public bool TryGetDecimal(Guid publicId, out decimal id)
{
Span <byte> idBytes = stackalloc byte[16];
var decimals = MemoryMarshal.Cast <byte, decimal>(idBytes);
var decimalComponents = MemoryMarshal.Cast <byte, int>(idBytes);
// Invalid input if sign-and-scale component (4 bytes) are non-zero or max value is exceeded
if (!TryGetIdBytes(publicId, idBytes) || DecimalStructure.GetSignAndScale(decimalComponents) != 0 || (id = decimals[0]) > DistributedIdGenerator.MaxValue)
{
id = default;
return(false);
}
return(true);
}
private static Guid Guid(decimal value)
{
var decimals = MemoryMarshal.CreateSpan(ref value, length: 1);
var components = MemoryMarshal.Cast <decimal, int>(decimals);
var lo = DecimalStructure.GetLo(components);
var mid = DecimalStructure.GetMid(components);
var hi = (uint)DecimalStructure.GetHi(components);
var signAndScale = DecimalStructure.GetSignAndScale(components);
Span <byte> bytes = stackalloc byte[16];
BinaryPrimitives.TryWriteInt32LittleEndian(bytes, 0);
BinaryPrimitives.TryWriteUInt16LittleEndian(bytes[4..], (ushort)(hi >> 16));
/// <summary>
/// Validates that the given ID is valid, and returns its components.
/// </summary>
private static (int SignAndScale, int Hi, int Mid, int Lo) ExtractAndValidateIdComponents(decimal id)
{
if (id < 0m)
{
throw new ArgumentOutOfRangeException();
}
// Extract the components
var decimals = MemoryMarshal.CreateReadOnlySpan(ref id, length: 1);
var components = MemoryMarshal.Cast <decimal, int>(decimals);
var signAndScale = DecimalStructure.GetSignAndScale(components);
var hi = DecimalStructure.GetHi(components);
var lo = DecimalStructure.GetLo(components);
var mid = DecimalStructure.GetMid(components);
// Validate format and range
if (id > DistributedIdGenerator.MaxValue || signAndScale != 0)
{
throw new ArgumentException($"The ID must be positive, have no decimal places, and consist of no more than 28 digits.", nameof(id));
}
return(signAndScale, hi, mid, lo);
}
static AesPublicIdentityConverter()
{
// Ensure that decimals are still structured the same way
// This prevents the application from ever generating incorrect public identities in this extremely unlikely scenario, allowing a fix to be created
DecimalStructure.ThrowIfDecimalStructureIsUnexpected();
}
