using System;
using System.IO.Ports;
using Aitex.Core.RT.Event;
using Aitex.Core.RT.Log;

namespace MECF.Framework.Common.Communications
{
    public abstract class SerialPortConnectionBase : IConnection
    {
        public string Address
        {
            get { return _address; }
        }

        public bool IsConnected
        {
            get { return _port.IsOpen(); }
        }

        public bool Connect()
        {
            return _port.Open();
        }

        public bool Disconnect()
        {
            _port.Close();
            return true;
        }

        public bool IsBusy
        {
            get { return _activeHandler != null; }
        }

        public bool IsCommunicationError { get; private set; }
        public string LastCommunicationError { get; private set; }

        private AsyncSerialPort _port;

        protected HandlerBase _activeHandler; //set, control, 

        private object _lockerActiveHandler = new object();

        private string _address;

        private bool _isAsciiMode;

        public SerialPortConnectionBase(string port, int baudRate=9600, int dataBits=8, Parity parity = Parity.None, StopBits stopBits = StopBits.One, string newline = "\r", bool isAsciiMode = true)
        {
            _address = port;

            _isAsciiMode = isAsciiMode;

            _port = new AsyncSerialPort(port, baudRate, dataBits, parity, stopBits, newline, isAsciiMode);

            _port.OnDataChanged += _port_OnAsciiDataReceived;
            _port.OnBinaryDataChanged += _port_OnBinaryDataChanged;
            _port.OnErrorHappened += _port_OnErrorHappened;
        }

        public void SetPortAddress(string portName)
        {
            _port.PortName = portName;
        }

        private void _port_OnErrorHappened(string obj)
        {
            //LOG.Error(obj);
        }

        public virtual bool SendMessage(string message)
        {
            if (_port != null && _port.IsOpen())
                return _port.Write(message);

            //LOG.Error($"No connection writing message {message}");
            return false;
        }

        public virtual bool SendMessage(byte[] message)
        {
            if (_port != null && _port.IsOpen())
                return _port.Write(message);
 
            //LOG.Error($"No connection writing message {string.Join(" ", Array.ConvertAll(message, x => x.ToString("X2")))}");
            return false;
        }

        public void Execute(HandlerBase handler)
        {
            if (_activeHandler != null)
                return;

            if (handler == null)
                return;

            if (_port.IsOpen())
            {
                lock (_lockerActiveHandler)
                {
                    _activeHandler = handler;
                    _activeHandler.SetState(EnumHandlerState.Sent);
                }

                bool sendResult = _isAsciiMode ? SendMessage(handler.SendText) : SendMessage(handler.SendBinary);
                if (!sendResult) 
                {
                    lock (_lockerActiveHandler)
                    {
                        _activeHandler = null;
                    }
                }
 
            }
        }

        protected virtual MessageBase ParseResponse(string rawMessage)
        {
            return null;
        }

        protected virtual MessageBase ParseResponse(byte[] rawMessage)
        {
            return null;
        }

        protected virtual void OnEventArrived(MessageBase msg)
        {

        }

        protected virtual void ActiveHandlerProceedMessage(MessageBase msg)
        {
            lock (_lockerActiveHandler)
            {
                if (_activeHandler != null)
                {
                    if (msg.IsFormatError || (_activeHandler.HandleMessage(msg, out bool transactionComplete) && transactionComplete))
                    {
                        _activeHandler = null;
                    }
                }
            }
        }

        private void ProceedTransactionMessage(MessageBase msg)
        {
            if (msg == null || msg.IsFormatError)
            {
                SetCommunicationError(true, "received invalid response message.");
                return;
            }

            if (msg.IsEvent)
            {
                OnEventArrived(msg);
                return;
            }

            //当前活动交互会话，继续执行
            ActiveHandlerProceedMessage(msg);
        }

        private void _port_OnBinaryDataChanged(byte[] binaryData)
        {
            MessageBase msg = ParseResponse(binaryData);
            ProceedTransactionMessage(msg);
        }

        private void _port_OnAsciiDataReceived(string oneLineMessage)
        {
            MessageBase msg = ParseResponse(oneLineMessage);
            ProceedTransactionMessage(msg);
        }

        public HandlerBase MonitorTimeout()
        {
            HandlerBase result = null;
            lock (_lockerActiveHandler)
            {
                if (_activeHandler!=null && _activeHandler.CheckTimeout())
                {
                    result = _activeHandler;
                    _activeHandler = null;

                    SetCommunicationError(true, "receive response timeout");
                }
            }

            return result;
        }

        public void SetCommunicationError(bool isError, string reason)
        {
            IsCommunicationError = isError;
            LastCommunicationError = reason;
        }
    }
}