WIP: Compose interaction mode

Cotabby.xcodeproj/project.pbxproj

@@ -35,6 +35,7 @@
 		E10000052F93000100DDD005 /* DisplayCoordinateConverterTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = E10000152F93000100DDD015 /* DisplayCoordinateConverterTests.swift */; };
 		F10000012FA0000100EEE001 /* TextDirectionDetectorTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = F10000112FA0000100EEE011 /* TextDirectionDetectorTests.swift */; };
 		G10000012FB0000100FFF001 /* WordCountFormatterTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = G10000112FB0000100FFF011 /* WordCountFormatterTests.swift */; };
+		H10000012FC0000100GGG001 /* ComposeContextNormalizerTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = H10000112FC0000100GGG011 /* ComposeContextNormalizerTests.swift */; };
 /* End PBXBuildFile section */
 
 /* Begin PBXContainerItemProxy section */
@@ -73,6 +74,7 @@
 		F29623C5C0A67B992D383A3C /* LlamaPromptRendererTests.swift */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = sourcecode.swift; path = LlamaPromptRendererTests.swift; sourceTree = "<group>"; };
 		F9D35DB9E86506B9FAE1CFE9 /* ModelFileValidatorTests.swift */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = sourcecode.swift; path = ModelFileValidatorTests.swift; sourceTree = "<group>"; };
 		G10000112FB0000100FFF011 /* WordCountFormatterTests.swift */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = sourcecode.swift; path = WordCountFormatterTests.swift; sourceTree = "<group>"; };
+		H10000112FC0000100GGG011 /* ComposeContextNormalizerTests.swift */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = sourcecode.swift; path = ComposeContextNormalizerTests.swift; sourceTree = "<group>"; };
 
 /* End PBXFileReference section */
 
@@ -150,6 +152,7 @@
 				G20000112FB0000100FFF011 /* ClipboardRelevanceFilterTests.swift */,
 				G10000122FB0000100FFF012 /* ClipboardContentDistillerTests.swift */,
 				G10000112FB0000100FFF011 /* WordCountFormatterTests.swift */,
+				H10000112FC0000100GGG011 /* ComposeContextNormalizerTests.swift */,
 			);
 			path = CotabbyTests;
 			sourceTree = "<group>";
@@ -293,6 +296,7 @@
 				G20000012FB0000100FFF001 /* ClipboardRelevanceFilterTests.swift in Sources */,
 				G10000022FB0000100FFF002 /* ClipboardContentDistillerTests.swift in Sources */,
 				G10000012FB0000100FFF001 /* WordCountFormatterTests.swift in Sources */,
+				H10000012FC0000100GGG001 /* ComposeContextNormalizerTests.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};

Cotabby/App/Coordinators/SuggestionCoordinator+Input.swift

@@ -14,6 +14,7 @@ extension SuggestionCoordinator {
         if SuggestionAvailabilityEvaluator.shouldSchedulePrediction(
             globallyEnabled: settingsSnapshot.isGloballyEnabled,
             disabledAppBundleIdentifiers: settingsSnapshot.disabledAppBundleIdentifiers,
+            interactionMode: settingsSnapshot.selectedInteractionMode,
             inputMonitoringGranted: permissionManager.inputMonitoringGranted,
             screenRecordingGranted: permissionManager.screenRecordingGranted,
             focusSnapshot: focusModel.snapshot
@@ -42,6 +43,7 @@ extension SuggestionCoordinator {
         if let disabledReason = SuggestionAvailabilityEvaluator.disabledReason(
             globallyEnabled: settingsSnapshot.isGloballyEnabled,
             disabledAppBundleIdentifiers: settingsSnapshot.disabledAppBundleIdentifiers,
+            interactionMode: settingsSnapshot.selectedInteractionMode,
             inputMonitoringGranted: permissionManager.inputMonitoringGranted,
             screenRecordingGranted: permissionManager.screenRecordingGranted,
             focusSnapshot: snapshot
@@ -87,6 +89,7 @@ extension SuggestionCoordinator {
         if let disabledReason = SuggestionAvailabilityEvaluator.disabledReason(
             globallyEnabled: settingsSnapshot.isGloballyEnabled,
             disabledAppBundleIdentifiers: settingsSnapshot.disabledAppBundleIdentifiers,
+            interactionMode: settingsSnapshot.selectedInteractionMode,
             inputMonitoringGranted: permissionManager.inputMonitoringGranted,
             screenRecordingGranted: permissionManager.screenRecordingGranted,
             focusSnapshot: focusModel.snapshot
@@ -103,7 +106,7 @@ extension SuggestionCoordinator {
             return acceptEntireSuggestion()
         }
 
-        if let activeSession = interactionState.activeSession {
+        if let activeSession = interactionState.activeAutocompleteSession {
             return handleInputEvent(event, with: activeSession)
         }
 

