#!/usr/bin/env python3

import html
from os import path
from pathlib import Path
import re
from subprocess import run
from sys import argv


PROGRAM_RE = re.compile('\n'.join((
    r'NOM : (?P<name>[^\n]+)',
    r'COMPOSITEURS : (?P<composers>[^\n]+)',
    'DESCRIPTION :',
    '(?P<description>.+?)',
    'MORCEAUX :',
    r'(?P<pieces>(?:- [^\n]+\n)*- [^\n]+)'
)), flags=re.DOTALL)

def read_programs(programs):
    with open(programs) as f:
        return tuple(re.finditer(PROGRAM_RE, f.read()))


BLOCK_TEMPLATE = '''\
<details class="program">
  <summary>
    <div class="name">{name}</div>
    <div class="composers">{composers}</div>
    <img class="button open" src="{imgdir}/chevron-down.svg">
    <img class="button close" src="{imgdir}/chevron-up.svg">
  </summary>
{description}
<ol class="pieces">
{pieces}
</ol>
</details>
'''

def piece(p):
    if p in ('entracte', 'intermission'):
        return f'<li class="intermission">{p}</li>'
    return f'<li>{html.escape(p)}</li>'

def pandoc(md):
    return run(
        ('pandoc',),
        input=md, capture_output=True, text=True, check=True
    ).stdout

def print_program(info):
    info['name'] = re.sub(
        '<p>(.+)</p>', r'\1', pandoc(info['name'])
    )
    info['description'] = pandoc(info['description'])

    info['pieces'] = '\n'.join(
        piece(p[2:])            # Assume p.startswith('- ').
        for p in info['pieces'].splitlines()
    )

    print(BLOCK_TEMPLATE.format_map(info))


def main(programs_src):
    # pathlib.Path(x).relative_to(y) cannot handle y not being under x,
    # os.path.relpath('x') yields '' rather than '.'.
    # 😮‍💨
    imgdir = path.relpath('images', Path(programs_src).parent)

    for p in read_programs(programs_src):
        info = p.groupdict()
        info['imgdir'] = imgdir
        print_program(info)


if __name__ == '__main__':
    main(argv[1])