using System;
using System.Diagnostics;
using System.IO;
using System.ServiceProcess;

namespace PCMonitor.Installer {

    /// <summary>
    /// Windows Service Installer
    /// Menginstall/Uninstall Agent sebagai Windows Service
    /// </summary>
    class ServiceInstaller {
        private const string ServiceName = "PCMonitorAgent";
        private const string ServiceDisplayName = "PC Monitor Agent";
        private const string ServiceDescription = "Monitoring aktivitas PC - Agent Service";

        // Entry point removed - use Program.cs Main instead
        // Installation is called from INSTALL.bat or installer scripts
        
        public static void InstallService() {
            Console.WriteLine("Installing PC Monitor Agent Service...");

            try {
                // Check if service already exists
                using (var sc = new ServiceController(ServiceName)) {
                    Console.WriteLine("Service already installed!");
                    return;
                }
            } catch (InvalidOperationException) {
                // Service doesn't exist, proceed with installation
            }

            string exePath = System.Reflection.Assembly.GetExecutingAssembly().Location;
            exePath = Path.Combine(Path.GetDirectoryName(exePath), "PCMonitorAgent.exe");

            // Create service installation command using SC
            string arguments = $"create \"{ServiceName}\" binPath= \"{exePath}\" " +
                $"DisplayName= \"{ServiceDisplayName}\" start= auto";

            ExecuteCommand("sc", arguments);

            // Set service description
            arguments = $"description \"{ServiceName}\" \"{ServiceDescription}\"";
            ExecuteCommand("sc", arguments);

            // Create directory for config and logs
            string programDataPath = Path.Combine(
                Environment.GetFolderPath(Environment.SpecialFolder.CommonApplicationData),
                "PCMonitor"
            );
            Directory.CreateDirectory(programDataPath);
            Directory.CreateDirectory(Path.Combine(programDataPath, "Logs"));
            Directory.CreateDirectory(Path.Combine(programDataPath, "Screenshots"));

            Console.WriteLine("Service installed successfully!");
            Console.WriteLine($"Service Name: {ServiceName}");
            Console.WriteLine($"Display Name: {ServiceDisplayName}");
            Console.WriteLine("Run 'PCMonitorInstaller.exe start' to start the service");
        }

        public static void UninstallService() {
            Console.WriteLine("Uninstalling PC Monitor Agent Service...");

            try {
                // Stop service first
                using (var sc = new ServiceController(ServiceName)) {
                    if (sc.Status != ServiceControllerStatus.Stopped) {
                        Console.WriteLine("Stopping service...");
                        sc.Stop();
                        sc.WaitForStatus(ServiceControllerStatus.Stopped, TimeSpan.FromSeconds(30));
                    }
                }
            } catch (InvalidOperationException) {
                // Service doesn't exist
            }

            // Delete service
            string arguments = $"delete \"{ServiceName}\"";
            ExecuteCommand("sc", arguments);

            Console.WriteLine("Service uninstalled successfully!");
        }

        public static void StartService() {
            Console.WriteLine("Starting PC Monitor Agent Service...");

            try {
                using (var sc = new ServiceController(ServiceName)) {
                    if (sc.Status == ServiceControllerStatus.Running) {
                        Console.WriteLine("Service is already running!");
                        return;
                    }

                    sc.Start();
                    sc.WaitForStatus(ServiceControllerStatus.Running, TimeSpan.FromSeconds(30));
                    Console.WriteLine("Service started successfully!");
                }
            } catch (Exception ex) {
                Console.WriteLine($"Error starting service: {ex.Message}");
            }
        }

        public static void StopService() {
            Console.WriteLine("Stopping PC Monitor Agent Service...");

            try {
                using (var sc = new ServiceController(ServiceName)) {
                    if (sc.Status == ServiceControllerStatus.Stopped) {
                        Console.WriteLine("Service is already stopped!");
                        return;
                    }

                    sc.Stop();
                    sc.WaitForStatus(ServiceControllerStatus.Stopped, TimeSpan.FromSeconds(30));
                    Console.WriteLine("Service stopped successfully!");
                }
            } catch (Exception ex) {
                Console.WriteLine($"Error stopping service: {ex.Message}");
            }
        }

        public static void ShowStatus() {
            try {
                using (var sc = new ServiceController(ServiceName)) {
                    Console.WriteLine($"Service: {ServiceDisplayName}");
                    Console.WriteLine($"Status: {sc.Status}");
                    Console.WriteLine($"Can Handle Pause/Continue: {sc.CanPauseAndContinue}");
                    Console.WriteLine($"Service Type: {sc.ServiceType}");
                }
            } catch (InvalidOperationException) {
                Console.WriteLine("Service is not installed!");
            }
        }

        static void ExecuteCommand(string command, string arguments) {
            var process = new Process {
                StartInfo = new ProcessStartInfo {
                    FileName = command,
                    Arguments = arguments,
                    UseShellExecute = false,
                    RedirectStandardOutput = true,
                    RedirectStandardError = true,
                    CreateNoWindow = true,
                    Verb = "runas"
                }
            };

            try {
                process.Start();
                process.WaitForExit();
                
                if (process.ExitCode != 0) {
                    string error = process.StandardError.ReadToEnd();
                    throw new Exception(error);
                }
            } finally {
                process?.Dispose();
            }
        }

        static void ShowUsage() {
            Console.WriteLine("PC Monitor Agent Installer");
            Console.WriteLine("Version 1.0");
            Console.WriteLine();
            Console.WriteLine("Usage: PCMonitorInstaller.exe <command>");
            Console.WriteLine();
            Console.WriteLine("Commands:");
            Console.WriteLine("  install   - Install service");
            Console.WriteLine("  uninstall - Uninstall service");
            Console.WriteLine("  start     - Start service");
            Console.WriteLine("  stop      - Stop service");
            Console.WriteLine("  status    - Show service status");
            Console.WriteLine();
            Console.WriteLine("Note: Run with Administrator privileges");
        }
    }
}