#!/usr/bin/env python3
"""Insert {% include "_cascade/bar.html" . %} after <body> in freeze HTML.

Idempotent. Skips files that already contain the include or live under
_cascade/. Usage:

  python3 inject-cascade-bar.py /path/to/edition/root
"""
from __future__ import annotations

import re
import sys
from pathlib import Path

INCLUDE = '{% include "_cascade/bar.html" . %}'
BODY_RE = re.compile(r"(<body[^>]*>)", re.IGNORECASE)


def inject(text: str) -> str | None:
    if INCLUDE in text:
        return None
    if "_cascade/bar" in text:
        return None
    m = BODY_RE.search(text)
    if not m:
        return None
    i = m.end()
    return text[:i] + "\n" + INCLUDE + "\n" + text[i:]


def main() -> int:
    if len(sys.argv) != 2:
        print(f"usage: {sys.argv[0]} EDITION_ROOT", file=sys.stderr)
        return 2
    root = Path(sys.argv[1]).resolve()
    if not root.is_dir():
        print(f"not a dir: {root}", file=sys.stderr)
        return 2
    changed = 0
    scanned = 0
    for path in root.rglob("*.html"):
        if "/_cascade/" in path.as_posix() + "/":
            continue
        scanned += 1
        raw = path.read_text(encoding="utf-8", errors="ignore")
        out = inject(raw)
        if out is None:
            continue
        path.write_text(out, encoding="utf-8")
        changed += 1
    print(f"OK: scanned={scanned} injected={changed} root={root}")
    return 0


if __name__ == "__main__":
    raise SystemExit(main())