xref: /external/fonttools/Tools/fontTools/misc/psLib.py

from __future__ import print_function, division, absolute_import
from fontTools.misc.py23 import *
from fontTools.misc import eexec
from .psOperators import *
import re
import collections
from string import whitespace


ps_special = '()<>[]{}%'	# / is one too, but we take care of that one differently

skipwhiteRE = re.compile("[%s]*" % whitespace)
endofthingPat = "[^][(){}<>/%%%s]*" % whitespace
endofthingRE = re.compile(endofthingPat)
commentRE = re.compile("%[^\n\r]*")

# XXX This not entirely correct as it doesn't allow *nested* embedded parens:
stringPat = r"""
	\(
		(
			(
				[^()]*   \   [()]
			)
			|
			(
				[^()]*  \(   [^()]*  \)
			)
		)*
		[^()]*
	\)
"""
stringPat = "".join(stringPat.split())
stringRE = re.compile(stringPat)

hexstringRE = re.compile("<[%s0-9A-Fa-f]*>" % whitespace)

class PSTokenError(Exception): pass
class PSError(Exception): pass


class PSTokenizer(StringIO):

	def getnexttoken(self,
			# localize some stuff, for performance
			len=len,
			ps_special=ps_special,
			stringmatch=stringRE.match,
			hexstringmatch=hexstringRE.match,
			commentmatch=commentRE.match,
			endmatch=endofthingRE.match,
			whitematch=skipwhiteRE.match):

		_, nextpos = whitematch(self.buf, self.pos).span()
		self.pos = nextpos
		if self.pos >= self.len:
			return None, None
		pos = self.pos
		buf = self.buf
		char = buf[pos]
		if char in ps_special:
			if char in '{}[]':
				tokentype = 'do_special'
				token = char
			elif char == '%':
				tokentype = 'do_comment'
				_, nextpos = commentmatch(buf, pos).span()
				token = buf[pos:nextpos]
			elif char == '(':
				tokentype = 'do_string'
				m = stringmatch(buf, pos)
				if m is None:
					raise PSTokenError('bad string at character %d' % pos)
				_, nextpos = m.span()
				token = buf[pos:nextpos]
			elif char == '<':
				tokentype = 'do_hexstring'
				m = hexstringmatch(buf, pos)
				if m is None:
					raise PSTokenError('bad hexstring at character %d' % pos)
				_, nextpos = m.span()
				token = buf[pos:nextpos]
			else:
				raise PSTokenError('bad token at character %d' % pos)
		else:
			if char == '/':
				tokentype = 'do_literal'
				m = endmatch(buf, pos+1)
			else:
				tokentype = ''
				m = endmatch(buf, pos)
			if m is None:
				raise PSTokenError('bad token at character %d' % pos)
			_, nextpos = m.span()
			token = buf[pos:nextpos]
		self.pos = pos + len(token)
		return tokentype, token

	def skipwhite(self, whitematch=skipwhiteRE.match):
		_, nextpos = whitematch(self.buf, self.pos).span()
		self.pos = nextpos

	def starteexec(self):
		self.pos = self.pos + 1
		#self.skipwhite()
		self.dirtybuf = self.buf[self.pos:]
		self.buf, R = eexec.decrypt(self.dirtybuf, 55665)
		self.len = len(self.buf)
		self.pos = 4

	def stopeexec(self):
		if not hasattr(self, 'dirtybuf'):
			return
		self.buf = self.dirtybuf
		del self.dirtybuf

	def flush(self):
		if self.buflist:
			self.buf = self.buf + "".join(self.buflist)
			self.buflist = []


class PSInterpreter(PSOperators):

	def __init__(self):
		systemdict = {}
		userdict = {}
		self.dictstack = [systemdict, userdict]
		self.stack = []
		self.proclevel = 0
		self.procmark = ps_procmark()
		self.fillsystemdict()

	def fillsystemdict(self):
		systemdict = self.dictstack[0]
		systemdict['['] = systemdict['mark'] = self.mark = ps_mark()
		systemdict[']'] = ps_operator(']', self.do_makearray)
		systemdict['true'] = ps_boolean(1)
		systemdict['false'] = ps_boolean(0)
		systemdict['StandardEncoding'] = ps_array(ps_StandardEncoding)
		systemdict['FontDirectory'] = ps_dict({})
		self.suckoperators(systemdict, self.__class__)

	def suckoperators(self, systemdict, klass):
		for name in dir(klass):
			attr = getattr(self, name)
			if isinstance(attr, collections.Callable) and name[:3] == 'ps_':
				name = name[3:]
				systemdict[name] = ps_operator(name, attr)
		for baseclass in klass.__bases__:
			self.suckoperators(systemdict, baseclass)

