import type { DesktopSettings } from '@/lib/desktop';
import { sanitizeWorkStatusHiddenSections } from '@/components/chat/work-status/sections';
import { createProjectIdFromPath } from '@/lib/projectId';
import { useUIStore } from '@/stores/useUIStore';
import { isMonoFontOption, isUiFontOption } from '@/lib/fontOptions';
import {
  DEFAULT_FOLLOW_UP_BEHAVIOR,
  isFollowUpBehavior,
  normalizeFollowUpBehavior,
  useMessageQueueStore,
  type FollowUpBehavior,
} from '@/stores/messageQueueStore';
import { setDirectoryShowHidden } from '@/lib/directoryShowHidden';
import { setFilesViewShowGitignored } from '@/lib/filesViewShowGitignored';
import { loadAppearancePreferences, applyAppearancePreferences } from '@/lib/appearancePersistence';
import { getRegisteredRuntimeAPIs } from '@/contexts/runtimeAPIRegistry';
import { sanitizeStarterRefs } from '@/lib/draftStarters';
import { normalizeMobileKeyboardMode, setStoredMobileKeyboardMode } from '@/lib/mobileKeyboardMode';
import { runtimeFetch } from '@/lib/runtime-fetch';
import { isTerminalShell } from '@/lib/terminalShell';
import { getRuntimeKey, subscribeRuntimeEndpointChanged, subscribeRuntimeEndpointWillChange } from '@/lib/runtime-switch';
import { DEFAULT_DARK_THEME_ID, DEFAULT_LIGHT_THEME_ID } from '@/lib/theme/themes';
import { DEFAULT_OPEN_IN_APP_ID } from '@/lib/openInApps';
import { useSessionDisplayStore } from '@/stores/useSessionDisplayStore';

export const applyPersistedHomeDirectoryToWindow = (homeDirectory: string): void => {
  if (typeof window === 'undefined') {
    return;
  }
  if (typeof window.__OPENCHAMBER_HOME__ === 'string' && window.__OPENCHAMBER_HOME__.length > 0) {
    return;
  }

  try {
    window.__OPENCHAMBER_HOME__ = homeDirectory;
  } catch {
    /* read-only contextBridge property — leave preload-seeded value */
  }
};

const SETTINGS_MIRROR_INDEX_KEY = 'openchamber.settingsMirror.v2.index';
const SETTINGS_MIRROR_KEY_PREFIX = 'openchamber.settingsMirror.v2:';
const MAX_SETTINGS_MIRROR_RUNTIMES = 5;

export const getRuntimeSettingsMirrorStorageKey = (runtimeKey: string): string =>
  `${SETTINGS_MIRROR_KEY_PREFIX}${encodeURIComponent(runtimeKey)}`;

const setOrRemoveLocalStorage = (key: string, value: string | null): void => {
  if (value === null) {
    localStorage.removeItem(key);
  } else {
    localStorage.setItem(key, value);
  }
};

const persistRuntimeSettingsMirror = (settings: DesktopSettings, runtimeKey: string): void => {
  const mirror = {
    themeId: settings.themeId,
    themeVariant: settings.themeVariant,
    lightThemeId: settings.lightThemeId,
    darkThemeId: settings.darkThemeId,
    useSystemTheme: settings.useSystemTheme,
    lastDirectory: settings.lastDirectory,
    homeDirectory: settings.homeDirectory,
    projects: settings.projects,
    activeProjectId: settings.activeProjectId,
    sidebarProjectDisplayMode: settings.sidebarProjectDisplayMode,
    sidebarSessionGroupingMode: settings.sidebarSessionGroupingMode,
    sidebarProjectSortOrder: settings.sidebarProjectSortOrder,
    sidebarShowRecentSection: settings.sidebarShowRecentSection,
    pinnedDirectories: settings.pinnedDirectories,
    gitmojiEnabled: settings.gitmojiEnabled,
    directoryShowHidden: settings.directoryShowHidden,
    filesViewShowGitignored: settings.filesViewShowGitignored,
    openInAppId: settings.openInAppId,
    pwaAppName: settings.pwaAppName,
    mobileKeyboardMode: settings.mobileKeyboardMode,
    openCodeUpdateToastDismissedVersion: settings.openCodeUpdateToastDismissedVersion,
    dictationEnabled: settings.dictationEnabled,
    sttProvider: settings.sttProvider,
    sttServerUrl: settings.sttServerUrl,
    sttModel: settings.sttModel,
    sttLocalModel: settings.sttLocalModel,
    sttLanguage: settings.sttLanguage,
  };
  localStorage.setItem(getRuntimeSettingsMirrorStorageKey(runtimeKey), JSON.stringify(mirror));

  let previous: string[] = [];
  try {
    const parsed = JSON.parse(localStorage.getItem(SETTINGS_MIRROR_INDEX_KEY) ?? '[]') as unknown;
    if (Array.isArray(parsed)) previous = parsed.filter((entry): entry is string => typeof entry === 'string');
  } catch {
    previous = [];
  }
  const runtimes = [runtimeKey, ...previous.filter((entry) => entry !== runtimeKey)].slice(0, MAX_SETTINGS_MIRROR_RUNTIMES);
  for (const staleRuntime of previous) {
    if (!runtimes.includes(staleRuntime)) localStorage.removeItem(getRuntimeSettingsMirrorStorageKey(staleRuntime));
  }
  localStorage.setItem(SETTINGS_MIRROR_INDEX_KEY, JSON.stringify(runtimes));
};

const persistToLocalStorage = (settings: DesktopSettings) => {
  if (typeof window === 'undefined') {
    return;
  }

