"""
Background tasks for Castle accounting extension.
These tasks handle automated reconciliation checks and maintenance.
"""

import asyncio
from datetime import datetime
from typing import Optional

from lnbits.tasks import register_invoice_listener

from .crud import check_balance_assertion, get_balance_assertions
from .models import AssertionStatus


async def check_all_balance_assertions() -> dict:
    """
    Check all balance assertions and return results.
    This can be called manually or scheduled to run daily.

    Returns:
        dict: Summary of check results
    """
    from lnbits.helpers import urlsafe_short_hash

    # Get all assertions
    all_assertions = await get_balance_assertions(limit=1000)

    results = {
        "task_id": urlsafe_short_hash(),
        "timestamp": datetime.now().isoformat(),
        "total": len(all_assertions),
        "checked": 0,
        "passed": 0,
        "failed": 0,
        "errors": 0,
        "failed_assertions": [],
    }

    for assertion in all_assertions:
        try:
            checked = await check_balance_assertion(assertion.id)
            results["checked"] += 1

            if checked.status == AssertionStatus.PASSED:
                results["passed"] += 1
            elif checked.status == AssertionStatus.FAILED:
                results["failed"] += 1
                results["failed_assertions"].append({
                    "id": assertion.id,
                    "account_id": assertion.account_id,
                    "expected_sats": assertion.expected_balance_sats,
                    "actual_sats": checked.checked_balance_sats,
                    "difference_sats": checked.difference_sats,
                })
        except Exception as e:
            results["errors"] += 1
            print(f"Error checking assertion {assertion.id}: {e}")

    # Log results
    if results["failed"] > 0:
        print(f"[CASTLE] Daily reconciliation check: {results['failed']} FAILED assertions!")
        for failed in results["failed_assertions"]:
            print(f"  - Account {failed['account_id']}: expected {failed['expected_sats']}, got {failed['actual_sats']}")
    else:
        print(f"[CASTLE] Daily reconciliation check: All {results['passed']} assertions passed ✓")

    return results


async def scheduled_daily_reconciliation():
    """
    Scheduled task that runs daily to check all balance assertions.

    This function is meant to be called by a scheduler (cron, systemd timer, etc.)
    or by LNbits background task system.
    """
    print(f"[CASTLE] Running scheduled daily reconciliation check at {datetime.now()}")

    try:
        results = await check_all_balance_assertions()

        # TODO: Send notifications if there are failures
        # This could send email, webhook, or in-app notification
        if results["failed"] > 0:
            print(f"[CASTLE] WARNING: {results['failed']} balance assertions failed!")
            # Future: Send alert notification

        return results
    except Exception as e:
        print(f"[CASTLE] Error in scheduled reconciliation: {e}")
        raise


def start_daily_reconciliation_task():
    """
    Initialize the daily reconciliation task.

    This can be called from the extension's __init__.py or configured
    to run via external cron job.

    For cron setup:
    # Run daily at 2 AM
    0 2 * * * curl -X POST http://localhost:5000/castle/api/v1/tasks/daily-reconciliation -H "X-Api-Key: YOUR_ADMIN_KEY"
    """
    print("[CASTLE] Daily reconciliation task registered")
    # In a production system, you would register this with LNbits task scheduler
    # For now, it can be triggered manually via API endpoint