installer: make-dmg.sh — signed app DMG with /Applications symlink

Add ReturnsList (newest-first, max 8, click-to-Finder, hidden when empty)
and SettingsView (hotkey row, folder Choose… via FolderSettings + AppModel
seam mutators, async updateWatchFolder(url) only).

Sources/Shotdeck/AppModel.swift

@@ -0,0 +1,265 @@
+import AppKit
+import Carbon.HIToolbox
+import Foundation
+import Observation
+import SwiftUI
+import ShotdeckCore
+
+@MainActor
+public protocol SendCapable: AnyObject {
+    func send(anchor: NSView?) async
+}
+
+@MainActor
+public protocol SettingsWindowPresenting: AnyObject {
+    func presentSettingsWindow()
+}
+
+@MainActor
+public protocol ReturnsSectionProviding: AnyObject {
+    @ViewBuilder func returnsSection() -> AnyView
+}
+
+@MainActor
+@Observable
+public final class AppModel {
+    public private(set) var session: CaptureSession
+    public private(set) var region: CaptureRegion?
+    public private(set) var screenRecordingGranted: Bool
+    public private(set) var allReturns: [ReturnedDocument] = []
+    public private(set) var commentedReturns: [ReturnedDocument] = []
+    public private(set) var statusLine: String?
+    public private(set) var isCapturing: Bool = false
+    public private(set) var isSending: Bool = false
+    public private(set) var outboxDisplayName: String
+    public private(set) var watchFolderDisplayName: String
+    /// Live outbox; WP-4b reads this (not `paths.outbox`) so Settings folder changes take effect.
+    public private(set) var outboxURL: URL
+    /// Live watch folder; WP-4c updates this alongside `ReturnWatcher.updateWatchFolder`.
+    public private(set) var watchFolderURL: URL
+
+    let paths: AppSupportPaths
+    let spool: SpoolStore
+    let composer: PDFComposer
+    let capturer: ScreenCapturer
+    let hotkeys: HotkeyCenter
+    let picker: RegionPickerController
+    let ledger: ReturnLedger
+    let watcher: ReturnWatcher
+
+    public init(
+        paths: AppSupportPaths,
+        spool: SpoolStore,
+        composer: PDFComposer,
+        capturer: ScreenCapturer,
+        hotkeys: HotkeyCenter,
+        picker: RegionPickerController,
+        ledger: ReturnLedger,
+        watcher: ReturnWatcher
+    ) {
+        self.paths = paths
+        self.spool = spool
+        self.composer = composer
+        self.capturer = capturer
+        self.hotkeys = hotkeys
+        self.picker = picker
+        self.ledger = ledger
+        self.watcher = watcher
+        self.session = CaptureSession(
+            id: UUID(),
+            createdAt: Date(),
+            state: .open,
+            captures: [],
+            pdfFileName: nil
+        )
+        self.region = nil
+        self.screenRecordingGranted = ScreenCapturer.isScreenRecordingGranted
+        // Seeded from FolderSettings.resolve() via resolvedAppSupportPaths — never .standard().
+        let folders = FolderSettings.resolve()
+        self.outboxURL = folders.outbox
+        self.watchFolderURL = folders.watch
+        self.outboxDisplayName = folders.outbox.lastPathComponent
+        self.watchFolderDisplayName = folders.watch.lastPathComponent
+    }
+
+    // MARK: Seam mutators — the only way a WP-4b/4c extension changes state.
+
+    func setStatus(_ text: String?) { statusLine = text }
+    func setSending(_ value: Bool) { isSending = value }
+    func setCapturing(_ value: Bool) { isCapturing = value }
+    func replaceSession(_ new: CaptureSession) { session = new }
+    func replaceRegion(_ new: CaptureRegion?) { region = new }
+    func setReturns(all: [ReturnedDocument], commented: [ReturnedDocument]) {
+        allReturns = all
+        commentedReturns = commented
+    }
+    func setFolderDisplayNames(outbox: String, watch: String) {
+        outboxDisplayName = outbox
+        watchFolderDisplayName = watch
+    }
+    func setFolderURLs(outbox: URL, watch: URL) {
+        outboxURL = outbox
+        watchFolderURL = watch
+        setFolderDisplayNames(outbox: outbox.lastPathComponent, watch: watch.lastPathComponent)
+    }
+
+    public var iconState: MenuIconState {
+        if !screenRecordingGranted { return .recordingMissing }
+        if isCapturing { return .capturing }
+        if region == nil { return .noRegion }
+        if session.captures.isEmpty { return .regionEmpty }
+        return .hasCaptures(session.captures.count)
+    }
+
+    public func bootstrap() async {
+        if let data = UserDefaults.standard.data(forKey: CaptureRegion.defaultsKey),
+           let decoded = try? JSONDecoder().decode(CaptureRegion.self, from: data),
+           decoded.isStillValid {
+            replaceRegion(decoded)
+        }
+
+        do {
+            let recovered = try await spool.currentSession()
+            replaceSession(recovered)
+        } catch {
+            setStatus((error as? ShotdeckError)?.errorDescription ?? "Could not open the spool.")
+        }
+
+        do {
+            let initial = try await ledger.all()
+            let commented = try await ledger.commented()
