WP-3b: ScreenCaptureKit capturer + region picker overlay per SPEC-A2a

Sources/Shotdeck/RegionPickerController.swift

@@ -0,0 +1,181 @@
+import AppKit
+import ShotdeckCore
+
+@MainActor
+public final class RegionPickerController {
+    private var windows: [RegionPickerWindow] = []
+    private var monitor: Any?
+    private var completion: (@MainActor (CaptureRegion?) -> Void)?
+    private var dragStart: NSPoint?
+    private var startScreen: NSScreen?
+    private var cursorPushed = false
+
+    public init() {}
+
+    /// Presents one overlay per attached screen. A pick already in progress is cancelled
+    /// (its completion called with nil) before the new one starts — never leaves a caller
+    /// waiting forever on a dropped re-entrant call.
+    public func pick(completion: @escaping @MainActor (CaptureRegion?) -> Void) {
+        if self.completion != nil {
+            finish(region: nil)
+        }
+        self.completion = completion
+        presentOverlays()
+    }
+
+    private func presentOverlays() {
+        let screens = NSScreen.screens
+        guard !screens.isEmpty else {
+            finish(region: nil)
+            return
+        }
+
+        NSCursor.crosshair.push()
+        cursorPushed = true
+
+        windows = screens.map { RegionPickerWindow(screen: $0) }
+        for window in windows {
+            window.orderFrontRegardless()
+        }
+        // Nonactivating panel can become key without activating the app; needed so
+        // Escape reaches the local monitor immediately, before any mouse click.
+        let mouse = NSEvent.mouseLocation
+        let keyWindow = windows.first(where: { $0.coveringScreen.frame.contains(mouse) })
+            ?? windows[0]
+        keyWindow.makeKey()
+
+        monitor = NSEvent.addLocalMonitorForEvents(
+            matching: [.leftMouseDown, .leftMouseDragged, .leftMouseUp, .keyDown]
+        ) { [weak self] event in
+            guard let self else { return event }
+            // NSEvent is not Sendable; lift the two Sendable fields the handler
+            // needs. Mouse geometry is read from NSEvent.mouseLocation on the
+            // main thread inside the isolated methods, per spec.
+            let type = event.type
+            let keyCode = event.keyCode
+            let consume = MainActor.assumeIsolated {
+                self.handle(type: type, keyCode: keyCode)
+            }
+            return consume ? nil : event
+        }
+    }
+
+    /// Returns `true` when the event should be swallowed.
+    private func handle(type: NSEvent.EventType, keyCode: UInt16) -> Bool {
+        switch type {
+        case .keyDown:
+            if keyCode == 53 { // kVK_Escape
+                finish(region: nil)
+                return true
+            }
+            return false
+        case .leftMouseDown:
+            handleMouseDown()
+            return false
+        case .leftMouseDragged:
+            handleMouseDragged()
+            return false
+        case .leftMouseUp:
+            handleMouseUp()
+            return false
+        default:
+            return false
+        }
+    }
+
+    private func handleMouseDown() {
+        let point = NSEvent.mouseLocation
+        dragStart = point
+        startScreen = NSScreen.screens.first(where: { $0.frame.contains(point) })
+            ?? NSScreen.screens.first
+        guard let startScreen else { return }
+        let local = Self.localRect(
+            from: CGRect(origin: point, size: .zero).intersection(startScreen.frame),
+            on: startScreen
+        )
+        window(for: startScreen)?.updateSelection(localRect: local, sizeText: "0 x 0")
+        for window in windows where window.coveringScreen !== startScreen {
+            window.updateSelection(localRect: nil, sizeText: nil)
+        }
+    }
+
+    private func handleMouseDragged() {
+        guard dragStart != nil, startScreen != nil else { return }
+        applyLiveSelection()
+    }
+
+    private func handleMouseUp() {
+        guard let startScreen else {
+            dragStart = nil
+            return
+        }
+        guard let rect = currentClampedRect(), rect.width >= 8, rect.height >= 8 else {
+            // Mis-click: reset drag state, leave every window open and fully dimmed.
+            dragStart = nil
+            self.startScreen = nil
+            for window in windows {
+                window.updateSelection(localRect: nil, sizeText: nil)
+            }
+            return
+        }
+        let region = CaptureRegion.fromAppKit(rect: rect, on: startScreen)
+        finish(region: region)
+    }
+
+    private func applyLiveSelection() {
+        guard let startScreen, let rect = currentClampedRect() else { return }
+        let local = Self.localRect(from: rect, on: startScreen)
+        let text = "\(Int(rect.width)) x \(Int(rect.height))"
+        window(for: startScreen)?.updateSelection(localRect: local, sizeText: text)
+        for window in windows where window.coveringScreen !== startScreen {
+            window.updateSelection(localRect: nil, sizeText: nil)
+        }
+    }
+
+    /// Normalize the drag (so bottom-right → up-left is not misjudged) then clamp
+    /// to the screen the gesture started on — never selects across displays.
+    private func currentClampedRect() -> CGRect? {
+        guard let dragStart, let startScreen else { return nil }
+        let current = NSEvent.mouseLocation
+        let normalized = CGRect(
+            x: min(dragStart.x, current.x),
+            y: min(dragStart.y, current.y),
+            width: abs(current.x - dragStart.x),
+            height: abs(current.y - dragStart.y)
+        )
+        return normalized.intersection(startScreen.frame)
+    }
+
+    private func window(for screen: NSScreen) -> RegionPickerWindow? {
+        windows.first { $0.coveringScreen === screen }
+    }
+
+    private static func localRect(from rect: CGRect, on screen: NSScreen) -> CGRect {
+        CGRect(
+            x: rect.minX - screen.frame.minX,
+            y: rect.minY - screen.frame.minY,
+            width: rect.width,
+            height: rect.height
+        )
+    }
+
+    private func finish(region: CaptureRegion?) {
+        if let monitor {
+            NSEvent.removeMonitor(monitor)
+            self.monitor = nil
+        }
+        if cursorPushed {
+            NSCursor.pop()
+            cursorPushed = false
+        }
+        for window in windows {
+            window.orderOut(nil)
+        }
+        windows.removeAll()
+        dragStart = nil
+        startScreen = nil
+        let done = completion
+        completion = nil
+        done?(region)
+    }
+}

Sources/Shotdeck/RegionPickerWindow.swift

@@ -0,0 +1,110 @@
+import AppKit
+
+/// Full-screen dim overlay for one attached display. Subclasses `NSPanel` with
+/// `.nonactivatingPanel` so it can accept mouse and key events without activating
+/// Shotdeck or stealing the frontmost app beyond those events.
+@MainActor
+final class RegionPickerWindow: NSPanel {
+    let coveringScreen: NSScreen
+    private let pickerView: RegionPickerView
+
+    init(screen: NSScreen) {
+        self.coveringScreen = screen
+        self.pickerView = RegionPickerView(frame: CGRect(origin: .zero, size: screen.frame.size))
+        super.init(
+            contentRect: screen.frame,
+            styleMask: [.borderless, .nonactivatingPanel],
+            backing: .buffered,
+            defer: false
+        )
+        setFrame(screen.frame, display: false)
+        level = .screenSaver
+        isOpaque = false
+        backgroundColor = .clear
+        ignoresMouseEvents = false
+        hasShadow = false
+        isMovable = false
+        hidesOnDeactivate = false
+        isFloatingPanel = true
+        becomesKeyOnlyIfNeeded = false
+        animationBehavior = .none
+        collectionBehavior = [.canJoinAllSpaces, .fullScreenAuxiliary, .stationary]
+        contentView = pickerView
+    }
+
+    override var canBecomeKey: Bool { true }
+    override var canBecomeMain: Bool { false }
+
+    /// `localRect` is in this window's coordinates (screen.frame origin subtracted).
+    /// Pass `nil` to restore the full dim with no punch and no size chip.
+    func updateSelection(localRect: CGRect?, sizeText: String?) {
+        pickerView.selectionLocalRect = localRect
+        pickerView.sizeChipText = sizeText
+        pickerView.needsDisplay = true
+    }
+}
+
+/// Draws ~35% black over the screen with an even-odd punch for the live selection,
+/// a thin light border, and the size-readout chip.
+@MainActor
+private final class RegionPickerView: NSView {
+    var selectionLocalRect: CGRect?
+    var sizeChipText: String?
+
+    override var isOpaque: Bool { false }
+    override var acceptsFirstResponder: Bool { true }
+
+    override func draw(_ dirtyRect: NSRect) {
+        super.draw(dirtyRect)
+
+        let dim = NSColor.black.withAlphaComponent(0.35)
+        let path = NSBezierPath(rect: bounds)
+        if let sel = selectionLocalRect, sel.width > 0, sel.height > 0 {
+            path.append(NSBezierPath(rect: sel))
+            path.windingRule = .evenOdd
+        }
+        dim.setFill()
+        path.fill()
+
+        guard let sel = selectionLocalRect, sel.width > 0, sel.height > 0 else { return }
+
+        NSColor.white.withAlphaComponent(0.85).setStroke()
+        let border = NSBezierPath(rect: sel)
+        border.lineWidth = 1
+        border.stroke()
+
+        if let text = sizeChipText {
+            drawSizeChip(text, above: sel)
+        }
+    }
+
+    private func drawSizeChip(_ text: String, above sel: CGRect) {
+        let attrs: [NSAttributedString.Key: Any] = [
+            .font: NSFont.systemFont(ofSize: NSFont.smallSystemFontSize),
+            .foregroundColor: NSColor.white,
+        ]
+        let nsText = text as NSString
+        let textSize = nsText.size(withAttributes: attrs)
+        let padX: CGFloat = 8
+        let padY: CGFloat = 4
+        let chipSize = CGSize(
+            width: ceil(textSize.width) + padX * 2,
+            height: ceil(textSize.height) + padY * 2
+        )
+
+        var origin = CGPoint(x: sel.minX, y: sel.maxY + 6)
+        if origin.y + chipSize.height > bounds.maxY {
+            origin.y = sel.minY - 6 - chipSize.height
+        }
+        origin.x = min(max(origin.x, bounds.minX + 4), bounds.maxX - chipSize.width - 4)
+        origin.y = min(max(origin.y, bounds.minY + 4), bounds.maxY - chipSize.height - 4)
+
+        let chipRect = CGRect(origin: origin, size: chipSize)
+        NSColor.black.withAlphaComponent(0.75).setFill()
+        NSBezierPath(roundedRect: chipRect, xRadius: 4, yRadius: 4).fill()
+        nsText.draw(
+            at: CGPoint(x: chipRect.minX + padX, y: chipRect.minY + padY),
+            withAttributes: attrs
+        )
+    }
+}

