Formats::Chiptune::Container::Ptr Parse(const Binary::Container& data, Builder& target)
{
if (!FastCheck(data))
{
return Formats::Chiptune::Container::Ptr();
}
try
{
Binary::InputStream stream(data);
stream.ReadField<SignatureType>();
target.SetTitle(DecodeString(stream.ReadCString(MAX_STRING_SIZE)));
target.SetAuthor(DecodeString(stream.ReadCString(MAX_STRING_SIZE)));
target.SetComment(DecodeString(stream.ReadCString(MAX_COMMENT_SIZE)));
const std::size_t fixedOffset = stream.GetPosition();
std::size_t totalFrames = 0;
for (;;)
{
const uint8_t val = stream.ReadField<uint8_t>();
if (val == FINISH)
{
break;
}
switch (val)
{
case BEGIN_FRAME:
++totalFrames;
target.BeginFrames(1);
break;
case SKIP_FRAMES:
{
const uint_t frames = 3 + stream.ReadField<uint8_t>();
totalFrames += frames;
target.BeginFrames(frames);
}
break;
case SELECT_SECOND_CHIP:
target.SelectChip(1);
break;
case SELECT_FIRST_CHIP:
target.SelectChip(0);
break;
case LOOP_MARKER:
target.SetLoop();
break;
default:
target.SetRegister(val, stream.ReadField<uint8_t>());
break;
}
}
Require(totalFrames >= MIN_FRAMES);
const std::size_t usedSize = stream.GetPosition();
const auto subData = stream.GetReadData();
return CreateCalculatingCrcContainer(subData, fixedOffset, usedSize - fixedOffset);
}
catch (const std::exception&)
{
return Formats::Chiptune::Container::Ptr();
}
}
