mcimport/nbt.py

59 lines
1.8 KiB
Python

import struct
def _read_tag(bytes, index, tag):
if tag <= 6:
plen = (None, 1, 2, 4, 8, 4, 8)[tag]
value = struct.unpack(">"+(None, "b", "h", "i", "q", "f", "d")[tag],
bytes[index:index+plen])[0]
index += plen
return value, index
elif tag == 7:
plen, index = _read_tag(bytes, index, 3)
value = list(struct.unpack(">"+str(plen)+"B", bytes[index:index+plen]))
index += plen
return value, index
elif tag == 11:
plen, index = _read_tag(bytes, index, 3)
value = list(struct.unpack(">"+str(plen)+"i", bytes[index:index+4*plen]))
index += 4*plen
return value, index
elif tag == 12:
plen, index = _read_tag(bytes, index, 3)
value = list(struct.unpack(">"+str(plen)+"q", bytes[index:index+8*plen]))
index += 8*plen
return value, index
elif tag == 8:
plen, index = _read_tag(bytes, index, 2)
value = bytes[index:index+plen].decode('utf-8')
index += plen
return value, index
elif tag == 9:
tagid = bytes[index]
index += 1
plen, index = _read_tag(bytes, index, 3)
value = []
for i in range(plen):
v, index = _read_tag(bytes, index, tagid)
value.append(v)
return value, index
elif tag == 10:
return _read_named(bytes, index)
else:
raise Exception("Unknown tag: " + str(tag))
def _read_named(bytes, index):
d = {}
while True:
if index >= len(bytes):
return d, index
tag = bytes[index]
index += 1
if tag == 0:
return d, index
name, index = _read_tag(bytes, index, 8)
value, index = _read_tag(bytes, index, tag)
d[name] = value
def read(bytes):
return _read_named(bytes, 0)[0]