Sources/ShotdeckCore/Capture/ScreenCapturer.swift

@@ -0,0 +1,118 @@
+import ScreenCaptureKit
+import CoreGraphics
+import ImageIO
+import UniformTypeIdentifiers
+import AppKit  // NSScreen only, to read backingScaleFactor as a fallback
+import Foundation
+
+public struct CapturedImage: Sendable {
+    public let pngData: Data
+    public let pixelWidth: Int
+    public let pixelHeight: Int
+    public let scale: CGFloat
+}
+
+public struct ScreenCapturer: Sendable {
+    public init() {}
+
+    /// Does NOT prompt. Reports the current Screen Recording grant.
+    public static var isScreenRecordingGranted: Bool { CGPreflightScreenCaptureAccess() }
+
+    /// Captures `region` at the display's true backing scale. Throws
+    /// `.screenRecordingNotGranted` when the grant is absent — never requests it.
+    public func capture(_ region: CaptureRegion) async throws -> CapturedImage {
+        guard Self.isScreenRecordingGranted else {
+            throw ShotdeckError.screenRecordingNotGranted
+        }
+
+        let content: SCShareableContent
+        do {
+            content = try await SCShareableContent.excludingDesktopWindows(
+                false,
+                onScreenWindowsOnly: true
+            )
+        } catch {
+            throw ShotdeckError.captureFailed(underlying: error.localizedDescription)
+        }
+
+        guard let display = content.displays.first(where: { $0.displayID == region.displayID }) else {
+            throw ShotdeckError.displayNoLongerConnected(displayID: region.displayID)
+        }
+
+        // Bounds/clamp: a resolution change often shrinks the display bounds by a few
+        // points without the region Ben picked being meaningfully wrong; 80% keeps a real
+        // recapture usable while a smaller overlap (e.g. a genuinely different display
+        // swapped in) still throws.
+        let rect: CGRect
+        if display.frame.contains(region.rect) {
+            rect = region.rect
+        } else {
+            let overlap = display.frame.intersection(region.rect)
+            let originalArea = region.rect.width * region.rect.height
+            let overlapArea = overlap.width * overlap.height
+            if originalArea > 0 && overlapArea / originalArea >= 0.8 {
+                rect = overlap
+            } else {
+                throw ShotdeckError.displayNoLongerConnected(displayID: region.displayID)
+            }
+        }
+
+        let localRect = CGRect(
+            x: rect.minX - display.frame.minX,
+            y: rect.minY - display.frame.minY,
+            width: rect.width,
+            height: rect.height
+        )
+
+        guard let mode = CGDisplayCopyDisplayMode(region.displayID) else {
+            throw ShotdeckError.captureFailed(
+                underlying: "no display mode for displayID \(region.displayID)"
+            )
+        }
+        guard mode.width > 0 else {
+            throw ShotdeckError.captureFailed(
+                underlying: "display mode width is 0 for displayID \(region.displayID)"
+            )
+        }
+        let scale = CGFloat(mode.pixelWidth) / CGFloat(mode.width)
+
+        let filter = SCContentFilter(display: display, excludingWindows: [])
+        let configuration = SCStreamConfiguration()
+        configuration.sourceRect = localRect
+        configuration.width = Int((localRect.width * scale).rounded())
+        configuration.height = Int((localRect.height * scale).rounded())
+        configuration.scalesToFit = false
+        configuration.showsCursor = false
+
+        let cgImage: CGImage
+        do {
+            cgImage = try await SCScreenshotManager.captureImage(
+                contentFilter: filter,
+                configuration: configuration
+            )
+        } catch {
+            throw ShotdeckError.captureFailed(underlying: error.localizedDescription)
+        }
+
+        let data = NSMutableData()
+        guard let dest = CGImageDestinationCreateWithData(
+            data,
+            UTType.png.identifier as CFString,
+            1,
+            nil
+        ) else {
+            throw ShotdeckError.captureFailed(underlying: "could not create PNG image destination")
+        }
+        CGImageDestinationAddImage(dest, cgImage, nil)
+        guard CGImageDestinationFinalize(dest) else {
+            throw ShotdeckError.captureFailed(underlying: "PNG encoding failed to finalize")
+        }
+
+        return CapturedImage(
+            pngData: data as Data,
+            pixelWidth: cgImage.width,
+            pixelHeight: cgImage.height,
+            scale: scale
+        )
+    }
+}

Sources/ShotdeckCore/Model/ShotdeckError.swift

@@ -16,7 +16,7 @@ public enum ShotdeckError: Error, LocalizedError, Sendable {
         case .screenRecordingNotGranted:
             return "Screen Recording is turned off. Grant it in System Settings to capture."
         case .noRegionRemembered:
-            return "No capture region is set. Press ⌥⇧1 to pick one."
+            return "No capture region is set. Choose 'Re-select area' from the Shotdeck menu."
         case .displayNoLongerConnected:
             return "The display used for capture is no longer connected."
         case .captureFailed(let underlying):

Sources/ShotdeckCore/PDF/PDFComposer.swift

@@ -0,0 +1,209 @@
+import AppKit
+import CoreGraphics
+import CoreText
+import Foundation
+import ImageIO
+import os
+
+private let pdfLog = Logger(subsystem: "ai.flowmaster.shotdeck", category: "PDF")
+
+public struct PDFComposer: Sendable {
+    public init() {}
+
+    @discardableResult
+    public func compose(
+        session: CaptureSession,
+        imageURL: (Capture) -> URL,
+        title: String,
+        to outputURL: URL
+    ) throws -> Int {
+        if session.isEmpty {
+            throw ShotdeckError.pdfCompositionFailed(reason: "session has no captures")
+        }
+
+        var loaded: [(Capture, CGImage)] = []
+        loaded.reserveCapacity(session.captures.count)
+        for capture in session.captures {
+            let url = imageURL(capture)
+            if let image = Self.loadCGImage(from: url) {
+                loaded.append((capture, image))
+            } else {
+                pdfLog.error(
+                    "skipping capture \(capture.id.uuidString, privacy: .public) seq \(capture.sequence, privacy: .public): image unreadable at \(url.path, privacy: .public)"
+                )
+            }
+        }
+
+        guard !loaded.isEmpty else {
+            throw ShotdeckError.pdfCompositionFailed(reason: "no readable images in session")
+        }
+
+        let pageCount = loaded.count
+        let tmpURL = outputURL
+            .deletingLastPathComponent()
+            .appendingPathComponent(".tmp-\(UUID().uuidString)-\(outputURL.lastPathComponent)")
+
+        do {
+            try Self.writePDF(
+                loaded: loaded,
+                pageCount: pageCount,
+                title: title,
+                sessionID: session.id,
+                to: tmpURL
+            )
+
+            let handle = try FileHandle(forWritingTo: tmpURL)
+            try handle.synchronize()
+            try handle.close()
+
+            if FileManager.default.fileExists(atPath: outputURL.path) {
+                try FileManager.default.removeItem(at: outputURL)
+            }
+            try FileManager.default.moveItem(at: tmpURL, to: outputURL)
+            return pageCount
+        } catch {
+            try? FileManager.default.removeItem(at: tmpURL)
+            if let shotdeck = error as? ShotdeckError {
+                throw shotdeck
+            }
+            throw ShotdeckError.pdfCompositionFailed(reason: error.localizedDescription)
+        }
+    }
+
+    public static func fileName(for session: CaptureSession) -> String {
+        "Shotdeck-\(DubaiTime.fileStamp(session.createdAt)).pdf"
+    }
+
+    private static func writePDF(
+        loaded: [(Capture, CGImage)],
+        pageCount: Int,
+        title: String,
+        sessionID: UUID,
+        to tmpURL: URL
+    ) throws {
+        guard let consumer = CGDataConsumer(url: tmpURL as CFURL) else {
+            throw ShotdeckError.pdfCompositionFailed(reason: "cannot open output location")
+        }
+
+        let auxiliaryInfo: [String: Any] = [
+            kCGPDFContextCreator as String: "Shotdeck",
+            kCGPDFContextTitle as String: title,
+            kCGPDFContextSubject as String: sessionID.uuidString.lowercased(),
+        ]
+
+        guard let context = CGContext(
+            consumer: consumer,
+            mediaBox: nil,
+            auxiliaryInfo as CFDictionary
+        ) else {
+            throw ShotdeckError.pdfCompositionFailed(reason: "cannot open output location")
+        }
+
+        let lightGrey = CGColor(gray: 0.75, alpha: 1)
+        let black = CGColor(gray: 0, alpha: 1)
+        let timestampColor = CGColor(gray: 0.45, alpha: 1)
+
+        for pageIndex in 1...pageCount {
+            let (capture, cgImage) = loaded[pageIndex - 1]
+            let layout = PageLayout(capture: capture, pageIndex: pageIndex, pageCount: pageCount)
+
+            context.beginPDFPage(Self.pageInfo(mediaBox: layout.pageRect))
+
+            context.draw(cgImage, in: layout.imageRect)
+
+            context.setStrokeColor(lightGrey)
+            context.setLineWidth(0.5)
+            context.move(to: CGPoint(x: layout.headerRect.minX, y: layout.headerRect.minY))
+            context.addLine(to: CGPoint(x: layout.headerRect.maxX, y: layout.headerRect.minY))
+            context.strokePath()
+
+            drawText(
+                layout.pageNumberText,
+                font: layout.pageNumberFont,
+                color: black,
+                at: layout.pageNumberOrigin,
+                in: context
+            )
+            drawText(
+                layout.timestampText,
+                font: layout.timestampFont,
+                color: timestampColor,
+                at: layout.timestampOrigin,
+                in: context
+            )
+            drawText(
+                "PASS",
+                font: layout.tickLabelFont,
+                color: black,
+                at: layout.passLabelOrigin,
+                in: context
+            )
+            drawText(
+                "FAIL",
+                font: layout.tickLabelFont,
+                color: black,
+                at: layout.failLabelOrigin,
+                in: context
+            )
+
+            strokeTickBox(layout.passTickBox, in: context, color: black)
+            strokeTickBox(layout.failTickBox, in: context, color: black)
+
+            context.endPDFPage()
+        }
+
+        context.closePDF()
+    }
+
+    private static func pageInfo(mediaBox: CGRect) -> CFDictionary {
+        var box = mediaBox
+        let data = Data(bytes: &box, count: MemoryLayout<CGRect>.size)
+        return [kCGPDFContextMediaBox as String: data] as CFDictionary
+    }
+
+    private static func drawText(
+        _ string: String,
+        font: NSFont,
+        color: CGColor,
+        at origin: CGPoint,
+        in context: CGContext
+    ) {
+        let attributes: [CFString: Any] = [
+            kCTFontAttributeName: font,
+            kCTForegroundColorAttributeName: color,
+        ]
+        guard let attributed = CFAttributedStringCreate(
+            nil,
+            string as CFString,
+            attributes as CFDictionary
+        ) else {
+            return
+        }
+        let line = CTLineCreateWithAttributedString(attributed)
+        context.textMatrix = .identity
+        context.textPosition = origin
+        CTLineDraw(line, context)
+    }
+
+    private static func strokeTickBox(_ box: CGRect, in context: CGContext, color: CGColor) {
+        let path = CGPath(
+            roundedRect: box,
+            cornerWidth: 2,
+            cornerHeight: 2,
+            transform: nil
+        )
+        context.addPath(path)
+        context.setStrokeColor(color)
+        context.setLineWidth(1.0)
+        context.strokePath()
+    }
+
+    private static func loadCGImage(from url: URL) -> CGImage? {
+        guard let source = CGImageSourceCreateWithURL(url as CFURL, nil),
+              CGImageSourceGetCount(source) > 0
+        else {
+            return nil
+        }
+        return CGImageSourceCreateImageAtIndex(source, 0, nil)
+    }
+}

