# (Be in -*- python -*- mode.)
#
# ====================================================================
# Copyright (c) 2006 CollabNet.  All rights reserved.
#
# This software is licensed as described in the file COPYING, which
# you should have received as part of this distribution.  The terms
# are also available at http://subversion.tigris.org/license-1.html.
# If newer versions of this license are posted there, you may use a
# newer version instead, at your option.
#
# This software consists of voluntary contributions made by many
# individuals.  For exact contribution history, see the revision
# history and logs, available at http://cvs2svn.tigris.org/.
# ====================================================================

"""This module contains classes to transform symbol names."""


from __future__ import generators

import re

from cvs2svn_lib.boolean import *


class SymbolTransform:
  """Transform symbol names arbitrarily."""

  def transform(self, cvs_file, symbol_name):
    """Possibly transform SYMBOL_NAME, which was found in CVS_FILE.

    Return the transformed symbol name.  If this SymbolTransform
    doesn't apply, return the original SYMBOL_NAME.

    This method is free to use the information inf CVS_FILE (including
    CVS_FILE.project) to decide whether and/or how to transform
    SYMBOL_NAME."""

    raise NotImplementedError()


class RegexpSymbolTransform(SymbolTransform):
  def __init__(self, pattern, replacement):
    self.pattern = re.compile(pattern)
    self.replacement = replacement

  def transform(self, cvs_file, symbol_name):
    return self.pattern.sub(self.replacement, symbol_name)