using System;
using System.Collections.Generic;
using System.Data.SqlClient;
using System.Diagnostics;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Tango.Core;
using Tango.Core.Commands;
using Tango.Core.Helpers;
using Tango.PPC.Common;
using Tango.PPC.Common.Application;
using Tango.PPC.Common.MachineSetup;
using Tango.PPC.Common.Navigation;
using Tango.PPC.UI.ViewsContracts;
using Tango.Settings;
using Tango.SharedUI.Helpers;
using Tango.SQLExaminer;

namespace Tango.PPC.UI.ViewModels
{
    /// <summary>
    /// Represents the machine setup view ViewModel.
    /// </summary>
    /// <seealso cref="Tango.PPC.Common.PPCViewModel{Tango.PPC.UI.ViewsContracts.IMachineSetupView}" />
    public class MachineSetupViewVM : PPCViewModel<IMachineSetupView>
    {
        /// <summary>
        /// Represents the various machine setup view states.
        /// </summary>
        public enum MachineSetupStates
        {
            None,
            Working,
            Completed,
            Failed,
        }

        private MachineSetupResult _setup_result;

        #region Properties

        /// <summary>
        /// Gets or sets the machine setup manager.
        /// </summary>
        public IMachineSetupManager MachineSetupManager { get; set; }

        private String _serialNumber;
        /// <summary>
        /// Gets or sets the serial number.
        /// </summary>
        public String SerialNumber
        {
            get { return _serialNumber; }
            set { _serialNumber = value; RaisePropertyChangedAuto(); InvalidateRelayCommands(); }
        }

        private String _hostAddress;
        /// <summary>
        /// Gets or sets the host address.
        /// </summary>
        public String HostAddress
        {
            get { return _hostAddress; }
            set { _hostAddress = value; RaisePropertyChangedAuto(); InvalidateRelayCommands(); }
        }

        private String _log;
        /// <summary>
        /// Gets or sets the log.
        /// </summary>
        public String Log
        {
            get { return _log; }
            set { _log = value; RaisePropertyChangedAuto(); }
        }

        private MachineSetupStates _state;
        /// <summary>
        /// Gets or sets the state.
        /// </summary>
        public MachineSetupStates State
        {
            get { return _state; }
            set { _state = value; RaisePropertyChangedAuto(); InvalidateRelayCommands(); }
        }

        #endregion

        #region Commands

        /// <summary>
        /// Gets or sets the start command.
        /// </summary>
        public RelayCommand StartCommand { get; set; }

        /// <summary>
        /// Gets or sets the complete command.
        /// </summary>
        public RelayCommand CompleteCommand { get; set; }

        #endregion

        #region Constructors

        /// <summary>
        /// Initializes a new instance of the <see cref="MachineSetupViewVM"/> class.
        /// </summary>
        /// <param name="applicationManager">The application manager.</param>
        /// <param name="machineSetupManager">The machine setup manager.</param>
        public MachineSetupViewVM(IPPCApplicationManager applicationManager, IMachineSetupManager machineSetupManager)
        {
            MachineSetupManager = machineSetupManager;
            MachineSetupManager.ProgressLog += (x, msg) => AppendLog(msg);
            MachineSetupManager.ProgressStep += (x, step) => AppendLog(Environment.NewLine + "-----------" + step.ToDescription().ToUpper() + "-----------" + Environment.NewLine);

            HostAddress = "localhost\\SQLEXPRESS";
            SerialNumber = "1111";

            StartCommand = new RelayCommand(StartSetup, () => !String.IsNullOrWhiteSpace(HostAddress) && !String.IsNullOrWhiteSpace(SerialNumber) && State == MachineSetupStates.None);
            CompleteCommand = new RelayCommand(CompleteSetup, () => State == MachineSetupStates.Completed);

            applicationManager.SetupRequired += ApplicationManager_SetupRequired;
        }

        #endregion

        #region Event Handlers

        /// <summary>
        /// Handles the SetupRequired event of the ApplicationManager.
        /// </summary>
        /// <param name="sender">The source of the event.</param>
        /// <param name="e">The <see cref="EventArgs"/> instance containing the event data.</param>
        private void ApplicationManager_SetupRequired(object sender, EventArgs e)
        {
            LogManager.Log("SetupRequired event received. Navigating to MachineSetupView...");
            NavigationManager.NavigateTo(NavigationView.MachineSetupView);
        }

        #endregion

        #region Private Methods

        /// <summary>
        /// Appends the log.
        /// </summary>
        /// <param name="msg">The MSG.</param>
        private void AppendLog(String msg)
        {
            if (msg != null && !msg.Contains("SQL Examiner"))
            {
                InvokeUI(() =>
                {
                    View.AppendLog(msg + Environment.NewLine);
                });
            }
        }

        /// <summary>
        /// Starts the setup.
        /// </summary>
        private async void StartSetup()
        {
            LogManager.Log("Starting machine setup...");

            State = MachineSetupStates.Working;

            try
            {
                _setup_result = await MachineSetupManager.Setup(SerialNumber, HostAddress);
                Settings.ApplicationState = ApplicationStates.SemiSetup;
                Settings.Save();
                State = MachineSetupStates.Completed;

                LogManager.Log("Machine setup completed.");
            }
            catch (Exception ex)
            {
                LogManager.Log(ex, "Machine setup failed.");
                State = MachineSetupStates.Failed;
                await NotificationProvider.ShowInfo(ex.Message);
            }
        }

        /// <summary>
        /// Completes the setup.
        /// </summary>
        private void CompleteSetup()
        {
            String updater_exe = AssemblyHelper.GetCurrentAssemblyFolder() + "\\Tango.PPC.Updater.exe";

            LogManager.Log("Completing machine setup...");
            LogManager.Log($"Executing '{updater_exe}' with arguments '{_setup_result.UpdatePackagePath}'...");
            Process.Start(updater_exe, _setup_result.UpdatePackagePath);
            LogManager.Log("Terminating application process!");
            Environment.Exit(0);
        }

        #endregion
    }
}