"""
NL2BR Extension
===============

A Python-Markdown extension to treat newlines as hard breaks; like
GitHub-flavored Markdown does.

Usage:

    >>> import markdown
    >>> print markdown.markdown('line 1\\nline 2', extensions=['nl2br'])
    <p>line 1<br />
    line 2</p>

Copyright 2011 [Brian Neal](http://deathofagremmie.com/)

Dependencies:
* [Python 2.4+](http://python.org)
* [Markdown 2.1+](http://packages.python.org/Markdown/)

"""

from __future__ import absolute_import
from __future__ import unicode_literals
from . import Extension
from ..inlinepatterns import SubstituteTagPattern

BR_RE = r'\n'

class Nl2BrExtension(Extension):

    def extendMarkdown(self, md, md_globals):
        br_tag = SubstituteTagPattern(BR_RE, 'br')
        md.inlinePatterns.add('nl', br_tag, '_end')


def makeExtension(configs=None):
    return Nl2BrExtension(configs)