// Copyright 2021 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.

/*
 * Copyright (C) 2007, 2008 Apple Inc.  All rights reserved.
 * Copyright (C) 2008, 2009 Anthony Ricaud <rik@webkit.org>
 * Copyright (C) 2011 Google Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1.  Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 * 2.  Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
 *     its contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

import * as Common from '../../core/common/common.js';
import * as Host from '../../core/host/host.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 Bindings from '../../models/bindings/bindings.js';
import * as Logs from '../../models/logs/logs.js';
import * as Workspace from '../../models/workspace/workspace.js';
import * as NetworkForward from '../../panels/network/forward/forward.js';
import * as IconButton from '../../ui/components/icon_button/icon_button.js';
import * as PerfUI from '../../ui/legacy/components/perf_ui/perf_ui.js';
import * as UI from '../../ui/legacy/legacy.js';
import * as MobileThrottling from '../mobile_throttling/mobile_throttling.js';
import * as Search from '../search/search.js';

import {BlockedURLsPane} from './BlockedURLsPane.js';
import type {RequestActivatedEvent} from './NetworkDataGridNode.js';
import {Events} from './NetworkDataGridNode.js';
import {NetworkItemView} from './NetworkItemView.js';
import {NetworkLogView} from './NetworkLogView.js';
import {NetworkOverview} from './NetworkOverview.js';
import networkPanelStyles from './networkPanel.css.js';
import {NetworkSearchScope} from './NetworkSearchScope.js';

import type {NetworkTimeCalculator} from './NetworkTimeCalculator.js';
import {NetworkTransferTimeCalculator} from './NetworkTimeCalculator.js';

const UIStrings = {
  /**
  *@description Text to close something
  */
  close: 'Close',
  /**
  *@description Title of a search bar or tool
  */
  search: 'Search',
  /**
  *@description Text to clear content
  */
  clear: 'Clear',
  /**
  *@description Tooltip text that appears on the setting to preserve log when hovering over the item
  */
  doNotClearLogOnPageReload: 'Do not clear log on page reload / navigation',
  /**
  *@description Text to preserve the log after refreshing
  */
  preserveLog: 'Preserve log',
  /**
  *@description Text to disable cache while DevTools is open
  */
  disableCacheWhileDevtoolsIsOpen: 'Disable cache (while DevTools is open)',
  /**
  *@description Text in Network Config View of the Network panel
  */
  disableCache: 'Disable cache',
  /**
  *@description Tooltip text that appears when hovering over the largeicon settings gear in show settings pane setting in network panel of the network panel
  */
  networkSettings: 'Network settings',
  /**
  *@description Tooltip for expanding network request row setting
  */
  showMoreInformationInRequestRows: 'Show more information in request rows',
  /**
  *@description Text in Network Panel of the Network panel
  */
  useLargeRequestRows: 'Use large request rows',
  /**
  *@description Tooltip text for network request overview setting
  */
  showOverviewOfNetworkRequests: 'Show overview of network requests',
  /**
  *@description Text in Network Panel of the Network panel
  */
  showOverview: 'Show overview',
  /**
  *@description Tooltip for group by frame network setting
  */
  groupRequestsByTopLevelRequest: 'Group requests by top level request frame',
  /**
  *@description Text in Network Panel of the Network panel
  */
  groupByFrame: 'Group by frame',
  /**
  *@description Tooltip for capture screenshot network setting
  */
  captureScreenshotsWhenLoadingA: 'Capture screenshots when loading a page',
  /**
  *@description Text to take screenshots
  */
  captureScreenshots: 'Capture screenshots',
  /**
  * @description Tooltip text that appears when hovering over the largeicon load button in the
  * Network Panel. This action prompts the user to select a HAR file to upload to DevTools.
  */
  importHarFile: 'Import `HAR` file...',
  /**
  * @description Tooltip text that appears when hovering over the largeicon download button in the
  * Network Panel. HAR is a file format (HTTP Archive) and should not be translated. This action
  * triggers the download of a HAR file.
  */
  exportHar: 'Export `HAR`...',
  /**
  *@description Text for throttling the network
  */
  throttling: 'Throttling',
  /**
  *@description Text in Network Panel of the Network panel
  *@example {Ctrl + R} PH1
  */
  hitSToReloadAndCaptureFilmstrip: 'Hit {PH1} to reload and capture filmstrip.',
  /**
  *@description A context menu item in the Network Panel of the Network panel
  */
  revealInNetworkPanel: 'Reveal in Network panel',
  /**
  *@description Text in Network Panel of the Network panel
  */
  recordingFrames: 'Recording frames...',
  /**
  *@description Text in Network Panel of the Network panel
  */
  fetchingFrames: 'Fetching frames...',
  /**
   * @description Text of a button in the Network panel's toolbar that open Network Conditions panel in the drawer.
   */
  moreNetworkConditions: 'More network conditions…',
};
const str_ = i18n.i18n.registerUIStrings('panels/network/NetworkPanel.ts', UIStrings);
const i18nString = i18n.i18n.getLocalizedString.bind(undefined, str_);
let networkPanelInstance: NetworkPanel;

