Route pending settings through initialisation choices

src/common/messages/combinedMessages.prod.ts

@@ -11715,6 +11715,72 @@ export const allMessages: Readonly<Record<string, Readonly<Record<string, string
         zh: "覆盖",
         "zh-tw": "覆寫",
     },
+    "Ui.SetupWizard.ApplySettingsInitialisation.ApplyWithoutInitialisation": {
+        def: "Apply without Initialisation",
+    },
+    "Ui.SetupWizard.ApplySettingsInitialisation.Back": {
+        def: "Review another way to apply these settings",
+    },
+    "Ui.SetupWizard.ApplySettingsInitialisation.BypassGuidance": {
+        def: "Applying these settings alone can make this device incompatible with its existing synchronisation data. Use this only when you have confirmed that reconstruction is unnecessary.",
+    },
+    "Ui.SetupWizard.ApplySettingsInitialisation.BypassTitle": {
+        def: "Apply Settings without Initialisation?",
+    },
+    "Ui.SetupWizard.ApplySettingsInitialisation.ContinueFetch": {
+        def: "Continue with Fetch",
+    },
+    "Ui.SetupWizard.ApplySettingsInitialisation.FetchOption": {
+        def: "Reset Synchronisation on This Device",
+    },
+    "Ui.SetupWizard.ApplySettingsInitialisation.FetchOptionDesc": {
+        def: "After restarting, rebuild this device's local database from the current remote synchronisation data. Files in the Vault will then be reconciled with that data.",
+    },
+    "Ui.SetupWizard.ApplySettingsInitialisation.FetchOptionP2PDesc": {
+        def: "After restarting, select an online source device. This device's local LiveSync database will be rebuilt from that source.",
+    },
+    "Ui.SetupWizard.ApplySettingsInitialisation.Guidance": {
+        def: "These setting changes alter how synchronisation data is interpreted. Apply them together with an initialisation operation after restart.",
+    },
+    "Ui.SetupWizard.ApplySettingsInitialisation.KeepEditing": {
+        def: "Keep Editing",
+    },
+    "Ui.SetupWizard.ApplySettingsInitialisation.ProceedFetch": {
+        def: "Restart and Fetch Synchronisation Data",
+    },
+    "Ui.SetupWizard.ApplySettingsInitialisation.ProceedFetchP2P": {
+        def: "Restart and Select a Source Device",
+    },
+    "Ui.SetupWizard.ApplySettingsInitialisation.ProceedRebuild": {
+        def: "Restart and Overwrite Server Data",
+    },
+    "Ui.SetupWizard.ApplySettingsInitialisation.ProceedRebuildP2P": {
+        def: "Restart and Prepare This Device",
+    },
+    "Ui.SetupWizard.ApplySettingsInitialisation.Question": {
+        def: "Which existing data should be used after restart?",
+    },
+    "Ui.SetupWizard.ApplySettingsInitialisation.RebuildOption": {
+        def: "Overwrite Server Data with This Device's Files",
+    },
+    "Ui.SetupWizard.ApplySettingsInitialisation.RebuildOptionDesc": {
+        def: "Rebuild the local and remote databases from the files currently in this Vault. Other synchronising devices must reset their local synchronisation afterwards.",
+    },
+    "Ui.SetupWizard.ApplySettingsInitialisation.RebuildOptionP2P": {
+        def: "Prepare This Device from This Vault",
+    },
+    "Ui.SetupWizard.ApplySettingsInitialisation.RebuildOptionP2PDesc": {
+        def: "Rebuild this device's local LiveSync database from the files currently in this Vault. This does not overwrite another device.",
+    },
+    "Ui.SetupWizard.ApplySettingsInitialisation.RemoteVerificationGuidance": {
+        def: "The configured remote could not be verified with the current credentials and encryption settings. Continuing may make the Fetch fail after restart.",
+    },
+    "Ui.SetupWizard.ApplySettingsInitialisation.RemoteVerificationTitle": {
+        def: "Remote Synchronisation Data Could Not Be Verified",
+    },
+    "Ui.SetupWizard.ApplySettingsInitialisation.Title": {
+        def: "Apply Settings and Reinitialise Synchronisation",
+    },
     "Ui.SetupWizard.Common.Back": {
         def: "No, please take me back",
         es: "No, volver atrás",

