// Copyright 2014 The Chromium Authors
// 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 Bindings from '../../models/bindings/bindings.js';
import type * as Workspace from '../../models/workspace/workspace.js';
import * as UI from '../../ui/legacy/legacy.js';
import {Directives, html, type LitTemplate, nothing, render} from '../../ui/lit/lit.js';
import * as VisualLogging from '../../ui/visual_logging/visual_logging.js';

import mediaQueryInspectorStyles from './mediaQueryInspector.css.js';

const UIStrings = {
  /**
   * @description A context menu item/command in the Media Query Inspector of the Device Toolbar.
   * Takes the user to the source code where this media query actually came from.
   */
  revealInSourceCode: 'Reveal in source code',
} as const;
const str_ = i18n.i18n.registerUIStrings('panels/emulation/MediaQueryInspector.ts', UIStrings);
const i18nString = i18n.i18n.getLocalizedString.bind(undefined, str_);

const {classMap} = Directives;

export interface ViewInput {
  zoomFactor: number;
  markers: Map<Section, MediaQueryMarker[]>;
  onMediaQueryClicked: (model: MediaQueryUIModel) => void;
  onContextMenu: (event: Event, locations: SDK.CSSModel.CSSLocation[]) => void;
}

export interface MediaQueryMarker {
  active: boolean;
  model: MediaQueryUIModel;
  locations: SDK.CSSModel.CSSLocation[];
}

export const DEFAULT_VIEW = (input: ViewInput, _output: object, target: HTMLElement): void => {
  const createBarClassMap = (marker: MediaQueryMarker): Record<string, boolean> => ({
    'media-inspector-bar': true,
    'media-inspector-marker-inactive': !marker.active,
  });
  // clang-format off
  render(html`
    <style>${mediaQueryInspectorStyles}</style>
    <div class='media-inspector-view'>
    ${input.markers.entries().map(([section, markers]) => html`
      <div class='media-inspector-marker-container'>
        ${markers.map(marker => html`
          <div
              class=${classMap(createBarClassMap(marker))}
              @click=${() => input.onMediaQueryClicked(marker.model)}
              @contextmenu=${(event: Event) => input.onContextMenu(event, marker.locations)}
          >
            ${section === Section.MAX
              ? renderMaxSection(input.zoomFactor, marker.model)
              : section === Section.MIN_MAX
                ? renderMinMaxSection(input.zoomFactor, marker.model)
                : renderMinSection(input.zoomFactor, marker.model)}
          </div>
        `)}
      </div>
    `).toArray()}
    </div>`, target);
  // clang-format on
};

function renderMaxSection(zoomFactor: number, model: MediaQueryUIModel): LitTemplate {
  // clang-format off
  return html`
    <div class='media-inspector-marker-spacer'></div>
    <div
        class='media-inspector-marker media-inspector-marker-max-width'
        style=${'width: ' + model.maxWidthValue(zoomFactor) + 'px'}
        title=${model.mediaText()}
    >
      ${renderLabel(model.maxWidthExpression(), false, false)}
      ${renderLabel(model.maxWidthExpression(), true, true)}
    </div>
    <div class='media-inspector-marker-spacer'></div>
  `;
  // clang-format on
}

function renderMinMaxSection(zoomFactor: number, model: MediaQueryUIModel): LitTemplate {
  const width = (model.maxWidthValue(zoomFactor) - model.minWidthValue(zoomFactor)) * 0.5;
  // clang-format off
  return html`
    <div class='media-inspector-marker-spacer'></div>
    <div
        class='media-inspector-marker media-inspector-marker-min-max-width'
        style=${'width: ' + width + 'px'}
        title=${model.mediaText()}
    >
      ${renderLabel(model.maxWidthExpression(), true, false)}
      ${renderLabel(model.minWidthExpression(), false, true)}
    </div>
    <div class='media-inspector-marker-spacer' style=${'flex: 0 0 ' + model.minWidthValue(zoomFactor) + 'px'}></div>
    <div
        class='media-inspector-marker media-inspector-marker-min-max-width'
        style=${'width: ' + width + 'px'}
        title=${model.mediaText()}
    >
      ${renderLabel(model.minWidthExpression(), true, false)}
      ${renderLabel(model.maxWidthExpression(), false, true)}
    </div>
    <div class='media-inspector-marker-spacer'></div>
  `;
  // clang-format on
}

