prs/prs.logikal/LogikalListener.cs

using System;
using System.Collections.Generic;
using System.Linq;
using H.Formatters;
using H.Pipes;
using InABox.Logikal;
using Newtonsoft.Json;

namespace PRSLogikal
{
    public class LogikalListener : IDisposable
    {
        private PipeServer<LogikalMessage> _server;

        public LogikalServer Server { get; set; }

        public event LogikalLogEvent Log;

        private void DoLog(string message) => Log?.Invoke(this, new LogikalLogArguments(message));
        
        
        public event EventHandler Disconnecting; 
        
        public LogikalListener()
        {
            methods = new Dictionary<LogikalMethod, ILogikalMethodInfo>
            {
                { LogikalMethod.Error, new LogikalMethodInfo<LogikalErrorRequest>(DoError) },
                { LogikalMethod.Connect, new LogikalMethodInfo<LogikalConnectRequest>(Connect) },
                { LogikalMethod.Login, new LogikalMethodInfo<LogikalLoginRequest>(Login) },
                { LogikalMethod.Logout, new LogikalMethodInfo<LogikalLogoutRequest>(Logout) },
                { LogikalMethod.Disconnect, new LogikalMethodInfo<LogikalDisconnectRequest>(Disconnect) },
                { LogikalMethod.ProjectCentres, new LogikalMethodInfo<LogikalProjectCentresRequest>(GetProjectCentres) },
                { LogikalMethod.Projects, new LogikalMethodInfo<LogikalProjectsRequest>(GetProjects) },
                { LogikalMethod.Phases, new LogikalMethodInfo<LogikalPhasesRequest>(GetPhases) },
                { LogikalMethod.Elevations, new LogikalMethodInfo<LogikalElevationsRequest>(GetElevations) },
                { LogikalMethod.Elevation, new LogikalMethodInfo<LogikalElevationRequest>(GetElevation) },
                { LogikalMethod.BOM, new LogikalMethodInfo<LogikalBOMRequest>(GetBOM) },
            };
            
            _server = new PipeServer<LogikalMessage>("$logikal", formatter: new NewtonsoftJsonFormatter());
            
            _server.ClientConnected += (o, args) =>
            {
                DoLog($@"Client is now connected!");
            };
            
            _server.ClientDisconnected += (o, args) =>
            {
                DoLog($@"Client disconnected");
            };
            
            _server.MessageReceived += (sender, args) =>
            {
                DoLog($@"Client says: {args.Message.Method}: {args.Message.Payload}");
                if (methods.TryGetValue(args.Message.Method, out var _info))
                {
                    var _request = FromMessage(_info.Type, args.Message);
                    _info.Action(_request, args.Message.ID);
                }
                else
                    DoError(new LogikalErrorRequest(LogikalStatus.Error, $"Invalid Message Method: {args.Message.Method}: {args.Message.Payload}"), args.Message.ID);
            };
            
            _server.ExceptionOccurred += (sender, args) =>
            {
                DoLog($@"Exception: {args.Exception.Message}");
            };

        }

        private interface ILogikalMethodInfo
        {
            Type Type { get; }
            Action<LogikalRequest,Guid> Action { get; }
        }
        
        private class LogikalMethodInfo<T> : ILogikalMethodInfo where T : LogikalRequest
        {
            public Type Type { get; }

            public Action<LogikalRequest, Guid> Action { get; private set; }
            
            public LogikalMethodInfo(Action<T, Guid> action)
            {
                Type = typeof(T);
                Action = (request,id) => action(request as T,id);
            }
        }

        private Dictionary<LogikalMethod, ILogikalMethodInfo> methods;


        private LogikalRequest FromMessage(Type type, LogikalMessage message)
        {
            try
            {
                LogikalRequest _result = null;
                _result = JsonConvert.DeserializeObject(message.Payload, type) as LogikalRequest;
                if (_result != null)
                    return _result;
                return new LogikalErrorRequest() { Status = LogikalStatus.Error, Message = $"Deserialize Failure: {message.Method}: {message.Payload}" };
            }
            catch (Exception e)
            {
                return new LogikalErrorRequest() { Status = LogikalStatus.Error, Message = $"Exception Deserializing Request: {e.Message}\n{e.StackTrace}" };
            }

        }

        public void Start() => _server.StartAsync();

        public void Stop() => _server.StopAsync();

        private void DoError(LogikalErrorRequest request, Guid messageID)
        {
            var _response = new LogikalErrorResponse() { Status = request.Status, Message = request.Message };
            DoLog($"Server replies: {_response.ToString()}");
            _server.WriteAsync(_response.ToMessage(messageID));
        }

        private void Connect(LogikalConnectRequest request, Guid messageID)
        {
            var _response = Server.Connect(request);
            DoLog($"Server replies: {_response.ToString()}");
            _server.WriteAsync(_response.ToMessage(messageID));
        }
        
        private void Disconnect(LogikalDisconnectRequest request, Guid messageID)
        {
            var _response = Server.Disconnect();
            DoLog($"Server replies: {_response.ToString()}");
            _server.WriteAsync(_response.ToMessage(messageID));   
            Disconnecting?.Invoke(this,EventArgs.Empty);
        }
        
        private void Login(LogikalLoginRequest request, Guid messageID)
        {
            var _response = Server.Login(request);
            DoLog($"Server replies: {_response.ToString()}");
            _server.WriteAsync(_response.ToMessage(messageID));
        }
        
        private void Logout(LogikalLogoutRequest request, Guid messageID)
        {
            var _response = Server.Logout();
            DoLog($"Server replies: {_response.ToString()}");
            _server.WriteAsync(_response.ToMessage(messageID));
        }

        private void GetProjectCentres(LogikalProjectCentresRequest request, Guid messageID)
        {
            var _response = Server.GetProjectCentres(request);
            DoLog($"Server replies: {_response.ToString()}");
            _server.WriteAsync(_response.ToMessage(messageID));
        }

        private void GetProjects(LogikalProjectsRequest request, Guid messageID)
        {
            var _response = Server.GetProjects(request);
            DoLog($"Server replies: {_response.ToString()}");
            _server.WriteAsync(_response.ToMessage(messageID));
        }

        private void GetProject(LogikalProjectRequest request, Guid messageID)
        {
            var _response = Server.GetProject(request);
            DoLog($"Server replies: {_response.ToString()}");
            _server.WriteAsync(_response.ToMessage(messageID));
        }

        private void GetPhases(LogikalPhasesRequest request, Guid messageID)
        {
            var _response = Server.GetPhases(request);
            DoLog($"Server replies: {_response.ToString()}");
            _server.WriteAsync(_response.ToMessage(messageID));
        }
        
                
        private void GetElevations(LogikalElevationsRequest request, Guid messageID)
        {
            var _response = Server.GetElevations(request);
            DoLog($"Server replies: {_response.ToString()}");
            _server.WriteAsync(_response.ToMessage(messageID));
        }
        
        private void GetBOM(LogikalBOMRequest request, Guid messageID)
        {
            var _response = Server.GetBillOfMaterials(request);
            DoLog($"Server replies: {_response.ToString()}");
            _server.WriteAsync(_response.ToMessage(messageID));
        }

        private void GetElevation(LogikalElevationRequest request, Guid messageID)
        {
            var _response = Server.GetElevation(request);
            DoLog($"Server replies: {_response.ToString()}");
            _server.WriteAsync(_response.ToMessage(messageID));
        }

        public void Dispose()
        {
            if (_server != null)
                _ = _server.DisposeAsync().AsTask();
        }
    }
}