using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Input;
using System.Windows.Interop;
using System.Windows.Media.Imaging;
using Hik.Samples.Scs.IrcChat.Arguments;
using Hik.Samples.Scs.IrcChat.Client;
using Hik.Samples.Scs.IrcChat.Controls;
using Microsoft.Win32;

namespace Hik.Samples.Scs.IrcChat.Windows
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window, IChatRoomView, ILoginFormView, IMessagingAreaContainer
    {
        #region ILoginFormView implementation

        /// <summary>
        /// IP address of server to be connected.
        /// </summary>
        public string ServerIpAddress
        {
            get
            {
                return (string)Dispatcher.Invoke(new Func<string>(() => txtServerIpAddress.Text));
            }
        }

        /// <summary>
        /// TCP Port number of server to be connected.
        /// </summary>
        public int ServerTcpPort
        {
            get
            {
                return (int)Dispatcher.Invoke(new Func<int>(() => Convert.ToInt32(txtServerPort.Text)));
            }
        }

        /// <summary>
        /// User Login informations to be used while logging on to the server.
        /// </summary>
        public UserInfo CurrentUserInfo
        {
            get
            {
                return (UserInfo)Dispatcher.Invoke(
                    new Func<UserInfo>(() => new UserInfo
                                             {
                                                 Nick = txtNick.Text,
                                                 Status = UserStatus.Available,
                                                 AvatarBytes = GetBytesOfCurrentUserAvatar()
                                             }));
            }
        }

        #endregion

        #region IChatRoomView implementation

        /// <summary>
        /// This method is called when a message is sent to chat room.
        /// </summary>
        /// <param name="nick">Nick of sender</param>
        /// <param name="message">Message</param>
        public void OnMessageReceived(string nick, ChatMessage message)
        {
            Dispatcher.Invoke(new Action(() => messagingArea.MessageReceived(nick, message)));
        }

        /// <summary>
        /// This method is called when a private message is sent to the current user.
        /// </summary>
        /// <param name="nick">Nick of sender</param>
        /// <param name="message">The message</param>
        public void OnPrivateMessageReceived(string nick, ChatMessage message)
        {
            Dispatcher.Invoke(new Action(() => OnPrivateMessageReceivedInternal(nick, message)));
        }

        /// <summary>
        /// This method is called when user successfully logged in to chat server.
        /// </summary>
        public void OnLoggedIn()
        {
            Dispatcher.Invoke(new Action(OnLoggedInInternal));
        }

        /// <summary>
        /// This method is used to inform view if login is failed.
        /// </summary>
        /// <param name="errorMessage">Detail of error</param>
        public void OnLoginError(string errorMessage)
        {
            MessageBox.Show(errorMessage, "Login Error!", MessageBoxButton.OK, MessageBoxImage.Error);
        }

        /// <summary>
        /// This method is called when connection to server is closed.
        /// </summary>
        public void OnLoggedOut()
        {
            Dispatcher.Invoke(new Action(OnLoggedOutInternal));
        }

        /// <summary>
        /// This methos is used to add a new user to user list in room view.
        /// </summary>
        /// <param name="userInfo">Informations of new user</param>
        public void AddUserToList(UserInfo userInfo)
        {
            Dispatcher.Invoke(new Action(() => AddUserToListInternal(userInfo)));
        }

        /// <summary>
        /// This metrhod is used to remove a user (that is disconnected from server) from user list in room view.
        /// </summary>
        /// <param name="nick">Nick of user to remove</param>
        public void RemoveUserFromList(string nick)
        {
            Dispatcher.Invoke(new Action(() => RemoveUserFromListInternal(nick)));
        }

        /// <summary>
        /// This method is called from chat server to inform that a user changed his/her status.
        /// </summary>
        /// <param name="nick">Nick of the user</param>
        /// <param name="newStatus">New status of the user</param>
        public void OnUserStatusChange(string nick, UserStatus newStatus)
        {
            Dispatcher.Invoke(new Action(() => OnUserStatusChangeInternal(nick, newStatus)));
        }

        #endregion

        #region IMessagingAreaContainer implementation

        /// <summary>
        /// Sends a message to the room.
        /// </summary>
        public void SendMessage(ChatMessage message)
        {
            _controller.SendMessageToRoom(message);
        }

