"""
MFE API Views for useful information related to mfes.
"""

import edx_api_doc_tools as apidocs
from django.conf import settings
from django.http import HttpResponseNotFound, JsonResponse
from django.utils.decorators import method_decorator
from django.views.decorators.cache import cache_page
from rest_framework import status
from rest_framework.views import APIView

from openedx.core.djangoapps.site_configuration import helpers as configuration_helpers


class MFEConfigView(APIView):
    """
    Provides an API endpoint to get the MFE configuration from settings (or site configuration).
    """

    @method_decorator(cache_page(settings.MFE_CONFIG_API_CACHE_TIMEOUT))
    @apidocs.schema(
        parameters=[
            apidocs.query_parameter(
                'mfe',
                str,
                description="Name of an MFE (a.k.a. an APP_ID).",
            ),
        ],
    )
    def get(self, request):
        """
        Return the MFE configuration, optionally including MFE-specific overrides.

        **Usage**

          Get common config:
          GET /api/mfe_config/v1

          Get app config (common + app-specific overrides):
          GET /api/mfe_config/v1?mfe=name_of_mfe

        **GET Response Values**
        ```
        {
            "BASE_URL": "https://name_of_mfe.example.com",
            "LANGUAGE_PREFERENCE_COOKIE_NAME": "example-language-preference",
            "CREDENTIALS_BASE_URL": "https://credentials.example.com",
            "DISCOVERY_API_BASE_URL": "https://discovery.example.com",
            "LMS_BASE_URL": "https://courses.example.com",
            "LOGIN_URL": "https://courses.example.com/login",
            "LOGOUT_URL": "https://courses.example.com/logout",
            "STUDIO_BASE_URL": "https://studio.example.com",
            "LOGO_URL": "https://courses.example.com/logo.png",
            ... and so on
        }
        ```
        """

        if not settings.ENABLE_MFE_CONFIG_API:
            return HttpResponseNotFound()

        mfe_config = configuration_helpers.get_value('MFE_CONFIG', settings.MFE_CONFIG)
        if request.query_params.get('mfe'):
            mfe = str(request.query_params.get('mfe'))
            app_config = configuration_helpers.get_value(
                'MFE_CONFIG_OVERRIDES',
                settings.MFE_CONFIG_OVERRIDES,
            )
            mfe_config.update(app_config.get(mfe, {}))
        return JsonResponse(mfe_config, status=status.HTTP_200_OK)