"""§17 health-check endpoint source.

A small unauthenticated probe used by ops tooling (e.g. the flotilla
deploy control panel) to verify a deploy landed correctly. The
structural value is the version-match check — after `systemctl
restart` reports active, the operator polls `/api/health` and
verifies the returned `version` equals the tag just deployed,
catching the failure mode where a restart did not pick up the new
code.

The version is read from the `VERSION` file at the repo root at
import time (§20.1's canonical source) and cached as a module-level
constant. A missing `VERSION` fails loudly per §20.6 rather than
serving a placeholder — a silent default would defeat the
version-match check that is the entire point of the endpoint.

`status` is always `"ok"` (HTTP 200) in v1. The `"degraded"` / 503
path stays in the response shape so a later release can wire real
degradation conditions (reconciler stuck, migrations pending,
provider universe empty) without breaking the contract.
"""
from __future__ import annotations

from pathlib import Path


_VERSION_PATH = Path(__file__).resolve().parents[2] / "VERSION"


def _read_version() -> str:
    text = _VERSION_PATH.read_text(encoding="utf-8").strip()
    if not text:
        raise RuntimeError(f"VERSION file at {_VERSION_PATH} is empty")
    return text


VERSION: str = _read_version()