function renderMinSection(zoomFactor: number, model: MediaQueryUIModel): LitTemplate {
  // clang-format off
  return html`
    <div
        class='media-inspector-marker media-inspector-marker-min-width media-inspector-marker-min-width-left'
        title=${model.mediaText()}
    >${renderLabel(model.minWidthExpression(), false, false)}</div>
    <div class='media-inspector-marker-spacer' style=${'flex: 0 0 ' + model.minWidthValue(zoomFactor) + 'px'}></div>
    <div
        class='media-inspector-marker media-inspector-marker-min-width media-inspector-marker-min-width-right'
        title=${model.mediaText()}
    >${renderLabel(model.minWidthExpression(), true, true)}</div>
  `;
  // clang-format on
}

function renderLabel(
    expression: SDK.CSSMedia.CSSMediaQueryExpression|null, atLeft: boolean, leftAlign: boolean): LitTemplate {
  if (!expression) {
    return nothing;
  }

  const containerClassMap = {
    'media-inspector-marker-label-container': true,
    'media-inspector-marker-label-container-left': atLeft,
    'media-inspector-marker-label-container-right': !atLeft
  };
  const labelClassMap = {
    'media-inspector-marker-label': true,
    'media-inspector-label-left': leftAlign,
    'media-inspector-label-right': !leftAlign
  };

  // clang-format off
  return html`
    <div class=${classMap(containerClassMap)}>
      <span class=${classMap(labelClassMap)}>${expression.value()}${expression.unit()}</span>
    </div>
  `;
  // clang-format on
}

export class MediaQueryInspector extends UI.Widget.Widget implements
    SDK.TargetManager.SDKModelObserver<SDK.CSSModel.CSSModel> {
  private readonly view: typeof DEFAULT_VIEW;
  private readonly mediaThrottler: Common.Throttler.Throttler;
  private readonly getWidthCallback: () => number;
  private readonly setWidthCallback: (arg0: number) => void;
  private scale: number;
  private cssModel?: SDK.CSSModel.CSSModel;
  private cachedQueryModels?: MediaQueryUIModel[];

  constructor(
      getWidthCallback: () => number, setWidthCallback: (arg0: number) => void,
      mediaThrottler: Common.Throttler.Throttler, view = DEFAULT_VIEW) {
    super({
      jslog: `${VisualLogging.mediaInspectorView().track({click: true})}`,
      useShadowDom: true,
    });
    this.view = view;
    this.mediaThrottler = mediaThrottler;

    this.getWidthCallback = getWidthCallback;
    this.setWidthCallback = setWidthCallback;
    this.scale = 1;

    SDK.TargetManager.TargetManager.instance().observeModels(SDK.CSSModel.CSSModel, this);
    UI.ZoomManager.ZoomManager.instance().addEventListener(
        UI.ZoomManager.Events.ZOOM_CHANGED, this.requestUpdate.bind(this), this);
  }

  modelAdded(cssModel: SDK.CSSModel.CSSModel): void {
    // FIXME: adapt this to multiple targets.
    if (cssModel.target() !== SDK.TargetManager.TargetManager.instance().primaryPageTarget()) {
      return;
    }
    this.cssModel = cssModel;
    this.cssModel.addEventListener(SDK.CSSModel.Events.StyleSheetAdded, this.scheduleMediaQueriesUpdate, this);
    this.cssModel.addEventListener(SDK.CSSModel.Events.StyleSheetRemoved, this.scheduleMediaQueriesUpdate, this);
    this.cssModel.addEventListener(SDK.CSSModel.Events.StyleSheetChanged, this.scheduleMediaQueriesUpdate, this);
    this.cssModel.addEventListener(SDK.CSSModel.Events.MediaQueryResultChanged, this.scheduleMediaQueriesUpdate, this);
  }

  modelRemoved(cssModel: SDK.CSSModel.CSSModel): void {
    if (cssModel !== this.cssModel) {
      return;
    }
    this.cssModel.removeEventListener(SDK.CSSModel.Events.StyleSheetAdded, this.scheduleMediaQueriesUpdate, this);
    this.cssModel.removeEventListener(SDK.CSSModel.Events.StyleSheetRemoved, this.scheduleMediaQueriesUpdate, this);
    this.cssModel.removeEventListener(SDK.CSSModel.Events.StyleSheetChanged, this.scheduleMediaQueriesUpdate, this);
    this.cssModel.removeEventListener(
        SDK.CSSModel.Events.MediaQueryResultChanged, this.scheduleMediaQueriesUpdate, this);
    delete this.cssModel;
  }