+            setReturns(all: initial, commented: commented)
+        } catch {
+            // Empty ledger on first run is not an error.
+        }
+
+        do {
+            try await watcher.start { [weak self] _ in
+                Task { @MainActor in
+                    guard let self else { return }
+                    let all = (try? await self.ledger.all()) ?? []
+                    let commented = (try? await self.ledger.commented()) ?? []
+                    self.setReturns(all: all, commented: commented)
+                }
+            }
+        } catch {
+            setStatus((error as? ShotdeckError)?.errorDescription ?? "Could not watch the return folder.")
+        }
+
+        let registered = hotkeys.register(
+            id: "capture",
+            keyCode: UInt32(kVK_ANSI_2),
+            modifiers: UInt32(optionKey | shiftKey)
+        ) { [weak self] in
+            Task { await self?.captureNow() }
+        }
+        if !registered {
+            setStatus("⌥⇧2 is already used by another app — capture only works from the menu.")
+        }
+    }
+
+    public func captureNow() async {
+        guard !isCapturing else { return }
+        setCapturing(true)
+        defer { setCapturing(false) }
+
+        var target = region
+        if target == nil {
+            target = await withCheckedContinuation { (cont: CheckedContinuation<CaptureRegion?, Never>) in
+                picker.pick { picked in cont.resume(returning: picked) }
+            }
+            guard let picked = target else {
+                setStatus("No region selected.")
+                return
+            }
+            persistRegion(picked)
+        }
+        guard let region = target else { return }
+
+        do {
+            let image = try await capturer.capture(region)
+            let capture = try await spool.append(
+                pngData: image.pngData,
+                pixelWidth: image.pixelWidth,
+                pixelHeight: image.pixelHeight,
+                scale: image.scale,
+                capturedAt: Date()
+            )
+            replaceSession(try await spool.currentSession())
+            setStatus("Captured page \(capture.sequence).")
+        } catch {
+            screenRecordingGranted = ScreenCapturer.isScreenRecordingGranted
+            setStatus((error as? ShotdeckError)?.errorDescription ?? "The screenshot could not be taken.")
+        }
+    }
+
+    public func rePickRegion() async {
+        let picked = await withCheckedContinuation { (cont: CheckedContinuation<CaptureRegion?, Never>) in
+            picker.pick { cont.resume(returning: $0) }
+        }
+        guard let picked else { return }
+        persistRegion(picked)
+        setStatus("Region set: \(Int(picked.rect.width)) × \(Int(picked.rect.height)).")
+    }
+
+    public func removeCapture(id: UUID) async {
+        do {
+            // D-11: SpoolStore.remove MOVES the PNG to <session>/removed/; it is never unlinked.
+            replaceSession(try await spool.remove(captureID: id))
+        } catch {
+            setStatus((error as? ShotdeckError)?.errorDescription ?? "Could not remove that capture.")
+        }
+    }
+
+    public func copyCommentedLinks() async {
+        do {
+            let text = try await ledger.clipboardText()
+            let pasteboard = NSPasteboard.general
+            pasteboard.clearContents()
+            pasteboard.setString(text, forType: .string)
+            let count = commentedReturns.count
+            setStatus("Copied \(count) link\(count == 1 ? "" : "s").")
+        } catch {
+            setStatus((error as? ShotdeckError)?.errorDescription ?? "Nothing to copy.")
+        }
+    }
+
+    public func openSpoolFolder() {
+        NSWorkspace.shared.open(paths.spool)
+    }
+
+    public func openScreenRecordingSettings() {
+        guard let url = URL(string:
+            "x-apple.systempreferences:com.apple.preference.security?Privacy_ScreenCapture") else {
+            setStatus("Could not open System Settings.")
+            return
+        }
+        NSWorkspace.shared.open(url)
+    }
+
+    private func persistRegion(_ picked: CaptureRegion) {
+        replaceRegion(picked)
+        if let encoded = try? JSONEncoder().encode(picked) {
+            UserDefaults.standard.set(encoded, forKey: CaptureRegion.defaultsKey)
+        }
+    }
+}
+
+public enum MenuIconState: Equatable {
+    case noRegion, regionEmpty, hasCaptures(Int), capturing, recordingMissing
+
+    public var symbolName: String {
+        switch self {
+        case .noRegion: return "viewfinder"
+        case .regionEmpty: return "viewfinder.rectangular"
+        case .hasCaptures: return "viewfinder.rectangular"
+        case .capturing: return "viewfinder.circle.fill"
+        case .recordingMissing: return "exclamationmark.triangle"
+        }
+    }
+
+    public var countText: String? {
+        if case .hasCaptures(let n) = self { return "\(n)" }
+        return nil
+    }
+}

