feat: add save photo action for image preview scene

Mastodon.xcodeproj/project.pbxproj

@@ -380,6 +380,7 @@
 		DB9E0D6F25EE008500CFDD76 /* UIInterpolatingMotionEffect.swift in Sources */ = {isa = PBXBuildFile; fileRef = DB9E0D6E25EE008500CFDD76 /* UIInterpolatingMotionEffect.swift */; };
 		DBA0A10925FB3C2B0079C110 /* RoundedEdgesButton.swift in Sources */ = {isa = PBXBuildFile; fileRef = DBA0A10825FB3C2B0079C110 /* RoundedEdgesButton.swift */; };
 		DBA0A11325FB3FC10079C110 /* ComposeToolbarView.swift in Sources */ = {isa = PBXBuildFile; fileRef = DBA0A11225FB3FC10079C110 /* ComposeToolbarView.swift */; };
+		DBA5E7A3263AD0A3004598BB /* PhotoLibraryService.swift in Sources */ = {isa = PBXBuildFile; fileRef = DBA5E7A2263AD0A3004598BB /* PhotoLibraryService.swift */; };
 		DBABE3EC25ECAC4B00879EE5 /* WelcomeIllustrationView.swift in Sources */ = {isa = PBXBuildFile; fileRef = DBABE3EB25ECAC4B00879EE5 /* WelcomeIllustrationView.swift */; };
 		DBAE3F682615DD60004B8251 /* UserProvider.swift in Sources */ = {isa = PBXBuildFile; fileRef = DBAE3F672615DD60004B8251 /* UserProvider.swift */; };
 		DBAE3F822615DDA3004B8251 /* ProfileViewController+UserProvider.swift in Sources */ = {isa = PBXBuildFile; fileRef = DBAE3F812615DDA3004B8251 /* ProfileViewController+UserProvider.swift */; };
@@ -935,6 +936,7 @@
 		DB9E0D6E25EE008500CFDD76 /* UIInterpolatingMotionEffect.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = UIInterpolatingMotionEffect.swift; sourceTree = "<group>"; };
 		DBA0A10825FB3C2B0079C110 /* RoundedEdgesButton.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = RoundedEdgesButton.swift; sourceTree = "<group>"; };
 		DBA0A11225FB3FC10079C110 /* ComposeToolbarView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ComposeToolbarView.swift; sourceTree = "<group>"; };
+		DBA5E7A2263AD0A3004598BB /* PhotoLibraryService.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PhotoLibraryService.swift; sourceTree = "<group>"; };
 		DBABE3EB25ECAC4B00879EE5 /* WelcomeIllustrationView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = WelcomeIllustrationView.swift; sourceTree = "<group>"; };
 		DBAE3F672615DD60004B8251 /* UserProvider.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = UserProvider.swift; sourceTree = "<group>"; };
 		DBAE3F812615DDA3004B8251 /* ProfileViewController+UserProvider.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "ProfileViewController+UserProvider.swift"; sourceTree = "<group>"; };
@@ -1289,6 +1291,7 @@
 				DBC7A67B260DFADE00E57475 /* StatusPublishService.swift */,
 				DB4924E126312AB200E9DB22 /* NotificationService.swift */,
 				DB6D9F6226357848008423CD /* SettingService.swift */,
+				DBA5E7A2263AD0A3004598BB /* PhotoLibraryService.swift */,
 			);
 			path = Service;
 			sourceTree = "<group>";
@@ -2864,6 +2867,7 @@
 				2D8434F525FF465D00EECE90 /* HomeTimelineNavigationBarTitleViewModel.swift in Sources */,
 				DB938F0F2624119800E5B6C1 /* ThreadViewModel+LoadThreadState.swift in Sources */,
 				DB6180F226391CF40018D199 /* MediaPreviewImageViewModel.swift in Sources */,
+				DBA5E7A3263AD0A3004598BB /* PhotoLibraryService.swift in Sources */,
 				5DDDF1932617442700311060 /* Mastodon+Entity+Account.swift in Sources */,
 				DBAE3F882615DDF4004B8251 /* UserProviderFacade.swift in Sources */,
 				2D607AD826242FC500B70763 /* NotificationViewModel.swift in Sources */,

Mastodon.xcodeproj/xcuserdata/mainasuk.xcuserdatad/xcschemes/xcschememanagement.plist

@@ -12,7 +12,7 @@
 		<key>CoreDataStack.xcscheme_^#shared#^_</key>
 		<dict>
 			<key>orderHint</key>
-			<integer>14</integer>
+			<integer>18</integer>
 		</dict>
 		<key>Mastodon - RTL.xcscheme_^#shared#^_</key>
 		<dict>
@@ -32,7 +32,7 @@
 		<key>NotificationService.xcscheme_^#shared#^_</key>
 		<dict>
 			<key>orderHint</key>
-			<integer>15</integer>
+			<integer>17</integer>
 		</dict>
 	</dict>
 	<key>SuppressBuildableAutocreation</key>

