from datetime import datetime, timedelta
from typing import Any, Union
from jose import jwt
from passlib.context import CryptContext
from app.core.config import settings

pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")

def create_access_token(
    subject: Union[str, Any], expires_delta: timedelta = None
) -> str:
    if expires_delta:
        expire = datetime.utcnow() + expires_delta
    else:
        expire = datetime.utcnow() + timedelta(
            minutes=settings.ACCESS_TOKEN_EXPIRE_MINUTES
        )
    to_encode = {"exp": expire, "sub": str(subject)}
    encoded_jwt = jwt.encode(
        to_encode, settings.SECRET_KEY, algorithm="HS256"
    )
    return encoded_jwt

def verify_password(plain_password: str, hashed_password: str) -> bool:
    # Truncate password to 72 bytes to avoid bcrypt limitation
    # Handle byte truncation correctly
    pwd_bytes = plain_password.encode('utf-8')
    if len(pwd_bytes) > 72:
        pwd_bytes = pwd_bytes[:72]
    # Passlib can handle bytes for bcrypt
    return pwd_context.verify(pwd_bytes, hashed_password)

def get_password_hash(password: str) -> str:
    # Truncate password to 72 bytes to avoid bcrypt limitation
    pwd_bytes = password.encode('utf-8')
    if len(pwd_bytes) > 72:
        pwd_bytes = pwd_bytes[:72]
    
    # print(f"DEBUG: Hashing password of length {len(pwd_bytes)}")
    return pwd_context.hash(pwd_bytes)
