Remove dashboard usage of cart and itemlist VMs

WooCommerce/Classes/POS/PointOfSaleAggregateModel.swift

@@ -24,6 +24,7 @@ final class PointOfSaleAggregateModel: ObservableObject {
     @Published private(set) var order: Order? = nil
     @Published private(set) var connectionStatus: CardPresentPaymentReaderConnectionStatus = .disconnected
     @Published private(set) var paymentState: PointOfSalePaymentState = .acceptingCard
+    @Published private(set) var itemListState: PointOfSaleItemListState = .initialLoading
 
     private let orderService: POSOrderServiceProtocol
     let cardPresentPaymentService: CardPresentPaymentFacade
@@ -57,13 +58,45 @@ final class PointOfSaleAggregateModel: ObservableObject {
     }
 
     @MainActor
-    func loadItems(pageNumber: Int) async throws {
+    func loadInitialItems() async {
+        do {
+            itemListState = .initialLoading
+            try await fetchItems(pageNumber: 1)
+        } catch {
+            itemListState = .error(PointOfSaleErrorState.errorOnLoadingProducts())
+        }
+    }
+
+    @MainActor
+    func loadItems(pageNumber: Int) async {
+        do {
+            itemListState = .loading
+            try await fetchItems(pageNumber: pageNumber)
+        } catch {
+            itemListState = .error(PointOfSaleErrorState.errorOnLoadingProducts())
+        }
+    }
+
+    @MainActor
+    private func fetchItems(pageNumber: Int) async throws {
         let newItems = try await itemProvider.providePointOfSaleItems(pageNumber: pageNumber)
         let uniqueNewItems = newItems.filter { newItem in
             !allItems.contains(where: { $0.productID == newItem.productID })
         }
 
         allItems.append(contentsOf: uniqueNewItems)
+
+        if allItems.count == 0 {
+            itemListState = .empty
+        } else {
+            itemListState = .loaded(allItems)
+        }
+    }
+
+    @MainActor
+    func reloadItems() async {
+        removeAllItems()
+        await loadItems(pageNumber: 1)
     }
 
     func removeAllItems() {
@@ -257,3 +290,33 @@ extension PointOfSaleAggregateModel {
         }
     }
 }
+
+struct PointOfSaleErrorState: Equatable {
+    let title: String
+    let subtitle: String
+    let buttonText: String
+
+    static func errorOnLoadingProducts() -> Self {
+        PointOfSaleErrorState(title: Constants.failedToLoadTitle,
+                              subtitle: Constants.failedToLoadSubtitle,
+                              buttonText: Constants.failedToLoadButtonTitle)
+    }
+
+    enum Constants {
+        static let failedToLoadTitle = NSLocalizedString(
+            "pos.itemList.failedToLoadTitle",
+            value: "Error loading products",
+            comment: "Text appearing on the item list screen when there's an error loading products."
+        )
+        static let failedToLoadSubtitle = NSLocalizedString(
+            "pos.itemList.failedToLoadSubtitle",
+            value: "Give it another go?",
+            comment: "Text appearing on the item list screen as subtitle when there's an error loading products."
+        )
+        static let failedToLoadButtonTitle = NSLocalizedString(
+            "pos.itemList.failedToLoadButtonTitle",
+            value: "Retry",
+            comment: "Text for the button appearing on the item list screen when there's an error loading products."
+        )
+    }
+}

