Merge nucleic/bold-pebble-seal into dev

NucleicRemote/NucleicRemote/Models/RemoteStore.swift

@@ -195,6 +195,7 @@ final class RemoteStore: ObservableObject {
         guard !fresh.isEmpty else { return }
         castLedger = ledger
         activityFeed = ActivityFeedItem.merged(activityFeed, adding: fresh)
+        updateComposerTyping(fresh)
         castPersistTask?.cancel()
         castPersistTask = Task { [ledger] in
             try? await Task.sleep(for: .milliseconds(500))
@@ -202,6 +203,123 @@ final class RemoteStore: ObservableObject {
             await CastCache.save(ledger)
         }
     }
+
+    // MARK: - Live composer streaming (the "composer.typing" channel)
+
+    /// The live remote typer per session (mesh composer streaming) — folded from
+    /// `composer.typing` casts, *other* devices only (this phone's own typing, republished by
+    /// the session's host, is skipped so the typer never locks itself). The session detail
+    /// locks its composer and renders the streamed draft while an entry is present;
+    /// expiry-guarded locally so a typer that vanished without its tombstone can't leave the
+    /// composer locked.
+    @Published private(set) var composerTypingBySession: [SessionID: ComposerTypingState] = [:]
+    /// Watcher-side expiry timers for `composerTypingBySession` (the crash guard).
+    private var composerExpiryTasks: [SessionID: Task<Void, Never>] = [:]
+    /// Sender-side throttle + idle bookkeeping for streaming THIS device's drafts: the
+    /// trailing-edge send, the last send time, the newest not-yet-sent draft, the idle-stop
+    /// timer, and which sessions have an active report out (so `ended` sends exactly one stop).
+    private var composerSendTasks: [SessionID: Task<Void, Never>] = [:]
+    private var composerLastSentAt: [SessionID: Date] = [:]
+    private var composerPendingText: [SessionID: String] = [:]
+    private var composerIdleTasks: [SessionID: Task<Void, Never>] = [:]
+    private var composerStreamingSessions: Set<SessionID> = []
+
+    /// The composer's draft for `sessionID` changed on this phone — report it (throttled) to
+    /// the session's host, which republishes it on the `composer.typing` channel for the rest
+    /// of the mesh, and (re)arm the idle stop. An emptied field ends the typing immediately.
+    /// A no-op toward a host that never advertised `canStreamComposer` (an older host would
+    /// throw on the unknown tag).
+    func composerDraftChanged(_ sessionID: SessionID, text: String) {
+        guard !demoMode else { return }
+        guard !text.isEmpty else { composerDraftEnded(sessionID); return }
+        guard let conn = connection(owningSession: sessionID), conn.connectivity.isLive,
+              conn.capabilities.canStreamComposer else { return }
+        composerPendingText[sessionID] = text
+        scheduleComposerIdleStop(sessionID)
+        guard composerSendTasks[sessionID] == nil else { return }  // trailing edge armed
+        let elapsed = Date().timeIntervalSince(composerLastSentAt[sessionID] ?? .distantPast)
+        let delay = max(0, ComposerTypingState.minPublishInterval - elapsed)
+        composerSendTasks[sessionID] = Task { [weak self] in
+            if delay > 0 { try? await Task.sleep(for: .seconds(delay)) }
+            guard !Task.isCancelled else { return }
+            self?.flushComposerDraft(sessionID)
+        }
+    }
+
+    /// Typing for `sessionID` finished on this phone — sent, cleared, or the detail closed.
+    /// Sends the stop that tombstones the session's entry (the host also idle-stops on its own
+    /// after `idleTimeout`, so a phone that vanishes still unlocks everyone).
+    func composerDraftEnded(_ sessionID: SessionID) {
+        composerSendTasks[sessionID]?.cancel()
+        composerSendTasks[sessionID] = nil
+        composerPendingText[sessionID] = nil
+        composerIdleTasks[sessionID]?.cancel()
+        composerIdleTasks[sessionID] = nil
+        composerLastSentAt[sessionID] = nil
+        guard composerStreamingSessions.remove(sessionID) != nil else { return }
+        connection(owningSession: sessionID)?.send(
+            .composerTyping(WireComposerTyping(sessionID: sessionID, text: "", active: false)))
+    }
+
+    /// One throttle-window flush: report the newest pending draft to the session's host.
+    private func flushComposerDraft(_ sessionID: SessionID) {
+        composerSendTasks[sessionID] = nil
+        guard let text = composerPendingText.removeValue(forKey: sessionID),