export class NetworkPanel extends UI.Panel.Panel implements UI.ContextMenu.Provider, UI.View.ViewLocationResolver {
  private readonly networkLogShowOverviewSetting: Common.Settings.Setting<boolean>;
  private readonly networkLogLargeRowsSetting: Common.Settings.Setting<boolean>;
  private readonly networkRecordFilmStripSetting: Common.Settings.Setting<boolean>;
  private readonly toggleRecordAction: UI.ActionRegistration.Action;
  private pendingStopTimer!: number|undefined;
  networkItemView: NetworkItemView|null;
  private filmStripView: PerfUI.FilmStripView.FilmStripView|null;
  private filmStripRecorder: FilmStripRecorder|null;
  private currentRequest: SDK.NetworkRequest.NetworkRequest|null;
  private readonly panelToolbar: UI.Toolbar.Toolbar;
  private readonly rightToolbar: UI.Toolbar.Toolbar;
  private readonly filterBar: UI.FilterBar.FilterBar;
  private readonly settingsPane: UI.Widget.HBox;
  private showSettingsPaneSetting: Common.Settings.Setting<boolean>;
  private readonly filmStripPlaceholderElement: HTMLElement;
  private readonly overviewPane: PerfUI.TimelineOverviewPane.TimelineOverviewPane;
  private readonly networkOverview: NetworkOverview;
  private readonly overviewPlaceholderElement: HTMLElement;
  private readonly calculator: NetworkTransferTimeCalculator;
  private splitWidget: UI.SplitWidget.SplitWidget;
  private readonly sidebarLocation: UI.View.TabbedViewLocation;
  private readonly progressBarContainer: HTMLDivElement;
  networkLogView: NetworkLogView;
  private readonly fileSelectorElement: HTMLElement;
  private readonly detailsWidget: UI.Widget.VBox;
  private readonly closeButtonElement: HTMLDivElement;
  private preserveLogSetting: Common.Settings.Setting<boolean>;
  recordLogSetting: Common.Settings.Setting<boolean>;
  private readonly throttlingSelect: UI.Toolbar.ToolbarComboBox;

  constructor() {
    super('network');

    this.networkLogShowOverviewSetting =
        Common.Settings.Settings.instance().createSetting('networkLogShowOverview', true);
    this.networkLogLargeRowsSetting = Common.Settings.Settings.instance().createSetting('networkLogLargeRows', false);
    this.networkRecordFilmStripSetting =
        Common.Settings.Settings.instance().createSetting('networkRecordFilmStripSetting', false);
    this.toggleRecordAction =
        (UI.ActionRegistry.ActionRegistry.instance().action('network.toggle-recording') as
         UI.ActionRegistration.Action);
    this.networkItemView = null;
    this.filmStripView = null;
    this.filmStripRecorder = null;
    this.currentRequest = null;

    const panel = new UI.Widget.VBox();

    const networkToolbarContainer = panel.contentElement.createChild('div', 'network-toolbar-container');
    this.panelToolbar = new UI.Toolbar.Toolbar('', networkToolbarContainer);
    this.panelToolbar.makeWrappable(true);
    this.rightToolbar = new UI.Toolbar.Toolbar('', networkToolbarContainer);

    this.filterBar = new UI.FilterBar.FilterBar('networkPanel', true);
    this.filterBar.show(panel.contentElement);
    this.filterBar.addEventListener(UI.FilterBar.FilterBarEvents.Changed, this.handleFilterChanged.bind(this));

    this.settingsPane = new UI.Widget.HBox();
    this.settingsPane.element.classList.add('network-settings-pane');
    this.settingsPane.show(panel.contentElement);
    this.showSettingsPaneSetting =
        Common.Settings.Settings.instance().createSetting('networkShowSettingsToolbar', false);
    this.showSettingsPaneSetting.addChangeListener(this.updateSettingsPaneVisibility.bind(this));
    this.updateSettingsPaneVisibility();

    this.filmStripPlaceholderElement = panel.contentElement.createChild('div', 'network-film-strip-placeholder');

    // Create top overview component.
    this.overviewPane = new PerfUI.TimelineOverviewPane.TimelineOverviewPane('network');
    this.overviewPane.addEventListener(
        PerfUI.TimelineOverviewPane.Events.WindowChanged, this.onWindowChanged.bind(this));
    this.overviewPane.element.id = 'network-overview-panel';
    this.networkOverview = new NetworkOverview();
    this.overviewPane.setOverviewControls([this.networkOverview]);
    this.overviewPlaceholderElement = panel.contentElement.createChild('div');

    this.calculator = new NetworkTransferTimeCalculator();

    this.splitWidget = new UI.SplitWidget.SplitWidget(true, false, 'networkPanelSplitViewState');
    this.splitWidget.hideMain();
    this.splitWidget.show(panel.contentElement);

    panel.setDefaultFocusedChild(this.filterBar);

    const initialSidebarWidth = 225;
    const splitWidget = new UI.SplitWidget.SplitWidget(true, false, 'networkPanelSidebarState', initialSidebarWidth);
    splitWidget.hideSidebar();
    splitWidget.enableShowModeSaving();
    splitWidget.show(this.element);
    this.sidebarLocation = UI.ViewManager.ViewManager.instance().createTabbedLocation(async () => {
      void UI.ViewManager.ViewManager.instance().showView('network');
      splitWidget.showBoth();
    }, 'network-sidebar', true);
    const tabbedPane = this.sidebarLocation.tabbedPane();
    tabbedPane.setMinimumSize(100, 25);
    tabbedPane.element.classList.add('network-tabbed-pane');
    tabbedPane.element.addEventListener('keydown', event => {
      if (event.key !== Platform.KeyboardUtilities.ESCAPE_KEY) {
        return;
      }
      splitWidget.hideSidebar();
      event.consume();
    });
    const closeSidebar = new UI.Toolbar.ToolbarButton(i18nString(UIStrings.close), 'largeicon-delete');
    closeSidebar.addEventListener(UI.Toolbar.ToolbarButton.Events.Click, () => splitWidget.hideSidebar());
    tabbedPane.rightToolbar().appendToolbarItem(closeSidebar);
    splitWidget.setSidebarWidget(tabbedPane);
    splitWidget.setMainWidget(panel);
    splitWidget.setDefaultFocusedChild(panel);
    this.setDefaultFocusedChild(splitWidget);

