#!/usr/bin/env python

"""
Pandoc filter to convert divs with class="theorem" to LaTeX
theorem environments in LaTeX output, and to numbered theorems
in HTML output.
"""

from pandocfilters import toJSONFilter, RawBlock, Div

theoremcount = 0

def latex(x):
  return RawBlock('latex',x)

def html(x):
  return RawBlock('html', x)

def theorems(key, value, format, meta):
  if key == 'Div':
    [[ident,classes,kvs], contents] = value
    if "theorem" in classes:
      if format == "latex":
        if ident == "":
          label = ""
        else:
          label = '\\label{' + ident + '}'
        return([latex('\\begin{theorem}' + label)] + contents +
               [latex('\\end{theorem}')])
      elif format == "html" or format == "html5":
        global theoremcount
        theoremcount = theoremcount + 1
        newcontents = [html('<dt>Theorem ' + str(theoremcount) + '</dt>'),
                       html('<dd>')] + contents + [html('</dd>\n</dl>')]
        return Div([ident,classes,kvs], newcontents)

if __name__ == "__main__":
  toJSONFilter(theorems)