fix: archive only after AirDrop completes; PDF named by send time; Reveal last PDF

Info.plist

@@ -18,6 +18,8 @@
 	<string>0.1.0</string>
 	<key>CFBundleVersion</key>
 	<string>1</string>
+	<key>CFBundleIconFile</key>
+	<string>AppIcon</string>
 	<key>LSUIElement</key>
 	<true/>
 	<key>LSMinimumSystemVersion</key>

Sources/Shotdeck/AppModel.swift

@@ -36,6 +36,8 @@ public final class AppModel {
     public private(set) var outboxURL: URL
     /// Live watch folder; WP-4c updates this alongside `ReturnWatcher.updateWatchFolder`.
     public private(set) var watchFolderURL: URL
+    /// Absolute URL of the PDF composed this run, if any. Used by "Reveal last PDF".
+    public private(set) var lastComposedPDFURL: URL?
     /// Currently bound capture combo (the last one Carbon accepted, or the preferred load).
     private(set) var captureHotkey: HotkeyPreference
     var hotkeyDisplayString: String { captureHotkey.displayString }
@@ -105,6 +107,42 @@ public final class AppModel {
         watchFolderURL = watch
         setFolderDisplayNames(outbox: outbox.lastPathComponent, watch: watch.lastPathComponent)
     }
+    func rememberLastComposedPDF(_ url: URL) { lastComposedPDFURL = url }
+
+    /// True when a last-composed PDF path is known this run, or the newest
+    /// `Redline-*.pdf` in the outbox exists on disk.
+    var canRevealLastPDF: Bool { revealablePDFURL() != nil }
+
+    public func revealLastPDF() {
+        guard let url = revealablePDFURL() else { return }
+        NSWorkspace.shared.activateFileViewerSelecting([url])
+    }
+
+    func revealablePDFURL() -> URL? {
+        if let last = lastComposedPDFURL, FileManager.default.fileExists(atPath: last.path) {
+            return last
+        }
+        return newestOutboxRedlinePDF()
+    }
+
+    func newestOutboxRedlinePDF() -> URL? {
+        let fm = FileManager.default
+        let items = (try? fm.contentsOfDirectory(
+            at: outboxURL,
+            includingPropertiesForKeys: [.contentModificationDateKey],
+            options: [.skipsHiddenFiles]
+        )) ?? []
+        let matches = items.filter {
+            $0.lastPathComponent.hasPrefix("Redline-") && $0.pathExtension.lowercased() == "pdf"
+        }
+        return matches.max { a, b in
+            let da = (try? a.resourceValues(forKeys: [.contentModificationDateKey])
+                .contentModificationDate) ?? .distantPast
+            let db = (try? b.resourceValues(forKeys: [.contentModificationDateKey])
+                .contentModificationDate) ?? .distantPast
+            return da < db
+        }
+    }
 
     public var iconState: MenuIconState {
         if !screenRecordingGranted { return .recordingMissing }

Sources/Shotdeck/MenuBarView.swift

@@ -86,6 +86,13 @@ struct MenuBarView: View {
             }
             .disabled(model.session.isEmpty || model.isSending)
 
+            Button {
+                model.revealLastPDF()
+            } label: {
+                actionLabel("Reveal last PDF")
+            }
+            .disabled(!model.canRevealLastPDF)
+
             Button {
                 Task { await model.captureNow() }
             } label: {

Sources/Shotdeck/PickerSelfTest.swift

@@ -1,6 +1,8 @@
 import AppKit
+import CoreGraphics
 import Darwin
 import Foundation
+import ImageIO
 import ShotdeckCore
 
 /// In-process self-test for the region picker, driven by `SHOTDECK_PICKER_SELFTEST`.
@@ -113,7 +115,9 @@ enum PickerSelfTest {
         fflush(stdout)
 
         runRegionPersistPhase()
-        exit(0)
+        // Hop off this MainActor job so the SEND-TRUTH Task can run; do not
+        // exit(0) here — runSendTruthPhase exits when it finishes.
+        runSendTruthPhase()
     }
 
