/// <summary>
/// To build the byte array which represents this Gaia Packet over BLE.
/// The bytes array is built according to the definition of a GAIA Packet sent over BLE:
/// 0 bytes 1 2 3 4 len+4
/// +--------+---------+--------+--------+ +--------+--------+
/// | VENDOR ID | COMMAND ID | | PAYLOAD ... |
/// +--------+---------+--------+--------+ +--------+--------+
/// </summary>
/// <param name="_commandId">The command ID for the packet bytes to build:
/// The original command ID of this packet.
/// The acknowledgement version of the original command ID.</param>
/// <param name="_payload">The payload to include in the packet bytes.</param>
/// <returns>A new byte array built with the given information.</returns>
public override byte[] BuildBytes(int _commandId, byte[] _payload)
{
int length = _payload.Length + OFFSET_PAYLOAD;
byte[] data = new byte[length];
try
{
GaiaUtils.CopyIntIntoByteArray(VendorId, data, OFFSET_VENDOR_ID, LENGTH_VENDOR_ID, false);
GaiaUtils.CopyIntIntoByteArray(_commandId, data, OFFSET_COMMAND_ID, LENGTH_COMMAND_ID, false);
Array.Copy(_payload, 0, data, OFFSET_PAYLOAD, _payload.Length);
}
catch (GaiaException)
{
throw new GaiaException(GaiaException.Type.PAYLOAD_LENGTH_TOO_LONG);
}
return(data);
}
/// <summary>
/// To build the byte array which represents this Gaia Packet over BR/EDR.
/// The bytes array is built according to the definition of a GAIA Packet sent over BR/EDR:
/// 0 bytes 1 2 3 4 5 6 7 8 9 len+8
/// +--------+---------+--------+--------+--------+--------+--------+--------+ +--------+--------+ +--------+
/// | SOF | VERSION | FLAGS | LENGTH | VENDOR ID | COMMAND ID | | PAYLOAD ... | | CHECK |
/// +--------+---------+--------+--------+--------+--------+--------+--------+ +--------+--------+ +--------+
/// </summary>
/// <param name="_commandId">The command ID for the packet bytes to build:
/// The original command ID of this packet.
/// The acknowledgement version of the original command ID.</param>
/// <param name="_payload">The payload to include in the packet bytes.</param>
/// <returns>A new byte array built with the given information.</returns>
public override byte[] BuildBytes(int _commandId, byte[] _payload)
{
// if the payload is bigger than the maximum size: packet won't be sent.
if (_payload.Length > MAX_PAYLOAD)
{
throw new GaiaException(GaiaException.Type.PAYLOAD_LENGTH_TOO_LONG);
}
int length = _payload.Length + OFFSET_PAYLOAD + (mHasChecksum ? CHECK_LENGTH : 0);
byte[] data = new byte[length];
data[OFFSET_SOF] = SOF;
data[OFFSET_VERSION] = (byte)PROTOCOL_VERSION;
data[OFFSET_FLAGS] = 0x01;
if (!mHasChecksum)
{
data[OFFSET_FLAGS] = 0x00;
}
data[OFFSET_LENGTH] = (byte)Payload.Length;
GaiaUtils.CopyIntIntoByteArray(VendorId, data, OFFSET_VENDOR_ID, LENGTH_VENDOR_ID, false);
GaiaUtils.CopyIntIntoByteArray(_commandId, data, OFFSET_COMMAND_ID, LENGTH_COMMAND_ID, false);
Array.Copy(_payload, 0, data, OFFSET_PAYLOAD, _payload.Length);
// if there is a checksum, calculating the checksum value
if (mHasChecksum)
{
byte check = 0;
for (int i = 0; i < length - 1; i++)
{
check ^= data[i];
}
data[length - 1] = check;
}
return(data);
}