Sources/ShotdeckCore/PDF/PageLayout.swift

@@ -0,0 +1,149 @@
+import AppKit
+import CoreGraphics
+import CoreText
+import Foundation
+
+public struct PageLayout: Sendable, Equatable {
+    public let isLandscape: Bool
+    public let pageRect: CGRect
+    public let headerRect: CGRect
+    public let imageBoxRect: CGRect
+    public let imageRect: CGRect
+
+    public let pageNumberText: String
+    public let pageNumberOrigin: CGPoint
+    public let timestampText: String
+    public let timestampOrigin: CGPoint
+
+    public let passLabelOrigin: CGPoint
+    public let failLabelOrigin: CGPoint
+    public let passTickBox: CGRect
+    public let failTickBox: CGRect
+
+    /// Constructed at access time so `PageLayout` stays Sendable under Swift 6
+    /// (`NSFont` is not Sendable). Same `NSFont.systemFont` values used for measurement.
+    public var pageNumberFont: NSFont { NSFont.systemFont(ofSize: 9, weight: .semibold) }
+    public var timestampFont: NSFont { NSFont.systemFont(ofSize: 9, weight: .regular) }
+    public var tickLabelFont: NSFont { NSFont.systemFont(ofSize: 8, weight: .semibold) }
+
+    private static let marginAll: CGFloat = 18
+    private static let headerHeight: CGFloat = 26
+    private static let headerImageGap: CGFloat = 10
+    private static let tickBoxSize: CGFloat = 13
+    private static let tickGroupGap: CGFloat = 8
+    private static let portraitPage = CGSize(width: 595, height: 842)
+    private static let landscapePage = CGSize(width: 842, height: 595)
+
+    /// `pageIndex` and `pageCount` are 1-based / total, over ACTUALLY-WRITTEN pages
+    /// (see SPEC decision D-D), not `capture.sequence` / `session.captures.count`.
+    public init(capture: Capture, pageIndex: Int, pageCount: Int) {
+        let pageNumberFont = NSFont.systemFont(ofSize: 9, weight: .semibold)
+        let timestampFont = NSFont.systemFont(ofSize: 9, weight: .regular)
+        let tickLabelFont = NSFont.systemFont(ofSize: 8, weight: .semibold)
+
+        isLandscape = capture.isLandscape
+        pageRect = CGRect(origin: .zero, size: isLandscape ? Self.landscapePage : Self.portraitPage)
+        let W = pageRect.width
+        let H = pageRect.height
+
+        let contentMinX = Self.marginAll
+        let contentMaxX = W - Self.marginAll
+        let contentMinY = Self.marginAll
+        let contentMaxY = H - Self.marginAll
+        let contentWidth = contentMaxX - contentMinX
+
+        headerRect = CGRect(
+            x: contentMinX,
+            y: contentMaxY - Self.headerHeight,
+            width: contentWidth,
+            height: Self.headerHeight
+        )
+
+        imageBoxRect = CGRect(
+            x: contentMinX,
+            y: contentMinY,
+            width: contentWidth,
+            height: headerRect.minY - Self.headerImageGap - contentMinY
+        )
+
+        let pointSize = CGSize(
+            width: CGFloat(capture.pixelWidth) / capture.scale,
+            height: CGFloat(capture.pixelHeight) / capture.scale
+        )
+        let fitScale = min(
+            imageBoxRect.width / pointSize.width,
+            imageBoxRect.height / pointSize.height,
+            1.0
+        )
+        let drawnSize = CGSize(
+            width: pointSize.width * fitScale,
+            height: pointSize.height * fitScale
+        )
+        imageRect = CGRect(
+            x: imageBoxRect.midX - drawnSize.width / 2,
+            y: imageBoxRect.midY - drawnSize.height / 2,
+            width: drawnSize.width,
+            height: drawnSize.height
+        )
+
+        let metricsFont = timestampFont as CTFont
+        let ascent = CTFontGetAscent(metricsFont)
+        let descent = CTFontGetDescent(metricsFont)
+        let baselineY = headerRect.minY + (headerRect.height - (ascent + descent)) / 2 + descent
+
+        pageNumberText = "\(pageIndex) / \(pageCount)"
+        pageNumberOrigin = CGPoint(x: headerRect.minX, y: baselineY)
+
+        timestampText = DubaiTime.stamp(capture.capturedAt)
+        let pageNumberWidth = Self.measuredWidth(pageNumberText, font: pageNumberFont)
+        timestampOrigin = CGPoint(x: headerRect.minX + pageNumberWidth + 10, y: baselineY)
+
+        let groupRightX = headerRect.maxX
+        let failBoxMinX = groupRightX - Self.tickBoxSize
+        let tickBoxY = headerRect.midY - Self.tickBoxSize / 2
+        failTickBox = CGRect(
+            x: failBoxMinX,
+            y: tickBoxY,
+            width: Self.tickBoxSize,
+            height: Self.tickBoxSize
+        )
+
+        let failLabelWidth = Self.measuredWidth("FAIL", font: tickLabelFont)
+        let failLabelMaxX = failTickBox.minX - Self.tickGroupGap
+        failLabelOrigin = CGPoint(x: failLabelMaxX - failLabelWidth, y: baselineY)
+
+        let passBoxMaxX = failLabelOrigin.x - Self.tickGroupGap
+        passTickBox = CGRect(
+            x: passBoxMaxX - Self.tickBoxSize,
+            y: tickBoxY,
+            width: Self.tickBoxSize,
+            height: Self.tickBoxSize
+        )
+
+        let passLabelWidth = Self.measuredWidth("PASS", font: tickLabelFont)
+        let passLabelMaxX = passTickBox.minX - Self.tickGroupGap
+        passLabelOrigin = CGPoint(x: passLabelMaxX - passLabelWidth, y: baselineY)
+    }
+
+    public static func == (lhs: PageLayout, rhs: PageLayout) -> Bool {
+        lhs.isLandscape == rhs.isLandscape
+            && lhs.pageRect == rhs.pageRect
+            && lhs.headerRect == rhs.headerRect
+            && lhs.imageBoxRect == rhs.imageBoxRect
+            && lhs.imageRect == rhs.imageRect
+            && lhs.pageNumberText == rhs.pageNumberText
+            && lhs.pageNumberOrigin == rhs.pageNumberOrigin
+            && lhs.timestampText == rhs.timestampText
+            && lhs.timestampOrigin == rhs.timestampOrigin
+            && lhs.passLabelOrigin == rhs.passLabelOrigin
+            && lhs.failLabelOrigin == rhs.failLabelOrigin
+            && lhs.passTickBox == rhs.passTickBox
+            && lhs.failTickBox == rhs.failTickBox
+    }
+
+    private static func measuredWidth(_ text: String, font: NSFont) -> CGFloat {
+        let attributed = NSAttributedString(string: text, attributes: [.font: font])
+        let line = CTLineCreateWithAttributedString(attributed)
+        return CGFloat(CTLineGetTypographicBounds(line, nil, nil, nil))
+    }
+}