  persistRuntimeSettingsMirror(settings, getRuntimeKey());
  setOrRemoveLocalStorage('selectedThemeId', settings.themeId || null);
  setOrRemoveLocalStorage('selectedThemeVariant', settings.themeVariant || null);
  setOrRemoveLocalStorage('lightThemeId', settings.lightThemeId || null);
  setOrRemoveLocalStorage('darkThemeId', settings.darkThemeId || null);
  setOrRemoveLocalStorage('useSystemTheme', typeof settings.useSystemTheme === 'boolean' ? String(settings.useSystemTheme) : null);
  setOrRemoveLocalStorage('lastDirectory', settings.lastDirectory || null);
  if (settings.homeDirectory) {
    localStorage.setItem('homeDirectory', settings.homeDirectory);
    applyPersistedHomeDirectoryToWindow(settings.homeDirectory);
  } else {
    localStorage.removeItem('homeDirectory');
  }
  if (Array.isArray(settings.projects) && settings.projects.length > 0) {
    localStorage.setItem('projects', JSON.stringify(settings.projects));
  } else {
    localStorage.removeItem('projects');
  }
  if (settings.activeProjectId) {
    localStorage.setItem('activeProjectId', settings.activeProjectId);
  } else {
    localStorage.removeItem('activeProjectId');
  }
  if (Array.isArray(settings.pinnedDirectories) && settings.pinnedDirectories.length > 0) {
    localStorage.setItem('pinnedDirectories', JSON.stringify(settings.pinnedDirectories));
  } else {
    localStorage.removeItem('pinnedDirectories');
  }

  if (Array.isArray(settings.projects) && settings.projects.length > 0) {
    const collapsed = settings.projects
      .filter((project) => project.sidebarCollapsed === true)
      .map((project) => project.id)
      .filter((id): id is string => typeof id === 'string' && id.length > 0);
    if (collapsed.length > 0) {
      localStorage.setItem('oc.sessions.projectCollapse', JSON.stringify(collapsed));
    } else {
      localStorage.removeItem('oc.sessions.projectCollapse');
    }
  } else {
    localStorage.removeItem('oc.sessions.projectCollapse');
  }
  if (typeof settings.gitmojiEnabled === 'boolean') {
    localStorage.setItem('gitmojiEnabled', String(settings.gitmojiEnabled));
  } else {
    localStorage.removeItem('gitmojiEnabled');
  }
  if (typeof settings.directoryShowHidden === 'boolean') {
    localStorage.setItem('directoryTreeShowHidden', settings.directoryShowHidden ? 'true' : 'false');
  } else {
    localStorage.removeItem('directoryTreeShowHidden');
  }
  if (typeof settings.filesViewShowGitignored === 'boolean') {
    localStorage.setItem('filesViewShowGitignored', settings.filesViewShowGitignored ? 'true' : 'false');
  } else {
    localStorage.removeItem('filesViewShowGitignored');
  }
  setOrRemoveLocalStorage('openInAppId', typeof settings.openInAppId === 'string' && settings.openInAppId.length > 0 ? settings.openInAppId : null);
  if (typeof settings.pwaAppName === 'string') {
    const normalized = settings.pwaAppName.trim().replace(/\s+/g, ' ').slice(0, 64);
    if (normalized.length > 0) {
      localStorage.setItem('openchamber.pwaName', normalized);
    } else {
      localStorage.removeItem('openchamber.pwaName');
    }
  } else {
    localStorage.removeItem('openchamber.pwaName');
  }
  setStoredMobileKeyboardMode(settings.mobileKeyboardMode);
  if (typeof settings.openCodeUpdateToastDismissedVersion === 'string') {
    const version = settings.openCodeUpdateToastDismissedVersion.trim();
    if (version) {
      localStorage.setItem('opencode-update-toast-dismissed-version', version);
    } else {
      localStorage.removeItem('opencode-update-toast-dismissed-version');
    }
  } else {
    localStorage.removeItem('opencode-update-toast-dismissed-version');
  }
  if (typeof settings.dictationEnabled === 'boolean') {
    localStorage.setItem('dictationEnabled', String(settings.dictationEnabled));
  } else {
    localStorage.removeItem('dictationEnabled');
  }
  if (settings.sttProvider === 'local' || settings.sttProvider === 'openai-compatible') {
    localStorage.setItem('sttProvider', settings.sttProvider);
  } else {
    localStorage.removeItem('sttProvider');
  }
  setOrRemoveLocalStorage('sttServerUrl', typeof settings.sttServerUrl === 'string' ? settings.sttServerUrl : null);
  setOrRemoveLocalStorage('sttModel', typeof settings.sttModel === 'string' ? settings.sttModel : null);
  setOrRemoveLocalStorage('sttLocalModel', typeof settings.sttLocalModel === 'string' ? settings.sttLocalModel : null);
  setOrRemoveLocalStorage('sttLanguage', typeof settings.sttLanguage === 'string' ? settings.sttLanguage : null);
};

const dispatchSettingsSynced = (settings: DesktopSettings): void => {
  if (typeof window === 'undefined') {
    return;
  }
  window.dispatchEvent(new CustomEvent<DesktopSettings>('openchamber:settings-synced', { detail: settings }));
};

type SettingsSaveState = 'idle' | 'saving' | 'error';

let _settingsSaveState: SettingsSaveState = 'idle';
let _settingsSaveStateResetTimer: ReturnType<typeof setTimeout> | null = null;
const _settingsSaveStateListeners = new Set<() => void>();

export const getSettingsSaveState = (): SettingsSaveState => _settingsSaveState;

export const subscribeToSettingsSaveState = (listener: () => void): (() => void) => {
  _settingsSaveStateListeners.add(listener);
  return () => _settingsSaveStateListeners.delete(listener);
};

/**
 * Drive the shared settings save indicator from pages that persist through
 * their own APIs instead of updateDesktopSettings. 'error' resets to idle.
 */
export const reportSettingsSaveState = (state: 'saving' | 'saved' | 'error'): void => {
  dispatchSettingsSaveState(state);
};

const dispatchSettingsSaveState = (state: 'saving' | 'saved' | 'error'): void => {
  if (_settingsSaveStateResetTimer) {
    clearTimeout(_settingsSaveStateResetTimer);
    _settingsSaveStateResetTimer = null;
  }