     /// Phase 2: writes a known region under `CaptureRegion.defaultsKey`, reloads it through
@@ -157,6 +161,142 @@ enum PickerSelfTest {
         fflush(stdout)
     }
 
+    /// Phase 3: drive SendController's share-outcome seams with no AirDrop sheet.
+    /// Fail path must leave the session open in the temp spool; success path archives
+    /// and mints a fresh empty session. Scheduled as a new MainActor job because this
+    /// function is called from inside `execute()` — a nested run-loop wait would never
+    /// let the Task start.
+    private static func runSendTruthPhase() {
+        Task { @MainActor in
+            do {
+                try await executeSendTruth()
+                print("SEND-TRUTH PASS")
+                fflush(stdout)
+                exit(0)
+            } catch {
+                print("SEND-TRUTH FAIL \(error)")
+                fflush(stdout)
+                exit(1)
+            }
+        }
+    }
+
+    private static func executeSendTruth() async throws {
+        let fm = FileManager.default
+        let root = fm.temporaryDirectory
+            .appendingPathComponent("shotdeck-send-truth-\(UUID().uuidString)", isDirectory: true)
+        defer { try? fm.removeItem(at: root) }
+
+        let paths = try AppSupportPaths(
+            root: root,
+            outbox: root.appendingPathComponent("outbox", isDirectory: true),
+            watchFolder: root.appendingPathComponent("watch", isDirectory: true)
+        )
+        let ledger = try ReturnLedger(paths: paths)
+        let model = AppModel(
+            paths: paths,
+            spool: try SpoolStore(paths: paths),
+            composer: PDFComposer(),
+            capturer: ScreenCapturer(),
+            hotkeys: HotkeyCenter(),
+            picker: RegionPickerController(),
+            ledger: ledger,
+            watcher: ReturnWatcher(paths: paths, ledger: ledger)
+        )
+        model.setFolderURLs(outbox: paths.outbox, watch: paths.watchFolder)
+
+        let png = try makeTinyPNGData()
+        _ = try await model.spool.append(
+            pngData: png,
+            pixelWidth: 64,
+            pixelHeight: 48,
+            scale: 1,
+            capturedAt: Date()
+        )
+        model.replaceSession(try await model.spool.currentSession())
+        let openID = model.session.id
+        guard !model.session.isEmpty else {
+            sendTruthFail("seeded session was empty")
+        }
+
+        let pending = try await model.composePDFForSend()
+        guard fm.fileExists(atPath: pending.fileURL.path) else {
+            sendTruthFail("PDF was not written")
+        }
+
+        model.handleDidFailToShareItems(fileName: pending.fileName)
+        let still = try await model.spool.currentSession()
+        guard still.id == openID, !still.isEmpty, still.state == .open else {
+            sendTruthFail("fail path archived or replaced the session")
+        }
+        let spoolDir = paths.sessionDirectory(openID)
+        guard fm.fileExists(atPath: spoolDir.path) else {
+            sendTruthFail("fail path: session missing from temp spool")
+        }
+        guard let status = model.statusLine, status.contains("nothing was sent") else {
+            sendTruthFail("fail path status missing 'nothing was sent': \(model.statusLine ?? "nil")")
+        }
+
+        await model.handleDidShareItems(fileName: pending.fileName, pageCount: pending.pageCount)
+        let fresh = try await model.spool.currentSession()
+        guard fresh.isEmpty, fresh.id != openID, fresh.state == .open else {
+            sendTruthFail("success path did not mint a fresh empty session")
+        }
+        let archived = try await model.spool.archivedSessions()
+        guard archived.contains(where: { $0.id == openID && $0.state == .archived }) else {
+            sendTruthFail("success path did not archive the session")
+        }
+        let archiveDir = paths.archiveDirectory(openID)
+        guard fm.fileExists(atPath: archiveDir.path) else {
+            sendTruthFail("success path: archive dir missing")
+        }
+        guard !fm.fileExists(atPath: spoolDir.path) else {
+            sendTruthFail("success path: session still in spool")
+        }
+    }
+
+    private static func makeTinyPNGData() throws -> Data {
+        let width = 64
+        let height = 48
+        let colorSpace = CGColorSpaceCreateDeviceRGB()
+        guard let context = CGContext(
+            data: nil,
+            width: width,
+            height: height,
+            bitsPerComponent: 8,
+            bytesPerRow: width * 4,
+            space: colorSpace,
+            bitmapInfo: CGImageAlphaInfo.premultipliedLast.rawValue
+        ) else {
+            sendTruthFail("could not create PNG context")
+        }
+        context.setFillColor(red: 0.2, green: 0.4, blue: 0.8, alpha: 1)
+        context.fill(CGRect(x: 0, y: 0, width: width, height: height))
+        guard let image = context.makeImage() else {
+            sendTruthFail("could not make CGImage")
+        }
+        let buffer = NSMutableData()
+        guard let destination = CGImageDestinationCreateWithData(
+            buffer,
+            "public.png" as CFString,
+            1,
+            nil
+        ) else {
+            sendTruthFail("could not create PNG destination")
+        }
+        CGImageDestinationAddImage(destination, image, nil)
+        guard CGImageDestinationFinalize(destination) else {
+            sendTruthFail("could not finalize PNG")
+        }
+        return buffer as Data
+    }
+
+    private static func sendTruthFail(_ reason: String) -> Never {
+        print("SEND-TRUTH FAIL \(reason)")
+        fflush(stdout)
+        exit(1)
+    }
+
     private static func interpolate(_ step: Int) -> NSPoint {
         let t = CGFloat(step) / CGFloat(dragSteps)
         return NSPoint(

