"""
주기적으로 실행되는 모니터링 작업
- Pod 상태 체크 (1분마다)   → Discord + Gmail
- 인증서 만료 임박 체크 (1일마다) → Gmail만
"""
import os
import asyncio
from datetime import datetime, timezone
from apscheduler.schedulers.asyncio import AsyncIOScheduler
from notifier import notify_both, notify_email_only

NAMESPACE       = os.getenv("NAMESPACE", "web-portal")
ALERT_CERT_DAYS = int(os.getenv("ALERT_CERT_DAYS", "30"))

# 중복 알림 방지 캐시
_alerted_pods  = set()
_alerted_certs = set()

# ── K8s 클라이언트 ────────────────────────────────────────
def get_k8s_clients():
    try:
        from kubernetes import client, config
        try:
            config.load_incluster_config()
        except Exception:
            config.load_kube_config()
        return client.CoreV1Api(), client.CustomObjectsApi()
    except Exception as e:
        print(f"[MONITOR] K8s client init failed: {e}")
        return None, None

# ── Pod 모니터링 → Discord + Gmail ───────────────────────
async def check_pods():
    v1, _ = get_k8s_clients()
    if not v1:
        return
    try:
        pods = v1.list_namespaced_pod(namespace=NAMESPACE)
        for pod in pods.items:
            name   = pod.metadata.name
            phase  = pod.status.phase
            reason = ""

            if pod.status.container_statuses:
                for cs in pod.status.container_statuses:
                    if cs.state.waiting and cs.state.waiting.reason:
                        reason = cs.state.waiting.reason
                    if cs.restart_count and cs.restart_count >= 5:
                        reason = f"RestartCount={cs.restart_count}"

            is_unhealthy = (
                phase in ("Failed", "Unknown") or
                reason in ("CrashLoopBackOff", "OOMKilled", "Error", "ImagePullBackOff")
            )

            if is_unhealthy and name not in _alerted_pods:
                _alerted_pods.add(name)
                await notify_both(
                    title="🚨 Pod 이상 감지",
                    message=(
                        f"네임스페이스: `{NAMESPACE}`\n"
                        f"Pod: `{name}`\n"
                        f"상태: `{phase}`\n"
                        f"원인: `{reason or '알 수 없음'}`\n\n"
                        f"즉시 확인이 필요합니다."
                    ),
                    color=0xe74c3c
                )
            elif not is_unhealthy and name in _alerted_pods:
                _alerted_pods.discard(name)
                await notify_both(
                    title="✅ Pod 복구됨",
                    message=(
                        f"네임스페이스: `{NAMESPACE}`\n"
                        f"Pod: `{name}` 이 정상 상태로 복구되었습니다."
                    ),
                    color=0x2ecc71
                )
    except Exception as e:
        print(f"[MONITOR] Pod check error: {e}")

# ── 인증서 만료 모니터링 → Gmail만 ───────────────────────
async def check_certificates():
    _, custom = get_k8s_clients()
    if not custom:
        return
    try:
        namespaces = ["web-portal", "gitea", "argocd"]
        for ns in namespaces:
            try:
                certs = custom.list_namespaced_custom_object(
                    group="cert-manager.io",
                    version="v1",
                    namespace=ns,
                    plural="certificates"
                )
                for cert in certs.get("items", []):
                    name      = cert["metadata"]["name"]
                    not_after = cert.get("status", {}).get("notAfter", "")
                    if not not_after:
                        continue

                    expiry    = datetime.fromisoformat(not_after.replace("Z", "+00:00"))
                    now       = datetime.now(timezone.utc)
                    days_left = (expiry - now).days
                    alert_key = f"{ns}/{name}"

                    if days_left <= ALERT_CERT_DAYS and alert_key not in _alerted_certs:
                        _alerted_certs.add(alert_key)
                        await notify_email_only(
                            title="⚠️ 인증서 만료 임박",
                            message=(
                                f"네임스페이스: `{ns}`\n"
                                f"인증서: `{name}`\n"
                                f"만료까지: `{days_left}일 남음`\n"
                                f"만료일: `{expiry.strftime('%Y-%m-%d')}`\n\n"
                                f"cert-manager가 자동 갱신을 시도합니다.\n"
                                f"갱신 실패 시 수동으로 확인하세요."
                            ),
                            color=0xf39c12
                        )
                    elif days_left > ALERT_CERT_DAYS and alert_key in _alerted_certs:
                        _alerted_certs.discard(alert_key)
            except Exception:
                pass
    except Exception as e:
        print(f"[MONITOR] Certificate check error: {e}")

# ── 스케줄러 시작 ─────────────────────────────────────────
def start_scheduler():
    scheduler = AsyncIOScheduler()
    scheduler.add_job(check_pods,         "interval", minutes=1, id="pod_check")
    scheduler.add_job(check_certificates, "interval", hours=24,  id="cert_check")
    scheduler.start()
    print("[MONITOR] Scheduler started (Pod: 1min / Cert: 24hr)")
    return scheduler