from fastapi import Depends, HTTPException, status
from jose import jwt
from pydantic import ValidationError
from sqlalchemy.orm import Session

from app.core.config import settings
from app.core.security import oauth2_scheme
from app.db.session import get_db
from app.models.user import User
from app.schemas.token import TokenPayload


def get_current_user(
    db: Session = Depends(get_db), token: str = Depends(oauth2_scheme)
) -> User:
    """
    Get current user from token.
    """
    try:
        payload = jwt.decode(
            token, settings.JWT_SECRET_KEY, algorithms=[settings.JWT_ALGORITHM]
        )
        token_data = TokenPayload(**payload)
    except (jwt.JWTError, ValidationError):
        raise HTTPException(
            status_code=status.HTTP_403_FORBIDDEN,
            detail="Could not validate credentials",
        )
    
    user = db.query(User).filter(User.id == token_data.sub).first()
    if not user:
        raise HTTPException(status_code=404, detail="User not found")
    if not user.is_active:
        raise HTTPException(status_code=400, detail="Inactive user")
    
    return user


def get_current_active_user(
    current_user: User = Depends(get_current_user),
) -> User:
    """
    Get current active user.
    """
    if not current_user.is_active:
        raise HTTPException(status_code=400, detail="Inactive user")
    return current_user


def get_current_active_admin(
    current_user: User = Depends(get_current_user),
) -> User:
    """
    Get current active admin user.
    """
    if not current_user.is_active:
        raise HTTPException(status_code=400, detail="Inactive user")
    if not current_user.is_admin:
        raise HTTPException(
            status_code=403, detail="The user doesn't have enough privileges"
        )
    return current_user