"""
Authentication client for Keynet platform

This module handles authentication operations with the Keynet server,
including login, token management, and validation.
"""

import base64
from typing import Optional

from .credentials import CredentialManager


class AuthClient:
    """Client for authentication operations with Keynet server"""

    def __init__(self, server_domain: str):
        self.server_domain = server_domain
        self.credential_manager = CredentialManager()

    def authenticate(self, username: str, password: str) -> tuple[bool, Optional[str]]:
        """
        Authenticate with the server and get a token

        Args:
            username: User's username
            password: User's password

        Returns:
            Tuple of (success, token or error message)

        """
        # TODO: Implement actual authentication with server
        # For now, mock authentication
        if username and password:
            # In real implementation, this would make an API call to:
            # POST https://{self.server_domain}/api/auth/login
            # with JSON body: {"username": username, "password": password}
            mock_token = base64.b64encode(
                f"{username}:{self.server_domain}".encode()
            ).decode()
            return True, mock_token
        return False, "Invalid credentials"

    def validate_token(self, token: str) -> bool:
        """
        Validate if a token is still valid

        Args:
            token: Authentication token to validate

        Returns:
            True if token is valid, False otherwise

        """
        # TODO: Implement actual token validation
        # For now, always return True for mock tokens
        return bool(token)

    def refresh_token(self, token: str) -> tuple[bool, Optional[str]]:
        """
        Refresh an authentication token

        Args:
            token: Current authentication token

        Returns:
            Tuple of (success, new token or error message)

        """
        # TODO: Implement token refresh
        # This would typically call:
        # POST https://{self.server_domain}/api/auth/refresh
        # with Authorization header
        if self.validate_token(token):
            # Return the same token for mock
            return True, token
        return False, "Invalid or expired token"

    def get_stored_token(self) -> Optional[str]:
        """
        Get stored authentication token for this server

        Returns:
            Token if available, None otherwise

        """
        creds = self.credential_manager.get_credentials(self.server_domain)
        if creds:
            username, password = creds
            success, token = self.authenticate(username, password)
            return token if success else None
        return None
