import httpx

class BaseAPI():
    def __init__(self):
        self._client = httpx.AsyncClient()
        self.access_token = None # Placeholder, will be set by derived class or external config

    async def __aenter__(self):
        """Allows using the client with async with."""
        return self

    async def __aexit__(self, exc_type, exc_val, exc_tb):
        """Ensures the client is closed when exiting async with."""
        await self.close()

    async def close(self):
        """Closes the underlying asynchronous HTTP client."""
        if self._client: # Ensure _client exists before trying to close
            await self._client.close()

    async def _post(self, endpoint: str, data: dict = None):
        """
        Asynchronous helper method for making POST requests.
        This method will now implicitly use the _request method,
        so authentication logic is centralized.
        """
        return await self._request("POST", endpoint, json=data)

    async def _get(self, endpoint: str):
        """
        Asynchronous helper method for making GET requests.
        This method will now implicitly use the _request method,
        so authentication logic is centralized.
        """
        return await self._request("GET", endpoint)

    async def _request(self, method, endpoint, **kwargs):
        """
        Helper method to make an asynchronous HTTP request.
        This is where the access_token will be injected.

        Args:
            method (str): The HTTP method (e.g., 'GET', 'POST').
            endpoint (str): The API endpoint path (e.g., '/systems').
            **kwargs: Additional arguments for httpx.AsyncClient.request.

        Returns:
            dict: The JSON response from the API.

        Raises:
            httpx.HTTPStatusError: If the request returns a non-2xx status code.
            httpx.RequestError: For other request-related errors.
        """
        url = f"{self.base_url}{endpoint}" # base_url must be defined in derived class or passed to BaseAPI

        headers = kwargs.pop("headers", {})
        if self.access_token: # Check if access_token is set
            headers["Authorization"] = f"Bearer {self.access_token}"
        kwargs["headers"] = headers

        try:
            response = await self._client.request(method, url, **kwargs)
            response.raise_for_status() # Raise an exception for bad status codes (4xx or 5xx)
            return response.json()
        except httpx.HTTPStatusError as e:
            print(f"HTTP error occurred: {e}")
            raise
        except httpx.RequestError as e:
            print(f"An error occurred while requesting {e.request.url!r}: {e}")
            raise