  // Quiet indicator: success is the normal case and renders nothing ('saved' → idle);
  // only in-flight saves and failures surface in the UI.
  const nextState: SettingsSaveState = state === 'saved' ? 'idle' : state;
  if (nextState !== _settingsSaveState) {
    _settingsSaveState = nextState;
    _settingsSaveStateListeners.forEach((listener) => listener());
  }

  if (nextState === 'error') {
    _settingsSaveStateResetTimer = setTimeout(() => dispatchSettingsSaveState('saved'), 6000);
  }

  if (typeof window === 'undefined') {
    return;
  }
  window.dispatchEvent(new CustomEvent<'saving' | 'saved' | 'error'>('openchamber:settings-save-state', { detail: state }));
};

type PersistApi = {
  hasHydrated?: () => boolean;
  onFinishHydration?: (callback: () => void) => (() => void) | undefined;
};

const sanitizeSkillCatalogs = (value: unknown): DesktopSettings['skillCatalogs'] | undefined => {
  if (!Array.isArray(value)) {
    return undefined;
  }

  const result: NonNullable<DesktopSettings['skillCatalogs']> = [];
  const seen = new Set<string>();

  for (const entry of value) {
    if (!entry || typeof entry !== 'object') continue;
    const candidate = entry as Record<string, unknown>;

    const id = typeof candidate.id === 'string' ? candidate.id.trim() : '';
    const label = typeof candidate.label === 'string' ? candidate.label.trim() : '';
    const source = typeof candidate.source === 'string' ? candidate.source.trim() : '';
    const subpath = typeof candidate.subpath === 'string' ? candidate.subpath.trim() : '';
    const gitIdentityId = typeof candidate.gitIdentityId === 'string' ? candidate.gitIdentityId.trim() : '';

    if (!id || !label || !source) continue;
    if (seen.has(id)) continue;
    seen.add(id);

    const catalog: NonNullable<DesktopSettings['skillCatalogs']>[number] = {
      id,
      label,
      source,
    };
    if (subpath) catalog.subpath = subpath;
    if (gitIdentityId) catalog.gitIdentityId = gitIdentityId;
    result.push(catalog);
  }

  return result;
};

const sanitizeShortcutOverrides = (value: unknown): Record<string, string> | undefined => {
  if (!value || typeof value !== 'object' || Array.isArray(value)) {
    return undefined;
  }
  const result: Record<string, string> = {};
  for (const [key, combo] of Object.entries(value)) {
    const normalizedKey = typeof key === 'string' ? key.trim() : '';
    const normalizedCombo = typeof combo === 'string' ? combo.trim() : '';
    if (!normalizedKey || !normalizedCombo) continue;
    result[normalizedKey] = normalizedCombo;
  }
  return result;
};

const areStringRecordsEqual = (left: Record<string, string>, right: Record<string, string>): boolean => {
  const leftEntries = Object.entries(left);
  const rightEntries = Object.entries(right);
  if (leftEntries.length !== rightEntries.length) return false;
  return leftEntries.every(([key, value]) => right[key] === value);
};

const areModelRefsEqual = (
  left: Array<{ providerID: string; modelID: string }>,
  right: Array<{ providerID: string; modelID: string }>,
): boolean => (
  left.length === right.length &&
  left.every((item, idx) => item.providerID === right[idx]?.providerID && item.modelID === right[idx]?.modelID)
);

const areStringArraysEqual = (left: string[], right: string[]): boolean => (
  left.length === right.length && left.every((value, idx) => value === right[idx])
);

const sanitizeStringArray = (value: unknown): string[] | undefined => {
  if (!Array.isArray(value)) return undefined;
  return Array.from(new Set(value.filter((entry): entry is string => typeof entry === 'string' && entry.length > 0)));
};

const sanitizeRecentEfforts = (value: unknown): Record<string, string[]> | undefined => {
  if (!value || typeof value !== 'object' || Array.isArray(value)) return undefined;
  const result: Record<string, string[]> = {};
  for (const [key, variants] of Object.entries(value)) {
    if (!key || !Array.isArray(variants)) continue;
    const sanitized = sanitizeStringArray(variants);
    if (sanitized && sanitized.length > 0) {
      result[key] = sanitized.slice(0, 5);
    }
  }
  return Object.keys(result).length > 0 ? result : undefined;
};

const areRecentEffortsEqual = (left: Record<string, string[]>, right: Record<string, string[]>): boolean => {
  const leftKeys = Object.keys(left);
  if (leftKeys.length !== Object.keys(right).length) return false;
  return leftKeys.every((key) => Array.isArray(right[key]) && areStringArraysEqual(left[key], right[key]));
};

const HEX_COLOR_PATTERN = /^#(?:[\da-fA-F]{3}|[\da-fA-F]{6})$/;

const normalizeIconBackground = (value: unknown): string | null => {
  if (typeof value !== 'string') {
    return null;
  }
  const trimmed = value.trim();
  if (!trimmed) {
    return null;
  }
  return HEX_COLOR_PATTERN.test(trimmed) ? trimmed.toLowerCase() : null;
};

const sanitizeProjects = (value: unknown): DesktopSettings['projects'] | undefined => {
  if (!Array.isArray(value)) {
    return undefined;
  }

  const result: NonNullable<DesktopSettings['projects']> = [];
  const seenIds = new Set<string>();
  const seenPaths = new Set<string>();

  for (const entry of value) {
    if (!entry || typeof entry !== 'object') continue;
    const candidate = entry as Record<string, unknown>;

    const rawPath = typeof candidate.path === 'string' ? candidate.path.trim() : '';
    if (!rawPath) continue;

    const normalizedPath = rawPath === '/' ? rawPath : rawPath.replace(/\\/g, '/').replace(/\/+$/, '');
    if (!normalizedPath) continue;

    const id = createProjectIdFromPath(normalizedPath);
    if (!id) continue;

    if (seenIds.has(id) || seenPaths.has(normalizedPath)) continue;
    seenIds.add(id);
    seenPaths.add(normalizedPath);

    const project: NonNullable<DesktopSettings['projects']>[number] = {
      id,
      path: normalizedPath,
    };

