import uuid

from sqlalchemy import select
from sqlalchemy.ext.asyncio import AsyncSession

from invite_utils import generate_invite_identifier
from models import Invite, InviteStatus, User


def unique_email(prefix: str = "test") -> str:
    """Generate a unique email for tests sharing the same database."""
    return f"{prefix}-{uuid.uuid4().hex[:8]}@example.com"


async def create_invite_for_godfather(db: AsyncSession, godfather_id: int) -> str:
    """
    Create an invite for an existing godfather user.

    Args:
        db: Database session
        godfather_id: ID of the existing user who will be the godfather

    Returns:
        The invite identifier.

    Raises:
        ValueError: If the godfather user doesn't exist.
    """
    # Verify godfather exists
    result = await db.execute(select(User).where(User.id == godfather_id))
    godfather = result.scalar_one_or_none()

    if not godfather:
        raise ValueError(f"Godfather user with ID {godfather_id} not found")

    # Create invite
    identifier = generate_invite_identifier()
    invite = Invite(
        identifier=identifier,
        godfather_id=godfather_id,
        status=InviteStatus.READY,
    )
    db.add(invite)
    await db.commit()

    return identifier


# Backwards-compatible alias that gets a user by email
async def create_invite_for_registration(db: AsyncSession, godfather_email: str) -> str:
    """
    Create an invite for an existing godfather user (looked up by email).

    The godfather must already exist in the database.

    Args:
        db: Database session
        godfather_email: Email of the existing user who will be the godfather

    Returns:
        The invite identifier.

    Raises:
        ValueError: If the godfather user doesn't exist.
    """
    result = await db.execute(select(User).where(User.email == godfather_email))
    godfather = result.scalar_one_or_none()

    if not godfather:
        raise ValueError(
            f"Godfather user with email '{godfather_email}' not found. "
            "Create the user first using create_user_with_roles()."
        )

    return await create_invite_for_godfather(db, godfather.id)