Sources/Shotdeck/SendController.swift

@@ -3,12 +3,59 @@ import Darwin
 import Foundation
 import ShotdeckCore
 
+/// Result of composing a send PDF. Kept so the self-test can drive the share
+/// outcome without presenting a real AirDrop sheet.
+struct ComposedSend: Sendable {
+    let fileName: String
+    let fileURL: URL
+    let pageCount: Int
+}
+
 extension AppModel: SendCapable {
     public func send(anchor: NSView?) async {
         guard !session.isEmpty, !isSending else { return }
         setSending(true)
-        defer { setSending(false) }
 
+        let pending: ComposedSend
+        do {
+            pending = try await composePDFForSend()
+        } catch {
+            // Never unlink the published PDF, and never unlink the temp file either:
+            // a rename failure would leave the complete document at the temp name.
+            setStatus((error as? ShotdeckError)?.errorDescription ?? "The PDF could not be built.")
+            setSending(false)
+            return
+        }
+
+        guard let anchor else {
+            handleDidFailToShareItems(fileName: pending.fileName)
+            setSending(false)
+            return
+        }
+
+        do {
+            try Sharing.airDrop(fileURL: pending.fileURL, from: anchor) { [weak self] success in
+                guard let self else { return }
+                if success {
+                    await self.handleDidShareItems(
+                        fileName: pending.fileName,
+                        pageCount: pending.pageCount
+                    )
+                } else {
+                    self.handleDidFailToShareItems(fileName: pending.fileName)
+                }
+                self.setSending(false)
+            }
+        } catch {
+            // canPerform false, no service, or no visible window: same as cancel.
+            handleDidFailToShareItems(fileName: pending.fileName)
+            setSending(false)
+        }
+    }
+
+    /// Writes the PDF to the outbox and records its path. Does not archive the session
+    /// and does not present AirDrop — that happens only after the share completes.
+    func composePDFForSend() async throws -> ComposedSend {
         let workingSession = session
         let composer = self.composer
         // Live outbox (FolderSettings), not `paths.outbox` — Settings changes take effect.
@@ -20,52 +67,54 @@ extension AppModel: SendCapable {
         let tempURL = outboxDir.appendingPathComponent(".shotdeck-\(UUID().uuidString).pdf")
         let title = "Redline – \(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
+        // 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)))"
                 )
-                // 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 AtomicFile.fsyncDirectory(at: outboxDir)
+        }.value
+
+        guard FileManager.default.fileExists(atPath: finalURL.path) else {
+            throw ShotdeckError.pdfCompositionFailed(reason: "the PDF was not written to disk")
+        }
+        rememberLastComposedPDF(finalURL)
+        return ComposedSend(
+            fileName: fileName,
+            fileURL: finalURL,
+            pageCount: workingSession.captures.count
+        )
+    }
+
+    /// `NSSharingServiceDelegate.sharingService(_:didShareItems:)` seam.
+    func handleDidShareItems(fileName: String, pageCount: Int) async {
+        guard !session.isEmpty else { return }
+        do {
             _ = 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)."
-                )
-            }
+            let pageWord = pageCount == 1 ? "page" : "pages"
+            setStatus("Sent — \(pageCount) \(pageWord).")
         } 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.")
+            setStatus((error as? ShotdeckError)?.errorDescription ?? "Could not archive the session.")
         }
     }
+
+    /// `NSSharingServiceDelegate.sharingService(_:didFailToShareItems:error:)` seam,
+    /// also used when `canPerform` is false or the user cancels. Does not archive.
+    func handleDidFailToShareItems(fileName: String) {
+        setStatus(
+            "AirDrop didn't complete — nothing was sent. Your captures are still here; the PDF is on your \(outboxDisplayName) as \(fileName)."
+        )
+    }
 }