    if (typeof candidate.label === 'string' && candidate.label.trim().length > 0) {
      project.label = candidate.label.trim();
    }
    if (typeof candidate.icon === 'string' && candidate.icon.trim().length > 0) {
      project.icon = candidate.icon.trim();
    }
    if (candidate.iconImage === null) {
      project.iconImage = null;
    } else if (candidate.iconImage && typeof candidate.iconImage === 'object') {
      const iconImage = candidate.iconImage as Record<string, unknown>;
      const mime = typeof iconImage.mime === 'string' ? iconImage.mime.trim() : '';
      const updatedAt = typeof iconImage.updatedAt === 'number' && Number.isFinite(iconImage.updatedAt)
        ? Math.max(0, Math.round(iconImage.updatedAt))
        : 0;
      const source = iconImage.source === 'custom' || iconImage.source === 'auto'
        ? iconImage.source
        : null;
      if (mime && updatedAt > 0 && source) {
        project.iconImage = { mime, updatedAt, source };
      }
    }
    if (typeof candidate.color === 'string' && candidate.color.trim().length > 0) {
      project.color = candidate.color.trim();
    }
    if (candidate.iconBackground === null) {
      project.iconBackground = null;
    } else {
      const iconBackground = normalizeIconBackground(candidate.iconBackground);
      if (iconBackground) {
        project.iconBackground = iconBackground;
      }
    }
    if (typeof candidate.addedAt === 'number' && Number.isFinite(candidate.addedAt) && candidate.addedAt >= 0) {
      project.addedAt = candidate.addedAt;
    }
    if (
      typeof candidate.lastOpenedAt === 'number' &&
      Number.isFinite(candidate.lastOpenedAt) &&
      candidate.lastOpenedAt >= 0
    ) {
      project.lastOpenedAt = candidate.lastOpenedAt;
    }
    if (typeof candidate.sidebarCollapsed === 'boolean') {
      project.sidebarCollapsed = candidate.sidebarCollapsed;
    }
    result.push(project);
  }

  return result.length > 0 ? result : undefined;
};

const sanitizeManagedRemoteTunnelPresets = (value: unknown): DesktopSettings['managedRemoteTunnelPresets'] | undefined => {
  if (!Array.isArray(value)) {
    return undefined;
  }

  const result: NonNullable<DesktopSettings['managedRemoteTunnelPresets']> = [];
  const seenIds = new Set<string>();
  const seenHostnames = new Set<string>();

  for (const entry of value) {
    if (!entry || typeof entry !== 'object') continue;
    const candidate = entry as Record<string, unknown>;

    const id = typeof candidate.id === 'string' ? candidate.id.trim() : '';
    const name = typeof candidate.name === 'string' ? candidate.name.trim() : '';
    const hostname = typeof candidate.hostname === 'string' ? candidate.hostname.trim().toLowerCase() : '';

    if (!id || !name || !hostname) continue;
    if (seenIds.has(id) || seenHostnames.has(hostname)) continue;
    seenIds.add(id);
    seenHostnames.add(hostname);

    result.push({ id, name, hostname });
  }

  return result;
};

const sanitizeManagedRemoteTunnelPresetTokens = (value: unknown): DesktopSettings['managedRemoteTunnelPresetTokens'] | undefined => {
  if (!value || typeof value !== 'object' || Array.isArray(value)) {
    return undefined;
  }

  const candidate = value as Record<string, unknown>;
  const result: Record<string, string> = {};
  for (const [key, tokenValue] of Object.entries(candidate)) {
    const id = key.trim();
    const token = typeof tokenValue === 'string' ? tokenValue.trim() : '';
    if (!id || !token) continue;
    result[id] = token;
  }

  return Object.keys(result).length > 0 ? result : undefined;
};

const sanitizeModelRefs = (value: unknown, limit: number): Array<{ providerID: string; modelID: string }> | undefined => {
  if (!Array.isArray(value)) {
    return undefined;
  }

  const result: Array<{ providerID: string; modelID: string }> = [];
  const seen = new Set<string>();

  for (const entry of value) {
    if (!entry || typeof entry !== 'object') continue;
    const candidate = entry as Record<string, unknown>;
    const providerID = typeof candidate.providerID === 'string' ? candidate.providerID.trim() : '';
    const modelID = typeof candidate.modelID === 'string' ? candidate.modelID.trim() : '';
    if (!providerID || !modelID) continue;
    const key = `${providerID}/${modelID}`;
    if (seen.has(key)) continue;
    seen.add(key);
    result.push({ providerID, modelID });
    if (result.length >= limit) break;
  }

  return result;
};

const getPersistApi = (): PersistApi | undefined => {
  const candidate = useUIStore.persist;
  if (candidate && typeof candidate === 'object') {
    return candidate;
  }
  return undefined;
};

const getRuntimeSettingsAPI = () => getRegisteredRuntimeAPIs()?.settings ?? null;

const materializeAuthoritativeUiSettings = (settings: DesktopSettings): DesktopSettings => {
  const defaults = useUIStore.getInitialState();

