App changes for Day 65

day-062/Projects/Instafilter/Instafilter/Data/State/FilteredImagesState.swift

@@ -13,37 +13,15 @@ import CypherPoetSwiftUIKit_DataFlowUtils
 
 
 struct FilteredImagesState {
-    var currentInputImage: UIImage?
     var filteredOutputCGImage: CGImage?
-    var filteringErrorMessage: String?
 }
 
 
-enum FilteredImagesSideEffect: SideEffect {
+//enum FilteredImagesSideEffect: SideEffect {}
-    case apply(filter: CIFilter, to: UIImage)
-    
-    func mapToAction() -> AnyPublisher<AppAction, Never> {
-        switch self {
-        case let .apply(filter, inputImage):
-            return ImageFilteringService.shared
-                .apply(filter, to: inputImage)
-                .map { cgImage in
-                    AppAction.filteredImages(.setFilteredOutput(image: cgImage))
-                }
-                .catch { (error: ImageFilteringService.Error) in
-                    // TODO: Better handling here 🙈
-                    Just(AppAction.filteredImages(.setFilteringError(message: "Failed")))
-                }
-                .eraseToAnyPublisher()
-        }
-    }
-}
 
 
 enum FilteredImagesAction {
-    case setCurrentInput(image: UIImage)
     case setFilteredOutput(image: CGImage)
-    case setFilteringError(message: String)
 }
 
 
@@ -51,11 +29,7 @@ enum FilteredImagesAction {
 // MARK: - Reducer
 let filteredImagesReducer = Reducer<FilteredImagesState, FilteredImagesAction> { state, action in
     switch action {
-    case .setCurrentInput(let image):
-        state.currentInputImage = image
     case .setFilteredOutput(let image):
         state.filteredOutputCGImage = image
-    case .setFilteringError(let message):
-        state.filteringErrorMessage = message
     }
 }

day-062/Projects/Instafilter/Instafilter/Scenes/ImageFilteringContainerView.swift

@@ -27,14 +27,18 @@ extension ImageFilteringContainerView {
     var body: some View {
         NavigationView {
             VStack(spacing: 42.0) {
-                Spacer()
+                Group {
-                
+                    if currentInputImage != nil {
-                imageContent
+                        ImageFilteringView(inputImage: currentInputImage!, store: store)
-                    .layoutPriority(1)
+                    } else {
-                
+                        Spacer()
-                imagePickerButton
+                        
-                
+                        imageSelectionSection
-                Spacer()
+                            .padding()
+                        
+                        Spacer()
+                    }
+                }
             }
             .navigationBarTitle("📸 Instafilter")
             .navigationBarItems(trailing: saveButton)
@@ -60,14 +64,13 @@ extension ImageFilteringContainerView {
 // MARK: - View Variables
 extension ImageFilteringContainerView {
     
-    private var imageContent: some View {
+    private var imageSelectionSection: some View {
-        Group {
+        VStack(spacing: 36) {
-            if currentInputImage != nil {
+            Text("Select an Image to begin filtering.")
-                ImageFilteringView(inputImage: currentInputImage!, store: store)
+                .font(.title)
-            } else {
+                .multilineTextAlignment(.center)
-                Text("Select an Image to begin filtering.")
+            
-                    .font(.title)
+            imagePickerButton
-            }
         }
     }
     

day-062/Projects/Instafilter/Instafilter/Scenes/ImageFilteringView.swift

@@ -10,12 +10,18 @@ import SwiftUI
 
 
 struct ImageFilteringView: View {
+    @EnvironmentObject private var store: AppStore
     @ObservedObject private(set) var viewModel: ImageFilteringViewModel
+
+    private let inputImage: UIImage
+    
     
     init(
         inputImage: UIImage,
         store: AppStore
     ) {
+        self.inputImage = inputImage
+        
         self.viewModel = ImageFilteringViewModel(
             inputImage: inputImage,
             store: store
@@ -34,9 +40,15 @@ extension ImageFilteringView {
                 Text(viewModel.filteringErrorMessage!)
             }
 
-            (viewModel.filteredImage ?? Image(uiImage: viewModel.inputImage))
+            (outputImage ?? Image(uiImage: inputImage))
                 .resizable()
                 .scaledToFit()
+            
+            controls
+                .padding()
+                .padding(.top)
+            
+            Spacer()
         }
     }
 }
@@ -44,7 +56,14 @@ extension ImageFilteringView {
 
 // MARK: - Computeds
 extension ImageFilteringView {
-
+    
+    var outputImage: Image? {
+        guard let cgImage = store.state.filteredImages.filteredOutputCGImage else {
+            return nil
+        }
+        
+        return Image(uiImage: UIImage(cgImage: cgImage))
+    }
 
 }
 
@@ -52,7 +71,24 @@ extension ImageFilteringView {
 // MARK: - View Variables
 extension ImageFilteringView {
 
