// Copyright 2012 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 type * as Platform from '../../core/platform/platform.js';
import * as SDK from '../../core/sdk/sdk.js';
import type * as Protocol from '../../generated/protocol.js';
import * as TextUtils from '../text_utils/text_utils.js';
import * as Workspace from '../workspace/workspace.js';

import {ContentProviderBasedProject} from './ContentProviderBasedProject.js';
import type {CSSWorkspaceBinding, SourceMapping} from './CSSWorkspaceBinding.js';
import {NetworkProject} from './NetworkProject.js';

export class SASSSourceMapping implements SourceMapping {
  readonly #sourceMapManager: SDK.SourceMapManager.SourceMapManager<SDK.CSSStyleSheetHeader.CSSStyleSheetHeader>;
  readonly #project: ContentProviderBasedProject;
  readonly #eventListeners: Common.EventTarget.EventDescriptor[];
  readonly #bindings: Map<string, Binding>;
  readonly #cssWorkspaceBinding: CSSWorkspaceBinding;

  constructor(
      target: SDK.Target.Target,
      sourceMapManager: SDK.SourceMapManager.SourceMapManager<SDK.CSSStyleSheetHeader.CSSStyleSheetHeader>,
      workspace: Workspace.Workspace.WorkspaceImpl, cssWorkspaceBinding: CSSWorkspaceBinding) {
    this.#sourceMapManager = sourceMapManager;
    this.#cssWorkspaceBinding = cssWorkspaceBinding;
    this.#project = new ContentProviderBasedProject(
        workspace, 'cssSourceMaps:' + target.id(), Workspace.Workspace.projectTypes.Network, '',
        false /* isServiceProject */);
    NetworkProject.setTargetForProject(this.#project, target);

    this.#bindings = new Map();

    this.#eventListeners = [
      this.#sourceMapManager.addEventListener(
          SDK.SourceMapManager.Events.SourceMapAttached, this.sourceMapAttached, this),
      this.#sourceMapManager.addEventListener(
          SDK.SourceMapManager.Events.SourceMapDetached, this.sourceMapDetached, this),
    ];
  }

  private sourceMapAttachedForTest(_sourceMap: SDK.SourceMap.SourceMap|null): void {
  }

  private async sourceMapAttached(
      event: Common.EventTarget
          .EventTargetEvent<{client: SDK.CSSStyleSheetHeader.CSSStyleSheetHeader, sourceMap: SDK.SourceMap.SourceMap}>):
      Promise<void> {
    const header = event.data.client;
    const sourceMap = event.data.sourceMap;
    const project = this.#project;
    const bindings = this.#bindings;
    for (const sourceURL of sourceMap.sourceURLs()) {
      let binding = bindings.get(sourceURL);
      if (!binding) {
        binding = new Binding(project, sourceURL, header.createPageResourceLoadInitiator());
        bindings.set(sourceURL, binding);
      }
      binding.addSourceMap(sourceMap, header.frameId);
    }
    await this.#cssWorkspaceBinding.updateLocations(header);
    this.sourceMapAttachedForTest(sourceMap);
  }

  private async sourceMapDetached(
      event: Common.EventTarget
          .EventTargetEvent<{client: SDK.CSSStyleSheetHeader.CSSStyleSheetHeader, sourceMap: SDK.SourceMap.SourceMap}>):
      Promise<void> {
    const header = event.data.client;
    const sourceMap = event.data.sourceMap;
    const bindings = this.#bindings;
    for (const sourceURL of sourceMap.sourceURLs()) {
      const binding = bindings.get(sourceURL);
      if (binding) {
        binding.removeSourceMap(sourceMap, header.frameId);
        if (!binding.getUiSourceCode()) {
          bindings.delete(sourceURL);
        }
      }
    }
    await this.#cssWorkspaceBinding.updateLocations(header);
  }

  rawLocationToUILocation(rawLocation: SDK.CSSModel.CSSLocation): Workspace.UISourceCode.UILocation|null {
    const header = rawLocation.header();
    if (!header) {
      return null;
    }
    const sourceMap = this.#sourceMapManager.sourceMapForClient(header);
    if (!sourceMap) {
      return null;
    }
    let {lineNumber, columnNumber} = rawLocation;
    // If the source map maps the origin (line:0, column:0) but the CSS header is inline (in a HTML doc),
    // then adjust the line and column numbers.
    if (sourceMap.mapsOrigin() && header.isInline) {
      lineNumber -= header.startLine;
      if (lineNumber === 0) {
        columnNumber -= header.startColumn;
      }
    }
    const entry = sourceMap.findEntry(lineNumber, columnNumber);
    if (!entry?.sourceURL) {
      return null;
    }
    const uiSourceCode = this.#project.uiSourceCodeForURL(entry.sourceURL);
    if (!uiSourceCode) {
      return null;
    }
    return uiSourceCode.uiLocation(entry.sourceLineNumber, entry.sourceColumnNumber);
  }