Sources/Shotdeck/Sharing.swift

@@ -7,7 +7,14 @@ enum Sharing {
     /// 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 {
+    ///
+    /// `onFinished` is invoked on the main actor when the sheet completes: `true` for
+    /// `didShareItems`, `false` for `didFailToShareItems` (including user cancel).
+    static func airDrop(
+        fileURL: URL,
+        from view: NSView,
+        onFinished: @escaping @MainActor @Sendable (Bool) async -> Void
+    ) throws {
         guard let service = NSSharingService(named: .sendViaAirDrop),
               service.canPerform(withItems: [fileURL]) else {
             throw ShotdeckError.airDropUnavailable
@@ -21,7 +28,12 @@ enum Sharing {
         window.makeKeyAndOrderFront(nil)
 
         service.subject = fileURL.lastPathComponent
-        let session = AirDropSession(service: service, window: window, view: view)
+        let session = AirDropSession(
+            service: service,
+            window: window,
+            view: view,
+            onFinished: onFinished
+        )
         AirDropSession.keepAlive(session)
         service.delegate = session
         service.perform(withItems: [fileURL])
@@ -29,7 +41,9 @@ enum Sharing {
 }
 
 /// 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.
+/// on-screen window as the sheet parent. `NSSharingService.delegate` is weak, so
+/// `live` is the strong reference that keeps this object alive until the sheet
+/// reports success or failure (including cancel).
 @MainActor
 private final class AirDropSession: NSObject, NSSharingServiceDelegate {
     static var live: [AirDropSession] = []
@@ -37,11 +51,19 @@ private final class AirDropSession: NSObject, NSSharingServiceDelegate {
     let service: NSSharingService
     let window: NSWindow
     let view: NSView
+    let onFinished: @MainActor @Sendable (Bool) async -> Void
+    private var reported = false
 
-    init(service: NSSharingService, window: NSWindow, view: NSView) {
+    init(
+        service: NSSharingService,
+        window: NSWindow,
+        view: NSView,
+        onFinished: @escaping @MainActor @Sendable (Bool) async -> Void
+    ) {
         self.service = service
         self.window = window
         self.view = view
+        self.onFinished = onFinished
     }
 
     static func keepAlive(_ session: AirDropSession) {
@@ -52,6 +74,15 @@ private final class AirDropSession: NSObject, NSSharingServiceDelegate {
         Self.live.removeAll { $0 === self }
     }
 
+    private func report(_ success: Bool) {
+        guard !reported else { return }
+        reported = true
+        Task { @MainActor in
+            await self.onFinished(success)
+            self.drop()
+        }
+    }
+
     func sharingService(
         _ sharingService: NSSharingService,
         sourceWindowForShareItems items: [Any],
@@ -70,7 +101,7 @@ private final class AirDropSession: NSObject, NSSharingServiceDelegate {
     }
 
     func sharingService(_ sharingService: NSSharingService, didShareItems items: [Any]) {
-        drop()
+        report(true)
     }
 
     func sharingService(
@@ -78,6 +109,6 @@ private final class AirDropSession: NSObject, NSSharingServiceDelegate {
         didFailToShareItems items: [Any],
         error: any Error
     ) {
-        drop()
+        report(false)
     }
 }

