// 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 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 Buttons from '../../../../ui/components/buttons/buttons.js';
import * as LegacyComponents from '../../../../ui/legacy/components/utils/utils.js';
import * as UI from '../../../../ui/legacy/legacy.js';
import * as Lit from '../../../../ui/lit/lit.js';
import * as PanelsCommon from '../../../common/common.js';

const {html} = Lit;
const {widget} = UI.Widget;

interface ViewInput {
  relatedNodeEl: Lit.LitTemplate|undefined;
  fallbackUrl?: Platform.DevToolsPath.UrlString;
  fallbackHtmlSnippet?: string;
  fallbackText?: string;
}

type View = (input: ViewInput, output: undefined, target: HTMLElement) => void;

export const DEFAULT_VIEW: View = (input, output, target) => {
  const {
    relatedNodeEl,
    fallbackUrl,
    fallbackHtmlSnippet,
    fallbackText,
  } = input;

  let template;
  if (relatedNodeEl) {
    template = html`<div class='node-link'>${relatedNodeEl}</div>`;
  } else if (fallbackUrl) {
    const MAX_URL_LENGTH = 20;
    const options = {
      tabStop: true,
      showColumnNumber: false,
      inlineFrameIndex: 0,
      maxLength: MAX_URL_LENGTH,
    };
    const linkEl = LegacyComponents.Linkifier.Linkifier.linkifyURL(fallbackUrl, options);
    template = html`<div class='node-link'>
      <style>${Buttons.textButtonStyles}</style>
      ${linkEl}
    </div>`;
  } else if (fallbackHtmlSnippet) {
    // TODO: Use CodeHighlighter.
    template = html`<pre style='text-wrap: auto'>${fallbackHtmlSnippet}</pre>`;
  } else if (fallbackText) {
    template = html`<span>${fallbackText}</span>`;
  } else {
    template = Lit.nothing;
  }

  Lit.render(template, target);
};

export interface NodeLinkData {
  backendNodeId: Protocol.DOM.BackendNodeId;
  frame?: string;
  options?: PanelsCommon.DOMLinkifier.Options;
  /**
   * URL to display if backendNodeId cannot be resolved (ie for traces loaded from disk).
   * Will be given to linkifyURL. Use this or one of the other fallback fields.
   */
  fallbackUrl?: Platform.DevToolsPath.UrlString;
  /**
   * Text to display if backendNodeId cannot be resolved (ie for traces loaded from disk).
   * Displayed as monospace code.
   */
  fallbackHtmlSnippet?: string;
  /**
   * Text to display if backendNodeId cannot be resolved (ie for traces loaded from disk).
   * Displayed as plain text.
   */
  fallbackText?: string;
}

export class NodeLink extends UI.Widget.Widget {
  #view: View;
  #backendNodeId?: Protocol.DOM.BackendNodeId;
  #frame?: string;
  #options?: PanelsCommon.DOMLinkifier.Options;
  #fallbackUrl?: Platform.DevToolsPath.UrlString;
  #fallbackHtmlSnippet?: string;
  #fallbackText?: string;
  /**
   * Track the linkified Node for a given backend NodeID to avoid repeated lookups on re-render.
   * Also tracks if we fail to resolve a node, to ensure we don't try on each subsequent re-render.
   */
  #linkifiedNodeForBackendId = new Map<Protocol.DOM.BackendNodeId, Lit.LitTemplate|'NO_NODE_FOUND'>();

  constructor(element?: HTMLElement, view: View = DEFAULT_VIEW) {
    super(element, {useShadowDom: true});
    this.#view = view;
  }

  set data(data: NodeLinkData) {
    this.#backendNodeId = data.backendNodeId;
    this.#frame = data.frame;
    this.#options = data.options;
    this.#fallbackUrl = data.fallbackUrl;
    this.#fallbackHtmlSnippet = data.fallbackHtmlSnippet;
    this.#fallbackText = data.fallbackText;
    this.requestUpdate();
  }

  async #linkify(): Promise<Lit.LitTemplate|undefined> {
    if (this.#backendNodeId === undefined) {
      return;
    }
    const fromCache = this.#linkifiedNodeForBackendId.get(this.#backendNodeId);
    if (fromCache) {
      if (fromCache === 'NO_NODE_FOUND') {
        return undefined;
      }
      return fromCache;
    }

    const target = SDK.TargetManager.TargetManager.instance().primaryPageTarget();
    const domModel = target?.model(SDK.DOMModel.DOMModel);
    if (!domModel) {
      return undefined;
    }
    const domNodesMap = await domModel.pushNodesByBackendIdsToFrontend(new Set([this.#backendNodeId]));
    const node = domNodesMap?.get(this.#backendNodeId);
    if (!node) {
      this.#linkifiedNodeForBackendId.set(this.#backendNodeId, 'NO_NODE_FOUND');
      return;
    }

    if (node.frameId() !== this.#frame) {
      this.#linkifiedNodeForBackendId.set(this.#backendNodeId, 'NO_NODE_FOUND');
      return;
    }

    // TODO: it'd be nice if we could specify what attributes to render,
    // ex for the Viewport insight: <meta content="..."> (instead of just <meta>)
    const linkedNode = PanelsCommon.DOMLinkifier.Linkifier.instance().linkify(node, this.#options);
    this.#linkifiedNodeForBackendId.set(this.#backendNodeId, linkedNode);
    return linkedNode;
  }

  override async performUpdate(): Promise<void> {
    const input: ViewInput = {
      relatedNodeEl: await this.#linkify(),
      fallbackUrl: this.#fallbackUrl,
      fallbackHtmlSnippet: this.#fallbackHtmlSnippet,
      fallbackText: this.#fallbackText,
    };
    this.#view(input, undefined, this.contentElement);
  }
}

export function nodeLink(data: NodeLinkData): Lit.TemplateResult {
  return html`${widget(NodeLink, {data})}`;
}