Add macOS menu bar agent mode

JavaDaemonWatcher/JavaDaemonWatcher.xcodeproj/project.pbxproj

@@ -24,6 +24,7 @@
 		A10000015 /* SettingsView.swift in Sources */ = {isa = PBXBuildFile; fileRef = B10000015; };
 		A10000016 /* ShellExecutor.swift in Sources */ = {isa = PBXBuildFile; fileRef = B10000016; };
 		A10000017 /* Formatters.swift in Sources */ = {isa = PBXBuildFile; fileRef = B10000017; };
+		A10000019 /* main.swift in Sources */ = {isa = PBXBuildFile; fileRef = B10000019; };
 		A10000018 /* Assets.xcassets in Resources */ = {isa = PBXBuildFile; fileRef = B10000018; };
 /* End PBXBuildFile section */
 
@@ -46,6 +47,7 @@
 		B10000015 /* SettingsView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SettingsView.swift; sourceTree = "<group>"; };
 		B10000016 /* ShellExecutor.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ShellExecutor.swift; sourceTree = "<group>"; };
 		B10000017 /* Formatters.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Formatters.swift; sourceTree = "<group>"; };
+		B10000019 /* main.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = main.swift; sourceTree = "<group>"; };
 		D10000001 /* Info.plist */ = {isa = PBXFileReference; lastKnownFileType = text.plist.xml; path = Info.plist; sourceTree = "<group>"; };
 		D10000002 /* JavaDaemonWatcher.entitlements */ = {isa = PBXFileReference; lastKnownFileType = text.plist.entitlements; path = JavaDaemonWatcher.entitlements; sourceTree = "<group>"; };
 		B10000018 /* Assets.xcassets */ = {isa = PBXFileReference; lastKnownFileType = folder.assetcatalog; path = Assets.xcassets; sourceTree = "<group>"; };
@@ -90,6 +92,7 @@
 		F10000003 /* App */ = {
 			isa = PBXGroup;
 			children = (
+				B10000019 /* main.swift */,
 				B10000001 /* JavaDaemonWatcherApp.swift */,
 			);
 			path = App;
@@ -247,6 +250,7 @@
 				A10000015 /* SettingsView.swift in Sources */,
 				A10000016 /* ShellExecutor.swift in Sources */,
 				A10000017 /* Formatters.swift in Sources */,
+				A10000019 /* main.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};

JavaDaemonWatcher/JavaDaemonWatcher/App/JavaDaemonWatcherApp.swift

@@ -1,27 +1,111 @@
+import AppKit
 import SwiftUI
 
-@main
-struct JavaDaemonWatcherApp: App {
-    @NSApplicationDelegateAdaptor(AppDelegate.self) var delegate
-    @State private var viewModel = DaemonWatcherViewModel()
-
-    var body: some Scene {
-        WindowGroup {
-            MenuBarView(viewModel: viewModel)
-                .onAppear {
-                    viewModel.start()
-                }
-        }
-        .defaultSize(width: 400, height: 500)
-    }
-}
+@MainActor
+final class AppDelegate: NSObject, NSApplicationDelegate, NSWindowDelegate {
+    private let popoverSize = NSSize(width: 360, height: 280)
+    private let windowSize = NSSize(width: 420, height: 340)
+    private let viewModel = DaemonWatcherViewModel()
+    private let popover = NSPopover()
+    private var statusItem: NSStatusItem?
+    private var mainWindow: NSWindow?
 
