#!/usr/bin/env python3
#  -*- encoding: utf-8 -*-

""" Minimalist Python ctypes wrapper for Unitex

author: Miguel Olivares <miguel@moliware.com>

On Aug 9th, 2017:
edited by: Adler Neves <adlerosn@gmail.com>
Changed:
 - Added multitons project pattern
 - Added string-to-byte conversion on argv
 - Added debug boolean, which activates a print
 - Added commandline option instead of loading SharedObject (good part: if external code crash, your code won't crash together)

"""
__author__ = "Miguel Olivares"
__email__ = "miguel@moliware.com"
__title__ = 'pyunitex'
__description__ = 'Minimalist Python ctypes wrapper for Unitex'
__license__ = 'LGPL-3.0'
__copyright__ = 'Copyright 2011 Miguel Olivares'
__version__ = '0.2'

import ctypes
import os
import subprocess

# Load library
unitex_lib_default = 'libunitex.so' if os.name == 'posix' else 'unitex.dll'
unitex_multitons = dict()

debugPrint = False

class Unitex(object):
    def __init__(self, unitex_lib = unitex_lib_default, useCommandline = False):
        self.useCommandline = useCommandline
        self.unitex = None
        if not useCommandline:
            if unitex_lib not in unitex_multitons:
                unitex_multitons[unitex_lib] = ctypes.cdll.LoadLibrary(unitex_lib)
            self.unitex = unitex_multitons[unitex_lib]
    
    """ Create a callable class for an operation"""
    def __getattr__(self, operation):
        """ Return an operation class """
        return UnitexOperation(self.useCommandline, self.unitex, operation)

class UnitexOperation(object):
    """ Execute any operation of UnitexTool"""
    def __init__(self, useCommandline, unitex, operation):
        self.useCommandline = useCommandline
        self.unitex = unitex
        """ It's allowed every operation of UnitexTool """
        self.operation = operation

    def __call__(self, *params):
        params_list = ["UnitexTool", self.operation] + list(params)
        if not self.useCommandline:
            """ Execute operation """
            # Build argv
            argv_type = ctypes.c_char_p * len(params_list)
            argv = argv_type(*[bytes(param, 'utf-8') for param in params_list])
            # Build argc
            argc = ctypes.c_int(len(argv))
            
            if debugPrint:
                print(params_list, flush=True)
    
            return self.unitex.main_UnitexTool(argc, argv)
        else:
            params_list[0] = self.useCommandline
            
            if debugPrint:
                print(params_list, flush=True)
            
            return subprocess.run(params_list, stdout=subprocess.PIPE)