Add feature to disable VM screenshots

VirtualCore/Source/Models/VBVirtualMachine.swift

@@ -19,6 +19,9 @@ public struct VBVirtualMachine: Identifiable, VBStorageDeviceContainer {
         public var backgroundHash: BlurHashToken = .virtualBuddyBackground
         /// If this VM was imported from some other app, contains the name of the ``VMImporter`` that was used.
         public var importedFromAppName: String? = nil
+        /// Controls whether screenshots and thumbnails are automatically generated for this VM
+        @DecodableDefault.True
+        public var screenshotGenerationEnabled: Bool = true
 
         /// The original remote URL that was specified for downloading the restore image (if downloaded from a remote source).
         public private(set) var remoteInstallImageURL: URL? = nil

VirtualCore/Source/Virtualization/VMController.swift

@@ -373,6 +373,12 @@ public final class VMController: ObservableObject {
     }
 
     public func storeScreenshot(with data: Data) {
+        // Skip storing if screenshot generation is disabled for this VM
+        guard virtualMachineModel.metadata.screenshotGenerationEnabled else {
+            logger.debug("Screenshot generation disabled for VM \(virtualMachineModel.name), skipping screenshot storage")
+            return
+        }
+
         do {
             try virtualMachineModel.write(data, forMetadataFileNamed: VBVirtualMachine.screenshotFileName)
             try virtualMachineModel.invalidateThumbnail()            

VirtualCore/Source/Virtualization/VMInstance.swift

@@ -226,6 +226,12 @@ public final class VMInstance: NSObject, ObservableObject {
         let task = Task {
             do {
                 for await message in try await wormhole.desktopPictureMessages(from: virtualMachineModel.wormholeID) {
+                    // Skip processing if screenshot generation is disabled for this VM
+                    guard virtualMachineModel.metadata.screenshotGenerationEnabled else {
+                        logger.debug("Screenshot generation disabled for VM \(virtualMachineModel.name), skipping desktop picture message")
+                        continue
+                    }
+
                     do {
                         let fileURL = virtualMachineModel.metadataFileURL(VBVirtualMachine.thumbnailFileName)
 