    this.progressBarContainer = document.createElement('div');

    this.networkLogView =
        new NetworkLogView(this.filterBar, this.progressBarContainer, this.networkLogLargeRowsSetting);
    this.splitWidget.setSidebarWidget(this.networkLogView);
    this.fileSelectorElement =
        (UI.UIUtils.createFileSelectorElement(this.networkLogView.onLoadFromFile.bind(this.networkLogView)) as
         HTMLElement);
    panel.element.appendChild(this.fileSelectorElement);

    this.detailsWidget = new UI.Widget.VBox();
    this.detailsWidget.element.classList.add('network-details-view');
    this.splitWidget.setMainWidget(this.detailsWidget);

    this.closeButtonElement = document.createElement('div', {is: 'dt-close-button'});
    this.closeButtonElement.addEventListener('click', async () => {
      const action = UI.ActionRegistry.ActionRegistry.instance().action('network.hide-request-details');
      if (action) {
        await action.execute();
      }
    }, false);
    this.closeButtonElement.style.margin = '0 5px';

    this.networkLogShowOverviewSetting.addChangeListener(this.toggleShowOverview, this);
    this.networkLogLargeRowsSetting.addChangeListener(this.toggleLargerRequests, this);
    this.networkRecordFilmStripSetting.addChangeListener(this.toggleRecordFilmStrip, this);

    this.preserveLogSetting = Common.Settings.Settings.instance().moduleSetting('network_log.preserve-log');
    this.recordLogSetting = Common.Settings.Settings.instance().moduleSetting('network_log.record-log');
    this.recordLogSetting.addChangeListener(({data}) => this.toggleRecord(data));

    this.throttlingSelect = this.createThrottlingConditionsSelect();
    this.setupToolbarButtons(splitWidget);

    this.toggleRecord(this.recordLogSetting.get());
    this.toggleShowOverview();
    this.toggleLargerRequests();
    this.toggleRecordFilmStrip();
    this.updateUI();

    SDK.TargetManager.TargetManager.instance().addModelListener(
        SDK.ResourceTreeModel.ResourceTreeModel, SDK.ResourceTreeModel.Events.WillReloadPage, this.willReloadPage,
        this);
    SDK.TargetManager.TargetManager.instance().addModelListener(
        SDK.ResourceTreeModel.ResourceTreeModel, SDK.ResourceTreeModel.Events.Load, this.load, this);
    this.networkLogView.addEventListener(Events.RequestSelected, this.onRequestSelected, this);
    this.networkLogView.addEventListener(Events.RequestActivated, this.onRequestActivated, this);
    Logs.NetworkLog.NetworkLog.instance().addEventListener(
        Logs.NetworkLog.Events.RequestAdded, this.onUpdateRequest, this);
    Logs.NetworkLog.NetworkLog.instance().addEventListener(
        Logs.NetworkLog.Events.RequestUpdated, this.onUpdateRequest, this);
    Logs.NetworkLog.NetworkLog.instance().addEventListener(Logs.NetworkLog.Events.Reset, this.onNetworkLogReset, this);
  }

  static instance(opts: {
    forceNew: boolean|null,
  } = {forceNew: null}): NetworkPanel {
    const {forceNew} = opts;
    if (!networkPanelInstance || forceNew) {
      networkPanelInstance = new NetworkPanel();
    }

    return networkPanelInstance;
  }

  static revealAndFilter(filters: {
    filterType: NetworkForward.UIFilter.FilterType|null,
    filterValue: string,
  }[]): Promise<void> {
    const panel = NetworkPanel.instance();
    let filterString = '';
    for (const filter of filters) {
      if (filter.filterType) {
        filterString += `${filter.filterType}:${filter.filterValue} `;
      } else {
        filterString += `${filter.filterValue} `;
      }
    }
    panel.networkLogView.setTextFilterValue(filterString);
    return UI.ViewManager.ViewManager.instance().showView('network');
  }

  static async selectAndShowRequest(
      request: SDK.NetworkRequest.NetworkRequest, tab: NetworkForward.UIRequestLocation.UIRequestTabs,
      options?: NetworkForward.UIRequestLocation.FilterOptions): Promise<void> {
    const panel = NetworkPanel.instance();
    await panel.selectAndActivateRequest(request, tab, options);
  }

  throttlingSelectForTest(): UI.Toolbar.ToolbarComboBox {
    return this.throttlingSelect;
  }

  private onWindowChanged(event: Common.EventTarget.EventTargetEvent<PerfUI.TimelineOverviewPane.WindowChangedEvent>):
      void {
    const startTime = Math.max(this.calculator.minimumBoundary(), event.data.startTime / 1000);
    const endTime = Math.min(this.calculator.maximumBoundary(), event.data.endTime / 1000);
    this.networkLogView.setWindow(startTime, endTime);
  }

  private async searchToggleClick(): Promise<void> {
    const action = UI.ActionRegistry.ActionRegistry.instance().action('network.search');
    if (action) {
      await action.execute();
    }
  }