WooCommerce/Classes/POS/PointOfSaleItemListState.swift

@@ -0,0 +1,54 @@
+import protocol Yosemite.POSItem
+
+enum PointOfSaleItemListState: Equatable {
+    case empty
+    case initialLoading
+    case loading
+    case loaded([POSItem])
+    case error(PointOfSaleErrorState)
+
+    var isLoaded: Bool {
+        switch self {
+        case .loaded:
+            return true
+        default:
+            return false
+        }
+    }
+
+    var isLoading: Bool {
+        switch self {
+        case .loading:
+            return true
+        default:
+            return false
+        }
+    }
+
+    var hasError: PointOfSaleErrorState {
+        switch self {
+        case .error(let errorModel):
+            return errorModel
+        default:
+            return PointOfSaleErrorState(title: "Unknown error",
+                                         subtitle: "Unknown error",
+                                         buttonText: "Retry")
+        }
+    }
+
+    // Equatable conformance for testing:
+    static func == (lhs: PointOfSaleItemListState, rhs: PointOfSaleItemListState) -> Bool {
+        switch (lhs, rhs) {
+        case (.initialLoading, .initialLoading),
+            (.empty, .empty),
+            (.loading, .loading):
+            return true
+        case (.loaded(let lhsItems), .loaded(let rhsItems)):
+            return lhsItems.map { $0.itemID } == rhsItems.map { $0.itemID }
+        case (.error(let lhsError), .error(let rhsError)):
+            return lhsError == rhsError
+        default:
+            return false
+        }
+    }
+}

WooCommerce/Classes/POS/Presentation/CardReaderConnection/UI States/PointOfSaleItemListErrorView.swift

@@ -1,10 +1,10 @@
 import SwiftUI
 
 struct PointOfSaleItemListErrorView: View {
-    private var error: ItemListViewModel.ErrorModel
+    private var error: PointOfSaleErrorState
     private var onRetry: (() -> Void)? = nil
 
-    init(error: ItemListViewModel.ErrorModel, onRetry: (() -> Void)? = nil) {
+    init(error: PointOfSaleErrorState, onRetry: (() -> Void)? = nil) {
         self.error = error
         self.onRetry = onRetry
     }

WooCommerce/Classes/POS/Presentation/CartView.swift

@@ -11,11 +11,26 @@ struct CartView: View {
     @Environment(\.colorScheme) var colorScheme
 
     @State private var offSetPosition: CGFloat = 0.0
+
     private var coordinateSpace: CoordinateSpace = .named(Constants.scrollViewCoordinateSpaceIdentifier)
+
     private var shouldApplyHeaderBottomShadow: Bool {
         !posModel.cart.isEmpty && offSetPosition < 0
     }
 
+    private var isAddMoreDisabled: Bool {
+        switch posModel.paymentState {
+        case .processingPayment,
+                .paymentError,
+                .cardPaymentSuccessful,
+                .validatingOrder,
+                .preparingReader:
+            return true
+        case .idle, .validatingOrderError, .acceptingCard:
+            return posModel.orderState.isSyncing
+        }
+    }
+
     init(posModel: PointOfSaleAggregateModel,
          viewModel: PointOfSaleDashboardViewModel,
          cartViewModel: CartViewModel) {
@@ -29,8 +44,8 @@ struct CartView: View {
             DynamicHStack(spacing: Constants.cartHeaderSpacing) {
                 HStack(spacing: Constants.cartHeaderElementSpacing) {
                     backAddMoreButton
-                        .disabled(viewModel.isAddMoreDisabled)
-                        .shimmering(active: viewModel.isAddMoreDisabled)
+                        .disabled(isAddMoreDisabled)
+                        .shimmering(active: isAddMoreDisabled)
 
                     HStack {
                         Text(Localization.cartTitle)
@@ -267,9 +282,6 @@ import class WooFoundation.MockAnalyticsProviderPreview
     let itemsListViewModel = ItemListViewModel(posModel: posModel)
     let dashboardViewModel = PointOfSaleDashboardViewModel(
         posModel: posModel,
-        totalsViewModel: totalsViewModel,
-        cartViewModel: cartViewModel,
-        itemListViewModel: itemsListViewModel,
         connectivityObserver: POSConnectivityObserverPreview())
     CartView(posModel: posModel,
              viewModel: dashboardViewModel,

WooCommerce/Classes/POS/Presentation/ItemListView.swift

@@ -3,18 +3,24 @@ import protocol Yosemite.POSItem
 
 struct ItemListView: View {
     @ObservedObject var viewModel: ItemListViewModel
+    @ObservedObject var posModel: PointOfSaleAggregateModel
     @Environment(\.floatingControlAreaSize) var floatingControlAreaSize: CGSize
     @Environment(\.dynamicTypeSize) private var dynamicTypeSize
 
