiedler, 15.10.2013.</remarks>
        private void FixIndex()
        {
            for (int i = 0; i < this.item.Count(); i++)
            {
                this.item[i].Index = i;
            }
        }

        #endregion
    }
}