import { beforeEach, describe, expect, it, jest, test } from "@jest/globals";
import { ApiBasedRepositoryLoader } from "../../src/loaders/ApiBasedRepositoryLoader";
import { UnoptimizedInMemoryRepository } from "../../src/repositories/UnoptimizedInMemoryRepository";
import { getAllSystemsResponse } from "../jsonSnapshots/getAllSystemsResponse";

function updateGlobalFetchMockJson(obj: any) {
  // @ts-ignore
  global.fetch = jest.fn(() => {
    return Promise.resolve({
      json: () => Promise.resolve(obj)
    })
  }) as jest.Mock;
}

/**
 * Reset the global fetch function mock's JSON to return an empty object.
 * @param obj
 */
function resetGlobalFetchMockJson() {
  updateGlobalFetchMockJson({})
}

describe("ApiBasedRepositoryLoader", () => {
  let loader: ApiBasedRepositoryLoader;

  beforeEach(() => {
    loader = new ApiBasedRepositoryLoader(new UnoptimizedInMemoryRepository());
    resetGlobalFetchMockJson();
  });

  describe("fetchAndUpdateSystemData", () => {
    it("updates system data in repository if response received", async () => {
      const numberOfSystemsInResponse = getAllSystemsResponse.all.length;
      updateGlobalFetchMockJson(getAllSystemsResponse);

      await loader.fetchAndUpdateSystemData();

      const systems = await loader.repository.getSystems();
      if (loader.supportedSystemIds.length < numberOfSystemsInResponse) {
        expect(systems).toHaveLength(loader.supportedSystemIds.length);
      } else {
        expect(systems).toHaveLength(numberOfSystemsInResponse);
      }
    });

    it("throws the correct error if the API response contains no data", async () => {

    });
  });

  describe("fetchAndUpdateRouteDataForExistingSystems", () => {
    it("updates route data in repository if there are systems and response received", async () => {

    });

    it("throws the correct error if the API response contains no data", async () => {

    });
  });

  describe("fetchAndUpdateStopAndPolylineDataForRoutesInExistingSystems", () => {
    it("updates stop and polyline data if there are systems and response received", async () => {

    });

    it("throws the correct error if the API response contains no data", async () => {

    })
  });

  describe("fetchAndUpdateShuttleDataForExistingSystems", () => {
    it("updates shuttle data in repository if there are systems and response received", async () => {

    });

    it("throws the correct error if the API response contains no data", async () => {

    });
  });

  describe("fetchAndUpdateEtaDataForExistingSystems", () => {
    it("updates shuttle data in repository if there are systems and response received", async () => {

    });

    it("throws the correct error if the API response contains no data", async () => {

    });
  });
});