from datetime import datetime, timedelta, timezone

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

from app.config import get_settings


# Use PBKDF2 for new hashes to avoid bcrypt backend/version issues and
# bcrypt's 72-byte password input limit. Keep bcrypt for legacy verification.
pwd_context = CryptContext(
    schemes=["pbkdf2_sha256", "bcrypt"],
    deprecated="auto",
)
settings = get_settings()


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


def verify_password(password: str, password_hash: str) -> bool:
    return pwd_context.verify(password, password_hash)


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


def decode_access_token(token: str) -> str | None:
    try:
        payload = jwt.decode(token, settings.secret_key, algorithms=[settings.algorithm])
        subject = payload.get("sub")
        return str(subject) if subject is not None else None
    except JWTError:
        return None