#region License
/* 
 * Copyright (C) 1999-2022 John Källén.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; see the file COPYING.  If not, write to
 * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
 */
#endregion

using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Collections.Specialized;
using System.Linq;

namespace Reko.Core.Collections
{
    /// <summary> 
    /// Represents a dynamic data collection that provides notifications
    /// when items get added, removed, or when the whole list is refreshed. 
    /// </summary> 
    /// <typeparam name="T"></typeparam> 
    public class ObservableRangeCollection<T> : ObservableCollection<T>
    {
        /// <summary> 
        /// Adds the elements of the specified collection to the end of the ObservableCollection(Of T). 
        /// </summary> 
        public void AddRange(IEnumerable<T> collection)
        {
            if (collection == null) 
                throw new ArgumentNullException(nameof(collection));
            var items = collection.ToList();        // Avoid iterating the collection twice.
            foreach (var i in items)
            {
                Items.Add(i);
            }
            OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Add, items));
        }

        /// <summary> 
        /// Removes the first occurence of each item in the specified collection from ObservableCollection(Of T). 
        /// </summary> 
        public void RemoveRange(IEnumerable<T> collection)
        {
            if (collection is null)
                throw new ArgumentNullException(nameof(collection));
            foreach (var i in collection)
                Items.Remove(i);
            OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Remove, collection.ToList()));
        }

        /// <summary> 
        /// Clears the current collection and replaces it with the specified item. 
        /// </summary> 
        public void Replace(T item)
        {
            ReplaceRange(new T[] { item });
        }

        /// <summary> 
        /// Clears the current collection and replaces it with the specified collection. 
        /// </summary> 
        public void ReplaceRange(IEnumerable<T> collection)
        {
            if (collection is null) 
                throw new ArgumentNullException(nameof(collection));

            Items.Clear();
            foreach (var i in collection) 
                Items.Add(i);
            OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset));
        }

        /// <summary> 
        /// Initializes a new instance of the System.Collections.ObjectModel.ObservableCollection(Of T) class. 
        /// </summary> 
        public ObservableRangeCollection() : base() 
        { }

        /// <summary> 
        /// Initializes a new instance of the System.Collections.ObjectModel.ObservableCollection(Of T) class that contains elements copied from the specified collection. 
        /// </summary> 
        /// <param name="collection">collection: The collection from which the elements are copied.</param> 
        /// <exception cref="System.ArgumentNullException">The collection parameter cannot be null.</exception> 
        public ObservableRangeCollection(IEnumerable<T> collection): base(collection)
        { 
        }
    }
}