1from fontTools.misc.textTools import bytesjoin, tobytes, safeEval 2from . import DefaultTable 3import struct 4 5# https://developer.apple.com/fonts/TrueType-Reference-Manual/RM06/Chap6ltag.html 6 7 8class table__l_t_a_g(DefaultTable.DefaultTable): 9 def __init__(self, tag=None): 10 DefaultTable.DefaultTable.__init__(self, tag) 11 self.version, self.flags = 1, 0 12 self.tags = [] 13 14 def addTag(self, tag): 15 """Add 'tag' to the list of langauge tags if not already there. 16 17 Returns the integer index of 'tag' in the list of all tags. 18 """ 19 try: 20 return self.tags.index(tag) 21 except ValueError: 22 self.tags.append(tag) 23 return len(self.tags) - 1 24 25 def decompile(self, data, ttFont): 26 self.version, self.flags, numTags = struct.unpack(">LLL", data[:12]) 27 assert self.version == 1 28 self.tags = [] 29 for i in range(numTags): 30 pos = 12 + i * 4 31 offset, length = struct.unpack(">HH", data[pos : pos + 4]) 32 tag = data[offset : offset + length].decode("ascii") 33 self.tags.append(tag) 34 35 def compile(self, ttFont): 36 dataList = [struct.pack(">LLL", self.version, self.flags, len(self.tags))] 37 stringPool = "" 38 for tag in self.tags: 39 offset = stringPool.find(tag) 40 if offset < 0: 41 offset = len(stringPool) 42 stringPool = stringPool + tag 43 offset = offset + 12 + len(self.tags) * 4 44 dataList.append(struct.pack(">HH", offset, len(tag))) 45 dataList.append(tobytes(stringPool)) 46 return bytesjoin(dataList) 47 48 def toXML(self, writer, ttFont): 49 writer.simpletag("version", value=self.version) 50 writer.newline() 51 writer.simpletag("flags", value=self.flags) 52 writer.newline() 53 for tag in self.tags: 54 writer.simpletag("LanguageTag", tag=tag) 55 writer.newline() 56 57 def fromXML(self, name, attrs, content, ttFont): 58 if not hasattr(self, "tags"): 59 self.tags = [] 60 if name == "LanguageTag": 61 self.tags.append(attrs["tag"]) 62 elif "value" in attrs: 63 value = safeEval(attrs["value"]) 64 setattr(self, name, value) 65