Sync settings sidebar and open notifications at turn start

Packages/CmuxSettingsUI/Sources/CmuxSettingsUI/Navigation/SettingsSectionFramePreferenceKey.swift

@@ -0,0 +1,18 @@
+import CoreGraphics
+import SwiftUI
+
+struct SettingsSectionFramePreferenceKey: PreferenceKey {
+    static let defaultValue: [SettingsSectionID: CGRect] = [:]
+
+    /// Merges section frames reported by every visibility marker.
+    ///
+    /// - Parameters:
+    ///   - value: Current aggregate section frame map.
+    ///   - nextValue: Next lazily produced section frame map from SwiftUI.
+    static func reduce(
+        value: inout [SettingsSectionID: CGRect],
+        nextValue: () -> [SettingsSectionID: CGRect]
+    ) {
+        value.merge(nextValue()) { _, newValue in newValue }
+    }
+}

Packages/CmuxSettingsUI/Sources/CmuxSettingsUI/Navigation/SettingsSectionVisibilityCoordinateSpace.swift

@@ -0,0 +1,5 @@
+struct SettingsSectionVisibilityCoordinateSpace {
+    static let name = "SettingsSectionVisibilityCoordinateSpace"
+
+    private init() {}
+}

Packages/CmuxSettingsUI/Sources/CmuxSettingsUI/Navigation/SettingsSectionVisibilityMarker.swift

@@ -0,0 +1,24 @@
+import SwiftUI
+
+struct SettingsSectionVisibilityMarker: View {
+    let section: SettingsSectionID
+
+    var body: some View {
+        GeometryReader { proxy in
+            Color.clear.preference(
+                key: SettingsSectionFramePreferenceKey.self,
+                value: [section: proxy.frame(in: .named(SettingsSectionVisibilityCoordinateSpace.name))]
+            )
+        }
+    }
+}
+
+extension View {
+    /// Reports this view's frame as the scroll-position marker for a settings section.
+    ///
+    /// - Parameter section: Section represented by the view.
+    /// - Returns: A view that publishes its frame through `SettingsSectionFramePreferenceKey`.
+    func settingsSectionVisibility(_ section: SettingsSectionID) -> some View {
+        background(SettingsSectionVisibilityMarker(section: section))
+    }
+}

Packages/CmuxSettingsUI/Sources/CmuxSettingsUI/Navigation/SettingsSidebarEntryRow.swift

@@ -9,9 +9,11 @@ import SwiftUI
 /// than wrap and inflate row height.
 @MainActor
 struct SettingsSidebarEntryRow: View {
+    let id: String
     let title: String
     let symbolName: String
     let subtitle: String?
+    let isSelected: Bool
 
     var body: some View {
         HStack(spacing: 10) {
@@ -32,5 +34,7 @@ struct SettingsSidebarEntryRow: View {
             }
         }
         .frame(maxWidth: .infinity, alignment: .leading)
+        .accessibilityIdentifier("SettingsSidebarEntry.\(id)")
+        .accessibilityAddTraits(isSelected ? .isSelected : [])
     }
 }

Packages/CmuxSettingsUI/Sources/CmuxSettingsUI/Navigation/SettingsVisibleSectionResolver.swift

@@ -0,0 +1,79 @@
+import CoreGraphics
+
+struct SettingsVisibleSectionResolver: Sendable {
+    struct Configuration: Sendable {
+        static let defaultActivationY: CGFloat = 0
+
+        let activationY: CGFloat
+
+        /// Creates a resolver configuration.
+        ///
+        /// - Parameter activationY: Vertical viewport coordinate that decides when
+        ///   a section becomes active. A section is active after its top edge
+        ///   crosses this coordinate.
+        init(activationY: CGFloat = Self.defaultActivationY) {
+            self.activationY = activationY
+        }
+    }
+
+    /// Resolves the section that should be selected for the current scroll position.
+    ///
+    /// - Parameters:
+    ///   - frames: Current section frames in the settings detail scroll coordinate space.
+    ///   - orderedSections: Sections in visual scroll order.
+    ///   - configuration: Resolver options, including the activation line.
+    /// - Returns: The active section, or `nil` when no tracked frames are available.
+    static func visibleSection(
+        in frames: [SettingsSectionID: CGRect],
+        orderedSections: [SettingsSectionID] = SettingsSectionID.allCases,
+        configuration: Configuration = Configuration()
+    ) -> SettingsSectionID? {
+        let orderedFrames = orderedSections.enumerated().compactMap { index, section -> SectionFrame? in
+            guard let frame = frames[section] else { return nil }
+            return SectionFrame(index: index, section: section, frame: frame)
+        }
+
+        guard !orderedFrames.isEmpty else { return nil }
+
+        let containingFrames = orderedFrames.filter {
+            $0.frame.minY <= configuration.activationY && $0.frame.maxY >= configuration.activationY
+        }
+        if let active = nearestFrameToActivationLine(in: containingFrames) {
+            return active.section
+        }
+
+        let crossedFrames = orderedFrames.filter { $0.frame.minY <= configuration.activationY }
+        if let active = nearestFrameToActivationLine(in: crossedFrames) {
+            return active.section
+        }
+
+        return orderedFrames.min(by: { lhs, rhs in
+            if lhs.frame.minY == rhs.frame.minY {
+                return lhs.index < rhs.index
+            }
+            return lhs.frame.minY < rhs.frame.minY
+        })?.section
+    }
+
+    /// Selects the frame whose top edge is closest to the activation line.
+    ///
+    /// - Parameter frames: Section frames already filtered to eligible candidates.
+    /// - Returns: The nearest eligible frame, or `nil` when no candidates exist.
+    private static func nearestFrameToActivationLine(in frames: [SectionFrame]) -> SectionFrame? {
+        if let active = frames.max(by: { lhs, rhs in
+            if lhs.frame.minY == rhs.frame.minY {
+                return lhs.index < rhs.index
+            }
+            return lhs.frame.minY < rhs.frame.minY
+        }) {
+            return active
+        }
+        return nil
+    }
+
+    private struct SectionFrame {
+        let index: Int
+        let section: SettingsSectionID
+        let frame: CGRect
+    }
+}

