Create a copy of the build_font.py

#!/usr/bin/env python

# Copyright (C) 2014 The Android Open Source Project

#

# Licensed under the Apache License, Version 2.0 (the 'License');

# you may not use this file except in compliance with the License.

# You may obtain a copy of the License at

#

#      http://www.apache.org/licenses/LICENSE-2.0

#

# Unless required by applicable law or agreed to in writing, software

# distributed under the License is distributed on an 'AS IS' BASIS,

# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

# See the License for the specific language governing permissions and

# limitations under the License.

"""

Rename the PS name of all fonts in the input directories and copy them to the

output directory.

Usage: build_font.py /path/to/input_fonts1/ /path/to/input_fonts2/ /path/to/output_fonts/

"""

import glob

from multiprocessing import Pool

import os

import re

import shutil

import sys

import xml.etree.ElementTree as etree

# Prevent .pyc files from being created.

sys.dont_write_bytecode = True

# fontTools is available at platform/external/fonttools

from fontTools import ttx

# global variable

dest_dir = '/tmp'

class FontInfo(object):

  family = None

  style = None

  version = None

  ends_in_regular = False

  fullname = None

class InvalidFontException(Exception):

  pass

# These constants represent the value of nameID parameter in the namerecord for

# different information.

# see http://scripts.sil.org/cms/scripts/page.php?item_id=IWS-Chapter08#3054f18b

NAMEID_FAMILY = 1

NAMEID_STYLE = 2

NAMEID_FULLNAME = 4

NAMEID_VERSION = 5

def main(argv):

  if len(argv) < 2:

    sys.exit('Usage: build_font.py /path/to/input_fonts/ /path/to/out/dir/')

  for directory in argv:

    if not os.path.isdir(directory):

      sys.exit(directory + ' is not a valid directory')

  global dest_dir

  dest_dir = argv[-1]

  src_dirs = argv[:-1]

  cwd = os.getcwd()

  os.chdir(dest_dir)

  files = glob.glob('*')

  for filename in files:

    os.remove(filename)

  os.chdir(cwd)

  input_fonts = list()

  for src_dir in src_dirs:

    for dirname, dirnames, filenames in os.walk(src_dir):

      for filename in filenames:

        input_path = os.path.join(dirname, filename)

        extension = os.path.splitext(filename)[1].lower()

        if extension == '.ttf':

          input_fonts.append(input_path)

        elif extension == '.xml':

          shutil.copy(input_path, dest_dir)

      if '.git' in dirnames:

        # don't go into any .git directories.

        dirnames.remove('.git')

  # Create as many threads as the number of CPUs

  pool = Pool(processes=None)

  pool.map(convert_font, input_fonts)

def convert_font(input_path):

  filename = os.path.basename(input_path)

  print 'Converting font: ' + filename

  # the path to the output file. The file name is the fontfilename.ttx

  ttx_path = os.path.join(dest_dir, filename)

  ttx_path = ttx_path[:-1] + 'x'

  try:

    # run ttx to generate an xml file in the output folder which represents all

    # its info

    ttx_args = ['-q', '-d', dest_dir, input_path]

    ttx.main(ttx_args)

    # now parse the xml file to change its PS name.

    tree = etree.parse(ttx_path)

    root = tree.getroot()

    for name in root.iter('name'):

      update_tag(name, get_font_info(name))

    tree.write(ttx_path, xml_declaration=True, encoding='utf-8')

    # generate the udpated font now.

    ttx_args = ['-q', '-d', dest_dir, ttx_path]

    ttx.main(ttx_args)

  except InvalidFontException:

    # In case of invalid fonts, we exit.

    print filename + ' is not a valid font'

    raise

  except Exception as e:

    print 'Error converting font: ' + filename

    print e

    # Some fonts are too big to be handled by the ttx library.

    # Just copy paste them.

    shutil.copy(input_path, dest_dir)

  try:

    # delete the temp ttx file is it exists.

    os.remove(ttx_path)

  except OSError:

    pass

def get_font_info(tag):

  """ Returns a list of FontInfo representing the various sets of namerecords

      found in the name table of the font. """

  fonts = []

  font = None

  last_name_id = sys.maxint

  for namerecord in tag.iter('namerecord'):

    if 'nameID' in namerecord.attrib:

      name_id = int(namerecord.attrib['nameID'])

      # A new font should be created for each platform, encoding and language

      # id. But, since the nameIDs are sorted, we use the easy approach of

      # creating a new one when the nameIDs reset.

      if name_id <= last_name_id and font is not None:

        fonts.append(font)

        font = None

      last_name_id = name_id

      if font is None:

        font = FontInfo()

      if name_id == NAMEID_FAMILY:

        font.family = namerecord.text.strip()

      if name_id == NAMEID_STYLE:

        font.style = namerecord.text.strip()

      if name_id == NAMEID_FULLNAME:

        font.ends_in_regular = ends_in_regular(namerecord.text)

        font.fullname = namerecord.text.strip()

      if name_id == NAMEID_VERSION:

        font.version = get_version(namerecord.text)

  if font is not None:

    fonts.append(font)

  return fonts

def update_tag(tag, fonts):

  last_name_id = sys.maxint

  fonts_iterator = fonts.__iter__()

  font = None

  for namerecord in tag.iter('namerecord'):

    if 'nameID' in namerecord.attrib:

      name_id = int(namerecord.attrib['nameID'])

      if name_id <= last_name_id:

        font = fonts_iterator.next()

        font = update_font_name(font)

      last_name_id = name_id

      if name_id == NAMEID_FAMILY:

        namerecord.text = font.family

      if name_id == NAMEID_FULLNAME:

        namerecord.text = font.fullname

def update_font_name(font):

  """ Compute the new font family name and font fullname. If the font has a

      valid version, it's sanitized and appended to the font family name. The

      font fullname is then created by joining the new family name and the

      style. If the style is 'Regular', it is appended only if the original font

      had it. """

  if font.family is None or font.style is None:

    raise InvalidFontException('Font doesn\'t have proper family name or style')

  if font.version is not None:

    new_family = font.family + font.version

  else:

    new_family = font.family

  if font.style is 'Regular' and not font.ends_in_regular:

    font.fullname = new_family

  else:

    font.fullname = new_family + ' ' + font.style

  font.family = new_family

  return font

def ends_in_regular(string):

  """ According to the specification, the font fullname should not end in

      'Regular' for plain fonts. However, some fonts don't obey this rule. We

      keep the style info, to minimize the diff. """

  string = string.strip().split()[-1]

  return string is 'Regular'

def get_version(string):

  # The string must begin with 'Version n.nn '

  # to extract n.nn, we return the second entry in the split strings.

  string = string.strip()

  if not string.startswith('Version '):

    raise InvalidFontException('mal-formed font version')

  return sanitize(string.split()[1])

def sanitize(string):

  return re.sub(r'[^\w-]+', '', string)

if __name__ == '__main__':

  main(sys.argv[1:])