fix onramper network tag plus UI (#1832)

lib/buy/onramper/onramper_buy_provider.dart

@@ -248,9 +248,12 @@ class OnRamperBuyProvider extends BuyProvider {
   String _tagToNetwork(String tag) {
     switch (tag) {
       case 'OMNI':
+      case 'BSC':
         return tag;
       case 'POL':
         return 'POLYGON';
+      case 'ZEC':
+        return 'ZCASH';
     default:
         try {
           return CryptoCurrency.fromString(tag).fullName!;

lib/src/screens/buy/buy_sell_page.dart

@@ -170,8 +170,9 @@ class BuySellPage extends BasePage {
                           },
                           color: Theme.of(context).primaryColor,
                           textColor: Colors.white,
-                          isDisabled: false,
-                          isLoading: !buySellViewModel.isReadyToTrade)),
+                          isDisabled: buySellViewModel.isBuySellQuotFailed,
+                          isLoading: !buySellViewModel.isReadyToTrade &&
+                              !buySellViewModel.isBuySellQuotFailed)),
                 ]),
               )),
         ));

lib/view_model/buy/buy_sell_view_model.dart

@@ -155,13 +155,18 @@ abstract class BuySellViewModelBase extends WalletChangeListenerViewModel with S
     final hasSelectedPaymentMethod = selectedPaymentMethod != null;
     final isPaymentMethodLoaded = paymentMethodState is PaymentMethodLoaded;
     final isBuySellQuotLoaded = buySellQuotState is BuySellQuotLoaded;
+    final isBuySellQuotFailed = buySellQuotState is BuySellQuotFailed;
 
     return hasSelectedQuote &&
         hasSelectedPaymentMethod &&
         isPaymentMethodLoaded &&
-        isBuySellQuotLoaded;
+        isBuySellQuotLoaded &&
+        !isBuySellQuotFailed;
   }
 
+  @computed
+  bool get isBuySellQuotFailed => buySellQuotState is BuySellQuotFailed;
+
   @action
   void reset() {
     cryptoCurrency = wallet.currency;