#!/usr/bin/env python3
"""
 Convert the X11 locale.alias file into a mapping dictionary suitable
 for locale.py.

 Written by Marc-Andre Lemburg <mal@genix.com>, 2004年12月10日.

"""
import locale
import sys
_locale = locale

# Location of the X11 alias file.
LOCALE_ALIAS = '/usr/share/X11/locale/locale.alias'
# Location of the glibc SUPPORTED locales file.
SUPPORTED = '/usr/share/i18n/SUPPORTED'

def parse(filename):

 with open(filename, encoding='latin1') as f:
 lines = list(f)
 # Remove mojibake in /usr/share/X11/locale/locale.alias.
 # b'\xef\xbf\xbd' == '\ufffd'.encode('utf-8')
 lines = [line for line in lines if '\xef\xbf\xbd' not in line]
 data = {}
 for line in lines:
 line = line.strip()
 if not line:
 continue
 if line[:1] == '#':
 continue
 locale, alias = line.split()
 # Fix non-standard locale names, e.g. ks_IN@devanagari.UTF-8
 if '@' in alias:
 alias_lang, _, alias_mod = alias.partition('@')
 if '.' in alias_mod:
 alias_mod, _, alias_enc = alias_mod.partition('.')
 alias = alias_lang + '.' + alias_enc + '@' + alias_mod
 # Strip ':'
 if locale[-1] == ':':
 locale = locale[:-1]
 # Lower-case locale
 locale = locale.lower()
 # Ignore one letter locale mappings (except for 'c')
 if len(locale) == 1 and locale != 'c':
 continue
 # Normalize encoding, if given
 if '.' in locale:
 lang, encoding = locale.split('.')[:2]
 encoding = encoding.replace('-', '')
 encoding = encoding.replace('_', '')
 locale = lang + '.' + encoding
 data[locale] = alias
 return data

def parse_glibc_supported(filename):

 with open(filename, encoding='latin1') as f:
 lines = list(f)
 data = {}
 for line in lines:
 line = line.strip()
 if not line:
 continue
 if line[:1] == '#':
 continue
 line = line.replace('/', ' ').strip()
 line = line.rstrip('\\').rstrip()
 words = line.split()
 if len(words) != 2:
 continue
 alias, alias_encoding = words
 # Lower-case locale
 locale = alias.lower()
 # Normalize encoding, if given
 if '.' in locale:
 lang, encoding = locale.split('.')[:2]
 encoding = encoding.replace('-', '')
 encoding = encoding.replace('_', '')
 locale = lang + '.' + encoding
 # Add an encoding to alias
 alias, _, modifier = alias.partition('@')
 alias = _locale._replace_encoding(alias, alias_encoding)
 if modifier and not (modifier == 'euro' and alias_encoding == 'ISO-8859-15'):
 alias += '@' + modifier
 data[locale] = alias
 return data

def pprint(data):
 items = sorted(data.items())
 for k, v in items:
 print(' %-40s%a,' % ('%a:' % k, v))

def print_differences(data, olddata):
 items = sorted(olddata.items())
 for k, v in items:
 if k not in data:
 print('# removed %a' % k)
 elif olddata[k] != data[k]:
 print('# updated %a -> %a to %a' % \
 (k, olddata[k], data[k]))
 # Additions are not mentioned

def optimize(data):
 locale_alias = locale.locale_alias
 locale.locale_alias = data.copy()
 for k, v in data.items():
 del locale.locale_alias[k]
 if locale.normalize(k) != v:
 locale.locale_alias[k] = v
 newdata = locale.locale_alias
 errors = check(data)
 locale.locale_alias = locale_alias
 if errors:
 sys.exit(1)
 return newdata

def check(data):
 # Check that all alias definitions from the X11 file
 # are actually mapped to the correct alias locales.
 errors = 0
 for k, v in data.items():
 if locale.normalize(k) != v:
 print('ERROR: %a -> %a != %a' % (k, locale.normalize(k), v),
 file=sys.stderr)
 errors += 1
 return errors

if __name__ == '__main__':
 import argparse
 parser = argparse.ArgumentParser()
 parser.add_argument('--locale-alias', default=LOCALE_ALIAS,
 help='location of the X11 alias file '
 '(default: %a)' % LOCALE_ALIAS)
 parser.add_argument('--glibc-supported', default=SUPPORTED,
 help='location of the glibc SUPPORTED locales file '
 '(default: %a)' % SUPPORTED)
 args = parser.parse_args()

 data = locale.locale_alias.copy()
 data.update(parse_glibc_supported(args.glibc_supported))
 data.update(parse(args.locale_alias))
 while True:
 # Repeat optimization while the size is decreased.
 n = len(data)
 data = optimize(data)
 if len(data) == n:
 break
 print_differences(data, locale.locale_alias)
 print()
 print('locale_alias = {')
 pprint(data)
 print('}')