src/common/messagesJson/en.json

@@ -1321,6 +1321,28 @@
     "Ui.Settings.SyncSettings.Fetch": "Fetch",
     "Ui.Settings.SyncSettings.Merge": "Merge",
     "Ui.Settings.SyncSettings.Overwrite": "Overwrite",
+    "Ui.SetupWizard.ApplySettingsInitialisation.ApplyWithoutInitialisation": "Apply without Initialisation",
+    "Ui.SetupWizard.ApplySettingsInitialisation.Back": "Review another way to apply these settings",
+    "Ui.SetupWizard.ApplySettingsInitialisation.BypassGuidance": "Applying these settings alone can make this device incompatible with its existing synchronisation data. Use this only when you have confirmed that reconstruction is unnecessary.",
+    "Ui.SetupWizard.ApplySettingsInitialisation.BypassTitle": "Apply Settings without Initialisation?",
+    "Ui.SetupWizard.ApplySettingsInitialisation.ContinueFetch": "Continue with Fetch",
+    "Ui.SetupWizard.ApplySettingsInitialisation.FetchOption": "Reset Synchronisation on This Device",
+    "Ui.SetupWizard.ApplySettingsInitialisation.FetchOptionDesc": "After restarting, rebuild this device's local database from the current remote synchronisation data. Files in the Vault will then be reconciled with that data.",
+    "Ui.SetupWizard.ApplySettingsInitialisation.FetchOptionP2PDesc": "After restarting, select an online source device. This device's local LiveSync database will be rebuilt from that source.",
+    "Ui.SetupWizard.ApplySettingsInitialisation.Guidance": "These setting changes alter how synchronisation data is interpreted. Apply them together with an initialisation operation after restart.",
+    "Ui.SetupWizard.ApplySettingsInitialisation.KeepEditing": "Keep Editing",
+    "Ui.SetupWizard.ApplySettingsInitialisation.ProceedFetch": "Restart and Fetch Synchronisation Data",
+    "Ui.SetupWizard.ApplySettingsInitialisation.ProceedFetchP2P": "Restart and Select a Source Device",
+    "Ui.SetupWizard.ApplySettingsInitialisation.ProceedRebuild": "Restart and Overwrite Server Data",
+    "Ui.SetupWizard.ApplySettingsInitialisation.ProceedRebuildP2P": "Restart and Prepare This Device",
+    "Ui.SetupWizard.ApplySettingsInitialisation.Question": "Which existing data should be used after restart?",
+    "Ui.SetupWizard.ApplySettingsInitialisation.RebuildOption": "Overwrite Server Data with This Device's Files",
+    "Ui.SetupWizard.ApplySettingsInitialisation.RebuildOptionDesc": "Rebuild the local and remote databases from the files currently in this Vault. Other synchronising devices must reset their local synchronisation afterwards.",
+    "Ui.SetupWizard.ApplySettingsInitialisation.RebuildOptionP2P": "Prepare This Device from This Vault",
+    "Ui.SetupWizard.ApplySettingsInitialisation.RebuildOptionP2PDesc": "Rebuild this device's local LiveSync database from the files currently in this Vault. This does not overwrite another device.",
+    "Ui.SetupWizard.ApplySettingsInitialisation.RemoteVerificationGuidance": "The configured remote could not be verified with the current credentials and encryption settings. Continuing may make the Fetch fail after restart.",
+    "Ui.SetupWizard.ApplySettingsInitialisation.RemoteVerificationTitle": "Remote Synchronisation Data Could Not Be Verified",
+    "Ui.SetupWizard.ApplySettingsInitialisation.Title": "Apply Settings and Reinitialise Synchronisation",
     "Ui.SetupWizard.Common.Back": "No, please take me back",
     "Ui.SetupWizard.Common.Cancel": "Cancel",
     "Ui.SetupWizard.Common.ProceedSelectOption": "Please select an option to proceed",

src/common/messagesYAML/en.yaml

@@ -2309,6 +2309,29 @@ Ui:
             Fetch: Fetch
             Overwrite: Overwrite
     SetupWizard:
+        ApplySettingsInitialisation:
+            ApplyWithoutInitialisation: Apply without Initialisation
+            Back: Review another way to apply these settings
+            BypassGuidance: Applying these settings alone can make this device incompatible with its existing synchronisation data. Use this only when you have confirmed that reconstruction is unnecessary.
+            BypassTitle: Apply Settings without Initialisation?
+            ContinueFetch: Continue with Fetch
+            FetchOption: Reset Synchronisation on This Device
+            FetchOptionDesc: After restarting, rebuild this device's local database from the current remote synchronisation data. Files in the Vault will then be reconciled with that data.
+            FetchOptionP2PDesc: After restarting, select an online source device. This device's local LiveSync database will be rebuilt from that source.
+            Guidance: These setting changes alter how synchronisation data is interpreted. Apply them together with an initialisation operation after restart.
+            KeepEditing: Keep Editing
+            ProceedFetch: Restart and Fetch Synchronisation Data
+            ProceedFetchP2P: Restart and Select a Source Device
+            ProceedRebuild: Restart and Overwrite Server Data
+            ProceedRebuildP2P: Restart and Prepare This Device
+            Question: Which existing data should be used after restart?
+            RebuildOption: Overwrite Server Data with This Device's Files
+            RebuildOptionDesc: Rebuild the local and remote databases from the files currently in this Vault. Other synchronising devices must reset their local synchronisation afterwards.
+            RebuildOptionP2P: Prepare This Device from This Vault
+            RebuildOptionP2PDesc: Rebuild this device's local LiveSync database from the files currently in this Vault. This does not overwrite another device.
+            RemoteVerificationGuidance: The configured remote could not be verified with the current credentials and encryption settings. Continuing may make the Fetch fail after restart.
+            RemoteVerificationTitle: Remote Synchronisation Data Could Not Be Verified
+            Title: Apply Settings and Reinitialise Synchronisation
         Common:
             Back: No, please take me back
             Cancel: Cancel

src/modules/features/SettingDialogue/ObsidianLiveSyncSettingTab.declarative.unit.spec.ts

