slack-christmas-fun.js

(function() {
  "use strict";

  const ACTION_INTERVAL = 250;
  let christmasEmojiTypes = ['snowflake', 'christmas_tree', 'snowman', 'snow_cloud'];

  function getEmogies(container, type, reacted = '') {
    if (reacted) {
      reacted = ':not(.user_reacted)';
    }
    return $(container).find(`[data-emoji="${type}"]${reacted}`);
  }

  function modifyEmoji(container, type, isAddAction) {
    let selectorModifier = '.user_reacted';
    if (isAddAction) {
      selectorModifier = ':not(.user_reacted)';
    }

    $(container).find(`[data-emoji="${type}"]${selectorModifier}`).click();

    return () => new Promise((resolve) => setTimeout(resolve, ACTION_INTERVAL));
  }

  function addEmoji(container, type) {
    return () => new Promise((resolve) => {
      let $addReaction = $(container).find('.ts_icon_add_reaction');
      if (!$addReaction.length) {
        return resolve();
      }

      $addReaction.click();
      let tryCount = 0;
      let interval = setInterval(() => {
        tryCount++
        if (tryCount == 2) {
          $(container).find('.ts_icon_add_reaction');
        }
        if (tryCount > 4) {
          clearInterval(interval);
          return resolve();
        }
        if ($('#emoji_menu').length && $(`[data-name=":${type}:"]`).length) {
          clearInterval(interval);
          $(`[data-name=":${type}:"]`).click();
          setTimeout(resolve, ACTION_INTERVAL);
        }
      }, 50);
    })
  }


  function getFunPromiseList() {
    let funPromiseList = [];
    christmasEmojiTypes.forEach((type) => {
      $('ts-message').slice(-15).each((i, message) => {
        let action;
        let emogies = getEmogies(message, type);
        if (!emogies.length) {
          if (Math.random() < 0.7) {
            action = addEmoji(message, type);
          }
        } else {
          action = modifyEmoji(message, type, Math.random() < 0.2);
        }

        if (action) {
          funPromiseList.push(action);
        }
      });
    });

    return funPromiseList;
  }

  function runChristmasFun() {
    let chain = getFunPromiseList().reduce((chain, promise) => {
      return chain = chain.then(promise);
    }, Promise.resolve());
    chain.then(() => { setTimeout(runChristmasFun, ACTION_INTERVAL * 2); });
  }

  if (!window.jQuery) {
    let script = document.createElement("SCRIPT");
    script.src = 'https://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js';
    script.type = 'text/javascript';
    document.getElementsByTagName("head")[0].appendChild(script);
  }

  let checkReady = function(callback) {
    if (window.jQuery) {
      callback(jQuery);
    }
    else {
      setTimeout(function() { checkReady(callback); }, ACTION_INTERVAL);
    }
  };

  checkReady(function($) {
    runChristmasFun();
  });
  
})();