package base

    [Serializable]
    public abstract class PacketBase {
        protected PacketHead packetHead;
        protected PacketPayload packetPayload;

        public PacketBase(PacketHead packetHead, PacketPayload packetPayload) {
            this.packetHead = packetHead;
            this.packetPayload = packetPayload;
            if(packetPayload != null) {
                this.packetHead.PayloadLength = packetPayload.RawData.Length;
            }
        }

        public PacketBase() {
            this.packetHead = new PacketHead();
            this.packetPayload = new PacketPayload();
        }

        /// <summary>
        /// 与Packet对应的二进制数据报
        /// </summary>
        public byte[] ByteArray {
            get {
                byte[] buf = null;
                if(packetPayload != null) {
                    buf = new byte[packetHead.RawData.Length + packetPayload.RawData.Length];
                    Array.Copy(packetHead.RawData, buf, packetHead.RawData.Length);
                    Array.Copy(packetPayload.RawData, 0, buf, packetHead.RawData.Length, packetPayload.RawData.Length);
                } else {
                    buf = new byte[packetHead.RawData.Length];
                    Array.Copy(packetHead.RawData, buf, packetHead.RawData.Length);
                }
                return buf;
            }
            set {
                if(value.Length >= PacketHead.HeadLength) {
                    byte[] buf = new byte[PacketHead.HeadLength];
                    Array.Copy(value, buf, PacketHead.HeadLength);
                    packetHead = new PacketHead(buf);
                    int nPayload = value.Length - PacketHead.HeadLength;
                    if(nPayload > 0) {
                        buf = new byte[nPayload];
                        Array.Copy(value, PacketHead.HeadLength, buf, 0, nPayload);
                        packetPayload = new PacketPayload(buf);
                    } else {
                        packetPayload = null;
                    }
                } else {
                    throw new Exception(Properties.Resources.DataLengthError);
                }
            }
        }

        #region 公开Packet头部的属性
        public PacketType PacketType {
            get {
                return packetHead.PacketType;
            }
        }

        public IPAddress SourceIp {
            get {
                return packetHead.SourceIp;
            }
            set {
                packetHead.SourceIp = value;
            }
        }

        public IPAddress DestIp {
            get {
                return packetHead.DestIp;
            }
            set {
                packetHead.DestIp = value;
            }
        }

        public int PktId {
            get {
                return packetHead.PktId;
            }
            set {
                packetHead.PktId = value;
            }
        }

        public int PayloadLength {
            get {
                return packetHead.PayloadLength;
            }
            set {
                packetHead.PayloadLength = value;
            }
        }
        #endregion
    }