/**
 * Exports `server`, set up to start using setupTestSuite(), e.g.
 *
 *    import {assert, driver} from 'mocha-webdriver';
 *    import {server, setupTestSuite} from 'test/nbrowser/testUtils';
 *
 *    describe("MyTest", function() {
 *      this.timeout(20000);      // Needed because we wait for server for up to 15s.
 *      setupTestSuite();
 *    });
 *
 * Run with VERBOSE=1 in the environment to see the server log on the console. Normally it goes
 * into a file whose path is printed when server starts.
 *
 * Run `bin/mocha 'test/nbrowser/*.ts' -b --no-exit` to open a command-line prompt on
 * first-failure for debugging and quick reruns.
 */
import * as log from 'app/server/lib/log';
import {addToRepl, assert, driver, enableDebugCapture, Key, setOptionsModifyFunc, useServer} from 'mocha-webdriver';
import * as gu from 'test/nbrowser/gristUtils';
import {server} from 'test/nbrowser/testServer';

// Exports the server object with useful methods such as getHost(), waitServerReady(),
// simulateLogin(), etc.
export {server};

setOptionsModifyFunc(({chromeOpts, firefoxOpts}) => {
  // Set "kiosk" printing that saves to PDF without offering any dialogs. This applies to regular
  // (non-headless) Chrome. On headless Chrome, no dialog or output occurs regardless.
  chromeOpts.addArguments("--kiosk-printing");

  chromeOpts.setUserPreferences({
    // Don't show popups to save passwords, which are shown when running against a deployment when
    // we use a login form.
    "credentials_enable_service": false,
    "profile.password_manager_enabled" : false,

    // These preferences are my best effort to set up "print to pdf" that saves into the test's temp
    // dir, based on discussion here: https://bugs.chromium.org/p/chromedriver/issues/detail?id=2821.
    // On headless, it's ignored (no files are saved). When run manually, it would work EXCEPT with
    // kiosk-printing (i.e. also ignored), so look for your downloaded PDFs elsewhere (perhaps
    // ~/Downloads). Leaving it here in case it works better some day.
    "printing.default_destination_selection_rules": JSON.stringify({
      kind: "local",
      namePattern: "Save as PDF",
    }),
    "printing.print_preview_sticky_settings.appState": JSON.stringify({
      recentDestinations: [{
        id: 'Save as PDF',
        origin: 'local',
        account: '',
      }],
      version: 2
    }),
    "download.default_directory": server.testDir,
    "savefile.default_directory": server.testDir,
  });
});

interface TestSuiteOptions {
  samples?: boolean;
  team?: boolean;

  // If set, clear user preferences for all test users at the end of the suite. It should be used
  // for suites that modify preferences. Not that it only works in dev, not in deployment tests.
  clearUserPrefs?: boolean;
}

// Sets up the test suite to use the Grist server, and also to record logs and screenshots after
// failed tests (if MOCHA_WEBDRIVER_LOGDIR var is set).
//
// Returns a Cleanup instance as a convenience, for use scheduling any clean-up that would have
// the same scope as the test suite.
export function setupTestSuite(options?: TestSuiteOptions) {
  useServer(server);
  enableDebugCapture();
  addToRepl('gu', gu, 'gristUtils, grist-specific helpers');
  addToRepl('Key', Key, 'key values such as Key.ENTER');
  addToRepl('server', server, 'test server');

  // After every suite, assert it didn't leave new browser windows open.
  checkForExtraWindows();

  // After every suite, clear sessionStorage and localStorage to avoid affecting other tests.
  after(clearCurrentWindowStorage);

  // If requested, clear user preferences for all test users after this suite.
  if (options?.clearUserPrefs) {
    after(clearTestUserPreferences);
  }

  // Though unlikely it is possible that the server was left paused by a previous test, so let's
  // always call resume.
  afterEach(() => server.resume());

  return setupRequirement({team: true, ...options});
}

// Clean up any browser windows after the test suite that didn't exist at its start.
function checkForExtraWindows() {
  let origHandles: string[];
  before(async () => {
    origHandles = await driver.getAllWindowHandles();
  });
  after(async () => {
    assert.deepEqual(await driver.getAllWindowHandles(), origHandles);
  });
}

