from rest_framework import exceptions, status
from rest_framework.response import Response
from rest_framework.views import exception_handler, set_rollback
from rest_framework.exceptions import (
    ErrorDetail,
    AuthenticationFailed,
    APIException,
    PermissionDenied,
    NotFound
)


class ExceptionHandler:
    def get_domain(self):
        """
        Domain examples
        """
        if self.status_code >= 500:
            return 'data_process'
        return 'request'

    def get_full_details(self, detail):
        if isinstance(detail, list):
            return [self.get_full_details(item) for item in detail]
        elif isinstance(detail, dict):
            return {
                'domain': self.get_domain(),
                'state': {
                    key: self.get_full_details(value)
                    for key, value in detail.items()
                }
            }
        return {
            'message': str(detail),
            'reason': detail.code
        }

    def get_exception_message(self):
        status_code = self.status_code
        exception_string = _('Bad request')

        # TODO: refactor to a map with more options of exception messages
        if status_code >= status.HTTP_500_INTERNAL_SERVER_ERROR:
            exception_string = APIException.default_detail
        elif status_code == status.HTTP_401_UNAUTHORIZED:
            exception_string = AuthenticationFailed.default_detail
        elif status_code == status.HTTP_403_FORBIDDEN:
            exception_string = PermissionDenied.default_detail
        elif status_code == status.HTTP_404_NOT_FOUND:
            exception_string = NotFound.default_detail

        return exception_string

    def __call__(self, exc, context):
        # Call REST framework's default exception handler first,
        # to get the standard error response.
        response = exception_handler(exc, context)

        self.status_code = response.status_code

        if response is not None and hasattr(exc, 'detail'):
            response.data = {
                'code': self.status_code,
                'message': self.get_exception_message()
            }

            full_details = self.get_full_details(exc.detail)

            if isinstance(full_details, dict):
                errors = [{
                    'message': exc.default_detail,
                    'domain': self.get_domain(),
                    'reason': exc.default_code,
                    **full_details
                }]
            else:
                errors = full_details

            response.data['errors'] = errors

        return response


custom_exception_handler3 = ExceptionHandler()