  private setupToolbarButtons(splitWidget: UI.SplitWidget.SplitWidget): void {
    const searchToggle = new UI.Toolbar.ToolbarToggle(i18nString(UIStrings.search), 'largeicon-search');
    function updateSidebarToggle(): void {
      const isSidebarShowing = splitWidget.showMode() !== UI.SplitWidget.ShowMode.OnlyMain;
      searchToggle.setToggled(isSidebarShowing);
      if (!isSidebarShowing) {
        (searchToggle.element as HTMLElement).focus();
      }
    }
    this.panelToolbar.appendToolbarItem(UI.Toolbar.Toolbar.createActionButton(this.toggleRecordAction));
    const clearButton = new UI.Toolbar.ToolbarButton(i18nString(UIStrings.clear), 'largeicon-clear');
    clearButton.addEventListener(
        UI.Toolbar.ToolbarButton.Events.Click, () => Logs.NetworkLog.NetworkLog.instance().reset(true), this);
    this.panelToolbar.appendToolbarItem(clearButton);
    this.panelToolbar.appendSeparator();

    this.panelToolbar.appendToolbarItem(this.filterBar.filterButton());
    updateSidebarToggle();
    splitWidget.addEventListener(UI.SplitWidget.Events.ShowModeChanged, updateSidebarToggle);
    searchToggle.addEventListener(UI.Toolbar.ToolbarButton.Events.Click, () => {
      void this.searchToggleClick();
    });
    this.panelToolbar.appendToolbarItem(searchToggle);
    this.panelToolbar.appendSeparator();

    this.panelToolbar.appendToolbarItem(new UI.Toolbar.ToolbarSettingCheckbox(
        this.preserveLogSetting, i18nString(UIStrings.doNotClearLogOnPageReload), i18nString(UIStrings.preserveLog)));

    this.panelToolbar.appendSeparator();
    const disableCacheCheckbox = new UI.Toolbar.ToolbarSettingCheckbox(
        Common.Settings.Settings.instance().moduleSetting('cacheDisabled'),
        i18nString(UIStrings.disableCacheWhileDevtoolsIsOpen), i18nString(UIStrings.disableCache));
    this.panelToolbar.appendToolbarItem(disableCacheCheckbox);

    this.panelToolbar.appendToolbarItem(this.throttlingSelect);

    const networkConditionsIcon = new IconButton.Icon.Icon();
    networkConditionsIcon.data = {
      iconName: 'network_conditions_icon',
      color: 'rgb(110 110 110)',
      width: '18px',
      height: '18px',
    };
    const networkConditionsButton =
        new UI.Toolbar.ToolbarButton(i18nString(UIStrings.moreNetworkConditions), networkConditionsIcon);
    networkConditionsButton.addEventListener(UI.Toolbar.ToolbarButton.Events.Click, () => {
      void UI.ViewManager.ViewManager.instance().showView('network.config');
    }, this);
    this.panelToolbar.appendToolbarItem(networkConditionsButton);

    this.rightToolbar.appendToolbarItem(new UI.Toolbar.ToolbarItem(this.progressBarContainer));
    this.rightToolbar.appendSeparator();
    this.rightToolbar.appendToolbarItem(new UI.Toolbar.ToolbarSettingToggle(
        this.showSettingsPaneSetting, 'largeicon-settings-gear', i18nString(UIStrings.networkSettings)));

    const settingsToolbarLeft = new UI.Toolbar.Toolbar('', this.settingsPane.element);
    settingsToolbarLeft.makeVertical();
    settingsToolbarLeft.appendToolbarItem(new UI.Toolbar.ToolbarSettingCheckbox(
        this.networkLogLargeRowsSetting, i18nString(UIStrings.showMoreInformationInRequestRows),
        i18nString(UIStrings.useLargeRequestRows)));
    settingsToolbarLeft.appendToolbarItem(new UI.Toolbar.ToolbarSettingCheckbox(
        this.networkLogShowOverviewSetting, i18nString(UIStrings.showOverviewOfNetworkRequests),
        i18nString(UIStrings.showOverview)));

    const settingsToolbarRight = new UI.Toolbar.Toolbar('', this.settingsPane.element);
    settingsToolbarRight.makeVertical();
    settingsToolbarRight.appendToolbarItem(new UI.Toolbar.ToolbarSettingCheckbox(
        Common.Settings.Settings.instance().moduleSetting('network.group-by-frame'),
        i18nString(UIStrings.groupRequestsByTopLevelRequest), i18nString(UIStrings.groupByFrame)));
    settingsToolbarRight.appendToolbarItem(new UI.Toolbar.ToolbarSettingCheckbox(
        this.networkRecordFilmStripSetting, i18nString(UIStrings.captureScreenshotsWhenLoadingA),
        i18nString(UIStrings.captureScreenshots)));

    this.panelToolbar.appendSeparator();
    const importHarButton = new UI.Toolbar.ToolbarButton(i18nString(UIStrings.importHarFile), 'largeicon-load');
    importHarButton.addEventListener(
        UI.Toolbar.ToolbarButton.Events.Click, () => this.fileSelectorElement.click(), this);
    this.panelToolbar.appendToolbarItem(importHarButton);
    const exportHarButton = new UI.Toolbar.ToolbarButton(i18nString(UIStrings.exportHar), 'largeicon-download');
    exportHarButton.addEventListener(UI.Toolbar.ToolbarButton.Events.Click, _event => {
      void this.networkLogView.exportAll();
    }, this);
    this.panelToolbar.appendToolbarItem(exportHarButton);
  }