        #endregion

        #region Private fields

        /// <summary>
        /// Reference to the controller object.
        /// </summary>
        private readonly IChatController _controller;

        /// <summary>
        /// List of open private chat windows.
        /// </summary>
        private readonly SortedList<string, PrivateChatWindow> _privateChatWindows;

        /// <summary>
        /// Reference to the user preferences.
        /// </summary>
        private readonly UserPreferences _userPreferences;

        #endregion

        #region Constructor and Initialize methods

        /// <summary>
        /// Creates a new form with a reference to the controller object.
        /// </summary>
        /// <param name="controller">Reference to the controller object</param>
        public MainWindow(IChatController controller)
        {
            _controller = controller;
            _privateChatWindows = new SortedList<string, PrivateChatWindow>();
            _userPreferences = UserPreferences.Current;

            InitializeComponent();
            InitializeControls();
        }

        /// <summary>
        /// Initializes some controls.
        /// </summary>
        private void InitializeControls()
        {
            messagingArea.MessagingAreaContainer = this;
            txtNick.Text = _userPreferences.Nick;
            txtServerIpAddress.Text = _userPreferences.ServerIpAddress;
            txtServerPort.Text = _userPreferences.ServerTcpPort.ToString();
            InitializeUserAvatar();
        }

        /// <summary>
        /// Initializes and shows user avatar.
        /// </summary>
        private void InitializeUserAvatar()
        {
            try
            {
                ChangeCurrentUserAvatar(_userPreferences.AvatarFile);
            }
            catch (Exception ex)
            {
                MessageBox.Show("Can not load avatar image. Error Detail: " + ex.Message, "Error!", MessageBoxButton.OK, MessageBoxImage.Error);
            }
        }

        #endregion

        #region Handlers for events of window and controls

        /// <summary>
        /// Handles Loaded event of this Window.
        /// </summary>
        /// <param name="sender">Source of event</param>
        /// <param name="e">Event arguments</param>
        private void Window_Loaded(object sender, RoutedEventArgs e)
        {
            txtNick.Focus();
            txtNick.SelectAll();
        }

        /// <summary>
        /// Hansles Closing event of this window.
        /// </summary>
        /// <param name="sender">Source of event</param>
        /// <param name="e">Event arguments</param>
        private void Window_Closing(object sender, System.ComponentModel.CancelEventArgs e)
        {
            _userPreferences.Save();
            _controller.Disconnect();
        }

        /// <summary>
        /// Handles TextChanged event of txtNick (on login screen). 
        /// </summary>
        /// <param name="sender">Source of event</param>
        /// <param name="e">Event arguments</param>
        private void txtNick_TextChanged(object sender, TextChangedEventArgs e)
        {
            lblCurrentUserNick.Content = txtNick.Text;
        }

        /// <summary>
        /// Handles Click event of 'Change to female' right menu item of avatar menu.
        /// Changes login avatar to default female avatar.
        /// </summary>
        /// <param name="sender">Source of event</param>
        /// <param name="e">Event arguments</param>
        private void ChangeToFemale_Click(object sender, RoutedEventArgs e)
        {
            try
            {
                ChangeCurrentUserAvatar(Path.Combine(ClientHelper.GetCurrentDirectory(), @"Images\user_female.png"));
            }
            catch (Exception ex)
            {
                MessageBox.Show("Can not load avatar image. Error Detail: " + ex.Message, "Error!", MessageBoxButton.OK, MessageBoxImage.Error);
            }
        }

        /// <summary>
        /// Handles Click event of 'Change to male' right menu item of avatar menu.
        /// Changes login avatar to default male avatar.
        /// </summary>
        /// <param name="sender">Source of event</param>
        /// <param name="e">Event arguments</param>
        private void ChangeToMale_Click(object sender, RoutedEventArgs e)
        {
            try
            {
                ChangeCurrentUserAvatar(Path.Combine(ClientHelper.GetCurrentDirectory(), @"Images\user_male.png"));
            }
            catch (Exception ex)
            {
                MessageBox.Show("Can not load avatar image. Error Detail: " + ex.Message, "Error!", MessageBoxButton.OK, MessageBoxImage.Error);
            }
        }