  setAxisTransform(scale: number): void {
    if (Math.abs(this.scale - scale) < 1e-8) {
      return;
    }
    this.scale = scale;
    this.performUpdate();
  }

  private onMediaQueryClicked(model: MediaQueryUIModel): void {
    const modelMaxWidth = model.maxWidthExpression();
    const modelMinWidth = model.minWidthExpression();

    if (model.section() === Section.MAX) {
      this.setWidthCallback(modelMaxWidth ? modelMaxWidth.computedLength() || 0 : 0);
      return;
    }
    if (model.section() === Section.MIN) {
      this.setWidthCallback(modelMinWidth ? modelMinWidth.computedLength() || 0 : 0);
      return;
    }
    const currentWidth = this.getWidthCallback();
    if (modelMinWidth && currentWidth !== modelMinWidth.computedLength()) {
      this.setWidthCallback(modelMinWidth.computedLength() || 0);
    } else {
      this.setWidthCallback(modelMaxWidth ? modelMaxWidth.computedLength() || 0 : 0);
    }
  }

  private onContextMenu(event: Event, locations: SDK.CSSModel.CSSLocation[]): void {
    if (!this.cssModel?.isEnabled()) {
      return;
    }

    const uiLocations = new Map<string, Workspace.UISourceCode.UILocation>();
    for (let i = 0; i < locations.length; ++i) {
      const uiLocation =
          Bindings.CSSWorkspaceBinding.CSSWorkspaceBinding.instance().rawLocationToUILocation(locations[i]);
      if (!uiLocation) {
        continue;
      }
      const descriptor = typeof uiLocation.columnNumber === 'number' ?
          Platform.StringUtilities.sprintf(
              '%s:%d:%d', uiLocation.uiSourceCode.url(), uiLocation.lineNumber + 1, uiLocation.columnNumber + 1) :
          Platform.StringUtilities.sprintf('%s:%d', uiLocation.uiSourceCode.url(), uiLocation.lineNumber + 1);
      uiLocations.set(descriptor, uiLocation);
    }

    const contextMenuItems = [...uiLocations.keys()].sort();
    const contextMenu = new UI.ContextMenu.ContextMenu(event);
    const subMenuItem = contextMenu.defaultSection().appendSubMenuItem(
        i18nString(UIStrings.revealInSourceCode), undefined, 'reveal-in-source-list');
    for (let i = 0; i < contextMenuItems.length; ++i) {
      const title = contextMenuItems[i];
      subMenuItem.defaultSection().appendItem(
          title, this.revealSourceLocation.bind(this, (uiLocations.get(title) as Workspace.UISourceCode.UILocation)),
          {jslogContext: 'reveal-in-source'});
    }
    void contextMenu.show();
  }

  private revealSourceLocation(location: Workspace.UISourceCode.UILocation): void {
    void Common.Revealer.reveal(location);
  }

  private scheduleMediaQueriesUpdate(): void {
    if (!this.isShowing()) {
      return;
    }
    void this.mediaThrottler.schedule(this.refetchMediaQueries.bind(this));
  }

  private refetchMediaQueries(): Promise<void> {
    if (!this.isShowing() || !this.cssModel) {
      return Promise.resolve();
    }

    return this.cssModel.getMediaQueries().then(this.rebuildMediaQueries.bind(this));
  }

  private squashAdjacentEqual(models: MediaQueryUIModel[]): MediaQueryUIModel[] {
    const filtered = [];
    for (let i = 0; i < models.length; ++i) {
      const last = filtered[filtered.length - 1];
      if (!last?.equals(models[i])) {
        filtered.push(models[i]);
      }
    }
    return filtered;
  }

  private rebuildMediaQueries(cssMedias: SDK.CSSMedia.CSSMedia[]): void {
    let queryModels: MediaQueryUIModel[] = [];
    for (let i = 0; i < cssMedias.length; ++i) {
      const cssMedia = cssMedias[i];
      if (!cssMedia.mediaList) {
        continue;
      }
      for (let j = 0; j < cssMedia.mediaList.length; ++j) {
        const mediaQuery = cssMedia.mediaList[j];
        const queryModel = MediaQueryUIModel.createFromMediaQuery(cssMedia, mediaQuery);
        if (queryModel) {
          queryModels.push(queryModel);
        }
      }
    }
    queryModels.sort(compareModels);
    queryModels = this.squashAdjacentEqual(queryModels);