@@ -121,6 +121,10 @@ function isGroup(item: SettingDefinitionItem): item is SettingDefinitionGroup {
     return "type" in item && item.type === "group";
 }
 
+function isAction(item: SettingDefinitionItem): item is Extract<SettingDefinitionItem, { action: unknown }> {
+    return "action" in item && typeof item.action === "function";
+}
+
 function itemLabel(item: SettingDefinitionItem): string {
     if (isPage(item)) return item.name;
     if (isGroup(item)) return item.heading ?? "";
@@ -179,7 +183,7 @@ beforeEach(() => {
 describe("ObsidianLiveSyncSettingTab native page lifecycle", () => {
     it("keeps Quick Setup first while synchronisation is inactive and separates synchronisation pages from it", () => {
         const tab = createSettingsTab();
-        const definitions = tab.getSettingDefinitions();
+        const definitions = tab.getSettingDefinitions().filter(isGroup);
 
         expect(definitions.slice(0, 3).map(itemLabel)).toEqual([
             "🧙‍♂️ Quick Setup",
@@ -191,7 +195,7 @@ describe("ObsidianLiveSyncSettingTab native page lifecycle", () => {
     it("keeps the synchronisation group first and orders General Settings before Quick Setup while synchronisation is active", () => {
         const tab = createSettingsTab();
         tab.editingSettings.liveSync = true;
-        const definitions = tab.getSettingDefinitions();
+        const definitions = tab.getSettingDefinitions().filter(isGroup);
 
         expect(definitions.slice(0, 3).map(itemLabel)).toEqual([
             "🔄 Synchronisation",
@@ -200,6 +204,16 @@ describe("ObsidianLiveSyncSettingTab native page lifecycle", () => {
         ]);
     });
 
+    it("keeps the pending initialisation action visible on the root settings page", () => {
+        const tab = createSettingsTab();
+        tab.editingSettings.handleFilenameCaseSensitive = !tab.initialSettings!.handleFilenameCaseSensitive;
+
+        const action = tab.getSettingDefinitions().find(isAction);
+
+        expect(action?.name).toBe("Apply");
+        expect(typeof action?.visible === "function" ? action.visible() : action?.visible).toBe(true);
+    });
+
     it("keeps Remote Configuration and Sync Settings as native pages inside the Synchronisation group", () => {
         const tab = createSettingsTab();
         const definitions = tab.getSettingDefinitions();

src/modules/features/SettingDialogue/ObsidianLiveSyncSettingTab.ts

@@ -3,7 +3,6 @@ import {
     type ObsidianLiveSyncSettings,
     type RemoteDBSettings,
     LOG_LEVEL_NOTICE,
-    FlagFilesHumanReadable,
     REMOTE_COUCHDB,
     REMOTE_MINIO,
     type ConfigLevel,
@@ -79,6 +78,7 @@ import type {
 } from "obsidian";
 import { createExtraMenuSettingSpecGroup, createGeneralSettingSpecGroups } from "./GeneralSettingSpecs.ts";
 import { SetupManager } from "@/modules/features/SetupManager.ts";
+import { isP2PMainRemote } from "@/common/remoteConfiguration.ts";
 
 // For creating a document
 // const toc = new Set<string>();
@@ -907,10 +907,11 @@ export class ObsidianLiveSyncSettingTab extends PluginSettingTab {
         ]);
         const laterGroups = [setupOtherDevices, maintenance, extraFeatures, advancedSettings, helpAndInformation];
 
+        const pendingInitialisation = this.createRebuildRequiredAction();
         if (this.isAnySyncEnabled()) {
-            return [synchronisation, generalSettings, quickSetup, ...laterGroups];
+            return [pendingInitialisation, synchronisation, generalSettings, quickSetup, ...laterGroups];
         }
-        return [quickSetup, synchronisation, generalSettings, ...laterGroups];
+        return [pendingInitialisation, quickSetup, synchronisation, generalSettings, ...laterGroups];
     }
 