        /// <summary>
        /// Handles Click event of 'Select a picture...' menu item.
        /// </summary>
        /// <param name="sender">Source of event</param>
        /// <param name="e">Event arguments</param>
        private void SelectAvatar_Click(object sender, RoutedEventArgs e)
        {
            try
            {
                var avatarSelectDialog = new OpenFileDialog();
                avatarSelectDialog.Filter = "JPG Files|*.jpg|JPEG Files|*.jpeg|GIF Files|*.gif|PNG files|*.png|BMP Files|*.bmp";
                if (avatarSelectDialog.ShowDialog() == true)
                {
                    var selectedFile = avatarSelectDialog.FileName;
                    if (ClientHelper.GetFileSize(selectedFile) > (100 * 1024))
                    {
                        MessageBox.Show("You can not select avatar file larger than 100 KB.", "Warning!", MessageBoxButton.OK, MessageBoxImage.Warning);
                        return;
                    }

                    ChangeCurrentUserAvatar(selectedFile);
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show("Can not load avatar image. Error Detail: " + ex.Message, "Error!", MessageBoxButton.OK, MessageBoxImage.Error);
            }
        }

        /// <summary>
        /// Handles Client event of Login button.
        /// </summary>
        /// <param name="sender">Source of event</param>
        /// <param name="e">Event arguments</param>
        private void btnLogin_Click(object sender, RoutedEventArgs e)
        {
            ConnectToServer();
        }

        /// <summary>
        /// Handles KeyDown of Login form (actually the Border named brdConnect that contains login controls) 
        /// </summary>
        /// <param name="sender">Source of event</param>
        /// <param name="e">Event arguments</param>
        private void LoginForm_KeyDown(object sender, KeyEventArgs e)
        {
            //If user pressed to enter in login form, connect to server
            if (e.Key == Key.Enter)
            {
                ConnectToServer();
            }
        }

        /// <summary>
        /// Handles SelectionChanged event of user status combobox
        /// </summary>
        /// <param name="sender">Source of event</param>
        /// <param name="e">Event arguments</param>
        private void cmbCurrentUserStatus_SelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            if (!IsInitialized || cmbCurrentUserStatus.SelectedIndex < 0 || _controller == null)
            {
                return;
            }

            try
            {
                var newStatus = GetCurrentUserStatus();
                
                _controller.ChangeStatus(newStatus);

                //Change user's status on all open private chat windows
                foreach (var chatWindow in _privateChatWindows.Values.ToList())
                {
                    chatWindow.CurrentUserStatus = newStatus;
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show("Can not changes status. Error Detail: " + ex.Message, "Error!", MessageBoxButton.OK, MessageBoxImage.Error);
            }
        }

        /// <summary>
        /// Handles MouseDoubleClick event of all User cards.
        /// </summary>
        /// <param name="sender">Source of event</param>
        /// <param name="e">Event arguments</param>
        private void UserCard_MouseDoubleClick(object sender, MouseButtonEventArgs e)
        {
            if (e.ChangedButton != MouseButton.Left)
            {
                return;
            }

            var userCard = e.Source as UserCardControl;
            if (userCard == null)
            {
                return;
            }

            if (_privateChatWindows.ContainsKey(userCard.UserNick))
            {
                _privateChatWindows[userCard.UserNick].Activate();
            }
            else
            {
                _privateChatWindows[userCard.UserNick] = CreatePrivateChatWindow(userCard);
            }
        }

        /// <summary>
        /// Handles Closed event of Private chat windows.
        /// </summary>
        /// <param name="sender">Source of event</param>
        /// <param name="e">Event arguments</param>
        private void PrivateChatWindow_Closed(object sender, EventArgs e)
        {
            var privateChatWindow = sender as PrivateChatWindow;
            if (privateChatWindow == null)
            {
                return;
            }

            if (_privateChatWindows.ContainsKey(privateChatWindow.RemoteUserNick))
            {
                _privateChatWindows.Remove(privateChatWindow.RemoteUserNick);
            }
        }

