Merge pull request #17 from rock-n-code/feature/download-file

Feature: Download file

Modules/Sources/Browse/Resources/en.lproj/Localizable.strings

@@ -46,12 +46,16 @@
 "delete_item.system_alert.message" = "An unexpected error occurred while trying to delete the indicated folder from the current folder.\n\nPlease check your Internet connection and try this operation at a later time.";
 "delete_item.system_alert.button.cancel" = "Understood";
 
-// BrowseView
+// BrowseToolbar
 
 "browse.toolbar_item.menu.add_actions.text" = "Add file and/or folder";
 "browse.toolbar_item.button.add_folder.text" = "Create a new folder";
 "browse.toolbar_item.button.add_file.text" = "Upload a file";
 "browse.toolbar_item.button.show_profile.text" = "Show profile";
 
+// DocumentToolbar
+
+"document.toolbar_item.button.download_file.text" = "Download this file";
+
 "browse.swipe_action.delete_item.text" = "Delete item";
 "browse.swipe_action.download_item.text" = "Download item";

Modules/Sources/Browse/UI/Components/SaveDocumentPicker.swift

@@ -0,0 +1,120 @@
+//
+//  SaveDocumentPicker.swift
+//  Browse
+//
+//  Created by Javier Cicchelli on 17/12/2022.
+//  Copyright © 2022 Röck+Cöde. All rights reserved.
+//
+
+import Foundation
+import SwiftUI
+import UIKit
+
+struct SaveDocumentPicker: UIViewControllerRepresentable {
+
+    // MARK: Type aliases
+
+    typealias DownloadedClosure = (NSError?) -> Void
+    typealias CancelledClosure = () -> Void
+
+    // MARK: Properties
+
+    private let fileName: String
+    private let fileData: Data
+    private let downloaded: DownloadedClosure
+    private let cancelled: CancelledClosure?
+
+    // MARK: Initialisers
+
+    init(
+        fileName: String,
+        fileData: Data,
+        downloaded: @escaping DownloadedClosure,
+        cancelled: CancelledClosure? = nil
+    ) {
+        self.fileName = fileName
+        self.fileData = fileData
+        self.downloaded = downloaded
+        self.cancelled = cancelled
+    }
+
+    // MARK: Functions
+
+    func makeUIViewController(context: Context) -> UIDocumentPickerViewController {
+        let controller = UIDocumentPickerViewController(
+            forOpeningContentTypes: [.folder]
+        )
+
+        controller.allowsMultipleSelection = false
+        controller.shouldShowFileExtensions = false
+        controller.delegate = context.coordinator
+
+        return controller
+    }
+
+    func updateUIViewController(
+        _ uiViewController: UIDocumentPickerViewController,
+        context: Context
+    ) { }
+
+    func makeCoordinator() -> Coordinator {
+        .init(self)
+    }
+}
+
+// MARK: - Coordinators
+
+extension SaveDocumentPicker {
+    class Coordinator: NSObject, UIDocumentPickerDelegate {
+
+        // MARK: Properties
+
+        private let parent: SaveDocumentPicker
+        private let fileCoordinator: NSFileCoordinator = .init()
+        private let fileManager: FileManager = .default
+
+        // MARK: Initialisers
+
+        init(_ parent: SaveDocumentPicker) {
+            self.parent = parent
+        }
+
+        // MARK: UIDocumentPickerDelegate
+
+        func documentPicker(
+            _ controller: UIDocumentPickerViewController,
+            didPickDocumentsAt urls: [URL]
+        ) {
+            guard
+                let url = urls.first,
+                url.startAccessingSecurityScopedResource()
+            else {
+                // TODO: Handle this error appropriately.
+                return
+            }
+            
+            var error: NSError?
+            
+            fileCoordinator.coordinate(
+                writingItemAt: url,
+                error: &error
+            ) { url in
+                fileManager.createFile(
+                    atPath: url.appendingPathComponent(parent.fileName).relativePath,
+                    contents: parent.fileData
+                )
+            }
+            
+            url.stopAccessingSecurityScopedResource()
+            
+            parent.downloaded(error)
+        }
+
+        func documentPickerWasCancelled(_ controller: UIDocumentPickerViewController) {
+            controller.dismiss(animated: true) { [weak self] in
+                self?.parent.cancelled?()
+            }
+        }
+
+    }
+}

Modules/Sources/Browse/UI/Components/SelectDocumentPicker.swift

@@ -1,5 +1,5 @@
 //
-//  DocumentPicker.swift
+//  SelectDocumentPicker.swift
 //  Browse
 //
 //  Created by Javier Cicchelli on 17/12/2022.
@@ -10,7 +10,7 @@ import Foundation
 import SwiftUI
 import UIKit
 