Sources/Shotdeck/MenuBarView.swift

@@ -0,0 +1,180 @@
+import AppKit
+import SwiftUI
+import ShotdeckCore
+
+struct MenuBarView: View {
+    @Environment(AppModel.self) private var model
+
+    var body: some View {
+        VStack(alignment: .leading, spacing: 8) {
+            statusRow
+            SessionStrip()
+            Divider()
+            actionsList
+            if !model.allReturns.isEmpty {
+                Divider()
+                returnsBlock
+            }
+        }
+        .padding(10)
+        .frame(width: 320, alignment: .leading)
+        .controlSize(.small)
+    }
+
+    @ViewBuilder
+    private var statusRow: some View {
+        if !model.screenRecordingGranted {
+            HStack(alignment: .top, spacing: 6) {
+                Image(systemName: "exclamationmark.triangle")
+                    .foregroundStyle(.yellow)
+                VStack(alignment: .leading, spacing: 4) {
+                    Text(
+                        ShotdeckError.screenRecordingNotGranted.errorDescription
+                            ?? "Screen Recording is turned off."
+                    )
+                    .font(.caption)
+                    .fixedSize(horizontal: false, vertical: true)
+                    Button("Open Screen Recording settings") {
+                        model.openScreenRecordingSettings()
+                    }
+                }
+            }
+        } else {
+            Text(model.statusLine ?? defaultStatusText)
+                .font(.caption)
+                .foregroundStyle(.primary)
+                .fixedSize(horizontal: false, vertical: true)
+        }
+    }
+
+    private var defaultStatusText: String {
+        guard let region = model.region else {
+            return "No region yet — press ⌥⇧2 to pick one."
+        }
+        let w = Int(region.rect.width)
+        let h = Int(region.rect.height)
+        let display = displayName(for: region)
+        if model.session.isEmpty {
+            return "Region \(w) × \(h) on \(display) · Nothing captured yet."
+        }
+        let count = model.session.captures.count
+        return "\(count) captures · region \(w) × \(h) on \(display)"
+    }
+
+    private func displayName(for region: CaptureRegion) -> String {
+        for (index, screen) in NSScreen.screens.enumerated() {
+            let id = (screen.deviceDescription[NSDeviceDescriptionKey("NSScreenNumber")] as? NSNumber)?
+                .uint32Value
+            if id == region.displayID {
+                return "Display \(index + 1)"
+            }
+        }
+        return "Display 1"
+    }
+
+    private var actionsList: some View {
+        VStack(alignment: .leading, spacing: 2) {
+            Button {
+                let anchor = NSApp.keyWindow?.contentView
+                if let sender = model as? SendCapable {
+                    Task { await sender.send(anchor: anchor) }
+                } else {
+                    model.setStatus("Send is not available in this build.")
+                }
+            } label: {
+                actionLabel("Send…")
+            }
+            .disabled(model.session.isEmpty || model.isSending)
+
+            Button {
+                Task { await model.captureNow() }
+            } label: {
+                actionLabel("Capture now", trailing: "⌥⇧2")
+            }
+            .disabled(model.isCapturing)
+
+            Button {
+                Task { await model.rePickRegion() }
+            } label: {
+                actionLabel("Re-select area")
+            }
+
+            Button {
+                Task { await model.copyCommentedLinks() }
+            } label: {
+                actionLabel(
+                    "Copy commented links",
+                    trailing: model.commentedReturns.isEmpty ? nil : "\(model.commentedReturns.count)"
+                )
+            }
+            .disabled(model.commentedReturns.isEmpty)
+
+            Button {
+                model.openSpoolFolder()
+            } label: {
+                actionLabel("Open spool folder")
+            }
+
+            Button {
+                if let presenter = model as? SettingsWindowPresenting {
+                    presenter.presentSettingsWindow()
+                } else {
+                    model.setStatus("Settings is not available in this build.")
+                }
+            } label: {
+                actionLabel("Settings…")
+            }
+
+            Button {
+                NSApp.terminate(nil)
+            } label: {
+                actionLabel("Quit Shotdeck")
+            }
+        }
+        .buttonStyle(.plain)
+    }
+
+    private func actionLabel(_ title: String, trailing: String? = nil) -> some View {
+        HStack(spacing: 8) {
+            Text(title)
+            Spacer(minLength: 8)
+            if let trailing {
+                Text(trailing)
+                    .foregroundStyle(.secondary)
+                    .monospacedDigit()
+            }
+        }
+        .frame(maxWidth: .infinity, alignment: .leading)
+        .contentShape(Rectangle())
+        .padding(.vertical, 3)
+    }
+
+    @ViewBuilder
+    private var returnsBlock: some View {
+        if let provider = model as? ReturnsSectionProviding {
+            provider.returnsSection()
+        } else {
+            VStack(alignment: .leading, spacing: 4) {
+                Text("Came back from your device")
+                    .font(.caption)
+                    .foregroundStyle(.secondary)
+                ForEach(newestReturns.prefix(8)) { doc in
+                    HStack(spacing: 8) {
+                        Text(doc.fileURL.lastPathComponent)
+                            .lineLimit(1)
+                        Spacer(minLength: 8)
+                        Text(doc.isCommented
+                             ? "\(doc.annotatedPages.count) page\(doc.annotatedPages.count == 1 ? "" : "s") marked"
+                             : "not marked")
+                            .font(.caption)
+                            .foregroundStyle(doc.isCommented ? .primary : .secondary)
+                    }
+                }
+            }
+        }
+    }
+
+    private var newestReturns: [ReturnedDocument] {
+        model.allReturns.sorted { $0.detectedAt > $1.detectedAt }
+    }
+}

