# -*- coding: utf-8 -*-
import os
import shutil
from subprocess import call, PIPE
from tempfile import mkdtemp
from librarian import get_resource
from . import DataEmbed, create_embed, downgrades_to


class LaTeX(DataEmbed):
    @downgrades_to('image/png')
    def to_png(self):
        tmpl = open(get_resource('res/embeds/latex/template.tex')).read().decode('utf-8')
        tempdir = mkdtemp('-librarian-embed-latex')
        fpath = os.path.join(tempdir, 'doc.tex')
        with open(fpath, 'w') as f:
            f.write((tmpl % {'code': self.data}).encode('utf-8'))
        call(['xelatex', '-interaction=batchmode', '-output-directory', tempdir, fpath], stdout=PIPE, stderr=PIPE)
        call(['convert', '-density', '150', os.path.join(tempdir, 'doc.pdf'), '-trim',
             os.path.join(tempdir, 'doc.png')])
        pngdata = open(os.path.join(tempdir, 'doc.png')).read()
        shutil.rmtree(tempdir)
        return create_embed('image/png', data=pngdata)