#!/usr/bin/env python3
"""Compile the main article in a temporary directory and copy the PDF out."""
from pathlib import Path
import argparse
import shutil
import subprocess
import sys
import tempfile

ROOT = Path(__file__).resolve().parent
PACKAGE = ROOT.parent


def main() -> None:
    parser = argparse.ArgumentParser(description=__doc__)
    parser.add_argument('--output-dir', type=Path, default=PACKAGE,
                        help='Directory for main.pdf; defaults to the package root.')
    args = parser.parse_args()
    tex = shutil.which('pdflatex')
    bib = next((shutil.which(name) for name in ('bibtex', 'bibtex.original', 'bibtex8')
                if shutil.which(name)), None)
    if tex is None or bib is None:
        raise RuntimeError('pdfLaTeX and BibTeX are required.')
    with tempfile.TemporaryDirectory(prefix='dis-dae-build-') as directory:
        work = Path(directory)
        for name in ('main.tex', 'references.bib'):
            shutil.copyfile(PACKAGE / name, work / name)
        for name in ('figures', 'tables'):
            shutil.copytree(PACKAGE / name, work / name)
        latex = [tex, '-interaction=nonstopmode', '-halt-on-error', 'main.tex']
        for command in (latex, [bib, 'main'], latex, latex):
            result = subprocess.run(command, cwd=work, text=True,
                                    stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
            print(result.stdout, end='', flush=True)
            if result.returncode:
                raise RuntimeError('Compilation failed: ' + ' '.join(command))
        log = (work / 'main.log').read_text(errors='replace')
        problems = [message for message in (
            'There were undefined references', 'undefined on input line',
            'Missing character:', 'Overfull \\hbox', 'Overfull \\vbox'
        ) if message in log]
        if problems:
            raise RuntimeError('Typesetting warnings: ' + ', '.join(problems))
        args.output_dir.mkdir(parents=True, exist_ok=True)
        target = args.output_dir / 'main.pdf'
        shutil.copyfile(work / 'main.pdf', target)
    print('Built', target.resolve())


if __name__ == '__main__':
    try:
        main()
    except (OSError, RuntimeError) as exc:
        print(exc, file=sys.stderr)
        sys.exit(1)