Sources/ShotdeckCore/Support/AtomicFile.swift

@@ -0,0 +1,104 @@
+import Foundation
+import Darwin
+
+public enum AtomicFile {
+    /// Writes `data` to `url` durably: writes to `<url>.tmp` in the SAME directory as `url`,
+    /// fsyncs that file descriptor, closes it, rename()s it onto `url` (atomic same-volume
+    /// rename), then opens `url`'s containing directory and fsyncs THAT too (a rename is only
+    /// durable once its directory entry is flushed). Never uses `Data.write(to:)` — that call
+    /// does not fsync.
+    public static func write(_ data: Data, to url: URL) throws {
+        let finalPath = url.path
+        let directoryURL = url.deletingLastPathComponent()
+        let tmpURL = directoryURL.appendingPathComponent(url.lastPathComponent + ".tmp")
+        let tmpPath = tmpURL.path
+
+        // Clear a stale .tmp left by a previous crash. ENOENT (nothing to clear) is fine.
+        if unlink(tmpPath) != 0 && errno != ENOENT {
+            throw ShotdeckError.spoolWriteFailed(
+                path: finalPath,
+                underlying: "could not clear a stale temp file: \(String(cString: strerror(errno)))")
+        }
+
+        let fd = open(tmpPath, O_WRONLY | O_CREAT | O_TRUNC, 0o644)
+        guard fd >= 0 else {
+            throw ShotdeckError.spoolWriteFailed(
+                path: finalPath, underlying: "open failed: \(String(cString: strerror(errno)))")
+        }
+
+        var writeFailure: String?
+        data.withUnsafeBytes { (raw: UnsafeRawBufferPointer) in
+            var remaining = raw.count
+            var pointer = raw.baseAddress
+            while remaining > 0 {
+                let n = Darwin.write(fd, pointer, remaining)
+                if n < 0 {
+                    if errno == EINTR { continue }
+                    writeFailure = "write failed: \(String(cString: strerror(errno)))"
+                    break
+                }
+                if n == 0 { break }
+                remaining -= n
+                pointer = pointer?.advanced(by: n)
+            }
+        }
+        if let writeFailure {
+            close(fd)
+            _ = unlink(tmpPath)
+            throw ShotdeckError.spoolWriteFailed(path: finalPath, underlying: writeFailure)
+        }
+        if fsync(fd) != 0 {
+            let message = "fsync failed: \(String(cString: strerror(errno)))"
+            close(fd)
+            _ = unlink(tmpPath)
+            throw ShotdeckError.spoolWriteFailed(path: finalPath, underlying: message)
+        }
+        if close(fd) != 0 {
+            _ = unlink(tmpPath)
+            throw ShotdeckError.spoolWriteFailed(
+                path: finalPath, underlying: "close failed: \(String(cString: strerror(errno)))")
+        }
+        if rename(tmpPath, finalPath) != 0 {
+            let message = "rename failed: \(String(cString: strerror(errno)))"
+            _ = unlink(tmpPath)
+            throw ShotdeckError.spoolWriteFailed(path: finalPath, underlying: message)
+        }
+        try fsyncDirectory(at: directoryURL)
+    }
+
+    /// Encodes `value` with `JSONEncoder` (`.sortedKeys, .prettyPrinted`,
+    /// `.dateEncodingStrategy = .iso8601`) and writes it through `write(_:to:)`.
+    public static func writeJSON<T: Encodable>(_ value: T, to url: URL) throws {
+        let encoder = JSONEncoder()
+        encoder.outputFormatting = [.sortedKeys, .prettyPrinted]
+        encoder.dateEncodingStrategy = .iso8601
+        let data: Data
+        do {
+            data = try encoder.encode(value)
+        } catch {
+            throw ShotdeckError.spoolWriteFailed(
+                path: url.path, underlying: "JSON encoding failed: \(error.localizedDescription)")
+        }
+        try write(data, to: url)
+    }
+
+    /// Opens `url` (must be an existing directory) and fsyncs it. Used after any directory-
+    /// level `rename()` (moving/renaming a whole session directory) — the same durability
+    /// requirement as the internal directory-fsync inside `write(_:to:)`, exposed for callers
+    /// that rename directories themselves (SpoolStore).
+    public static func fsyncDirectory(at url: URL) throws {
+        let fd = open(url.path, O_RDONLY | O_DIRECTORY)
+        guard fd >= 0 else {
+            throw ShotdeckError.spoolWriteFailed(
+                path: url.path,
+                underlying: "could not open directory for fsync: \(String(cString: strerror(errno)))")
+        }
+        let result = fsync(fd)
+        close(fd)
+        if result != 0 {
+            throw ShotdeckError.spoolWriteFailed(
+                path: url.path,
+                underlying: "directory fsync failed: \(String(cString: strerror(errno)))")
+        }
+    }
+}

Sources/ShotdeckCore/Support/FolderSettings.swift

@@ -0,0 +1,111 @@
+import Foundation
+
+/// User-configurable overrides for the outbox (PDF send destination) and watch folder
+/// (AirDrop return), backed by UserDefaults. Shotdeck is NOT App-Sandboxed (no
+/// `com.apple.security.app-sandbox` entitlement in this build — it is a plain, unsandboxed
+/// SwiftPM executable). Security-scoped bookmarks exist to let a SANDBOXED app retain access
+/// to a user-picked file/folder outside its container across relaunches; an unsandboxed
+/// process already has the invoking user's own filesystem permissions on every launch, so a
+/// plain absolute path stored in UserDefaults is sufficient — including for a mounted network
+/// share, which resolves by path the same as any local folder for as long as it is mounted.
+public enum FolderSettings {
+    public static let outboxDefaultsKey = "ai.flowmaster.shotdeck.outbox"
+    public static let watchFolderDefaultsKey = "ai.flowmaster.shotdeck.watchFolder"
+
+    /// Raw stored path (or nil if never set / cleared). For display in Settings — does NOT
+    /// validate that the path still exists.
+    public static func storedOutboxPath(defaults: UserDefaults = .standard) -> String? {
+        defaults.string(forKey: outboxDefaultsKey)
+    }
+
+    public static func storedWatchFolderPath(defaults: UserDefaults = .standard) -> String? {
+        defaults.string(forKey: watchFolderDefaultsKey)
+    }
+
+    /// Persists a user-chosen folder as its absolute POSIX path.
+    public static func setOutbox(_ url: URL, defaults: UserDefaults = .standard) {
+        defaults.set(url.path, forKey: outboxDefaultsKey)
+    }
+
+    public static func setWatchFolder(_ url: URL, defaults: UserDefaults = .standard) {
+        defaults.set(url.path, forKey: watchFolderDefaultsKey)
+    }
+
+    /// Removes the override; resolve() falls back to the default again.
+    public static func resetOutbox(defaults: UserDefaults = .standard) {
+        defaults.removeObject(forKey: outboxDefaultsKey)
+    }
+
+    public static func resetWatchFolder(defaults: UserDefaults = .standard) {
+        defaults.removeObject(forKey: watchFolderDefaultsKey)
+    }
+
+    /// Resolves both folders. A stored override wins only if it is set AND the directory it
+    /// names still exists; otherwise falls back to the default (Desktop / Downloads). Never
+    /// throws — a missing/bad override is logged via `Log.ui` and silently replaced.
+    public static func resolve(
+        defaults: UserDefaults = .standard,
+        fileManager: FileManager = .default
+    ) -> (outbox: URL, watch: URL) {
+        let outbox = resolveOne(
+            storedPath: storedOutboxPath(defaults: defaults),
+            fallback: defaultOutbox(fileManager: fileManager),
+            label: "outbox", fileManager: fileManager)
+        let watch = resolveOne(
+            storedPath: storedWatchFolderPath(defaults: defaults),
+            fallback: defaultWatchFolder(fileManager: fileManager),
+            label: "watch", fileManager: fileManager)
+        return (outbox, watch)
+    }
+
+    /// Builds an `AppSupportPaths` using `root` (defaults to the standard
+    /// `~/Library/Application Support/Shotdeck`, computed the same way
+    /// `AppSupportPaths.standard()` does, when `root` is nil) plus whatever `resolve()`
+    /// returns for outbox/watch. This is the ONLY place that combines FolderSettings with
+    /// AppSupportPaths — call this everywhere in the app instead of `AppSupportPaths.standard()`.
+    /// `root` is exposed purely so tests can point it at a temporary directory instead of the
+    /// user's real Application Support folder.
+    public static func resolvedAppSupportPaths(
+        root: URL? = nil,
+        defaults: UserDefaults = .standard,
+        fileManager: FileManager = .default
+    ) throws -> AppSupportPaths {
+        let resolvedRoot: URL
+        if let root {
+            resolvedRoot = root
+        } else {
+            let appSupportParent = try fileManager.url(
+                for: .applicationSupportDirectory, in: .userDomainMask,
+                appropriateFor: nil, create: true)
+            resolvedRoot = appSupportParent.appendingPathComponent("Shotdeck", isDirectory: true)
+        }
+        let folders = resolve(defaults: defaults, fileManager: fileManager)
+        return try AppSupportPaths(root: resolvedRoot, outbox: folders.outbox, watchFolder: folders.watch)
+    }
+
+    private static func defaultOutbox(fileManager: FileManager) -> URL {
+        fileManager.urls(for: .desktopDirectory, in: .userDomainMask).first
+            ?? fileManager.homeDirectoryForCurrentUser.appendingPathComponent("Desktop", isDirectory: true)
+    }
+
+    private static func defaultWatchFolder(fileManager: FileManager) -> URL {
+        fileManager.urls(for: .downloadsDirectory, in: .userDomainMask).first
+            ?? fileManager.homeDirectoryForCurrentUser.appendingPathComponent("Downloads", isDirectory: true)
+    }
+
+    private static func resolveOne(
+        storedPath: String?,
+        fallback: URL,
+        label: String,
+        fileManager: FileManager
+    ) -> URL {
+        guard let storedPath else { return fallback }
+        var isDirectory: ObjCBool = false
+        let exists = fileManager.fileExists(atPath: storedPath, isDirectory: &isDirectory)
+        guard exists, isDirectory.boolValue else {
+            Log.ui.warning("Configured \(label, privacy: .public) folder \(storedPath, privacy: .public) no longer exists; falling back to the default.")
+            return fallback
+        }
+        return URL(fileURLWithPath: storedPath, isDirectory: true)
+    }
+}

Sources/ShotdeckCore/Support/Log.swift

@@ -0,0 +1,9 @@
+import os
+
+public enum Log {
+    public static let spool = Logger(subsystem: "ai.flowmaster.shotdeck", category: "spool")
+    public static let pdf = Logger(subsystem: "ai.flowmaster.shotdeck", category: "pdf")
+    public static let capture = Logger(subsystem: "ai.flowmaster.shotdeck", category: "capture")
+    public static let returns = Logger(subsystem: "ai.flowmaster.shotdeck", category: "returns")
+    public static let ui = Logger(subsystem: "ai.flowmaster.shotdeck", category: "ui")
+}