// Clean up any browser windows after the test suite that didn't exist at its start.
// Call this BEFORE setupTestSuite() when the test is expected to create new windows, so that they
// may get cleaned up before the check for extraneous windows runs.
export function cleanupExtraWindows() {
  let origHandles: string[];
  before(async () => {
    origHandles = await driver.getAllWindowHandles();
  });
  after(async () => {
    const newHandles = await driver.getAllWindowHandles();
    for (const w of newHandles) {
      if (!origHandles.includes(w)) {
        await driver.switchTo().window(w);
        await driver.close();
      }
    }
    await driver.switchTo().window(newHandles[0]);
  });
}


async function clearCurrentWindowStorage() {
  if ((await driver.getCurrentUrl()).startsWith('http')) {
    try {
      await driver.executeScript('window.sessionStorage.clear(); window.localStorage.clear();');
    } catch (err) {
      log.info("Could not clear window storage after the test ended: %s", err.message);
    }
  }
}

async function clearTestUserPreferences() {
  // After every suite, clear user preferences for all test users.
  const dbManager = await server.getDatabase();
  let emails = Object.keys(gu.TestUserEnum).map(user => gu.translateUser(user as any).email);
  emails = [...new Set(emails)];    // Remove duplicates.
  await dbManager.testClearUserPrefs(emails);
}

export type CleanupFunc = (() => void|Promise<void>);

/**
 * Helper to run cleanup callbacks created in a test case. See setupCleanup() below for usage.
 */
export class Cleanup {
  private _callbacksAfterAll: CleanupFunc[] = [];
  private _callbacksAfterEach: CleanupFunc[] = [];

  public addAfterAll(cleanupFunc: CleanupFunc) {
    this._callbacksAfterAll.push(cleanupFunc);
  }
  public addAfterEach(cleanupFunc: CleanupFunc) {
    this._callbacksAfterEach.push(cleanupFunc);
  }

  public async runCleanup(which: 'all'|'each') {
    const callbacks = which === 'all' ? this._callbacksAfterAll : this._callbacksAfterEach;
    const list = callbacks.splice(0);   // Get a copy of the list AND clear it out.
    for (const f of list) {
      await f();
    }
  }
}

/**
 * Helper to run cleanup callbacks created in the course of running a test.
 * Usage:
 *    const cleanup = setupCleanup();
 *    it("should do stuff", function() {
 *      cleanup.addAfterAll(() => { ...doSomething1()... });
 *      cleanup.addAfterEach(() => { ...doSomething2()... });
 *    });
 *
 * Here, doSomething1() is called at the end of a suite, while doSomething2() is called at the end
 * of the current test case.
 */
export function setupCleanup() {
  const cleanup = new Cleanup();
  after(() => cleanup.runCleanup('all'));
  afterEach(() => cleanup.runCleanup('each'));
  return cleanup;
}

/**
 * Implement some optional requirements for a test, such as having an example document
 * present, or a team site to run tests in.  These requirements should be automatically
 * satisfied by staging/prod deployments, and only need doing in self-contained tests
 * or tests against dev servers.
 *
 * Returns a Cleanup instance for any cleanup that would have the same scope as the
 * requirement.
 */
export function setupRequirement(options: TestSuiteOptions) {
  const cleanup = setupCleanup();
  if (options.samples) {
    if (!server.isExternalServer()) {
      gu.shareSupportWorkspaceForSuite(); // TODO: Remove after the support workspace is removed from the backend.
      gu.addSamplesForSuite();
    }
  }

  before(async function() {

    if (new URL(server.getHost()).hostname !== 'localhost') {
      // Non-dev servers should already meet the requirements; in any case we should not
      // fiddle with them here.
      return;
    }

    // Optionally ensure that a team site is available for tests.
    if (options.team) {
      const api = gu.createHomeApi('support', 'docs');
      let orgName = 'test-grist';
      const deployment = process.env.GRIST_ID_PREFIX;
      if (deployment) { orgName = `${orgName}-${deployment}`; }
      let isNew: boolean = false;
      try {
        await api.newOrg({name: 'Test Grist', domain: orgName});
        isNew = true;
      } catch (e) {
        // Assume the org already exists.
      }
      if (isNew) {
        await api.updateOrgPermissions(orgName, {
          users: {
            'gristoid+chimpy@gmail.com': 'owners',
          }
        });
        // Recreate the api for the correct org, then update billing.
        const api2 = gu.createHomeApi('support', orgName);
        const billing = api2.getBillingAPI();
        await billing.updateBillingManagers({
          users: {
            'gristoid+chimpy@gmail.com': 'managers',
          }
        });
      }
    }
  });
  return cleanup;
}
