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

# This program is free software: you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation, either version 3 of the License, or

# (at your option) any later version.

#

# This program is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

# GNU General Public License for more details.

#

# You should have received a copy of the GNU General Public License

# along with this program.  If not, see <http://www.gnu.org/licenses/>.

"""

kallithea.lib.markup_renderer

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Renderer for markup languages with ability to parse using rst or markdown

This file was forked by the Kallithea project in July 2014.

Original author and date, and relevant copyright and licensing information is below:

:created_on: Oct 27, 2011

:author: marcink

:copyright: (c) 2013 RhodeCode GmbH, and others.

:license: GPLv3, see LICENSE.md for more details.

"""

import re

import logging

import traceback

from kallithea.lib.utils2 import safe_unicode, MENTIONS_REGEX

log = logging.getLogger(__name__)

url_re = re.compile(r'''(\bhttps?://(?:[\da-zA-Z0-9@:.-]+)'''

class MarkupRenderer(object):

    RESTRUCTUREDTEXT_DISALLOWED_DIRECTIVES = ['include', 'meta', 'raw']

    MARKDOWN_PAT = re.compile(r'md|mkdn?|mdown|markdown', re.IGNORECASE)

    RST_PAT = re.compile(r're?st', re.IGNORECASE)

    PLAIN_PAT = re.compile(r'readme', re.IGNORECASE)

    def _detect_renderer(self, source, filename=None):

        """

        runs detection of what renderer should be used for generating html

        from a markup language

        filename can be also explicitly a renderer name

        :param source:

        :param filename:

        """

        if MarkupRenderer.MARKDOWN_PAT.findall(filename):

            detected_renderer = 'markdown'

        elif MarkupRenderer.RST_PAT.findall(filename):

            detected_renderer = 'rst'

        elif MarkupRenderer.PLAIN_PAT.findall(filename):

            detected_renderer = 'rst'

        else:

            detected_renderer = 'plain'

        return getattr(MarkupRenderer, detected_renderer)

    @classmethod

    def _flavored_markdown(cls, text):

        """

        Github style flavored markdown

        :param text:

        """

        from hashlib import md5

        # Extract pre blocks.

        extractions = {}

        def pre_extraction_callback(matchobj):

            digest = md5(matchobj.group(0)).hexdigest()

            extractions[digest] = matchobj.group(0)

            return "{gfm-extraction-%s}" % digest

        pattern = re.compile(r'<pre>.*?</pre>', re.MULTILINE | re.DOTALL)

        text = re.sub(pattern, pre_extraction_callback, text)