# -*- coding: iso-8859-1 -*-

#  This software and supporting documentation are distributed by
#      Institut Federatif de Recherche 49
#      CEA/NeuroSpin, Batiment 145,
#      91191 Gif-sur-Yvette cedex
#      France
#
# This software is governed by the CeCILL-B license under
# French law and abiding by the rules of distribution of free software.
# You can  use, modify and/or redistribute the software under the 
# terms of the CeCILL-B license as circulated by CEA, CNRS
# and INRIA at the following URL "http://www.cecill.info". 
# 
# As a counterpart to the access to the source code and  rights to copy,
# modify and redistribute granted by the license, users are provided only
# with a limited warranty  and the software's author,  the holder of the
# economic rights,  and the successive licensors  have only  limited
# liability.
#
# In this respect, the user's attention is drawn to the risks associated
# with loading,  using,  modifying and/or developing or reproducing the
# software by the user in light of its specific status of free software,
# that may mean  that it is complicated to manipulate,  and  that  also
# therefore means  that it is reserved for developers  and  experienced
# professionals having in-depth computer knowledge. Users are therefore
# encouraged to load and test the software's suitability as regards their
# requirements in conditions enabling the security of their systems and/or 
# data to be ensured and,  more generally, to use and operate it in the 
# same conditions as regards security.
#
# The fact that you are presently reading this means that you have had
# knowledge of the CeCILL-B license and that you accept its terms.

'''
This module contains text related functions.

@author: Yann Cointepas
@organization: U{NeuroSpin<http://www.neurospin.org>} and U{IFR 49<http://www.ifr49.org>}
@license: U{CeCILL version 2<http://www.cecill.info/licences/Licence_CeCILL_V2-en.html>}
'''
__docformat__ = "epytext en"


def string_to_list( s ):
  s = s.strip( ' ' )
  while s:
    if s[0] == '"':
      i = 1
      while True:
        j = s[ i: ].find( '"' )
        if j == -1:
          # Syntax error, missing closing quote.
          # return the rest of the string and exit
          yield s[1:]
          return
        if s[ i + j - 1 ] == '\\':
          i = i + j + 1
        else:
          break
      yield s[ 1 : i+j ]
      s = s[ i+j+2: ].strip( ' ' )
    else:
      l = s.split( ' ', 1 )
      yield l[ 0 ]
      if len( l ) > 1:
        s = l[ 1 ].strip( ' ' )
      else:
        s = ''

def list_to_string( l ):
  return ' '.join( (quote_string( i ) for i in l ) )


def quote_string( unquoted ):
  if unquoted:
    if unquoted.find( ' ' ) > -1:
      return '"' + unquoted.replace( '"', '\\"' ) + '"'
    else:
      return unquoted
  return ''


def unquote_string( quoted ):
  if quoted and quoted[ 0 ] == '"':
    if quoted[ -1 ] == '"':
      quoted = quoted[ 1 : -1 ]
    else:
      # There is a syntax error here, quoted should
      # be terminated by a double quote
      quoted = quoted[ 1: ]
    return eval( 'r"' + quoted + '"' ).replace( '\\"', '"' )
  else:
    return quoted