# -*- coding: utf-8 -*-

"""
Primary version number source.

Forth element can be 'dev' < 'a' < 'b' < 'rc' < 'final'. An empty 4th
element is equivalent to 'final'.
"""
VERSION = (0, 3, 4, 'final')


def get_version():
    """Provide version number

    Use verlib format [1]_:
      N.N[.N]+[{a|b|c|rc}N[.N]+][.postN][.devN]

    .. [1] http://www.python.org/dev/peps/pep-0386/
    """
    main_version = '%s.%s.%s' % VERSION[0:3]

    if len(VERSION) < 4:
        return main_version

    version_type = VERSION[3]
    if not version_type or version_type == 'final':
        return main_version
    elif version_type == 'dev':
        return '%s.dev' % main_version
    else:
        return '%s%s' % (main_version, version_type)