mdrenderer.py

# coding: utf-8

"""
Markdown renderer
=================

This class renders parsed markdown back to markdown.
It is useful for automatic modifications of the md contents.

## Authors and License

Copyright (C) 2015 Jaroslav Kysela

License: WTFPL 2
"""

from mistune import Renderer

class Object:

   pass

class MdRenderer(Renderer):

  def get_block(text):
    type = text[0]
    p = text.find(':')
    if p <= 0:
      return ('', '', '')
    l = int(text[1:p])
    t = text[p+1:p+1+l]
    return (text[p+1+l:], type, t)

  def newline(self):
    return '\n'

  def text(self, text):
    return text

  def linebreak(self):
    return '\n'

  def hrule(self):
    return '---\n'

  def header(self, text, level, raw=None):
    return '#'*(level+1) + text + '\n\n'

  def paragraph(self, text):
    return text + '\n\n'

  def list(self, text, ordered=True):
    r = ''
    while text:
      text, type, t = MdRenderer.get_block(text)
      if type == 'l':
        r += (ordered and ('# ' + t) or ('* ' + t)) + '\n'
    return r

  def list_item(self, text):
    return 'l' + str(len(text)) + ':' + text

  def block_code(self, code, lang=None):
    return '```no-highlight\n' + code + '\n```\n'

  def block_quote(self, text):
    r = ''
    for line in text.splitlines():
      r += (line and '> ' or '') + line + '\n'
    return r

  def _emphasis(self, text, pref):
    return pref + text + pref + ' '

  def emphasis(self, text):
    return self._emphasis(text, '_')

  def double_emphasis(self, text):
    return self._emphasis(text, '__')

  def strikethrough(self, text):
    return self._emphasis(text, '~~')

  def codespan(self, text):
    return '`' + text + '`'

  def autolink(self, link, is_email=False):
    return '<' + link + '>'

  def link(self, link, title, text, image=False):
    r = (image and '!' or '') + '[' + text + '](' + link + ')'
    if title:
      r += '"' + title + '"'
    return r

  def image(self, src, title, text):
    self.link(src, title, text, image=True)

  def table(self, header, body):
    hrows = []
    while header:
      header, type, t = MdRenderer.get_block(header)
      if type == 'r':
        flags = {}
        cols = []
        while t:
          t, type2, t2 = MdRenderer.get_block(t)
          if type2 == 'f':
            fl, v = t2.split('=')
            flags[fl] = v
          elif type2 == 'c':
            c = Object()
            c.flags = flags
            c.text = t2
            cols.append(c)
        hrows.append(cols)
    brows = []
    while body:
      body, type, t = MdRenderer.get_block(body)
      if type == 'r':
        flags = {}
        cols = []
        while t:
          t, type2, t2 = MdRenderer.get_block(t)
          if type2 == 'f':
            fl, v = t2.split('=')
            flags[fl] = v
          elif type2 == 'c':
            c = Object()
            c.flags = flags
            c.text = t2
            cols.append(c)
        brows.append(cols)
    colscount = 0
    colmax = [0] * 100
    align = [''] * 100
    for row in hrows + brows:
      colscount = max(len(row), colscount)
      i = 0
      for col in row:
        colmax[i] = max(len(col.text), colmax[i])
        if 'align' in col.flags:
          align[i] = col.flags['align'][0]
        i += 1
    r = ''
    for row in hrows:
      i = 0
      for col in row:
        if i > 0:
          r += ' | '
        r += col.text.ljust(colmax[i])
        i += 1
      r += '\n'
    for i in range(colscount):
      if i > 0:
        r += ' | '
      if align[i] == 'c':
        r += ':' + '-'.ljust(colmax[i]-2, '-') + ':'
      elif align[i] == 'l':
        r += ':' + '-'.ljust(colmax[i]-1, '-')
      elif align[i] == 'r':
        r +=  '-'.ljust(colmax[i]-1, '-') + ':'
      else:
        r += '-'.ljust(colmax[i], '-')
    r += '\n'
    for row in brows:
      i = 0
      for col in row:
        if i > 0:
          r += ' | '
        r += col.text.ljust(colmax[i])
        i += 1
      r += '\n'
    return r

  def table_row(self, content):
    return 'r' + str(len(content)) + ':' + content

  def table_cell(self, content, **flags):
    content = content.replace('\n', ' ')
    r = ''
    for fl in flags:
      v = flags[fl]
      if type(v) == type(True):
        v = v and 1 or 0
      v = str(v) and str(v) or ''
      r += 'f' + str(len(fl) + 1 + len(v)) + ':' + fl + '=' + v
    return r + 'c' + str(len(content)) + ':' + content

  def footnote_ref(self, key, index):
    return '[^' + str(index) + ']'

  def footnote_item(self, key, text):
    r = '[^' + str(index) + ']:\n'
    for l in text.split('\n'):
      r += '  ' + l.lstrip().rstrip() + '\n'
    return r

  def footnotes(self, text):
    return text