using Notifications.Wpf;
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.IO.Ports;
using System.Linq;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Documents;
using System.Windows.Input;
using Tango.Core;
using Tango.Core.Commands;
using Tango.Logging;
using Tango.Settings;
using Tango.SharedUI;
using Tango.SharedUI.Components;
using Tango.SharedUI.Helpers;
using Tango.StubsUtils.Service.UI.Views;

namespace Tango.StubsUtils.Service.UI.ViewModels
{
    public class MainViewVM : ViewModel
    {
        private ProducerConsumerQueue<String> _logsQueue;
        private Thread _logsThread;
        private NotificationManager _notification;

        private ServiceUISettings _settings;
        public ServiceUISettings Settings
        {
            get { return _settings; }
            set { _settings = value; RaisePropertyChangedAuto(); }
        }

        private StubsService _service;
        public StubsService Service
        {
            get { return _service; }
            set { _service = value; RaisePropertyChangedAuto(); }
        }

        private bool _isTrayIconVisible;
        public bool IsTrayIconVisible
        {
            get { return _isTrayIconVisible; }
            set { _isTrayIconVisible = value; RaisePropertyChangedAuto(); }
        }

        private List<String> _availablePorts;
        public List<String> AvailablePorts
        {
            get { return _availablePorts; }
            set { _availablePorts = value; RaisePropertyChangedAuto(); }
        }

        private String _selectedPort;
        public String SelectedPort
        {
            get { return _selectedPort; }
            set { _selectedPort = value; RaisePropertyChangedAuto(); }
        }

        private SimpleStringLogger _logger;
        public SimpleStringLogger Logger
        {
            get { return _logger; }
            set { _logger = value; RaisePropertyChangedAuto(); }
        }

        public RelayCommand ExitCommand { get; set; }
        public RelayCommand OpenCommand { get; set; }
        public RelayCommand RefreshPortsCommand { get; set; }
        public RelayCommand ToggleConnectionCommand { get; set; }
        public RelayCommand ClearLogCommand { get; set; }
        public RelayCommand StartPerformanceTesterCommand { get; set; }

        public MainViewVM()
        {
            ExitCommand = new RelayCommand(ExitApplication);
            OpenCommand = new RelayCommand(OpenMainWindow);
            IsTrayIconVisible = true;
            AvailablePorts = new List<string>();
            RefreshPortsCommand = new RelayCommand(RefreshPorts);
            ToggleConnectionCommand = new RelayCommand(ToggleConnection);
            StartPerformanceTesterCommand = new RelayCommand(StartPerformanceTester);
            ClearLogCommand = new RelayCommand(ClearLog);
            _logsQueue = new ProducerConsumerQueue<string>();

            _logsThread = new Thread(LogsThreadMethod);
            _logsThread.IsBackground = true;
            _logsThread.Start();

            _notification = new NotificationManager();

            Init();
        }

        public async void Init()
        {
            try
            {
                Logger = new SimpleStringLogger() { Enabled = true };
                Logger.LogReceived += Logger_LogReceived;

                LogManager.RegisterLogger(Logger);

                LogManager.Log("Initializing...");
                Settings = SettingsManager.Default.GetOrCreate<ServiceUISettings>();
                SelectedPort = Settings.USBPort;

                RefreshPorts();

                Service = new StubsService();
                Service.CommunicationFailed += Service_CommunicationFailed;
                await Service.Start();

                _notification.Show(new NotificationContent()
                {
                    Title = "Tango Stubs Service",
                    Message = $"Service Started",
                    Type = NotificationType.Success
                });

                if (Settings.AutoConnect)
                {
                    await Task.Delay(2000);
                    ToggleConnection();
                }
            }
            catch (Exception ex)
            {
                LogManager.Log(ex, "Error initializing service.");