Tests/ShotdeckCoreTests/AtomicFileTests.swift

@@ -0,0 +1,178 @@
+import Foundation
+import Testing
+import ShotdeckCore
+
+@Test
+func atomicWriteProducesByteIdenticalFileAndLeavesNoTmp() throws {
+    let directory = try makeTemporaryDirectory(prefix: "shotdeck-atomic-write")
+    defer { try? FileManager.default.removeItem(at: directory) }
+
+    let url = directory.appendingPathComponent("payload.bin")
+    let data = Data("shotdeck-durable-bytes".utf8)
+
+    try AtomicFile.write(data, to: url)
+
+    let onDisk = try Data(contentsOf: url)
+    #expect(onDisk == data)
+    #expect(!FileManager.default.fileExists(atPath: url.path + ".tmp"))
+}
+
+@Test
+func atomicWriteToTheSameURLTwiceKeepsTheSecondPayload() throws {
+    let directory = try makeTemporaryDirectory(prefix: "shotdeck-atomic-rewrite")
+    defer { try? FileManager.default.removeItem(at: directory) }
+
+    let url = directory.appendingPathComponent("payload.bin")
+    let first = Data("first-pass".utf8)
+    let second = Data("second-pass-wins".utf8)
+
+    try AtomicFile.write(first, to: url)
+    try AtomicFile.write(second, to: url)
+
+    let onDisk = try Data(contentsOf: url)
+    #expect(onDisk == second)
+    #expect(!FileManager.default.fileExists(atPath: url.path + ".tmp"))
+}
+
+@Test
+func atomicWriteThrowsWhenParentDirectoryDoesNotExist() throws {
+    let missingParent = FileManager.default.temporaryDirectory
+        .appendingPathComponent("shotdeck-atomic-missing-\(UUID().uuidString)", isDirectory: true)
+    let url = missingParent.appendingPathComponent("payload.bin")
+    let data = Data("never-written".utf8)
+
+    let error = try #require(throws: ShotdeckError.self) {
+        try AtomicFile.write(data, to: url)
+    }
+    guard case .spoolWriteFailed(let path, _) = error else {
+        Issue.record("expected spoolWriteFailed, got \(error)")
+        return
+    }
+    #expect(path == url.path)
+    #expect(!FileManager.default.fileExists(atPath: url.path))
+}
+
+@Test
+func atomicWriteClearsAStaleTmpAndWritesTheNewPayload() throws {
+    let directory = try makeTemporaryDirectory(prefix: "shotdeck-atomic-stale-tmp")
+    defer { try? FileManager.default.removeItem(at: directory) }
+
+    let url = directory.appendingPathComponent("payload.bin")
+    let tmpURL = directory.appendingPathComponent(url.lastPathComponent + ".tmp")
+    let garbage = Data("stale-crash-garbage".utf8)
+    let newData = Data("recovered-payload".utf8)
+
+    try garbage.write(to: tmpURL)
+    #expect(FileManager.default.fileExists(atPath: tmpURL.path))
+
+    try AtomicFile.write(newData, to: url)
+
+    let onDisk = try Data(contentsOf: url)
+    #expect(onDisk == newData)
+    #expect(!FileManager.default.fileExists(atPath: tmpURL.path))
+}
+
+@Test
+func writeJSONSortsKeysPrettyPrintsAndEncodesDatesAsISO8601() throws {
+    let directory = try makeTemporaryDirectory(prefix: "shotdeck-atomic-json-format")
+    defer { try? FileManager.default.removeItem(at: directory) }
+
+    let url = directory.appendingPathComponent("session.json")
+    let date = try iso8601Date(year: 2026, month: 8, day: 30, hour: 9, minute: 42, second: 5)
+    let value = JSONProbe(zebra: "last", apple: 7, capturedAt: date)
+
+    try AtomicFile.writeJSON(value, to: url)
+
+    let raw = try Data(contentsOf: url)
+    let text = try #require(String(data: raw, encoding: .utf8))
+
+    let apple = try #require(text.range(of: "\"apple\""))
+    let capturedAt = try #require(text.range(of: "\"capturedAt\""))
+    let zebra = try #require(text.range(of: "\"zebra\""))
+    #expect(apple.lowerBound < capturedAt.lowerBound)
+    #expect(capturedAt.lowerBound < zebra.lowerBound)
+    #expect(text.contains("\n"))
+    #expect(text.contains("  \"apple\""))
+    #expect(text.contains("2026-08-30T09:42:05Z"))
+    #expect(!text.contains("\(date.timeIntervalSinceReferenceDate)"))
+    #expect(!FileManager.default.fileExists(atPath: url.path + ".tmp"))
+}
+
+@Test
+func writeJSONRoundTripsThroughISO8601Decoder() throws {
+    let directory = try makeTemporaryDirectory(prefix: "shotdeck-atomic-json-roundtrip")
+    defer { try? FileManager.default.removeItem(at: directory) }
+
+    let url = directory.appendingPathComponent("session.json")
+    let date = try iso8601Date(year: 2026, month: 8, day: 31, hour: 13, minute: 5, second: 9)
+    let original = JSONProbe(zebra: "keep", apple: 42, capturedAt: date)
+
+    try AtomicFile.writeJSON(original, to: url)
+
+    let decoder = JSONDecoder()
+    decoder.dateDecodingStrategy = .iso8601
+    let decoded = try decoder.decode(JSONProbe.self, from: Data(contentsOf: url))
+    #expect(decoded == original)
+}
+
+@Test
+func fsyncDirectorySucceedsOnADirectoryAndThrowsOnMissingOrFilePaths() throws {
+    let directory = try makeTemporaryDirectory(prefix: "shotdeck-atomic-fsync-dir")
+    defer { try? FileManager.default.removeItem(at: directory) }
+
+    try AtomicFile.fsyncDirectory(at: directory)
+
+    let missing = directory.appendingPathComponent("does-not-exist", isDirectory: true)
+    let missingError = try #require(throws: ShotdeckError.self) {
+        try AtomicFile.fsyncDirectory(at: missing)
+    }
+    guard case .spoolWriteFailed = missingError else {
+        Issue.record("expected spoolWriteFailed for a missing path, got \(missingError)")
+        return
+    }
+
+    let fileURL = directory.appendingPathComponent("not-a-directory.bin")
+    try AtomicFile.write(Data("file".utf8), to: fileURL)
+    let fileError = try #require(throws: ShotdeckError.self) {
+        try AtomicFile.fsyncDirectory(at: fileURL)
+    }
+    guard case .spoolWriteFailed = fileError else {
+        Issue.record("expected spoolWriteFailed for a file path, got \(fileError)")
+        return
+    }
+}
+
+private struct JSONProbe: Codable, Equatable {
+    var zebra: String
+    var apple: Int
+    var capturedAt: Date
+}
+
+private func makeTemporaryDirectory(prefix: String) throws -> URL {
+    let url = FileManager.default.temporaryDirectory
+        .appendingPathComponent("\(prefix)-\(UUID().uuidString)", isDirectory: true)
+    try FileManager.default.createDirectory(at: url, withIntermediateDirectories: true)
+    return url
+}
+
+private func iso8601Date(
+    year: Int,
+    month: Int,
+    day: Int,
+    hour: Int,
+    minute: Int,
+    second: Int
+) throws -> Date {
+    var calendar = Calendar(identifier: .gregorian)
+    calendar.timeZone = try #require(TimeZone(secondsFromGMT: 0))
+    return try #require(
+        calendar.date(from: DateComponents(
+            year: year,
+            month: month,
+            day: day,
+            hour: hour,
+            minute: minute,
+            second: second
+        ))
+    )
+}

Tests/ShotdeckCoreTests/FolderSettingsTests.swift

@@ -0,0 +1,168 @@
+import Foundation
+import Testing
+import ShotdeckCore
+
+@Test
+func resolveWithoutStoredKeysReturnsDesktopAndDownloads() throws {
+    let suite = try makeDefaultsSuite()
+    defer { tearDown(suite) }
+
+    let resolved = FolderSettings.resolve(defaults: suite.defaults)
+    let expectedOutbox = try #require(
+        FileManager.default.urls(for: .desktopDirectory, in: .userDomainMask).first
+    )
+    let expectedWatch = try #require(
+        FileManager.default.urls(for: .downloadsDirectory, in: .userDomainMask).first
+    )
+
+    #expect(resolved.outbox.path == expectedOutbox.path)
+    #expect(resolved.watch.path == expectedWatch.path)
+}
+
+@Test
+func setOutboxToAnExistingDirectoryIsReturnedByResolve() throws {
+    let suite = try makeDefaultsSuite()
+    defer { tearDown(suite) }
+    let outbox = try makeTemporaryDirectory(prefix: "shotdeck-outbox-set")
+    defer { try? FileManager.default.removeItem(at: outbox) }
+
+    FolderSettings.setOutbox(outbox, defaults: suite.defaults)
+    let resolved = FolderSettings.resolve(defaults: suite.defaults)
+    let expectedWatch = try #require(
+        FileManager.default.urls(for: .downloadsDirectory, in: .userDomainMask).first
+    )
+
+    #expect(resolved.outbox.path == outbox.path)
+    #expect(resolved.watch.path == expectedWatch.path)
+    #expect(FolderSettings.storedOutboxPath(defaults: suite.defaults) == outbox.path)
+}
+
+@Test
+func resolveFallsBackWhenTheStoredOutboxDirectoryIsGone() throws {
+    let suite = try makeDefaultsSuite()
+    defer { tearDown(suite) }
+    let outbox = try makeTemporaryDirectory(prefix: "shotdeck-outbox-gone")
+
+    FolderSettings.setOutbox(outbox, defaults: suite.defaults)
+    try FileManager.default.removeItem(at: outbox)
+
+    let resolved = FolderSettings.resolve(defaults: suite.defaults)
+    let expectedOutbox = try #require(
+        FileManager.default.urls(for: .desktopDirectory, in: .userDomainMask).first
+    )
+    #expect(resolved.outbox.path == expectedOutbox.path)
+}
+
+@Test
+func setWatchFolderMirrorsOutboxOverrideAndFallbackIndependently() throws {
+    let suite = try makeDefaultsSuite()
+    defer { tearDown(suite) }
+    let watch = try makeTemporaryDirectory(prefix: "shotdeck-watch-set")
+    let expectedOutbox = try #require(
+        FileManager.default.urls(for: .desktopDirectory, in: .userDomainMask).first
+    )
+
+    FolderSettings.setWatchFolder(watch, defaults: suite.defaults)
+    let withOverride = FolderSettings.resolve(defaults: suite.defaults)
+    #expect(withOverride.watch.path == watch.path)
+    #expect(withOverride.outbox.path == expectedOutbox.path)
+
+    try FileManager.default.removeItem(at: watch)
+    let afterDelete = FolderSettings.resolve(defaults: suite.defaults)
+    let expectedWatch = try #require(
+        FileManager.default.urls(for: .downloadsDirectory, in: .userDomainMask).first
+    )
+    #expect(afterDelete.watch.path == expectedWatch.path)
+    #expect(afterDelete.outbox.path == expectedOutbox.path)
+}
+
+@Test
+func resetOutboxClearsTheOverride() throws {
+    let suite = try makeDefaultsSuite()
+    defer { tearDown(suite) }
+    let outbox = try makeTemporaryDirectory(prefix: "shotdeck-outbox-reset")
+    defer { try? FileManager.default.removeItem(at: outbox) }
+
+    FolderSettings.setOutbox(outbox, defaults: suite.defaults)
+    FolderSettings.resetOutbox(defaults: suite.defaults)
+
+    let resolved = FolderSettings.resolve(defaults: suite.defaults)
+    let expectedOutbox = try #require(
+        FileManager.default.urls(for: .desktopDirectory, in: .userDomainMask).first
+    )
+    #expect(resolved.outbox.path == expectedOutbox.path)
+    #expect(FolderSettings.storedOutboxPath(defaults: suite.defaults) == nil)
+}
+
+@Test
+func resolvedAppSupportPathsUsesTheOutboxOverrideAndCreatesSpoolArchive() throws {
+    let suite = try makeDefaultsSuite()
+    defer { tearDown(suite) }
+    let root = try makeTemporaryDirectory(prefix: "shotdeck-paths-root")
+    let outbox = try makeTemporaryDirectory(prefix: "shotdeck-paths-outbox")
+    defer {
+        try? FileManager.default.removeItem(at: root)
+        try? FileManager.default.removeItem(at: outbox)
+    }
+
+    FolderSettings.setOutbox(outbox, defaults: suite.defaults)
+    let paths = try FolderSettings.resolvedAppSupportPaths(root: root, defaults: suite.defaults)
+
+    #expect(paths.outbox.path == outbox.path)
+    #expect(directoryExists(paths.spool))
+    #expect(directoryExists(paths.archive))
+    #expect(paths.spool.deletingLastPathComponent().path == root.path)
+    #expect(paths.archive.deletingLastPathComponent().path == root.path)
+}
+
+@Test
+func userDefaultsSuitesDoNotLeakFolderOverrides() throws {
+    let suiteA = try makeDefaultsSuite()
+    let suiteB = try makeDefaultsSuite()
+    defer {
+        tearDown(suiteA)
+        tearDown(suiteB)
+    }
+    let outbox = try makeTemporaryDirectory(prefix: "shotdeck-suite-a-outbox")
+    defer { try? FileManager.default.removeItem(at: outbox) }
+
+    FolderSettings.setOutbox(outbox, defaults: suiteA.defaults)
+
+    let resolvedA = FolderSettings.resolve(defaults: suiteA.defaults)
+    let resolvedB = FolderSettings.resolve(defaults: suiteB.defaults)
+    let expectedOutbox = try #require(
+        FileManager.default.urls(for: .desktopDirectory, in: .userDomainMask).first
+    )
+
+    #expect(resolvedA.outbox.path == outbox.path)
+    #expect(resolvedB.outbox.path == expectedOutbox.path)
+}
+
+private struct DefaultsSuite {
+    let name: String
+    let defaults: UserDefaults
+}
+
+private func makeDefaultsSuite() throws -> DefaultsSuite {
+    let name = "shotdeck-test-\(UUID().uuidString)"
+    let defaults = try #require(UserDefaults(suiteName: name))
+    defaults.removePersistentDomain(forName: name)
+    return DefaultsSuite(name: name, defaults: defaults)
+}
+
+private func tearDown(_ suite: DefaultsSuite) {
+    suite.defaults.removePersistentDomain(forName: suite.name)
+}
+
+private func makeTemporaryDirectory(prefix: String) throws -> URL {
+    let url = FileManager.default.temporaryDirectory
+        .appendingPathComponent("\(prefix)-\(UUID().uuidString)", isDirectory: true)
+    try FileManager.default.createDirectory(at: url, withIntermediateDirectories: true)
+    return url
+}
+
+private func directoryExists(_ url: URL) -> Bool {
+    var isDirectory: ObjCBool = false
+    let exists = FileManager.default.fileExists(atPath: url.path, isDirectory: &isDirectory)
+    return exists && isDirectory.boolValue
+}

