FCC/Devices/Pumps/Gilbarco_Pump/MessageCutter.cs

using Edge.Core.Processor;
using Edge.Core.IndustryStandardInterface.Pump;
using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Edge.Core.Parser.BinaryParser.Util;
using Edge.Core.Processor.Communicator;

namespace Gilbarco_Pump
{
    public class MessageCutter : IMessageCutter<byte[]>
    {
        public byte[] Message { get; private set; }

        public event EventHandler OnMessageCut;
        public event EventHandler<MessageCutterInvalidMessageReadEventArg> OnInvalidMessageRead;
        private readonly List<byte> buffer = new List<byte>();

        /// <summary>
        /// 
        /// </summary>
        public void Feed(byte[] next)
        {
            for (int i = 0; i < next.Length; i++)
            {
                this.buffer.Add(next[i]);

                if (this.buffer[0] != 0xFA)
                {
                    this.OnInvalidMessageRead?.Invoke(this,
                        new MessageCutterInvalidMessageReadEventArg()
                        {
                            Message =
                                "invalid byte[0]: 0x"
                                    + this.buffer[0].ToString("x2")
                                    + " clear buf and continue reading..."
                        });
                    this.buffer.Clear();
                    continue;
                }

                //根据协议文档，该数从0x01递增到0x3F,然后再回到0x00,继续递增循环。
                //注意注意，实际加油机会发送0x40进来，可能是油机的BUG，所以这里放开到0x40
                if (this.buffer.Count >= 4
                    && (this.buffer[3] == 0 || this.buffer[3] > 0x40))
                {
                    this.OnInvalidMessageRead?.Invoke(this,
                        new MessageCutterInvalidMessageReadEventArg()
                        {
                            Message =
                                "invalid byte[3] of FrameNo.: 0x"
                                    + this.buffer[3].ToString("x2")
                                    + " clear buf and continue reading..."
                        });
                    this.buffer.Clear();
                    continue;
                }

                if (this.buffer.Count >= 5 &&
                   this.buffer.Count == (this.buffer[4] + 6))
                {
                    this.Message = this.buffer.ToArray();
                    var safe = this.OnMessageCut;
                    safe?.Invoke(this, null);
                    this.buffer.Clear();
                }

                if (this.buffer.Count >= 300)
                {
                    this.OnInvalidMessageRead?.Invoke(this,
                        new MessageCutterInvalidMessageReadEventArg()
                        {
                            Message = "Long length(len: " + this.buffer.Count + ") message is still constructing in MsgCutter: 0x" + this.buffer.ToHexLogString()
                        });
                    this.buffer.Clear();
                    continue;
                }
            }
        }
    }
}