discourse/app/assets/javascripts/pretty-text/addon/emoji.js

import {
  aliases,
  emojis,
  replacements,
  searchAliases,
  tonableEmojis,
  translations,
} from "pretty-text/emoji/data";
import { IMAGE_VERSION } from "pretty-text/emoji/version";

const extendedEmoji = {};

export function registerEmoji(code, url, group) {
  code = code.toLowerCase();
  extendedEmoji[code] = { url, group };
}

export function extendedEmojiList() {
  return extendedEmoji;
}

const emojiHash = {};

// https://github.com/mathiasbynens/emoji-regex/blob/main/text.js
export const emojiReplacementRegex =
  "\uD83C\uDFF4\uDB40\uDC67\uDB40\uDC62(?:\uDB40\uDC77\uDB40\uDC6C\uDB40\uDC73|\uDB40\uDC73\uDB40\uDC63\uDB40\uDC74|\uDB40\uDC65\uDB40\uDC6E\uDB40\uDC67)\uDB40\uDC7F|(?:\uD83E\uDDD1\uD83C\uDFFF\u200D\u2764\uFE0F\u200D(?:\uD83D\uDC8B\u200D)?\uD83E\uDDD1|\uD83D\uDC69\uD83C\uDFFF\u200D\uD83E\uDD1D\u200D(?:\uD83D[\uDC68\uDC69]))(?:\uD83C[\uDFFB-\uDFFE])|(?:\uD83E\uDDD1\uD83C\uDFFE\u200D\u2764\uFE0F\u200D(?:\uD83D\uDC8B\u200D)?\uD83E\uDDD1|\uD83D\uDC69\uD83C\uDFFE\u200D\uD83E\uDD1D\u200D(?:\uD83D[\uDC68\uDC69]))(?:\uD83C[\uDFFB-\uDFFD\uDFFF])|(?:\uD83E\uDDD1\uD83C\uDFFD\u200D\u2764\uFE0F\u200D(?:\uD83D\uDC8B\u200D)?\uD83E\uDDD1|\uD83D\uDC69\uD83C\uDFFD\u200D\uD83E\uDD1D\u200D(?:\uD83D[\uDC68\uDC69]))(?:\uD83C[\uDFFB\uDFFC\uDFFE\uDFFF])|(?:\uD83E\uDDD1\uD83C\uDFFC\u200D\u2764\uFE0F\u200D(?:\uD83D\uDC8B\u200D)?\uD83E\uDDD1|\uD83D\uDC69\uD83C\uDFFC\u200D\uD83E\uDD1D\u200D(?:\uD83D[\uDC68\uDC69]))(?:\uD83C[\uDFFB\uDFFD-\uDFFF])|(?:\uD83E\uDDD1\uD83C\uDFFB\u200D\u2764\uFE0F\u200D(?:\uD83D\uDC8B\u200D)?\uD83E\uDDD1|\uD83D\uDC69\uD83C\uDFFB\u200D\uD83E\uDD1D\u200D(?:\uD83D[\uDC68\uDC69]))(?:\uD83C[\uDFFC-\uDFFF])|\uD83D\uDC68(?:\uD83C\uDFFB(?:\u200D(?:\u2764\uFE0F\u200D(?:\uD83D\uDC8B\u200D\uD83D\uDC68(?:\uD83C[\uDFFB-\uDFFF])|\uD83D\uDC68(?:\uD83C[\uDFFB-\uDFFF]))|\uD83E\uDD1D\u200D\uD83D\uDC68(?:\uD83C[\uDFFC-\uDFFF])|[\u2695\u2696\u2708]\uFE0F|\uD83C[\uDF3E\uDF73\uDF7C\uDF93\uDFA4\uDFA8\uDFEB\uDFED]|\uD83D[\uDCBB\uDCBC\uDD27\uDD2C\uDE80\uDE92]|\uD83E[\uDDAF-\uDDB3\uDDBC\uDDBD]))?|(?:\uD83C[\uDFFC-\uDFFF])\u200D\u2764\uFE0F\u200D(?:\uD83D\uDC8B\u200D\uD83D\uDC68(?:\uD83C[\uDFFB-\uDFFF])|\uD83D\uDC68(?:\uD83C[\uDFFB-\uDFFF]))|\u200D(?:\u2764\uFE0F\u200D(?:\uD83D\uDC8B\u200D)?