# -*- coding: utf-8 -*-

import json

from django import http


COORS_ALLOWED_ORIGINS = '*'
COORS_ALLOWED_METHODS = ['POST', 'GET', 'OPTIONS', 'PUT', 'DELETE', 'PATCH', 'HEAD']
COORS_ALLOWED_HEADERS = ['content-type', 'x-requested-with',
                         'authorization', 'accept-encoding',
                         'x-disable-pagination', 'x-host']
COORS_ALLOWED_CREDENTIALS = True
COORS_EXPOSE_HEADERS = ["x-pagination-count", "x-paginated", "x-paginated-by",
                        "x-paginated-by", "x-pagination-current", "x-site-host",
                        "x-site-register"]


class CoorsMiddleware(object):
    def _populate_response(self, response):
        response["Access-Control-Allow-Origin"]  = COORS_ALLOWED_ORIGINS
        response["Access-Control-Allow-Methods"] = ",".join(COORS_ALLOWED_METHODS)
        response["Access-Control-Allow-Headers"] = ",".join(COORS_ALLOWED_HEADERS)
        response["Access-Control-Expose-Headers"] = ",".join(COORS_EXPOSE_HEADERS)

        if COORS_ALLOWED_CREDENTIALS:
            response["Access-Control-Allow-Credentials"] = 'true'

    def process_request(self, request):
        if 'HTTP_ACCESS_CONTROL_REQUEST_METHOD' in request.META:
            response = http.HttpResponse()
            self._populate_response(response)
            return response
        return None

    def process_response(self, request, response):
        self._populate_response(response)
        return response