#!/usr/bin/env python3
"""This demo script converts from markdown to Epub using GladTeX. It requires
Pandoc for the conversion.
Throughout this script, the abbreviation AST for Abstract Syntax Tree is used."""
import json
import os
import shutil
import subprocess
import sys
import gleetex
def transform_ast(ast):
# extract formulas from Pandoc document AST
formulas = gleetex.pandoc.extract_formulas(ast)
# converter using cache, helps avoiding the same formula twice
conv = gleetex.cachedconverter.CachedConverter('.', True,
encoding="UTF-8")
# automatically handle unicode
conv.set_replace_nonascii(True)
# go parallel
conv.convert_all('.', formulas)
# an converted image has information like image depth and height, adjust
# data structure for write-back
formulas = [conv.get_data_for(eqn, style) for _p, style, eqn in formulas]
# get a formatter instance
with gleetex.htmlhandling.HtmlImageFormatter(".") as img_fmt:
# non-ascii sequences will be replaced in the laternative text
img_fmt.set_replace_nonascii(True)
# this alters the AST reference, so no return value required
gleetex.pandoc.replace_formulas_in_ast(img_fmt, ast['blocks'],
formulas)
def cleanup(path):
# remove images and ache, relevant data is included within the EPUB
for file in os.listdir(path):
if file.endswith('.png') or file.endswith('.cache'):
os.remove(os.path.join(path, file))
def main():
for prog in ('pandoc', 'gladtex'):
if not shutil.which(prog):
sys.stderr.write(('This script requires %s, please install and rerun '
'this script.') % prog)
sys.exit(1)
usage = False
if len(sys.argv) < 2:
print("Missing command arguments.")
usage = True
elif len(sys.argv) > 2 or (len(sys.argv) == 2 and not
os.path.exists(sys.argv[1])):
print("Exactly one input path required")
usage = True
if usage:
print("%s <INPUTFILE>\n\nConvert given file to epub using GladTeX." % \
sys.argv[0])
sys.exit(0)
inputfile = sys.argv[1]
outputfile = '%s.epub' % os.path.splitext(inputfile)[0]
# get the document AST
proc = subprocess.Popen(['pandoc', '-t', 'json', inputfile],
stdout=subprocess.PIPE)
ast = json.loads(proc.communicate()[0].decode(sys.getdefaultencoding()))
if proc.wait() != 0:
sys.exit(2)
# the actual GleeTeX calls are here
transform_ast(ast)
# write back to stdin of pandoc
proc = subprocess.Popen(['pandoc', '-o', outputfile, '-f', 'json', '-t',
'epub'], stdin=subprocess.PIPE)
proc.communicate(json.dumps(ast).encode(sys.getdefaultencoding()))
if proc.wait():
sys.exit(2)
cleanup('.')
