#!/usr/bin/env python3
"""Check S91 CTO SOT dotpath migration state."""

from __future__ import annotations

import os
import re
from pathlib import Path

ROOT = Path(__file__).resolve().parents[1]
REQUIRED_FILES = [
    ".sot/00-START/CTO-WORKSPACE-INTENT.md",
    ".sot/03-PROTOCOLS/CTO-CASE-BACKEND-BRIEF.md",
    ".sot/03-PROTOCOLS/CTO-CASE-PROVIDER-DECISION-RECORD.md",
]
SCAN_FILES = [
    "AGENTS.md",
    "README.md",
    "WORKBOARD.yaml",
    "tools/validate_cto_child.py",
]


def fail(message: str) -> None:
    raise SystemExit(f"S91 cto dotpath check failed: {message}")


def main() -> int:
    if not (ROOT / ".sot").is_dir():
        fail("missing canonical .sot directory")
    legacy = ROOT / "sot"
    if not legacy.is_symlink():
        fail("legacy sot path must be a temporary symlink")
    if os.readlink(legacy) != ".sot":
        fail("legacy sot symlink must target .sot")

    for relative in REQUIRED_FILES:
        if not (ROOT / relative).is_file():
            fail(f"missing required canonical file: {relative}")

    for relative in SCAN_FILES:
        text = (ROOT / relative).read_text(encoding="utf-8")
        if re.search(r"(?<!\.)sot/", text):
            fail(f"legacy sot reference remains in {relative}")
        if ".sot/" not in text:
            fail(f"missing canonical .sot reference in {relative}")

    for path in (ROOT / ".sot").rglob("*.md"):
        text = path.read_text(encoding="utf-8")
        if re.search(r"source:\s+sot/", text):
            fail(f"legacy source frontmatter remains in {path.relative_to(ROOT)}")

    print("S91 cto dotpath check passed")
    return 0


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