import socket
import time
from datetime import datetime, timezone
from urllib.request import urlopen

from app.config import settings
from app.models import CheckResult, HealthResponse, RuntimeResponse
from app.services.systemd_manager import SystemdManager

START_TIME = time.time()
HEALTH_TARGETS = {
    'backend': 'http://127.0.0.1:8000/health',
    'worker': None,
    'frontend': 'http://127.0.0.1:5173/',
}


def probe_http(url: str | None) -> CheckResult:
    if not url:
        return CheckResult(status='warn', detail='no health endpoint configured')
    try:
        started = time.time()
        with urlopen(url, timeout=2) as resp:
            latency = round((time.time() - started) * 1000, 2)
            return CheckResult(status='pass' if resp.status < 400 else 'fail', latency_ms=latency, detail=f'HTTP {resp.status}')
    except Exception as exc:
        return CheckResult(status='fail', detail=str(exc))


def build_health() -> HealthResponse:
    return HealthResponse(
        status='pass',
        service=settings.service_name,
        version=settings.version,
        time=datetime.now(timezone.utc),
        uptime_s=round(time.time() - START_TIME, 2),
        checks={'dbus': CheckResult(status='pass', detail='system bus reachable')},
    )


def build_runtime(systemd_manager: SystemdManager) -> RuntimeResponse:
    services = systemd_manager.list_services(settings.monitored_services)
    checks = {'dbus': CheckResult(status='pass', detail='system bus reachable')}
    checks.update({k: probe_http(v) for k, v in HEALTH_TARGETS.items()})
    overall = 'pass'
    if any(c.status == 'fail' for c in checks.values()) or any(s.status == 'fail' for s in services):
        overall = 'fail'
    elif any(c.status == 'warn' for c in checks.values()) or any(s.status == 'warn' for s in services):
        overall = 'warn'
    return RuntimeResponse(
        status=overall,
        service=settings.service_name,
        version=settings.version,
        time=datetime.now(timezone.utc),
        hostname=socket.gethostname(),
        uptime_s=round(time.time() - START_TIME, 2),
        services=services,
        checks=checks,
    )