Sources/Shotdeck/ReturnsList.swift

@@ -0,0 +1,53 @@
+import AppKit
+import SwiftUI
+import ShotdeckCore
+
+func newestReturnsForDisplay(_ returns: [ReturnedDocument], limit: Int = 8) -> [ReturnedDocument] {
+    Array(returns.sorted { $0.detectedAt > $1.detectedAt }.prefix(limit))
+}
+
+func returnMarkLabel(_ document: ReturnedDocument) -> String {
+    guard document.isCommented else { return "not marked" }
+    let count = document.annotatedPages.count
+    return "\(count) page\(count == 1 ? "" : "s") marked"
+}
+
+struct ReturnsList: View {
+    let returns: [ReturnedDocument]
+
+    var body: some View {
+        let visible = newestReturnsForDisplay(returns)
+        if visible.isEmpty {
+            EmptyView()
+        } else {
+            VStack(alignment: .leading, spacing: 4) {
+                Text("Came back from your device")
+                    .font(.caption)
+                    .foregroundStyle(.secondary)
+                ForEach(visible) { document in
+                    Button {
+                        NSWorkspace.shared.activateFileViewerSelecting([document.fileURL])
+                    } label: {
+                        HStack(spacing: 8) {
+                            Text(document.fileURL.lastPathComponent)
+                                .lineLimit(1)
+                            Spacer(minLength: 8)
+                            Text(returnMarkLabel(document))
+                                .font(.caption)
+                                .foregroundStyle(document.isCommented ? .primary : .secondary)
+                        }
+                    }
+                    .buttonStyle(.plain)
+                    .help(DubaiTime.stamp(document.detectedAt))
+                }
+            }
+        }
+    }
+}
+
+extension AppModel: ReturnsSectionProviding {
+    public func returnsSection() -> AnyView {
+        guard !allReturns.isEmpty else { return AnyView(EmptyView()) }
+        return AnyView(ReturnsList(returns: allReturns))
+    }
+}