  uiLocationToRawLocations(uiLocation: Workspace.UISourceCode.UILocation): SDK.CSSModel.CSSLocation[] {
    // TODO(crbug.com/1153123): Revisit the `#columnNumber || 0` and also preserve `undefined` for source maps?
    const {uiSourceCode, lineNumber, columnNumber = 0} = uiLocation;
    const binding = uiSourceCodeToBinding.get(uiSourceCode);
    if (!binding) {
      return [];
    }
    const locations: SDK.CSSModel.CSSLocation[] = [];
    for (const sourceMap of binding.getReferringSourceMaps()) {
      const entries = sourceMap.findReverseEntries(uiSourceCode.url(), lineNumber, columnNumber);
      const header = this.#sourceMapManager.clientForSourceMap(sourceMap);
      if (header) {
        locations.push(
            ...entries.map(entry => new SDK.CSSModel.CSSLocation(header, entry.lineNumber, entry.columnNumber)));
      }
    }
    return locations;
  }

  static uiSourceOrigin(uiSourceCode: Workspace.UISourceCode.UISourceCode): Platform.DevToolsPath.UrlString[] {
    const binding = uiSourceCodeToBinding.get(uiSourceCode);
    if (binding) {
      return binding.getReferringSourceMaps().map(sourceMap => sourceMap.compiledURL());
    }
    return [];
  }

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

const uiSourceCodeToBinding = new WeakMap<Workspace.UISourceCode.UISourceCode, Binding>();

class Binding {
  readonly #project: ContentProviderBasedProject;
  readonly #url: Platform.DevToolsPath.UrlString;
  readonly #initiator: SDK.PageResourceLoader.PageResourceLoadInitiator;
  referringSourceMaps: SDK.SourceMap.SourceMap[];
  uiSourceCode: Workspace.UISourceCode.UISourceCode|null;

  constructor(
      project: ContentProviderBasedProject, url: Platform.DevToolsPath.UrlString,
      initiator: SDK.PageResourceLoader.PageResourceLoadInitiator) {
    this.#project = project;
    this.#url = url;
    this.#initiator = initiator;

    this.referringSourceMaps = [];
    this.uiSourceCode = null;
  }

  private recreateUISourceCodeIfNeeded(frameId: Protocol.Page.FrameId): void {
    const sourceMap = this.referringSourceMaps[this.referringSourceMaps.length - 1];

    const contentType = Common.ResourceType.resourceTypes.SourceMapStyleSheet;
    const embeddedContent = sourceMap.embeddedContentByURL(this.#url);
    const contentProvider = embeddedContent !== null ?
        TextUtils.StaticContentProvider.StaticContentProvider.fromString(this.#url, contentType, embeddedContent) :
        new SDK.CompilerSourceMappingContentProvider.CompilerSourceMappingContentProvider(
            this.#url, contentType, this.#initiator);
    const newUISourceCode = this.#project.createUISourceCode(this.#url, contentType);
    uiSourceCodeToBinding.set(newUISourceCode, this);
    const mimeType = Common.ResourceType.ResourceType.mimeFromURL(this.#url) || contentType.canonicalMimeType();
    const metadata = typeof embeddedContent === 'string' ?
        new Workspace.UISourceCode.UISourceCodeMetadata(null, embeddedContent.length) :
        null;

    if (this.uiSourceCode) {
      NetworkProject.cloneInitialFrameAttribution(this.uiSourceCode, newUISourceCode);
      this.#project.removeUISourceCode(this.uiSourceCode.url());
    } else {
      NetworkProject.setInitialFrameAttribution(newUISourceCode, frameId);
    }
    this.uiSourceCode = newUISourceCode;
    this.#project.addUISourceCodeWithProvider(this.uiSourceCode, contentProvider, metadata, mimeType);
  }

  addSourceMap(sourceMap: SDK.SourceMap.SourceMap, frameId: Protocol.Page.FrameId): void {
    if (this.uiSourceCode) {
      NetworkProject.addFrameAttribution(this.uiSourceCode, frameId);
    }
    this.referringSourceMaps.push(sourceMap);
    this.recreateUISourceCodeIfNeeded(frameId);
  }

  removeSourceMap(sourceMap: SDK.SourceMap.SourceMap, frameId: Protocol.Page.FrameId): void {
    const uiSourceCode = (this.uiSourceCode as Workspace.UISourceCode.UISourceCode);
    NetworkProject.removeFrameAttribution(uiSourceCode, frameId);
    const lastIndex = this.referringSourceMaps.lastIndexOf(sourceMap);
    if (lastIndex !== -1) {
      this.referringSourceMaps.splice(lastIndex, 1);
    }
    if (!this.referringSourceMaps.length) {
      this.#project.removeUISourceCode(uiSourceCode.url());
      this.uiSourceCode = null;
    } else {
      this.recreateUISourceCodeIfNeeded(frameId);
    }
  }

  getReferringSourceMaps(): SDK.SourceMap.SourceMap[] {
    return this.referringSourceMaps;
  }

  getUiSourceCode(): Workspace.UISourceCode.UISourceCode|null {
    return this.uiSourceCode;
  }
}