-
+    private var controls: some View {
+        VStack(spacing: 24) {
+            
+            VStack(spacing: 2.0) {
+                Text("Intensity")
+                    .font(.headline)
+                    .fontWeight(.bold)
+                
+                Slider(
+                    value: $viewModel.filterIntensity,
+                    minimumValueLabel: Text("0"),
+                    maximumValueLabel: Text("1")
+                ) {
+                    Text("Intensity")
+                }
+            }
+        }
+    }
 }
 
 
@@ -61,9 +97,12 @@ extension ImageFilteringView {
 struct ImageFilteringView_Previews: PreviewProvider {
 
     static var previews: some View {
-        ImageFilteringView(
+        NavigationView {
-            inputImage: UIImage(named: "earth-night")!,
+            ImageFilteringView(
-            store: SampleStore.default
+                inputImage: UIImage(named: "earth-night")!,
-        )
+                store: SampleStore.default
+            )
+            .environmentObject(SampleStore.default)
+        }
     }
 }

day-062/Projects/Instafilter/Instafilter/Scenes/ImageFilteringViewModel.swift

@@ -19,10 +19,11 @@ final class ImageFilteringViewModel: ObservableObject {
 
     @Published var inputImage: UIImage
     @Published var currentFilter: CIFilter
+    @Published var filterIntensity: CGFloat = 0.0
     
     
     // MARK: - Published Properties
-    @Published var filteredImage: Image?
+//    @Published var filteredImage: Image?
     @Published var filteringErrorMessage: String?
     
     
@@ -43,26 +44,33 @@ final class ImageFilteringViewModel: ObservableObject {
 
 // MARK: - Publishers
 extension ImageFilteringViewModel {
+    
+    private var filteredCGImagePublisher: AnyPublisher<CGImage, ImageFilteringService.Error> {
+        ciFilterPublisher
+            .setFailureType(to: ImageFilteringService.Error.self)
+            .flatMap { filter in
+                ImageFilteringService.shared.apply(filter, to: self.inputImage)
+            }
+            .eraseToAnyPublisher()
+    }
 
-    private var filteredImagesStatePublisher: AnyPublisher<FilteredImagesState, Never> {
+    
-        store.$state
+    private var filterIntensityPublisher: AnyPublisher<CGFloat, Never> {
-            .map(\.filteredImages)
+        $filterIntensity
+            .debounce(for: .milliseconds(200), scheduler: DispatchQueue.main)
             .eraseToAnyPublisher()
     }
   
     
-    private var filteredCGImagePublisher: AnyPublisher<CGImage, Never> {
+    // TODO: Should this create a copy and return it? Should this be used straight-on
-        filteredImagesStatePublisher
+    // instead of the other `currentFilter` property?
-            .map(\.filteredOutputCGImage)
+    var ciFilterPublisher: AnyPublisher<CIFilter, Never> {
-            .compactMap { $0 }
+//        Publishers.CombineLatest(filterIntensityPublisher, )
-            .eraseToAnyPublisher()
+        filterIntensityPublisher
-    }
+            .map {
-  
+                self.currentFilter.setValue($0, forKey: kCIInputIntensityKey)
-    
+                
-    private var filteredImagePublisher: AnyPublisher<Image?, Never> {
+                return self.currentFilter
-        filteredCGImagePublisher
-            .map { cgImage in
-                Image(uiImage: UIImage(cgImage: cgImage))
             }
             .eraseToAnyPublisher()
     }
@@ -84,31 +92,28 @@ extension ImageFilteringViewModel {
 private extension ImageFilteringViewModel {
 
     func setupSubscribers() {
-        filteredImagePublisher
+
+        filteredCGImagePublisher
             .receive(on: DispatchQueue.main)
-            .assign(to: \.filteredImage, on: self)
+            .sink(
+                receiveCompletion: { completion in
+                    switch completion {
+                    case .failure(let error):
+                        print("filteredImagePublisher error")
+                        switch error {
+                        case .cgImage(let message),
+                             .ciImage(let message),
+                             .filtering(let message):
+                            self.filteringErrorMessage = message
+                        }
+                    case .finished:
+                        print("filteredImagePublisher finished")
+                    }
+                },
+                receiveValue: {
+                    self.store.send(.filteredImages(.setFilteredOutput(image: $0)))
+                }
+            )
             .store(in: &subscriptions)
-        
-        
-//        filteredImagePublisher
-//            .receive(on: DispatchQueue.main)
-//            .sink(
-//                receiveCompletion: { completion in
-//                    switch completion {
-//                    case .failure(let error):
-//                        print("filteredImagePublisher error")
-//                        switch error {
-//                        case .cgImage(let message),
-//                             .ciImage(let message),
-//                             .filtering(let message):
-//                            self.filteringErrorMessage = message
-//                        }
-//                    case .finished:
-//                        print("filteredImagePublisher finished")
-//                    }
-//                },
-//                receiveValue: { self.filteredImage = $0 }
-//            )
-//            .store(in: &subscriptions)
     }
 }