"""验证就绪探针:数据库不可用时 /health/ready 返回 503 而非 200。

运行方式(在宿主机上):
  python tests/test_health_ready.py

脚本经本地 8000 端口直调 API,通过启停 postgres 容器验证:
  - 健康时返回 HTTP 200
  - postgres 停止后返回 HTTP 503(不再误报 200)
  - postgres 恢复后回到 200
"""
from __future__ import annotations

import json
import subprocess
import sys
import time
import urllib.request


BASE = "http://localhost:8000"


def api_status() -> tuple[int, dict]:
    try:
        with urllib.request.urlopen(f"{BASE}/health/ready", timeout=5) as r:
            return r.status, json.loads(r.read())
    except urllib.error.HTTPError as e:
        return e.code, json.loads(e.read())


def compose(*args: str) -> None:
    subprocess.run(["docker", "compose", *args], check=False, capture_output=True)


def wait_for(target: int, timeout: int = 30) -> bool:
    deadline = time.time() + timeout
    while time.time() < deadline:
        try:
            code, _ = api_status()
            if code == target:
                return True
        except Exception:
            pass
        time.sleep(1)
    return False


def main() -> int:
    code, _ = api_status()
    if code != 200:
        print(f"FAIL: 初始状态期望 200,得到 {code}"); return 1
    print(f"PASS: 健康时 HTTP 200")

    compose("stop", "postgres")
    try:
        if not wait_for(503, timeout=30):
            print("FAIL: postgres 停止后未返回 503"); return 1
        print("PASS: postgres 停止后 HTTP 503(就绪探针正确拒绝)")
    finally:
        compose("start", "postgres")

    if not wait_for(200, timeout=30):
        print("FAIL: postgres 恢复后未回到 200"); return 1
    print("PASS: postgres 恢复后 HTTP 200")

    print("ALL PASS")
    return 0


if __name__ == "__main__":
    sys.exit(main())