-struct DocumentPicker: UIViewControllerRepresentable {
+struct SelectDocumentPicker: UIViewControllerRepresentable {
     
     // MARK: Type aliases
     
@@ -55,20 +55,21 @@ struct DocumentPicker: UIViewControllerRepresentable {
     func makeCoordinator() -> Coordinator {
         .init(self)
     }
+
 }
 
 // MARK: - Coordinators
 
-extension DocumentPicker {
+extension SelectDocumentPicker {
     class Coordinator: NSObject, UIDocumentPickerDelegate {
         
         // MARK: Properties
         
-        private var parent: DocumentPicker
+        private var parent: SelectDocumentPicker
         
         // MARK: Initialisers
         
-        init(_ parent: DocumentPicker) {
+        init(_ parent: SelectDocumentPicker) {
             self.parent = parent
         }
         

Modules/Sources/Browse/UI/Toolbars/BrowseToolbar.swift

@@ -28,8 +28,7 @@ struct BrowseToolbar: ToolbarContent {
                     Label {
                         Text(
                             "browse.toolbar_item.button.add_folder.text",
-                            bundle: .module,
+                            bundle: .module
-                            comment: "Add folder button text."
                         )
                     } icon: {
                         Image.newFolder
@@ -42,8 +41,7 @@ struct BrowseToolbar: ToolbarContent {
                     Label {
                         Text(
                             "browse.toolbar_item.button.add_file.text",
-                            bundle: .module,
+                            bundle: .module
-                            comment: "Add file button text."
                         )
                     } icon: {
                         Image.newFile
@@ -53,8 +51,7 @@ struct BrowseToolbar: ToolbarContent {
                 Label {
                     Text(
                         "browse.toolbar_item.menu.add_actions.text",
-                        bundle: .module,
+                        bundle: .module
-                        comment: "Add actions menu text."
                     )
                 } icon: {
                     Image.add
@@ -72,8 +69,7 @@ struct BrowseToolbar: ToolbarContent {
                 Label {
                     Text(
                         "browse.toolbar_item.button.show_profile.text",
-                        bundle: .module,
+                        bundle: .module
-                        comment: "Show profile button text."
                     )
                 } icon: {
                     Image.profile

Modules/Sources/Browse/UI/Toolbars/DocumentToolbar.swift

@@ -0,0 +1,42 @@
+//
+//  DocumentToolbar.swift
+//  Browse
+//
+//  Created by Javier Cicchelli on 18/12/2022.
+//  Copyright © 2022 Röck+Cöde. All rights reserved.
+//
+
+import DataModels
+import SwiftUI
+
+struct DocumentToolbar: ToolbarContent {
+    
+    // MARK: Properties
+    
+    let disabled: Bool
+    let downloadFile: ActionClosure
+    
+    // MARK: Body
+    
+    var body: some ToolbarContent {
+        ToolbarItem(placement: .primaryAction) {
+            Button {
+                downloadFile()
+            } label: {
+                Label {
+                    Text(
+                        "document.toolbar_item.button.download_file.text",
+                        bundle: .module
+                    )
+                } icon: {
+                    Image.download
+                        .resizable()
+                        .scaledToFit()
+                        .frame(width: 24, height: 24)
+                }
+            }
+            .disabled(disabled)
+        }
+    }
+
+}

Modules/Sources/Browse/UI/Views/BrowseView.swift

@@ -23,7 +23,7 @@ public struct BrowseView: View {
     @State private var stack: Stack?
     @State private var itemToDelete: (any FileSystemItem)?
     @State private var showCreateFolder: Bool = false
-    @State private var showUploadFile: Bool = false
+    @State private var showSheet: SheetView?
     
     // MARK: Properties
     
@@ -56,14 +56,24 @@ public struct BrowseView: View {
                         showCreateFolder = true
                     },
                     uploadFile: {
-                        showUploadFile = true
+                        showSheet = .upload(id: folder.id)
                     },
                     showProfile: showProfile
                 )
             }
-            .sheet(isPresented: $showUploadFile) {
+            .sheet(item: $showSheet) { sheet in
-                UploadView(id: folder.id) {
+                switch sheet {
-                    Task { await loadItems() }
+                case let .upload(id):
+                    UploadView(id: id) {
+                        Task { await loadItems() }
+                    }
+                case let .download(id, name):
+                    DownloadView(
+                        id: id,
+                        name: name
+                    ) {
+                        Task { await loadItems() }
+                    }
                 }
             }
             .createFolder(
@@ -118,7 +128,7 @@ private extension BrowseView {
             MessageView(
                 type: .empty,
                 action: {
-                    showUploadFile = true
+                    showSheet = .upload(id: folder.id)
                 }
             )
         case .error:
@@ -162,7 +172,10 @@ private extension BrowseView {
             DocumentItem(item: item) {
                 stack = .open(document)
             } download: {
-                // TODO: download the item id from the backend.
+                showSheet = .download(
+                    id: document.id,
+                    name: document.name
+                )
             } delete: {
                 itemToDelete = item
             }
@@ -211,6 +224,17 @@ private extension BrowseView {
     }
 }
 