Mastodon/Scene/MediaPreview/MediaPreviewViewController.swift

@@ -191,11 +191,38 @@ extension MediaPreviewViewController: PageboyViewControllerDelegate {
 extension MediaPreviewViewController: MediaPreviewImageViewControllerDelegate {
     
     func mediaPreviewImageViewController(_ viewController: MediaPreviewImageViewController, tapGestureRecognizerDidTrigger tapGestureRecognizer: UITapGestureRecognizer) {
-        
+        // do nothing
     }
     
     func mediaPreviewImageViewController(_ viewController: MediaPreviewImageViewController, longPressGestureRecognizerDidTrigger longPressGestureRecognizer: UILongPressGestureRecognizer) {
-        // delegate?.mediaPreviewViewController(self, longPressGestureRecognizerTriggered: longPressGestureRecognizer)
+        // do nothing
+    }
+    
+    func mediaPreviewImageViewController(_ viewController: MediaPreviewImageViewController, contextMenuActionPerform action: MediaPreviewImageViewController.ContextMenuAction) {
+        switch action {
+        case .savePhoto:
+            switch viewController.viewModel.item {
+            case .status(let meta):
+                context.photoLibraryService.saveImage(url: meta.url).sink { _ in
+                    // do nothing
+                } receiveValue: { _ in
+                    // do nothing
+                }
+                .store(in: &context.disposeBag)
+            case .local(let meta):
+                context.photoLibraryService.save(image: meta.image, withNotificationFeedback: true)
+            }
+        case .share:
+            let applicationActivities: [UIActivity] = [
+                SafariActivity(sceneCoordinator: self.coordinator)
+            ]
+            let activityViewController = UIActivityViewController(
+                activityItems: viewController.viewModel.item.activityItems,
+                applicationActivities: applicationActivities
+            )
+            activityViewController.popoverPresentationController?.sourceView = viewController.previewImageView.imageView
+            self.present(activityViewController, animated: true, completion: nil)
+        }
     }
     
 }

Mastodon/Scene/MediaPreview/Paging/Image/MediaPreviewImageViewController.swift

@@ -9,9 +9,10 @@ import os.log
 import UIKit
 import Combine
 
-protocol MediaPreviewImageViewControllerDelegate: class {
+protocol MediaPreviewImageViewControllerDelegate: AnyObject {
     func mediaPreviewImageViewController(_ viewController: MediaPreviewImageViewController, tapGestureRecognizerDidTrigger tapGestureRecognizer: UITapGestureRecognizer)
     func mediaPreviewImageViewController(_ viewController: MediaPreviewImageViewController, longPressGestureRecognizerDidTrigger longPressGestureRecognizer: UILongPressGestureRecognizer)
+    func mediaPreviewImageViewController(_ viewController: MediaPreviewImageViewController, contextMenuActionPerform action: MediaPreviewImageViewController.ContextMenuAction)
 }
 
 final class MediaPreviewImageViewController: UIViewController {
@@ -63,6 +64,9 @@ extension MediaPreviewImageViewController {
         previewImageView.addGestureRecognizer(tapGestureRecognizer)
         previewImageView.addGestureRecognizer(longPressGestureRecognizer)
         
+        let previewImageViewContextMenuInteraction = UIContextMenuInteraction(delegate: self)
+        previewImageView.addInteraction(previewImageViewContextMenuInteraction)
+        
         switch viewModel.item {
         case .status(let meta):
 //            progressBarView.isHidden = meta.thumbnail != nil
@@ -113,3 +117,50 @@ extension MediaPreviewImageViewController {
     }
     
