from django.core.urlresolvers import reverse
import markdown
from markdown.inlinepatterns import Pattern
from markdown.util import etree
import boards

__author__ = 'neko259'


class AutolinkPattern(Pattern):
    def handleMatch(self, m):
        link_element = etree.Element('a')
        href = m.group(2)
        link_element.set('href', href)
        link_element.text = href

        return link_element


class QuotePattern(Pattern):
    def handleMatch(self, m):
        quote_element = etree.Element('span')
        quote_element.set('class', 'quote')
        quote_element.text = m.group(2)

        return quote_element


class ReflinkPattern(Pattern):
    def handleMatch(self, m):
        ref_element = etree.Element('a')
        post_id = m.group(4)
        ref_element.set('href', reverse(boards.views.jump_to_post,
                                        kwargs={'post_id': post_id}))
        ref_element.text = m.group(2)

        return ref_element


class SpoilerPattern(Pattern):
    def handleMatch(self, m):
        quote_element = etree.Element('span')
        quote_element.set('class', 'spoiler')
        quote_element.text = m.group(2)

        return quote_element


class CommentPattern(Pattern):
    def handleMatch(self, m):
        quote_element = etree.Element('span')
        quote_element.set('class', 'comment')
        quote_element.text = '//' + m.group(3)

        return quote_element


class NeboardMarkdown(markdown.Extension):
    AUTOLINK_PATTERN = r'(https?://\S+)'
    QUOTE_PATTERN = r'^(?<!>)(>[^>]+)$'
    REFLINK_PATTERN = r'((>>)(\d+))'
    SPOILER_PATTERN = r'%%(.+)%%'
    COMMENT_PATTERN = r'^(//(.+))'

    def extendMarkdown(self, md, md_globals):
        self._add_neboard_patterns(md)
        self._delete_patterns(md)

    def _delete_patterns(self, md):
        del md.parser.blockprocessors['quote']

        del md.inlinePatterns['image_link']
        del md.inlinePatterns['image_reference']

    def _add_neboard_patterns(self, md):
        autolink = AutolinkPattern(self.AUTOLINK_PATTERN, md)
        quote = QuotePattern(self.QUOTE_PATTERN, md)
        reflink = ReflinkPattern(self.REFLINK_PATTERN, md)
        spoiler = SpoilerPattern(self.SPOILER_PATTERN, md)
        comment = CommentPattern(self.COMMENT_PATTERN, md)

        md.inlinePatterns[u'autolink_ext'] = autolink
        md.inlinePatterns[u'spoiler'] = spoiler
        md.inlinePatterns[u'comment'] = comment
        md.inlinePatterns[u'reflink'] = reflink
        md.inlinePatterns[u'quote'] = quote


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

neboard_extension = makeExtension()


def markdown_extended(markup):
    return markdown.markdown(markup, [neboard_extension], safe_mode=True)