  private updateSettingsPaneVisibility(): void {
    this.settingsPane.element.classList.toggle('hidden', !this.showSettingsPaneSetting.get());
  }

  private createThrottlingConditionsSelect(): UI.Toolbar.ToolbarComboBox {
    const toolbarItem = new UI.Toolbar.ToolbarComboBox(null, i18nString(UIStrings.throttling));
    toolbarItem.setMaxWidth(160);
    MobileThrottling.ThrottlingManager.throttlingManager().decorateSelectWithNetworkThrottling(
        toolbarItem.selectElement());
    return toolbarItem;
  }

  toggleRecord(toggled: boolean): void {
    this.toggleRecordAction.setToggled(toggled);
    if (this.recordLogSetting.get() !== toggled) {
      this.recordLogSetting.set(toggled);
    }

    this.networkLogView.setRecording(toggled);
    if (!toggled && this.filmStripRecorder) {
      this.filmStripRecorder.stopRecording(this.filmStripAvailable.bind(this));
    }
  }

  private filmStripAvailable(filmStripModel: SDK.FilmStripModel.FilmStripModel|null): void {
    if (!filmStripModel) {
      return;
    }
    const calculator = this.networkLogView.timeCalculator();
    if (this.filmStripView) {
      this.filmStripView.setModel(
          filmStripModel, calculator.minimumBoundary() * 1000, calculator.boundarySpan() * 1000);
    }
    this.networkOverview.setFilmStripModel(filmStripModel);
    const timestamps = filmStripModel.frames().map(mapTimestamp);

    function mapTimestamp(frame: SDK.FilmStripModel.Frame): number {
      return frame.timestamp / 1000;
    }

    this.networkLogView.addFilmStripFrames(timestamps);
  }

  private onNetworkLogReset(event: Common.EventTarget.EventTargetEvent<Logs.NetworkLog.ResetEvent>): void {
    const {clearIfPreserved} = event.data;
    BlockedURLsPane.reset();
    if (!this.preserveLogSetting.get() || clearIfPreserved) {
      this.calculator.reset();
      this.overviewPane.reset();
    }
    if (this.filmStripView) {
      this.resetFilmStripView();
    }
  }

  private willReloadPage(): void {
    if (this.pendingStopTimer) {
      clearTimeout(this.pendingStopTimer);
      delete this.pendingStopTimer;
    }
    if (this.isShowing() && this.filmStripRecorder) {
      this.filmStripRecorder.startRecording();
    }
  }

  private load(): void {
    if (this.filmStripRecorder && this.filmStripRecorder.isRecording()) {
      this.pendingStopTimer = window.setTimeout(this.stopFilmStripRecording.bind(this), displayScreenshotDelay);
    }
  }

  private stopFilmStripRecording(): void {
    if (this.filmStripRecorder) {
      this.filmStripRecorder.stopRecording(this.filmStripAvailable.bind(this));
    }
    delete this.pendingStopTimer;
  }

  private toggleLargerRequests(): void {
    this.updateUI();
  }

  private toggleShowOverview(): void {
    const toggled = this.networkLogShowOverviewSetting.get();
    if (toggled) {
      this.overviewPane.show(this.overviewPlaceholderElement);
    } else {
      this.overviewPane.detach();
    }
    this.doResize();
  }

  private toggleRecordFilmStrip(): void {
    const toggled = this.networkRecordFilmStripSetting.get();
    if (toggled && !this.filmStripRecorder) {
      this.filmStripView = new PerfUI.FilmStripView.FilmStripView();
      this.filmStripView.setMode(PerfUI.FilmStripView.Modes.FrameBased);
      this.filmStripView.element.classList.add('network-film-strip');
      this.filmStripRecorder = new FilmStripRecorder(this.networkLogView.timeCalculator(), this.filmStripView);
      this.filmStripView.show(this.filmStripPlaceholderElement);
      this.filmStripView.addEventListener(PerfUI.FilmStripView.Events.FrameSelected, this.onFilmFrameSelected, this);
      this.filmStripView.addEventListener(PerfUI.FilmStripView.Events.FrameEnter, this.onFilmFrameEnter, this);
      this.filmStripView.addEventListener(PerfUI.FilmStripView.Events.FrameExit, this.onFilmFrameExit, this);
      this.resetFilmStripView();
    }

    if (!toggled && this.filmStripRecorder) {
      if (this.filmStripView) {
        this.filmStripView.detach();
      }
      this.filmStripView = null;
      this.filmStripRecorder = null;
    }
  }

  private resetFilmStripView(): void {
    const reloadShortcut =
        UI.ShortcutRegistry.ShortcutRegistry.instance().shortcutsForAction('inspector_main.reload')[0];

    if (this.filmStripView) {
      this.filmStripView.reset();
      if (reloadShortcut) {
        this.filmStripView.setStatusText(
            i18nString(UIStrings.hitSToReloadAndCaptureFilmstrip, {PH1: reloadShortcut.title()}));
      }
    }
  }

  elementsToRestoreScrollPositionsFor(): Element[] {
    return this.networkLogView.elementsToRestoreScrollPositionsFor();
  }

  wasShown(): void {
    UI.Context.Context.instance().setFlavor(NetworkPanel, this);
    this.registerCSSFiles([networkPanelStyles]);