Cotabby/App/Coordinators/SuggestionCoordinator+Lifecycle.swift

@@ -83,6 +83,7 @@ extension SuggestionCoordinator {
         if SuggestionAvailabilityEvaluator.shouldSchedulePrediction(
             globallyEnabled: settingsSnapshot.isGloballyEnabled,
             disabledAppBundleIdentifiers: settingsSnapshot.disabledAppBundleIdentifiers,
+            interactionMode: settingsSnapshot.selectedInteractionMode,
             inputMonitoringGranted: permissionManager.inputMonitoringGranted,
             screenRecordingGranted: permissionManager.screenRecordingGranted,
             focusSnapshot: focusModel.snapshot

Cotabby/App/Coordinators/SuggestionCoordinator+Prediction.swift

@@ -8,6 +8,11 @@
     // MARK: - Prediction Pipeline
 
     func schedulePrediction() {
+        guard settingsSnapshot.selectedInteractionMode == .autocomplete else {
+            disablePredictionsPreservingVisualContext(reason: composeModePendingReason)
+            return
+        }
+
         if let disabledReason = SuggestionAvailabilityEvaluator.disabledReason(
             globallyEnabled: settingsSnapshot.isGloballyEnabled,
             disabledAppBundleIdentifiers: settingsSnapshot.disabledAppBundleIdentifiers,
@@ -32,7 +37,12 @@
     }
 
     /// Refreshes focus after debounce, materializes a stable context, and starts generation.
     func generateFromCurrentFocus(workID: UInt64) async {
+        guard settingsSnapshot.selectedInteractionMode == .autocomplete else {
+            disablePredictionsPreservingVisualContext(reason: composeModePendingReason)
+            return
+        }
+
         guard workController.isCurrent(workID) else {
             return
         }
@@ -276,7 +286,7 @@
     /// This is the heart of partial acceptance: a text change is not automatically "stale" anymore.
     /// It may instead mean "the user consumed the next expected part of the suggestion."
     func reconcileActiveSession(with snapshot: FocusSnapshot) {
-        guard interactionState.activeSession != nil else {
+        guard interactionState.activeAutocompleteSession != nil else {
             if overlayState.isVisible {
                 hideOverlay(reason: "Overlay hidden because no ready suggestion remains.")
             }
@@ -426,6 +436,10 @@
     /// Once screenshot context becomes ready, regenerate only if the user is still in the same
     /// field and there is enough typed text for a real inline completion request.
     func schedulePredictionForCurrentFocusIfPossible(matching identity: FocusedInputIdentity) {
+        guard settingsSnapshot.selectedInteractionMode == .autocomplete else {
+            return
+        }
+
         focusModel.refreshNow()
         let snapshot = focusModel.snapshot
 
@@ -438,4 +452,8 @@
 
         schedulePrediction()
     }
+
+    private var composeModePendingReason: String {
+        "Compose Mode is selected. Draft generation will be enabled after the Compose request pipeline is installed."
+    }
 }

Cotabby/App/Coordinators/SuggestionCoordinator.swift

@@ -44,6 +44,7 @@ final class SuggestionCoordinator: ObservableObject {
     let clipboardContextProvider: any ClipboardContextProviding
     let clipboardRelevanceFilter: any ClipboardRelevanceFiltering
     let visualContextCoordinator: any VisualContextCoordinating
+    let composeContextCollector: ComposeContextCollector
     let interactionState: SuggestionInteractionState
     let workController: SuggestionWorkController
     let configuration: SuggestionConfiguration
@@ -73,6 +74,7 @@ final class SuggestionCoordinator: ObservableObject {
         clipboardContextProvider: any ClipboardContextProviding,
         clipboardRelevanceFilter: any ClipboardRelevanceFiltering,
         visualContextCoordinator: any VisualContextCoordinating,
+        composeContextCollector: ComposeContextCollector,
         interactionState: SuggestionInteractionState,
         workController: SuggestionWorkController,
         configuration: SuggestionConfiguration,
@@ -91,6 +93,7 @@ final class SuggestionCoordinator: ObservableObject {
         self.clipboardContextProvider = clipboardContextProvider
         self.clipboardRelevanceFilter = clipboardRelevanceFilter
         self.visualContextCoordinator = visualContextCoordinator
+        self.composeContextCollector = composeContextCollector
         self.interactionState = interactionState
         self.workController = workController
         self.configuration = configuration

Cotabby/App/Core/CotabbyAppEnvironment.swift

@@ -103,6 +103,8 @@ final class CotabbyAppEnvironment {
             screenshotContextGenerator: screenshotContextGenerator,
             screenRecordingPermissionProvider: { permissionManager.screenRecordingGranted }
         )
+        let composeContextCollector = ComposeContextCollector()
+
         let foundationModelEngine: any SuggestionGenerating
         #if canImport(FoundationModels)
         if #available(macOS 26.0, *) {
@@ -123,14 +125,15 @@ final class CotabbyAppEnvironment {
         TabbyLogger.app.info("Foundation model engine unavailable (SDK)")
         #endif
 
+        let llamaEngine = LlamaSuggestionEngine(runtimeManager: runtimeManager)
         let mlxEngine: any SuggestionGenerating = MLXSuggestionEngine(
             runtimeManager: mlxRuntimeManager
         )
 
         let suggestionEngine: any SuggestionGenerating = SuggestionEngineRouter(
             suggestionSettings: suggestionSettings,
             foundationModelEngine: foundationModelEngine,
-            llamaEngine: LlamaSuggestionEngine(runtimeManager: runtimeManager),
+            llamaEngine: llamaEngine,
             mlxEngine: mlxEngine
         )
 