Tests/ShotdeckCoreTests/PDFComposerTests.swift

@@ -0,0 +1,579 @@
+import CoreGraphics
+import Foundation
+import ImageIO
+import PDFKit
+import ShotdeckCore
+import Testing
+import UniformTypeIdentifiers
+
+enum TestFixtureError: Error { case cannotCreateBitmap, cannotCreatePNG, cannotFinalizePNG }
+
+func writeSolidPNG(
+    pixelWidth: Int,
+    pixelHeight: Int,
+    red: UInt8,
+    green: UInt8,
+    blue: UInt8,
+    to url: URL
+) throws {
+    let colorSpace = CGColorSpaceCreateDeviceRGB()
+    guard let context = CGContext(
+        data: nil,
+        width: pixelWidth,
+        height: pixelHeight,
+        bitsPerComponent: 8,
+        bytesPerRow: pixelWidth * 4,
+        space: colorSpace,
+        bitmapInfo: CGImageAlphaInfo.premultipliedLast.rawValue
+    ) else { throw TestFixtureError.cannotCreateBitmap }
+    context.setFillColor(CGColor(
+        red: CGFloat(red) / 255,
+        green: CGFloat(green) / 255,
+        blue: CGFloat(blue) / 255,
+        alpha: 1
+    ))
+    context.fill(CGRect(x: 0, y: 0, width: pixelWidth, height: pixelHeight))
+    guard let image = context.makeImage(),
+          let destination = CGImageDestinationCreateWithURL(
+              url as CFURL,
+              UTType.png.identifier as CFString,
+              1,
+              nil
+          )
+    else { throw TestFixtureError.cannotCreatePNG }
+    CGImageDestinationAddImage(destination, image, nil)
+    guard CGImageDestinationFinalize(destination) else { throw TestFixtureError.cannotFinalizePNG }
+}
+
+private let fixtureDate = Date(timeIntervalSince1970: 1_777_482_180)
+
+private func makeCapture(
+    sequence: Int,
+    pixelWidth: Int,
+    pixelHeight: Int,
+    scale: CGFloat = 1,
+    capturedAt: Date = fixtureDate,
+    id: UUID = UUID(),
+    fileName: String? = nil
+) -> Capture {
+    Capture(
+        id: id,
+        sequence: sequence,
+        fileName: fileName ?? String(format: "%03d.png", sequence),
+        pixelWidth: pixelWidth,
+        pixelHeight: pixelHeight,
+        scale: scale,
+        capturedAt: capturedAt
+    )
+}
+
+private func makeSession(
+    captures: [Capture],
+    id: UUID = UUID(),
+    createdAt: Date = fixtureDate
+) -> CaptureSession {
+    CaptureSession(
+        id: id,
+        createdAt: createdAt,
+        state: .open,
+        captures: captures,
+        pdfFileName: nil
+    )
+}
+
+private func makeScratchDirectory() throws -> URL {
+    let url = FileManager.default.temporaryDirectory
+        .appendingPathComponent("shotdeck-pdf-\(UUID().uuidString)", isDirectory: true)
+    try FileManager.default.createDirectory(at: url, withIntermediateDirectories: true)
+    return url
+}
+
+private func writePNG(
+    for capture: Capture,
+    red: UInt8,
+    green: UInt8,
+    blue: UInt8,
+    in directory: URL
+) throws -> URL {
+    let url = directory.appendingPathComponent(capture.fileName)
+    try writeSolidPNG(
+        pixelWidth: capture.pixelWidth,
+        pixelHeight: capture.pixelHeight,
+        red: red,
+        green: green,
+        blue: blue,
+        to: url
+    )
+    return url
+}
+
+private func imageURLMap(_ urls: [UUID: URL]) -> (Capture) -> URL {
+    { capture in
+        urls[capture.id] ?? URL(fileURLWithPath: "/nonexistent/\(capture.id.uuidString).png")
+    }
+}
+
+private func openDocument(_ url: URL) throws -> PDFDocument {
+    let document = try #require(PDFDocument(url: url))
+    return document
+}
+
+private func pdftoppm(pdf: URL, prefix: URL) throws {
+    let process = Process()
+    process.executableURL = URL(fileURLWithPath: "/opt/homebrew/bin/pdftoppm")
+    process.arguments = ["-png", "-r", "110", pdf.path, prefix.path]
+    let err = Pipe()
+    process.standardError = err
+    try process.run()
+    process.waitUntilExit()
+    guard process.terminationStatus == 0 else {
+        let message = String(data: err.fileHandleForReading.readDataToEndOfFile(), encoding: .utf8) ?? ""
+        throw ShotdeckError.pdfCompositionFailed(reason: "pdftoppm failed: \(message)")
+    }
+}
+
+private struct RGBABitmap {
+    let width: Int
+    let height: Int
+    let bytesPerRow: Int
+    let data: Data
+
+    func pixel(x: Int, y: Int) -> (UInt8, UInt8, UInt8)? {
+        guard x >= 0, y >= 0, x < width, y < height else { return nil }
+        let offset = y * bytesPerRow + x * 4
+        guard offset + 2 < data.count else { return nil }
+        return (data[offset], data[offset + 1], data[offset + 2])
+    }
+
+    func containsNonWhite(x0: Int, y0: Int, x1: Int, y1: Int) -> Bool {
+        let xStart = max(0, x0)
+        let yStart = max(0, y0)
+        let xEnd = min(width, x1)
+        let yEnd = min(height, y1)
+        guard xStart < xEnd, yStart < yEnd else { return false }
+        for y in yStart..<yEnd {
+            for x in xStart..<xEnd {
+                if let (r, g, b) = pixel(x: x, y: y), r != 255 || g != 255 || b != 255 {
+                    return true
+                }
+            }
+        }
+        return false
+    }
+
+    static func loadPNG(at url: URL) throws -> RGBABitmap {
+        let colorSpace = CGColorSpaceCreateDeviceRGB()
+        let source = try #require(CGImageSourceCreateWithURL(url as CFURL, nil))
+        let image = try #require(CGImageSourceCreateImageAtIndex(source, 0, nil))
+        let width = image.width
+        let height = image.height
+        let bytesPerRow = width * 4
+        var data = Data(count: bytesPerRow * height)
+        try data.withUnsafeMutableBytes { raw in
+            guard let base = raw.baseAddress else {
+                throw TestFixtureError.cannotCreateBitmap
+            }
+            guard let context = CGContext(
+                data: base,
+                width: width,
+                height: height,
+                bitsPerComponent: 8,
+                bytesPerRow: bytesPerRow,
+                space: colorSpace,
+                bitmapInfo: CGImageAlphaInfo.premultipliedLast.rawValue
+            ) else {
+                throw TestFixtureError.cannotCreateBitmap
+            }
+            context.interpolationQuality = .none
+            context.draw(image, in: CGRect(x: 0, y: 0, width: width, height: height))
+        }
+        return RGBABitmap(width: width, height: height, bytesPerRow: bytesPerRow, data: data)
+    }
+}
+
+private func pixelWindow(
+    for rect: CGRect,
+    pageHeightPt: CGFloat,
+    scale k: CGFloat
+) -> (x0: Int, y0: Int, x1: Int, y1: Int) {
+    let pixelX0 = Int(floor(rect.minX * k))
+    let pixelX1 = Int(ceil(rect.maxX * k))
+    let pixelY0 = Int(floor((pageHeightPt - rect.maxY) * k))
+    let pixelY1 = Int(ceil((pageHeightPt - rect.minY) * k))
+    return (pixelX0, pixelY0, pixelX1, pixelY1)
+}
+
+@Test("Three-page basic compose")
+func threePageBasicCompose() throws {
+    let directory = try makeScratchDirectory()
+    defer { try? FileManager.default.removeItem(at: directory) }
+
+    let c1 = makeCapture(sequence: 1, pixelWidth: 1600, pixelHeight: 900)
+    let c2 = makeCapture(sequence: 2, pixelWidth: 900, pixelHeight: 1600)
+    let c3 = makeCapture(sequence: 3, pixelWidth: 1200, pixelHeight: 800)
+    let urls: [UUID: URL] = [
+        c1.id: try writePNG(for: c1, red: 200, green: 20, blue: 20, in: directory),
+        c2.id: try writePNG(for: c2, red: 20, green: 200, blue: 20, in: directory),
+        c3.id: try writePNG(for: c3, red: 20, green: 20, blue: 200, in: directory),
+    ]
+    let session = makeSession(captures: [c1, c2, c3])
+    let output = directory.appendingPathComponent("three.pdf")
+    let pageCount = try PDFComposer().compose(
+        session: session,
+        imageURL: imageURLMap(urls),
+        title: "Three page",
+        to: output
+    )
+    #expect(pageCount == 3)
+    let document = try openDocument(output)
+    #expect(document.pageCount == 3)
+    let p0 = try #require(document.page(at: 0))
+    let p1 = try #require(document.page(at: 1))
+    let p2 = try #require(document.page(at: 2))
+    #expect(p0.bounds(for: .mediaBox) == CGRect(x: 0, y: 0, width: 842, height: 595))
+    #expect(p1.bounds(for: .mediaBox) == CGRect(x: 0, y: 0, width: 595, height: 842))
+    #expect(p2.bounds(for: .mediaBox) == CGRect(x: 0, y: 0, width: 842, height: 595))