Packages/CmuxSettingsUI/Sources/CmuxSettingsUI/Scene/SettingsWindowScene.swift

@@ -70,6 +70,13 @@ public struct SettingsWindowRoot: View {
     // and re-checked inside the scheduled `Task { @MainActor in ... }`,
     // so only the most recent request actually scrolls.
     @State private var settingsNavigationGeneration: Int = 0
+    // Prevents the reverse "visible section -> sidebar selection" sync from
+    // racing the restored or clicked navigation target while `scrollTo` is
+    // still settling. It starts true so first-layout frame reports cannot
+    // overwrite the SceneStorage-restored section before `onAppear` scrolls
+    // there.
+    @State private var visibleSectionSyncSuppressed: Bool = true
+    @State private var latestSectionFrames: [SettingsSectionID: CGRect] = [:]
     // Drives the "flash the navigated-to row" affordance the legacy
     // settings window had. When the user clicks a search hit, the target
     // row pulses an accent border for a few seconds so the eye can find
@@ -146,6 +153,7 @@ public struct SettingsWindowRoot: View {
             // selected.
             guard newValue.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty else { return }
             selectedSidebarEntryID = sectionEntryID(for: selectedSection)
+            syncSidebarSelectionToVisibleSection(latestSectionFrames)
         }
     }
 
@@ -187,9 +195,11 @@ public struct SettingsWindowRoot: View {
             } else {
                 ForEach(matches) { entry in
                     SettingsSidebarEntryRow(
+                        id: entry.id,
                         title: entry.title,
                         symbolName: entry.symbolName,
-                        subtitle: subtitle(for: entry)
+                        subtitle: subtitle(for: entry),
+                        isSelected: selectedSidebarEntryID == entry.id
                     )
                     .tag(entry.id)
                 }
@@ -341,7 +351,13 @@ public struct SettingsWindowRoot: View {
                     .padding(.top, 20)
                     .padding(.bottom, 20)
                 }
+                .coordinateSpace(name: SettingsSectionVisibilityCoordinateSpace.name)
+                .accessibilityIdentifier("SettingsDetailScrollView")
                 .toggleStyle(.switch)
+                .onPreferenceChange(SettingsSectionFramePreferenceKey.self) { frames in
+                    latestSectionFrames = frames
+                    syncSidebarSelectionToVisibleSection(frames)
+                }
                 .onAppear {
                     // Legacy SettingsView.onAppear scrolls to the restored
                     // section so reopening the Settings window lands on
@@ -392,6 +408,7 @@ public struct SettingsWindowRoot: View {
         let sectionID = self.anchorID(for: target)
         settingsNavigationGeneration += 1
         let navigationGeneration = settingsNavigationGeneration
+        visibleSectionSyncSuppressed = true
         // Arm (or clear) the highlight before the scroll so the pulse is
         // already live when the target lands in view. A section hit
         // (anchorID == sectionID) highlights the section header; a row
@@ -422,6 +439,30 @@ public struct SettingsWindowRoot: View {
         Task { @MainActor in
             guard navigationGeneration == settingsNavigationGeneration else { return }
             proxy.scrollTo(anchorID, anchor: anchor)
+            await Task.yield()
+            guard navigationGeneration == settingsNavigationGeneration else { return }
+            visibleSectionSyncSuppressed = false
+        }
+    }
+
+    /// Syncs the sidebar's selected row to the currently visible detail section.
+    ///
+    /// - Parameter frames: Section frames reported in the settings detail scroll
+    ///   coordinate space.
+    private func syncSidebarSelectionToVisibleSection(_ frames: [SettingsSectionID: CGRect]) {
+        guard !visibleSectionSyncSuppressed else { return }
+        // Search results can select a specific setting row, not just a section.
+        // Keep that deep selection stable until the search query is cleared.
+        guard !isSearching else { return }
+        guard let visibleSection = SettingsVisibleSectionResolver.visibleSection(in: frames) else { return }
+
+        if selectedSectionRaw != visibleSection.rawValue {
+            selectedSectionRaw = visibleSection.rawValue
+        }
+
+        let sidebarEntryID = sectionEntryID(for: visibleSection)
+        if selectedSidebarEntryID != sidebarEntryID {
+            selectedSidebarEntryID = sidebarEntryID
         }
     }
 