 }
+
+// MARK: - UIContextMenuInteractionDelegate
+extension MediaPreviewImageViewController: UIContextMenuInteractionDelegate {
+    func contextMenuInteraction(_ interaction: UIContextMenuInteraction, configurationForMenuAtLocation location: CGPoint) -> UIContextMenuConfiguration? {
+        os_log(.info, log: .debug, "%{public}s[%{public}ld], %{public}s", ((#file as NSString).lastPathComponent), #line, #function)
+        
+        let previewProvider: UIContextMenuContentPreviewProvider = { () -> UIViewController? in
+            return nil
+        }
+        
+        let saveAction = UIAction(
+            title: L10n.Common.Controls.Actions.savePhoto, image: UIImage(systemName: "square.and.arrow.down")!, identifier: nil, discoverabilityTitle: nil, attributes: [], state: .off) { [weak self] _ in
+            os_log(.info, log: .debug, "%{public}s[%{public}ld], %{public}s: save photo", ((#file as NSString).lastPathComponent), #line, #function)
+            guard let self = self else { return }
+            self.delegate?.mediaPreviewImageViewController(self, contextMenuActionPerform: .savePhoto)
+        }
+        
+        let shareAction = UIAction(
+            title: L10n.Common.Controls.Actions.share, image: UIImage(systemName: "square.and.arrow.up")!, identifier: nil, discoverabilityTitle: nil, attributes: [], state: .off) { [weak self] _ in
+            os_log(.info, log: .debug, "%{public}s[%{public}ld], %{public}s: share", ((#file as NSString).lastPathComponent), #line, #function)
+            guard let self = self else { return }
+            self.delegate?.mediaPreviewImageViewController(self, contextMenuActionPerform: .share)
+        }
+        
+        let actionProvider: UIContextMenuActionProvider = { elements -> UIMenu?  in
+            return UIMenu(title: "", image: nil, identifier: nil, options: [], children: [
+                saveAction,
+                shareAction
+            ])
+        }
+        
+        return UIContextMenuConfiguration(identifier: nil, previewProvider: previewProvider, actionProvider: actionProvider)
+    }
+    
+    func contextMenuInteraction(_ interaction: UIContextMenuInteraction, previewForHighlightingMenuWithConfiguration configuration: UIContextMenuConfiguration) -> UITargetedPreview? {
+        // set preview view
+        return UITargetedPreview(view: previewImageView.imageView)
+    }
+
+}
+
+extension MediaPreviewImageViewController {
+    enum ContextMenuAction {
+        case savePhoto
+        case share
+    }
+}

Mastodon/Scene/MediaPreview/Paging/Image/MediaPreviewImageViewModel.swift

@@ -27,6 +27,19 @@ extension MediaPreviewImageViewModel {
     enum ImagePreviewItem {
         case status(RemoteImagePreviewMeta)
         case local(LocalImagePreviewMeta)
+        
+        var activityItems: [Any] {
+            var items: [Any] = []
+            
+            switch self {
+            case .status(let meta):
+                items.append(meta.url)
+            case .local(let meta):
+                items.append(meta.image)
+            }
+            
+            return items
+        }
     }
     
     struct RemoteImagePreviewMeta {

Mastodon/Service/PhotoLibraryService.swift

@@ -0,0 +1,69 @@
+//
+//  PhotoLibraryService.swift
+//  Mastodon
+//
+//  Created by MainasuK Cirno on 2021-4-29.
+//
+
+import os.log
+import UIKit
+import Combine
+import AlamofireImage
+
+final class PhotoLibraryService: NSObject {
+
+}
+
+extension PhotoLibraryService {
+    
+    func saveImage(url: URL) -> AnyPublisher<UIImage, Error> {
+        let impactFeedbackGenerator = UIImpactFeedbackGenerator(style: .light)
+        let notificationFeedbackGenerator = UINotificationFeedbackGenerator()
+        
+        return Future<UIImage, Error> { promise in
+            ImageDownloader.default.download(URLRequest(url: url), completion: { [weak self] response in
+                guard let self = self else { return }
+                switch response.result {
+                case .failure(let error):
+                    os_log(.info, log: .debug, "%{public}s[%{public}ld], %{public}s: download image %s fail: %s", ((#file as NSString).lastPathComponent), #line, #function, url.debugDescription, error.localizedDescription)
+                    promise(.failure(error))
+                case .success(let image):
+                    os_log(.info, log: .debug, "%{public}s[%{public}ld], %{public}s: download image %s success", ((#file as NSString).lastPathComponent), #line, #function, url.debugDescription)
+                    self.save(image: image)
+                    promise(.success(image))
+                }
+            })
+        }
+        .handleEvents(receiveSubscription: { _ in
+            impactFeedbackGenerator.impactOccurred()
+        }, receiveCompletion: { completion in
+            switch completion {
+            case .failure:
+                notificationFeedbackGenerator.notificationOccurred(.error)
+            case .finished:
+                notificationFeedbackGenerator.notificationOccurred(.success)
+            }
+        })
+        .eraseToAnyPublisher()
+    }
+    
+    func save(image: UIImage, withNotificationFeedback: Bool = false) {
+        UIImageWriteToSavedPhotosAlbum(
+            image,
+            self,
+            #selector(PhotoLibraryService.image(_:didFinishSavingWithError:contextInfo:)),
+            nil
+        )
+        
+        // assert no error
+        if withNotificationFeedback {
+            let notificationFeedbackGenerator = UINotificationFeedbackGenerator()
+            notificationFeedbackGenerator.notificationOccurred(.success)
+        }
+    }
+    
+    @objc private func image(_ image: UIImage, didFinishSavingWithError error: Error?, contextInfo: UnsafeRawPointer) {
+        // TODO: notify banner
+    }
+    
+}

Mastodon/State/AppContext.swift

@@ -30,6 +30,7 @@ class AppContext: ObservableObject {
     let statusPublishService = StatusPublishService()
     let notificationService: NotificationService
     let settingService: SettingService
+    let photoLibraryService = PhotoLibraryService()
 
     let documentStore: DocumentStore
     private var documentStoreSubscription: AnyCancellable!