import logging
from apscheduler.schedulers.asyncio import AsyncIOScheduler
from apscheduler.triggers.interval import IntervalTrigger
from apscheduler.triggers.cron import CronTrigger

logger = logging.getLogger(__name__)

_scheduler = None
_is_running = False


def init_scheduler():
    """Initialize the APScheduler instance."""
    global _scheduler
    _scheduler = AsyncIOScheduler()
    logger.info("Scheduler initialized")


def start_scheduler(interval_minutes: int = 10):
    """Start the scheduler with the given interval."""
    global _is_running
    if _scheduler is None:
        init_scheduler()

    # Remove existing job if any
    if _scheduler.get_job("sync_job"):
        _scheduler.remove_job("sync_job")

    from . import sync_service

    _scheduler.add_job(
        sync_service.run_sync,
        trigger=IntervalTrigger(minutes=interval_minutes),
        id="sync_job",
        name="GoMag Sync",
        replace_existing=True
    )

    if not _scheduler.running:
        _scheduler.start()

    _is_running = True
    logger.info(f"Scheduler started with interval {interval_minutes}min")


def start_maintenance_job(hour: int = 3):
    """Schedule the daily DB/log maintenance job (prune history + cleanup logs).

    Runs independently of the sync job — starts the scheduler if it isn't already
    running so maintenance happens even when auto-sync is disabled.
    """
    if _scheduler is None:
        init_scheduler()

    from . import maintenance_service

    _scheduler.add_job(
        maintenance_service.run_daily_maintenance,
        trigger=CronTrigger(hour=hour, minute=0),
        id="maintenance_job",
        name="Daily DB/Log Maintenance",
        replace_existing=True
    )

    if not _scheduler.running:
        _scheduler.start()

    logger.info(f"Maintenance job scheduled daily at {hour:02d}:00")


def stop_scheduler():
    """Stop the scheduler."""
    global _is_running
    if _scheduler and _scheduler.running:
        if _scheduler.get_job("sync_job"):
            _scheduler.remove_job("sync_job")
        _is_running = False
        logger.info("Scheduler stopped")


def shutdown_scheduler():
    """Shutdown the scheduler completely."""
    global _scheduler, _is_running
    if _scheduler and _scheduler.running:
        _scheduler.shutdown(wait=False)
    _scheduler = None
    _is_running = False


def get_scheduler_status():
    """Get current scheduler status."""
    job = _scheduler.get_job("sync_job") if _scheduler else None
    return {
        "enabled": _is_running,
        "next_run": job.next_run_time.isoformat() if job and job.next_run_time else None,
        "interval_minutes": int(job.trigger.interval.total_seconds() / 60) if job else None
    }