detectBrowserEngineByVendorAgent method

Implementation

BrowserEngine detectBrowserEngineByVendorAgent(String vendor, String agent) {
  if (vendor == 'Google Inc.') {
    return BrowserEngine.blink;
  } else if (vendor == 'Apple Computer, Inc.') {
    return BrowserEngine.webkit;
  } else if (agent.contains('Edg/')) {
    // Chromium based Microsoft Edge has `Edg` in the user-agent.
    // https://docs.microsoft.com/en-us/microsoft-edge/web-platform/user-agent-string
    return BrowserEngine.blink;
  } else if (vendor == '' && agent.contains('firefox')) {
    // An empty string means firefox:
    // https://developer.mozilla.org/en-US/docs/Web/API/Navigator/vendor
    return BrowserEngine.firefox;
  }

  // Assume Blink otherwise, but issue a warning.
  print(
      'WARNING: failed to detect current browser engine. Assuming this is a Chromium-compatible browser.');
  return BrowserEngine.blink;
}