// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
 
//
// Description: ParameterCollection with a simple change notification callback
//              and can be made Read-Only.  Created for ObjectDataProvider.
//
 
using System.Collections;   // IList
using System.Collections.ObjectModel;   // Collection<T>
using System.Windows;   // SR
 
namespace MS.Internal.Data
{
    internal class ParameterCollection : Collection<object>, IList
    {
        //------------------------------------------------------
        //
        //  Constructors
        //
        //------------------------------------------------------
 
        #region Constructors
 
        public ParameterCollection(ParameterCollectionChanged parametersChanged)
            : base()
        {
            _parametersChanged = parametersChanged;
        }
 
        #endregion Constructors
 
        //------------------------------------------------------
        //
        //  Interface Properties
        //
        //------------------------------------------------------
 
        #region Interface Properties
 
        bool IList.IsReadOnly
        {
            get
            {
                return this.IsReadOnly;
            }
        }
 
        bool IList.IsFixedSize
        {
            get
            {
                return this.IsFixedSize;
            }
        }
 
        #endregion Interface Properties
 
        //------------------------------------------------------
        //
        //  Protected Methods
        //
        //------------------------------------------------------
 
        #region Protected Methods
 
        // Methods
 
        protected override void ClearItems()
        {
            CheckReadOnly();
            base.ClearItems();
            OnCollectionChanged();
        }
 
        protected override void InsertItem(int index, object value)
        {
            CheckReadOnly();
            base.InsertItem(index, value);
            OnCollectionChanged();
        }
 
        protected override void RemoveItem(int index)
        {
            CheckReadOnly();
            base.RemoveItem(index);
            OnCollectionChanged();
        }
 
        protected override void SetItem(int index, object value)
        {
            CheckReadOnly();
            base.SetItem(index, value);
            OnCollectionChanged();
        }
 
        #endregion Protected Methods
 
        //------------------------------------------------------
        //
        //  Protected Properties
        //
        //------------------------------------------------------
 
        #region Protected Properties
 
        protected virtual bool IsReadOnly
        {
            get
            {
                return _isReadOnly;
            }
            set
            {
                _isReadOnly = value;
            }
        }
 
        protected bool IsFixedSize
        {
            get
            {
                return this.IsReadOnly;
            }
        }
 
        #endregion Protected Properties
 
        //------------------------------------------------------
        //
        //  Internal Methods
        //
        //------------------------------------------------------
 
        #region Internal Methods
 
        /// <summary>
        /// sets whether the collection is read-only
        /// </summary>
        internal void SetReadOnly(bool isReadOnly)
        {
            this.IsReadOnly = isReadOnly;
        }
 
        /// <summary>
        /// silently clear the list.
        /// </summary>
        /// <remarks>
        /// this internal method is not affected by the state of IsReadOnly.
        /// </remarks>
        internal void ClearInternal()
        {
            base.ClearItems();
        }
 
        #endregion Internal Methods
 
        //------------------------------------------------------
        //
        //  Private Methods
        //
        //------------------------------------------------------
 
        #region Private Methods
 
        private void CheckReadOnly()
        {
            if (this.IsReadOnly)
            {
                throw new InvalidOperationException(SR.ObjectDataProviderParameterCollectionIsNotInUse);
            }
        }
 
        /// <summary>
        /// notify ObjectDataProvider that the parameters have changed
        /// </summary>
        private void OnCollectionChanged()
        {
            _parametersChanged(this);
        }
 
        #endregion Private Methods
 
        //------------------------------------------------------
        //
        //  Private Fields
        //
        //------------------------------------------------------
 
        #region Private Fields
 
        private bool _isReadOnly = false;
        private ParameterCollectionChanged _parametersChanged;
 
        #endregion Private Fields
    }
 
    internal delegate void ParameterCollectionChanged(ParameterCollection parameters);
}