Sources/Shotdeck/SendController.swift

@@ -0,0 +1,71 @@
+import AppKit
+import Darwin
+import Foundation
+import ShotdeckCore
+
+extension AppModel: SendCapable {
+    public func send(anchor: NSView?) async {
+        guard !session.isEmpty, !isSending else { return }
+        setSending(true)
+        defer { setSending(false) }
+
+        let workingSession = session
+        let composer = self.composer
+        // Live outbox (FolderSettings), not `paths.outbox` — Settings changes take effect.
+        let outboxDir = outboxURL
+        let sourceDir = paths.sessionDirectory(workingSession.id)
+        let fileName = PDFComposer.fileName(for: workingSession)
+        let finalURL = outboxDir.appendingPathComponent(fileName)
+        // Same directory as the final target so the rename below is same-volume (atomic).
+        let tempURL = outboxDir.appendingPathComponent(".shotdeck-\(UUID().uuidString).pdf")
+        let title = "Shotdeck – \(DubaiTime.stamp(workingSession.createdAt))"
+
+        do {
+            // D-13: build off the main actor. Only Sendable values cross into the
+            // detached task — never `anchor` (NSView is not Sendable).
+            try await Task.detached(priority: .userInitiated) {
+                _ = try composer.compose(
+                    session: workingSession,
+                    imageURL: { capture in sourceDir.appendingPathComponent(capture.fileName) },
+                    title: title,
+                    to: tempURL
+                )
+                // POSIX rename onto `finalURL` replaces any same-name file in one
+                // directory operation; there is never a window where the PDF is gone.
+                if Darwin.rename(tempURL.path, finalURL.path) != 0 {
+                    throw ShotdeckError.pdfCompositionFailed(
+                        reason: "could not publish the PDF: \(String(cString: strerror(errno)))"
+                    )
+                }
+                try AtomicFile.fsyncDirectory(at: outboxDir)
+            }.value
+
+            // File exists on disk now — archive only after that (D-13). A later AirDrop
+            // failure never deletes this file.
+            guard FileManager.default.fileExists(atPath: finalURL.path) else {
+                throw ShotdeckError.pdfCompositionFailed(reason: "the PDF was not written to disk")
+            }
+            _ = try await spool.archiveCurrent(pdfFileName: fileName)
+            replaceSession(try await spool.currentSession())
+
+            let pageWord = workingSession.captures.count == 1 ? "page" : "pages"
+            setStatus("Sent — \(workingSession.captures.count) \(pageWord).")
+
+            guard let anchor else {
+                setStatus("PDF saved to \(outboxDisplayName). Open the panel to AirDrop it.")
+                return
+            }
+            do {
+                try Sharing.airDrop(fileURL: finalURL, from: anchor)
+            } catch {
+                setStatus(
+                    "AirDrop is not available right now — the PDF is on your \(outboxDisplayName)."
+                )
+            }
+        } catch {
+            // Never unlink the published PDF, and never unlink `tempURL` either:
+            // a rename failure would leave the complete document at the temp name.
+            setStatus((error as? ShotdeckError)?.errorDescription ?? "The PDF could not be built.")
+        }
+    }
+}

Sources/Shotdeck/SessionStrip.swift

@@ -0,0 +1,78 @@
+import AppKit
+import SwiftUI
+import ShotdeckCore
+
+struct SessionStrip: View {
+    @Environment(AppModel.self) private var model
+
+    var body: some View {
+        if model.session.captures.isEmpty {
+            Text("Nothing captured yet.")
+                .font(.caption)
+                .foregroundStyle(.secondary)
+                .frame(maxWidth: .infinity, minHeight: 64, alignment: .leading)
+        } else {
+            ScrollView(.horizontal, showsIndicators: false) {
+                HStack(alignment: .top, spacing: 6) {
+                    ForEach(model.session.captures) { capture in
+                        SessionThumb(capture: capture)
+                    }
+                }
+            }
+            .frame(height: 64)
+        }
+    }
+}
+
+private struct SessionThumb: View {
+    @Environment(AppModel.self) private var model
+    let capture: Capture
+    @State private var hovering = false
+
+    var body: some View {
+        ZStack(alignment: .topLeading) {
+            thumbnail
+            Text("\(capture.sequence)")
+                .font(.system(size: 9, weight: .bold))
+                .foregroundStyle(.white)
+                .padding(.horizontal, 4)
+                .padding(.vertical, 1)
+                .background(.black.opacity(0.65))
+                .clipShape(RoundedRectangle(cornerRadius: 2, style: .continuous))
+                .padding(3)
+            if hovering {
+                VStack {
+                    Spacer()
+                    Button("Remove") {
+                        Task { await model.removeCapture(id: capture.id) }
+                    }
+                    .font(.system(size: 10, weight: .semibold))
+                    .buttonStyle(.plain)
+                    .foregroundStyle(.white)
+                    .frame(maxWidth: .infinity)
+                    .padding(.vertical, 3)
+                    .background(.black.opacity(0.7))
+                }
+            }
+        }
+        .frame(height: 64)
+        .clipped()
+        .onHover { hovering = $0 }
+        .help(DubaiTime.stamp(capture.capturedAt))
+    }
+
+    @ViewBuilder
+    private var thumbnail: some View {
+        let url = model.paths.sessionDirectory(model.session.id).appendingPathComponent(capture.fileName)
+        if let image = NSImage(contentsOf: url) {
+            Image(nsImage: image)
+                .resizable()
+                .aspectRatio(contentMode: .fit)
+                .frame(height: 64)
+        } else {
+            Rectangle()
+                .fill(Color.secondary.opacity(0.2))
+                .frame(width: 64, height: 64)
+        }
+    }
+}

