// Copyright 2024 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

import '../../../ui/kit/kit.js';
import '../../../ui/components/menus/menus.js';

import * as Common from '../../../core/common/common.js';
import * as i18n from '../../../core/i18n/i18n.js';
import * as SDK from '../../../core/sdk/sdk.js';
import type * as Menus from '../../../ui/components/menus/menus.js';
import * as UI from '../../../ui/legacy/legacy.js';
import * as Lit from '../../../ui/lit/lit.js';
import * as VisualLogging from '../../../ui/visual_logging/visual_logging.js';
import * as MobileThrottling from '../../mobile_throttling/mobile_throttling.js';

import cpuThrottlingSelectorStyles from './cpuThrottlingSelector.css.js';

const {render, html} = Lit;

const UIStrings = {
  /**
   * @description Text label for a selection box showing which CPU throttling option is applied.
   * @example {No throttling} PH1
   */
  cpu: 'CPU: {PH1}',
  /**
   * @description Text label for a selection box showing which CPU throttling option is applied.
   * @example {No throttling} PH1
   */
  cpuThrottling: 'CPU throttling: {PH1}',
  /**
   * @description Text label for a selection box showing that a specific option is recommended.
   * @example {4x slowdown} PH1
   */
  recommendedThrottling: '{PH1} – recommended',
  /**
   * @description Text for why user should change a throttling setting.
   */
  recommendedThrottlingReason: 'Consider changing setting to simulate real user environments',
  /**
   * @description Text to prompt the user to run the CPU calibration process.
   */
  calibrate: 'Calibrate…',
  /**
   * @description Text to prompt the user to re-run the CPU calibration process.
   */
  recalibrate: 'Recalibrate…',
  /**
   * @description Label shown above a list of CPU calibration preset options.
   */
  labelCalibratedPresets: 'Calibrated presets',
} as const;

const str_ = i18n.i18n.registerUIStrings('panels/timeline/components/CPUThrottlingSelector.ts', UIStrings);
const i18nString = i18n.i18n.getLocalizedString.bind(undefined, str_);

interface CPUThrottlingGroup {
  name: string;
  items: SDK.CPUThrottlingManager.CPUThrottlingOption[];
  showCustomAddOption?: boolean;
}

interface ViewInput {
  recommendedOption: SDK.CPUThrottlingManager.CPUThrottlingOption|null;
  currentOption: SDK.CPUThrottlingManager.CPUThrottlingOption;
  groups: CPUThrottlingGroup[];
  throttling: SDK.CPUThrottlingManager.CalibratedCPUThrottling;
  onMenuItemSelected: (event: Menus.SelectMenu.SelectMenuItemSelectedEvent) => void;
  onCalibrateClick: () => void;
}

export const DEFAULT_VIEW = (input: ViewInput, _output: undefined, target: HTMLElement): void => {
  let recommendedInfoEl;
  if (input.recommendedOption && input.currentOption === SDK.CPUThrottlingManager.NoThrottlingOption) {
    recommendedInfoEl = html`<devtools-icon
        title=${i18nString(UIStrings.recommendedThrottlingReason)}
        name=info></devtools-icon>`;
  }

  const selectionTitle = input.currentOption.title();
  const hasCalibratedOnce = input.throttling.low || input.throttling.mid;
  const calibrationLabel = hasCalibratedOnce ? i18nString(UIStrings.recalibrate) : i18nString(UIStrings.calibrate);

  // clang-format off
  /* eslint-disable @devtools/no-deprecated-component-usages */
  const template = html`
    <style>${cpuThrottlingSelectorStyles}</style>
    <devtools-select-menu
          @selectmenuselected=${input.onMenuItemSelected}
          .showDivider=${true}
          .showArrow=${true}
          .sideButton=${false}
          .showSelectedItem=${true}
          .jslogContext=${'cpu-throttling'}
          .buttonTitle=${i18nString(UIStrings.cpu, {PH1: selectionTitle})}
          .title=${i18nString(UIStrings.cpuThrottling, {PH1: selectionTitle})}
        >
        ${input.groups.map(group => {
          return html`
            <devtools-menu-group .name=${group.name} .title=${group.name}>
              ${group.items.map(option => {
                const title = option === input.recommendedOption ? i18nString(UIStrings.recommendedThrottling, {PH1: option.title()}) : option.title();
                const rate = option.rate();
                return html`
                  <devtools-menu-item
                    .value=${option.calibratedDeviceType ?? rate}
                    .selected=${input.currentOption === option}
                    .disabled=${rate === 0}
                    .title=${title}
                    jslog=${VisualLogging.item(option.jslogContext).track({click: true})}
                  >
                    ${title}
                  </devtools-menu-item>
                `;
              })}
              ${group.name === 'Calibrated presets' ? html`<devtools-menu-item
                .value=${-1 /* This won't be displayed unless it has some value. */}
                .title=${calibrationLabel}
                jslog=${VisualLogging.action('cpu-throttling-selector-calibrate').track({click: true})}
                @click=${input.onCalibrateClick}
              >
                ${calibrationLabel}
              </devtools-menu-item>` : Lit.nothing}
            </devtools-menu-group>`;
        })}
    </devtools-select-menu>
    ${recommendedInfoEl}
  `;
  // clang-format on
  render(template, target);
};

