from datetime import datetime, timedelta, timezone
from typing import Optional

from jose import JWTError, jwt
from passlib.context import CryptContext

from app.core.config import settings

pwd_context = CryptContext(schemes=["pbkdf2_sha256"], deprecated="auto")
ALGORITHM = "HS256"


def verify_password(plain_password: str, hashed_password: str) -> bool:
    return pwd_context.verify(plain_password, hashed_password)


def get_password_hash(password: str) -> str:
    return pwd_context.hash(password)


def create_access_token(subject: str) -> str:
    expire = datetime.now(timezone.utc) + timedelta(minutes=settings.access_token_expire_minutes)
    payload = {"sub": subject, "exp": expire}
    return jwt.encode(payload, settings.secret_key, algorithm=ALGORITHM)


def decode_access_token(token: str) -> Optional[str]:
    try:
        payload = jwt.decode(token, settings.secret_key, algorithms=[ALGORITHM])
    except JWTError:
        return None

    subject = payload.get("sub")
    if not isinstance(subject, str) or not subject:
        return None

    return subject