import bcrypt
from jose import jwt, JWTError
from datetime import datetime, timedelta
from fastapi import HTTPException, status
import os

# Secret and algorithm for JWT
SECRET_KEY = os.getenv('SECRET_KEY', 'your_jwt_secret_key')  # Ensure this is set in your environment
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30

# Hash password using bcrypt directly
def get_password_hash(password: str) -> str:
    """Hashes the password using bcrypt."""
    salt = bcrypt.gensalt()  # Generate a salt
    hashed_password = bcrypt.hashpw(password.encode('utf-8'), salt)  # Hash the password
    return hashed_password.decode('utf-8')  # Return as a string

# Verify password using bcrypt directly
def verify_password(plain_password: str, hashed_password: str) -> bool:
    """Verifies if the plain password matches the hashed password."""
    return bcrypt.checkpw(plain_password.encode('utf-8'), hashed_password.encode('utf-8'))

# Create JWT token
def create_access_token(data: dict, expires_delta: timedelta = None):
    """Creates a JWT token with expiration time."""
    to_encode = data.copy()
    if expires_delta:
        expire = datetime.utcnow() + expires_delta
    else:
        expire = datetime.utcnow() + timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
    to_encode.update({"exp": expire})
    encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
    return encoded_jwt

# Verify JWT token
def verify_access_token(token: str):
    """Verifies the JWT token and returns the user_id if valid."""
    try:
        payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
        user_id: str = payload.get("user_id")
        if user_id is None:
            raise HTTPException(
                status_code=status.HTTP_401_UNAUTHORIZED,
                detail="Invalid token",
                headers={"WWW-Authenticate": "Bearer"},
            )
        return user_id
    except JWTError:
        raise HTTPException(
            status_code=status.HTTP_401_UNAUTHORIZED,
            detail="Invalid token",
            headers={"WWW-Authenticate": "Bearer"},
        )