#!/usr/bin/python2.5

#

# Copyright 2008 the Melange authors.

#

# Licensed under the Apache License, Version 2.0 (the "License");

# you may not use this file except in compliance with the License.

# You may obtain a copy of the License at

#

#   http://www.apache.org/licenses/LICENSE-2.0

#

# Unless required by applicable law or agreed to in writing, software

# distributed under the License is distributed on an "AS IS" BASIS,

# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

# See the License for the specific language governing permissions and

# limitations under the License.

"""Helpers for manipulating templates.

"""

__authors__ = [

  '"Todd Larsen" <tlarsen@google.com>',

  ]

def makeSiblingTemplatesList(templates, new_template_file,

                             default_template=None):

  """Converts template paths into a list of "sibling" templates.

  Args:

    templates: search list of templates (or just a single template not in a

      list) from which template paths will be extracted (discarding the final

      template file name of each template)

    new_template_file: new "sibling" template file to append to each extracted

      template path

    default_template: a default template (or a list of them) to append to the

      end of the generated "sibling" template paths; default is None

  Returns:

    A list of potential "sibling" templates named by new_template_file located

    in the paths of the templates in the supplied list.  For example, from:

      ['foo/bar/the_old_template.html', 'foo/the_old_template.html']

    to:

      ['foo/bar/some_new_template.html', 'foo/some_new_template.html']

  """

  if not isinstance(templates, (list, tuple)):

    templates = [templates]

  if default_template is None:

    default_template = []

  if not isinstance(default_template, (list, tuple)):

    default_template = [default_template]

  sibling_templates = [

    '%s/%s' % (t.rsplit('/', 1)[0], new_template_file) for t in templates]

  return sibling_templates + default_template