                _notification.Show(new NotificationContent()
                {
                    Title = "Tango Stubs Service",
                    Message = $"Initialization Error",
                    Type = NotificationType.Error
                });
            }
        }

        private void Service_CommunicationFailed(object sender, EventArgs e)
        {
            if (IsTrayIconVisible)
            {
                InvokeUI(() => 
                {
                    _notification.Show(new NotificationContent()
                    {
                        Title = "Tango Stubs Service",
                        Message = $"Communication Error",
                        Type = NotificationType.Error
                    });
                });
            }
        }

        private void Logger_LogReceived(object sender, LogItemBase e)
        {
            String message = e.TimeStamp.ToString("HH:mm:ss.ff") + ": " + e.Message;
            _logsQueue.BlockEnqueue(message);
        }

        private void LogsThreadMethod()
        {
            while (true)
            {
                List<String> logs = new List<string>();

                logs.Add(_logsQueue.BlockDequeue());

                while (_logsQueue.Count > 0)
                {
                    logs.Add(_logsQueue.BlockDequeue());
                }

                InvokeUINow(() =>
                {
                    List<Inline> inlines = new List<Inline>();

                    foreach (var log in logs)
                    {
                        inlines.Add(new Run(log));
                        inlines.Add(new LineBreak());
                    }

                    MainView.Instance.paragraphLog.Inlines.AddRange(inlines);

                    if (Mouse.LeftButton != MouseButtonState.Pressed)
                    {
                        MainView.Instance.scrollViewerLogs.ScrollViewer?.ScrollToEnd();
                    }
                });

                Thread.Sleep(200);
            }
        }

        private void ClearLog()
        {
            InvokeUI(() =>
            {
                IsFree = false;
                UIHelper.DoEvents();
                MainView.Instance.paragraphLog.Inlines.Clear();
                IsFree = true;
            });
        }

        private async void OpenMainWindow()
        {
            Application.Current.MainWindow.Visibility = Visibility.Visible;
            await Task.Delay(200);
            Application.Current.MainWindow.WindowState = WindowState.Normal;
            Application.Current.MainWindow.Focus();
            Application.Current.MainWindow.Activate();
            IsTrayIconVisible = false;
        }

        public async void ExitApplication()
        {
            IsFree = false;
            SaveSettings();
            IsTrayIconVisible = false;
            UIHelper.DoEvents();
            await Task.Delay(1000);
            Environment.Exit(0);
        }

        private void RefreshPorts()
        {
            AvailablePorts = SerialPort.GetPortNames().ToList();

            if (SelectedPort == null)
            {
                SelectedPort = AvailablePorts.FirstOrDefault();
            }

            InvalidateRelayCommands();
        }

        private async void ToggleConnection()
        {
            try
            {
                IsFree = false;

                if (!Service.IsConnected)
                {
                    try
                    {
                        await Service.Connect(SelectedPort);
                        SaveSettings();

                        if (IsTrayIconVisible)
                        {
                            _notification.Show(new NotificationContent()
                            {
                                Title = "Tango Stubs Service",
                                Message = $"Connected ({SelectedPort})",
                                Type = NotificationType.Success
                            });
                        }
                    }
                    catch (Exception ex)
                    {
                        LogManager.Log(ex, "Error connecting to the specified serial port.");

                        if (IsTrayIconVisible)
                        {
                            _notification.Show(new NotificationContent()
                            {
                                Title = "Tango Stubs Service",
                                Message = $"Connection Error ({SelectedPort})",
                                Type = NotificationType.Error
                            });
                        }
                    }
                }
                else
                {
                    try
                    {
                        await Service.Disconnect();
                    }
                    catch (Exception ex)
                    {
                        LogManager.Log(ex, "Error disconnecting from the specified serial port.");
                    }
                }
            }
            finally
            {
                IsFree = true;
            }
        }

        private void SaveSettings()
        {
            Settings.USBPort = SelectedPort;
            Settings.Save();
        }

        private void StartPerformanceTester()
        {
            Process.Start("tangostub_perf.exe");
        }
    }
}