rst2beamer.py

#!/usr/bin/env python
# encoding: utf-8
"""
A docutils script converting restructured text into Beamer-flavoured LaTeX.

Beamer is a LaTeX document class for presentations. Via this script, ReST can
be used to prepare slides. It can be called::

        rst2beamer.py infile.txt > outfile.tex
        
where ``infile.tex`` contains the produced Beamer LaTeX.

See <http:www.agapow.net/programming/python/rst2beamer> for more details.

"""
# TODO: modifications for handout sections?
# TOOD: sections and subsections?
# TODO: enable beamer themes?
# TODO: convert document metadata to front page fields?
# TODO: toc-conversion?
# TODO: fix descriptions

# Unless otherwise stated, created by P-M Agapow on 2007-08-21
# and open for academic & non-commercial use and modification .

__docformat__ = 'restructuredtext en'
__author__ = "Paul-Michael Agapow <agapow@bbsrc.ac.uk>"
__version__ = "0.2"


### IMPORTS ###

import locale
from docutils.core import publish_cmdline, default_description
from docutils.writers.latex2e import Writer as Latex2eWriter
from docutils.writers.latex2e import LaTeXTranslator, DocumentClass
from docutils import nodes

## CONSTANTS & DEFINES: ###

BEAMER_SPEC =   (
        'Beamer options',
        'These are derived almost entirely from the LaTeX2e options',
        tuple (
                [
                        (
                                'Specify theme.',
                                ['--theme'],
                                {'default': '', }
                        ),
                        (
                                'Specify document options.       Multiple options can be given, '
                                'separated by commas.  Default is "10pt,a4paper".',
                                ['--documentoptions'],
                                {'default': '', }
                        ),
                ] + list (Latex2eWriter.settings_spec[2][2:])
        ),
)

BEAMER_DEFAULTS = {
        'output_encoding': 'latin-1',
        'documentclass': 'beamer',
}


### IMPLEMENTATION ###

try:
         locale.setlocale (locale.LC_ALL, '')
except:
         pass

class BeamerTranslator (LaTeXTranslator):
        """
        A converter for docutils elements to beamer-flavoured latex.
        """

        def __init__ (self, document):
                LaTeXTranslator.__init__ (self, document)
                self.head_prefix = [x for x in self.head_prefix if ('{typearea}' not in x)]
                hyperref_posn = [i for i in range (len (self.head_prefix)) if ('{hyperref}' in self.head_prefix[i])]
                self.head_prefix[hyperref_posn[0]] = '\\usepackage{hyperref}\n'
                self.head_prefix.extend ([
                        '\\definecolor{rrblitbackground}{rgb}{0.55, 0.3, 0.1}\n',
                        '\\newenvironment{rtbliteral}{\n',
                        '\\begin{ttfamily}\n',
                        '\\color{rrblitbackground}\n',
                        '}{\n',
                        '\\end{ttfamily}\n',
                        '}\n',
                ])
                # this fixes the hardcoded section titles in docutils 0.4
                self.d_class = DocumentClass ('article')

        def begin_frametag (self):
                return '\\begin{frame}\n'

        def end_frametag (self):
                return '\\end{frame}\n'

        def visit_section (self, node):
                if (self.section_level == 0):
                        self.body.append (self.begin_frametag())
                LaTeXTranslator.visit_section (self, node)

        def depart_section (self, node):
                # Remove counter for potential subsections:
                LaTeXTranslator.depart_section (self, node)
                if (self.section_level == 0):
                        self.body.append (self.end_frametag())

        def visit_title (self, node):
                if (self.section_level == 1):
                        self.body.append ('\\frametitle{%s}\n\n' % self.encode(node.astext()))
                        raise nodes.SkipNode
                else:
                        LaTeXTranslator.visit_title (self, node)

        def depart_title (self, node):
                if (self.section_level != 1):
                        LaTeXTranslator.depart_title (self, node)

        def visit_literal_block(self, node):
                 if not self.active_table.is_open():
                          self.body.append('\n\n\\smallskip\n\\begin{rtbliteral}\n')
                          self.context.append('\\end{rtbliteral}\n\\smallskip\n\n')
                 else:
                          self.body.append('\n')
                          self.context.append('\n')
                 if (self.settings.use_verbatim_when_possible and (len(node) == 1)
                                 # in case of a parsed-literal containing just a "**bold**" word:
                                 and isinstance(node[0], nodes.Text)):
                          self.verbatim = 1
                          self.body.append('\\begin{verbatim}\n')
                 else:
                          self.literal_block = 1
                          self.insert_none_breaking_blanks = 1

        def depart_literal_block(self, node):
                if self.verbatim:
                        self.body.append('\n\\end{verbatim}\n')
                        self.verbatim = 0
                else:
                        self.body.append('\n')
                        self.insert_none_breaking_blanks = 0
                        self.literal_block = 0
                self.body.append(self.context.pop())


class BeamerWriter (Latex2eWriter):
        """
        A docutils writer that modifies the translator and settings for beamer.
        """
        settings_spec = BEAMER_SPEC
        settings_defaults = BEAMER_DEFAULTS

        def __init__(self):
                Latex2eWriter.__init__(self)
                self.translator_class = BeamerTranslator


if __name__ == '__main__':
        description = (
                "Generates Beamer-flavoured LaTeX for PDF-based presentations." + default_description)
        publish_cmdline (writer=BeamerWriter(), description=description)


### END ######################################################################