Sources/ShotdeckCore/PDF/PDFComposer.swift

@@ -70,8 +70,8 @@ public struct PDFComposer: Sendable {
         }
     }
 
-    public static func fileName(for session: CaptureSession) -> String {
-        "Redline-\(DubaiTime.fileStamp(session.createdAt)).pdf"
+    public static func fileName(for _: CaptureSession) -> String {
+        "Redline-\(DubaiTime.fileStamp(Date())).pdf"
     }
 
     private static func writePDF(

Tests/ShotdeckCoreTests/PDFComposerTests.swift

@@ -203,6 +203,17 @@ private func pixelWindow(
     return (pixelX0, pixelY0, pixelX1, pixelY1)
 }
 
+@Test("fileName uses compose time, not session.createdAt, and matches Redline-yyyyMMdd-HHmmss.pdf")
+func fileNameUsesComposeTimeNotSessionCreatedAt() {
+    let old = Date(timeIntervalSince1970: 1_600_000_000) // 2020-09-13
+    let session = makeSession(captures: [], createdAt: old)
+    let name = PDFComposer.fileName(for: session)
+    #expect(name.wholeMatch(of: /^Redline-\d{8}-\d{6}\.pdf$/) != nil)
+    #expect(!name.contains(DubaiTime.fileStamp(old)))
+    let today = String(DubaiTime.fileStamp(Date()).prefix(8))
+    #expect(name.contains(today))
+}
+
 @Test("Three-page basic compose")
 func threePageBasicCompose() throws {
     let directory = try makeScratchDirectory()

scripts/build-app.sh

@@ -43,6 +43,7 @@ mkdir -p "${APP_BUNDLE}/Contents/Resources"
 cp "${BIN_PATH}" "${APP_BUNDLE}/Contents/MacOS/Shotdeck"
 chmod +x "${APP_BUNDLE}/Contents/MacOS/Shotdeck"
 cp "${ROOT}/Info.plist" "${APP_BUNDLE}/Contents/Info.plist"
+cp "${ROOT}/Resources/AppIcon.icns" "${APP_BUNDLE}/Contents/Resources/AppIcon.icns"
 