\uD83D\uDC68|(?:\uD83D[\uDC68\uDC69])\u200D(?:\uD83D\uDC66\u200D\uD83D\uDC66|\uD83D\uDC67\u200D(?:\uD83D[\uDC66\uDC67]))|\uD83D\uDC66\u200D\uD83D\uDC66|\uD83D\uDC67\u200D(?:\uD83D[\uDC66\uDC67])|\uD83C[\uDF3E\uDF73\uDF7C\uDF93\uDFA4\uDFA8\uDFEB\uDFED]|\uD83D[\uDCBB\uDCBC\uDD27\uDD2C\uDE80\uDE92]|\uD83E[\uDDAF-\uDDB3\uDDBC\uDDBD])|\uD83C\uDFFF\u200D(?:\uD83E\uDD1D\u200D\uD83D\uDC68(?:\uD83C[\uDFFB-\uDFFE])|\uD83C[\uDF3E\uDF73\uDF7C\uDF93\uDFA4\uDFA8\uDFEB\uDFED]|\uD83D[\uDCBB\uDCBC\uDD27\uDD2C\uDE80\uDE92]|\uD83E[\uDDAF-\uDDB3\uDDBC\uDDBD])|\uD83C\uDFFE\u200D(?:\uD83E\uDD1D\u200D\uD83D\uDC68(?:\uD83C[\uDFFB-\uDFFD\uDFFF])|\uD83C[\uDF3E\uDF73\uDF7C\uDF93\uDFA4\uDFA8\uDFEB\uDFED]|\uD83D[\uDCBB\uDCBC\uDD27\uDD2C\uDE80\uDE92]|\uD83E[\uDDAF-\uDDB3\uDDBC\uDDBD])|\uD83C\uDFFD\u200D(?:\uD83E\uDD1D\u200D\uD83D\uDC68(?:\uD83C[\uDFFB\uDFFC\uDFFE\uDFFF])|\uD83C[\uDF3E\uDF73\uDF7C\uDF93\uDFA4\uDFA8\uDFEB\uDFED]|\uD83D[\uDCBB\uDCBC\uDD27\uDD2C\uDE80\uDE92]|\uD83E[\uDDAF-\uDDB3\uDDBC\uDDBD])|\uD83C\uDFFC\u200D(?:\uD83E\uDD1D\u200D\uD83D\uDC68(?:\uD83C[\uDFFB\uDFFD-\uDFFF])|\uD83C[\uDF3E\uDF73\uDF7C\uDF93\uDFA4\uDFA8\uDFEB\uDFED]|\uD83D[\uDCBB\uDCBC\uDD27\uDD2C\uDE80\uDE92]|\uD83E[\uDDAF-\uDDB3\uDDBC\uDDBD])|(?:\uD83C\uDFFF\u200D[\u2695\u2696\u2708]|\uD83C\uDFFE\u200D[\u2695\u2696\u2708]|\uD83C\uDFFD\u200D[\u2695\u2696\u2708]|\uD83C\uDFFC\u200D[\u2695\u2696\u2708]|\u200D[\u2695\u2696\u2708])\uFE0F|\u200D(?:(?:\uD83D[\uDC68\uDC69])\u200D(?:\uD83D[\uDC66\uDC67])|\uD83D[\uDC66\uDC67])|\uD83C\uDFFF|\uD83C\uDFFE|\uD83C\uDFFD|\uD83C\uDFFC)?|(?:\uD83D\uDC69(?:\uD83C\uDFFB\u200D\u2764\uFE0F\u200D(?:\uD83D\uDC8B\u200D(?:\uD83D[\uDC68\uDC69])|\uD83D[\uDC68\uDC69])|(?:\uD83C[\uDFFC-\uDFFF])\u200D\u2764\uFE0F\u200D(?:\uD83D\uDC8B\u200D(?:\uD83D[\uDC68\uDC69])|\uD83D[\uDC68\uDC69]))|\uD83E\uDDD1(?:\uD83C[\uDFFB-\uDFFF])\u200D\uD83E\uDD1D\u200D\uD83E\uDDD1)(?:\uD83C[\uDFFB-\uDFFF])|\uD83D\uDC69\u200D\uD83D\uDC69\u200D(?:\uD83D\uDC66\u200D\uD83D\uDC66|\uD83D\uDC67\u200D(?:\uD83D[\uDC66\uDC67]))|\uD83D\uDC69(?:\u200D(?:\u2764\uFE0F\u200D(?:\uD83D\uDC8B\u200D(?:\uD83D[\uDC68\uDC69])|\uD83D[\uDC68\uDC69])|\uD83C[\uDF3E\uDF73\uDF7C\uDF93\uDFA4\uDFA8\uDFEB\uDFED]|\uD83D[\uDCBB\uDCBC\uDD27\uDD2C\uDE80\uDE92]|\uD83E[\uDDAF-\uDDB3\uDDBC\uDDBD])|\uD83C\uDFFF\u200D(?:\uD83C[\uDF3E\uDF73\uDF7C\uDF93\uDFA4\uDFA8\uDFEB\uDFED]|\uD83D[\uDCBB\uDCBC\uDD27\uDD2C\uDE80\uDE92]|\uD83E[\uDDAF-\uDDB3\uDDBC\uDDBD])

