@streambird/streambird-js/src/loader.ts

Streambird SDK

import { StreambirdFactory } from './types';
import { STREAMBIRD_JS_URL } from './constants';

const findOrCreateScript = (): HTMLScriptElement => {
  const scripts = document.querySelectorAll<HTMLScriptElement>(`script[src="${STREAMBIRD_JS_URL}"]`);

  if (scripts[0]) {
    return scripts[0];
  }

  const script = document.createElement('script');
  script.src = STREAMBIRD_JS_URL;
  document.head.appendChild(script);
  return script;
};

const loadScript = (): Promise<StreambirdFactory | null> => {
  const isBrowser = typeof window !== 'undefined' && typeof window.document !== 'undefined';

  if (!isBrowser) {
    return Promise.resolve(null);
  }

  return new Promise((resolve, reject) => {
    if (window.Streambird) {
      console.warn('Streambird.js has already been loaded');
      resolve(window.Streambird);
    }

    const script = findOrCreateScript();

    script.addEventListener('load', () => {
      if (window.Streambird) {
        resolve(window.Streambird);
      } else {
        reject(new Error('Streambird.js could not be loaded'));
      }
    });

    script.addEventListener('error', () => {
      reject(new Error('Streambird.js could not be loaded'));
    });
  });
};

const streambirdPromise: Promise<StreambirdFactory | null> = Promise.resolve().then(() => loadScript());

let loadCalled = false;

streambirdPromise.catch((err: Error) => {
  if (!loadCalled) {
    console.warn(err);
  }
});

export const loadStreambird = (): Promise<StreambirdFactory | null> => {
  loadCalled = true;
  return streambirdPromise;
};