[Notify] Messages pagination

Example/IntegrationTests/Push/NotifyTests.swift

@@ -264,8 +264,9 @@ final class NotifyTests: XCTestCase {
 
         await fulfillment(of: [subscribeExpectation], timeout: InputConfig.defaultTimeout)
 
-        try await walletNotifyClientA.fetchHistory(subscription: subscription)
-        XCTAssertTrue(walletNotifyClientA.getMessageHistory(topic: subscription.topic).count > 40)
+        let hasMore = try await walletNotifyClientA.fetchHistory(subscription: subscription, after: nil, limit: 20)
+        XCTAssertTrue(hasMore)
+        XCTAssertTrue(walletNotifyClientA.getMessageHistory(topic: subscription.topic).count == 20)
     }
 }
 

Example/WalletApp/PresentationLayer/Wallet/PushMessages/SubscriptionInteractor.swift

@@ -31,9 +31,7 @@ final class SubscriptionInteractor {
         }
     }
 
-    func fetchHistory() {
-        Task(priority: .high) {
-            try await Notify.instance.fetchHistory(subscription: subscription)
-        }
+    func fetchHistory(after: String?, limit: Int) async throws -> Bool {
+        return try await Notify.instance.fetchHistory(subscription: subscription, after: after, limit: limit)
     }
 }

Example/WalletApp/PresentationLayer/Wallet/PushMessages/SubscriptionPresenter.swift

@@ -4,13 +4,21 @@ import WalletConnectNotify
 
 final class SubscriptionPresenter: ObservableObject {
 
+    enum LoadingState {
+        case loading
+        case idle
+    }
+
     private var subscription: NotifySubscription
     private let interactor: SubscriptionInteractor
     private let router: SubscriptionRouter
     private var disposeBag = Set<AnyCancellable>()
 
     @Published private var pushMessages: [NotifyMessageRecord] = []
 
+    @Published var loadingState: LoadingState = .idle
+    @Published var isMoreDataAvailable: Bool = true
+
     var subscriptionViewModel: SubscriptionsViewModel {
         return SubscriptionsViewModel(subscription: subscription)
     }
@@ -49,6 +57,19 @@ final class SubscriptionPresenter: ObservableObject {
         router.dismiss()
     }
 
+    func loadMoreMessages() {
+        switch loadingState {
+        case .loading:
+            break
+        case .idle:
+            Task(priority: .high) { @MainActor in
+                loadingState = .loading
+                isMoreDataAvailable = try await interactor.fetchHistory(after: messages.last?.id, limit: 50)
+                loadingState = .idle
+            }
+        }
+    }
+
     @objc func preferencesDidPress() {
         router.presentPreferences(subscription: subscription)
     }
@@ -77,8 +98,6 @@ extension SubscriptionPresenter: SceneViewModel {
 private extension SubscriptionPresenter {
 
     func setupInitialState() {
-        interactor.fetchHistory()
-
         pushMessages = interactor.getPushMessages()
 
         interactor.messagesPublisher

Example/WalletApp/PresentationLayer/Wallet/PushMessages/SubscriptionView.swift

@@ -34,6 +34,11 @@ struct SubscriptionView: View {
                         .listRowSeparator(.hidden)
                         .listRowBackground(Color.clear)
                 }
+
+                if presenter.isMoreDataAvailable {
+                    lastRowView()
+                        .listRowSeparator(.hidden)
+                }
             }
             .listStyle(PlainListStyle())
         }
@@ -161,6 +166,26 @@ struct SubscriptionView: View {
         .frame(maxWidth: .infinity)
         .frame(height: 410)
     }
+
+    func lastRowView() -> some View {
+        VStack {
+            switch presenter.loadingState {
+            case .loading:
+                HStack {
+                    Spacer()
+                    ProgressView()
+                    Spacer()
+                }
+                .padding(.bottom, 24)
+            case .idle:
+                EmptyView()
+            }
+        }
+        .frame(height: 50)
+        .onAppear {
+            presenter.loadMoreMessages()
+        }
+    }
 }
 
 #if DEBUG

Sources/WalletConnectNotify/Client/Wallet/HistoryService.swift

@@ -12,7 +12,7 @@ public final class HistoryService {
         self.identityClient = identityClient
     }
 
-    public func fetchHistory(account: Account, topic: String, appAuthenticationKey: String, host: String) async throws -> [NotifyMessage] {
+    public func fetchHistory(account: Account, topic: String, appAuthenticationKey: String, host: String, after: String?, limit: Int) async throws -> [NotifyMessage] {
         let dappAuthKey = try DIDKey(did: appAuthenticationKey)
         let app = DIDWeb(host: host)
 
@@ -21,8 +21,8 @@ public final class HistoryService {
             keyserver: keyserver.absoluteString,
             dappAuthKey: dappAuthKey,
             app: app,
-            limit: 50,
-            after: nil
+            limit: UInt64(limit),
+            after: after
         )
 
         let wrapper = try identityClient.signAndCreateWrapper(payload: requestPayload, account: account)

Sources/WalletConnectNotify/Client/Wallet/NotifyClient.swift

@@ -148,19 +148,23 @@ public class NotifyClient {
         return notifyStorage.messagesPublisher(topic: topic)
     }
 
-    public func fetchHistory(subscription: NotifySubscription) async throws {
+    public func fetchHistory(subscription: NotifySubscription, after: String?, limit: Int) async throws -> Bool {
         let messages = try await historyService.fetchHistory(
             account: subscription.account,
             topic: subscription.topic,
             appAuthenticationKey: subscription.appAuthenticationKey,
-            host: subscription.metadata.url
+            host: subscription.metadata.url, 
+            after: after, 
+            limit: limit
         )
 
         let records = messages.map { message in
             return NotifyMessageRecord(topic: subscription.topic, message: message, publishedAt: message.sentAt)
         }
 
         try notifyStorage.setMessages(records)
+
+        return messages.count == limit
     }
 }