+}
+
+@Test("Wide/tall page geometry exact")
+func wideTallPageGeometryExact() throws {
+    let directory = try makeScratchDirectory()
+    defer { try? FileManager.default.removeItem(at: directory) }
+
+    let wide = makeCapture(sequence: 1, pixelWidth: 1600, pixelHeight: 900)
+    let tall = makeCapture(sequence: 1, pixelWidth: 900, pixelHeight: 1600)
+    let wideURL = try writePNG(for: wide, red: 10, green: 10, blue: 10, in: directory)
+    let tallURL = try writePNG(for: tall, red: 10, green: 10, blue: 10, in: directory)
+
+    let wideOut = directory.appendingPathComponent("wide.pdf")
+    _ = try PDFComposer().compose(
+        session: makeSession(captures: [wide]),
+        imageURL: { _ in wideURL },
+        title: "Wide",
+        to: wideOut
+    )
+    let tallOut = directory.appendingPathComponent("tall.pdf")
+    _ = try PDFComposer().compose(
+        session: makeSession(captures: [tall]),
+        imageURL: { _ in tallURL },
+        title: "Tall",
+        to: tallOut
+    )
+
+    let widePage = try #require(openDocument(wideOut).page(at: 0))
+    let tallPage = try #require(openDocument(tallOut).page(at: 0))
+    #expect(widePage.bounds(for: .mediaBox) == CGRect(x: 0, y: 0, width: 842, height: 595))
+    #expect(tallPage.bounds(for: .mediaBox) == CGRect(x: 0, y: 0, width: 595, height: 842))
+}
+
+@Test("Square resolves to portrait (Capture.swift:39-42 isLandscape strict >)")
+func squareResolvesToPortrait() throws {
+    let directory = try makeScratchDirectory()
+    defer { try? FileManager.default.removeItem(at: directory) }
+
+    let square = makeCapture(sequence: 1, pixelWidth: 1000, pixelHeight: 1000)
+    let png = try writePNG(for: square, red: 80, green: 80, blue: 80, in: directory)
+    let output = directory.appendingPathComponent("square.pdf")
+    _ = try PDFComposer().compose(
+        session: makeSession(captures: [square]),
+        imageURL: { _ in png },
+        title: "Square",
+        to: output
+    )
+    let page = try #require(openDocument(output).page(at: 0))
+    #expect(page.bounds(for: .mediaBox) == CGRect(x: 0, y: 0, width: 595, height: 842))
+}
+
+@Test("Retina capture uses point size, not pixel size")
+func retinaCaptureUsesPointSize() throws {
+    let capture = makeCapture(sequence: 1, pixelWidth: 2880, pixelHeight: 1620, scale: 2.0)
+    let layout = PageLayout(capture: capture, pageIndex: 1, pageCount: 1)
+    let expectedScale = min(806.0 / 1440.0, 523.0 / 810.0, 1.0)
+    let expected = CGSize(width: 1440.0 * expectedScale, height: 810.0 * expectedScale)
+    #expect(abs(layout.imageRect.width - expected.width) < 0.01)
+    #expect(abs(layout.imageRect.height - expected.height) < 0.01)
+    #expect(layout.imageRect.width < 2000)
+    #expect(layout.isLandscape)
+}
+
+@Test("Zero PDFAnnotation objects on every page")
+func zeroPDFAnnotationObjects() throws {
+    let directory = try makeScratchDirectory()
+    defer { try? FileManager.default.removeItem(at: directory) }
+
+    let c1 = makeCapture(sequence: 1, pixelWidth: 800, pixelHeight: 600)
+    let c2 = makeCapture(sequence: 2, pixelWidth: 600, pixelHeight: 800)
+    let c3 = makeCapture(sequence: 3, pixelWidth: 1000, pixelHeight: 1000)
+    let urls: [UUID: URL] = [
+        c1.id: try writePNG(for: c1, red: 30, green: 30, blue: 30, in: directory),
+        c2.id: try writePNG(for: c2, red: 40, green: 40, blue: 40, in: directory),
+        c3.id: try writePNG(for: c3, red: 50, green: 50, blue: 50, in: directory),
+    ]
+    let output = directory.appendingPathComponent("no-annots.pdf")
+    _ = try PDFComposer().compose(
+        session: makeSession(captures: [c1, c2, c3]),
+        imageURL: imageURLMap(urls),
+        title: "No annotations",
+        to: output
+    )
+    let document = try openDocument(output)
+    #expect(document.pageCount == 3)
+    for index in 0..<document.pageCount {
+        let page = try #require(document.page(at: index))
+        #expect(page.annotations.isEmpty)
+    }
+}
+
+@Test("Mixed orientations coexist, unnormalised")
+func mixedOrientationsCoexist() throws {
+    let directory = try makeScratchDirectory()
+    defer { try? FileManager.default.removeItem(at: directory) }
+
+    let wide = makeCapture(sequence: 1, pixelWidth: 1600, pixelHeight: 900)
+    let tall = makeCapture(sequence: 2, pixelWidth: 900, pixelHeight: 1600)
+    let square = makeCapture(sequence: 3, pixelWidth: 1000, pixelHeight: 1000)
+    let urls: [UUID: URL] = [
+        wide.id: try writePNG(for: wide, red: 90, green: 10, blue: 10, in: directory),
+        tall.id: try writePNG(for: tall, red: 10, green: 90, blue: 10, in: directory),
+        square.id: try writePNG(for: square, red: 10, green: 10, blue: 90, in: directory),
+    ]
+    let output = directory.appendingPathComponent("mixed.pdf")
+    _ = try PDFComposer().compose(
+        session: makeSession(captures: [wide, tall, square]),
+        imageURL: imageURLMap(urls),
+        title: "Mixed",
+        to: output
+    )
+    let document = try openDocument(output)
+    #expect(document.pageCount == 3)
+    let p0 = try #require(document.page(at: 0))
+    let p1 = try #require(document.page(at: 1))
+    let p2 = try #require(document.page(at: 2))
+    #expect(p0.bounds(for: .mediaBox) == CGRect(x: 0, y: 0, width: 842, height: 595))
+    #expect(p1.bounds(for: .mediaBox) == CGRect(x: 0, y: 0, width: 595, height: 842))
+    #expect(p2.bounds(for: .mediaBox) == CGRect(x: 0, y: 0, width: 595, height: 842))
+}
+
+@Test("No cover page, no before/after, exactly one page per capture")
+func noCoverPageExactlyOnePagePerCapture() throws {
+    let directory = try makeScratchDirectory()
+    defer { try? FileManager.default.removeItem(at: directory) }
+
+    let c1 = makeCapture(sequence: 1, pixelWidth: 800, pixelHeight: 500)
+    let c2 = makeCapture(sequence: 2, pixelWidth: 500, pixelHeight: 800)
+    let urls: [UUID: URL] = [
+        c1.id: try writePNG(for: c1, red: 12, green: 12, blue: 12, in: directory),
+        c2.id: try writePNG(for: c2, red: 22, green: 22, blue: 22, in: directory),
+    ]
+    let output = directory.appendingPathComponent("two.pdf")
+    let pageCount = try PDFComposer().compose(
+        session: makeSession(captures: [c1, c2]),
+        imageURL: imageURLMap(urls),
+        title: "Two",
+        to: output
+    )
+    #expect(pageCount == 2)
+    #expect(try openDocument(output).pageCount == 2)
+}
+
+@Test("Small image is never upscaled")
+func smallImageIsNeverUpscaled() throws {
+    let capture = makeCapture(sequence: 1, pixelWidth: 200, pixelHeight: 150)
+    let layout = PageLayout(capture: capture, pageIndex: 1, pageCount: 1)
+    #expect(layout.imageRect.size == CGSize(width: 200, height: 150))
+}
+
+@Test("Empty session throws, produces nothing on disk")
+func emptySessionThrowsProducesNothing() throws {
+    let directory = try makeScratchDirectory()
+    defer { try? FileManager.default.removeItem(at: directory) }
+
+    let output = directory.appendingPathComponent("empty.pdf")
+    var threwCompositionFailed = false
+    do {
+        _ = try PDFComposer().compose(
+            session: makeSession(captures: []),
+            imageURL: { _ in directory.appendingPathComponent("missing.png") },
+            title: "Empty",
+            to: output
+        )
+    } catch ShotdeckError.pdfCompositionFailed {
+        threwCompositionFailed = true
+    }
+    #expect(threwCompositionFailed)
+    #expect(!FileManager.default.fileExists(atPath: output.path))
+    let leftover = try FileManager.default.contentsOfDirectory(atPath: directory.path)
+    #expect(leftover.isEmpty)
+}
+
+@Test("A missing PNG is skipped, page count drops, document still opens")
+func missingPNGIsSkipped() throws {
+    let directory = try makeScratchDirectory()
+    defer { try? FileManager.default.removeItem(at: directory) }
+
+    let first = makeCapture(sequence: 1, pixelWidth: 1600, pixelHeight: 900)
+    let missing = makeCapture(sequence: 2, pixelWidth: 800, pixelHeight: 600)
+    let third = makeCapture(sequence: 3, pixelWidth: 900, pixelHeight: 1600)
+    let firstURL = try writePNG(for: first, red: 220, green: 10, blue: 10, in: directory)
+    let thirdURL = try writePNG(for: third, red: 10, green: 10, blue: 220, in: directory)