        #endregion

        #region Private methods

        /// <summary>
        /// Connects to the server.
        /// This method is called on login.
        /// </summary>
        private void ConnectToServer()
        {
            if(string.IsNullOrEmpty(txtNick.Text))
            {
                MessageBox.Show("You must enter a nick to login to server.", "Warning!", MessageBoxButton.OK, MessageBoxImage.Warning);
                return;
            }

            if (string.IsNullOrEmpty(txtServerIpAddress.Text))
            {
                MessageBox.Show("You must enter IP address to connect to server.", "Warning!", MessageBoxButton.OK, MessageBoxImage.Warning);
                return;
            }
            
            if (string.IsNullOrEmpty(txtServerPort.Text))
            {
                MessageBox.Show("You must enter TCP port to connect to server.", "Warning!", MessageBoxButton.OK, MessageBoxImage.Warning);
                return;
            }

            try
            {
                _controller.Connect();
                _userPreferences.Nick = txtNick.Text;
                _userPreferences.ServerIpAddress = txtServerIpAddress.Text;
                try { _userPreferences.ServerTcpPort = Convert.ToInt32(txtServerPort.Text); } catch { }
                _userPreferences.Save();
            }
            catch (Exception ex)
            {
                MessageBox.Show("Can not connected to the server. Check Server IP and port. Error Detail: " + ex.Message, "Error!", MessageBoxButton.OK, MessageBoxImage.Error);
            }
        }

        /// <summary>
        /// This method is used to hide Login form when user succussfully logged into server.
        /// </summary>
        private void OnLoggedInInternal()
        {
            grdConnect.Visibility = Visibility.Collapsed;
            brdConnect.Visibility = Visibility.Collapsed;
        }

        /// <summary>
        /// This method is used to show Login form when connection to server is broken/closed.
        /// </summary>
        private void OnLoggedOutInternal()
        {
            foreach (var privateChatWindow in _privateChatWindows.Values.ToList())
            {
                privateChatWindow.Close();
            }

            spUsers.Children.Clear();
            grdConnect.Visibility = Visibility.Visible;
            brdConnect.Visibility = Visibility.Visible;
        }

        /// <summary>
        /// This method is used to send private message to proper private messaging window.
        /// </summary>
        /// <param name="nick">Nick of sender</param>
        /// <param name="message">Message</param>
        private void OnPrivateMessageReceivedInternal(string nick, ChatMessage message)
        {
            var userCard = FindUserInList(nick);
            if (userCard == null)
            {
                return;
            }

            if (!_privateChatWindows.ContainsKey(nick))
            {
                //Create new private chat window
                _privateChatWindows[nick] = CreatePrivateChatWindow(userCard);

                //Set initial state as minimized
                _privateChatWindows[nick].WindowState = WindowState.Minimized;
                
                //Flash the window button on taskbar to inform user
                WindowsHelper.FlashWindow(new WindowInteropHelper(_privateChatWindows[nick]).Handle, WindowsHelper.FlashWindowFlags.FLASHW_ALL, 2, 1000);
            }

            _privateChatWindows[nick].MessageReceived(message);
        }

        /// <summary>
        /// Creates a new PrivateChatWindow from a user card.
        /// </summary>
        /// <param name="userCard">User card to use while creating window</param>
        /// <returns>Created window</returns>
        private PrivateChatWindow CreatePrivateChatWindow(UserCardControl userCard)
        {
            var window = new PrivateChatWindow(_controller)
            {
                CurrentUserNick = txtNick.Text,
                CurrentUserStatus = GetCurrentUserStatus(),
                CurrentUserAvatar = imgCurrentUserAvatar.Source,
                RemoteUserNick = userCard.UserNick,
                RemoteUserStatus = userCard.UserStatus,
                RemoteUserAvatar = userCard.AvatarImageSource
            };
            window.Closed += PrivateChatWindow_Closed;
            window.Show();
            return window;
        }

        /// <summary>
        /// Adds user to user list in right area of the window.
        /// </summary>
        /// <param name="userInfo">New user informations</param>
        private void AddUserToListInternal(UserInfo userInfo)
        {
            //Do not add the current user (that is using the application) to user list
            if (userInfo.Nick == CurrentUserInfo.Nick)
            {
                return;
            }

            //Do not add user to list if it is already exists.
            if (FindUserInList(userInfo.Nick) != null)
            {
                return;
            }