@@ -147,6 +150,7 @@ final class CotabbyAppEnvironment {
             clipboardContextProvider: clipboardContextProvider,
             clipboardRelevanceFilter: clipboardRelevanceFilter,
             visualContextCoordinator: visualContextCoordinator,
+            composeContextCollector: composeContextCollector,
             interactionState: interactionState,
             workController: workController,
             configuration: configuration

Cotabby/Models/LlamaRuntimeModels.swift

@@ -138,6 +138,12 @@ struct RemoteModelFile: Equatable, Hashable, Sendable {
 }
 
 enum RuntimeModelCatalog {
+    static let composeRequiredFilename = "gemma-3n-E4B-it-Q4_K_M.gguf"
+
+    static func supportsCompose(filename: String?) -> Bool {
+        filename == composeRequiredFilename
+    }
+
     static func displayName(for filename: String) -> String {
         switch filename {
         case "Qwen3-0.6B-Q4_K_M.gguf":

Cotabby/Models/SuggestionEngineModels.swift

@@ -1,12 +1,40 @@
 import Foundation
 
 /// File overview:
-/// Defines the product-facing engine choices for Cotabby's autocomplete pipeline.
+/// Defines the product-facing writing mode and engine choices for Cotabby's suggestion pipeline.
 /// This file exists because "which engine is active?" is a domain concept, not a UI-only detail.
+/// The same applies to the interaction mode: runtime code needs an immutable value that says
+/// whether Cotabby is completing a short inline tail or preparing for a deliberate full draft.
 ///
 /// The important architectural distinction is:
-/// - a local GGUF file is a model option inside the llama runtime
+/// - autocomplete vs. compose is an interaction contract
+/// - a local GGUF/MLX file is a model option inside its respective runtime
 /// - Apple Intelligence vs. local llama vs. MLX is an engine choice above the runtime layer
+enum SuggestionInteractionMode: String, CaseIterable, Equatable, Hashable, Sendable, Identifiable {
+    case autocomplete
+    case compose
+
+    var id: String { rawValue }
+
+    var displayLabel: String {
+        switch self {
+        case .autocomplete:
+            return "Autocomplete"
+        case .compose:
+            return "Compose"
+        }
+    }
+
+    var explanatoryText: String {
+        switch self {
+        case .autocomplete:
+            return "Predicts a short inline continuation near the caret."
+        case .compose:
+            return "Prepares a full draft for deliberate review before typing."
+        }
+    }
+}
+
 enum SuggestionEngineKind: String, CaseIterable, Equatable, Hashable, Sendable, Identifiable {
     case appleIntelligence
     case llamaOpenSource
@@ -63,13 +91,45 @@
 struct SuggestionSettingsSnapshot: Equatable, Sendable {
     let isGloballyEnabled: Bool
     let disabledAppBundleIdentifiers: Set<String>
+    let selectedInteractionMode: SuggestionInteractionMode
     let selectedEngine: SuggestionEngineKind
     let selectedWordCountPreset: SuggestionWordCountPreset
     let isClipboardContextEnabled: Bool
     /// User-authored profile data for Cotabby's single instruction-rendered completion prompt.
     /// This travels in the snapshot so generation uses the same value the Settings UI shows.
     let userName: String
+    /// Optional user-authored tags used by Compose Mode prompts.
+    /// Currently always empty; the model does not yet surface a tag editor, but Compose's prompt
+    /// renderer reads this field so future tagging UI can land without re-plumbing.
+    let userTags: [String]
     let debounceMilliseconds: Int
     let focusPollIntervalMilliseconds: Int
     let isMultiLineEnabled: Bool
+
+    // swiftlint:disable:next function_parameter_count
+    init(
+        isGloballyEnabled: Bool,
+        disabledAppBundleIdentifiers: Set<String>,
+        selectedInteractionMode: SuggestionInteractionMode = .autocomplete,
+        selectedEngine: SuggestionEngineKind,
+        selectedWordCountPreset: SuggestionWordCountPreset,
+        isClipboardContextEnabled: Bool,
+        userName: String,
+        userTags: [String] = [],
+        debounceMilliseconds: Int,
+        focusPollIntervalMilliseconds: Int,
+        isMultiLineEnabled: Bool = false
+    ) {
+        self.isGloballyEnabled = isGloballyEnabled
+        self.disabledAppBundleIdentifiers = disabledAppBundleIdentifiers
+        self.selectedInteractionMode = selectedInteractionMode
+        self.selectedEngine = selectedEngine
+        self.selectedWordCountPreset = selectedWordCountPreset
+        self.isClipboardContextEnabled = isClipboardContextEnabled
+        self.userName = userName
+        self.userTags = userTags
+        self.debounceMilliseconds = debounceMilliseconds
+        self.focusPollIntervalMilliseconds = focusPollIntervalMilliseconds
+        self.isMultiLineEnabled = isMultiLineEnabled
+    }
 }