@@ -436,13 +477,15 @@ public struct SettingsWindowRoot: View {
             catalog: catalog,
             accountFlow: accountFlow
         )
+        .settingsSectionVisibility(.account)
         .id(anchorID(for: .account))
 
         AppSection(
             defaultsStore: defaultsStore,
             catalog: catalog,
             hostActions: hostActions
         )
+        .settingsSectionVisibility(.app)
         .id(anchorID(for: .app))
 
         TerminalSection(
@@ -451,18 +494,23 @@ public struct SettingsWindowRoot: View {
             catalog: catalog,
             hostActions: hostActions
         )
+        .settingsSectionVisibility(.terminal)
         .id(anchorID(for: .terminal))
 
         TextBoxSection(defaultsStore: defaultsStore, catalog: catalog)
+            .settingsSectionVisibility(.textBox)
             .id(anchorID(for: .textBox))
 
         MobileSection(defaultsStore: defaultsStore, catalog: catalog, hostActions: hostActions)
+            .settingsSectionVisibility(.mobile)
             .id(anchorID(for: .mobile))
 
         SidebarSection(defaultsStore: defaultsStore, catalog: catalog, hostActions: hostActions)
+            .settingsSectionVisibility(.sidebarAppearance)
             .id(anchorID(for: .sidebarAppearance))
 
         BetaFeaturesSection(defaultsStore: defaultsStore, catalog: catalog)
+            .settingsSectionVisibility(.betaFeatures)
             .id(anchorID(for: .betaFeatures))
 
         AutomationSection(
@@ -472,6 +520,7 @@ public struct SettingsWindowRoot: View {
             catalog: catalog,
             errorLog: runtime.errorLog
         )
+        .settingsSectionVisibility(.automation)
         .id(anchorID(for: .automation))
 
         BrowserSection(
@@ -480,6 +529,7 @@ public struct SettingsWindowRoot: View {
             hostActions: hostActions,
             importAnchorID: anchorID(for: .browserImport)
         )
+        .settingsSectionVisibility(.browser)
         .id(anchorID(for: .browser))
 
         GlobalHotkeySection(
@@ -488,6 +538,7 @@ public struct SettingsWindowRoot: View {
             catalog: catalog,
             errorLog: runtime.errorLog
         )
+        .settingsSectionVisibility(.globalHotkey)
         .id(anchorID(for: .globalHotkey))
 
         KeyboardShortcutsSection(
@@ -496,6 +547,7 @@ public struct SettingsWindowRoot: View {
             errorLog: runtime.errorLog,
             hostActions: hostActions
         )
+        .settingsSectionVisibility(.keyboardShortcuts)
         .id(anchorID(for: .keyboardShortcuts))
 
         WorkspaceColorsSection(
@@ -504,16 +556,19 @@ public struct SettingsWindowRoot: View {
             catalog: catalog,
             errorLog: runtime.errorLog
         )
+        .settingsSectionVisibility(.workspaceColors)
         .id(anchorID(for: .workspaceColors))
 
         SettingsJSONSection(jsonStore: jsonStore, hostActions: hostActions)
+            .settingsSectionVisibility(.settingsJSON)
             .id(anchorID(for: .settingsJSON))
 
         ResetSection(
             defaultsStore: defaultsStore,
             jsonStore: jsonStore,
             catalog: catalog
         )
+        .settingsSectionVisibility(.reset)
         .id(anchorID(for: .reset))
     }
 

Packages/CmuxSettingsUI/Sources/CmuxSettingsUI/Sections/BrowserSection.swift

@@ -268,6 +268,7 @@ public struct BrowserSection: View {
                 importHintModel: importHint,
                 onImport: { hostActions.openBrowserImportFlow() }
             )
+            .settingsSectionVisibility(.browserImport)
             .id(importAnchorID ?? "section:browserImport.inline")
             .settingsSearchHighlight([importAnchorID, "setting:browserImport:import-data"].compactMap { $0 })
             SettingsCardDivider()