Merge neurons

frontend/dart/lib/ic_api/platform_ic_api.dart

@@ -68,6 +68,9 @@ abstract class AbstractPlatformICApi {
       required ICP amount,
       required String? toAccountId});
 
+  Future<Result<Unit, Exception>> merge(
+      {required Neuron neuron1, required Neuron neuron2});
+
   Future<Result<Unit, Exception>> mergeMaturity(
       {required Neuron neuron, required int percentageToMerge});
 

frontend/dart/lib/ic_api/web/service_api.dart

@@ -106,6 +106,9 @@ class ServiceApi {
   @JS("disburseToNeuron")
   external Promise<dynamic> disburseToNeuron(dynamic request);
 
+  @JS("merge")
+  external Promise<dynamic> merge(dynamic identity, dynamic request);
+
   @JS("mergeMaturity")
   external Promise<dynamic> mergeMaturity(dynamic identity, dynamic request);
 
@@ -223,6 +226,16 @@ class DisburseNeuronRequest {
       {dynamic neuronId, dynamic amount, String? toAccountId});
 }
 
+@JS()
+@anonymous
+class MergeRequest {
+  external dynamic neuronId;
+  external dynamic sourceNeuronId;
+
+  external factory MergeRequest(
+      {dynamic neuronId, dynamic sourceNeuronId});
+}
+
 @JS()
 @anonymous
 class MergeMaturityRequest {

frontend/dart/lib/ic_api/web/web_ic_api.dart

@@ -224,6 +224,59 @@ class PlatformICApi extends AbstractPlatformICApi {
     }
   }
 
+  @override
+  Future<Result<Unit, Exception>> merge(
+      {required Neuron neuron1, required Neuron neuron2}) async {
+    try {
+      final identity1 = (await getIdentityByNeuron(neuron1)).unwrap();
+      final identity2 = (await getIdentityByNeuron(neuron2)).unwrap();
+
+      if (identity1.getPrincipal().toString() != identity2.getPrincipal().toString()) {
+        return Result.err(Exception("The neurons being merged must both have the same controller"));
+      }
+
+      // To ensure any built up age bonus is always preserved, if one neuron is
+      // locked and the other is not, then we merge the neuron which is not
+      // locked into the locked neuron.
+      // In all other cases we merge the smaller neuron into the
+      // larger one.
+
+      final neuron1Locked = neuron1.state == NeuronState.LOCKED;
+      final neuron2Locked = neuron2.state == NeuronState.LOCKED;
+
+      Neuron targetNeuron;
+      Neuron sourceNeuron;
+      if (neuron1Locked != neuron2Locked) {
+        if (neuron1Locked) {
+          targetNeuron = neuron1;
+          sourceNeuron = neuron2;
+        } else {
+          targetNeuron = neuron2;
+          sourceNeuron = neuron1;
+        }
+      } else {
+        if (neuron1.cachedNeuronStake.asE8s() >= neuron2.cachedNeuronStake.asE8s()) {
+          targetNeuron = neuron1;
+          sourceNeuron = neuron2;
+        } else {
+          targetNeuron = neuron2;
+          sourceNeuron = neuron1;
+        }
+      }
+
+      await promiseToFuture(serviceApi!.merge(
+          identity1,
+          MergeRequest(
+              neuronId: targetNeuron.id.toBigInt.toJS,
+              sourceNeuronId: sourceNeuron.id.toBigInt.toJS)));
+      await fetchNeuron(neuronId: targetNeuron.id.toBigInt);
+      neuronSyncService!.removeNeuron(sourceNeuron.id.toString());
+      return Result.ok(unit);
+    } catch (err) {
+      return Result.err(Exception(err));
+    }
+  }
+
   @override
   Future<Result<Unit, Exception>> mergeMaturity(
       {required Neuron neuron, required int percentageToMerge}) async {

frontend/dart/lib/ui/neurons/tab/neuron_row.dart

@@ -6,10 +6,8 @@ import '../../../nns_dapp.dart';
 class NeuronRow extends StatelessWidget {
   final Neuron neuron;
   final bool showsWarning;
-  final Function? onTap;
 
-  const NeuronRow(
-      {Key? key, required this.neuron, this.onTap, this.showsWarning = false})
+  const NeuronRow({Key? key, required this.neuron, this.showsWarning = false})
       : super(key: key);
 