    // Record the network tool load time after the panel has loaded.
    Host.userMetrics.panelLoaded('network', 'DevTools.Launch.Network');
  }

  willHide(): void {
    UI.Context.Context.instance().setFlavor(NetworkPanel, null);
  }

  revealAndHighlightRequest(request: SDK.NetworkRequest.NetworkRequest): void {
    this.hideRequestPanel();
    if (request) {
      this.networkLogView.revealAndHighlightRequest(request);
    }
  }

  revealAndHighlightRequestWithId(request: NetworkForward.NetworkRequestId.NetworkRequestId): void {
    this.hideRequestPanel();
    if (request) {
      this.networkLogView.revealAndHighlightRequestWithId(request);
    }
  }

  async selectAndActivateRequest(
      request: SDK.NetworkRequest.NetworkRequest, shownTab?: NetworkForward.UIRequestLocation.UIRequestTabs,
      options?: NetworkForward.UIRequestLocation.FilterOptions): Promise<NetworkItemView|null> {
    await UI.ViewManager.ViewManager.instance().showView('network');
    this.networkLogView.selectRequest(request, options);
    this.showRequestPanel(shownTab);
    return this.networkItemView;
  }

  private handleFilterChanged(): void {
    this.hideRequestPanel();
  }

  private onRowSizeChanged(): void {
    this.updateUI();
  }

  private onRequestSelected(event: Common.EventTarget.EventTargetEvent<SDK.NetworkRequest.NetworkRequest|null>): void {
    const request = event.data;
    this.currentRequest = request;
    this.networkOverview.setHighlightedRequest(request);
    this.updateNetworkItemView();
  }

  private onRequestActivated(event: Common.EventTarget.EventTargetEvent<RequestActivatedEvent>): void {
    const {showPanel, tab, takeFocus} = event.data;
    if (showPanel) {
      this.showRequestPanel(tab, takeFocus);
    } else {
      this.hideRequestPanel();
    }
  }

  private showRequestPanel(shownTab?: NetworkForward.UIRequestLocation.UIRequestTabs, takeFocus?: boolean): void {
    if (this.splitWidget.showMode() === UI.SplitWidget.ShowMode.Both && !shownTab && !takeFocus) {
      // If panel is already shown, and we are not forcing a specific tab, return.
      return;
    }
    this.clearNetworkItemView();
    if (this.currentRequest) {
      const networkItemView = this.createNetworkItemView(shownTab);
      if (networkItemView && takeFocus) {
        networkItemView.focus();
      }
    }
    this.updateUI();
  }

  hideRequestPanel(): void {
    this.clearNetworkItemView();
    this.splitWidget.hideMain();
    this.updateUI();
  }

  private updateNetworkItemView(): void {
    if (this.splitWidget.showMode() === UI.SplitWidget.ShowMode.Both) {
      this.clearNetworkItemView();
      this.createNetworkItemView();
      this.updateUI();
    }
  }

  private clearNetworkItemView(): void {
    if (this.networkItemView) {
      this.networkItemView.detach();
      this.networkItemView = null;
    }
  }
  private createNetworkItemView(initialTab?: NetworkForward.UIRequestLocation.UIRequestTabs): NetworkItemView
      |undefined {
    if (!this.currentRequest) {
      return;
    }
    this.networkItemView = new NetworkItemView(this.currentRequest, this.networkLogView.timeCalculator(), initialTab);
    this.networkItemView.leftToolbar().appendToolbarItem(new UI.Toolbar.ToolbarItem(this.closeButtonElement));
    this.networkItemView.show(this.detailsWidget.element);
    this.splitWidget.showBoth();
    return this.networkItemView;
  }

  private updateUI(): void {
    if (this.detailsWidget) {
      this.detailsWidget.element.classList.toggle(
          'network-details-view-tall-header', this.networkLogLargeRowsSetting.get());
    }
    if (this.networkLogView) {
      this.networkLogView.switchViewMode(!this.splitWidget.isResizable());
    }
  }

  appendApplicableItems(this: NetworkPanel, event: Event, contextMenu: UI.ContextMenu.ContextMenu, target: Object):
      void {
    function reveal(this: NetworkPanel, request: SDK.NetworkRequest.NetworkRequest): void {
      void UI.ViewManager.ViewManager.instance()
          .showView('network')
          .then(this.networkLogView.resetFilter.bind(this.networkLogView))
          .then(this.revealAndHighlightRequest.bind(this, request));
    }

    function appendRevealItem(this: NetworkPanel, request: SDK.NetworkRequest.NetworkRequest): void {
      contextMenu.revealSection().appendItem(i18nString(UIStrings.revealInNetworkPanel), reveal.bind(this, request));
    }
    if ((event.target as Node).isSelfOrDescendant(this.element)) {
      return;
    }

    if (target instanceof SDK.Resource.Resource) {
      const resource = (target as SDK.Resource.Resource);
      if (resource.request) {
        appendRevealItem.call(this, resource.request);
      }
      return;
    }
    if (target instanceof Workspace.UISourceCode.UISourceCode) {
      const uiSourceCode = (target as Workspace.UISourceCode.UISourceCode);
      const resource = Bindings.ResourceUtils.resourceForURL(uiSourceCode.url());
      if (resource && resource.request) {
        appendRevealItem.call(this, resource.request);
      }
      return;
    }

    if (!(target instanceof SDK.NetworkRequest.NetworkRequest)) {
      return;
    }
    const request = (target as SDK.NetworkRequest.NetworkRequest);
    if (this.networkItemView && this.networkItemView.isShowing() && this.networkItemView.request() === request) {
      return;
    }