VirtualUI/Source/Session/Components/VMSnapshotHoverOverlay.swift

@@ -0,0 +1,216 @@
+//
+//  VMSnapshotHoverOverlay.swift
+//  VirtualUI
+//
+//  Created for VirtualBuddy VM snapshot hover functionality.
+//
+
+import SwiftUI
+import VirtualCore
+import AppKit
+import UniformTypeIdentifiers
+
+struct VMSnapshotHoverOverlay: View {
+    @EnvironmentObject private var controller: VMController
+    @State private var isHovered = false
+
+    var body: some View {
+        GeometryReader { geometry in
+            ZStack {
+                // Invisible full coverage area for hover detection
+                Rectangle()
+                    .fill(Color.clear)
+                    .contentShape(Rectangle())
+
+                if isHovered {
+                    // Semi-transparent overlay
+                    Rectangle()
+                        .fill(Color.black.opacity(0.4))
+                        .transition(.opacity)
+
+                    // Button container
+                    VStack(spacing: 16) {
+                        Spacer()
+
+                        HStack(spacing: 16) {
+                            // Save Image button
+                            Button {
+                                saveScreenshotToHost()
+                            } label: {
+                                HStack(spacing: 8) {
+                                    Image(systemName: "square.and.arrow.down")
+                                    Text("Save Image")
+                                }
+                                .font(.system(size: 14, weight: .medium))
+                                .padding(.horizontal, 16)
+                                .padding(.vertical, 8)
+                            }
+                            .buttonStyle(OverlayButtonStyle())
+
+                            // Disable Preview button
+                            Button {
+                                toggleScreenshotGeneration()
+                            } label: {
+                                HStack(spacing: 8) {
+                                    Image(systemName: controller.virtualMachineModel.metadata.screenshotGenerationEnabled ? "eye.slash" : "eye")
+                                    Text(controller.virtualMachineModel.metadata.screenshotGenerationEnabled ? "Disable Previews" : "Enable Previews")
+                                }
+                                .font(.system(size: 14, weight: .medium))
+                                .padding(.horizontal, 16)
+                                .padding(.vertical, 8)
+                            }
+                            .buttonStyle(OverlayButtonStyle())
+                        }
+
+                        Spacer()
+                    }
+                }
+            }
+        }
+        .onHover { hovering in
+            withAnimation(.easeInOut(duration: 0.2)) {
+                isHovered = hovering
+            }
+        }
+    }
+
+    private func saveScreenshotToHost() {
+        guard let screenshot = controller.virtualMachineModel.screenshot else {
+            NSAlert.runInformationAlert(
+                title: "No Screenshot Available",
+                message: "There is no screenshot available for this virtual machine."
+            )
+            return
+        }
+
+        let savePanel = NSSavePanel()
+        savePanel.title = "Save VM Screenshot"
+        savePanel.nameFieldStringValue = "\(controller.virtualMachineModel.name) Screenshot"
+        savePanel.allowedContentTypes = [.png, .jpeg, .heic]
+        savePanel.canCreateDirectories = true
+
+        savePanel.begin { response in
+            guard response == .OK, let url = savePanel.url else { return }
+
+            // Convert to the appropriate format based on file extension
+            let fileExtension = url.pathExtension.lowercased()
+            let success: Bool
+
+            switch fileExtension {
+            case "png":
+                success = screenshot.pngWrite(to: url)
+            case "jpg", "jpeg":
+                success = screenshot.jpegWrite(to: url, compressionFactor: 0.9)
+            case "heic":
+                success = (try? screenshot.vb_encodeHEIC(to: url)) != nil
+            default:
+                // Default to PNG
+                success = screenshot.pngWrite(to: url.appendingPathExtension("png"))
+            }
+
+            if !success {
+                NSAlert.runErrorAlert(
+                    title: "Save Failed",
+                    message: "Failed to save the screenshot to \(url.path)."
+                )
+            }
+        }
+    }
+
+    private func toggleScreenshotGeneration() {
+        let currentlyEnabled = controller.virtualMachineModel.metadata.screenshotGenerationEnabled
+        controller.virtualMachineModel.metadata.screenshotGenerationEnabled = !currentlyEnabled
+
+        // Force save the metadata
+        do {
+            try controller.virtualMachineModel.saveMetadata()
+        } catch {
+            NSAlert.runErrorAlert(
+                title: "Settings Save Failed",
+                message: "Failed to save the screenshot generation setting: \(error.localizedDescription)"
+            )
+            // Revert the change
+            controller.virtualMachineModel.metadata.screenshotGenerationEnabled = currentlyEnabled
+        }
+    }
+}
+
+// Custom button style for overlay buttons
+private struct OverlayButtonStyle: ButtonStyle {
+    func makeBody(configuration: Configuration) -> some View {
+        configuration.label
+            .background(
+                RoundedRectangle(cornerRadius: 8)
+                    .fill(Material.thick)
+                    .shadow(color: .black.opacity(0.3), radius: 4, x: 0, y: 2)
+            )
+            .foregroundColor(.primary)
+            .scaleEffect(configuration.isPressed ? 0.95 : 1.0)
+            .animation(.easeInOut(duration: 0.1), value: configuration.isPressed)
+    }
+}
+
+// Extensions for NSImage saving
+private extension NSImage {
+    func pngWrite(to url: URL) -> Bool {
+        guard let tiffRepresentation = tiffRepresentation,
+              let bitmapImage = NSBitmapImageRep(data: tiffRepresentation),
+              let pngData = bitmapImage.representation(using: .png, properties: [:]) else {
+            return false
+        }
+
+        do {
+            try pngData.write(to: url)
+            return true
+        } catch {
+            return false
+        }
+    }
+
+    func jpegWrite(to url: URL, compressionFactor: CGFloat = 0.9) -> Bool {
+        guard let tiffRepresentation = tiffRepresentation,
+              let bitmapImage = NSBitmapImageRep(data: tiffRepresentation),
+              let jpegData = bitmapImage.representation(using: .jpeg, properties: [.compressionFactor: compressionFactor]) else {
+            return false
+        }
+
+        do {
+            try jpegData.write(to: url)
+            return true
+        } catch {
+            return false
+        }
+    }
+}
+
+// Extensions for NSAlert convenience
+private extension NSAlert {
+    static func runInformationAlert(title: String, message: String) {
+        let alert = NSAlert()
+        alert.messageText = title
+        alert.informativeText = message
+        alert.alertStyle = .informational
+        alert.addButton(withTitle: "OK")
+        alert.runModal()
+    }
+
+    static func runErrorAlert(title: String, message: String) {
+        let alert = NSAlert()
+        alert.messageText = title
+        alert.informativeText = message
+        alert.alertStyle = .critical
+        alert.addButton(withTitle: "OK")
+        alert.runModal()
+    }
+}
+
+#if DEBUG
+struct VMSnapshotHoverOverlay_Previews: PreviewProvider {
+    static var previews: some View {
+        VMSnapshotHoverOverlay()
+            .environmentObject(VMController.preview)
+            .frame(width: 400, height: 300)
+            .background(Color.blue.opacity(0.3))
+    }
+}
+#endif 

VirtualUI/Source/Session/VirtualMachineSessionView.swift

@@ -139,25 +139,35 @@ public struct VirtualMachineSessionView: View {
                 }
             }
             .animation(.bouncy, value: controller.state)
+
+            // Add hover overlay for screenshot functionality
+            VMSnapshotHoverOverlay()
+                .environmentObject(controller)
         }
     }
 
     private func startableStateView(with error: Error?) -> some View {
-        VStack(spacing: 28) {
-            if let error = error {
-                Text("The machine has stopped due to an error: \(String(describing: error))")
-                    .multilineTextAlignment(.center)
-                    .foregroundStyle(.secondary)
-                    .lineLimit(nil)
-                    .font(.caption)
+        ZStack {
+            VStack(spacing: 28) {
+                if let error = error {
+                    Text("The machine has stopped due to an error: \(String(describing: error))")
+                        .multilineTextAlignment(.center)
+                        .foregroundStyle(.secondary)
+                        .lineLimit(nil)
+                        .font(.caption)
+                }
+
+                circularStartButton
+
+                VMSessionConfigurationView()
+                    .environment(\.backgroundMaterial, Material.thin)
+                    .environmentObject(controller)
+                    .frame(maxWidth: 400)
             }
 
-            circularStartButton
-
-            VMSessionConfigurationView()
-                .environment(\.backgroundMaterial, Material.thin)
+            // Add hover overlay for screenshot functionality when VM is stopped/idle
+            VMSnapshotHoverOverlay()
                 .environmentObject(controller)
-                .frame(maxWidth: 400)
         }
     }