#!/usr/bin/env python3
"""提供健康检查，并验证平台重启容器后 /app 中的文件是否保留。"""

import json
import os
import socket
import sys
import threading
import time
from datetime import datetime, timezone
from http.server import BaseHTTPRequestHandler, ThreadingHTTPServer
from pathlib import Path


PORT = int(os.getenv("PORT", "8080"))
RUN_SECONDS = int(os.getenv("RUN_SECONDS", "60"))
MARKER = Path(os.getenv("MARKER_FILE", "/app/restart-marker.txt"))


class Handler(BaseHTTPRequestHandler):
    def do_GET(self) -> None:
        if self.path != "/health":
            self.send_error(404)
            return
        payload = json.dumps({"status": "ok"}).encode()
        self.send_response(200)
        self.send_header("Content-Type", "application/json")
        self.send_header("Content-Length", str(len(payload)))
        self.end_headers()
        self.wfile.write(payload)

    def log_message(self, _format: str, *_args: object) -> None:
        return


def main() -> int:
    now = datetime.now(timezone.utc).astimezone().isoformat()
    pod_name = os.getenv("POD_NAME", socket.gethostname())
    pod_uid = os.getenv("POD_UID", "unknown")
    existed = MARKER.exists()
    previous = MARKER.read_text().strip() if existed else "<missing>"

    print("=" * 70, flush=True)
    print(f"time={now}", flush=True)
    print(f"pod_name={pod_name}", flush=True)
    print(f"pod_uid={pod_uid}", flush=True)
    print(f"marker={MARKER}", flush=True)
    print(f"marker_existed_before_start={str(existed).lower()}", flush=True)
    print(f"marker_previous_content={previous}", flush=True)

    MARKER.parent.mkdir(parents=True, exist_ok=True)
    MARKER.write_text(f"pod={pod_name} uid={pod_uid} written_at={now}\n")
    print("marker_written=true", flush=True)

    server = ThreadingHTTPServer(("0.0.0.0", PORT), Handler)
    server_thread = threading.Thread(target=server.serve_forever, daemon=True)
    server_thread.start()
    print(f"health_url=http://0.0.0.0:{PORT}/health", flush=True)
    print(f"will_exit_normally_after={RUN_SECONDS}s", flush=True)
    time.sleep(RUN_SECONDS)
    server.shutdown()
    server.server_close()
    print("program completed; exiting normally with code 0", flush=True)
    return 0


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