-final class AppDelegate: NSObject, NSApplicationDelegate {
     func applicationDidFinishLaunching(_ notification: Notification) {
-        // Ensure the window is visible on launch
-        if let window = NSApplication.shared.windows.first {
-            window.makeKeyAndOrderFront(nil)
+        NSApplication.shared.setActivationPolicy(.accessory)
+
+        viewModel.start()
+        configurePopover()
+        configureStatusItem()
+        showMainWindow()
+    }
+
+    func applicationShouldTerminateAfterLastWindowClosed(_ sender: NSApplication) -> Bool {
+        false
+    }
+
+    func applicationShouldHandleReopen(_ sender: NSApplication, hasVisibleWindows flag: Bool) -> Bool {
+        showMainWindow()
+        return true
+    }
+
+    private func configurePopover() {
+        let rootView = MenuBarView(
+            viewModel: viewModel,
+            onOpenWindow: { [weak self] in
+                self?.showMainWindow()
+                self?.popover.performClose(nil)
+            }
+        )
+        .frame(width: popoverSize.width, height: popoverSize.height, alignment: .top)
+
+        popover.behavior = .transient
+        popover.contentSize = popoverSize
+        popover.contentViewController = NSHostingController(rootView: rootView)
+    }
+
+    private func configureStatusItem() {
+        let statusItem = NSStatusBar.system.statusItem(withLength: NSStatusItem.squareLength)
+        guard let button = statusItem.button else { return }
+
+        button.image = MenuBarIconProvider.icon()
+        button.imagePosition = .imageOnly
+        button.imageScaling = .scaleProportionallyUpOrDown
+        button.toolTip = "Java Daemon Watcher"
+        button.target = self
+        button.action = #selector(togglePopover(_:))
+
+        self.statusItem = statusItem
+    }
+
+    private func showMainWindow() {
+        if mainWindow == nil {
+            createMainWindow()
         }
+
+        guard let mainWindow else { return }
+        NSApplication.shared.setActivationPolicy(.regular)
+        mainWindow.makeKeyAndOrderFront(nil)
         NSApplication.shared.activate(ignoringOtherApps: true)
     }
+
+    private func createMainWindow() {
+        let rootView = MenuBarView(viewModel: viewModel)
+        let hostingController = NSHostingController(rootView: rootView)
+        let window = NSWindow(contentViewController: hostingController)
+
+        window.title = "Java Daemon Watcher"
+        window.styleMask = [.titled, .closable, .miniaturizable, .resizable]
+        window.setContentSize(windowSize)
+        window.minSize = NSSize(width: 360, height: 300)
+        window.center()
+        window.isReleasedWhenClosed = false
+        window.delegate = self
+
+        mainWindow = window
+    }
+
+    func windowWillClose(_ notification: Notification) {
+        NSApplication.shared.setActivationPolicy(.accessory)
+    }
+
+    @objc
+    private func togglePopover(_ sender: Any?) {
+        guard let button = statusItem?.button else { return }
+
+        if popover.isShown {
+            popover.performClose(sender)
+        } else {
+            popover.show(relativeTo: button.bounds, of: button, preferredEdge: .minY)
+            NSApplication.shared.activate(ignoringOtherApps: true)
+        }
+    }
+}
+
+private enum MenuBarIconProvider {
+    @MainActor
+    static func icon() -> NSImage {
+        let icon = NSApp.applicationIconImage.copy() as? NSImage ?? NSImage()
+        icon.size = NSSize(width: 18, height: 18)
+        return icon
+    }
 }

JavaDaemonWatcher/JavaDaemonWatcher/App/main.swift

@@ -0,0 +1,6 @@
+import AppKit
+
+let app = NSApplication.shared
+let delegate = AppDelegate()
+app.delegate = delegate
+app.run()

JavaDaemonWatcher/JavaDaemonWatcher/Info.plist

@@ -4,5 +4,7 @@
 <dict>
 	<key>CFBundleDisplayName</key>
 	<string>Java Daemon Watcher</string>
+	<key>LSUIElement</key>
+	<true/>
 </dict>
 </plist>

JavaDaemonWatcher/JavaDaemonWatcher/Views/MenuBarView.swift

@@ -2,6 +2,7 @@ import SwiftUI
 
 struct MenuBarView: View {
     @Bindable var viewModel: DaemonWatcherViewModel
+    var onOpenWindow: (() -> Void)? = nil
     @State private var showSettings = false
     @State private var errorDismissTask: Task<Void, Never>?
 
@@ -17,7 +18,7 @@ struct MenuBarView: View {
                 mainContent
             }
         }
-        .frame(minWidth: 320)
+        .frame(minWidth: 320, maxWidth: .infinity, maxHeight: .infinity, alignment: .top)
         .onChange(of: viewModel.errorMessage) { _, newValue in
             errorDismissTask?.cancel()
             if newValue != nil {
@@ -56,6 +57,7 @@ struct MenuBarView: View {
             Divider()
             footer
         }
+        .frame(maxWidth: .infinity, maxHeight: .infinity, alignment: .top)
     }
 
     // MARK: - Header
@@ -153,7 +155,7 @@ struct MenuBarView: View {
                 .foregroundStyle(.secondary)
         }
         .frame(maxWidth: .infinity)
-        .padding(.vertical, 28)
+        .padding(.vertical, 18)
     }
 
     // MARK: - Daemon List
@@ -194,7 +196,7 @@ struct MenuBarView: View {
                 freed: viewModel.statistics.allTimeFreedBytes
             )
         }
-        .padding(.vertical, 8)
+        .padding(.vertical, 6)
     }
 
     private func statColumn(label: String, clears: Int, freed: UInt64) -> some View {
@@ -228,6 +230,15 @@ struct MenuBarView: View {
                 .foregroundStyle(.red)
             }
 
+            if let onOpenWindow {
+                Button("Open window") {
+                    onOpenWindow()
+                }
+                .buttonStyle(.borderless)
+                .font(.caption)
+                .foregroundStyle(.secondary)
+            }
+
             Spacer()
 
             Button("Quit") {
@@ -238,6 +249,6 @@ struct MenuBarView: View {
             .foregroundStyle(.secondary)
         }
         .padding(.horizontal, 14)
-        .padding(.vertical, 8)
+        .padding(.vertical, 6)
     }
 }

JavaDaemonWatcher/JavaDaemonWatcher/Views/SettingsView.swift

@@ -84,6 +84,8 @@ struct SettingsView: View {
                     .padding(.horizontal, 14)
                     .padding(.vertical, 10)
             }
+            .frame(maxWidth: .infinity, maxHeight: .infinity, alignment: .top)
         }
+        .frame(maxWidth: .infinity, maxHeight: .infinity, alignment: .top)
     }
 }