-    init(viewModel: ItemListViewModel) {
+    init(viewModel: ItemListViewModel,
+         posModel: PointOfSaleAggregateModel) {
         self.viewModel = viewModel
+        self.posModel = posModel
     }
 
     var body: some View {
         VStack {
             headerView
-            switch viewModel.state {
-            case .empty, .error:
+                .posModal(isPresented: $viewModel.showSimpleProductsModal) {
+                    SimpleProductsOnlyInformation(isPresented: $viewModel.showSimpleProductsModal)
+                }
+            switch posModel.itemListState {
+            case .initialLoading, .empty, .error:
                 // These cases are handled directly in the dashboard, we do not render
                 // a specific view within the ItemListView to handle them
                 EmptyView()
@@ -23,7 +29,7 @@ struct ItemListView: View {
             }
         }
         .refreshable {
-            await viewModel.reload()
+            await posModel.reloadItems()
         }
         .background(Color.posPrimaryBackground)
         .accessibilityElement(children: .contain)
@@ -136,7 +142,7 @@ private extension ItemListView {
             .background(GeometryReader { proxy in
                 Color.clear
                     .onChange(of: proxy.frame(in: .global).maxY) { maxY in
-                        if viewModel.state == .loading {
+                        if posModel.itemListState == .loading {
                             return
                         }
                         let viewHeight = UIScreen.main.bounds.height
@@ -210,6 +216,7 @@ import class WooFoundation.MockAnalyticsPreview
         cardPresentPaymentService: CardPresentPaymentPreviewService(),
         orderService: POSOrderPreviewService(),
         analytics: MockAnalyticsPreview())
-    ItemListView(viewModel: ItemListViewModel(posModel: posModel))
+    ItemListView(viewModel: ItemListViewModel(posModel: posModel),
+                 posModel: posModel)
 }
 #endif

WooCommerce/Classes/POS/Presentation/POSFloatingControlView.swift

@@ -7,6 +7,21 @@ struct POSFloatingControlView: View {
     @Binding var showExitPOSModal: Bool
     @Binding var showSupport: Bool
 
+    private var isExitPOSDisabled: Bool {
+        switch posModel.paymentState {
+        case .processingPayment:
+            return true
+        case .idle,
+                .acceptingCard,
+                .validatingOrder,
+                .validatingOrderError,
+                .preparingReader,
+                .paymentError,
+                .cardPaymentSuccessful:
+            return false
+        }
+    }
+
     init(posModel: PointOfSaleAggregateModel,
          showExitPOSModal: Binding<Bool>,
          showSupport: Binding<Bool>) {
@@ -46,7 +61,7 @@ struct POSFloatingControlView: View {
             }
             .background(backgroundColor)
             .cornerRadius(Constants.cornerRadius)
-            .disabled(posModel.paymentState.cardHasBeenTapped)
+            .disabled(isExitPOSDisabled)
 
             CardReaderConnectionStatusView(posModel: posModel)
                 .foregroundStyle(fontColor)

WooCommerce/Classes/POS/Presentation/PointOfSaleDashboardView.swift

@@ -3,8 +3,8 @@ import SwiftUI
 struct PointOfSaleDashboardView: View {
     @ObservedObject private var viewModel: PointOfSaleDashboardViewModel
     @ObservedObject private var totalsViewModel: TotalsViewModel
-    @ObservedObject private var cartViewModel: CartViewModel
-    @ObservedObject private var itemListViewModel: ItemListViewModel
+    private let cartViewModel: CartViewModel
+    private let itemListViewModel: ItemListViewModel
 
