// 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 Platform from '../../core/platform/platform.js';
import * as Root from '../../core/root/root.js';
import * as SDK from '../../core/sdk/sdk.js';
import type * as Workspace from '../workspace/workspace.js';

import {
  type LiveLocation as LiveLocationInterface,
  type LiveLocationPool,
  LiveLocationWithPool,
} from './LiveLocation.js';
import type {ResourceMapping} from './ResourceMapping.js';
import {SASSSourceMapping} from './SASSSourceMapping.js';
import {StylesSourceMapping} from './StylesSourceMapping.js';

export class CSSWorkspaceBinding implements SDK.TargetManager.SDKModelObserver<SDK.CSSModel.CSSModel> {
  readonly #resourceMapping: ResourceMapping;
  readonly #modelToInfo: Map<SDK.CSSModel.CSSModel, ModelInfo>;
  readonly #liveLocationPromises: Set<Promise<unknown>>;

  constructor(resourceMapping: ResourceMapping, targetManager: SDK.TargetManager.TargetManager) {
    this.#resourceMapping = resourceMapping;
    this.#resourceMapping.cssWorkspaceBinding = this;
    this.#modelToInfo = new Map();
    targetManager.observeModels(SDK.CSSModel.CSSModel, this);

    this.#liveLocationPromises = new Set();
  }

  static instance(opts: {
    forceNew: boolean|null,
    resourceMapping: ResourceMapping|null,
    targetManager: SDK.TargetManager.TargetManager|null,
  } = {forceNew: null, resourceMapping: null, targetManager: null}): CSSWorkspaceBinding {
    const {forceNew, resourceMapping, targetManager} = opts;
    if (forceNew) {
      if (!resourceMapping || !targetManager) {
        throw new Error(`Unable to create CSSWorkspaceBinding: resourceMapping and targetManager must be provided: ${
            new Error().stack}`);
      }

      Root.DevToolsContext.globalInstance().set(
          CSSWorkspaceBinding, new CSSWorkspaceBinding(resourceMapping, targetManager));
    }

    return Root.DevToolsContext.globalInstance().get(CSSWorkspaceBinding);
  }

  static removeInstance(): void {
    Root.DevToolsContext.globalInstance().delete(CSSWorkspaceBinding);
  }

  get modelToInfo(): Map<SDK.CSSModel.CSSModel, ModelInfo> {
    return this.#modelToInfo;
  }

  private getCSSModelInfo(cssModel: SDK.CSSModel.CSSModel): ModelInfo {
    return this.#modelToInfo.get(cssModel) as ModelInfo;
  }

  modelAdded(cssModel: SDK.CSSModel.CSSModel): void {
    this.#modelToInfo.set(cssModel, new ModelInfo(cssModel, this.#resourceMapping, this));
  }

  modelRemoved(cssModel: SDK.CSSModel.CSSModel): void {
    this.getCSSModelInfo(cssModel).dispose();
    this.#modelToInfo.delete(cssModel);
  }

  /**
   * The promise returned by this function is resolved once all *currently*
   * pending LiveLocations are processed.
   */
  async pendingLiveLocationChangesPromise(): Promise<void> {
    await Promise.all(this.#liveLocationPromises);
  }

  private recordLiveLocationChange(promise: Promise<unknown>): void {
    void promise.then(() => {
      this.#liveLocationPromises.delete(promise);
    });
    this.#liveLocationPromises.add(promise);
  }

  async updateLocations(header: SDK.CSSStyleSheetHeader.CSSStyleSheetHeader): Promise<void> {
    const updatePromise = this.getCSSModelInfo(header.cssModel()).updateLocations(header);
    this.recordLiveLocationChange(updatePromise);
    await updatePromise;
  }

  createLiveLocation(
      rawLocation: SDK.CSSModel.CSSLocation, updateDelegate: (arg0: LiveLocationInterface) => Promise<void>,
      locationPool: LiveLocationPool): Promise<LiveLocation> {
    const locationPromise =
        this.getCSSModelInfo(rawLocation.cssModel()).createLiveLocation(rawLocation, updateDelegate, locationPool);
    this.recordLiveLocationChange(locationPromise);
    return locationPromise;
  }

