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

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

async def verify_password(plain_password: str, hashed_password: str) -> bool:
    # Truncate password if too long for bcrypt (72 bytes limit)
    if len(plain_password.encode('utf-8')) > 72:
        plain_password = plain_password[:72]
    return await anyio.to_thread.run_sync(pwd_context.verify, plain_password, hashed_password)

async def get_password_hash(password: str) -> str:
    # Truncate password if too long for bcrypt (72 bytes limit)
    if len(password.encode('utf-8')) > 72:
        password = password[:72]
    return await anyio.to_thread.run_sync(pwd_context.hash, password)

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