public DecodedLoraPacket DecodeMessage(string encodedPhysicalPayload)
{
// conver to hex
var byteArray = Convert.FromBase64String(encodedPhysicalPayload);
var hexValuesList = BitConverter.ToString(byteArray).Split("-").ToList();
// create packet
DecodedLoraPacket decodedPacket = new DecodedLoraPacket()
{
OriginalHexString = string.Join("", hexValuesList)
};
var physicalPayload = new PhysicalPayload
{
MacHeader = hexValuesList[0],
MIC = string.Join("", hexValuesList).Substring((hexValuesList.Count * 2) - 8, 8)
};
hexValuesList.RemoveRange(hexValuesList.Count - 4, 4);
hexValuesList.RemoveAt(0);
var frameHeader = new FrameHeader
{
DeviceAddress = hexValuesList[3] + hexValuesList[2] + hexValuesList[1] + hexValuesList[0], // big endian
FrameControlOctet = hexValuesList[4],
FrameCounter = hexValuesList[6] + hexValuesList[5] // big endian
};
// frame options is optional, need to work out size / if its present using octet
var binaryFrameControl = Convert.ToString(Convert.ToInt32(frameHeader.FrameControlOctet, 16), 2);
var frameOptionsOffset = Convert.ToInt32(binaryFrameControl.Substring(binaryFrameControl.Length - 3, 3));
if (frameOptionsOffset != 0)
{
for (int i = 1; i <= frameOptionsOffset; i++)
{
frameHeader.FrameOptions += hexValuesList[6 + i];
}
}
// FramePayload
var values = string.Join("", hexValuesList);
var payloadOffset = 16 + (frameOptionsOffset * 2);
var macPayload = new MacPayload
{
FramePort = hexValuesList[7 + frameOptionsOffset],
FramePayload = values.Substring(payloadOffset, values.Length - payloadOffset),
FrameHeader = frameHeader
};
// combine structures
physicalPayload.MacPayload = macPayload;
decodedPacket.PhysicalPayload = physicalPayload;
return(decodedPacket);
}
public string ToVerboseString()
{
StringBuilder sb = new StringBuilder();
sb.AppendFormat("Message Type = {0}", Mhdr.MessageType).AppendLine();
sb.AppendFormat(" PHYPayload = {0}", Packet.ToHexString()).AppendLine();
sb.AppendLine();
sb.AppendFormat(" (PHYPayload = MHDR[1] | MACPayload[..] | MIC[4])").AppendLine();
sb.AppendFormat(" MHDR = {0}", Mhdr.RawData.ToHexString()).AppendLine();
sb.AppendFormat(" MACPayload = {0}", MacPayload.RawData.ToHexString()).AppendLine();
sb.AppendFormat(" MIC = {0}", Mic.RawData.ToHexString()).AppendLine();
sb.AppendLine();
sb.Append(MacPayload.ToVerboseString());
return(sb.ToString());
}
