Move macOS parts to viewModifiers

Views/SearchResults.swift

@@ -24,7 +24,7 @@ struct SearchResults: View {
     @Environment(\.managedObjectContext) private var managedObjectContext
     @EnvironmentObject private var viewModel: SearchViewModel
     @EnvironmentObject private var navigation: NavigationViewModel
-    @FocusState private var focusedSearchItem: URL?
+    @FocusState private var focusedSearchItem: URL? // macOS only
     @FetchRequest(
         sortDescriptors: [NSSortDescriptor(keyPath: \ZimFile.size, ascending: false)],
         predicate: ZimFile.Predicate.isDownloaded,
@@ -92,23 +92,26 @@ struct SearchResults: View {
                                 ArticleCell(result: result, zimFile: viewModel.zimFiles[result.zimFileID])
                             }
                             .buttonStyle(.plain)
-                            .id(result.url)
-                            .focusable()
-                            .focused($focusedSearchItem, equals: result.url)
-                            .modifier(KeyPressHandler(key: .return, action: {
-                                NotificationCenter.openURL(result.url)
-                            }))
-                            .modifier(KeyPressHandler(key: .escape, action: {
-                                $focusedSearchItem.wrappedValue = nil
-                                dismissSearch()
-                            }))
+                            .modifier(
+                                Focusable( // macOS only
+                                    $focusedSearchItem,
+                                    equals: result.url,
+                                    onReturn: {
+                                        NotificationCenter.openURL(result.url)
+                                    },
+                                    onDismiss: {
+                                        $focusedSearchItem.wrappedValue = nil
+                                        dismissSearch()
+                                    })
+                            )
                         }
                     }.padding()
                 }
                 .onReceive(self.focusedSearchItem.publisher) { focusedURL in
                     scrollReader.scrollTo(focusedURL, anchor: .center)
                 }
-                .onMoveCommand { direction in
+                .modifier(MoveCommand(perform: { direction in
+                    // macOS only
                     if let focusedSearchItem,
                        let index = viewModel.results.firstIndex(where: { $0.url == focusedSearchItem }) {
                         let nextIndex: Int
@@ -121,7 +124,7 @@ struct SearchResults: View {
                             $focusedSearchItem.wrappedValue = viewModel.results[nextIndex].url
                         }
                     }
-                }
+                }))
             }
         }
     }
@@ -160,7 +163,7 @@ struct SearchResults: View {
                 } header: { searchFilterHeader }
             }
         }
-        .focusable(false)
+        .modifier(NotFocusable()) // macOS only
     }
 
     private var recentSearchHeader: some View {

Views/ViewModifiers/Focusable.swift

@@ -0,0 +1,65 @@
+// This file is part of Kiwix for iOS & macOS.
+//
+// Kiwix is free software; you can redistribute it and/or modify it
+// under the terms of the GNU General Public License as published by
+// the Free Software Foundation; either version 3 of the License, or
+// any later version.
+//
+// Kiwix is distributed in the hope that it will be useful, but
+// WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+// General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Kiwix; If not, see https://www.gnu.org/licenses/.
+
+import SwiftUI
+
+struct NotFocusable: ViewModifier {
+    
+    func body(content: Content) -> some View {
+        #if os(macOS)
+        content.focusable(false)
+        #else
+        content
+        #endif
+    }
+}
+
+struct Focusable<Value: Hashable>: ViewModifier {
+    
+    private let value: Value
+    private let focusState: FocusState<Value>.Binding
+    private let onReturn: () -> Void
+    private let onDissmiss: () -> Void
+    
+    init(
+        _ binding: FocusState<Value>.Binding,
+        equals value: Value,
+        onReturn: @escaping () -> Void,
+        onDismiss: @escaping () -> Void
+    ) {
+        self.focusState = binding
+        self.value = value
+        self.onReturn = onReturn
+        self.onDissmiss = onDismiss
+    }
+    
+    func body(content: Content) -> some View {
+        #if os(macOS)
+        content
+            .id(value)
+            .focusable()
+            .focused(focusState, equals: value)
+            .modifier(KeyPressHandler(key: .return, action: {
+                onReturn()
+            }))
+            .modifier(KeyPressHandler(key: .escape, action: {
+                onDissmiss()
+            }))
+        #else
+        content
+        #endif
+        
+    }
+}

Views/ViewModifiers/KeyPressHandler.swift

@@ -21,15 +21,19 @@ struct KeyPressHandler: ViewModifier {
     let action: () -> Void
     
     func body(content: Content) -> some View {
+        #if os(macOS)
         if #available(macOS 14.0, *) {
-            mac14(content: content)
+            newApi(content: content)
         } else {
             content
         }
+        #else
+        content
+        #endif
     }
     
-    @available(macOS 14.0, *)
-    private func mac14(content: Content) -> some View {
+    @available(macOS 14.0, iOS 17.0, *)
+    private func newApi(content: Content) -> some View {
         content.onKeyPress(key, action: {
             Task { await MainActor.run {
                 action()

Views/ViewModifiers/MoveCommand.swift

@@ -0,0 +1,57 @@
+// This file is part of Kiwix for iOS & macOS.
+//
+// Kiwix is free software; you can redistribute it and/or modify it
+// under the terms of the GNU General Public License as published by
+// the Free Software Foundation; either version 3 of the License, or
+// any later version.
+//
+// Kiwix is distributed in the hope that it will be useful, but
+// WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+// General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Kiwix; If not, see https://www.gnu.org/licenses/.
+
+import SwiftUI
+
+enum MoveDirection: Sendable {
+    
+    case up
+    case down
+    case left
+    case right
+    
+    #if os(macOS)
+    init?(from direction: MoveCommandDirection) {
+        switch direction {
+        case .up: self = .up
+        case .down: self = .down
+        case .left: self = .left
+        case .right: self = .right
+        @unknown default: return nil
+        }
+    }
+    #endif
+}
+
+struct MoveCommand: ViewModifier {
+    
+    private let action: ((MoveDirection) -> Void)?
+    
+    init(perform action: ((MoveDirection) -> Void)?) {
+        self.action = action
+    }
+    
+    func body(content: Content) -> some View {
+        #if os(macOS)
+        content.onMoveCommand { (direction: MoveCommandDirection) in
+            if let mappedDirection = MoveDirection(from: direction) {
+                action?(mappedDirection)
+            }
+        }
+        #else
+        content
+        #endif
+    }
+}