Add support for paying BOLT12 offers (#251)

* feat: add support for paying BOLT 12 offers

* chore: export LnOfferPaymentPage route

lib/app/routes/routes.dart

@@ -122,6 +122,16 @@ Route<dynamic>? onGenerateRoute({
                     ),
                     settings: settings,
                   );
+                case LnOfferPaymentPage.routeName:
+                  return FadeInRoute<PrepareSendResponse?>(
+                    builder: (BuildContext context) => BlocProvider<PaymentLimitsCubit>(
+                      create: (BuildContext context) => PaymentLimitsCubit(ServiceInjector().breezSdkLiquid),
+                      child: LnOfferPaymentPage(
+                        lnOffer: settings.arguments as LNOffer,
+                      ),
+                    ),
+                    settings: settings,
+                  );
                 case LnUrlPaymentPage.routeName:
                   return FadeInRoute<PrepareLnUrlPayResponse?>(
                     builder: (BuildContext context) => BlocProvider<PaymentLimitsCubit>(

lib/cubit/input/input_cubit.dart

@@ -95,6 +95,8 @@ class InputCubit extends Cubit<InputState> {
     InputState result;
     if (parsedInput is InputType_Bolt11) {
       result = await handlePaymentRequest(parsedInput, source);
+    } else if (parsedInput is InputType_Bolt12Offer) {
+      result = InputState.bolt12Offer(parsedInput.offer, source);
     } else if (parsedInput is InputType_LnUrlPay) {
       result = InputState.lnUrlPay(parsedInput.data, source);
     } else if (parsedInput is InputType_LnUrlWithdraw) {

lib/cubit/input/input_state.dart

@@ -13,6 +13,11 @@ class InputState {
     InputSource source,
   ) = LnInvoiceInputState;
 
+  const factory InputState.bolt12Offer(
+    LNOffer lnOffer,
+    InputSource source,
+  ) = LnOfferInputState;
+
   const factory InputState.lnUrlPay(
     LnUrlPayRequestData data,
     InputSource source,
@@ -92,7 +97,7 @@ class LnInvoiceInputState extends InputState {
 
   @override
   String toString() {
-    return 'InvoiceInputState{lnInvoice: $lnInvoice, source: $source}';
+    return 'LnInvoiceInputState{lnInvoice: $lnInvoice, source: $source}';
   }
 
   @override
@@ -107,6 +112,32 @@ class LnInvoiceInputState extends InputState {
   int get hashCode => lnInvoice.hashCode ^ source.hashCode;
 }
 
+class LnOfferInputState extends InputState {
+  const LnOfferInputState(
+    this.lnOffer,
+    this.source,
+  ) : super._();
+
+  final LNOffer lnOffer;
+  final InputSource source;
+
+  @override
+  String toString() {
+    return 'LnOfferInputState{lnInvoice: $lnOffer, source: $source}';
+  }
+
+  @override
+  bool operator ==(Object other) =>
+      identical(this, other) ||
+      other is LnOfferInputState &&
+          runtimeType == other.runtimeType &&
+          lnOffer == other.lnOffer &&
+          source == other.source;
+
+  @override
+  int get hashCode => lnOffer.hashCode ^ source.hashCode;
+}
+
 class LnUrlPayInputState extends InputState {
   const LnUrlPayInputState(
     this.data,

lib/handlers/input_handler/src/input_handler.dart

@@ -84,6 +84,8 @@ class InputHandler extends Handler {
 
     if (inputState is LnInvoiceInputState) {
       return handleLnInvoice(context, inputState.lnInvoice);
+    } else if (inputState is LnOfferInputState) {
+      return handleLnOffer(context, inputState.lnOffer);
     } else if (inputState is LnUrlPayInputState) {
       return handlePayRequest(context, firstPaymentItemKey, inputState.data);
     } else if (inputState is LnUrlWithdrawInputState) {
@@ -136,6 +138,41 @@ class InputHandler extends Handler {
     });
   }
 
+  Future<dynamic> handleLnOffer(BuildContext context, LNOffer lnOffer) async {
+    _logger.info('handle LNOffer $lnOffer');
+    final NavigatorState navigator = Navigator.of(context);
+    final PrepareSendResponse? prepareResponse = await navigator.pushNamed<PrepareSendResponse?>(
+      LnOfferPaymentPage.routeName,
+      arguments: lnOffer,
+    );
+    if (prepareResponse == null || !context.mounted) {
+      return Future<dynamic>.value();
+    }
+
+    // Show Processing Payment Dialog
+    return await showDialog(
+      useRootNavigator: false,
+      context: context,
+      barrierDismissible: false,
+      builder: (_) => ProcessingPaymentDialog(
+        isLnUrlPayment: true,
+        firstPaymentItemKey: firstPaymentItemKey,
+        paymentFunc: () async {
+          final PaymentsCubit paymentsCubit = context.read<PaymentsCubit>();
+          return await paymentsCubit.sendPayment(prepareResponse);
+        },
+      ),
+    ).then((dynamic result) {
+      if (result is String && context.mounted) {
+        showFlushbar(context, message: result);
+      }
+      // TODO(erdemyerebasmaz): Handle SendPaymentResponse results, return a SendPaymentResult to be handled by handleResult()
+      if (result is SendPaymentResponse) {
+        _logger.info('SendPaymentResponse result - payment status: ${result.payment.status}');
+      }
+    });
+  }
+
   Future<dynamic> handleBitcoinAddress(BuildContext context, BitcoinAddressInputState inputState) async {
     _logger.fine('handle bitcoin address $inputState');
     if (inputState.source == InputSource.qrcodeReader) {

lib/routes/send_payment/lightning/lightning.dart

@@ -0,0 +1,2 @@
+export 'ln_invoice_payment_page.dart';
+export 'ln_offer_payment_page.dart';