import secrets
from typing import Any

from sqlalchemy import select
from sqlalchemy.orm import Session

from app.auth.tokens import hash_token
from app.db.models import CharacterCard, User
from app.character.card import DEFAULT_CARD, normalize_card
import json


def find_user_by_token(db: Session, token: str) -> User | None:
    token_hash = hash_token(token.strip())
    return db.scalar(
        select(User).where(User.api_token_hash == token_hash, User.is_active.is_(True))
    )


def user_to_dict(user: User) -> dict[str, Any]:
    return {
        "id": user.id,
        "username": user.username,
        "display_name": user.display_name or user.username,
    }


def create_user(
    db: Session,
    *,
    username: str,
    display_name: str = "",
    api_token: str | None = None,
) -> tuple[User, str]:
    clean = username.strip().lower()
    if not clean:
        raise ValueError("username не может быть пустым")
    existing = db.scalar(select(User).where(User.username == clean))
    if existing:
        raise ValueError(f"Пользователь «{clean}» уже существует")

    plain_token = (api_token or "").strip() or secrets.token_urlsafe(32)
    user = User(
        username=clean,
        display_name=(display_name or clean).strip(),
        api_token_hash=hash_token(plain_token),
        is_active=True,
    )
    db.add(user)
    db.flush()

    card = normalize_card(DEFAULT_CARD)
    db.add(
        CharacterCard(
            user_id=user.id,
            card_json=json.dumps(card, ensure_ascii=False),
        )
    )
    db.commit()
    db.refresh(user)
    return user, plain_token