import json
import os
import socket
import time
from urllib.error import HTTPError, URLError
from urllib.request import Request, urlopen


NODE_NAME = os.getenv("NODE_NAME") or socket.gethostname()
ORCHESTRATOR_URL = os.getenv("ORCHESTRATOR_URL")
SERVICES_TO_CHECK = {
    name.strip()
    for name in os.getenv("SERVICES_TO_CHECK", "").split(",")
    if name.strip()
}
INTERVAL_SECONDS = int(os.getenv("INTERVAL_SECONDS", "30"))
SERVICE_CATALOG = [
    {"name": "homeassistant", "type": "http", "url": "http://homeassistant:8123"},
    {"name": "lms", "type": "tcp", "host": "192.168.31.6", "port": 9000},
    {"name": "forgejo", "type": "http", "url": "http://forgejo:3000"},
    {"name": "nginx", "type": "http", "url": "http://nginx"},
    {"name": "mosquitto", "type": "tcp", "host": "mosquitto", "port": 1883},
]


def services_to_check():
    if not SERVICES_TO_CHECK:
        return SERVICE_CATALOG
    return [
        service for service in SERVICE_CATALOG
        if service["name"] in SERVICES_TO_CHECK
    ]


def check_http(url):
    request = Request(url, headers={"User-Agent": "monitor-agent/1.0"})
    try:
        with urlopen(request, timeout=5) as response:
            return "ok" if response.status == 200 else "error"
    except (HTTPError, URLError, TimeoutError, OSError):
        return "error"


def check_tcp(host, port):
    try:
        with socket.create_connection((host, int(port)), timeout=5):
            return "ok"
    except OSError:
        return "error"


def check_service(service):
    service_type = service.get("type")
    if service_type == "http":
        return check_http(service["url"])
    if service_type == "tcp":
        return check_tcp(service["host"], service["port"])
    return "error"


def build_event(service, status):
    return {
        "type": "health",
        "service": service["name"],
        "status": status,
        "timestamp": time.time(),
        "run_id": None,
        "node": NODE_NAME,
    }


def send_event(event):
    body = json.dumps(event).encode("utf-8")
    request = Request(
        ORCHESTRATOR_URL,
        data=body,
        headers={"Content-Type": "application/json"},
        method="POST",
    )
    with urlopen(request, timeout=5) as response:
        if response.status >= 300:
            raise RuntimeError(f"event endpoint returned {response.status}")


def main():
    if not ORCHESTRATOR_URL:
        raise SystemExit("ORCHESTRATOR_URL is required")

    selected_services = services_to_check()
    print(
        (
            f"[monitor-agent] ready node={NODE_NAME} "
            f"url={ORCHESTRATOR_URL} "
            f"services={[service['name'] for service in selected_services]}"
        ),
        flush=True,
    )

    while True:
        started = time.time()
        for service in selected_services:
            status = check_service(service)
            event = build_event(service, status)
            try:
                send_event(event)
            except Exception as exc:
                print(f"[monitor-agent] send failed: {exc}", flush=True)
            print(json.dumps(event), flush=True)

        elapsed = time.time() - started
        time.sleep(max(0, INTERVAL_SECONDS - elapsed))


if __name__ == "__main__":
    main()

print("MONITOR_AGENT_VERSION=1")