opencc.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-

from ctypes import cast, cdll, c_char_p, c_int, c_size_t, c_void_p
from ctypes.util import find_library
import sys

class ConvertError(Exception):
  pass

class DictType:
  TEXT,DATRIE = 0,1

## @defgroup python_api Python API
#  API in python language

## OpenCC Python language binding
#  @ingroup python_api
class OpenCC:

  ## Constructor
  #  @param self The object pointer.
  #  @param config Filename of config.
  #  @param verbose Specifies whether error information is printed.
  #  @ingroup python_api
  def __init__(self, config=None, verbose=True):
    self.libopencc = cdll.LoadLibrary(find_library('opencc'))
    self.libopencc.opencc_open.restype = c_void_p
    self.libopencc.opencc_convert_utf8.argtypes = [c_void_p, c_char_p, c_size_t]
    # for checking for the returned '-1' pointer in case opencc_convert() fails.
    # c_char_p always tries to convert the returned (char *) to a Python string,
    self.libopencc.opencc_convert_utf8.restype = c_void_p
    self.libopencc.opencc_close.argtypes = [c_void_p]
    self.libopencc.opencc_perror.argtypes = [c_char_p]
    self.libopencc.opencc_dict_load.argtypes = [c_void_p, c_char_p, c_int]

    self.libc = cdll.LoadLibrary(find_library('c'))
    self.libc.free.argtypes = [c_void_p]

    self.config = config
    self.verbose = verbose
    self.od = None
  
  ## @deprecated
  def __enter__(self):
    if self.config is None:
      self.od = self.libopencc.opencc_open(0)
    else:
      self.od = self.libopencc.opencc_open(c_char_p(self.config))
    return self

  ## @deprecated
  def __exit__(self, type, value, traceback):
    self.libopencc.opencc_close(self.od)
    self.od = None

  def __perror(self, message):
    if self.verbose:
      self.libopencc.opencc_perror(message)

  ## Converts text.
  #  @param self The object pointer.
  #  @param text Input text.
  #  @return Converted text.
  #  @ingroup python_api
  def convert(self, text):
    retv_c = self.libopencc.opencc_convert_utf8(self.od, text, len(text))
    if retv_c == -1:
      self.__perror('OpenCC error:')
      raise ConvertError()
    retv_c = cast(retv_c, c_char_p)
    str_buffer = retv_c.value
    self.libc.free(retv_c);
    return str_buffer
  
  ## @deprecated
  def dict_load(self, filename, dicttype):
    retv = self.libopencc.opencc_dict_load(self.od, filename, dicttype)
    if retv == -1:
      self.__perror('OpenCC error:')
    return retv

if __name__ == "__main__":
  with sys.stdin as fp:
    text = fp.read()
  with OpenCC() as converter:
    for path in ['simp_to_trad_characters.ocd',
           'simp_to_trad_phrases.ocd']:
      converter.dict_load(path, DictType.DATRIE)
    print converter.convert(text)