/// <summary>
/// Get correct bytes according to a given <see cref="Endianness"/>
/// </summary>
/// <param name="shorts">Array of <see cref="ushort">shorts</see></param>
/// <param name="endianness"><see cref="Endianness"/> expected in the shorts</param>
/// <returns>Array of <see cref="byte"/> with correct endian for current CPU</returns>
public static byte[] GetBytes(this ushort[] shorts, Endianness endianness)
{
ushort[] targetShorts = new ushort[shorts.Length];
Array.Copy(shorts, targetShorts, shorts.Length);
if (endianness.ShouldSwapWords())
{
Array.Reverse(targetShorts);
}
var bytes = new byte[targetShorts.Length * 2];
var byteIndex = 0;
for (var i = 0; i < targetShorts.Length; i++)
{
var resultBytes = BitConverter.GetBytes(targetShorts[i]);
if (endianness.ShouldSwapBytes())
{
Array.Reverse(resultBytes);
}
Array.Copy(resultBytes, 0, bytes, byteIndex, resultBytes.Length);
byteIndex += resultBytes.Length;
}
return(bytes);
}
/// <summary>
/// Extension function to get the bytes of the payload, with corrected endianness.
/// </summary>
/// <param name="shorts">the collection of shorts to get the individual bytes from</param>
/// <param name="endianness">the endianness to use</param>
/// <param name="dataType">the Modbus data type</param>
/// <returns>a collection of endianness corrected bytes</returns>
public static IEnumerable <byte> GetBytes(this IEnumerable <ushort> shorts, Endianness endianness, DataType dataType)
{
var shortsInDataPoint = dataType switch
{
DataType.Float or DataType.Int32 or DataType.Uint32 => 2,
_ => 1
};
var bytesInDataPoint = shortsInDataPoint * 2;
var numBytes = shorts.Count() * 2;
if (numBytes % bytesInDataPoint != 0)
{
throw new ElementsNotPerfectlyDivisableIntoChunksException(numBytes, bytesInDataPoint);
}
shorts = (endianness.ShouldSwapWords()) ? shorts.ChunkwiseReverse(shortsInDataPoint) : shorts;
var bytes = shorts.SelectMany(sh => BitConverter.GetBytes(sh)).ToList();
bytes = (endianness.ShouldSwapBytesInWords()) ? bytes.ChunkwiseReverse(2).ToList() : bytes;
return(bytes);
}