     private beginRenderScope(refresh: () => void): Component {
@@ -1031,50 +1032,53 @@ export class ObsidianLiveSyncSettingTab extends PluginSettingTab {
             Logger(`Passphrase is not valid, please fix it.`, LOG_LEVEL_NOTICE);
             return;
         }
-        const OPTION_FETCH = $msg("obsidianLiveSyncSettingTab.optionFetchFromRemote");
-        const OPTION_REBUILD_BOTH = $msg("obsidianLiveSyncSettingTab.optionRebuildBoth");
-        const OPTION_ONLY_SETTING = $msg("obsidianLiveSyncSettingTab.optionSaveOnlySettings");
-        const OPTION_CANCEL = $msg("obsidianLiveSyncSettingTab.optionCancel");
-        const title = $msg("obsidianLiveSyncSettingTab.titleRebuildRequired");
-        const note = $msg("obsidianLiveSyncSettingTab.msgRebuildRequired", {
-            OPTION_REBUILD_BOTH,
-            OPTION_FETCH,
-            OPTION_ONLY_SETTING,
+        const keepEditing = $msg("Ui.SetupWizard.ApplySettingsInitialisation.KeepEditing");
+        const setupManager = this.core.getModule(SetupManager);
+        const result = await setupManager.applySettingsWithInitialisationChoice({
+            isP2P: isP2PMainRemote(this.editingSettings),
+            validateChoice: async (mode) => {
+                if (mode !== "fetch" || (await this.checkWorkingPassphrase())) {
+                    return true;
+                }
+                const continueFetch = $msg("Ui.SetupWizard.ApplySettingsInitialisation.ContinueFetch");
+                return (
+                    (await this.core.confirm.confirmWithMessage(
+                        $msg("Ui.SetupWizard.ApplySettingsInitialisation.RemoteVerificationTitle"),
+                        $msg("Ui.SetupWizard.ApplySettingsInitialisation.RemoteVerificationGuidance"),
+                        [continueFetch, keepEditing],
+                        keepEditing
+                    )) === continueFetch
+                );
+            },
+            applySettings: async () => {
+                if (!this.editingSettings.encrypt) {
+                    this.editingSettings.passphrase = "";
+                }
+                await this.saveAllDirtySettings();
+            },
         });
-        const buttons = [
-            OPTION_FETCH,
-            OPTION_REBUILD_BOTH, // OPTION_REBUILD_REMOTE,
-            OPTION_ONLY_SETTING,
-            OPTION_CANCEL,
-        ];
-        const result = await this.core.confirm.confirmWithMessage(title, note, buttons, OPTION_CANCEL);
-        if (result == OPTION_CANCEL) return;
-        if (result == OPTION_FETCH) {
-            if (!(await this.checkWorkingPassphrase())) {
-                if (
-                    (await this.core.confirm.askYesNoDialog($msg("obsidianLiveSyncSettingTab.msgAreYouSureProceed"), {
-                        defaultOption: "No",
-                    })) != "yes"
-                )
-                    return;
+        if (result.result === "scheduled") {
+            this.closeSetting();
+            return;
+        }
+        if (result.result === "failed") {
+            return;
+        }
+
+        const applyWithoutInitialisation = $msg(
+            "Ui.SetupWizard.ApplySettingsInitialisation.ApplyWithoutInitialisation"
+        );
+        const fallback = await this.core.confirm.confirmWithMessage(
+            $msg("Ui.SetupWizard.ApplySettingsInitialisation.BypassTitle"),
+            $msg("Ui.SetupWizard.ApplySettingsInitialisation.BypassGuidance"),
+            [applyWithoutInitialisation, keepEditing],
+            keepEditing
+        );
+        if (fallback === applyWithoutInitialisation) {
+            if (!this.editingSettings.encrypt) {
+                this.editingSettings.passphrase = "";
             }
-        }
-        if (!this.editingSettings.encrypt) {
-            this.editingSettings.passphrase = "";
-        }
-        await this.saveAllDirtySettings();
-        await Promise.resolve(this.applyAllSettings());
-        if (result == OPTION_FETCH) {
-            await this.core.storageAccess.writeFileAuto(FlagFilesHumanReadable.FETCH_ALL, "");
-            this.services.appLifecycle.scheduleRestart();
-            this.closeSetting();
-            // await rebuildDB("localOnly");
-        } else if (result == OPTION_REBUILD_BOTH) {
-            await this.core.storageAccess.writeFileAuto(FlagFilesHumanReadable.REBUILD_ALL, "");
-            this.services.appLifecycle.scheduleRestart();
-            this.closeSetting();
-        } else if (result == OPTION_ONLY_SETTING) {
-            await this.services.setting.saveSettingData();
+            await this.saveAllDirtySettings();
         }
     }
 

src/modules/features/SettingDialogue/ObsidianLiveSyncSettingTab.unit.spec.ts

@@ -1,9 +1,12 @@
-import { describe, expect, it, vi } from "vitest";
+import { beforeEach, describe, expect, it, vi } from "vitest";
 import { DEFAULT_SETTINGS, REMOTE_COUCHDB } from "@vrtmrz/livesync-commonlib/compat/common/types";
 
 const negotiationMocks = vi.hoisted(() => ({
     checkSyncInfo: vi.fn(async () => true),
 }));
+const settingsInitialisationMocks = vi.hoisted(() => ({
+    applySettingsWithInitialisationChoice: vi.fn(),
+}));
 
 vi.mock("@/deps.ts", () => ({
     App: class {},
@@ -63,6 +66,10 @@ vi.mock("./PaneMaintenance.ts", () => ({ paneMaintenance: vi.fn() }));
 import { LiveSyncCouchDBReplicator } from "@vrtmrz/livesync-commonlib/compat/replication/couchdb/LiveSyncReplicator";
 import { ObsidianLiveSyncSettingTab } from "./ObsidianLiveSyncSettingTab";
 
