from apscheduler.schedulers.background import BackgroundScheduler
from apscheduler.triggers.cron import CronTrigger

from db import PostScheduler

# =========================
# Flask app (будет установлен из app.py)
# =========================
flask_app = None

# =========================
# Scheduler
# =========================
scheduler: BackgroundScheduler | None = None
JOB_ID = "vk_publish_job"


def clearLog():
    from collections import deque
    from config import Config

    with open(Config.LOG_FILE, "r", encoding="utf-8") as f:
        last_lines = deque(f, maxlen=500)

    with open(Config.LOG_FILE, "w", encoding="utf-8") as f:
        f.writelines(last_lines)


def init_scheduler(app):
    """
    Инициализация планировщика с Flask-приложением
    Вызывать ОДИН раз при старте приложения
    """
    global flask_app, scheduler

    flask_app = app

    if scheduler is None:
        scheduler = BackgroundScheduler()
        trigger = CronTrigger(hour=0, minute=0)
        scheduler.add_job(
            clearLog, trigger=trigger, id="clear_log_job", replace_existing=True
        )
        scheduler.start()


# =========================
# JOB wrapper
# =========================
def vk_publish_job():
    """
    Обёртка для APScheduler
    """
    if flask_app is None:
        raise RuntimeError("Scheduler is not initialized with Flask app")

    from vk_handler import handle_vk_post

    with flask_app.app_context():
        handle_vk_post()


# =========================
# Enable job
# =========================
def enable_publish_job():
    """
    Включает выполнение публикации постов
    """
    if not scheduler:
        return

    scheduleData = PostScheduler.query.first()
    if not scheduleData or not scheduleData.enabled:
        disable_publish_job()
        return

    trigger = CronTrigger(
        hour=f"{scheduleData.hour}",
        minute=f"{scheduleData.minute}",
        day="*",
    )

    scheduler.add_job(
        vk_publish_job,
        trigger=trigger,
        id=JOB_ID,
        replace_existing=True,
    )


# =========================
# Disable job
# =========================
def disable_publish_job():
    if scheduler and scheduler.get_job(JOB_ID):
        scheduler.remove_job(JOB_ID)


# =========================
# Status
# =========================
def get_scheduler_status() -> dict:
    scheduler_running = bool(scheduler and scheduler.running)
    job = scheduler.get_job(JOB_ID) if scheduler_running else None

    return {
        "scheduler": scheduler_running,
        "vk_publish_job": job is not None,
        "next_run_time": (
            job.next_run_time.strftime("%Y-%m-%d %H:%M:%S")
            if job and job.next_run_time
            else None
        ),
    }