     @ObservedObject private var posModel: PointOfSaleAggregateModel
 
@@ -27,15 +27,15 @@ struct PointOfSaleDashboardView: View {
 
     var body: some View {
         ZStack(alignment: .bottomLeading) {
-            if viewModel.isInitialLoading {
+            if posModel.itemListState == .initialLoading {
                 PointOfSaleLoadingView()
                     .transition(.opacity)
                     .ignoresSafeArea()
             } else if viewModel.isError {
-                let errorContents = viewModel.itemListViewModel.state.hasError
+                let errorContents = posModel.itemListState.hasError
                 PointOfSaleItemListErrorView(error: errorContents, onRetry: {
                     Task {
-                        await viewModel.itemListViewModel.reload()
+                        await posModel.reloadItems()
                     }
                 })
             } else if viewModel.isEmpty {
@@ -51,7 +51,7 @@ struct PointOfSaleDashboardView: View {
                 .offset(x: Constants.floatingControlHorizontalOffset, y: -Constants.floatingControlVerticalOffset)
                 .trackSize(size: $floatingSize)
                 .accessibilitySortPriority(1)
-                .renderedIf(!viewModel.isInitialLoading)
+                .renderedIf(posModel.itemListState != .initialLoading)
 
             POSConnectivityView()
                 .frame(maxWidth: .infinity, maxHeight: .infinity, alignment: .top)
@@ -63,7 +63,7 @@ struct PointOfSaleDashboardView: View {
                       CGSizeMake(floatingSize.width + Constants.floatingControlHorizontalOffset,
                                  floatingSize.height + Constants.floatingControlVerticalOffset))
         .environment(\.posBackgroundAppearance, posModel.paymentState != .processingPayment ? .primary : .secondary)
-        .animation(.easeInOut, value: viewModel.isInitialLoading)
+        .animation(.easeInOut, value: posModel.itemListState == .initialLoading)
         .animation(.easeInOut(duration: Constants.connectivityAnimationDuration), value: viewModel.showsConnectivityError)
         .background(Color.posPrimaryBackground)
         .navigationBarBackButtonHidden(true)
@@ -77,9 +77,6 @@ struct PointOfSaleDashboardView: View {
             PointOfSaleCardPresentPaymentAlert(alertType: alertType)
                 .posInteractiveDismissDisabled(alertType.isDismissDisabled)
         }
-        .posModal(isPresented: $itemListViewModel.showSimpleProductsModal) {
-            SimpleProductsOnlyInformation(isPresented: $itemListViewModel.showSimpleProductsModal)
-        }
         .posModal(isPresented: $showExitPOSModal) {
             PointOfSaleExitPosAlertView(isPresented: $showExitPOSModal)
             .frame(maxWidth: Constants.exitPOSSheetMaxWidth)
@@ -89,7 +86,7 @@ struct PointOfSaleDashboardView: View {
             supportForm
         }
         .task {
-            await viewModel.itemListViewModel.loadInitialItems()
+            await posModel.loadInitialItems()
         }
     }
 
@@ -214,7 +211,7 @@ private extension PointOfSaleDashboardView {
     }
 
     var productListView: some View {
-        ItemListView(viewModel: itemListViewModel)
+        ItemListView(viewModel: itemListViewModel, posModel: posModel)
     }
 }
 
@@ -237,9 +234,6 @@ import class WooFoundation.MockAnalyticsProviderPreview
     let itemsListVM = ItemListViewModel(posModel: posModel)
     let posVM = PointOfSaleDashboardViewModel(
         posModel: posModel,
-        totalsViewModel: totalsVM,
-        cartViewModel: cartVM,
-        itemListViewModel: itemsListVM,
         connectivityObserver: POSConnectivityObserverPreview())
 
     NavigationStack {

WooCommerce/Classes/POS/Presentation/PointOfSaleEntryPointView.swift

@@ -38,9 +38,6 @@ struct PointOfSaleEntryPointView: View {
 
         self._viewModel = StateObject(wrappedValue: PointOfSaleDashboardViewModel(
             posModel: posModel,
-            totalsViewModel: totalsViewModel,
-            cartViewModel: cartViewModel,
-            itemListViewModel: itemListViewModel,
             connectivityObserver: ServiceLocator.connectivityObserver)
         )
         self._cartViewModel = StateObject(wrappedValue: cartViewModel)