            //Find correct order (by name) to insert the user
            var orderedIndex = 0;
            foreach (UserCardControl userCardControl in spUsers.Children)
            {
                if (userInfo.Nick.CompareTo(userCardControl.UserNick) < 0)
                {
                    break;
                }
                orderedIndex++;
            }

            //Create user control
            var userCard = new UserCardControl
            {
                UserNick = userInfo.Nick,
                UserStatus = userInfo.Status,
                AvatarBytes = userInfo.AvatarBytes,
                Height = 60
            };
            userCard.MouseDoubleClick += UserCard_MouseDoubleClick;

            //Insert user to user list
            spUsers.Children.Insert(
                orderedIndex,
                userCard
                );

            //Enable private messaging window if any open with that user
            if (_privateChatWindows.ContainsKey(userInfo.Nick))
            {
                _privateChatWindows[userInfo.Nick].UserLoggedIn();
                _privateChatWindows[userInfo.Nick].RemoteUserStatus = userInfo.Status;
                _privateChatWindows[userInfo.Nick].RemoteUserAvatar = userCard.AvatarImageSource;
            }
        }

        /// <summary>
        /// Removes an existing user from user list.
        /// </summary>
        /// <param name="nick"></param>
        private void RemoveUserFromListInternal(string nick)
        {
            //Enable private messaging window is any open with that user
            if (_privateChatWindows.ContainsKey(nick))
            {
                _privateChatWindows[nick].UserLoggedOut();
            }

            //Find user in list
            var userCard = FindUserInList(nick);

            //Remove if found
            if (userCard != null)
            {
                spUsers.Children.Remove(userCard);
                userCard.MouseDoubleClick -= UserCard_MouseDoubleClick;
            }
        }

        /// <summary>
        /// Changes status of a user in user list.
        /// </summary>
        /// <param name="nick">Nick of the user</param>
        /// <param name="newStatus">New status of the user</param>
        public void OnUserStatusChangeInternal(string nick, UserStatus newStatus)
        {
            //Find user in list
            var userCard = FindUserInList(nick);

            //Change status of user if found
            if (userCard != null)
            {
                userCard.UserStatus = newStatus;
            }

            //Change status of user if any private chat window is open
            if (_privateChatWindows.ContainsKey(nick))
            {
                _privateChatWindows[nick].RemoteUserStatus = newStatus;
            }
        }

        /// <summary>
        /// Searches a user (by nick) in user list and gets user card control of user.
        /// </summary>
        /// <param name="nick">Nick to search</param>
        /// <returns>Found user card of user</returns>
        private UserCardControl FindUserInList(string nick)
        {
            return spUsers.Children.Cast<UserCardControl>().FirstOrDefault(userCardControl => userCardControl.UserNick == nick);
        }

        /// <summary>
        /// Changes avatar of the current user by a file.
        /// </summary>
        /// <param name="avatarPath">File path of new avatar</param>
        private void ChangeCurrentUserAvatar(string avatarPath)
        {
            imgLoginAvatar.Source = new BitmapImage(new Uri(avatarPath));
            imgCurrentUserAvatar.Source = imgLoginAvatar.Source;
            _userPreferences.AvatarFile = avatarPath;
        }

        /// <summary>
        /// Gets status of the current user from combobox.
        /// </summary>
        /// <returns>Status of current user</returns>
        private UserStatus GetCurrentUserStatus()
        {
            switch (cmbCurrentUserStatus.SelectedIndex)
            {
                case 0:
                    return UserStatus.Available;
                case 1:
                    return UserStatus.Busy;
                default:
                    return UserStatus.Out;
            }
        }

        /// <summary>
        /// Gets bytes of current user avatar.
        /// </summary>
        /// <returns>Bytes of user avatar file</returns>
        private byte[] GetBytesOfCurrentUserAvatar()
        {
            if (string.IsNullOrEmpty(_userPreferences.AvatarFile))
            {
                return null;
            }

            try
            {
                if (!File.Exists(_userPreferences.AvatarFile))
                {
                    return null;
                }

                return File.ReadAllBytes(_userPreferences.AvatarFile);
            }
            catch (Exception)
            {
                return null;
            }
        }

        #endregion
    }
}