@atlaskit/editor-plugin-card/dist/es2019/ui/analytics/create-events-queue.js

Card plugin for @atlaskit/editor-core

/**
 * Simple mechanism to defer event related callbacks
 *
 * Probably think twice whether your event should use this instead of
 * editor's built-in `editor-plugin-analytics`
 *
 * Editor-Plugin-Analytics provides methods methods to dispatch events, and attach events into prosemiror transactions
 * However we do not have access to the smart card context in prosemirror
 *
 * We are using this queue to relay events occurring in prosemirror (which does not have access to the react context)
 * to be subscribed to elsewhere where the react context is available (contentComponent or otherwise) (smart card context)
 * in order to be able to annotate events with additional attributes to events
 */
export const createEventsQueue = () => {
  const queue = [];
  const subscribers = new Set();
  const subscribe = subscriber => {
    subscribers.add(subscriber);
    return () => {
      subscribers.delete(subscriber);
    };
  };
  const push = (...events) => {
    queue.push(...events);
  };
  const flush = () => {
    while (queue.length) {
      const event = queue.shift();
      if (event) {
        subscribers.forEach(subscriber => {
          subscriber(event);
        });
      }
    }
  };
  const getSize = () => queue.length;
  return {
    push,
    flush,
    subscribe,
    getSize
  };
};