 if [[ "${SKIP_SIGN}" -eq 1 ]]; then
     echo

scripts/make-icon.swift

@@ -0,0 +1,324 @@
+#!/usr/bin/env swift
+import Foundation
+import CoreGraphics
+import ImageIO
+
+// Programmatic Redline app icon.
+// Draws a 1024×1024 master, writes AppIcon.iconset (16…1024 incl. @2x),
+// and compiles Resources/AppIcon.icns via iconutil.
+//
+// Usage:
+//   swift scripts/make-icon.swift
+//   swift scripts/make-icon.swift --preview /path/to/icon-512.png
+
+private let masterSize = 1024
+
+private enum Palette {
+    static let charcoalTop = CGColor(srgbRed: 44.0 / 255.0, green: 44.0 / 255.0, blue: 46.0 / 255.0, alpha: 1)
+    static let charcoalBottom = CGColor(srgbRed: 28.0 / 255.0, green: 28.0 / 255.0, blue: 30.0 / 255.0, alpha: 1) // #1C1C1E
+    static let white = CGColor(srgbRed: 1, green: 1, blue: 1, alpha: 1)
+    static let redline = CGColor(srgbRed: 229.0 / 255.0, green: 72.0 / 255.0, blue: 63.0 / 255.0, alpha: 1) // #E5483F
+}
+
+private struct IconsetEntry {
+    let filename: String
+    let pixels: Int
+}
+
+private let iconsetEntries: [IconsetEntry] = [
+    IconsetEntry(filename: "icon_16x16.png", pixels: 16),
+    IconsetEntry(filename: "icon_16x16@2x.png", pixels: 32),
+    IconsetEntry(filename: "icon_32x32.png", pixels: 32),
+    IconsetEntry(filename: "icon_32x32@2x.png", pixels: 64),
+    IconsetEntry(filename: "icon_128x128.png", pixels: 128),
+    IconsetEntry(filename: "icon_128x128@2x.png", pixels: 256),
+    IconsetEntry(filename: "icon_256x256.png", pixels: 256),
+    IconsetEntry(filename: "icon_256x256@2x.png", pixels: 512),
+    IconsetEntry(filename: "icon_512x512.png", pixels: 512),
+    IconsetEntry(filename: "icon_512x512@2x.png", pixels: 1024),
+]
+
+// MARK: - Geometry
+
+/// Apple-style continuous-corner rounded square (squircle-like).
+/// Superellipse |x/a|^n + |y/b|^n = 1 with n≈5, inset 1px so antialiased
+/// edge pixels are not clipped by the bitmap.
+private func continuousRoundedSquare(size: CGFloat, exponent n: CGFloat = 5.0, segments: Int = 256) -> CGPath {
+    let inset: CGFloat = 1
+    let a = (size - inset * 2) / 2
+    let cx = size / 2
+    let cy = size / 2
+    let twoOverN = 2 / n
+    let path = CGMutablePath()
+    for i in 0...segments {
+        let theta = CGFloat(i) / CGFloat(segments) * 2 * .pi
+        let ct = cos(theta)
+        let st = sin(theta)
+        let x = cx + (ct < 0 ? -1 : 1) * pow(abs(ct), twoOverN) * a
+        let y = cy + (st < 0 ? -1 : 1) * pow(abs(st), twoOverN) * a
+        if i == 0 {
+            path.move(to: CGPoint(x: x, y: y))
+        } else {
+            path.addLine(to: CGPoint(x: x, y: y))
+        }
+    }
+    path.closeSubpath()
+    return path
+}
+
+// MARK: - Drawing
+
+private func drawMasterIcon(size: Int) -> CGImage {
+    let s = CGFloat(size)
+    let colorSpace = CGColorSpace(name: CGColorSpace.sRGB)!
+    let bitmapInfo = CGBitmapInfo.byteOrder32Big.rawValue | CGImageAlphaInfo.premultipliedLast.rawValue
+    guard let ctx = CGContext(
+        data: nil,
+        width: size,
+        height: size,
+        bitsPerComponent: 8,
+        bytesPerRow: 0,
+        space: colorSpace,
+        bitmapInfo: bitmapInfo
+    ) else {
+        fputs("error: failed to create \(size)×\(size) bitmap context\n", stderr)
+        exit(1)
+    }
+
+    ctx.setShouldAntialias(true)
+    ctx.setAllowsAntialiasing(true)
+    ctx.interpolationQuality = .high
+
+    // Flip to top-left origin so "top-to-bottom gradient" is literal.
+    ctx.translateBy(x: 0, y: s)
+    ctx.scaleBy(x: 1, y: -1)
+
+    ctx.clear(CGRect(x: 0, y: 0, width: s, height: s))
+
+    let squircle = continuousRoundedSquare(size: s)
+
+    ctx.saveGState()
+    ctx.addPath(squircle)
+    ctx.clip()
+
+    let gradient = CGGradient(
+        colorsSpace: colorSpace,
+        colors: [Palette.charcoalTop, Palette.charcoalBottom] as CFArray,