  return {
    useSystemTheme: true,
    lightThemeId: DEFAULT_LIGHT_THEME_ID,
    darkThemeId: DEFAULT_DARK_THEME_ID,
    openInAppId: DEFAULT_OPEN_IN_APP_ID,
    showReasoningTraces: defaults.showReasoningTraces,
    streamingAutoFollowEnabled: defaults.streamingAutoFollowEnabled,
    workStatusPanelEnabled: defaults.workStatusPanelEnabled,
    workStatusHiddenSections: defaults.workStatusHiddenSections,
    sessionRecapEnabled: defaults.sessionRecapEnabled,
    sessionSuggestionEnabled: defaults.sessionSuggestionEnabled,
    sessionGoalEnabled: defaults.sessionGoalEnabled,
    sessionGoalDefaultBudgetEnabled: defaults.sessionGoalDefaultBudgetEnabled,
    sessionGoalDefaultBudget: defaults.sessionGoalDefaultBudget,
    collapsibleThinkingBlocks: defaults.collapsibleThinkingBlocks,
    autoDeleteEnabled: defaults.autoDeleteEnabled,
    autoSaveEnabled: defaults.autoSaveEnabled,
    autoDeleteAfterDays: defaults.autoDeleteAfterDays,
    sessionRetentionAction: defaults.sessionRetentionAction,
    followUpBehavior: DEFAULT_FOLLOW_UP_BEHAVIOR,
    showDeletionDialog: defaults.showDeletionDialog,
    nativeNotificationsEnabled: defaults.nativeNotificationsEnabled,
    notificationMode: defaults.notificationMode,
    notifyOnSubtasks: defaults.notifyOnSubtasks,
    notifyOnCompletion: defaults.notifyOnCompletion,
    notifyOnError: defaults.notifyOnError,
    notifyOnQuestion: defaults.notifyOnQuestion,
    notificationTemplates: defaults.notificationTemplates,
    summarizeLastMessage: defaults.summarizeLastMessage,
    summaryThreshold: defaults.summaryThreshold,
    summaryLength: defaults.summaryLength,
    maxLastMessageLength: defaults.maxLastMessageLength,
    inputSpellcheckEnabled: defaults.inputSpellcheckEnabled,
    showOpenCodeUpdateNotifications: defaults.showOpenCodeUpdateNotifications,
    agentControlToolEnabled: defaults.agentControlToolEnabled,
    agentWebToolEnabled: defaults.agentWebToolEnabled,
    agentMemoryToolEnabled: defaults.agentMemoryToolEnabled,
    showToolFileIcons: defaults.showToolFileIcons,
    codeBlockLineWrap: defaults.codeBlockLineWrap,
    showTurnChangedFiles: defaults.showTurnChangedFiles,
    showExpandedBashTools: defaults.showExpandedBashTools,
    showExpandedEditTools: defaults.showExpandedEditTools,
    timeFormatPreference: defaults.timeFormatPreference,
    weekStartPreference: defaults.weekStartPreference,
    desktopWindowControlsPosition: defaults.desktopWindowControlsPosition,
    desktopWindowControlsStyle: defaults.desktopWindowControlsStyle,
    chatRenderMode: defaults.chatRenderMode,
    activityRenderMode: defaults.activityRenderMode,
    mermaidRenderingMode: defaults.mermaidRenderingMode,
    userMessageRenderingMode: defaults.userMessageRenderingMode,
    collapsibleUserMessages: defaults.collapsibleUserMessages,
    messageStreamTransport: 'auto',
    stickyUserHeader: defaults.stickyUserHeader,
    promptNavigatorEnabled: defaults.promptNavigatorEnabled,
    wideChatLayoutEnabled: defaults.wideChatLayoutEnabled,
    showSplitAssistantMessageActions: defaults.showSplitAssistantMessageActions,
    draftStartersVisible: defaults.draftStartersVisible,
    reportUsage: defaults.reportUsage,
    fontSize: defaults.fontSize,
    terminalFontSize: defaults.terminalFontSize,
    terminalShell: defaults.terminalShell,
    terminalLoginShells: defaults.terminalLoginShells,
    editorFontSize: defaults.editorFontSize,
    uiFont: defaults.uiFont,
    monoFont: defaults.monoFont,
    padding: defaults.padding,
    cornerRadius: defaults.cornerRadius,
    inputBarOffset: defaults.inputBarOffset,
    shortcutOverrides: defaults.shortcutOverrides,
    mobileKeyboardMode: 'resize-content',
    favoriteModels: defaults.favoriteModels,
    hiddenModels: defaults.hiddenModels,
    collapsedModelProviders: defaults.collapsedModelProviders,
    recentModels: defaults.recentModels,
    recentAgents: defaults.recentAgents,
    recentEfforts: defaults.recentEfforts,
    diffLayoutPreference: defaults.diffLayoutPreference,
    gitChangesViewMode: defaults.gitChangesViewMode,
    directoryShowHidden: true,
    filesViewShowGitignored: false,
    dictationEnabled: true,
    sttProvider: 'local',
    sttServerUrl: 'http://localhost:8001/v1',
    sttModel: 'deepdml/faster-whisper-large-v3-turbo-ct2',
    sttLocalModel: 'parakeet-tdt-0.6b-v2-int8',
    sttLanguage: '',
    ...settings,
  };
};

const applyDesktopUiPreferences = (settings: DesktopSettings) => {
  const store = useUIStore.getState();
  const configStore = typeof window !== 'undefined'
    ? window.__zustand_config_store__?.getState?.() ?? null
    : null;
  const configStoreApi = typeof window !== 'undefined'
    ? window.__zustand_config_store__ ?? null
    : null;
  const queueStore = useMessageQueueStore.getState();

