namespace RadeonResetBugFixService
{
    using Microsoft.Win32;
    using System;
    using System.Security.Principal;
    using System.ServiceProcess;
    using ThirdParty.ServiceHelpers;

    public static class Program
    {
        /// <summary>
        /// The main entry point for the application.
        /// </summary>
        public static int Main(string[] args)
        {
            if (Environment.UserInteractive)
            {
                if (!HasAdministratorPrivileges())
                {
                    Console.Error.WriteLine("Access Denied.");
                    Console.Error.WriteLine("Administrator permissions are  needed to use the selected options.");
                    Console.Error.WriteLine("Use an administrator command prompt to complete these tasks.");
                    return 740; // ERROR_ELEVATION_REQUIRED
                }

                MainConsole(args);
                return 0;
            }
            else
            {
                return MainService();
            }
        }

        private static int MainService()
        {
            ServiceBase[] ServicesToRun;
            ServicesToRun = new ServiceBase[]
            {
                new RadeonResetBugFixService()
            };
            ServiceBase.Run(ServicesToRun);

            return 0;
        }

        private static void MainConsole(string[] args)
        {
            if (args.Length != 1)
            {
                ShowHelp();
                return;
            }

            switch (args[0].ToLowerInvariant())
            {
                case "install":
                    DoInstall();
                    return;
                case "uninstall":
                    DoUninstall();
                    return;
                case "startup":
                    DoStartup();
                    return;
                case "shutdown":
                    DoShutdown();
                    return;
                default:
                    ShowHelp();
                    return;
            }
        }

        private static void ShowHelp()
        {
            var exeName = Environment.GetCommandLineArgs()[0];
            Console.WriteLine("Usage:");
            Console.WriteLine($"\t{exeName} install");
            Console.WriteLine("\t\tInstalls service");
            Console.WriteLine($"\t{exeName} uninstall");
            Console.WriteLine("\t\tUninstalls service");
            Console.WriteLine($"\t{exeName} startup");
            Console.WriteLine("\t\tPerforms startup sequence");
            Console.WriteLine($"\t{exeName} shutdown");
            Console.WriteLine("\t\tPerforms shutdown sequence");
        }

        private static void DoInstall()
        {
            Console.WriteLine("Setting registry values...");

            // Prevent Windows from killing services that take up to 300 seconds to shutdown
            Registry.SetValue(@"HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control", "WaitToKillServiceTimeout", (int)Constants.ServiceTimeout.TotalMilliseconds, RegistryValueKind.String);

            // Disable fast restart
            Registry.SetValue(@"HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Power", "HiberbootEnabled", 0, RegistryValueKind.DWord);

            // Allow interactive services (FixMonitorTask only works correctly in interactive mode)
            Registry.SetValue(@"HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Windows", "NoInteractiveServices", 0, RegistryValueKind.DWord);

            Console.WriteLine("Installing service...");
            ServiceHelpers.InstallService(nameof(RadeonResetBugFixService), typeof(RadeonResetBugFixService));
            Console.WriteLine("Starting service...");
            ServiceHelpers.StartService(nameof(RadeonResetBugFixService), typeof(RadeonResetBugFixService));
            Console.WriteLine("Started service");
        }

        private static void DoUninstall()
        {
            Console.WriteLine("Stopping service...");
            ServiceHelpers.StopService(nameof(RadeonResetBugFixService), typeof(RadeonResetBugFixService));
            Console.WriteLine("Uninstalling service...");
            ServiceHelpers.UninstallService(nameof(RadeonResetBugFixService), typeof(RadeonResetBugFixService));
            Console.WriteLine("Uninstalled");
        }

        private static void DoStartup()
        {
            new MainHandler().HandleStartup("Program.DoStartup");
        }

        private static void DoShutdown()
        {
            new MainHandler().HandleShutdown("Program.DoShutdown");
        }

        // Code taken from https://stackoverflow.com/a/2679654
        private static bool HasAdministratorPrivileges()
        {
            WindowsIdentity id = WindowsIdentity.GetCurrent();
            WindowsPrincipal principal = new WindowsPrincipal(id);
            return principal.IsInRole(WindowsBuiltInRole.Administrator);
        }
    }
}