using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;

using Microsoft.Xna.Framework;

// ************************************************************************* //
// Disable 'missing xml comment' warning for this file since it has been
// generated by .NET Reflector and I'm not going to comment this all
// just so I have to start from scratch again when XNA gets updated
#pragma warning disable 1591
// ************************************************************************* //

namespace Nuclex
{
    /// <summary>A collection of game components.</summary>
    public sealed class GameComponentCollection : Collection<IGameComponent>
    {
        /// <summary>Raised when a component is added to the GameComponentCollection.</summary>
        public event EventHandler<GameComponentCollectionEventArgs> ComponentAdded;

        /// <summary>
        /// Raised when a component is removed from the GameComponentCollection.
        /// </summary>
        public event EventHandler<GameComponentCollectionEventArgs> ComponentRemoved;

        // Methods
        internal GameComponentCollection()
        {
        }

        /// <summary>Removes all children from the collection. </summary>
        protected override void ClearItems()
        {
            for (int i = 0; i < base.Count; i++)
            {
                this.OnComponentRemoved(new GameComponentCollectionEventArgs(base[i]));
            }
            base.ClearItems();
        }

        /// <summary>Inserts a child object into the collection at the specified location. </summary>
        /// <param name="index">The position in the collection.</param>
        /// <param name="item">The child object being inserted.</param>
        protected override void InsertItem(int index, IGameComponent item)
        {
            if (base.IndexOf(item) != -1)
            {
                throw new ArgumentException("Resources.CannotAddSameComponentMultipleTimes");
            }
            base.InsertItem(index, item);
            if (item != null)
            {
                this.OnComponentAdded(new GameComponentCollectionEventArgs(item));
            }
        }

        private void OnComponentAdded(GameComponentCollectionEventArgs eventArgs)
        {
            if (this.ComponentAdded != null)
            {
                this.ComponentAdded(this, eventArgs);
            }
        }

        private void OnComponentRemoved(GameComponentCollectionEventArgs eventArgs)
        {
            if (this.ComponentRemoved != null)
            {
                this.ComponentRemoved(this, eventArgs);
            }
        }

        /// <summary>Removes a child object in the collection. </summary>
        /// <param name="index">The index of the item being removed.</param>
        protected override void RemoveItem(int index)
        {
            IGameComponent gameComponent = base[index];
            base.RemoveItem(index);
            if (gameComponent != null)
            {
                this.OnComponentRemoved(new GameComponentCollectionEventArgs(gameComponent));
            }
        }

        /// <summary>Modifies the specified child object in the collection. </summary>
        /// <param name="index">The position in the collection.</param>
        /// <param name="item">The child object being modified.</param>
        protected override void SetItem(int index, IGameComponent item)
        {
            throw new NotSupportedException("Resources.CannotSetItemsIntoGameComponentCollection");
        }
    }
} // namespace Nuclex