  if (typeof settings.workStatusPanelEnabled === 'boolean'
    && settings.workStatusPanelEnabled !== store.workStatusPanelEnabled) {
    store.setWorkStatusPanelEnabled(settings.workStatusPanelEnabled);
  }
  if (Array.isArray(settings.workStatusHiddenSections)) {
    const next = sanitizeWorkStatusHiddenSections(settings.workStatusHiddenSections);
    if (next.join('\u0000') !== store.workStatusHiddenSections.join('\u0000')) {
      store.setWorkStatusHiddenSections(next);
    }
  }
  if (typeof settings.showReasoningTraces === 'boolean' && settings.showReasoningTraces !== store.showReasoningTraces) {
    store.setShowReasoningTraces(settings.showReasoningTraces);
  }
  if (typeof settings.streamingAutoFollowEnabled === 'boolean' && settings.streamingAutoFollowEnabled !== store.streamingAutoFollowEnabled) {
    store.setStreamingAutoFollowEnabled(settings.streamingAutoFollowEnabled);
  }
  if (typeof settings.sessionRecapEnabled === 'boolean' && settings.sessionRecapEnabled !== store.sessionRecapEnabled) {
    store.setSessionRecapEnabled(settings.sessionRecapEnabled);
  }
  if (typeof settings.sessionSuggestionEnabled === 'boolean' && settings.sessionSuggestionEnabled !== store.sessionSuggestionEnabled) {
    store.setSessionSuggestionEnabled(settings.sessionSuggestionEnabled);
  }
  if (typeof settings.sessionGoalEnabled === 'boolean' && settings.sessionGoalEnabled !== store.sessionGoalEnabled) {
    store.setSessionGoalEnabled(settings.sessionGoalEnabled);
  }
  if (typeof settings.sessionGoalDefaultBudgetEnabled === 'boolean' && settings.sessionGoalDefaultBudgetEnabled !== store.sessionGoalDefaultBudgetEnabled) {
    store.setSessionGoalDefaultBudgetEnabled(settings.sessionGoalDefaultBudgetEnabled);
  }
  if (typeof settings.sessionGoalDefaultBudget === 'number' && Number.isFinite(settings.sessionGoalDefaultBudget) && settings.sessionGoalDefaultBudget !== store.sessionGoalDefaultBudget) {
    store.setSessionGoalDefaultBudget(settings.sessionGoalDefaultBudget);
  }
  if (typeof settings.collapsibleThinkingBlocks === 'boolean' && settings.collapsibleThinkingBlocks !== store.collapsibleThinkingBlocks) {
    store.setCollapsibleThinkingBlocks(settings.collapsibleThinkingBlocks);
  }
  if (typeof settings.autoDeleteEnabled === 'boolean' && settings.autoDeleteEnabled !== store.autoDeleteEnabled) {
    store.setAutoDeleteEnabled(settings.autoDeleteEnabled);
  }
  if (typeof settings.autoSaveEnabled === 'boolean' && settings.autoSaveEnabled !== store.autoSaveEnabled) {
    store.setAutoSaveEnabled(settings.autoSaveEnabled);
  }
  if (typeof settings.autoDeleteAfterDays === 'number' && Number.isFinite(settings.autoDeleteAfterDays)) {
    const normalized = Math.max(1, Math.min(365, settings.autoDeleteAfterDays));
    if (normalized !== store.autoDeleteAfterDays) {
      store.setAutoDeleteAfterDays(normalized);
    }
  }
  if (settings.sessionRetentionAction === 'archive' || settings.sessionRetentionAction === 'delete') {
    if (settings.sessionRetentionAction !== store.sessionRetentionAction) {
      store.setSessionRetentionAction(settings.sessionRetentionAction);
    }
  }

  let nextFollowUpBehavior: FollowUpBehavior | null = null;
  if (isFollowUpBehavior(settings.followUpBehavior)) {
    nextFollowUpBehavior = settings.followUpBehavior;
  } else if (typeof settings.queueModeEnabled === 'boolean') {
    nextFollowUpBehavior = normalizeFollowUpBehavior(undefined, settings.queueModeEnabled);
  }
  if (nextFollowUpBehavior && nextFollowUpBehavior !== queueStore.followUpBehavior) {
    queueStore.setFollowUpBehavior(nextFollowUpBehavior);
  }

