using System;
using System.Configuration;
using System.Runtime.Remoting;
using System.Collections.Generic;
using System.Runtime.Remoting.Channels;
using System.Runtime.Remoting.Channels.Tcp;

namespace Ease.SvcHost
{
	/// <summary>
	/// Summary description for RemotingHost.
	/// </summary>
	public class RemotingHost
	{
        private HostConfig _config;
        private List<IChannelReceiver> _channels = new List<IChannelReceiver>();

        private string _status = "";
        public string Status
		{
			get { return _status; }
		}

		private void Log(string format, params object[] args)
		{
			if (_status.Length > 0)
				_status += Environment.NewLine;

			_status += string.Format(format, args);
		}

		public RemotingHost()
		{
            _config = HostConfig.GetConfig();
            if (_config == null)
                throw new ConfigurationErrorsException("ServiceHost configuration missing.");
		}

        private void InvokeMethod(HostConfig.MethodNode node)
        {
            try
            {
                Log("Invoking method: " + node.Method.DeclaringType.FullName + "." + node.Method.Name + "()");
                node.Method.Invoke(null, null);
                Log("Method Executed."); 
            }
            catch (Exception e)
            {
                Log("Error: {0}", e.ToString());
            }  
        }

        public void Start()
        {
            _status = "";

            if (_config.Port != 0)
            {
                try
                {
                    TcpServerChannel channel = new TcpServerChannel("RemotingListener", _config.Port);
                    ChannelServices.RegisterChannel(channel, false);
                    Log("Tcp channel registered on port {0}.", _config.Port);
                    Log("Custome Errors: {0}", _config.ErrorModes);
                    Log("");

                    _channels.Add(channel);
                }
                catch (Exception e)
                {
                    Log("Error Registering Channel: {0}.", e.Message);
                }
            }
            
            // Turn off custom errors (comment if required) 
            RemotingConfiguration.CustomErrorsMode = _config.ErrorModes;

            //container assemblies
            foreach (HostConfig.ContainersNode containers in _config.Containers)
            {
                Log("Loading Containers Assembly: {0}", containers.Assembly.FullName);

                // initializers
                foreach (HostConfig.MethodNode node in containers.Initializers)
                {
                    InvokeMethod(node);
                }

                Log("Activation Mode: {0}", containers.ActivationMode);
                Log("");
                Log("Start-Assembly >>");

                foreach (Type type in containers.Types)
                {
                    WellKnownServiceTypeEntry entry = new WellKnownServiceTypeEntry(type, type.FullName, containers.ActivationMode);
                    RemotingConfiguration.RegisterWellKnownServiceType(type, type.FullName, containers.ActivationMode);
                    Log("Service -> {0}", type.FullName);
                }

                Log("<< End-Assembly");
            }
        }

        public void Stop()
        {
            _status = "";

            if (_channels.Count > 0)
            {
                Log("Stopping channels ...");
                foreach (IChannelReceiver channel in _channels)
                {
                    try
                    {
                        channel.StopListening(null);
                    }
                    catch (Exception e)
                    {
                        Log("Error stopping channel: {0}. {1}", channel.ChannelName, e.Message);
                    }
                }
            }
            foreach (HostConfig.ContainersNode assembly in _config.Containers)
            {
                if (assembly.Finalizers.Count > 0)
                {
                    Log("{0} Finalizers ...", assembly.Assembly.GetName().Name);
                    foreach (HostConfig.MethodNode node in assembly.Finalizers)
                    {
                        InvokeMethod(node);
                    }
                }
            }

            Log("Host Stopped.");
        }
	}
}