    appendRevealItem.call(this, request);
  }

  private onFilmFrameSelected(event: Common.EventTarget.EventTargetEvent<number>): void {
    const timestamp = event.data;
    this.overviewPane.setWindowTimes(0, timestamp);
  }

  private onFilmFrameEnter(event: Common.EventTarget.EventTargetEvent<number>): void {
    const timestamp = event.data;
    this.networkOverview.selectFilmStripFrame(timestamp);
    this.networkLogView.selectFilmStripFrame(timestamp / 1000);
  }

  private onFilmFrameExit(): void {
    this.networkOverview.clearFilmStripFrame();
    this.networkLogView.clearFilmStripFrame();
  }

  private onUpdateRequest(event: Common.EventTarget.EventTargetEvent<SDK.NetworkRequest.NetworkRequest>): void {
    const request = event.data;
    this.calculator.updateBoundaries(request);
    // FIXME: Unify all time units across the frontend!
    this.overviewPane.setBounds(this.calculator.minimumBoundary() * 1000, this.calculator.maximumBoundary() * 1000);
    this.networkOverview.updateRequest(request);
    this.overviewPane.scheduleUpdate();
  }

  resolveLocation(locationName: string): UI.View.ViewLocation|null {
    if (locationName === 'network-sidebar') {
      return this.sidebarLocation;
    }
    return null;
  }
}

export const displayScreenshotDelay = 1000;

let contextMenuProviderInstance: ContextMenuProvider;

export class ContextMenuProvider implements UI.ContextMenu.Provider {
  static instance(opts: {
    forceNew: boolean|null,
  } = {forceNew: null}): ContextMenuProvider {
    const {forceNew} = opts;
    if (!contextMenuProviderInstance || forceNew) {
      contextMenuProviderInstance = new ContextMenuProvider();
    }

    return contextMenuProviderInstance;
  }
  appendApplicableItems(event: Event, contextMenu: UI.ContextMenu.ContextMenu, target: Object): void {
    NetworkPanel.instance().appendApplicableItems(event, contextMenu, target);
  }
}
let requestRevealerInstance: RequestRevealer;
export class RequestRevealer implements Common.Revealer.Revealer {
  static instance(opts: {
    forceNew: boolean|null,
  } = {forceNew: null}): RequestRevealer {
    const {forceNew} = opts;
    if (!requestRevealerInstance || forceNew) {
      requestRevealerInstance = new RequestRevealer();
    }

    return requestRevealerInstance;
  }

  reveal(request: Object): Promise<void> {
    if (!(request instanceof SDK.NetworkRequest.NetworkRequest)) {
      return Promise.reject(new Error('Internal error: not a network request'));
    }
    const panel = NetworkPanel.instance();
    return UI.ViewManager.ViewManager.instance().showView('network').then(
        panel.revealAndHighlightRequest.bind(panel, request));
  }
}

let requestIdRevealerInstance: RequestIdRevealer;
export class RequestIdRevealer implements Common.Revealer.Revealer {
  static instance(opts: {
    forceNew: boolean|null,
  } = {forceNew: null}): RequestIdRevealer {
    const {forceNew} = opts;
    if (!requestIdRevealerInstance || forceNew) {
      requestIdRevealerInstance = new RequestIdRevealer();
    }

    return requestIdRevealerInstance;
  }

  reveal(requestId: Object): Promise<void> {
    if (!(requestId instanceof NetworkForward.NetworkRequestId.NetworkRequestId)) {
      return Promise.reject(new Error('Internal error: not a network request ID'));
    }
    const panel = NetworkPanel.instance();
    return UI.ViewManager.ViewManager.instance().showView('network').then(
        panel.revealAndHighlightRequestWithId.bind(panel, requestId));
  }
}

let networkLogWithFilterRevealerInstance: NetworkLogWithFilterRevealer;
export class NetworkLogWithFilterRevealer implements Common.Revealer.Revealer {
  static instance(opts: {
    forceNew: boolean|null,
  } = {forceNew: null}): NetworkLogWithFilterRevealer {
    const {forceNew} = opts;
    if (!networkLogWithFilterRevealerInstance || forceNew) {
      networkLogWithFilterRevealerInstance = new NetworkLogWithFilterRevealer();
    }

    return networkLogWithFilterRevealerInstance;
  }

  reveal(request: Object): Promise<void> {
    if (!(request instanceof NetworkForward.UIFilter.UIRequestFilter)) {
      return Promise.reject(new Error('Internal error: not a UIRequestFilter'));
    }
    return NetworkPanel.revealAndFilter(request.filters);
  }
}

export class FilmStripRecorder implements SDK.TracingManager.TracingManagerClient {
  private tracingManager: SDK.TracingManager.TracingManager|null;
  private resourceTreeModel: SDK.ResourceTreeModel.ResourceTreeModel|null;
  private readonly timeCalculator: NetworkTimeCalculator;
  private readonly filmStripView: PerfUI.FilmStripView.FilmStripView;
  private tracingModel: SDK.TracingModel.TracingModel|null;
  private callback: ((arg0: SDK.FilmStripModel.FilmStripModel|null) => void)|null;

  constructor(timeCalculator: NetworkTimeCalculator, filmStripView: PerfUI.FilmStripView.FilmStripView) {
    this.tracingManager = null;
    this.resourceTreeModel = null;
    this.timeCalculator = timeCalculator;
    this.filmStripView = filmStripView;
    this.tracingModel = null;
    this.callback = null;
  }

  traceEventsCollected(events: SDK.TracingManager.EventPayload[]): void {
    if (this.tracingModel) {
      this.tracingModel.addEvents(events);
    }
  }

