"""
Shared JWT Authentication Handler
Used across all microservices for consistent authentication
"""

from jose import jwt
from datetime import datetime, timedelta, timezone
from typing import Optional, Dict, Any
import logging

logger = logging.getLogger(__name__)

class JWTHandler:
    """JWT token handling for microservices"""
    
    def __init__(self, secret_key: str, algorithm: str = "HS256"):
        self.secret_key = secret_key
        self.algorithm = algorithm
    
    def create_access_token(self, data: Dict[str, Any], expires_delta: Optional[timedelta] = None) -> str:
        """Create JWT access token"""
        to_encode = data.copy()
        
        if expires_delta:
            expire =  datetime.now(timezone.utc) + expires_delta
        else:
            expire =  datetime.now(timezone.utc) + timedelta(minutes=30)
        
        to_encode.update({"exp": expire, "type": "access"})
        
        encoded_jwt = jwt.encode(to_encode, self.secret_key, algorithm=self.algorithm)
        return encoded_jwt
    
    def create_refresh_token(self, data: Dict[str, Any], expires_delta: Optional[timedelta] = None) -> str:
        """Create JWT refresh token"""
        to_encode = data.copy()
        
        if expires_delta:
            expire =  datetime.now(timezone.utc) + expires_delta
        else:
            expire =  datetime.now(timezone.utc) + timedelta(days=7)
        
        to_encode.update({"exp": expire, "type": "refresh"})
        
        encoded_jwt = jwt.encode(to_encode, self.secret_key, algorithm=self.algorithm)
        return encoded_jwt
    
    def verify_token(self, token: str) -> Optional[Dict[str, Any]]:
        """Verify and decode JWT token"""
        try:
            payload = jwt.decode(token, self.secret_key, algorithms=[self.algorithm])
            return payload
        except jwt.ExpiredSignatureError:
            logger.warning("Token has expired")
            return None
        except jwt.JWTError:
            logger.warning("Invalid token")
            return None