#!/usr/bin/python3

from io import BytesIO
import os
import subprocess
import random
from string import ascii_letters
from subprocess import PIPE
import sys

from PIL import Image

LATEX_TEMPLATE = r'''
\documentclass{{minimal}}
\begin{{document}}
$$
{}
$$
\end{{document}}
'''

dpi = 1024
padding = 72

run = lambda args: subprocess.run(args, stdout=PIPE, stderr=PIPE)
filename = "".join(random.choices(ascii_letters, k=8))
tex_fn = filename + '.tex'
try:
    with open(tex_fn, 'w') as f:
        f.write(LATEX_TEMPLATE.format(' '.join(sys.argv[2:])))

    ps = run(['latex', '-interaction=nonstopmode', tex_fn])
    print(ps.stdout.decode(), ps.stderr.decode())
    ps.check_returncode()

    ps = run(['dvipng', '-q', '-T', 'tight', '-D', str(dpi), filename + '.dvi', '-o', filename + '.png'])
    print(ps.stdout.decode(), ps.stderr.decode())
    ps.check_returncode()

    img = Image.open(filename + '.png')
    new_img = Image.new('RGB', (img.width + padding * 2, img.height + padding * 2), (255, 255, 255))
    new_img.paste(img, (padding, padding))
    new_img.save(sys.argv[1] + ".png", 'png')

finally:
    for fn in [f'{filename}.{ext}' for ext in ('aux', 'dvi', 'log', 'tex', 'png')] + ['texput.log']:
        if os.path.isfile(fn):
            os.remove(fn)