private void readFunctions(List<LuaConstant> constants, DataSource source) throws IOException {
while (source.getUByte() == '#') {
int idx = source.getUShort();
LuaFunction func = readFunction(source);
constants.set(idx, new LuaConstant<>(func));
}
}
private ArrayList<LocalVarDefinition> readLocals(DataSource source) throws IOException {
int count = source.getUShort();
ArrayList<LocalVarDefinition> lvars = new ArrayList<>();
for (int i = 0; i < count; i++)
lvars.add(new LocalVarDefinition(source.getUShort(), readTString(source)));
lvars.add(new LocalVarDefinition(-1, null));
return lvars;
}
private String readTString(DataSource source) throws IOException {
int size = source.getUShort();
if (size == 0) return null;
byte[] b = new byte[size];
source.get(b, 0, size);
for (int i = 0; i < b.length; i++) b[i] ^= 0xff;
String s = new String(b);
if (s.endsWith("\0")) s = s.substring(0, s.length() - 1);
return s;
}
private LuaFunction readFunction(DataSource source) throws IOException {
LuaFunction lf = new LuaFunction();
lf.lineNo = source.getUShort();
lf.source = readTString(source);
int codeSize = source.getInt();
lf.code = new byte[codeSize];
source.get(lf.code);
lf.constants = readConstants(source);
lf.localVars = readLocals(source);
readFunctions(lf.constants, source);
return lf;
}
@Override
protected LuaChunk _read(DataSource source) throws IOException {
int magic = source.getInt();
if (magic != 0x1B4C7561) throw new IOException("Invalid LUA file");
int version = source.getUByte();
if (version != 0x31)
throw new IOException("Invalid LUA file version: " + Integer.toHexString(version));
if (source.getUByte() != 4) throw new IOException("Invalid LUA file, float length isn't 4...");
source.skip(4); // Todo: wtf are these?
LuaFunction lf = readFunction(source);
// Todo: decompile? haha, if it'll be anything like the java decompiler I wrote then f**k that
return new LuaChunk(source.container, source.getName(), lf);
}
private ArrayList<LuaConstant> readConstants(DataSource source) throws IOException {
int count = source.getUShort();
ArrayList<LuaConstant> constants = new ArrayList<>(count);
for (int i = 0; i < count; i++) {
int type = source.getUByte();
switch (type) {
case 'N': // number, float - 4 bytes
constants.add(new LuaConstant<>(source.getFloatLE()));
break;
case 'S': // string
constants.add(new LuaConstant<>(readTString(source)));
break;
case 'F': // constant function, for some reason it uses null here :S
// (https://github.com/residualvm/residualvm/blob/master/engines/grim/lua/lundump.cpp#L112)
constants.add(new LuaConstant<LuaFunction>(null));
break;
default:
System.err.println("Unknown LUA constant type: " + ((char) type));
break;
}
}
return constants;
}