    let allEqual: (boolean|undefined) = this.cachedQueryModels && this.cachedQueryModels.length === queryModels.length;
    for (let i = 0; allEqual && i < queryModels.length; ++i) {
      allEqual = allEqual && this.cachedQueryModels?.[i].equals(queryModels[i]);
    }
    if (allEqual) {
      return;
    }
    this.cachedQueryModels = queryModels;
    this.requestUpdate();

    function compareModels(model1: MediaQueryUIModel, model2: MediaQueryUIModel): number {
      return model1.compareTo(model2);
    }
  }

  private buildMediaQueryMarkers(): MediaQueryMarker[] {
    if (!this.cachedQueryModels) {
      return [];
    }

    const markers: MediaQueryMarker[] = [];
    let lastMarker: MediaQueryMarker|null = null;
    for (const model of this.cachedQueryModels) {
      if (lastMarker?.model.dimensionsEqual(model)) {
        lastMarker.active = lastMarker.active || model.active();
      } else {
        lastMarker = {
          active: model.active(),
          model,
          locations: [],
        };
        markers.push(lastMarker);
      }
      const rawLocation = model.rawLocation();
      if (rawLocation) {
        lastMarker.locations.push(rawLocation);
      }
    }

    return markers;
  }

  private zoomFactor(): number {
    return UI.ZoomManager.ZoomManager.instance().zoomFactor() / this.scale;
  }

  override wasShown(): void {
    super.wasShown();
    this.scheduleMediaQueriesUpdate();
    this.performUpdate();  // Trigger a manual update eagerly, DeviceModeView needs to measure our height.
  }

  override performUpdate(): void {
    const markers = Map.groupBy(this.buildMediaQueryMarkers(), marker => marker.model.section());

    this.view(
        {
          zoomFactor: this.zoomFactor(),
          markers,
          onMediaQueryClicked: this.onMediaQueryClicked.bind(this),
          onContextMenu: this.onContextMenu.bind(this),
        },
        {}, this.contentElement);
  }
}

export const enum Section {
  MAX = 0,
  MIN_MAX = 1,
  MIN = 2,
}

export class MediaQueryUIModel {
  private cssMedia: SDK.CSSMedia.CSSMedia;
  readonly #minWidthExpression: SDK.CSSMedia.CSSMediaQueryExpression|null;
  readonly #maxWidthExpression: SDK.CSSMedia.CSSMediaQueryExpression|null;
  readonly #active: boolean;
  readonly #section: Section;
  #rawLocation?: SDK.CSSModel.CSSLocation|null;
  constructor(
      cssMedia: SDK.CSSMedia.CSSMedia, minWidthExpression: SDK.CSSMedia.CSSMediaQueryExpression|null,
      maxWidthExpression: SDK.CSSMedia.CSSMediaQueryExpression|null, active: boolean) {
    this.cssMedia = cssMedia;
    this.#minWidthExpression = minWidthExpression;
    this.#maxWidthExpression = maxWidthExpression;
    this.#active = active;
    if (maxWidthExpression && !minWidthExpression) {
      this.#section = Section.MAX;
    } else if (minWidthExpression && maxWidthExpression) {
      this.#section = Section.MIN_MAX;
    } else {
      this.#section = Section.MIN;
    }
  }

  static createFromMediaQuery(cssMedia: SDK.CSSMedia.CSSMedia, mediaQuery: SDK.CSSMedia.CSSMediaQuery):
      MediaQueryUIModel|null {
    let maxWidthExpression: SDK.CSSMedia.CSSMediaQueryExpression|null = null;
    let maxWidthPixels: number = Number.MAX_VALUE;
    let minWidthExpression: SDK.CSSMedia.CSSMediaQueryExpression|null = null;
    let minWidthPixels: number = Number.MIN_VALUE;
    const expressions = mediaQuery.expressions();
    if (!expressions) {
      return null;
    }

    for (let i = 0; i < expressions.length; ++i) {
      const expression = expressions[i];
      const feature = expression.feature();
      if (feature.indexOf('width') === -1) {
        continue;
      }
      const pixels = expression.computedLength();
      if (feature.startsWith('max-') && pixels && pixels < maxWidthPixels) {
        maxWidthExpression = expression;
        maxWidthPixels = pixels;
      } else if (feature.startsWith('min-') && pixels && pixels > minWidthPixels) {
        minWidthExpression = expression;
        minWidthPixels = pixels;
      }
    }
    if (minWidthPixels > maxWidthPixels || (!maxWidthExpression && !minWidthExpression)) {
      return null;
    }