  propertyRawLocation(cssProperty: SDK.CSSProperty.CSSProperty, forName: boolean): SDK.CSSModel.CSSLocation|null {
    const style = cssProperty.ownerStyle;
    if (!style || style.type !== SDK.CSSStyleDeclaration.Type.Regular || !style.styleSheetId) {
      return null;
    }
    const header = style.cssModel().styleSheetHeaderForId(style.styleSheetId);
    if (!header) {
      return null;
    }

    const range = forName ? cssProperty.nameRange() : cssProperty.valueRange();
    if (!range) {
      return null;
    }

    const lineNumber = range.startLine;
    const columnNumber = range.startColumn;
    return new SDK.CSSModel.CSSLocation(
        header, header.lineNumberInSource(lineNumber), header.columnNumberInSource(lineNumber, columnNumber));
  }

  propertyUILocation(cssProperty: SDK.CSSProperty.CSSProperty, forName: boolean): Workspace.UISourceCode.UILocation
      |null {
    const rawLocation = this.propertyRawLocation(cssProperty, forName);
    if (!rawLocation) {
      return null;
    }
    return this.rawLocationToUILocation(rawLocation);
  }

  rawLocationToUILocation(rawLocation: SDK.CSSModel.CSSLocation): Workspace.UISourceCode.UILocation|null {
    return this.getCSSModelInfo(rawLocation.cssModel()).rawLocationToUILocation(rawLocation);
  }

  uiLocationToRawLocations(uiLocation: Workspace.UISourceCode.UILocation): SDK.CSSModel.CSSLocation[] {
    const rawLocations = [];
    for (const modelInfo of this.#modelToInfo.values()) {
      rawLocations.push(...modelInfo.uiLocationToRawLocations(uiLocation));
    }
    return rawLocations;
  }
}

export interface SourceMapping {
  rawLocationToUILocation(rawLocation: SDK.CSSModel.CSSLocation): Workspace.UISourceCode.UILocation|null;

  uiLocationToRawLocations(uiLocation: Workspace.UISourceCode.UILocation): SDK.CSSModel.CSSLocation[];
}

export class ModelInfo {
  readonly #eventListeners: Common.EventTarget.EventDescriptor[];
  readonly #resourceMapping: ResourceMapping;
  #stylesSourceMapping: StylesSourceMapping;
  #sassSourceMapping: SASSSourceMapping;
  readonly #locations: Platform.MapUtilities.Multimap<SDK.CSSStyleSheetHeader.CSSStyleSheetHeader, LiveLocation>;
  readonly #unboundLocations: Platform.MapUtilities.Multimap<Platform.DevToolsPath.UrlString, LiveLocation>;
  constructor(
      cssModel: SDK.CSSModel.CSSModel, resourceMapping: ResourceMapping, cssWorkspaceBinding: CSSWorkspaceBinding) {
    this.#eventListeners = [
      cssModel.addEventListener(
          SDK.CSSModel.Events.StyleSheetAdded,
          event => {
            void this.styleSheetAdded(event);
          },
          this),
      cssModel.addEventListener(
          SDK.CSSModel.Events.StyleSheetRemoved,
          event => {
            void this.styleSheetRemoved(event);
          },
          this),
    ];

    this.#resourceMapping = resourceMapping;
    this.#stylesSourceMapping = new StylesSourceMapping(cssModel, resourceMapping.workspace);
    const sourceMapManager = cssModel.sourceMapManager();
    this.#sassSourceMapping =
        new SASSSourceMapping(cssModel.target(), sourceMapManager, resourceMapping.workspace, cssWorkspaceBinding);

    this.#locations = new Platform.MapUtilities.Multimap();
    this.#unboundLocations = new Platform.MapUtilities.Multimap();
  }

  get locations(): Platform.MapUtilities.Multimap<SDK.CSSStyleSheetHeader.CSSStyleSheetHeader, LiveLocation> {
    return this.#locations;
  }

  async createLiveLocation(
      rawLocation: SDK.CSSModel.CSSLocation, updateDelegate: (arg0: LiveLocationInterface) => Promise<void>,
      locationPool: LiveLocationPool): Promise<LiveLocation> {
    const location = new LiveLocation(rawLocation, this, updateDelegate, locationPool);
    const header = rawLocation.header();
    if (header) {
      location.setHeader(header);
      this.#locations.set(header, location);
      await location.update();
    } else {
      this.#unboundLocations.set(rawLocation.url, location);
    }
    return location;
  }

  disposeLocation(location: LiveLocation): void {
    const header = location.header();
    if (header) {
      this.#locations.delete(header, location);
    } else {
      this.#unboundLocations.delete(location.url, location);
    }
  }