+        locations: [0, 1]
+    )!
+    ctx.drawLinearGradient(
+        gradient,
+        start: CGPoint(x: s / 2, y: 0),
+        end: CGPoint(x: s / 2, y: s),
+        options: [.drawsBeforeStartLocation, .drawsAfterEndLocation]
+    )
+    ctx.restoreGState()
+
+    // Viewfinder corner brackets: thick L-strokes, rounded caps/joins, inset ~18%.
+    let inset = s * 0.18
+    let bracketWidth = s * 0.095
+    let arm = s * 0.155
+    let centerline = inset + bracketWidth / 2
+
+    ctx.saveGState()
+    ctx.addPath(squircle)
+    ctx.clip()
+    ctx.setStrokeColor(Palette.white)
+    ctx.setLineWidth(bracketWidth)
+    ctx.setLineCap(.round)
+    ctx.setLineJoin(.round)
+
+    func strokeBracket(cornerX: CGFloat, cornerY: CGFloat, dirX: CGFloat, dirY: CGFloat) {
+        let path = CGMutablePath()
+        path.move(to: CGPoint(x: cornerX + dirX * arm, y: cornerY))
+        path.addLine(to: CGPoint(x: cornerX, y: cornerY))
+        path.addLine(to: CGPoint(x: cornerX, y: cornerY + dirY * arm))
+        ctx.addPath(path)
+        ctx.strokePath()
+    }
+
+    // Top-left, top-right, bottom-left, bottom-right.
+    strokeBracket(cornerX: centerline, cornerY: centerline, dirX: 1, dirY: 1)
+    strokeBracket(cornerX: s - centerline, cornerY: centerline, dirX: -1, dirY: 1)
+    strokeBracket(cornerX: centerline, cornerY: s - centerline, dirX: 1, dirY: -1)
+    strokeBracket(cornerX: s - centerline, cornerY: s - centerline, dirX: -1, dirY: -1)
+
+    // Bold redline slash over the frame, lower-left bracket area → upper-right.
+    let slashWidth = s * 0.078
+    ctx.setStrokeColor(Palette.redline)
+    ctx.setLineWidth(slashWidth)
+    ctx.setLineCap(.round)
+    ctx.setLineJoin(.round)
+    let slashInset = centerline + arm * 0.12
+    let slash = CGMutablePath()
+    slash.move(to: CGPoint(x: slashInset, y: s - slashInset))
+    slash.addLine(to: CGPoint(x: s - slashInset, y: slashInset))
+    ctx.addPath(slash)
+    ctx.strokePath()
+    ctx.restoreGState()
+
+    guard let image = ctx.makeImage() else {
+        fputs("error: failed to materialize master CGImage\n", stderr)
+        exit(1)
+    }
+    return image
+}
+
+private func scaledImage(_ image: CGImage, pixels: Int) -> CGImage {
+    if image.width == pixels && image.height == pixels {
+        return image
+    }
+    let colorSpace = CGColorSpace(name: CGColorSpace.sRGB)!
+    let bitmapInfo = CGBitmapInfo.byteOrder32Big.rawValue | CGImageAlphaInfo.premultipliedLast.rawValue
+    guard let ctx = CGContext(
+        data: nil,
+        width: pixels,
+        height: pixels,
+        bitsPerComponent: 8,
+        bytesPerRow: 0,
+        space: colorSpace,
+        bitmapInfo: bitmapInfo
+    ) else {
+        fputs("error: failed to create \(pixels)×\(pixels) scale context\n", stderr)
+        exit(1)
+    }
+    ctx.interpolationQuality = .high
+    ctx.setShouldAntialias(true)
+    ctx.draw(image, in: CGRect(x: 0, y: 0, width: pixels, height: pixels))
+    guard let out = ctx.makeImage() else {
+        fputs("error: failed to scale image to \(pixels)px\n", stderr)
+        exit(1)
+    }
+    return out
+}
+
+private func writePNG(_ image: CGImage, to url: URL) {
+    let dir = url.deletingLastPathComponent()
+    try? FileManager.default.createDirectory(at: dir, withIntermediateDirectories: true)
+    if FileManager.default.fileExists(atPath: url.path) {
+        try? FileManager.default.removeItem(at: url)
+    }
+    guard let dest = CGImageDestinationCreateWithURL(url as CFURL, "public.png" as CFString, 1, nil) else {
+        fputs("error: cannot create PNG destination at \(url.path)\n", stderr)
+        exit(1)
+    }
+    CGImageDestinationAddImage(dest, image, nil)
+    if !CGImageDestinationFinalize(dest) {
+        fputs("error: failed to write PNG \(url.path)\n", stderr)
+        exit(1)
+    }
+}
+
+// MARK: - Paths / CLI
