using CommandLine;
using System;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using RedisManager.Commands;
using Crayon;

namespace RedisManager
{
    /// <summary>
    /// Main entry point for the RedisManager application.
    /// Supports service (daemon) mode and client mode only.
    /// </summary>
    class Program
    {
        /// <summary>
        /// Main entry point that determines the operational mode based on command line arguments.
        /// </summary>
        /// <param name="args">Command line arguments</param>
        /// <returns>Exit code (0 for success, non-zero for errors)</returns>
        static async Task<int> Main(string[] args)
        {
            // No arguments: run as a daemon (service mode)
            // Service mode: allow optional --config <path>
            if (args.Length == 0 || (args.Length >= 2 && args[0] == "--config"))
            {
                string configPath = null;
                if (args.Length >= 2 && args[0] == "--config")
                {
                    configPath = args[1];
                    // Remove --config and path from args for service mode
                    args = args.Skip(2).ToArray();
                }
                return await RunServiceMode();
            } // Standalone mode removed: all commands require daemon/service.

            // With arguments: try to connect to the daemon (client mode)
            var client = new RedisManagerClient();
            var clientResult = await client.ExecuteCommandAsync(args);

            // A specific exit code (2) from the client indicates the service is not running
            if (clientResult == 2)
            {
                // Allow help output even if no daemon and no --instance
                bool wantsHelp = args.Any(arg => arg == "help" || arg == "--help" || arg == "-h");
                if (!wantsHelp)
                {
                    Console.WriteLine(Output.Red("Error: RedisManager daemon/service is not running. Please start the service (no arguments) and retry your command."));
                }
            }

            // Return the result from the client (0 for success, 1 for other errors)
            return clientResult;
        }

        /// <summary>
        /// Runs RedisManager in service mode, starting a TCP server that accepts client connections.
        /// The service runs indefinitely until interrupted by Ctrl+C or other termination signals.
        /// </summary>
        /// <returns>Exit code (0 for successful shutdown)</returns>
        static async Task<int> RunServiceMode()
        {
            Console.WriteLine("Starting RedisManager Service...");
            var service = new RedisManagerService();
            await service.StartAsync();

            // Block the main thread until Ctrl+C is pressed
            var cts = new System.Threading.CancellationTokenSource();
            Console.CancelKeyPress += (sender, e) => {
                e.Cancel = true;
                cts.Cancel();
            };
            Console.WriteLine("RedisManager daemon is running. Press Ctrl+C to exit.");
            try
            {
                await Task.Delay(-1, cts.Token);
            }
            catch (OperationCanceledException)
            {
                Console.WriteLine("Shutting down RedisManager Service...");
            }
            await service.StopAsync();
            return 0;
        }
    }
}