"""FastAPI-зависимости: аутентификация по API-ключу."""

from __future__ import annotations

import hashlib

from fastapi import Depends, HTTPException, status
from fastapi.security import HTTPAuthorizationCredentials, HTTPBearer
from sqlalchemy import select
from sqlalchemy.ext.asyncio import AsyncSession

from app.database import get_db
from app.models import User

security_scheme = HTTPBearer(auto_error=False)


def hash_api_key(api_key: str) -> str:
    return hashlib.sha256(api_key.encode()).hexdigest()


async def get_current_user_from_header(
    credentials: HTTPAuthorizationCredentials | None = Depends(security_scheme),
    db: AsyncSession = Depends(get_db),
) -> User:
    """Аутентификация по заголовку Authorization: Bearer <api_key>."""
    if credentials is None:
        raise HTTPException(
            status_code=status.HTTP_401_UNAUTHORIZED,
            detail="Missing Authorization header. Use: Authorization: Bearer <api_key>",
        )

    api_key = credentials.credentials
    if not api_key.startswith("md2vk_"):
        raise HTTPException(
            status_code=status.HTTP_401_UNAUTHORIZED,
            detail="Invalid API key format",
        )

    api_key_hash = hash_api_key(api_key)
    result = await db.execute(
        select(User).where(User.api_key_hash == api_key_hash, User.is_active == True)
    )
    user = result.scalar_one_or_none()
    if user is None:
        raise HTTPException(status_code=status.HTTP_401_UNAUTHORIZED, detail="Invalid API key")

    return user


async def get_user_by_api_key(api_key: str, db: AsyncSession) -> User:
    """Проверяет API-ключ из тела запроса. Используется в POST-эндпоинтах."""
    if not api_key.startswith("md2vk_"):
        raise HTTPException(status_code=401, detail="Invalid API key format")

    api_key_hash = hash_api_key(api_key)
    result = await db.execute(
        select(User).where(User.api_key_hash == api_key_hash, User.is_active == True)
    )
    user = result.scalar_one_or_none()
    if user is None:
        raise HTTPException(status_code=401, detail="Invalid API key")

    return user