+// MARK: - Enumerations
+
+private extension BrowseView {
+    enum SheetView: Identifiable {
+        case upload(id: String)
+        case download(id: String, name: String)
+        
+        var id: String { UUID().uuidString }
+    }
+}
+
 // MARK: - Previews
 
 struct BrowseView_Previews: PreviewProvider {

Modules/Sources/Browse/UI/Views/DocumentView.swift

@@ -24,6 +24,7 @@ struct DocumentView: View {
     
     @State private var status: ViewStatus = .loading
     @State private var loadedData: Data?
+    @State private var showDownloadFile: Bool = false
     
     private let getData = GetDataUseCase()
     
@@ -38,6 +39,20 @@ struct DocumentView: View {
         content
             .navigationTitle(document.name)
             .navigationBarTitleDisplayMode(.inline)
+            .toolbar {
+                DocumentToolbar(disabled: isToolbarDisabled) {
+                    showDownloadFile = true
+                }
+            }
+            .sheet(isPresented: $showDownloadFile) {
+                DownloadView(
+                    id: document.id,
+                    name: document.name,
+                    data: loadedData
+                ) {
+                    // downloaded closure.
+                }
+            }
             .task {
                 await loadDataIfPossible()
             }
@@ -48,6 +63,8 @@ struct DocumentView: View {
 // MARK: - UI
 
 private extension DocumentView {
+    var isToolbarDisabled: Bool { loadedData == nil }
+    
     @ViewBuilder var content: some View {
         switch status {
         case .noCredentials:

Modules/Sources/Browse/UI/Views/DownloadView.swift

@@ -0,0 +1,104 @@
+//
+//  DownloadView.swift
+//  Browse
+//
+//  Created by Javier Cicchelli on 17/12/2022.
+//  Copyright © 2022 Röck+Cöde. All rights reserved.
+//
+
+import DataModels
+import Foundation
+import KeychainStorage
+import SwiftUI
+
+struct DownloadView: View {
+    
+    // MARK: Storages
+    
+    @KeychainStorage(key: .KeychainStorage.account) private var account: Account?
+    
+    // MARK: States
+    
+    @State private var data: Data?
+    
+    // MARK: Properties
+    
+    private let id: String
+    private let name: String
+    private let downloaded: ActionClosure
+    
+    private let getData: GetDataUseCase = .init()
+    
+    // MARK: Initialisers
+    
+    init(
+        id: String,
+        name: String,
+        data: Data? = nil,
+        downloaded: @escaping ActionClosure
+    ) {
+        self.id = id
+        self.name = name
+        self.downloaded = downloaded
+        
+        self._data = .init(initialValue: data)
+    }
+    
+    // MARK: Body
+    
+    var body: some View {
+        if let data {
+            SaveDocumentPicker(
+                fileName: name,
+                fileData: data
+            ) { error in
+                guard error == nil else {
+                    // TODO: Handle this error case.
+                    return
+                }
+                
+                downloaded()
+            }
+        } else {
+            LoadingView()
+                .task {
+                    await loadData()
+                }
+        }
+    }
+
+}
+
+// MARK: - Helpers
+
+private extension DownloadView {
+    func loadData() async {
+        guard let account else {
+            // TODO: Handle this error case.
+            return
+        }
+        
+        do {
+            data = try await getData(
+                id: id,
+                username: account.username,
+                password: account.password
+            )
+        } catch {
+            // TODO: Handle this error case.
+        }
+    }
+}
+
+// MARK: - Previews
+
+struct DownloadView_Previews: PreviewProvider {
+    static var previews: some View {
+        DownloadView(
+            id: "1234567890",
+            name: "some-name.txt"
+        ) {
+            // Downloaded closure.
+        }
+    }
+}

Modules/Sources/Browse/UI/Views/UploadView.swift

@@ -32,7 +32,7 @@ struct UploadView: View {
     // MARK: Body
     
     var body: some View {
-        DocumentPicker { urls in
+        SelectDocumentPicker { urls in
             Task { await addFile(from: urls) }
         }
     }