  updateLocations(header: SDK.CSSStyleSheetHeader.CSSStyleSheetHeader): Promise<void[]> {
    const promises = [];
    for (const location of this.#locations.get(header)) {
      promises.push(location.update());
    }
    return Promise.all(promises);
  }

  private async styleSheetAdded(
      event: Common.EventTarget.EventTargetEvent<SDK.CSSStyleSheetHeader.CSSStyleSheetHeader>): Promise<void> {
    const header = event.data;
    if (!header.sourceURL) {
      return;
    }

    const promises = [];
    for (const location of this.#unboundLocations.get(header.sourceURL)) {
      location.setHeader(header);
      this.#locations.set(header, location);
      promises.push(location.update());
    }
    await Promise.all(promises);
    this.#unboundLocations.deleteAll(header.sourceURL);
  }

  private async styleSheetRemoved(
      event: Common.EventTarget.EventTargetEvent<SDK.CSSStyleSheetHeader.CSSStyleSheetHeader>): Promise<void> {
    const header = event.data;
    const promises = [];
    for (const location of this.#locations.get(header)) {
      location.setHeader(header);
      this.#unboundLocations.set(location.url, location);
      promises.push(location.update());
    }
    await Promise.all(promises);
    this.#locations.deleteAll(header);
  }

  addSourceMap(sourceUrl: Platform.DevToolsPath.UrlString, sourceMapUrl: Platform.DevToolsPath.UrlString): void {
    this.#stylesSourceMapping.addSourceMap(sourceUrl, sourceMapUrl);
  }

  rawLocationToUILocation(rawLocation: SDK.CSSModel.CSSLocation): Workspace.UISourceCode.UILocation|null {
    let uiLocation: (Workspace.UISourceCode.UILocation|null)|null = null;
    uiLocation = uiLocation || this.#sassSourceMapping.rawLocationToUILocation(rawLocation);
    uiLocation = uiLocation || this.#stylesSourceMapping.rawLocationToUILocation(rawLocation);
    uiLocation = uiLocation || this.#resourceMapping.cssLocationToUILocation(rawLocation);
    return uiLocation;
  }

  uiLocationToRawLocations(uiLocation: Workspace.UISourceCode.UILocation): SDK.CSSModel.CSSLocation[] {
    let rawLocations = this.#sassSourceMapping.uiLocationToRawLocations(uiLocation);
    if (rawLocations.length) {
      return rawLocations;
    }
    rawLocations = this.#stylesSourceMapping.uiLocationToRawLocations(uiLocation);
    if (rawLocations.length) {
      return rawLocations;
    }
    return this.#resourceMapping.uiLocationToCSSLocations(uiLocation);
  }

  dispose(): void {
    Common.EventTarget.removeEventListeners(this.#eventListeners);
    this.#stylesSourceMapping.dispose();
    this.#sassSourceMapping.dispose();
  }
}

export class LiveLocation extends LiveLocationWithPool {
  readonly url: Platform.DevToolsPath.UrlString;
  readonly #lineNumber: number;
  readonly #columnNumber: number;
  readonly #info: ModelInfo;
  #header: SDK.CSSStyleSheetHeader.CSSStyleSheetHeader|null;
  constructor(
      rawLocation: SDK.CSSModel.CSSLocation, info: ModelInfo,
      updateDelegate: (arg0: LiveLocationInterface) => Promise<void>, locationPool: LiveLocationPool) {
    super(updateDelegate, locationPool);
    this.url = rawLocation.url;
    this.#lineNumber = rawLocation.lineNumber;
    this.#columnNumber = rawLocation.columnNumber;
    this.#info = info;
    this.#header = null;
  }

  header(): SDK.CSSStyleSheetHeader.CSSStyleSheetHeader|null {
    return this.#header;
  }

  setHeader(header: SDK.CSSStyleSheetHeader.CSSStyleSheetHeader|null): void {
    this.#header = header;
  }

  override async uiLocation(): Promise<Workspace.UISourceCode.UILocation|null> {
    if (!this.#header) {
      return null;
    }
    const rawLocation = new SDK.CSSModel.CSSLocation(this.#header, this.#lineNumber, this.#columnNumber);
    return CSSWorkspaceBinding.instance().rawLocationToUILocation(rawLocation);
  }

  override dispose(): void {
    super.dispose();
    this.#info.disposeLocation(this);
  }
}