// Copyright (c) 2016 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

import * as Common from '../../core/common/common.js';
import * as i18n from '../../core/i18n/i18n.js';
import * as Platform from '../../core/platform/platform.js';
import * as SDK from '../../core/sdk/sdk.js';
import * as UI from '../../ui/legacy/legacy.js';

import {DeveloperResourcesListView} from './DeveloperResourcesListView.js';
import developerResourcesViewStyles from './developerResourcesView.css.js';

const UIStrings = {
  /**
  *@description Placeholder for a search field in a toolbar
  */
  enterTextToSearchTheUrlAndError: 'Enter text to search the URL and Error columns',
  /**
  * @description Tooltip for a checkbox in the toolbar of the developer resources view. The
  * inspected target is the webpage that DevTools is debugging/inspecting/attached to.
  */
  loadHttpsDeveloperResources: 'Load `HTTP(S)` developer resources through the inspected target',
  /**
  * @description Text for a checkbox in the toolbar of the developer resources view. The target is
  * the webpage that DevTools is debugging/inspecting/attached to. This setting makes it so
  * developer resources are requested from the webpage itself, and not from the DevTools
  * application.
  */
  enableLoadingThroughTarget: 'Enable loading through target',
  /**
   *@description Text for resources load status
   *@example {1} PH1
   *@example {1} PH2
   */
  resourcesCurrentlyLoading: '{PH1} resources, {PH2} currently loading',
  /**
   * @description Status text that appears to tell the developer how many resources were loaded in
   * total. Resources are files related to the webpage.
   */
  resources: '{n, plural, =1 {# resource} other {# resources}}',
};
const str_ = i18n.i18n.registerUIStrings('panels/developer_resources/DeveloperResourcesView.ts', UIStrings);
const i18nString = i18n.i18n.getLocalizedString.bind(undefined, str_);

let developerResourcesViewInstance: DeveloperResourcesView;

export class DeveloperResourcesView extends UI.Widget.VBox {
  private textFilterRegExp: RegExp|null;
  private readonly filterInput: UI.Toolbar.ToolbarInput;
  private readonly coverageResultsElement: HTMLElement;
  private listView: DeveloperResourcesListView;
  private readonly statusToolbarElement: HTMLElement;
  private statusMessageElement: HTMLElement;
  private readonly throttler: Common.Throttler.Throttler;
  private readonly loader: SDK.PageResourceLoader.PageResourceLoader;
  private constructor() {
    super(true);

    const toolbarContainer = this.contentElement.createChild('div', 'developer-resource-view-toolbar-container');
    const toolbar = new UI.Toolbar.Toolbar('developer-resource-view-toolbar', toolbarContainer);

    this.textFilterRegExp = null;
    const accessiblePlaceholder = '';  // Indicates that ToobarInput should use the placeholder as ARIA label.
    this.filterInput =
        new UI.Toolbar.ToolbarInput(i18nString(UIStrings.enterTextToSearchTheUrlAndError), accessiblePlaceholder, 1);
    this.filterInput.addEventListener(UI.Toolbar.ToolbarInput.Event.TextChanged, this.onFilterChanged, this);
    toolbar.appendToolbarItem(this.filterInput);

    const loadThroughTarget = SDK.PageResourceLoader.getLoadThroughTargetSetting();
    const loadThroughTargetCheckbox = new UI.Toolbar.ToolbarSettingCheckbox(
        loadThroughTarget, i18nString(UIStrings.loadHttpsDeveloperResources),
        i18nString(UIStrings.enableLoadingThroughTarget));
    toolbar.appendToolbarItem(loadThroughTargetCheckbox);

    this.coverageResultsElement = this.contentElement.createChild('div', 'developer-resource-view-results');
    this.listView = new DeveloperResourcesListView(this.isVisible.bind(this));
    this.listView.show(this.coverageResultsElement);
    this.statusToolbarElement = this.contentElement.createChild('div', 'developer-resource-view-toolbar-summary');
    this.statusMessageElement = this.statusToolbarElement.createChild('div', 'developer-resource-view-message');

    this.throttler = new Common.Throttler.Throttler(100);
    this.loader = SDK.PageResourceLoader.PageResourceLoader.instance();
    this.loader.addEventListener(SDK.PageResourceLoader.Events.Update, this.onUpdate, this);
    this.onUpdate();
  }

  static instance(): DeveloperResourcesView {
    if (!developerResourcesViewInstance) {
      developerResourcesViewInstance = new DeveloperResourcesView();
    }
    return developerResourcesViewInstance;
  }

  private onUpdate(): void {
    void this.throttler.schedule(this.update.bind(this));
  }

  private async update(): Promise<void> {
    this.listView.reset();
    this.listView.update(this.loader.getResourcesLoaded().values());
    this.updateStats();
  }

  private updateStats(): void {
    const {loading, resources} = this.loader.getNumberOfResources();
    if (loading > 0) {
      this.statusMessageElement.textContent =
          i18nString(UIStrings.resourcesCurrentlyLoading, {PH1: resources, PH2: loading});
    } else {
      this.statusMessageElement.textContent = i18nString(UIStrings.resources, {n: resources});
    }
  }

  private isVisible(item: SDK.PageResourceLoader.PageResource): boolean {
    return !this.textFilterRegExp || this.textFilterRegExp.test(item.url) ||
        this.textFilterRegExp.test(item.errorMessage || '');
  }

  /**
   *
   */
  private onFilterChanged(): void {
    if (!this.listView) {
      return;
    }

    const text = this.filterInput.value();
    this.textFilterRegExp = text ? Platform.StringUtilities.createPlainTextSearchRegex(text, 'i') : null;
    this.listView.updateFilterAndHighlight(this.textFilterRegExp);
    this.updateStats();
  }
  wasShown(): void {
    super.wasShown();
    this.registerCSSFiles([developerResourcesViewStyles]);
  }
}