	def interpret(self, data, getattr = getattr):
		tokenizer = self.tokenizer = PSTokenizer(data)
		getnexttoken = tokenizer.getnexttoken
		do_token = self.do_token
		handle_object = self.handle_object
		try:
			while 1:
				tokentype, token = getnexttoken()
				#print token
				if not token:
					break
				if tokentype:
					handler = getattr(self, tokentype)
					object = handler(token)
				else:
					object = do_token(token)
				if object is not None:
					handle_object(object)
			tokenizer.close()
			self.tokenizer = None
		finally:
			if self.tokenizer is not None:
				if 0:
					print('ps error:\n- - - - - - -')
					print(self.tokenizer.buf[self.tokenizer.pos-50:self.tokenizer.pos])
					print('>>>')
					print(self.tokenizer.buf[self.tokenizer.pos:self.tokenizer.pos+50])
					print('- - - - - - -')

	def handle_object(self, object):
		if not (self.proclevel or object.literal or object.type == 'proceduretype'):
			if object.type != 'operatortype':
				object = self.resolve_name(object.value)
			if object.literal:
				self.push(object)
			else:
				if object.type == 'proceduretype':
					self.call_procedure(object)
				else:
					object.function()
		else:
			self.push(object)

	def call_procedure(self, proc):
		handle_object = self.handle_object
		for item in proc.value:
			handle_object(item)

	def resolve_name(self, name):
		dictstack = self.dictstack
		for i in range(len(dictstack)-1, -1, -1):
			if name in dictstack[i]:
				return dictstack[i][name]
		raise PSError('name error: ' + str(name))

	def do_token(self, token,
				int=int,
				float=float,
				ps_name=ps_name,
				ps_integer=ps_integer,
				ps_real=ps_real):
		try:
			num = int(token)
		except (ValueError, OverflowError):
			try:
				num = float(token)
			except (ValueError, OverflowError):
				if '#' in token:
					hashpos = token.find('#')
					try:
						base = int(token[:hashpos])
						num = int(token[hashpos+1:], base)
					except (ValueError, OverflowError):
						return ps_name(token)
					else:
						return ps_integer(num)
				else:
					return ps_name(token)
			else:
				return ps_real(num)
		else:
			return ps_integer(num)

	def do_comment(self, token):
		pass

	def do_literal(self, token):
		return ps_literal(token[1:])

	def do_string(self, token):
		return ps_string(token[1:-1])

	def do_hexstring(self, token):
		hexStr = "".join(token[1:-1].split())
		if len(hexStr) % 2:
			hexStr = hexStr + '0'
		cleanstr = []
		for i in range(0, len(hexStr), 2):
			cleanstr.append(chr(int(hexStr[i:i+2], 16)))
		cleanstr = "".join(cleanstr)
		return ps_string(cleanstr)

	def do_special(self, token):
		if token == '{':
			self.proclevel = self.proclevel + 1
			return self.procmark
		elif token == '}':
			proc = []
			while 1:
				topobject = self.pop()
				if topobject == self.procmark:
					break
				proc.append(topobject)
			self.proclevel = self.proclevel - 1
			proc.reverse()
			return ps_procedure(proc)
		elif token == '[':
			return self.mark
		elif token == ']':
			return ps_name(']')
		else:
			raise PSTokenError('huh?')

	def push(self, object):
		self.stack.append(object)

	def pop(self, *types):
		stack = self.stack
		if not stack:
			raise PSError('stack underflow')
		object = stack[-1]
		if types:
			if object.type not in types:
				raise PSError('typecheck, expected %s, found %s' % (repr(types), object.type))
		del stack[-1]
		return object

	def do_makearray(self):
		array = []
		while 1:
			topobject = self.pop()
			if topobject == self.mark:
				break
			array.append(topobject)
		array.reverse()
		self.push(ps_array(array))

	def close(self):
		"""Remove circular references."""
		del self.stack
		del self.dictstack


def unpack_item(item):
	tp = type(item.value)
	if tp == dict:
		newitem = {}
		for key, value in item.value.items():
			newitem[key] = unpack_item(value)
	elif tp == list:
		newitem = [None] * len(item.value)
		for i in range(len(item.value)):
			newitem[i] = unpack_item(item.value[i])
		if item.type == 'proceduretype':
			newitem = tuple(newitem)
	else:
		newitem = item.value
	return newitem

def suckfont(data):
	import re
	m = re.search(br"/FontName\s+/([^ \t\n\r]+)\s+def", data)
	if m:
		fontName = m.group(1)
	else:
		fontName = None
	interpreter = PSInterpreter()
	interpreter.interpret(b"/Helvetica 4 dict dup /Encoding StandardEncoding put definefont pop")
	interpreter.interpret(data)
	fontdir = interpreter.dictstack[0]['FontDirectory'].value
	if fontName in fontdir:
		rawfont = fontdir[fontName]
	else:
		# fall back, in case fontName wasn't found
		fontNames = list(fontdir.keys())
		if len(fontNames) > 1:
			fontNames.remove("Helvetica")
		fontNames.sort()
		rawfont = fontdir[fontNames[0]]
	interpreter.close()
	return unpack_item(rawfont)


if __name__ == "__main__":
	import EasyDialogs
	path = EasyDialogs.AskFileForOpen()
	if path:
		from fontTools import t1Lib
		data, kind = t1Lib.read(path)
		font = suckfont(data)