bbscript.js

import { debounce } from "@ember/runloop";
import loadscript from "discourse/lib/load-script";
import { withPluginApi } from "discourse/lib/plugin-api";
/* global bbscriptParser */

/**
 * @type {Array<{callback: function, on: string}>}
 */
let attachedPreviewBBScripts = [];
/** @type {WeakMap<Element, CallableFunction[]>} */
const initBBScripts = new WeakMap();

const PARENT_PREVIEW_WRAPPER_CLASS = "d-editor-preview";

const documentObserver = new IntersectionObserver(
  (entries, observer) => {
    entries.forEach((entry) => {
      if (entry.isIntersecting) {
        const post = entry.target;
        const callback = initBBScripts.get(post);
        callback?.forEach((c) => c());
        initBBScripts.delete(post);
        observer.unobserve(post);
      }
    });
  },
  {
    threshold: 0,
    rootMargin: "10px 0px 0px 0px",
  }
);

/**
 * Check if the post is a preview. If it is a preview, debounce the function
 * @param {HTMLElement} post
 */
function checkIsPreview(post) {
  let isPreview = post.classList.contains(PARENT_PREVIEW_WRAPPER_CLASS);
  if (isPreview) {
    // prevent multiple calls to addBBScriptLogic
    // preview mode is constantly updating based on user input
    debounce(this, addBBScriptLogic, post, true, 1000);
  } else {
    addBBScriptLogic(post, false);
  }
}

/**
 * Adds the bbscript functions to the post
 * @param {HTMLElement} post the post itself
 */
function addBBScriptLogic(post, isPreview = false) {
  if (isPreview) {
    attachedPreviewBBScripts.forEach(({ callback, on }) => {
      post.removeEventListener(on, callback, true);
    });
    attachedPreviewBBScripts = [];
    delete bbscriptParser.bbscriptData.preview;
  }

  post.querySelectorAll("template[data-bbcode-plus='script']").forEach((el) => {
    const callerId = el.getAttribute("data-bbscript-id") || "";
    const callerClass = el.getAttribute("data-bbscript-class") || "";
    /** @type {string} */
    const content = el.content.textContent || "";
    let version = el.getAttribute("data-bbscript-ver") || "";
    const on = el.getAttribute("data-bbscript-on") || "init"; // valid on events: init, click, mouseover, mouseout, etc.
    let astTree;
    if (version === "") {
      // unknown version. check for unique () style of bbscript2
      version = content.split("\n").some((line) => line.trim().startsWith("(")) ? "2" : "1";
    }
    if (version === "2") {
      const parsed = bbscriptParser.bbscript2Parser.parse(content);
      astTree = parsed.ast;
      if (parsed.formattedErrors.length) {
        // eslint-disable-next-line no-console
        console.warn(parsed.formattedErrors);
      }
    } else {
      astTree = bbscriptParser.bbscriptProcessorV1.parse(content);
    }
    if (on === "init") {
      let target;
      if (callerClass) {
        target = document.querySelectorAll("." + callerClass + "__" + callerId) || undefined;
      }
      // only fire when the post is visible
      if (!initBBScripts.has(post)) {
        initBBScripts.set(post, []);
      }
      initBBScripts.get(post).push(() => {
        triggerBBScript(callerId, callerClass, astTree, version, target);
      });
      documentObserver.observe(post);
    } else {
      const callback = (ev) => {
        const target = ev.target?.closest("." + callerClass + "__" + callerId);
        if (target) {
          triggerBBScript(callerId, callerClass, astTree, version, target);
        }
      };
      // event delegation
      post.addEventListener(on, callback, true);
      if (isPreview) {
        attachedPreviewBBScripts.push({ callback, on });
      }
    }
  });
}

/**
 * @param {string} callerId
 * @param {string} callerClass
 * @param {ASTNode[] | astNode[]} astTree
 * @param {string} version
 * @param {Element | NodeListOf<Element>} [target]
 * @returns {void}
 */
const triggerBBScript = (callerId, callerClass, astTree, version, target) => {
  if (version === "1") {
    bbscriptParser.bbscriptProcessorV1.execAll(astTree, callerId, callerClass, { target });
  } else if (version === "2") {
    try {
      bbscriptParser.bbscriptProcessorV2.execAll(astTree, callerId, callerClass, { target });
    } catch (e) {
      if (e?.message !== "BBScript Stop Command") {
        // eslint-disable-next-line no-console
        console.warn(e);
      }
    }
  }
};

function initializeBBScript(api) {
  const siteSettings = api.container.lookup("service:site-settings");
  if (!siteSettings.enable_bbscript) {
    return;
  }

  api.decorateCookedElement(
    (post) => {
      loadscript("/plugins/bbcode/javascripts/bbscript-parser.min.js").then(() => {
        checkIsPreview(post);
      });
    },
    {
      id: "add bbscript",
      afterAdopt: true,
    }
  );
}

export default {
  name: "bbscript",
  initialize() {
    withPluginApi("0.11.1", initializeBBScript);
  },
};