  if (typeof settings.showDeletionDialog === 'boolean' && settings.showDeletionDialog !== store.showDeletionDialog) {
    store.setShowDeletionDialog(settings.showDeletionDialog);
  }
  if (typeof settings.nativeNotificationsEnabled === 'boolean' && settings.nativeNotificationsEnabled !== store.nativeNotificationsEnabled) {
    store.setNativeNotificationsEnabled(settings.nativeNotificationsEnabled);
  }
  if (typeof settings.notificationMode === 'string' && (settings.notificationMode === 'always' || settings.notificationMode === 'hidden-only')) {
    if (settings.notificationMode !== store.notificationMode) {
      store.setNotificationMode(settings.notificationMode);
    }
  }
  if (typeof settings.notifyOnSubtasks === 'boolean' && settings.notifyOnSubtasks !== store.notifyOnSubtasks) {
    store.setNotifyOnSubtasks(settings.notifyOnSubtasks);
  }
  if (typeof settings.notifyOnCompletion === 'boolean' && settings.notifyOnCompletion !== store.notifyOnCompletion) {
    store.setNotifyOnCompletion(settings.notifyOnCompletion);
  }
  if (typeof settings.notifyOnError === 'boolean' && settings.notifyOnError !== store.notifyOnError) {
    store.setNotifyOnError(settings.notifyOnError);
  }
  if (typeof settings.notifyOnQuestion === 'boolean' && settings.notifyOnQuestion !== store.notifyOnQuestion) {
    store.setNotifyOnQuestion(settings.notifyOnQuestion);
  }
  if (settings.notificationTemplates && typeof settings.notificationTemplates === 'object') {
    store.setNotificationTemplates(settings.notificationTemplates);
  }
  if (typeof settings.summarizeLastMessage === 'boolean' && settings.summarizeLastMessage !== store.summarizeLastMessage) {
    store.setSummarizeLastMessage(settings.summarizeLastMessage);
  }
  if (typeof settings.summaryThreshold === 'number' && Number.isFinite(settings.summaryThreshold)) {
    store.setSummaryThreshold(settings.summaryThreshold);
  }
  if (typeof settings.summaryLength === 'number' && Number.isFinite(settings.summaryLength)) {
    store.setSummaryLength(settings.summaryLength);
  }
  if (typeof settings.maxLastMessageLength === 'number' && Number.isFinite(settings.maxLastMessageLength)) {
    store.setMaxLastMessageLength(settings.maxLastMessageLength);
  }
  if (typeof settings.inputSpellcheckEnabled === 'boolean' && settings.inputSpellcheckEnabled !== store.inputSpellcheckEnabled) {
    store.setInputSpellcheckEnabled(settings.inputSpellcheckEnabled);
  }
  if (
    typeof settings.showOpenCodeUpdateNotifications === 'boolean'
    && settings.showOpenCodeUpdateNotifications !== store.showOpenCodeUpdateNotifications
  ) {
    store.setShowOpenCodeUpdateNotifications(settings.showOpenCodeUpdateNotifications);
  }
  if (
    typeof settings.agentControlToolEnabled === 'boolean'
    && settings.agentControlToolEnabled !== store.agentControlToolEnabled
  ) {
    store.setAgentControlToolEnabled(settings.agentControlToolEnabled);
  }
  if (
    typeof settings.agentWebToolEnabled === 'boolean'
    && settings.agentWebToolEnabled !== store.agentWebToolEnabled
  ) {
    store.setAgentWebToolEnabled(settings.agentWebToolEnabled);
  }
  if (
    typeof settings.agentMemoryToolEnabled === 'boolean'
    && settings.agentMemoryToolEnabled !== store.agentMemoryToolEnabled
  ) {
    store.setAgentMemoryToolEnabled(settings.agentMemoryToolEnabled);
  }
  // Server-owned: it says whether this build has the feature at all.
  if (
    typeof settings.agentMemoryFeatureAvailable === 'boolean'
    && settings.agentMemoryFeatureAvailable !== store.agentMemoryFeatureAvailable
  ) {
    store.setAgentMemoryFeatureAvailable(settings.agentMemoryFeatureAvailable);
  }
  if (typeof settings.showToolFileIcons === 'boolean' && settings.showToolFileIcons !== store.showToolFileIcons) {
    store.setShowToolFileIcons(settings.showToolFileIcons);
  }
  if (typeof settings.codeBlockLineWrap === 'boolean' && settings.codeBlockLineWrap !== store.codeBlockLineWrap) {
    store.setCodeBlockLineWrap(settings.codeBlockLineWrap);
  }
  if (typeof settings.showTurnChangedFiles === 'boolean' && settings.showTurnChangedFiles !== store.showTurnChangedFiles) {
    store.setShowTurnChangedFiles(settings.showTurnChangedFiles);
  }
  if (typeof settings.showExpandedBashTools === 'boolean' && settings.showExpandedBashTools !== store.showExpandedBashTools) {
    store.setShowExpandedBashTools(settings.showExpandedBashTools);
  }
  if (typeof settings.showExpandedEditTools === 'boolean' && settings.showExpandedEditTools !== store.showExpandedEditTools) {
    store.setShowExpandedEditTools(settings.showExpandedEditTools);
  }
  if (typeof settings.timeFormatPreference === 'string'
    && (settings.timeFormatPreference === 'auto' || settings.timeFormatPreference === '12h' || settings.timeFormatPreference === '24h')) {
    if (settings.timeFormatPreference !== store.timeFormatPreference) {
      store.setTimeFormatPreference(settings.timeFormatPreference);
    }
  }
  if (typeof settings.weekStartPreference === 'string'
    && (settings.weekStartPreference === 'auto' || settings.weekStartPreference === 'sunday' || settings.weekStartPreference === 'monday')) {
    if (settings.weekStartPreference !== store.weekStartPreference) {
      store.setWeekStartPreference(settings.weekStartPreference);
    }
  }
  if (typeof settings.desktopWindowControlsPosition === 'string') {
    const nextPosition = settings.desktopWindowControlsPosition === 'left'
      ? 'left'
      : (settings.desktopWindowControlsPosition === 'right' || settings.desktopWindowControlsPosition === 'auto')
        ? 'right'
        : null;
    if (nextPosition && nextPosition !== store.desktopWindowControlsPosition) {
      store.setDesktopWindowControlsPosition(nextPosition);
    }
  }
  if (typeof settings.desktopWindowControlsStyle === 'string') {
    const nextStyle = settings.desktopWindowControlsStyle === 'traffic-lights'
      ? 'traffic-lights'
      : settings.desktopWindowControlsStyle === 'classic'
        ? 'classic'
        : null;
    if (nextStyle && nextStyle !== store.desktopWindowControlsStyle) {
      store.setDesktopWindowControlsStyle(nextStyle);
    }
  }
  if (typeof settings.chatRenderMode === 'string'
    && (settings.chatRenderMode === 'sorted' || settings.chatRenderMode === 'live')) {
    if (settings.chatRenderMode !== store.chatRenderMode) {
      store.setChatRenderMode(settings.chatRenderMode);
    }
  }
  if (typeof settings.activityRenderMode === 'string'
    && (settings.activityRenderMode === 'collapsed' || settings.activityRenderMode === 'summary')) {
    if (settings.activityRenderMode !== store.activityRenderMode) {
      store.setActivityRenderMode(settings.activityRenderMode);
    }
  }
  if (typeof settings.mermaidRenderingMode === 'string'
    && (settings.mermaidRenderingMode === 'svg' || settings.mermaidRenderingMode === 'ascii')) {