  tracingComplete(): void {
    if (!this.tracingModel || !this.tracingManager) {
      return;
    }
    this.tracingModel.tracingComplete();
    this.tracingManager = null;
    if (this.callback) {
      this.callback(
          new SDK.FilmStripModel.FilmStripModel(this.tracingModel, this.timeCalculator.minimumBoundary() * 1000));
    }
    this.callback = null;
    if (this.resourceTreeModel) {
      this.resourceTreeModel.resumeReload();
    }
    this.resourceTreeModel = null;
  }

  tracingBufferUsage(): void {
  }

  eventsRetrievalProgress(_progress: number): void {
  }

  startRecording(): void {
    this.filmStripView.reset();
    this.filmStripView.setStatusText(i18nString(UIStrings.recordingFrames));
    const tracingManagers = SDK.TargetManager.TargetManager.instance().models(SDK.TracingManager.TracingManager);
    if (this.tracingManager || !tracingManagers.length) {
      return;
    }

    this.tracingManager = tracingManagers[0];
    if (!this.tracingManager) {
      return;
    }
    this.resourceTreeModel = this.tracingManager.target().model(SDK.ResourceTreeModel.ResourceTreeModel);
    if (this.tracingModel) {
      this.tracingModel.dispose();
    }
    this.tracingModel = new SDK.TracingModel.TracingModel(new Bindings.TempFile.TempFileBackingStorage());
    void this.tracingManager.start(this, '-*,disabled-by-default-devtools.screenshot', '');

    Host.userMetrics.actionTaken(Host.UserMetrics.Action.FilmStripStartedRecording);
  }

  isRecording(): boolean {
    return Boolean(this.tracingManager);
  }

  stopRecording(callback: (arg0: SDK.FilmStripModel.FilmStripModel|null) => void): void {
    if (!this.tracingManager) {
      return;
    }

    this.tracingManager.stop();
    if (this.resourceTreeModel) {
      this.resourceTreeModel.suspendReload();
    }
    this.callback = callback;
    this.filmStripView.setStatusText(i18nString(UIStrings.fetchingFrames));
  }
}

let networkActionDelegateInstance: ActionDelegate;

export class ActionDelegate implements UI.ActionRegistration.ActionDelegate {
  static instance(opts: {
    forceNew: boolean|null,
  }|undefined = {forceNew: null}): ActionDelegate {
    const {forceNew} = opts;
    if (!networkActionDelegateInstance || forceNew) {
      networkActionDelegateInstance = new ActionDelegate();
    }
    return networkActionDelegateInstance;
  }

  handleAction(context: UI.Context.Context, actionId: string): boolean {
    const panel = UI.Context.Context.instance().flavor(NetworkPanel);
    console.assert(Boolean(panel && panel instanceof NetworkPanel));
    if (!panel) {
      return false;
    }
    switch (actionId) {
      case 'network.toggle-recording': {
        panel.toggleRecord(!panel.recordLogSetting.get());
        return true;
      }
      case 'network.hide-request-details': {
        if (!panel.networkItemView) {
          return false;
        }
        panel.hideRequestPanel();
        panel.networkLogView.resetFocus();
        return true;
      }
      case 'network.search': {
        const selection = UI.InspectorView.InspectorView.instance().element.window().getSelection();
        if (selection) {
          let queryCandidate = '';
          if (selection.rangeCount) {
            queryCandidate = selection.toString().replace(/\r?\n.*/, '');
          }
          void SearchNetworkView.openSearch(queryCandidate);
          return true;
        }
      }
    }
    return false;
  }
}

let requestLocationRevealerInstance: RequestLocationRevealer;

export class RequestLocationRevealer implements Common.Revealer.Revealer {
  static instance(opts: {
    forceNew: boolean|null,
  }|undefined = {forceNew: null}): RequestLocationRevealer {
    const {forceNew} = opts;
    if (!requestLocationRevealerInstance || forceNew) {
      requestLocationRevealerInstance = new RequestLocationRevealer();
    }
    return requestLocationRevealerInstance;
  }

  async reveal(match: Object): Promise<void> {
    const location = match as NetworkForward.UIRequestLocation.UIRequestLocation;
    const view =
        await NetworkPanel.instance().selectAndActivateRequest(location.request, location.tab, location.filterOptions);
    if (!view) {
      return;
    }
    if (location.searchMatch) {
      await view.revealResponseBody(location.searchMatch.lineNumber);
    }
    if (location.header) {
      view.revealHeader(location.header.section, location.header.header?.name);
    }
  }
}

let searchNetworkViewInstance: SearchNetworkView;

export class SearchNetworkView extends Search.SearchView.SearchView {
  private constructor() {
    super('network');
  }

  static instance(opts: {
    forceNew: boolean|null,
  } = {forceNew: null}): SearchNetworkView {
    const {forceNew} = opts;
    if (!searchNetworkViewInstance || forceNew) {
      searchNetworkViewInstance = new SearchNetworkView();
    }

    return searchNetworkViewInstance;
  }

  static async openSearch(query: string, searchImmediately?: boolean): Promise<Search.SearchView.SearchView> {
    await UI.ViewManager.ViewManager.instance().showView('network.search-network-tab');
    const searchView = SearchNetworkView.instance();
    void searchView.toggle(query, Boolean(searchImmediately));
    return searchView;
  }

  createScope(): Search.SearchConfig.SearchScope {
    return new NetworkSearchScope();
  }
}