# management/tasks.py
# -*- coding: utf-8 -*-
from __future__ import absolute_import, unicode_literals
import requests
import json
import os
import datetime
from celery import shared_task
from django.db import connections, connection
from django.conf import settings
from django.utils import timezone

from .models import (
    Panel,
    AdminLevel2,
    AdminLevel3,
    EndUser,
    Payment,
    CustomUser,
    Subscription,
)
from django.core.management import call_command

# --- Utilities ---
# FIXED: Renamed function to match imports in other files
@shared_task
def send_telegram_message(chat_id, message, bot_token):
    """
    Sends a message to a specific Telegram chat using a bot token.
    """
    if not bot_token:
        print("Telegram bot token is not configured.")
        return

    url = f"https://api.telegram.org/bot{bot_token}/sendMessage"
    payload = {
        "chat_id": chat_id,
        "text": message,
        "parse_mode": "Markdown"
    }
    
    try:
        response = requests.post(url, json=payload)
        response.raise_for_status()
        print(f"Notification sent successfully to chat_id {chat_id}")
    except requests.RequestException as e:
        print(f"Failed to send notification to chat_id {chat_id}: {e}")

# --- Celery Tasks ---
@shared_task(name="management.tasks.schedule_reminders")
def schedule_reminders():
    """
    Celery task to send periodic reminders to admins and users.
    """
    now = timezone.now().date()
    
    # 1. License expiry warnings for AdminLevel2s (resellers)
    three_days_from_now = now + datetime.timedelta(days=3)
    admin_level2s = AdminLevel2.objects.filter(license_expiry_date__lte=three_days_from_now)
    for admin in admin_level2s:
        # Assuming AdminLevel2 is linked to a Panel through its CustomUser owner
        # This part might need adjustment based on the final model structure
        try:
            panel = Panel.objects.get(owner=admin.user)
            if admin.telegram_chat_id and panel.telegram_bot_token:
                message = (
                    f"🚨 **هشدار انقضای لایسنس!**\n\n"
                    f"ادمین {admin.user.username}، لایسنس شما در تاریخ {admin.license_expiry_date} منقضی خواهد شد. لطفاً برای تمدید آن اقدام کنید."
                )
                send_telegram_message(
                    chat_id=admin.telegram_chat_id,
                    message=message,
                    bot_token=panel.telegram_bot_token
                )
        except Panel.DoesNotExist:
            print(f"Panel for admin {admin.user.username} not found.")


@shared_task
def send_payment_receipt_to_admin(payment_id):
    """
    Sends a payment receipt notification to the relevant admin via Telegram.
    """
    try:
        payment = Payment.objects.get(id=payment_id)
        admin = payment.admin
        panel = payment.subscription.panel

        if not admin.admin_level_3.telegram_chat_id or not panel.telegram_bot_token:
            print(f"Admin telegram_chat_id or bot token not found for payment {payment_id}.")
            return

        message = (
            f"🔔 **رسید پرداخت جدید!**\n\n"
            f"یک کاربر ({payment.subscription.end_user.username}) رسید پرداختی را برای تمدید اشتراک ارسال کرده است.\n"
            f"مبلغ: {payment.amount} تومان\n"
            f"توکن پرداخت: `{payment.payment_token}`\n"
            f"لطفا به پنل خود مراجعه کرده و پرداخت را تایید کنید."
        )

        if payment.receipt_image:
            message += f"\n\nتصویر رسید پرداخت آپلود شده است."
        elif payment.receipt_text:
             message += f"\n\nمتن رسید پرداخت: {payment.receipt_text}"
        
        send_telegram_message(
            chat_id=admin.admin_level_3.telegram_chat_id,
            message=message,
            bot_token=panel.telegram_bot_token
        )

    except Payment.DoesNotExist:
        print(f"Payment with id {payment_id} not found.")
    except Exception as e:
        print(f"Error sending payment receipt to admin: {e}")


@shared_task
def send_payment_confirmation_to_user(end_user_id, amount, status):
    """
    Sends a payment confirmation message to the end-user.
    """
    try:
        end_user = EndUser.objects.get(id=end_user_id)
        panel = end_user.panel
        
        if not panel or not panel.telegram_bot_token or not end_user.telegram_chat_id:
            print(f"EndUser panel, bot token or telegram_chat_id not found for user {end_user_id}.")
            return

        if status == 'approved':
            message = (
                f"✅ **پرداخت شما تأیید شد**\n\n"
                f"مبلغ {amount} تومان برای پنل {panel.name} با موفقیت تأیید شد. سرویس شما به زودی فعال خواهد شد."
            )
        else:
            message = (
                f"❌ **پرداخت شما رد شد**\n\n"
                f"پرداخت {amount} تومان برای پنل {panel.name} رد شد. لطفاً رسید معتبر را ارسال کنید."
            )

        send_telegram_message(
            chat_id=end_user.telegram_chat_id,
            message=message,
            bot_token=panel.telegram_bot_token
        )
    except EndUser.DoesNotExist:
        print(f"EndUser with id {end_user_id} not found.")
    except Exception as e:
        print(f"Error sending payment confirmation to user: {e}")

@shared_task(name="management.tasks.check_subscription_expiry")
def check_subscription_expiry():
    """
    Celery task to check subscription expiry and send notifications.
    """
    now = timezone.now().date()
    
    # Send reminder 3 days before expiry
    three_days_from_now = now + datetime.timedelta(days=3)
    expiring_soon_subscriptions = Subscription.objects.filter(
        end_date__date=three_days_from_now,
        status='active'
    )
    
    for sub in expiring_soon_subscriptions:
        if sub.end_user.telegram_chat_id and sub.panel.telegram_bot_token:
            message = (
                f"⏳ **اشتراک شما به زودی منقضی می‌شود!**\n\n"
                f"کاربر {sub.end_user.username}، اشتراک شما در تاریخ {sub.end_date.strftime('%Y-%m-%d')} منقضی خواهد شد. برای تمدید آن از طریق بات اقدام کنید."
            )
            send_telegram_message(
                chat_id=sub.end_user.telegram_chat_id,
                message=message,
                bot_token=sub.panel.telegram_bot_token
            )
            
    # Deactivate expired subscriptions
    expired_subscriptions = Subscription.objects.filter(end_date__lte=now, status='active')
    for sub in expired_subscriptions:
        sub.status = 'expired'
        sub.save()
        if sub.end_user.telegram_chat_id and sub.panel.telegram_bot_token:
            message = (
                f"❌ **اشتراک شما منقضی شد!**\n\n"
                f"کاربر {sub.end_user.username}، اشتراک شما منقضی شده است. لطفا برای تمدید اقدام کنید."
            )
            send_telegram_message(
                chat_id=sub.end_user.telegram_chat_id,
                message=message,
                bot_token=sub.panel.telegram_bot_token
            )