+
+private func repoRoot() -> URL {
+    let cwd = URL(fileURLWithPath: FileManager.default.currentDirectoryPath, isDirectory: true)
+    let arg0 = URL(fileURLWithPath: CommandLine.arguments[0])
+    let scriptURL: URL
+    if arg0.path.hasPrefix("/") {
+        scriptURL = arg0.standardizedFileURL
+    } else {
+        scriptURL = cwd.appendingPathComponent(arg0.path).standardizedFileURL
+    }
+    let fromScript = scriptURL.deletingLastPathComponent().deletingLastPathComponent()
+    if FileManager.default.fileExists(atPath: fromScript.appendingPathComponent("Package.swift").path) {
+        return fromScript
+    }
+    if FileManager.default.fileExists(atPath: cwd.appendingPathComponent("Package.swift").path) {
+        return cwd
+    }
+    fputs("error: could not find repo root (Package.swift)\n", stderr)
+    exit(1)
+}
+
+private func parsePreviewPath() -> String? {
+    let args = CommandLine.arguments
+    var i = 1
+    var preview: String?
+    while i < args.count {
+        let arg = args[i]
+        if arg == "--preview" {
+            i += 1
+            guard i < args.count else {
+                fputs("error: --preview requires a path\n", stderr)
+                exit(1)
+            }
+            preview = args[i]
+        } else if arg.hasPrefix("--preview=") {
+            preview = String(arg.dropFirst("--preview=".count))
+        } else if arg == "--help" || arg == "-h" {
+            fputs("Usage: swift scripts/make-icon.swift [--preview PATH]\n", stderr)
+            exit(0)
+        } else {
+            fputs("error: unknown argument \(arg)\n", stderr)
+            fputs("Usage: swift scripts/make-icon.swift [--preview PATH]\n", stderr)
+            exit(1)
+        }
+        i += 1
+    }
+    return preview
+}
+
+private func runIconutil(iconset: URL, icns: URL) {
+    let proc = Process()
+    proc.executableURL = URL(fileURLWithPath: "/usr/bin/iconutil")
+    proc.arguments = ["-c", "icns", iconset.path, "-o", icns.path]
+    proc.standardOutput = FileHandle.standardOutput
+    proc.standardError = FileHandle.standardError
+    do {
+        try proc.run()
+        proc.waitUntilExit()
+    } catch {
+        fputs("error: failed to launch iconutil: \(error)\n", stderr)
+        exit(1)
+    }
+    if proc.terminationStatus != 0 {
+        fputs("error: iconutil exited \(proc.terminationStatus)\n", stderr)
+        exit(1)
+    }
+}
+
+// MARK: - Main
+
+let root = repoRoot()
+let resources = root.appendingPathComponent("Resources", isDirectory: true)
+let icnsURL = resources.appendingPathComponent("AppIcon.icns")
+let previewPath = parsePreviewPath()
+let fm = FileManager.default
+
+print("==> Drawing \(masterSize)×\(masterSize) master")
+let master = drawMasterIcon(size: masterSize)
+
+let iconset = fm.temporaryDirectory.appendingPathComponent("Redline-AppIcon-\(UUID().uuidString).iconset", isDirectory: true)
+
+do {
+    try fm.createDirectory(at: iconset, withIntermediateDirectories: true)
+    try fm.createDirectory(at: resources, withIntermediateDirectories: true)
+
+    print("==> Writing AppIcon.iconset")
+    for entry in iconsetEntries {
+        let img = scaledImage(master, pixels: entry.pixels)
+        writePNG(img, to: iconset.appendingPathComponent(entry.filename))
+    }
+
+    if fm.fileExists(atPath: icnsURL.path) {
+        try fm.removeItem(at: icnsURL)
+    }
+
+    print("==> Compiling \(icnsURL.path)")
+    runIconutil(iconset: iconset, icns: icnsURL)
+
+    try? fm.removeItem(at: iconset)
+} catch {
+    try? fm.removeItem(at: iconset)
+    fputs("error: \(error)\n", stderr)
+    exit(1)
+}
+
+if let previewPath {
+    let previewURL = URL(fileURLWithPath: previewPath)
+    print("==> Writing 512px preview \(previewURL.path)")
+    writePNG(scaledImage(master, pixels: 512), to: previewURL)
+}
+
+print("App icon: \(icnsURL.path)")