+              let conn = connection(owningSession: sessionID), conn.connectivity.isLive
+        else { return }
+        composerLastSentAt[sessionID] = Date()
+        composerStreamingSessions.insert(sessionID)
+        conn.send(.composerTyping(WireComposerTyping(sessionID: sessionID, text: text, active: true)))
+    }
+
+    /// Re-arm the typer-side idle stop: `idleTimeout` with no keystrokes ends the typing.
+    private func scheduleComposerIdleStop(_ sessionID: SessionID) {
+        composerIdleTasks[sessionID]?.cancel()
+        composerIdleTasks[sessionID] = Task { [weak self] in
+            try? await Task.sleep(for: .seconds(ComposerTypingState.idleTimeout))
+            guard !Task.isCancelled else { return }
+            self?.composerDraftEnded(sessionID)
+        }
+    }
+
+    /// Fold composer-typing casts into the watcher projection: fresh entries from other
+    /// devices lock (and render into) that session's composer; tombstones — and local expiry,
+    /// for a typer that vanished without one — unlock it.
+    private func updateComposerTyping(_ casts: [WireCast]) {
+        for cast in casts where cast.channel == MeshCastChannel.composerTyping {
+            guard let state = ComposerTypingState.decode(cast) else { continue }
+            if cast.deleted {
+                guard composerTypingBySession[state.sessionID]?.deviceID == state.deviceID
+                else { continue }
+                composerTypingBySession[state.sessionID] = nil
+                composerExpiryTasks[state.sessionID]?.cancel()
+                composerExpiryTasks[state.sessionID] = nil
+                continue
+            }
+            // Own typing (republished by the session's host under this phone's deviceID)
+            // never locks this composer; an entry already past its window (a catch-up
+            // replay) never locks at all.
+            guard state.deviceID != IdentityStore.deviceID(),
+                  state.isFresh(at: Date()) else { continue }
+            composerTypingBySession[state.sessionID] = state
+            scheduleComposerExpiry(state.sessionID, publishedAt: state.at)
+        }
+    }
+
+    /// Arm (or re-arm) the watcher-side expiry for a session's typing entry.
+    private func scheduleComposerExpiry(_ sessionID: SessionID, publishedAt: Date) {
+        composerExpiryTasks[sessionID]?.cancel()
+        let deadline = publishedAt.addingTimeInterval(ComposerTypingState.staleTimeout)
+        let delay = max(0, deadline.timeIntervalSinceNow)
+        composerExpiryTasks[sessionID] = Task { [weak self] in
+            try? await Task.sleep(for: .seconds(delay))
+            guard !Task.isCancelled, let self else { return }
+            guard let entry = self.composerTypingBySession[sessionID],
+                  !entry.isFresh(at: Date()) else { return }
+            self.composerTypingBySession[sessionID] = nil
+            self.composerExpiryTasks[sessionID] = nil
+        }
+    }
     private var transcriptPersistTask: Task<Void, Never>?
     @Published private(set) var capabilities = WireCapabilities(canModifyToolInput: false, allowAlwaysScopes: [])
     @Published private(set) var grantedScope: DeviceScope = .approve
@@ -2002,7 +2120,11 @@ final class RemoteStore: ObservableObject {
              .intelligenceResult, .credentialManifest, .credentialProvision, .createProject,
              // Cast subscriptions are per-connection (each `HostConnection` subscribes on its
              // own ready, with the merged ledger's cursors) — nothing routes them here.
-             .castSubscribe:
+             .castSubscribe,
+             // Composer typing goes straight to the owning connection from
+             // `composerDraftChanged`/`flushComposerDraft` — ephemeral by design, it must
+             // never be queued for optimistic replay, so it skips this router entirely.
+             .composerTyping:
             break
         }
     }
@@ -2195,7 +2317,10 @@ final class RemoteStore: ObservableObject {
              // Remote project creation (CLOUD_RUNTIME §4.3) — demo has no host to clone on.
              .createProject,
              // Mesh casting (demo has no host to cast).
-             .castSubscribe:
+             .castSubscribe,
+             // Live composer streaming — demo has no other devices to stream to, and
+             // `composerDraftChanged` already no-ops in demo mode before routing.
+             .composerTyping:
             break  // passive / already handled by the seeded fixtures (demo has no mesh peers)
         }
     }