function textEmojiRegex(inlineEmoji) {
  return inlineEmoji ? /:[^\s:]+(?::t\d)?:?/g : /\B:[^\s:]+(?::t\d)?:?\B/g;
}

// add all default emojis
emojis.forEach((code) => (emojiHash[code] = true));

// and their aliases
const aliasHash = {};
Object.keys(aliases).forEach((name) => {
  aliases[name].forEach((alias) => (aliasHash[alias] = name));
});

function isReplacableInlineEmoji(string, index, inlineEmoji) {
  if (inlineEmoji) {
    return true;
  }

  // index depends on regex; when `inlineEmoji` is false, the regex starts
  // with a `\B` character, so there's no need to subtract from the index
  const beforeEmoji = string.slice(0, index);

  return (
    beforeEmoji.length === 0 ||
    /(?:\s|[>.,\/#!$%^&*;:{}=\-_`~()])$/.test(beforeEmoji) ||
    new RegExp(`(?:${emojiReplacementRegex})$`, "g").test(beforeEmoji)
  );
}

export function performEmojiUnescape(string, opts) {
  if (!string) {
    return;
  }

  const allTranslations = Object.assign(
    {},
    translations,
    opts.customEmojiTranslation || {}
  );

  const replacementFunction = (m, index) => {
    const isEmoticon = opts.enableEmojiShortcuts && !!allTranslations[m];
    const isUnicodeEmoticon = !!replacements[m];
    let emojiVal;

    if (isEmoticon) {
      emojiVal = allTranslations[m];
    } else if (isUnicodeEmoticon) {
      emojiVal = replacements[m];
    } else {
      emojiVal = m.slice(1, m.length - 1);
    }
    const hasEndingColon = m.lastIndexOf(":") === m.length - 1;
    const url = buildEmojiUrl(emojiVal, opts);
    let classes = isCustomEmoji(emojiVal, opts)
      ? "emoji emoji-custom"
      : "emoji";

    if (opts.class) {
      classes = `${classes} ${opts.class}`;
    }

    const isReplacable =
      (isEmoticon || hasEndingColon || isUnicodeEmoticon) &&
      isReplacableInlineEmoji(string, index, opts.inlineEmoji);

    return url && isReplacable
      ? `<img width="20" height="20" src='${url}' ${
          opts.skipTitle ? "" : `title='${emojiVal}'`
        } ${
          opts.lazy ? "loading='lazy' " : ""
        }alt='${emojiVal}' class='${classes}'>`
      : m;
  };