   @override
@@ -89,15 +87,20 @@ class NeuronRow extends StatelessWidget {
           Row(
             crossAxisAlignment: CrossAxisAlignment.end,
             children: [
-              Text(
-                  "${neuron.dissolveDelay.yearsDayHourMinuteSecondFormatted()}",
-                  style: context.textTheme.subtitle2),
-              Text(" Dissolve Delay", style: context.textTheme.subtitle2)
+              Expanded(
+                child: Text(
+                    "${neuron.dissolveDelay.yearsDayHourMinuteSecondFormatted()}",
+                    style: context.textTheme.subtitle2),
+              ),
+              Expanded(
+                  flex: 2,
+                  child: Text(" Dissolve Delay",
+                      style: context.textTheme.subtitle2))
             ],
           ),
           SizedBox(
             height: 5,
-          )
+          ),
         ]
       ],
     );

frontend/dart/lib/ui/neurons/tab/neurons_tab_widget.dart

@@ -3,6 +3,7 @@ import 'package:nns_dapp/ui/_components/footer_gradient_button.dart';
 import 'package:nns_dapp/ui/_components/form_utils.dart';
 import 'package:nns_dapp/ui/_components/page_button.dart';
 import 'package:nns_dapp/ui/_components/tab_title_and_content.dart';
+import 'package:nns_dapp/ui/transaction/wallet/merge_neuron_accounts_page.dart';
 import 'package:nns_dapp/ui/transaction/wallet/select_source_wallet_page.dart';
 import 'package:nns_dapp/ui/transaction/wizard_overlay.dart';
 import '../../../nns_dapp.dart';
@@ -16,63 +17,84 @@ class NeuronsPage extends StatefulWidget {
 class _NeuronsPageState extends State<NeuronsPage> {
   @override
   Widget build(BuildContext context) {
-    return FooterGradientButton(
-      footerHeight: null,
-      body: ConstrainWidthAndCenter(
-        child: StreamBuilder<void>(
-            stream: context.boxes.neurons.changes,
-            builder: (context, snapshot) {
-              return TabTitleAndContent(
+    return StreamBuilder<void>(
+        stream: context.boxes.neurons.changes,
+        builder: (context, snapshot) {
+          return FooterGradientButton(
+            footerHeight: null,
+            body: ConstrainWidthAndCenter(
+              child: TabTitleAndContent(
                 title: "Neurons",
                 subtitle:
                     '''Earn rewards by staking your ICP in neurons. Neurons allow you to participate in governance on the Internet Computer by voting on Network Nervous System (NNS) proposals.
-
+                      
 Your principal id is "${context.icApi.getPrincipal()}"''',
                 children: [
                   SmallFormDivider(),
                   ...(context.boxes.neurons.values
-                          ?.sortedByDescending((element) =>
-                              element.createdTimestampSeconds.toBigInt)
+                          ?.sortedByDescending((element) => element.createdTimestampSeconds.toBigInt)
                           .mapToList((e) => Card(
                                 child: TextButton(
                                   onPressed: () {
-                                    context.nav.push(
-                                        neuronPageDef.createPageConfig(e));
+                                    context.nav.push(neuronPageDef.createPageConfig(e));
                                   },
                                   child: Padding(
                                     padding: const EdgeInsets.all(16.0),
                                     child: NeuronRow(
                                       neuron: e,
                                       showsWarning: true,
-                                      onTap: () {
-                                        context.nav.push(
-                                            neuronPageDef.createPageConfig(e));
-                                      },
                                     ),
                                   ),
                                 ),
                               )) ??
                       []),
                   SizedBox(height: 150)
                 ],
-              );
-            }),
-      ),
-      footer: Align(
-        alignment: Alignment.bottomCenter,
-        child: PageButton(
-          title: "Stake Neuron",
-          onPress: () {
-            OverlayBaseWidget.show(
-              context,
-              WizardOverlay(
-                rootTitle: "Select Source Account",
-                rootWidget: SelectSourceWallet(isStakeNeuron: true),
               ),
-            );
-          },
-        ),
-      ),
-    );
+            ),
+            footer: Align(
+              alignment: Alignment.bottomCenter,
+              child: Padding(
+                padding: const EdgeInsets.all(16.0),
+                child: Row(
+                  mainAxisAlignment: MainAxisAlignment.center,
+                  children: [
+                    Flexible(
+                      child: PageButton(
+                        title: "Stake Neuron",
+                        onPress: () {
+                          OverlayBaseWidget.show(
+                            context,
+                            WizardOverlay(
+                              rootTitle: "Select Source Account",
+                              rootWidget: SelectSourceWallet(isStakeNeuron: true),
+                            ),
+                          );
+                        },
+                      ),
+                    ),
+                    Flexible(
+                      child: PageButton(
+                          title: "Merge Neurons",
+                          onPress: () {
+                            OverlayBaseWidget.show(
+                              context,
+                              WizardOverlay(
+                                rootTitle: "Select Two neurons to merge",
+                                rootWidget: MergeNeuronSourceAccount(
+                                  onCompleteAction: (context) {
+                                    OverlayBaseWidget.of(context)?.dismiss();
+                                  },
+                                ),
+                              ),
+                            );
+                          }.takeIf((e) => context.boxes.neurons.values.length >= 2)),
+                    ),
+                  ],
+                ),
+              ),
+            ),
+          );
+        });
   }
 }