Sources/Shotdeck/SettingsView.swift

@@ -0,0 +1,98 @@
+import AppKit
+import SwiftUI
+import ShotdeckCore
+
+struct SettingsView: View {
+    @Environment(AppModel.self) private var model
+
+    var body: some View {
+        Form {
+            Section("Hotkey") {
+                LabeledContent("Capture", value: "⌥⇧2 — fixed in this version")
+            }
+            Section("Folders") {
+                LabeledContent("Watch folder") {
+                    HStack(spacing: 8) {
+                        Text(model.watchFolderURL.path)
+                            .lineLimit(1)
+                            .truncationMode(.middle)
+                            .foregroundStyle(.secondary)
+                        Button("Choose…") { model.chooseWatchFolder() }
+                    }
+                }
+                LabeledContent("Output folder") {
+                    HStack(spacing: 8) {
+                        Text(model.outboxURL.path)
+                            .lineLimit(1)
+                            .truncationMode(.middle)
+                            .foregroundStyle(.secondary)
+                        Button("Choose…") { model.chooseOutboxFolder() }
+                    }
+                }
+            }
+            Section {
+                Button("Reveal spool folder") { model.openSpoolFolder() }
+            }
+        }
+        .padding()
+        .frame(width: 360)
+        .controlSize(.small)
+    }
+}
+
+extension AppModel: SettingsWindowPresenting {
+    private static var settingsWindowController: NSWindowController?
+
+    public func presentSettingsWindow() {
+        if let existing = Self.settingsWindowController {
+            existing.window?.makeKeyAndOrderFront(nil)
+            NSApp.activate()
+            return
+        }
+        let hosting = NSHostingController(rootView: SettingsView().environment(self))
+        let window = NSWindow(contentViewController: hosting)
+        window.title = "Shotdeck Settings"
+        window.styleMask = [.titled, .closable]
+        window.isReleasedWhenClosed = false
+        window.center()
+        let controller = NSWindowController(window: window)
+        Self.settingsWindowController = controller
+        controller.showWindow(nil)
+        NSApp.activate()
+    }
+
+    func chooseOutboxFolder() {
+        guard let url = chooseDirectory(startingAt: outboxURL) else { return }
+        FolderSettings.setOutbox(url)
+        setFolderURLs(outbox: url, watch: watchFolderURL)
+        setStatus("Output folder set to \(url.lastPathComponent).")
+    }
+
+    func chooseWatchFolder() {
+        guard let url = chooseDirectory(startingAt: watchFolderURL) else { return }
+        FolderSettings.setWatchFolder(url)
+        setFolderURLs(outbox: outboxURL, watch: url)
+        Task {
+            do {
+                try await watcher.updateWatchFolder(url)
+                setStatus("Watch folder set to \(url.lastPathComponent).")
+            } catch {
+                setStatus(
+                    (error as? ShotdeckError)?.errorDescription ?? "Could not switch the watch folder."
+                )
+            }
+        }
+    }
+
+    private func chooseDirectory(startingAt directory: URL) -> URL? {
+        let panel = NSOpenPanel()
+        panel.canChooseDirectories = true
+        panel.canChooseFiles = false
+        panel.allowsMultipleSelection = false
+        panel.canCreateDirectories = true
+        panel.prompt = "Choose"
+        panel.directoryURL = directory
+        guard panel.runModal() == .OK else { return nil }
+        return panel.url
+    }
+}

