import asyncio
from apscheduler.schedulers.asyncio import AsyncIOScheduler
from apscheduler.triggers.cron import CronTrigger
from apscheduler.triggers.interval import IntervalTrigger
from backend.config import get_setting, load_settings
from backend.backup import run_backup_task
from backend.system import check_upgradable_packages
from backend.notifier import send_notification

scheduler = AsyncIOScheduler()

async def scheduled_backup_job():
    print("[SCHEDULER] Triggering scheduled automated backup...")
    settings = load_settings()
    scope = settings.get("scheduled_backup_scope", "pangolin")
    
    try:
        res = await run_backup_task(
            scope=scope,
            description="Automated scheduled backup",
            auto_created=True
        )
        if settings.get("notify_on_backup"):
            await send_notification(
                title=f"Automated Backup Started ({scope.upper()})",
                message=f"A scheduled backup job has been initiated.",
                status="info"
            )
    except Exception as e:
        print(f"[SCHEDULER] Error during scheduled backup: {e}")
        if settings.get("notify_on_backup"):
            await send_notification(
                title="Automated Backup Failed",
                message=f"Scheduled backup failed to start: {str(e)}",
                status="error"
            )

async def scheduled_update_check_job():
    print("[SCHEDULER] Checking for available updates...")
    settings = load_settings()
    if not settings.get("scheduled_update_check_enabled", True):
        return

    try:
        pkgs = await check_upgradable_packages()
        total = pkgs.get("total", 0)
        sec = pkgs.get("security_count", 0)

        if total > 0 and settings.get("notify_on_update"):
            await send_notification(
                title=f"📦 VPS Updates Available ({total} packages)",
                message=f"There are {total} upgradable package(s) available, including {sec} security update(s).",
                status="warning" if sec > 0 else "info",
                details={
                    "total_upgrades": total,
                    "security_updates": sec
                }
            )
    except Exception as e:
        print(f"[SCHEDULER] Error during update check: {e}")

def reload_scheduler():
    settings = load_settings()
    
    # Remove existing jobs if any
    for job_id in ["scheduled_backup", "scheduled_update_check"]:
        if scheduler.get_job(job_id):
            scheduler.remove_job(job_id)

    # 1. Scheduled Backup
    if settings.get("scheduled_backup_enabled", True):
        cron_expr = settings.get("scheduled_backup_cron", "0 3 * * *")
        parts = cron_expr.strip().split()
        if len(parts) == 5:
            trigger = CronTrigger(
                minute=parts[0],
                hour=parts[1],
                day=parts[2],
                month=parts[3],
                day_of_week=parts[4]
            )
            scheduler.add_job(
                scheduled_backup_job,
                trigger=trigger,
                id="scheduled_backup",
                replace_existing=True
            )
            print(f"[SCHEDULER] Scheduled backup registered with cron: {cron_expr}")

    # 2. Scheduled Update Check (every 12 hours)
    if settings.get("scheduled_update_check_enabled", True):
        scheduler.add_job(
            scheduled_update_check_job,
            trigger=IntervalTrigger(hours=12),
            id="scheduled_update_check",
            replace_existing=True
        )
        print("[SCHEDULER] Scheduled update checks registered (every 12 hours).")

def start_scheduler():
    if not scheduler.running:
        reload_scheduler()
        scheduler.start()
        print("[SCHEDULER] Scheduler started.")

def shutdown_scheduler():
    if scheduler.running:
        scheduler.shutdown()