//******************************************************************************************************
//  SecurityGroups.cs - Gbtc
//
//  Copyright © 2012, Grid Protection Alliance.  All Rights Reserved.
//
//  Licensed to the Grid Protection Alliance (GPA) under one or more contributor license agreements. See
//  the NOTICE file distributed with this work for additional information regarding copyright ownership.
//  The GPA licenses this file to you under the MIT License (MIT), the "License"; you may
//  not use this file except in compliance with the License. You may obtain a copy of the License at:
//
//      http://www.opensource.org/licenses/MIT
//
//  Unless agreed to in writing, the subject software distributed under the License is distributed on an
//  "AS-IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. Refer to the
//  License for the specific language governing permissions and limitations.
//
//  Code Modification History:
//  ----------------------------------------------------------------------------------------------------
//  05/10/2011 - Mehulbhai P Thakkar
//       Generated original version of source code.
//  12/20/2012 - Starlynn Danyelle Gilliam
//       Modified Header.
//
//******************************************************************************************************

using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Windows;
using System.Windows.Input;
using GSF.TimeSeries.UI.Commands;
using GSF.TimeSeries.UI.DataModels;

namespace GSF.TimeSeries.UI.ViewModels
{
    /// <summary>
    /// Class to hold bindable <see cref="SecurityGroup"/> collection.
    /// </summary>
    internal class SecurityGroups : PagedViewModelBase<SecurityGroup, Guid>
    {
        #region [ Members ]

        // Fields
        private RelayCommand m_addUserCommand;
        private RelayCommand m_removeUserCommand;

        #endregion

        #region [ Properties ]

        /// <summary>
        /// Gets flag that determines if <see cref="PagedViewModelBase{T1, T2}.CurrentItem"/> is a new record.
        /// </summary>
        public override bool IsNewRecord
        {
            get
            {
                return (CurrentItem.ID == null || CurrentItem.ID == Guid.Empty);
            }
        }

        /// <summary>
        /// Gets <see cref="ICommand"/> for add users to group operation.
        /// </summary>
        public ICommand AddUserCommand
        {
            get
            {
                if (m_addUserCommand == null)
                    m_addUserCommand = new RelayCommand(AddUser, (param) => CanSave);

                return m_addUserCommand;
            }
        }

        /// <summary>
        /// Gets <see cref="ICommand"/> to remove users from group operation.
        /// </summary>
        public ICommand RemoveUserCommand
        {
            get
            {
                if (m_removeUserCommand == null)
                    m_removeUserCommand = new RelayCommand(RemoveUser, (param) => CanSave);

                return m_removeUserCommand;
            }
        }

        #endregion

        #region [ Constructor ]

        /// <summary>
        /// Creates an instance of <see cref="SecurityGroups"/> class.
        /// </summary>
        /// <param name="itemsPerPage">Integer value to determine number of items per page.</param>
        /// <param name="autoSave">Boolean value to determine is user changes should be saved automatically.</param>
        public SecurityGroups(int itemsPerPage, bool autoSave = true)
            : base(itemsPerPage, autoSave)
        {
        }

        #endregion

        #region [ Methods ]

        /// <summary>
        /// Gets the primary key value of the <see cref="PagedViewModelBase{T1, T2}.CurrentItem"/>.
        /// </summary>
        /// <returns>The primary key value of the <see cref="PagedViewModelBase{T1, T2}.CurrentItem"/>.</returns>
        public override Guid GetCurrentItemKey()
        {
            return CurrentItem.ID;
        }

        /// <summary>
        /// Gets the string based named identifier of the <see cref="PagedViewModelBase{T1, T2}.CurrentItem"/>.
        /// </summary>
        /// <returns>The string based named identifier of the <see cref="PagedViewModelBase{T1, T2}.CurrentItem"/>.</returns>
        public override string GetCurrentItemName()
        {
            return CurrentItem.Name;
        }

        /// <summary>
        /// Creates a new instance of <see cref="SecurityGroup"/> and assigns it to CurrentItem.
        /// </summary>
        public override void Clear()
        {
            base.Clear();
            CurrentItem = ItemsSource[0];
        }

        /// <summary>
        /// Handles <see cref="AddUserCommand"/>.
        /// </summary>
        /// <param name="parameter">Collection of users to be added to <see cref="SecurityGroup"/>.</param>
        private void AddUser(object parameter)
        {
            ObservableCollection<object> usersToBeAdded = (ObservableCollection<object>)parameter;

            if (usersToBeAdded.Count > 0)
            {
                List<Guid> userIDs = new List<Guid>();

                foreach (object item in usersToBeAdded)
                    userIDs.Add(((KeyValuePair<Guid, string>)item).Key);

                string result = SecurityGroup.AddUsers(null, CurrentItem.ID, userIDs);

                Popup(result, "Add Group Users", MessageBoxImage.Information);

                CurrentItem.CurrentUsers = SecurityGroup.GetCurrentUsers(null, CurrentItem.ID);
                CurrentItem.PossibleUsers = SecurityGroup.GetPossibleUsers(null, CurrentItem.ID);
            }
        }

        /// <summary>
        /// Handles <see cref="RemoveUserCommand"/>.
        /// </summary>
        /// <param name="parameter">Collection of users to be removed from <see cref="SecurityGroup"/>.</param>
        private void RemoveUser(object parameter)
        {
            ObservableCollection<object> usersToBeRemoved = (ObservableCollection<object>)parameter;

            if (usersToBeRemoved.Count > 0)
            {
                List<Guid> userIDs = new List<Guid>();

                foreach (object item in usersToBeRemoved)
                    userIDs.Add(((KeyValuePair<Guid, string>)item).Key);

                string result = SecurityGroup.RemoveUsers(null, CurrentItem.ID, userIDs);

                Popup(result, "Remove Group Users", MessageBoxImage.Information);

                CurrentItem.CurrentUsers = SecurityGroup.GetCurrentUsers(null, CurrentItem.ID);
                CurrentItem.PossibleUsers = SecurityGroup.GetPossibleUsers(null, CurrentItem.ID);
            }
        }

        #endregion
    }
}