  return string
    .replace(new RegExp(emojiReplacementRegex, "g"), replacementFunction)
    .replace(textEmojiRegex(opts.inlineEmoji), replacementFunction);
}

export function performEmojiEscape(string, opts) {
  const allTranslations = Object.assign(
    {},
    translations,
    opts.customEmojiTranslation || {}
  );

  const replacementFunction = (m, index) => {
    if (isReplacableInlineEmoji(string, index, opts.inlineEmoji)) {
      if (!!allTranslations[m]) {
        return opts.emojiShortcuts ? `:${allTranslations[m]}:` : m;
      } else if (!!replacements[m]) {
        return `:${replacements[m]}:`;
      }
    }

    return m;
  };

  return string
    .replace(new RegExp(emojiReplacementRegex, "g"), replacementFunction)
    .replace(textEmojiRegex(opts.inlineEmoji), replacementFunction);
}

export function isCustomEmoji(code, opts) {
  code = code.toLowerCase();
  if (extendedEmoji.hasOwnProperty(code)) {
    return true;
  }
  if (opts && opts.customEmoji && opts.customEmoji.hasOwnProperty(code)) {
    return true;
  }
  return false;
}

export function buildEmojiUrl(code, opts) {
  let url;
  code = String(code).toLowerCase();
  if (extendedEmoji.hasOwnProperty(code)) {
    url = extendedEmoji[code].url;
  }

  if (opts && opts.customEmoji && opts.customEmoji[code]) {
    url = opts.customEmoji[code].url || opts.customEmoji[code];
  }

  const noToneMatch = code.match(/([^:]+):?/);

  let emojiBasePath = "/images/emoji";
  if (opts.emojiCDNUrl) {
    emojiBasePath = opts.emojiCDNUrl;
  }

  if (
    noToneMatch &&
    !url &&
    (emojiHash.hasOwnProperty(noToneMatch[1]) ||
      aliasHash.hasOwnProperty(noToneMatch[1]))
  ) {
    url = opts.getURL(
      `${emojiBasePath}/${opts.emojiSet}/${code.replace(/:t/, "/")}.png`
    );
  }

  if (url) {
    url = url + "?v=" + IMAGE_VERSION;
  }

  return url;
}

export function emojiExists(code) {
  code = code.toLowerCase();
  return !!(
    extendedEmoji.hasOwnProperty(code) ||
    emojiHash.hasOwnProperty(code) ||
    aliasHash.hasOwnProperty(code)
  );
}

let toSearch;
export function emojiSearch(term, options) {
  const maxResults = (options && options["maxResults"]) || -1;
  const diversity = options && options.diversity;
  if (maxResults === 0) {
    return [];
  }

  toSearch =
    toSearch ||
    [
      ...Object.keys(emojiHash),
      ...Object.keys(extendedEmoji),
      ...Object.keys(aliasHash),
    ].sort();

  const results = [];

  function addResult(t) {
    const val = aliasHash[t] || t;
    if (results.indexOf(val) === -1) {
      if (diversity && diversity > 1 && isSkinTonableEmoji(val)) {
        results.push(`${val}:t${diversity}`);
      } else {
        results.push(val);
      }
    }
  }

  // if term matches from beginning
  for (let i = 0; i < toSearch.length; i++) {
    const item = toSearch[i];
    if (item.indexOf(term) === 0) {
      addResult(item);
    }
  }

  for (const [key, value] of Object.entries(searchAliases)) {
    if (key.startsWith(term)) {
      for (const emoji of value) {
        addResult(emoji);
      }
    }
  }

  for (let i = 0; i < toSearch.length; i++) {
    const item = toSearch[i];
    if (item.indexOf(term) > 0) {
      addResult(item);
    }
  }

  if (maxResults === -1) {
    return results;
  } else {
    return results.slice(0, maxResults);
  }
}

export function isSkinTonableEmoji(term) {
  const match = term.split(":").filter(Boolean)[0];
  if (match) {
    return tonableEmojis.indexOf(match) !== -1;
  }
  return false;
}