/// <summary>
/// Deserialize a stream of bytes into a message.<br />Use with caution.
/// </summary>
public static Message Deserialize(MemoryStream memoryStream)
{
// if `leaveOpen` is left false, this will dispose the memory stream once the BitEncodedStreamReader is disposed.
// we don't want to dispose the memory stream because we continually reuse it for reading
var rawBufferData = memoryStream.GetBufferWithReflection().Span;
var stream = new BitEncodedSpanReader(rawBufferData);
var scope = (ConnectionScope)stream.ReadByte();
var type = (MessageType)stream.Read7BitEncodedInt();
// i have chosen to initialize the list to this mathemetical number,
// because i don't want it to go from 4 -> 16 -> 64 ...
// and would rather have it start at like 123 if the length is 32 * 123
var argData = new List <object>(rawBufferData.Length / 32);
while (stream.Position < rawBufferData.Length)
{
var patternType = stream.ReadByte();
// it is very common for there to be empty blocks in a world
// this is a minor optimization which will try to excersize that
while (patternType == _patternBooleanFalse)
{
argData.Add(false);
if (stream.Position >= rawBufferData.Length)
{
goto EndOfFunction;
}
patternType = stream.ReadByte();
}
switch (patternType)
{
// we can guarantee that this is not possible, because
// we ruled it out with the optimization above
// case _patternBooleanFalse: argData.Add(false); break;
case _patternIntPos: argData.Add(stream.Read7BitEncodedInt()); break;
case _patternString: argData.Add(stream.ReadString()); break;
case _patternIntNeg: argData.Add(-stream.Read7BitEncodedInt() - 1); break;
case _patternBooleanTrue: argData.Add(true); break;
case _patternDouble: argData.Add(BitConverter.ToDouble(stream.ReadBytes(8))); break;
case _patternBytes:
{
var length = stream.Read7BitEncodedInt();
argData.Add(stream.ReadBytes(length).ToArray());
}
break;
case _patternObject:
{
var objectArgs = new MessageObject();
while (stream.ReadByte() != _patternObjectEnd)
{
stream.Position--;
object value;
switch (stream.ReadByte())
{
case _patternString: value = stream.ReadString(); break;
case _patternIntPos: value = stream.Read7BitEncodedInt(); break;
case _patternIntNeg: value = -stream.Read7BitEncodedInt() - 1; break;
case _patternDouble: value = BitConverter.ToDouble(stream.ReadBytes(8)); break;
case _patternBooleanFalse: value = false; break;
case _patternBooleanTrue: value = true; break;
case _patternBytes:
{
var length = stream.Read7BitEncodedInt();
value = stream.ReadBytes(length).ToArray();
}
break;
default: throw new InvalidDataException($"Invalid pattern type {patternType} in MessageObject.");
}
objectArgs.Add(stream.ReadString(), value);
}
argData.Add(objectArgs);
}
break;
default: throw new InvalidDataException($"Invalid pattern type {patternType}.");
}
}
EndOfFunction:
return(new Message(scope, type, argData.ToArray()));
}