NucleicRemote/NucleicRemote/Views/SessionDetailView.swift

@@ -40,6 +40,18 @@ struct SessionDetailView: View {
         store.sessions.first { $0.sessionID == sessionID }
     }
 
+    /// Another device's live typing in this chat's composer (mesh composer streaming). While
+    /// present, this composer is locked and renders the streamed draft; it unlocks when the
+    /// typer sends or goes idle (their tombstone — or the local expiry guard — clears it).
+    private var remoteTyping: ComposerTypingState? {
+        store.composerTypingBySession[sessionID]
+    }
+
+    /// The friendly label for a remote typer, never blank.
+    private func typerName(_ typing: ComposerTypingState) -> String {
+        typing.deviceName.isEmpty ? "Another device" : typing.deviceName
+    }
+
     var body: some View {
         // The detail's height comes from the enclosing GeometryReader — a value fixed by the parent
         // (the navigation content area), never by anything inside it. The attention cards (approval /
@@ -101,9 +113,43 @@ struct SessionDetailView: View {
                 .onChange(of: proxy.size.height, initial: true) { _, height in
                     availableHeight = height
                 }
+                // Stream this composer's draft to the session's host (throttled in the store)
+                // so every other device viewing this chat sees it live and locks its own
+                // composer; an emptied field — including the clear on send — ends the typing
+                // and unlocks them. Leaving the detail ends it too.
+                .onChange(of: draft) { _, text in
+                    store.composerDraftChanged(sessionID, text: text)
+                }
+                .onDisappear { store.composerDraftEnded(sessionID) }
         }
     }
 
+    /// The live view of another device's in-progress draft for this chat, shown above the
+    /// (locked) field. Head-truncated: the tail is where the typing is happening, so it's the
+    /// part that must stay visible.
+    private func remoteTypingRow(_ typing: ComposerTypingState) -> some View {
+        VStack(alignment: .leading, spacing: 4) {
+            HStack(spacing: 6) {
+                Image(systemName: "ellipsis.bubble")
+                Text("\(typerName(typing)) is typing…")
+                Spacer(minLength: 0)
+            }
+            .font(.footnote.weight(.semibold))
+            .foregroundStyle(Palette.accent)
+            if !typing.text.isEmpty {
+                Text(typing.text)
+                    .font(.footnote)
+                    .foregroundStyle(.secondary)
+                    .lineLimit(3)
+                    .truncationMode(.head)
+                    .frame(maxWidth: .infinity, alignment: .leading)
+            }
+        }
+        .frame(maxWidth: .infinity, alignment: .leading)
+        .padding(.horizontal, 8).padding(.vertical, 6)
+        .background(.quaternary.opacity(0.4), in: .rect(cornerRadius: 10))
+    }
+
     /// ⌘. interrupts a running session (the Mac's "stop" convention) — the action is otherwise
     /// only in the ⋯ menu. A hidden button carries the shortcut; present only when it applies.
     @ViewBuilder
@@ -409,6 +455,12 @@ struct SessionDetailView: View {
                         }
                         if store.canControl, let summary { controlRow(summary) }
                         if canCompose {
+                            // Someone is typing in this chat on another device: their draft
+                            // streams in live here while the field below is locked (one typer
+                            // per session at a time, mirroring the Mac composer).
+                            if let typing = remoteTyping {
+                                remoteTypingRow(typing)
+                            }
                             // Staged attachments ride above the field, matching the queued-message
                             // chips and the Mac composer.
                             if !attachments.isEmpty {
@@ -430,11 +482,16 @@ struct SessionDetailView: View {
                                 // No keyboard-accessory Done button here (it floats awkwardly
                                 // over the glass bar on iOS 26) — a drag on the transcript
                                 // dismisses the keyboard instead (`scrollDismissesKeyboard`).
-                                TextField(running ? "Queue a follow-up…" : "Send a follow-up…",
-                                          text: $draft, axis: .vertical)
+                                TextField(
+                                    remoteTyping.map { "\(typerName($0)) is typing…" }
+                                        ?? (running ? "Queue a follow-up…" : "Send a follow-up…"),
+                                    text: $draft, axis: .vertical)
                                     .textFieldStyle(.plain)
                                     .lineLimit(1...4)
                                     .padding(.vertical, 3)
+                                    // Locked while another device is typing here — the
+                                    // mesh-wide "one typer per session" contract.
+                                    .disabled(remoteTyping != nil)
                                 // Stop the in-flight turn (the Mac's ⌘. / "Interrupt"). Shown only
                                 // while running and at control scope; send stays at the far right so
                                 // its position never shifts. Mirrors `interruptShortcut`.
@@ -458,8 +515,10 @@ struct SessionDetailView: View {
                                     Image(systemName: "arrow.up.circle.fill")
                                         .font(.title2)
                                 }
-                                // An attachment-only follow-up (files, no typed text) is sendable.
-                                .disabled((draft.trimmingCharacters(in: .whitespaces).isEmpty && attachments.isEmpty) || !store.connectivity.isLive)
+                                // An attachment-only follow-up (files, no typed text) is sendable —
+                                // but never while another device is mid-draft here (locked).
+                                .disabled((draft.trimmingCharacters(in: .whitespaces).isEmpty && attachments.isEmpty)
+                                    || !store.connectivity.isLive || remoteTyping != nil)
                                 // Hardware-keyboard send (Magic Keyboard on iPad), mirroring the
                                 // Mac — plain Return stays newline in the multiline field.
                                 .keyboardShortcut(.return, modifiers: .command)