+beforeEach(() => {
+    settingsInitialisationMocks.applySettingsWithInitialisationChoice.mockReset();
+});
+
 describe("ObsidianLiveSyncSettingTab passphrase verification", () => {
     it("closes the finite remote connection after checking synchronisation information", async () => {
         const remoteDatabase = {
@@ -95,6 +102,116 @@ describe("ObsidianLiveSyncSettingTab passphrase verification", () => {
     });
 });
 
+describe("ObsidianLiveSyncSettingTab pending-setting initialisation", () => {
+    function createSettingsTab() {
+        const saveSettingData = vi.fn(async () => undefined);
+        const confirmWithMessage = vi.fn();
+        const plugin = {
+            app: {},
+            core: {
+                settings: {
+                    ...DEFAULT_SETTINGS,
+                    handleFilenameCaseSensitive: false,
+                },
+                getModule: vi.fn(() => settingsInitialisationMocks),
+                confirm: {
+                    confirmWithMessage,
+                },
+                services: {
+                    setting: {
+                        saveSettingData,
+                        getDeviceAndVaultName: vi.fn(() => ""),
+                    },
+                },
+            },
+        };
+        const tab = new ObsidianLiveSyncSettingTab({} as never, plugin as never);
+        Object.assign(tab, {
+            _editingSettings: {
+                ...DEFAULT_SETTINGS,
+                handleFilenameCaseSensitive: true,
+            },
+            initialSettings: {
+                ...DEFAULT_SETTINGS,
+                handleFilenameCaseSensitive: false,
+            },
+        });
+        vi.spyOn(tab, "isPassphraseValid").mockResolvedValue(true);
+        vi.spyOn(tab, "checkWorkingPassphrase").mockResolvedValue(true);
+        const closeSetting = vi.spyOn(tab, "closeSetting").mockImplementation(() => undefined);
+        return { tab, saveSettingData, confirmWithMessage, closeSetting };
+    }
+
+    it("keeps pending settings in the editing buffer when initialisation and the fallback are cancelled", async () => {
+        const { tab, saveSettingData, confirmWithMessage, closeSetting } = createSettingsTab();
+        settingsInitialisationMocks.applySettingsWithInitialisationChoice.mockResolvedValueOnce({
+            result: "cancelled",
+        });
+        confirmWithMessage.mockResolvedValueOnce("Keep Editing");
+
+        await tab.confirmRebuild();
+
+        expect(settingsInitialisationMocks.applySettingsWithInitialisationChoice).toHaveBeenCalledOnce();
+        expect(confirmWithMessage).toHaveBeenCalledWith(
+            "Apply Settings without Initialisation?",
+            expect.any(String),
+            ["Apply without Initialisation", "Keep Editing"],
+            "Keep Editing"
+        );
+        expect(saveSettingData).not.toHaveBeenCalled();
+        expect(tab.editingSettings.handleFilenameCaseSensitive).toBe(true);
+        expect(tab.core.settings.handleFilenameCaseSensitive).toBe(false);
+        expect(closeSetting).not.toHaveBeenCalled();
+    });
+
+    it("applies pending settings only after a separately confirmed initialisation bypass", async () => {
+        const { tab, saveSettingData, confirmWithMessage, closeSetting } = createSettingsTab();
+        settingsInitialisationMocks.applySettingsWithInitialisationChoice.mockResolvedValueOnce({
+            result: "cancelled",
+        });
+        confirmWithMessage.mockResolvedValueOnce("Apply without Initialisation");
+
+        await tab.confirmRebuild();
+
+        expect(settingsInitialisationMocks.applySettingsWithInitialisationChoice).toHaveBeenCalledOnce();
+        expect(saveSettingData).toHaveBeenCalledOnce();
+        expect(tab.core.settings.handleFilenameCaseSensitive).toBe(true);
+        expect(closeSetting).not.toHaveBeenCalled();
+    });
+
+    it("closes settings only after initialisation has been scheduled", async () => {
+        const { tab, saveSettingData, confirmWithMessage, closeSetting } = createSettingsTab();
+        settingsInitialisationMocks.applySettingsWithInitialisationChoice.mockImplementationOnce(
+            async ({ applySettings }: { applySettings: () => Promise<void> }) => {
+                await applySettings();
+                return { result: "scheduled", mode: "rebuild" };
+            }
+        );
+
+        await tab.confirmRebuild();
+
+        expect(saveSettingData).toHaveBeenCalledOnce();
+        expect(confirmWithMessage).not.toHaveBeenCalled();
+        expect(closeSetting).toHaveBeenCalledOnce();
+    });
+
+    it("does not offer the settings-only fallback after an initialisation failure", async () => {
+        const { tab, saveSettingData, confirmWithMessage, closeSetting } = createSettingsTab();
+        settingsInitialisationMocks.applySettingsWithInitialisationChoice.mockResolvedValueOnce({
+            result: "failed",
+            mode: "fetch",
+        });
+
+        await tab.confirmRebuild();
+
+        expect(saveSettingData).not.toHaveBeenCalled();
+        expect(confirmWithMessage).not.toHaveBeenCalled();
+        expect(tab.editingSettings.handleFilenameCaseSensitive).toBe(true);
+        expect(tab.core.settings.handleFilenameCaseSensitive).toBe(false);
+        expect(closeSetting).not.toHaveBeenCalled();
+    });
+});
+
 describe("ObsidianLiveSyncSettingTab declarative settings boundary", () => {
     function createSettingsTab() {
         const saveSettingData = vi.fn(async () => undefined);

