/**
 * Copyright Microsoft Corporation. All rights reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import { showTraceViewer } from 'playwright-core/lib/server';
import type { Page } from 'playwright-core/lib/server/page';
import { ManualPromise } from 'playwright-core/lib/utils';
import type { FullResult } from '../../reporter';
import { clearCompilationCache, dependenciesForTestFile } from '../common/compilationCache';
import type { FullConfigInternal } from '../common/types';
import ListReporter from '../reporters/list';
import { Multiplexer } from '../reporters/multiplexer';
import { TeleReporterEmitter } from '../reporters/teleEmitter';
import { createReporter } from './reporters';
import type { TaskRunnerState } from './tasks';
import { createTaskRunnerForList, createTaskRunnerForWatch, createTaskRunnerForWatchSetup } from './tasks';
import { chokidar } from '../utilsBundle';
import type { FSWatcher } from 'chokidar';

class UIMode {
  private _config: FullConfigInternal;
  private _page!: Page;
  private _testRun: { run: Promise<FullResult['status']>, stop: ManualPromise<void> } | undefined;
  globalCleanup: (() => Promise<FullResult['status']>) | undefined;
  private _watcher: FSWatcher | undefined;
  private _watchTestFile: string | undefined;

  constructor(config: FullConfigInternal) {
    this._config = config;
    config._internal.passWithNoTests = true;
    for (const p of config.projects)
      p.retries = 0;
    config._internal.configCLIOverrides.use = config._internal.configCLIOverrides.use || {};
    config._internal.configCLIOverrides.use.trace = 'on';
  }

  async runGlobalSetup(): Promise<FullResult['status']> {
    const reporter = await createReporter(this._config, 'watch');
    const taskRunner = createTaskRunnerForWatchSetup(this._config, reporter);
    reporter.onConfigure(this._config);
    const context: TaskRunnerState = {
      config: this._config,
      reporter,
      phases: [],
    };
    const { status, cleanup: globalCleanup } = await taskRunner.runDeferCleanup(context, 0);
    if (status !== 'passed') {
      await globalCleanup();
      return status;
    }
    this.globalCleanup = globalCleanup;
    return status;
  }

  async showUI() {
    this._page = await showTraceViewer([], 'chromium', { watchMode: true });
    const exitPromise = new ManualPromise();
    this._page.on('close', () => exitPromise.resolve());
    this._page.exposeBinding('sendMessage', false, async (source, data) => {
      const { method, params }: { method: string, params: any } = data;
      if (method === 'list')
        await this._listTests();
      if (method === 'run')
        await this._runTests(params.testIds);
      if (method === 'stop')
        this._stopTests();
      if (method === 'watch')
        this._watchFile(params.fileName);
      if (method === 'exit')
        exitPromise.resolve();
    });
    await exitPromise;
  }

  private _dispatchEvent(message: any) {
    // eslint-disable-next-line no-console
    this._page.mainFrame().evaluateExpression(dispatchFuncSource, true, message).catch(e => console.log(e));
  }

  private async _listTests() {
    const listReporter = new TeleReporterEmitter(e => this._dispatchEvent(e));
    const reporter = new Multiplexer([listReporter]);
    const taskRunner = createTaskRunnerForList(this._config, reporter);
    const context: TaskRunnerState = { config: this._config, reporter, phases: [] };
    reporter.onConfigure(this._config);
    await taskRunner.run(context, 0);
  }

  private async _runTests(testIds: string[]) {
    await this._stopTests();

    const testIdSet = testIds ? new Set<string>(testIds) : null;
    this._config._internal.testIdMatcher = id => !testIdSet || testIdSet.has(id);

    const runReporter = new TeleReporterEmitter(e => this._dispatchEvent(e));
    const reporter = new Multiplexer([new ListReporter(), runReporter]);
    const taskRunner = createTaskRunnerForWatch(this._config, reporter);
    const context: TaskRunnerState = { config: this._config, reporter, phases: [] };
    clearCompilationCache();
    reporter.onConfigure(this._config);
    const stop = new ManualPromise();
    const run = taskRunner.run(context, 0, stop).then(async status => {
      await reporter.onExit({ status });
      this._testRun = undefined;
      this._config._internal.testIdMatcher = undefined;
      return status;
    });
    this._testRun = { run, stop };
    await run;
  }

  private async _watchFile(fileName: string) {
    if (this._watchTestFile === fileName)
      return;
    if (this._watcher)
      await this._watcher.close();
    this._watchTestFile = fileName;
    if (!fileName)
      return;

    const files = [fileName, ...dependenciesForTestFile(fileName)];
    this._watcher = chokidar.watch(files, { ignoreInitial: true }).on('all', async (event, file) => {
      if (event !== 'add' && event !== 'change')
        return;
      this._dispatchEvent({ method: 'fileChanged', params: { fileName: file } });
    });
  }

  private async _stopTests() {
    this._testRun?.stop?.resolve();
    await this._testRun?.run;
  }
}

const dispatchFuncSource = String((message: any) => {
  (window as any).dispatch(message);
});

export async function runUIMode(config: FullConfigInternal): Promise<FullResult['status']> {
  const uiMode = new UIMode(config);
  const status = await uiMode.runGlobalSetup();
  if (status !== 'passed')
    return status;
  await uiMode.showUI();
  return await uiMode.globalCleanup?.() || 'passed';
}