type View = typeof DEFAULT_VIEW;

export class CPUThrottlingSelector extends UI.Widget.Widget {
  #currentOption: SDK.CPUThrottlingManager.CPUThrottlingOption;
  #recommendedOption: SDK.CPUThrottlingManager.CPUThrottlingOption|null = null;
  #groups: CPUThrottlingGroup[] = [];
  #calibratedThrottlingSetting: Common.Settings.Setting<SDK.CPUThrottlingManager.CalibratedCPUThrottling>;
  readonly #view: View;

  constructor(element?: HTMLElement, view: View = DEFAULT_VIEW) {
    super(element);
    this.#currentOption = SDK.CPUThrottlingManager.CPUThrottlingManager.instance().cpuThrottlingOption();
    this.#calibratedThrottlingSetting =
        Common.Settings.Settings.instance().createSetting<SDK.CPUThrottlingManager.CalibratedCPUThrottling>(
            'calibrated-cpu-throttling', {}, Common.Settings.SettingStorageType.GLOBAL);
    this.#resetGroups();
    this.#view = view;
  }

  set recommendedOption(recommendedOption: SDK.CPUThrottlingManager.CPUThrottlingOption|null) {
    this.#recommendedOption = recommendedOption;
    this.requestUpdate();
  }

  override wasShown(): void {
    super.wasShown();
    SDK.CPUThrottlingManager.CPUThrottlingManager.instance().addEventListener(
        SDK.CPUThrottlingManager.Events.RATE_CHANGED, this.#onOptionChange, this);
    this.#calibratedThrottlingSetting.addChangeListener(this.#onCalibratedSettingChanged, this);
    this.#onOptionChange();
  }

  override willHide(): void {
    super.willHide();
    this.#calibratedThrottlingSetting.removeChangeListener(this.#onCalibratedSettingChanged, this);
    SDK.CPUThrottlingManager.CPUThrottlingManager.instance().removeEventListener(
        SDK.CPUThrottlingManager.Events.RATE_CHANGED, this.#onOptionChange, this);
  }

  #onOptionChange(): void {
    this.#currentOption = SDK.CPUThrottlingManager.CPUThrottlingManager.instance().cpuThrottlingOption();

    this.requestUpdate();
  }

  #onCalibratedSettingChanged(): void {
    this.#resetGroups();
    this.requestUpdate();
  }

  #onMenuItemSelected(event: Menus.SelectMenu.SelectMenuItemSelectedEvent): void {
    let option;
    if (typeof event.itemValue === 'string') {
      if (event.itemValue === 'low-tier-mobile') {
        option = SDK.CPUThrottlingManager.CalibratedLowTierMobileThrottlingOption;
      } else if (event.itemValue === 'mid-tier-mobile') {
        option = SDK.CPUThrottlingManager.CalibratedMidTierMobileThrottlingOption;
      }
    } else {
      const rate = Number(event.itemValue);
      option = MobileThrottling.ThrottlingPresets.ThrottlingPresets.cpuThrottlingPresets.find(
          option => !option.calibratedDeviceType && option.rate() === rate);
    }

    if (option) {
      MobileThrottling.ThrottlingManager.throttlingManager().setCPUThrottlingOption(option);
    }
  }

  #onCalibrateClick(): void {
    void Common.Revealer.reveal(this.#calibratedThrottlingSetting);
  }

  #resetGroups(): void {
    this.#groups = [
      {
        name: '',
        items: MobileThrottling.ThrottlingPresets.ThrottlingPresets.cpuThrottlingPresets.filter(
            option => !option.calibratedDeviceType),
      },
      {
        name: i18nString(UIStrings.labelCalibratedPresets),
        items: MobileThrottling.ThrottlingPresets.ThrottlingPresets.cpuThrottlingPresets.filter(
            option => option.calibratedDeviceType),
      },
    ];
  }

  override async performUpdate(): Promise<void> {
    const input: ViewInput = {
      recommendedOption: this.#recommendedOption,
      currentOption: this.#currentOption,
      groups: this.#groups,
      throttling: this.#calibratedThrottlingSetting.get(),
      onMenuItemSelected: this.#onMenuItemSelected.bind(this),
      onCalibrateClick: this.#onCalibrateClick.bind(this),
    };
    this.#view(input, undefined, this.contentElement);
  }
}