src/modules/features/SetupManager.ts

@@ -19,6 +19,7 @@ import UseSetupURI from "./SetupWizard/dialogs/UseSetupURI.svelte";
 import OutroNewUser from "./SetupWizard/dialogs/OutroNewUser.svelte";
 import OutroExistingUser from "./SetupWizard/dialogs/OutroExistingUser.svelte";
 import OutroAskUserMode from "./SetupWizard/dialogs/OutroAskUserMode.svelte";
+import ApplySettingsInitialisation from "./SetupWizard/dialogs/ApplySettingsInitialisation.svelte";
 import SetupRemote from "./SetupWizard/dialogs/SetupRemote.svelte";
 import SetupRemoteCouchDB from "./SetupWizard/dialogs/SetupRemoteCouchDB.svelte";
 import SetupRemoteBucket from "./SetupWizard/dialogs/SetupRemoteBucket.svelte";
@@ -38,10 +39,13 @@ import type {
     SetupRemoteP2PResultType,
     SetupRemoteResultType,
     UseSetupURIResultType,
+    ApplySettingsInitialisationResultType,
+    ApplySettingsInitialisationInitialData,
 } from "./SetupWizard/dialogs/setupDialogTypes.ts";
 import {
     applySettingsAndFetchOnActivation,
     applySettingsWithScheduledInitialisation,
+    type SetupInitialisationMode,
 } from "@/serviceFeatures/setupObsidian/setupActivationLifecycle.ts";
 import { isP2PMainRemote } from "@/common/remoteConfiguration.ts";
 
@@ -75,6 +79,17 @@ export const enum UserMode {
     Update = "unknown", // Alias for Unknown for better readability
 }
 
+export type SettingsInitialisationApplicationResult =
+    | { result: "scheduled"; mode: SetupInitialisationMode }
+    | { result: "cancelled" }
+    | { result: "failed"; mode: SetupInitialisationMode };
+
+export type ApplySettingsWithInitialisationChoiceOptions = {
+    applySettings: () => Promise<void>;
+    isP2P: boolean;
+    validateChoice?: (mode: SetupInitialisationMode) => Promise<boolean>;
+};
+
 /**
  * Setup Manager to handle onboarding and configuration setup
  */
@@ -87,6 +102,32 @@ export class SetupManager extends AbstractModule {
         return this.services.UI.dialogManager;
     }
 
+    /**
+     * Ask which existing data should be authoritative for pending setting changes,
+     * then reserve the matching next-start operation before applying them.
+     *
+     * Cancellation and reservation failure remain distinct so the caller may
+     * offer an explicit settings-only fallback only after a user cancellation.
+     */
+    async applySettingsWithInitialisationChoice({
+        applySettings,
+        isP2P,
+        validateChoice = () => Promise.resolve(true),
+    }: ApplySettingsWithInitialisationChoiceOptions): Promise<SettingsInitialisationApplicationResult> {
+        const mode = await this.dialogManager.openWithExplicitCancel<
+            ApplySettingsInitialisationResultType,
+            ApplySettingsInitialisationInitialData
+        >(ApplySettingsInitialisation, { isP2P });
+        if (mode === "cancelled") {
+            return { result: "cancelled" };
+        }
+        if (!(await validateChoice(mode))) {
+            return { result: "failed", mode };
+        }
+        const scheduled = await applySettingsWithScheduledInitialisation(this.core.rebuilder, mode, applySettings);
+        return scheduled ? { result: "scheduled", mode } : { result: "failed", mode };
+    }
+
     /**
      * Starts the onboarding process
      * @returns Promise that resolves to true if onboarding completed successfully, false otherwise

