from datetime import datetime, timedelta, timezone

import bcrypt
from jose import JWTError, jwt

from .config import get_settings

settings = get_settings()

# bcrypt akzeptiert maximal 72 Bytes – längere Passwörter werden abgeschnitten.
_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(password: str, password_hash: str) -> bool:
    try:
        pw = password.encode("utf-8")[:_BCRYPT_MAX_BYTES]
        return bcrypt.checkpw(pw, password_hash.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.jwt_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