#!/usr/bin/env python3
"""Fail when a page under docs/ is missing from mkdocs.yml's nav.

docs/ is the source of truth (CLAUDE.md §12), but only the pages listed in the nav
are published — and mkdocs' own `omitted_files: warn` keeps a build green while
silently dropping them, which is how every ADR after 0010 and every runbook but
ci.md fell off the site.

ponytail: a substring test, not a YAML parse — a page's path either appears in
mkdocs.yml or it doesn't, and that needs no dependency.
"""

import sys
from pathlib import Path

ROOT = Path(__file__).resolve().parents[1]
nav = (ROOT / "mkdocs.yml").read_text()

missing = sorted(
    str(page.relative_to(ROOT / "docs"))
    for page in (ROOT / "docs").rglob("*.md")
    if str(page.relative_to(ROOT / "docs")) not in nav
)

if missing:
    print(f"{len(missing)} page(s) under docs/ are not in mkdocs.yml's nav:")
    print("\n".join(f"  {m}" for m in missing))
    sys.exit(1)

print("docs nav complete: every page under docs/ is published")