using System;
using System.Diagnostics;
using System.IO.Ports;

namespace Bro.Common.Link
{
    /// <summary>
    /// 串口连接
    /// </summary>
    public class SerialLink : LinkBase
    {
        // 默认串口号
        public const int        DFT_PORT        = 1;
        // 默认波特率
        public const int        DFT_BAUD_RATE   = 9600;

        // 串口号
        public int  Port { get;set;}
        // 波特率
        public int  BaudRate { get;set;}
        // 串口连接
        private SerialPort  SerialPort = new SerialPort();

        public SerialLink()
        {
            IsConn       = false;

            Port        = DFT_PORT;
            BaudRate    = DFT_BAUD_RATE;
        }

        /// <summary>
        /// 打开串口连接
        /// </summary>
        /// <returns></returns>
        public override bool Open()
        {
            if ( SerialPort.IsOpen )
            {
                return true;
            }

            try
            {
                SerialPort.PortName         = "COM" + this.Port;
                SerialPort.BaudRate         = this.BaudRate;
                SerialPort.WriteBufferSize  = this.SendBuffLen;
                SerialPort.ReadBufferSize   = this.RecvBuffLen;

                SerialPort.Open();

                base.IsConn = true;

                return true;
            }
            catch(Exception ex)
            {
                Trace.TraceError("SerialLink:{0} Open fail, ex:{1}-{2}", this.Desp, ex.Message, ex.StackTrace);
            }
        
            return false;
        }

        /// <summary>
        /// 关闭串口连接
        /// </summary>
        public override void Close()
        {
            try
            {
                if ( !SerialPort.IsOpen )
                {
                    return;
                }
            
                SerialPort.Close();
            }
            catch(Exception ex)
            {
                Trace.TraceError("SerialLink:{0} Close fail, ex:{1}-{2}", this.Desp, ex.Message, ex.StackTrace);
            }
        
        }

        /// <summary>
        /// 销毁
        /// </summary>
        public override void Fnit()
        {
            Close();
        }

        /// <summary>
        /// 接收数据
        /// </summary>
        /// <param name="rcvBuf"></param>
        /// <param name="bufLen"></param>
        /// <returns></returns>
        public override int Recv(byte[] rcvBuf, int offset)
        {
            int rcvLen = -1;

            if ( null == rcvBuf )
            {
                return -1;
            }

            try
            {
                var len = rcvBuf.Length - offset;
                if ( len <= 0 )
                {
                    return -1;
                }

                rcvLen = SerialPort.Read(rcvBuf, offset, len);
            }
            catch(Exception ex)
            {
                Trace.TraceError("SerialLink:{0} Recv fail, ex:{1}-{2}", this.Desp, ex.Message, ex.StackTrace);
            }

            return rcvLen;
        }

        /// <summary>
        /// 发送数据
        /// </summary>
        /// <param name="sndBuf"></param>
        /// <param name="offset"></param>
        /// <returns></returns>
        public override bool Send(byte[] sndBuf, int offset, int len)
        {
            if ( null == sndBuf )
            {
                return false;
            }

            try
            {
                SerialPort.Write(sndBuf, offset, len);
                
                return true;
            }
            catch(Exception ex)
            {
                Trace.TraceError("SerialLink:{0} Send fail, ex:{1}-{2}", this.Desp, ex.Message, ex.StackTrace);
            }
            
            return false;
        }
        
    }
}