// Copyright (c) Microsoft Corporation
// The Microsoft Corporation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
#pragma warning disable SA1310 // FieldNamesMustNotContainUnderscore

using System;
using System.Diagnostics;
using System.Threading;
using System.Threading.Tasks;
using System.Windows;
using interop;
using ManagedCommon;
using PowerAccent.Core.Tools;
using PowerAccent.UI;

namespace PowerAccent;

internal static class Program
{
    private const string PROGRAM_NAME = "PowerAccent";
    private const string PROGRAM_APP_NAME = "PowerToys.PowerAccent";
    private static App _application;
    private static int _powerToysRunnerPid;
    private static CancellationTokenSource _tokenSource = new CancellationTokenSource();

    [STAThread]
    public static void Main(string[] args)
    {
        _ = new Mutex(true, PROGRAM_APP_NAME, out bool instantiated);

        if (instantiated)
        {
            Arguments(args);

            InitEvents();

            _application = new App();
            _application.InitializeComponent();
            _application.Run();
        }
        else
        {
            Logger.LogWarning("Another running PowerAccent instance was detected. Exiting PowerAccent");
        }
    }

    private static void InitEvents()
    {
        Task.Run(
            () =>
            {
                EventWaitHandle eventHandle = new EventWaitHandle(false, EventResetMode.AutoReset, Constants.PowerAccentExitEvent());
                if (eventHandle.WaitOne())
                {
                    Terminate();
                }
            }, _tokenSource.Token);
    }

    private static void Arguments(string[] args)
    {
        if (args?.Length > 0)
        {
            try
            {
                _ = int.TryParse(args[0], out _powerToysRunnerPid);

                Logger.LogInfo($"PowerAccent started from the PowerToys Runner. Runner pid={_powerToysRunnerPid}");

                RunnerHelper.WaitForPowerToysRunner(_powerToysRunnerPid, () =>
                {
                    Logger.LogInfo("PowerToys Runner exited. Exiting PowerAccent");
                    Terminate();
                });
            }
            catch (Exception ex)
            {
                Debug.WriteLine(ex.Message);
            }
        }
        else
        {
            Logger.LogInfo($"PowerAccent started detached from PowerToys Runner.");
            _powerToysRunnerPid = -1;
        }
    }

    private static void Terminate()
    {
        Application.Current.Dispatcher.BeginInvoke(() =>
        {
            _tokenSource.Cancel();
            Application.Current.Shutdown();
        });
    }
}