Sources/Shotdeck/Sharing.swift

@@ -0,0 +1,83 @@
+import AppKit
+import ShotdeckCore
+
+@MainActor
+enum Sharing {
+    /// Presents the AirDrop picker for `fileURL`, anchored to `view`.
+    /// Throws `ShotdeckError.airDropUnavailable` when the service cannot be created,
+    /// `canPerform` is false, or `view` is not in a visible window (a detached view
+    /// never produces an on-screen sheet).
+    static func airDrop(fileURL: URL, from view: NSView) throws {
+        guard let service = NSSharingService(named: .sendViaAirDrop),
+              service.canPerform(withItems: [fileURL]) else {
+            throw ShotdeckError.airDropUnavailable
+        }
+        // Presenting from a detached NSView (no window) yields a sheet that never appears.
+        guard let window = view.window, window.isVisible else {
+            throw ShotdeckError.airDropUnavailable
+        }
+
+        NSApp.activate()
+        window.makeKeyAndOrderFront(nil)
+
+        service.subject = fileURL.lastPathComponent
+        let session = AirDropSession(service: service, window: window, view: view)
+        AirDropSession.keepAlive(session)
+        service.delegate = session
+        service.perform(withItems: [fileURL])
+    }
+}
+
+/// Retains the sharing service for the life of the picker and supplies the real
+/// on-screen window as the sheet parent. `NSSharingService.delegate` is weak.
+@MainActor
+private final class AirDropSession: NSObject, NSSharingServiceDelegate {
+    static var live: [AirDropSession] = []
+
+    let service: NSSharingService
+    let window: NSWindow
+    let view: NSView
+
+    init(service: NSSharingService, window: NSWindow, view: NSView) {
+        self.service = service
+        self.window = window
+        self.view = view
+    }
+
+    static func keepAlive(_ session: AirDropSession) {
+        live.append(session)
+    }
+
+    private func drop() {
+        Self.live.removeAll { $0 === self }
+    }
+
+    func sharingService(
+        _ sharingService: NSSharingService,
+        sourceWindowForShareItems items: [Any],
+        sharingContentScope: UnsafeMutablePointer<NSSharingService.SharingContentScope>
+    ) -> NSWindow? {
+        sharingContentScope.pointee = .item
+        return window
+    }
+
+    func sharingService(
+        _ sharingService: NSSharingService,
+        sourceFrameOnScreenForShareItem item: Any
+    ) -> NSRect {
+        let inWindow = view.convert(view.bounds, to: nil)
+        return window.convertToScreen(inWindow)
+    }
+
+    func sharingService(_ sharingService: NSSharingService, didShareItems items: [Any]) {
+        drop()
+    }
+
+    func sharingService(
+        _ sharingService: NSSharingService,
+        didFailToShareItems items: [Any],
+        error: any Error
+    ) {
+        drop()
+    }
+}

Sources/Shotdeck/main.swift

@@ -1,6 +1,75 @@
 import AppKit
+import SwiftUI
+import ShotdeckCore
 
-// WP-4 replaces this body with the real menu-bar UI.
+// SwiftPM treats a file named main.swift as top-level code, which forbids `@main`.
-let application = NSApplication.shared
+// App.main() is the equivalent entry point.
-application.setActivationPolicy(.accessory)
+ShotdeckApp.main()
-application.run()
+
+struct ShotdeckApp: App {
+    @NSApplicationDelegateAdaptor(AppDelegate.self) private var appDelegate
+
+    var body: some Scene {
+        MenuBarExtra {
+            MenuBarView()
+                .environment(appDelegate.model)
+        } label: {
+            let state = appDelegate.model.iconState
+            HStack(spacing: 4) {
+                Image(systemName: state.symbolName)
+                if let count = state.countText {
+                    Text(count).font(.system(size: 11, weight: .semibold))
+                }
+            }
+            .accessibilityLabel("Shotdeck")
+        }
+        .menuBarExtraStyle(.window)
+    }
+}
+
+@MainActor
+final class AppDelegate: NSObject, NSApplicationDelegate {
+    let model: AppModel
+
+    override init() {
+        NSApplication.shared.setActivationPolicy(.accessory)
+        model = AppDelegate.makeLaunchModel()
+        super.init()
+    }
+
+    func applicationDidFinishLaunching(_ notification: Notification) {
+        Task { await model.bootstrap() }
+    }
+
+    private static func makeLaunchModel() -> AppModel {
+        do {
+            let paths = try FolderSettings.resolvedAppSupportPaths()
+            return try makeModel(paths: paths)
+        } catch {
+            Log.ui.critical(
+                "AppModel init failed: \(String(describing: error), privacy: .public)"
+            )
+            let tmp = FileManager.default.temporaryDirectory
+            let fallbackRoot = tmp.appendingPathComponent("Shotdeck-fallback", isDirectory: true)
+            // Safe: temp-dir creation for a path this process controls cannot legitimately fail.
+            let fallback = try! AppSupportPaths(root: fallbackRoot, outbox: tmp, watchFolder: tmp)
+            let model = try! makeModel(paths: fallback)
+            model.setStatus("Shotdeck could not access its storage folder. Captures will not persist.")
+            return model
+        }
+    }
+
+    private static func makeModel(paths: AppSupportPaths) throws -> AppModel {
+        let ledger = try ReturnLedger(paths: paths)
+        return AppModel(
+            paths: paths,
+            spool: try SpoolStore(paths: paths),
+            composer: PDFComposer(),
+            capturer: ScreenCapturer(),
+            hotkeys: HotkeyCenter(),
+            picker: RegionPickerController(),
+            ledger: ledger,
+            watcher: ReturnWatcher(paths: paths, ledger: ledger)
+        )
+    }
+}

