admin / Bid-Sentinel

"""Password hashing and JWT helpers."""
from datetime import datetime, timedelta, timezone

import bcrypt
from jose import JWTError, jwt

from app.config import settings

# bcrypt has a hard 72-byte limit on the password input; longer inputs are
# truncated by the algorithm, so we truncate explicitly for predictable behaviour.
_BCRYPT_MAX_BYTES = 72


def hash_password(password: str) -> str:
    pw = password.encode("utf-8")[:_BCRYPT_MAX_BYTES]
    return bcrypt.hashpw(pw, bcrypt.gensalt()).decode("utf-8")


def verify_password(plain: str, hashed: str) -> bool:
    try:
        return bcrypt.checkpw(
            plain.encode("utf-8")[:_BCRYPT_MAX_BYTES], hashed.encode("utf-8")
        )
    except (ValueError, TypeError):
        return False


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


def decode_access_token(token: str) -> dict | None:
    try:
        return jwt.decode(token, settings.jwt_secret, algorithms=[settings.jwt_algorithm])
    except JWTError:
        return None