src/modules/features/SetupManager.unit.spec.ts

@@ -17,6 +17,7 @@ vi.mock("./SetupWizard/dialogs/UseSetupURI.svelte", () => ({ default: {} }));
 vi.mock("./SetupWizard/dialogs/OutroNewUser.svelte", () => ({ default: {} }));
 vi.mock("./SetupWizard/dialogs/OutroExistingUser.svelte", () => ({ default: {} }));
 vi.mock("./SetupWizard/dialogs/OutroAskUserMode.svelte", () => ({ default: {} }));
+vi.mock("./SetupWizard/dialogs/ApplySettingsInitialisation.svelte", () => ({ default: {} }));
 vi.mock("./SetupWizard/dialogs/SetupRemote.svelte", () => ({ default: {} }));
 vi.mock("./SetupWizard/dialogs/SetupRemoteCouchDB.svelte", () => ({ default: {} }));
 vi.mock("./SetupWizard/dialogs/SetupRemoteBucket.svelte", () => ({ default: {} }));
@@ -273,6 +274,64 @@ describe("SetupManager", () => {
         expect(setting.currentSettings().isConfigured).toBe(false);
     });
 
+    it("reports cancellation separately when applying settings which require initialisation", async () => {
+        const { manager, dialogManager, core } = createSetupManager();
+        const applySettings = vi.fn(async () => undefined);
+        dialogManager.openWithExplicitCancel.mockResolvedValueOnce("cancelled");
+
+        const result = await manager.applySettingsWithInitialisationChoice({ applySettings, isP2P: true });
+
+        expect(result).toEqual({ result: "cancelled" });
+        expect(dialogManager.openWithExplicitCancel).toHaveBeenCalledWith(expect.anything(), { isP2P: true });
+        expect(core.rebuilder.scheduleFetch).not.toHaveBeenCalled();
+        expect(core.rebuilder.scheduleRebuild).not.toHaveBeenCalled();
+        expect(applySettings).not.toHaveBeenCalled();
+    });
+
+    it("reserves the selected initialisation before applying pending settings", async () => {
+        const { manager, dialogManager, core } = createSetupManager();
+        const applySettings = vi.fn(async () => undefined);
+        dialogManager.openWithExplicitCancel.mockResolvedValueOnce("fetch");
+
+        const result = await manager.applySettingsWithInitialisationChoice({ applySettings, isP2P: false });
+
+        expect(result).toEqual({ result: "scheduled", mode: "fetch" });
+        expect(core.rebuilder.scheduleFetch).toHaveBeenCalledWith(expect.any(Function));
+        expect(core.rebuilder.scheduleFetch.mock.invocationCallOrder[0]).toBeLessThan(
+            applySettings.mock.invocationCallOrder[0]
+        );
+    });
+
+    it("reports a failed reservation without applying pending settings", async () => {
+        const { manager, dialogManager, core } = createSetupManager();
+        const applySettings = vi.fn(async () => undefined);
+        core.rebuilder.scheduleRebuild.mockResolvedValueOnce(false);
+        dialogManager.openWithExplicitCancel.mockResolvedValueOnce("rebuild");
+
+        const result = await manager.applySettingsWithInitialisationChoice({ applySettings, isP2P: false });
+
+        expect(result).toEqual({ result: "failed", mode: "rebuild" });
+        expect(applySettings).not.toHaveBeenCalled();
+    });
+
+    it("does not reserve initialisation when the selected source cannot be validated", async () => {
+        const { manager, dialogManager, core } = createSetupManager();
+        const applySettings = vi.fn(async () => undefined);
+        const validateChoice = vi.fn(async () => false);
+        dialogManager.openWithExplicitCancel.mockResolvedValueOnce("fetch");
+
+        const result = await manager.applySettingsWithInitialisationChoice({
+            applySettings,
+            isP2P: false,
+            validateChoice,
+        });
+
+        expect(result).toEqual({ result: "failed", mode: "fetch" });
+        expect(validateChoice).toHaveBeenCalledWith("fetch");
+        expect(core.rebuilder.scheduleFetch).not.toHaveBeenCalled();
+        expect(applySettings).not.toHaveBeenCalled();
+    });
+
     it("preserves modern profiles, display names, and the active selection from a Setup URI", async () => {
         const { manager, setting, dialogManager } = createSetupManager();
         const imported = {

