refactor: 바인딩 구조 리팩토링

boostcampwm-2024 · Nov 19, 2024 · d78817a · d78817a
1 parent 4da102c
commit d78817a
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Showing 2 changed files with 47 additions and 23 deletions.
diff --git a/...use/MHPresentation/MHPresentation/Source/CustomAlbum/View/CustomAlbumViewController.swift b/...use/MHPresentation/MHPresentation/Source/CustomAlbum/View/CustomAlbumViewController.swift
@@ -17,7 +17,8 @@ final class CustomAlbumViewController: UIViewController {
         return collectionView
     }()
     private let viewModel: CustomAlbumViewModel
-    private var cancellables: Set<AnyCancellable> = []
+    private let input = PassthroughSubject<CustomAlbumViewModel.Input, Never>()
+    private var cancellables = Set<AnyCancellable>()
 
     // MARK: - Initializer
     init(viewModel: CustomAlbumViewModel) {
@@ -43,7 +44,7 @@ final class CustomAlbumViewController: UIViewController {
         bind()
         setup()
         configureConstraints()
-        viewModel.action(.viewDidLoad)
+        input.send(.viewDidLoad)
     }
 
     override func viewWillAppear(_ animated: Bool) {
@@ -54,15 +55,25 @@ final class CustomAlbumViewController: UIViewController {
 
     // MARK: - Binding
     private func bind() {
-        viewModel.changedAssetsOutput
-            .receive(on: DispatchQueue.main)
-            .sink { [weak self] changes in
-                self?.albumCollectionView.performBatchUpdates {
-                    if let inserted = changes.insertedIndexes, !inserted.isEmpty {
-                        self?.albumCollectionView.insertItems(at: inserted.map({ IndexPath(item: $0 + 1, section: 0) }))
-                    }
-                    if let removed = changes.removedIndexes, !removed.isEmpty {
-                        self?.albumCollectionView.deleteItems(at: removed.map({ IndexPath(item: $0 + 1, section: 0) }))
+        let output = viewModel.transform(input: input.eraseToAnyPublisher())
+
+        output.receive(on: DispatchQueue.main)
+            .sink { [weak self] event in
+                switch event {
+                case .fetchAssets:
+                    self?.albumCollectionView.reloadData()
+                case .changedAssets(let changes):
+                    self?.albumCollectionView.performBatchUpdates {
+                        if let inserted = changes.insertedIndexes, !inserted.isEmpty {
+                            self?.albumCollectionView.insertItems(
+                                at: inserted.map({ IndexPath(item: $0 + 1, section: 0) })
+                            )
+                        }
+                        if let removed = changes.removedIndexes, !removed.isEmpty {
+                            self?.albumCollectionView.deleteItems(
+                                at: removed.map({ IndexPath(item: $0 + 1, section: 0) })
+                            )
+                        }
                     }
                 }
             }
@@ -231,7 +242,7 @@ extension CustomAlbumViewController: UIImagePickerControllerDelegate, UINavigati
 extension CustomAlbumViewController: PHPhotoLibraryChangeObserver {
     nonisolated func photoLibraryDidChange(_ changeInstance: PHChange) {
         Task { @MainActor in
-            viewModel.action(.photoDidChanged(changeInstance))
+            input.send(.photoDidChanged(changeInstance))
         }
     }
 }
diff --git a/...use/MHPresentation/MHPresentation/Source/CustomAlbum/ViewModel/CustomAlbumViewModel.swift b/...use/MHPresentation/MHPresentation/Source/CustomAlbum/ViewModel/CustomAlbumViewModel.swift
@@ -2,30 +2,43 @@ import MHFoundation
 import Photos
 import Combine
 
-final class CustomAlbumViewModel {
+final class CustomAlbumViewModel: ViewModelType {
     enum Input {
         case viewDidLoad
         case photoDidChanged(_ changeInstance: PHChange)
     }
-    // MARK: - Properties
-    @Published private(set) var photoAsset: PHFetchResult<PHAsset>?
-    let changedAssetsOutput = PassthroughSubject<PHFetchResultChangeDetails<PHAsset>, Never>()
 
-    func action(_ input: CustomAlbumViewModel.Input) {
-        switch input {
-        case .viewDidLoad:
-            fetchPhotoAssets()
-        case .photoDidChanged(let changeInstance):
-            updatePhotoAssets(changeInstance)
+    enum Output {
+        case fetchAssets
+        case changedAssets(_ changes: PHFetchResultChangeDetails<PHAsset>)
+    }
+
+    private let output = PassthroughSubject<Output, Never>()
+    private var cancellables = Set<AnyCancellable>()
+    private(set) var photoAsset: PHFetchResult<PHAsset>?
+
+    func transform(input: AnyPublisher<Input, Never>) -> AnyPublisher<Output, Never> {
+        input.sink { [weak self] events in
+            switch events {
+            case .viewDidLoad:
+                self?.fetchPhotoAssets()
+            case .photoDidChanged(let changeInstance):
+                self?.updatePhotoAssets(changeInstance)
+            }
         }
+        .store(in: &cancellables)
+
+        return output.eraseToAnyPublisher()
     }
 
+
     private func fetchPhotoAssets() {
         let fetchOptions = PHFetchOptions()
         fetchOptions.predicate = NSPredicate(format: "mediaType = %d", PHAssetMediaType.image.rawValue)
         fetchOptions.sortDescriptors = [NSSortDescriptor(key: "creationDate", ascending: false)]
 
         photoAsset = PHAsset.fetchAssets(with: fetchOptions)
+        output.send(.fetchAssets)
     }
 
     private func updatePhotoAssets(_ changeInstance: PHChange) {
@@ -35,7 +48,7 @@ final class CustomAlbumViewModel {
         self.photoAsset = changes.fetchResultAfterChanges
 
         if changes.hasIncrementalChanges {
-            changedAssetsOutput.send(changes)
+            output.send(.changedAssets(changes))
         }
     }
 }