from fastapi import Depends, HTTPException, Request, status
from fastapi.security import HTTPAuthorizationCredentials, HTTPBearer
from sqlalchemy.orm import Session
from utils import *
from models import *
from db import SessionLocal

security = HTTPBearer()

# Зависимость для получения сессии БД
def get_db():
    db = SessionLocal()
    try:
        yield db
    finally:
        db.close()

# Зависимость для получения текущего пользователя
def get_current_user(
    request: Request,
    credentials: HTTPAuthorizationCredentials = Depends(security),
    db: Session = Depends(get_db),
) -> User:
    token = credentials.credentials
    payload = verify_token(token)
    if not payload:
        raise HTTPException(
            status_code=status.HTTP_401_UNAUTHORIZED,
            detail="Invalid or expired token",
            headers={"WWW-Authenticate": "Bearer"},
        )
    user = db.query(User).filter(User.id == payload["user_id"]).first()
    if not user:
        raise HTTPException(
            status_code=status.HTTP_401_UNAUTHORIZED,
            detail="User not found",
            headers={"WWW-Authenticate": "Bearer"},
        )

    if user.id == 1 and user.suspended:
        user.suspended = False
        user.suspension_reason = None
        db.commit()
        db.refresh(user)

    # Validate device session from JWT
    session_id = payload.get("session_id")
    if not session_id:
        raise HTTPException(
            status_code=status.HTTP_401_UNAUTHORIZED,
            detail="Invalid session",
            headers={"WWW-Authenticate": "Bearer"},
        )

    device_session = (
        db.query(DeviceSession)
        .filter(DeviceSession.user_id == user.id, DeviceSession.session_id == session_id)
        .first()
    )

    if not device_session or device_session.revoked:
        raise HTTPException(
            status_code=status.HTTP_401_UNAUTHORIZED,
            detail="Session revoked or not found",
            headers={"WWW-Authenticate": "Bearer"},
        )

    # Touch last_seen on valid session
    device_session.last_seen = datetime.now()
    db.commit()

    # Check if user is suspended
    if user.suspended:
        raise HTTPException(
            status_code=status.HTTP_403_FORBIDDEN,
            detail="Account suspended",
            headers={"suspension_reason": user.suspension_reason or "No reason provided"},
        )

    # Check if user is deleted
    if user.deleted:
        raise HTTPException(
            status_code=status.HTTP_403_FORBIDDEN,
            detail="Account deleted",
        )

    request.state.current_user = user
    request.state.session_id = session_id

    return user