handleUrlOverride static method

Future<NavigationDecision> handleUrlOverride(NavigationRequest request, LeanCallback? callback)

Implementation

static Future<NavigationDecision> handleUrlOverride(
  NavigationRequest request,
  LeanCallback? callback,
) async {
  final uri = Uri.parse(request.url);

  if (request.url.contains('https://cdn.leantech.me/link/loader')) {
    // Treat the loader as a new session; reset the redirect guard.
    _redirectFired = false;
    return NavigationDecision.navigate;
  }

  // Allow internal WKWebView schemes that may appear during loads.
  if (uri.scheme == 'about' || uri.scheme == 'data' || uri.scheme == 'blob') {
    return NavigationDecision.navigate;
  }

  // Handle Lean custom-scheme callbacks (success/error/cancelled/redirect).
  if (uri.scheme == 'leanlink') {
    LeanLogger.info(msg: 'Lean deep-link received: ${request.url}');

    // If the host is a generic redirect marker, return a canned success;
    // otherwise parse full details from the query string.
    if (uri.host == 'redirect') {
      LeanLogger.info(msg: 'Redirect received: ${request.url}');
      _redirectFired = true; // guard against late duplicates
      callback?.call(LeanResponse(
        status: 'SUCCESS',
        message: 'Link closed after redirect',
      ));
    } else {
      LeanLogger.info(msg: 'Response received: ${request.url}');
      callback?.call(_getResponseFromParams(uri));
    }
    return NavigationDecision.prevent;
  }

  // External handoff:
  // When leaving the WebView (e.g., to Safari for Open Banking),
  // WKWebView suspends JavaScript immediately. Any callback
  // scheduled after the hop (such as window.open('leanlink://redirect'))
  // may never run — especially on iOS when the redirect path is fast
  // due to caching or preconnect.
  //
  // To avoid losing callbacks, we always launch externally and issue
  // a manual fallback callback if no real leanlink:// event was received.
  LeanLogger.info(msg: 'Opening URL in external browser: ${request.url}');
  final launched = await launchUrl(uri, mode: LaunchMode.externalApplication);

  if (launched) {
    if (!_redirectFired) {
      LeanLogger.info(
          msg: 'No leanlink callback detected → issuing manual fallback');
      _redirectFired = true; // set manual call to avoid potential double-fire
      callback?.call(LeanResponse(
        status: 'SUCCESS',
        message: 'Link closed after redirect',
      ));
    }
  } else {
    LeanLogger.info(msg: 'External launch failed: ${request.url}');
  }

  // Prevent WebView navigation for external URLs; we've handled them.
  return NavigationDecision.prevent;
}