getCheckoutUrl method

Implementation

@override
Future<String> getCheckoutUrl(PaymentRequest request) async {
  try {
    request.validate();
    final result = await methodChannel.invokeMethod<Map<dynamic, dynamic>>(
      'getCheckoutUrl',
      request.toJson(),
    );
    if (result == null) {
      throw PaystackError(message: 'No response from checkout URL request');
    }
    final castedResult = result.cast<String, dynamic>();
    if (castedResult['status'] != 'success') {
      throw PaystackError.fromApiResponse(castedResult);
    }
    final data = castedResult['data'] as Map<String, dynamic>;
    final checkoutUrl = data['authorization_url'] as String?;
    if (checkoutUrl == null) {
      throw PaystackError(message: 'No checkout URL in response');
    }
    return checkoutUrl;
  } on PlatformException catch (e) {
    throw PaystackError(
      message: e.message ?? 'Failed to get checkout URL',
      code: e.code,
    );
  }
}