using System;
using System.IO;
using System.Reflection;
using System.Security.Cryptography.X509Certificates;
using InABox.Core;
using InABox.IPC;
using InABox.Logging;
using InABox.Rpc;

namespace PRSServer
{
    public interface IEngine
    {
        string ServiceName { get; set; }

        string Version { get; set; }
        void Run();
        void Stop();

        void Configure(Server settings);

        PortStatus[] PortStatusList();
    }

    public abstract class Engine<TProperties> : IEngine where TProperties : ServerProperties
    {
        
        private RpcServerPipeTransport _enginemanager;

        public TProperties Properties { get; private set; }
        public abstract void Run();
        public abstract void Stop();

        public virtual PortStatus[] PortStatusList()
        {
            return new PortStatus[] { };
        }

        public string ServiceName { get; set; }

        public string Version { get; set; }

        protected string AppDataFolder { get; set; }

        public virtual void Configure(Server server)
        {
            Properties = server.Properties as TProperties;

            AppDataFolder = GetPath(server.Key);
            MainLogger.AddLogger(new LogFileLogger(AppDataFolder));
            MainLogger.AddLogger(new NamedPipeLogger(server.Key));
            
            _enginemanager = new RpcServerPipeTransport($"{ServiceName}M");
            _enginemanager.AddHandler<IEngine, PortStatusCommand, PortStatusParameters, PortStatusResult>(new PortStatusHandler(this));
            _enginemanager.AfterMessage += (transport, args) => MainLogger.Send(LogType.Information,"",$"Engine Manager Message: {args.Message?.Command}");
            _enginemanager.Start();
        }

        public static string GetPath(string key)
        {
            if (Assembly.GetEntryAssembly() != null)
                return Path.Combine(
                    Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData),
                    Path.GetFileNameWithoutExtension(Assembly.GetEntryAssembly().Location),
                    key
                );
            return Path.Combine(
                Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData),
                Path.GetFileNameWithoutExtension(Assembly.GetExecutingAssembly().Location),
                key
            );
        }
        
        public static X509Certificate2? LoadCertificate(string filename)
        {
            if (!String.IsNullOrWhiteSpace(filename))
            {
                Logger.Send(LogType.Information, "", "Certificate FileName is {0}", filename);
                if (File.Exists(filename))
                {
                    Logger.Send(LogType.Information, "", "Certificate found; verifying HTTPS Certificate");
                    try
                    {
                        var certificate = new X509Certificate2(filename);
                        if (certificate.NotAfter > DateTime.Now)
                        {
                            
                            var names = CertificateEngine.GetDnsNames(certificate);
                            Logger.Send(LogType.Information, "", $"Certificate valid for {string.Join(',', names)}");
                            return certificate;
                        }
                        else
                        {
                            Logger.Send(LogType.Error, "", "HTTPS Certificate has expired, using HTTP instead");
                        }
                    }
                    catch (Exception)
                    {
                        Logger.Send(LogType.Error, "", "Error validating HTTPS Certificate, using HTTP instead");
                    }
                }
                else
                    Logger.Send(LogType.Error, "", "Certificate File does not exist!");
            }
            return null;
        }

    }
}