#!/usr/bin/env python3

import configparser
import sys
from pathlib import Path

REPO_ROOT = Path(__file__).resolve().parents[1]

def main():
    scriv_config = configparser.ConfigParser()
    scriv_config.read(REPO_ROOT / 'changelog.d/scriv.ini')

    scriv_section = scriv_config['scriv']
    assert scriv_section['format'] == 'md'

    md_header_level = int(scriv_section['md_header_level'])
    md_header_prefix = '#' * md_header_level + '# '

    categories = {s.strip() for s in scriv_section['categories'].split(',')}

    success = True

    def complain(message):
        nonlocal success
        success = False
        print(f"{fragment_path.relative_to(REPO_ROOT)}:{line_index+1}: {message}", file=sys.stderr)

    for fragment_path in REPO_ROOT.glob('changelog.d/*.md'):
        with open(fragment_path) as fragment_file:
            for line_index, line in enumerate(fragment_file):
                if not line.startswith(md_header_prefix):
                    # The first line should be a header, and all headers should be of appropriate level.
                    if line_index == 0 or line.startswith('#'):
                        complain(f"line should start with {md_header_prefix!r}")
                    continue

                category = line.removeprefix(md_header_prefix).strip()
                if category not in categories:
                    complain(f"unknown category: {category}")

    sys.exit(0 if success else 1)

main()