"""Google Calendar integration service."""
from datetime import datetime
from typing import Optional

from google.auth.transport.requests import Request
from google.oauth2.credentials import Credentials
from googleapiclient.discovery import build
from sqlalchemy.orm import Session

from app.core.config import settings
from app.models.booking import Booking
from app.models.google_calendar_token import GoogleCalendarToken


def get_google_calendar_service(db: Session, user_id: int):
    """
    Get authenticated Google Calendar service for user.

    Args:
        db: Database session
        user_id: User ID

    Returns:
        Google Calendar service object or None if not connected
    """
    token_record = (
        db.query(GoogleCalendarToken)
        .filter(GoogleCalendarToken.user_id == user_id)
        .first()
    )

    if not token_record:
        return None

    # Create credentials
    creds = Credentials(
        token=token_record.access_token,
        refresh_token=token_record.refresh_token,
        token_uri="https://oauth2.googleapis.com/token",
        client_id=settings.google_client_id,
        client_secret=settings.google_client_secret,
    )

    # Refresh if expired
    if creds.expired and creds.refresh_token:
        try:
            creds.refresh(Request())

            # Update tokens in DB
            token_record.access_token = creds.token  # type: ignore[assignment]
            if creds.expiry:
                token_record.token_expiry = creds.expiry  # type: ignore[assignment]
            db.commit()
        except Exception as e:
            print(f"Failed to refresh Google token: {e}")
            return None

    # Build service
    try:
        service = build("calendar", "v3", credentials=creds)
        return service
    except Exception as e:
        print(f"Failed to build Google Calendar service: {e}")
        return None


def create_calendar_event(
    db: Session, booking: Booking, user_id: int
) -> Optional[str]:
    """
    Create Google Calendar event for booking.

    Args:
        db: Database session
        booking: Booking object
        user_id: User ID

    Returns:
        Google Calendar event ID or None if failed
    """
    try:
        service = get_google_calendar_service(db, user_id)
        if not service:
            return None

        # Create event
        event = {
            "summary": f"{booking.space.name}: {booking.title}",
            "description": booking.description or "",
            "start": {
                "dateTime": booking.start_datetime.isoformat(),  # type: ignore[union-attr]
                "timeZone": "UTC",
            },
            "end": {
                "dateTime": booking.end_datetime.isoformat(),  # type: ignore[union-attr]
                "timeZone": "UTC",
            },
        }

        created_event = service.events().insert(calendarId="primary", body=event).execute()

        return created_event.get("id")
    except Exception as e:
        print(f"Failed to create Google Calendar event: {e}")
        return None


def update_calendar_event(
    db: Session, booking: Booking, user_id: int, event_id: str
) -> bool:
    """
    Update Google Calendar event for booking.

    Args:
        db: Database session
        booking: Booking object
        user_id: User ID
        event_id: Google Calendar event ID

    Returns:
        True if successful, False otherwise
    """
    try:
        service = get_google_calendar_service(db, user_id)
        if not service:
            return False

        # Update event
        event = {
            "summary": f"{booking.space.name}: {booking.title}",
            "description": booking.description or "",
            "start": {
                "dateTime": booking.start_datetime.isoformat(),  # type: ignore[union-attr]
                "timeZone": "UTC",
            },
            "end": {
                "dateTime": booking.end_datetime.isoformat(),  # type: ignore[union-attr]
                "timeZone": "UTC",
            },
        }

        service.events().update(
            calendarId="primary", eventId=event_id, body=event
        ).execute()

        return True
    except Exception as e:
        print(f"Failed to update Google Calendar event: {e}")
        return False


def delete_calendar_event(db: Session, event_id: str, user_id: int) -> bool:
    """
    Delete Google Calendar event.

    Args:
        db: Database session
        event_id: Google Calendar event ID
        user_id: User ID

    Returns:
        True if successful, False otherwise
    """
    try:
        service = get_google_calendar_service(db, user_id)
        if not service:
            return False

        service.events().delete(calendarId="primary", eventId=event_id).execute()
        return True
    except Exception as e:
        print(f"Failed to delete Google Calendar event: {e}")
        return False