    return new MediaQueryUIModel(cssMedia, minWidthExpression, maxWidthExpression, mediaQuery.active());
  }

  equals(other: MediaQueryUIModel): boolean {
    return this.compareTo(other) === 0;
  }

  dimensionsEqual(other: MediaQueryUIModel): boolean {
    const thisMinWidthExpression = this.minWidthExpression();
    const otherMinWidthExpression = other.minWidthExpression();
    const thisMaxWidthExpression = this.maxWidthExpression();
    const otherMaxWidthExpression = other.maxWidthExpression();

    const sectionsEqual = this.section() === other.section();
    // If there isn't an other min width expression, they aren't equal, so the optional chaining operator is safe to use here.
    const minWidthEqual = !thisMinWidthExpression ||
        thisMinWidthExpression.computedLength() === otherMinWidthExpression?.computedLength();
    const maxWidthEqual = !thisMaxWidthExpression ||
        thisMaxWidthExpression.computedLength() === otherMaxWidthExpression?.computedLength();

    return sectionsEqual && minWidthEqual && maxWidthEqual;
  }

  compareTo(other: MediaQueryUIModel): number {
    if (this.section() !== other.section()) {
      return this.section() - other.section();
    }
    if (this.dimensionsEqual(other)) {
      const myLocation = this.rawLocation();
      const otherLocation = other.rawLocation();
      if (!myLocation && !otherLocation) {
        return Platform.StringUtilities.compare(this.mediaText(), other.mediaText());
      }
      if (myLocation && !otherLocation) {
        return 1;
      }
      if (!myLocation && otherLocation) {
        return -1;
      }
      if (this.active() !== other.active()) {
        return this.active() ? -1 : 1;
      }

      if (!myLocation || !otherLocation) {
        // This conditional never runs, because it's dealt with above, but
        // TypeScript can't follow that by this point both myLocation and
        // otherLocation must exist.
        return 0;
      }

      return Platform.StringUtilities.compare(myLocation.url, otherLocation.url) ||
          myLocation.lineNumber - otherLocation.lineNumber || myLocation.columnNumber - otherLocation.columnNumber;
    }

    const thisMaxWidthExpression = this.maxWidthExpression();
    const otherMaxWidthExpression = other.maxWidthExpression();
    const thisMaxLength = thisMaxWidthExpression ? thisMaxWidthExpression.computedLength() || 0 : 0;
    const otherMaxLength = otherMaxWidthExpression ? otherMaxWidthExpression.computedLength() || 0 : 0;

    const thisMinWidthExpression = this.minWidthExpression();
    const otherMinWidthExpression = other.minWidthExpression();
    const thisMinLength = thisMinWidthExpression ? thisMinWidthExpression.computedLength() || 0 : 0;
    const otherMinLength = otherMinWidthExpression ? otherMinWidthExpression.computedLength() || 0 : 0;

    if (this.section() === Section.MAX) {
      return otherMaxLength - thisMaxLength;
    }
    if (this.section() === Section.MIN) {
      return thisMinLength - otherMinLength;
    }
    return thisMinLength - otherMinLength || otherMaxLength - thisMaxLength;
  }

  section(): Section {
    return this.#section;
  }

  mediaText(): string {
    return this.cssMedia.text || '';
  }

  rawLocation(): SDK.CSSModel.CSSLocation|null {
    if (!this.#rawLocation) {
      this.#rawLocation = this.cssMedia.rawLocation();
    }
    return this.#rawLocation;
  }

  minWidthExpression(): SDK.CSSMedia.CSSMediaQueryExpression|null {
    return this.#minWidthExpression;
  }

  maxWidthExpression(): SDK.CSSMedia.CSSMediaQueryExpression|null {
    return this.#maxWidthExpression;
  }

  minWidthValue(zoomFactor: number): number {
    const minWidthExpression = this.minWidthExpression();
    return minWidthExpression ? (minWidthExpression.computedLength() || 0) / zoomFactor : 0;
  }

  maxWidthValue(zoomFactor: number): number {
    const maxWidthExpression = this.maxWidthExpression();
    return maxWidthExpression ? (maxWidthExpression.computedLength() || 0) / zoomFactor : 0;
  }

  active(): boolean {
    return this.#active;
  }
}