public static void ChangeDemoDir(SourceDemo demo, Stream s, string newDir)
{
void Write(byte[] buf) => s.Write(buf, 0, buf.Length);
string old = demo.Header.GameDirectory;
if (old == newDir)
{
// no difference
Write(demo.Reader.Data);
return;
}
int lenDiff = newDir.Length - old.Length;
BitStreamReader bsr = demo.Reader;
byte[] dirBytes = Encoding.ASCII.GetBytes(newDir);
Write(bsr.ReadBytes(796));
Write(dirBytes); // header doesn't matter but I change it anyway
Write(new byte[260 - newDir.Length]);
bsr.SkipBytes(260);
Write(bsr.ReadBytes(12));
byte[] tmp = BitConverter.GetBytes((uint)(bsr.ReadUInt() + lenDiff));
if (!BitConverter.IsLittleEndian)
{
tmp = tmp.Reverse().ToArray();
}
Write(tmp);
foreach (SignOn signOn in demo.FilterForPacket <SignOn>().Where(signOn => signOn.FilterForMessage <SvcServerInfo>().Any()))
{
// catch up to signOn packet
int byteCount = (signOn.Reader.AbsoluteBitIndex - bsr.AbsoluteBitIndex) / 8;
Write(bsr.ReadBytes(byteCount));
bsr.SkipBits(signOn.Reader.BitLength);
BitStreamWriter bsw = new BitStreamWriter();
BitStreamReader signOnReader = signOn.Reader;
bsw.WriteBits(signOnReader.ReadRemainingBits());
signOnReader = signOnReader.FromBeginning();
int bytesToMessageStreamSize = demo.DemoInfo.MaxSplitscreenPlayers * 76 + 8;
signOnReader.SkipBytes(bytesToMessageStreamSize);
// edit the message stream length - read uint, and edit at index before the reading of said uint
bsw.EditIntAtIndex((int)(signOnReader.ReadUInt() + lenDiff), signOnReader.CurrentBitIndex - 32, 32);
// actually change the game dir
SvcServerInfo serverInfo = signOn.FilterForMessage <SvcServerInfo>().Single();
int editIndex = serverInfo.GameDirBitIndex - signOn.Reader.AbsoluteBitIndex;
bsw.RemoveBitsAtIndex(editIndex, old.Length * 8);
bsw.InsertBitsAtIndex(dirBytes, editIndex, newDir.Length * 8);
Write(bsw.AsArray);
}
Write(bsr.ReadRemainingBits().bytes);
}
// writes a edited version of the given demo to the stream
// this is all manually hacked together and it shall stay this way for now
public static void RemoveCaptions(SourceDemo demo, Stream s)
{
void Write(byte[] buf) => s.Write(buf, 0, buf.Length);
Packet[] closeCaptionPackets = demo.FilterForPacket <Packet>()
.Where(packet => packet.FilterForMessage <SvcUserMessage>()
.Any(frame => frame.MessageType == UserMessageType.CloseCaption)).ToArray();
if (closeCaptionPackets.Length == 0)
{
Write(demo.Reader.Data);
return;
}
int changedPackets = 0;
Write(demo.Header.Reader.ReadRemainingBits().bytes);
foreach (PacketFrame frame in demo.Frames)
{
if (frame.Packet != closeCaptionPackets[changedPackets])
{
Write(frame.Reader.ReadRemainingBits().bytes); // write frames that aren't changed
}
else
{
Packet p = (Packet)frame.Packet;
BitStreamWriter bsw = new BitStreamWriter(frame.Reader.BitLength / 8);
var last = p.MessageStream.Last().message;
int len = last.Reader.AbsoluteStart - frame.Reader.AbsoluteStart + last.Reader.BitLength;
bsw.WriteBits(frame.Reader.ReadBits(len), len);
int msgSizeOffset = p.MessageStream.Reader.AbsoluteStart - frame.Reader.AbsoluteStart;
int typeInfoLen = demo.DemoInfo.NetMsgTypeBits + demo.DemoInfo.UserMessageLengthBits + 8;
bsw.RemoveBitsAtIndices(p.FilterForUserMessage <CloseCaption>()
.Select(caption => (caption.Reader.AbsoluteStart - frame.Reader.AbsoluteStart - typeInfoLen,
caption.Reader.BitLength + typeInfoLen)));
bsw.WriteUntilByteBoundary();
bsw.EditIntAtIndex((bsw.BitLength - msgSizeOffset - 32) >> 3, msgSizeOffset, 32);
Write(bsw.AsArray);
// if we've edited all the packets, write the rest of the data in the demo
if (++changedPackets == closeCaptionPackets.Length)
{
BitStreamReader tmp = demo.Reader;
tmp.SkipBits(frame.Reader.AbsoluteStart + frame.Reader.BitLength);
Write(tmp.ReadRemainingBits().bytes);
break;
}
}
}
}