+    let missingURL = directory.appendingPathComponent("does-not-exist.png")
+    let urls: [UUID: URL] = [
+        first.id: firstURL,
+        missing.id: missingURL,
+        third.id: thirdURL,
+    ]
+    let output = directory.appendingPathComponent("skip-missing.pdf")
+    let pageCount = try PDFComposer().compose(
+        session: makeSession(captures: [first, missing, third]),
+        imageURL: imageURLMap(urls),
+        title: "Skip missing",
+        to: output
+    )
+    #expect(pageCount == 2)
+    let document = try openDocument(output)
+    #expect(document.pageCount == 2)
+    let p0 = try #require(document.page(at: 0))
+    let p1 = try #require(document.page(at: 1))
+    #expect(p0.bounds(for: .mediaBox) == CGRect(x: 0, y: 0, width: 842, height: 595))
+    #expect(p1.bounds(for: .mediaBox) == CGRect(x: 0, y: 0, width: 595, height: 842))
+
+    // Distinct fill colors sampled from pdftoppm at each imageRect center.
+    let prefix = directory.appendingPathComponent("skip-missing")
+    try pdftoppm(pdf: output, prefix: prefix)
+    let page1PNG = directory.appendingPathComponent("skip-missing-1.png")
+    let page2PNG = directory.appendingPathComponent("skip-missing-2.png")
+    let bitmap1 = try RGBABitmap.loadPNG(at: page1PNG)
+    let bitmap2 = try RGBABitmap.loadPNG(at: page2PNG)
+    let k = 110.0 / 72.0
+    let layout1 = PageLayout(capture: first, pageIndex: 1, pageCount: 2)
+    let layout2 = PageLayout(capture: third, pageIndex: 2, pageCount: 2)
+    let c1 = try #require(bitmap1.pixel(
+        x: Int((layout1.imageRect.midX * k).rounded()),
+        y: Int(((layout1.pageRect.height - layout1.imageRect.midY) * k).rounded())
+    ))
+    let c2 = try #require(bitmap2.pixel(
+        x: Int((layout2.imageRect.midX * k).rounded()),
+        y: Int(((layout2.pageRect.height - layout2.imageRect.midY) * k).rounded())
+    ))
+    #expect(c1.0 > 150 && c1.1 < 80 && c1.2 < 80)
+    #expect(c2.2 > 150 && c2.0 < 80 && c2.1 < 80)
+}
+
+@Test("An unreadable (corrupt) PNG is treated exactly like a missing one (D-A)")
+func unreadablePNGIsSkippedLikeMissing() throws {
+    let directory = try makeScratchDirectory()
+    defer { try? FileManager.default.removeItem(at: directory) }
+
+    let good = makeCapture(sequence: 1, pixelWidth: 800, pixelHeight: 500)
+    let bad = makeCapture(sequence: 2, pixelWidth: 800, pixelHeight: 500)
+    let goodURL = try writePNG(for: good, red: 30, green: 140, blue: 30, in: directory)
+    let badURL = directory.appendingPathComponent("corrupt.png")
+    try Data([0x00, 0x01, 0x02, 0xFF, 0xD8, 0x00]).write(to: badURL)
+    let urls: [UUID: URL] = [good.id: goodURL, bad.id: badURL]
+    let output = directory.appendingPathComponent("skip-corrupt.pdf")
+    let pageCount = try PDFComposer().compose(
+        session: makeSession(captures: [good, bad]),
+        imageURL: imageURLMap(urls),
+        title: "Skip corrupt",
+        to: output
+    )
+    #expect(pageCount == 1)
+    let document = try openDocument(output)
+    #expect(document.pageCount == 1)
+}
+
+@Test("Document attributes round-trip exactly")
+func documentAttributesRoundTrip() throws {
+    let directory = try makeScratchDirectory()
+    defer { try? FileManager.default.removeItem(at: directory) }
+
+    let sessionID = try #require(UUID(uuidString: "deadbeef-dead-4eef-8ead-deadbeef0001"))
+    let capture = makeCapture(sequence: 1, pixelWidth: 640, pixelHeight: 480)
+    let png = try writePNG(for: capture, red: 40, green: 40, blue: 40, in: directory)
+    let output = directory.appendingPathComponent("attrs.pdf")
+    _ = try PDFComposer().compose(
+        session: makeSession(captures: [capture], id: sessionID),
+        imageURL: { _ in png },
+        title: "Ben review — 2026-08-30",
+        to: output
+    )
+    let document = try openDocument(output)
+    let attributes = try #require(document.documentAttributes)
+    #expect(attributes[PDFDocumentAttribute.creatorAttribute] as? String == "Shotdeck")
+    #expect(attributes[PDFDocumentAttribute.titleAttribute] as? String == "Ben review — 2026-08-30")
+    #expect(attributes[PDFDocumentAttribute.subjectAttribute] as? String == "deadbeef-dead-4eef-8ead-deadbeef0001")
+    #expect(document.pageCount == 1)
+    #expect(try #require(document.page(at: 0)).annotations.isEmpty)
+}
+
+@Test("Rendered page is not blank (pdftoppm, pinned renderer + rounding)")
+func renderedPageIsNotBlank() throws {
+    let directory = try makeScratchDirectory()
+    defer { try? FileManager.default.removeItem(at: directory) }
+
+    let capture = makeCapture(sequence: 1, pixelWidth: 1600, pixelHeight: 900)
+    let png = try writePNG(for: capture, red: 128, green: 128, blue: 128, in: directory)
+    let output = directory.appendingPathComponent("not-blank.pdf")
+    _ = try PDFComposer().compose(
+        session: makeSession(captures: [capture]),
+        imageURL: { _ in png },
+        title: "Not blank",
+        to: output
+    )
+    let prefix = directory.appendingPathComponent("not-blank")
+    try pdftoppm(pdf: output, prefix: prefix)
+    let rendered = directory.appendingPathComponent("not-blank-1.png")
+    let bitmap = try RGBABitmap.loadPNG(at: rendered)
+    let layout = PageLayout(capture: capture, pageIndex: 1, pageCount: 1)
+    let k: CGFloat = 110.0 / 72.0
+    let imageWin = pixelWindow(for: layout.imageRect, pageHeightPt: layout.pageRect.height, scale: k)
+    let headerWin = pixelWindow(for: layout.headerRect, pageHeightPt: layout.pageRect.height, scale: k)
+    #expect(bitmap.containsNonWhite(x0: imageWin.x0, y0: imageWin.y0, x1: imageWin.x1, y1: imageWin.y1))
+    #expect(bitmap.containsNonWhite(x0: headerWin.x0, y0: headerWin.y0, x1: headerWin.x1, y1: headerWin.y1))
+}
+
+@Test("Right-edge tick group geometry matches D-12 exactly, both orientations")
+func rightEdgeTickGroupGeometry() throws {
+    let landscape = makeCapture(sequence: 1, pixelWidth: 1600, pixelHeight: 900)
+    let portrait = makeCapture(sequence: 1, pixelWidth: 900, pixelHeight: 1600)
+    let landscapeLayout = PageLayout(capture: landscape, pageIndex: 1, pageCount: 1)
+    let portraitLayout = PageLayout(capture: portrait, pageIndex: 1, pageCount: 1)
+
+    #expect(landscapeLayout.failTickBox.maxX == 824)
+    #expect(landscapeLayout.headerRect.maxX == 824)
+    #expect(portraitLayout.failTickBox.maxX == 577)
+    #expect(portraitLayout.headerRect.maxX == 577)
+    #expect(landscapeLayout.failTickBox.width == 13)
+    #expect(landscapeLayout.failTickBox.height == 13)
+    #expect(portraitLayout.failTickBox.width == 13)
+    #expect(portraitLayout.failTickBox.height == 13)
+    #expect(landscapeLayout.passTickBox.maxX == landscapeLayout.failLabelOrigin.x - 8)
+    #expect(portraitLayout.passTickBox.maxX == portraitLayout.failLabelOrigin.x - 8)
+}
+
+@Test("Writes visual sample for review")
+func writesVisualSampleForReview() throws {
+    let verifyDir = URL(fileURLWithPath: "/Users/benjaminhippler/mmd-projects/multi-agent-runs/shotdeck-20260830/verify")
+    try FileManager.default.createDirectory(at: verifyDir, withIntermediateDirectories: true)
+    let scratch = try makeScratchDirectory()
+    defer { try? FileManager.default.removeItem(at: scratch) }
+
+    let wide = makeCapture(sequence: 1, pixelWidth: 1600, pixelHeight: 900)
+    let tall = makeCapture(sequence: 2, pixelWidth: 900, pixelHeight: 1600)
+    let retina = makeCapture(sequence: 3, pixelWidth: 2880, pixelHeight: 1620, scale: 2.0)
+    let urls: [UUID: URL] = [
+        wide.id: try writePNG(for: wide, red: 196, green: 42, blue: 42, in: scratch),
+        tall.id: try writePNG(for: tall, red: 32, green: 96, blue: 176, in: scratch),
+        retina.id: try writePNG(for: retina, red: 36, green: 148, blue: 84, in: scratch),
+    ]
+    let output = verifyDir.appendingPathComponent("wp2-sample.pdf")
+    let pageCount = try PDFComposer().compose(
+        session: makeSession(captures: [wide, tall, retina]),
+        imageURL: imageURLMap(urls),
+        title: "WP-2 visual sample",
+        to: output
+    )
+    #expect(pageCount == 3)
+    let prefix = verifyDir.appendingPathComponent("wp2-sample")
+    try pdftoppm(pdf: output, prefix: prefix)
+}