src/modules/features/SetupWizard/dialogs/ApplySettingsInitialisation.svelte

@@ -0,0 +1,85 @@
+<script lang="ts">
+    import DialogHeader from "@/modules/services/LiveSyncUI/components/DialogHeader.svelte";
+    import Guidance from "@/modules/services/LiveSyncUI/components/Guidance.svelte";
+    import Decision from "@/modules/services/LiveSyncUI/components/Decision.svelte";
+    import Question from "@/modules/services/LiveSyncUI/components/Question.svelte";
+    import Option from "@/modules/services/LiveSyncUI/components/Option.svelte";
+    import Instruction from "@/modules/services/LiveSyncUI/components/Instruction.svelte";
+    import UserDecisions from "@/modules/services/LiveSyncUI/components/UserDecisions.svelte";
+    import InfoNote from "@/modules/services/LiveSyncUI/components/InfoNote.svelte";
+    import { $msg as msg } from "@/common/translation";
+    import {
+        type ApplySettingsInitialisationInitialData,
+        type ApplySettingsInitialisationResultType,
+        TYPE_CANCELLED,
+        TYPE_FETCH,
+        TYPE_REBUILD,
+    } from "./setupDialogTypes";
+
+    type Props = {
+        setResult: (result: ApplySettingsInitialisationResultType) => void;
+        getInitialData?: () => ApplySettingsInitialisationInitialData | undefined;
+    };
+    const { setResult, getInitialData }: Props = $props();
+    const isP2P = $derived(getInitialData?.()?.isP2P === true);
+    let selectedMode = $state<ApplySettingsInitialisationResultType>(TYPE_CANCELLED);
+    const canProceed = $derived(selectedMode === TYPE_FETCH || selectedMode === TYPE_REBUILD);
+    const proceedMessage = $derived.by(() => {
+        if (selectedMode === TYPE_FETCH) {
+            return isP2P
+                ? msg("Ui.SetupWizard.ApplySettingsInitialisation.ProceedFetchP2P")
+                : msg("Ui.SetupWizard.ApplySettingsInitialisation.ProceedFetch");
+        }
+        if (selectedMode === TYPE_REBUILD) {
+            return isP2P
+                ? msg("Ui.SetupWizard.ApplySettingsInitialisation.ProceedRebuildP2P")
+                : msg("Ui.SetupWizard.ApplySettingsInitialisation.ProceedRebuild");
+        }
+        return msg("Ui.SetupWizard.Common.ProceedSelectOption");
+    });
+</script>
+
+<DialogHeader title={msg("Ui.SetupWizard.ApplySettingsInitialisation.Title")} />
+<Guidance>
+    <p>{msg("Ui.SetupWizard.ApplySettingsInitialisation.Guidance")}</p>
+</Guidance>
+<Instruction>
+    <Question>{msg("Ui.SetupWizard.ApplySettingsInitialisation.Question")}</Question>
+    <Option
+        title={msg("Ui.SetupWizard.ApplySettingsInitialisation.FetchOption")}
+        bind:value={selectedMode}
+        selectedValue={TYPE_FETCH}
+    >
+        <InfoNote notice>
+            {isP2P
+                ? msg("Ui.SetupWizard.ApplySettingsInitialisation.FetchOptionP2PDesc")
+                : msg("Ui.SetupWizard.ApplySettingsInitialisation.FetchOptionDesc")}
+        </InfoNote>
+    </Option>
+    <Option
+        title={isP2P
+            ? msg("Ui.SetupWizard.ApplySettingsInitialisation.RebuildOptionP2P")
+            : msg("Ui.SetupWizard.ApplySettingsInitialisation.RebuildOption")}
+        bind:value={selectedMode}
+        selectedValue={TYPE_REBUILD}
+    >
+        <InfoNote warning={!isP2P} notice={isP2P}>
+            {isP2P
+                ? msg("Ui.SetupWizard.ApplySettingsInitialisation.RebuildOptionP2PDesc")
+                : msg("Ui.SetupWizard.ApplySettingsInitialisation.RebuildOptionDesc")}
+        </InfoNote>
+    </Option>
+</Instruction>
+<UserDecisions>
+    <Decision
+        title={proceedMessage}
+        important={selectedMode !== TYPE_REBUILD || isP2P}
+        destructive={selectedMode === TYPE_REBUILD && !isP2P}
+        disabled={!canProceed}
+        commit={() => setResult(selectedMode)}
+    />
+    <Decision
+        title={msg("Ui.SetupWizard.ApplySettingsInitialisation.Back")}
+        commit={() => setResult(TYPE_CANCELLED)}
+    />
+</UserDecisions>

src/modules/features/SetupWizard/dialogs/setupDialogTypes.ts

@@ -28,6 +28,10 @@ export const TYPE_COMPATIBLE_EXISTING = "compatible-existing-user";
 // OutroExistingUser
 export const TYPE_APPLY = "apply";
 
+// Applying pending settings which require database initialisation
+export const TYPE_FETCH = "fetch";
+export const TYPE_REBUILD = "rebuild";
+
 // Select methods
 export const TYPE_USE_SETUP_URI = "use-setup-uri";
 export const TYPE_SCAN_QR_CODE = "scan-qr-code";
@@ -82,6 +86,12 @@ export type OutroExistingUserResultType = typeof TYPE_APPLY | typeof TYPE_CANCEL
 
 export type OutroNewUserResultType = typeof TYPE_APPLY | typeof TYPE_CANCELLED;
 
+export type ApplySettingsInitialisationResultType = typeof TYPE_FETCH | typeof TYPE_REBUILD | typeof TYPE_CANCELLED;
+
+export type ApplySettingsInitialisationInitialData = {
+    isP2P: boolean;
+};
+
 export type SelectMethodNewUserResultType =
     | typeof TYPE_USE_SETUP_URI
     | typeof TYPE_CONFIGURE_MANUALLY