scripts/make-dmg.sh

@@ -0,0 +1,95 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+cd "$ROOT"
+
+APP_BUNDLE="${ROOT}/.build/Shotdeck.app"
+STAGING="${ROOT}/.build/dmg-staging"
+DMG="${ROOT}/.build/Shotdeck.dmg"
+MOUNT_POINT="${ROOT}/.build/dmg-mnt"
+
+SKIP_SIGN=0
+for arg in "$@"; do
+    case "${arg}" in
+        --skip-sign)
+            SKIP_SIGN=1
+            ;;
+        *)
+            echo "Unknown argument: ${arg}" >&2
+            echo "Usage: $0 [--skip-sign]" >&2
+            exit 1
+            ;;
+    esac
+done
+
+echo "==> Building Shotdeck.app"
+if [[ "${SKIP_SIGN}" -eq 1 ]]; then
+    ./scripts/build-app.sh --skip-sign
+else
+    ./scripts/build-app.sh
+fi
+
+if [[ ! -d "${APP_BUNDLE}" ]]; then
+    echo "App bundle not found at ${APP_BUNDLE}" >&2
+    exit 1
+fi
+
+echo "==> Staging DMG contents"
+rm -rf "${STAGING}"
+mkdir -p "${STAGING}"
+ditto "${APP_BUNDLE}" "${STAGING}/Shotdeck.app"
+ln -s /Applications "${STAGING}/Applications"
+
+echo "==> Creating ${DMG}"
+mkdir -p "$(dirname "${DMG}")"
+hdiutil create -volname "Shotdeck" -srcfolder "${STAGING}" -ov -format UDZO "${DMG}"
+
+MOUNTED=0
+detach_dmg() {
+    if [[ "${MOUNTED}" -eq 1 ]]; then
+        hdiutil detach "${MOUNT_POINT}" || hdiutil detach "${MOUNT_POINT}" -force || true
+        MOUNTED=0
+    fi
+}
+trap detach_dmg EXIT
+
+if [[ -d "${MOUNT_POINT}" ]] && /sbin/mount | grep -F -q "${MOUNT_POINT}"; then
+    hdiutil detach "${MOUNT_POINT}" || hdiutil detach "${MOUNT_POINT}" -force
+fi
+rm -rf "${MOUNT_POINT}"
+mkdir -p "${MOUNT_POINT}"
+
+echo "==> Verifying ${DMG}"
+hdiutil attach "${DMG}" -nobrowse -readonly -mountpoint "${MOUNT_POINT}"
+MOUNTED=1
+
+echo "==> Mount contents"
+ls -la "${MOUNT_POINT}"
+
+if [[ ! -d "${MOUNT_POINT}/Shotdeck.app" ]]; then
+    echo "Verification failed: Shotdeck.app missing from mounted DMG" >&2
+    exit 1
+fi
+if [[ ! -L "${MOUNT_POINT}/Applications" ]]; then
+    echo "Verification failed: Applications symlink missing from mounted DMG" >&2
+    exit 1
+fi
+if [[ "$(readlink "${MOUNT_POINT}/Applications")" != "/Applications" ]]; then
+    echo "Verification failed: Applications does not point at /Applications" >&2
+    exit 1
+fi
+
+echo "==> codesign --verify --deep"
+codesign --verify --deep --verbose=2 "${MOUNT_POINT}/Shotdeck.app"
+
+echo "==> Detaching ${MOUNT_POINT}"
+hdiutil detach "${MOUNT_POINT}"
+MOUNTED=0
+trap - EXIT
+
+SHA256="$(shasum -a 256 "${DMG}" | awk '{print $1}')"
+
+echo
+echo "DMG path: ${DMG}"
+echo "SHA256: ${SHA256}"