    if (settings.mermaidRenderingMode !== store.mermaidRenderingMode) {
      store.setMermaidRenderingMode(settings.mermaidRenderingMode);
    }
  }
  if (typeof settings.userMessageRenderingMode === 'string'
    && (settings.userMessageRenderingMode === 'markdown' || settings.userMessageRenderingMode === 'plain')) {
    if (settings.userMessageRenderingMode !== store.userMessageRenderingMode) {
      store.setUserMessageRenderingMode(settings.userMessageRenderingMode);
    }
  }
  if (typeof settings.collapsibleUserMessages === 'boolean' && settings.collapsibleUserMessages !== store.collapsibleUserMessages) {
    store.setCollapsibleUserMessages(settings.collapsibleUserMessages);
  }
  if (typeof settings.messageStreamTransport === 'string'
    && (settings.messageStreamTransport === 'auto' || settings.messageStreamTransport === 'ws' || settings.messageStreamTransport === 'sse')) {
    if (configStore && settings.messageStreamTransport !== configStore.settingsMessageStreamTransport) {
      configStore.setSettingsMessageStreamTransport(settings.messageStreamTransport);
    }
  }
  if (typeof settings.stickyUserHeader === 'boolean' && settings.stickyUserHeader !== store.stickyUserHeader) {
    store.setStickyUserHeader(settings.stickyUserHeader);
  }
  if (typeof settings.promptNavigatorEnabled === 'boolean' && settings.promptNavigatorEnabled !== store.promptNavigatorEnabled) {
    store.setPromptNavigatorEnabled(settings.promptNavigatorEnabled);
  }
  if (typeof settings.wideChatLayoutEnabled === 'boolean' && settings.wideChatLayoutEnabled !== store.wideChatLayoutEnabled) {
    store.setWideChatLayoutEnabled(settings.wideChatLayoutEnabled);
  }
  if (
    typeof settings.showSplitAssistantMessageActions === 'boolean'
    && settings.showSplitAssistantMessageActions !== store.showSplitAssistantMessageActions
  ) {
    store.setShowSplitAssistantMessageActions(settings.showSplitAssistantMessageActions);
  }
  if (typeof settings.reportUsage === 'boolean' && settings.reportUsage !== store.reportUsage) {
    store.setReportUsage(settings.reportUsage);
  }
  if (typeof settings.fontSize === 'number' && Number.isFinite(settings.fontSize) && settings.fontSize !== store.fontSize) {
    store.setFontSize(settings.fontSize);
  }
  if (Array.isArray(settings.draftStarters)) {
    let nextStarters = sanitizeStarterRefs(settings.draftStarters);
    if (settings.draftStartersCraftGoalAdded !== true && !nextStarters.some((starter) => starter.type === 'command' && starter.name === 'craft-goal')) {
      const planIndex = nextStarters.findIndex((starter) => starter.type === 'command' && starter.name === 'plan-feature');
      const insertAt = planIndex >= 0 ? planIndex + 1 : nextStarters.length;
      nextStarters = [
        ...nextStarters.slice(0, insertAt),
        { type: 'command', name: 'craft-goal' },
        ...nextStarters.slice(insertAt),
      ];
    }
    if (settings.draftStartersScheduleTaskAdded !== true && !nextStarters.some((starter) => starter.type === 'command' && starter.name === 'schedule-task')) {
      const goalIndex = nextStarters.findIndex((starter) => starter.type === 'command' && starter.name === 'craft-goal');
      const insertAt = goalIndex >= 0 ? goalIndex + 1 : nextStarters.length;
      nextStarters = [
        ...nextStarters.slice(0, insertAt),
        { type: 'command', name: 'schedule-task' },
        ...nextStarters.slice(insertAt),
      ];
    }
    if (JSON.stringify(store.globalDraftStarters) !== JSON.stringify(nextStarters)) {
      store.setGlobalDraftStarters(nextStarters);
    }
    if (settings.draftStartersCraftGoalAdded !== true || settings.draftStartersScheduleTaskAdded !== true) {
      settings.draftStarters = nextStarters;
      settings.draftStartersCraftGoalAdded = true;
      settings.draftStartersScheduleTaskAdded = true;
    }
  } else {
    // The built-in default already contains Craft a Goal and Schedule a Task;
    // only persist the markers so removing them later remains a durable user
    // choice.
    if (settings.draftStartersCraftGoalAdded !== true) {
      settings.draftStartersCraftGoalAdded = true;
    }
    if (settings.draftStartersScheduleTaskAdded !== true) {
      settings.draftStartersScheduleTaskAdded = true;
    }
  }
  if (typeof settings.draftStartersVisible === 'boolean' && settings.draftStartersVisible !== store.draftStartersVisible) {
    store.setDraftStartersVisible(settings.draftStartersVisible);
  }
  if (typeof settings.terminalFontSize === 'number' && Number.isFinite(settings.terminalFontSize) && settings.terminalFontSize !== store.terminalFontSize) {
    store.setTerminalFontSize(settings.terminalFontSize);
  }
  if (isTerminalShell(settings.terminalShell) && settings.terminalShell !== store.terminalShell) {
    store.setTerminalShell(settings.terminalShell);
  }
  if (
    Array.isArray(settings.terminalLoginShells)
    && (
      settings.terminalLoginShells.length !== store.terminalLoginShells.length
      || settings.terminalLoginShells.some((shell, index) => shell !== store.terminalLoginShells[index])
    )
  ) {
    store.setTerminalLoginShells(settings.terminalLoginShells);
  }
  if (typeof settings.editorFontSize === 'number' && Number.isFinite(settings.editorFontSize) && settings.editorFontSize !== store.editorFontSize) {
    store.setEditorFontSize(settings.editorFontSize);
  }
  if (isUiFontOption(settings.uiFont) && settings.uiFont !== store.uiFont) {
    store.setUiFont(settings.uiFont);
  }
  if (isMonoFontOption(settings.monoFont) && settings.monoFont !== store.monoFont) {
    store.setMonoFont(settings.monoFont);
  }
  if (typeof settings.padding === 'number' && Number.isFinite(settings.padding) && settings.padding !== store.padding) {
    store.setPadding(settings.padding);
  }
  if (typeof settings.cornerRadius === 'number' && Number.isFinite(settings.cornerRadius) && settings.cornerRadius !== store.cornerRadius) {
    store.setCornerRadius(settings.cornerRadius);
  }
  if (typeof settings.inputBarOffset === 'number' && Number.isFinite(settings.inputBarOffset) && settings.inputBarOffset !== store.inputBarOffset) {
    store.setInputBarOffset(settings.inputBarOffset);
  }
  if (settings.shortcutOverrides && !areStringRecordsEqual(settings.shortcutOverrides, store.shortcutOverrides)) {
    useUIStore.setState({ shortcutOverrides: settings.shortcutOverrides });
  }
  if (typeof settings.mobileKeyboardMode === 'string') {
    const mode = normalizeMobileKeyboardMode(settings.mobileKeyboardMode, store.mobileKeyboardMode);
    if (mode !== store.mobileKeyboardMode) {
      store.setMobileKeyboardMode(mode);
    }
  }
  if (configStoreApi && configStore) {
    const nextConfigState: Partial<typeof configStore> = {};
    if (typeof settings.dictationEnabled === 'boolean' && settings.dictationEnabled !== configStore.dictationEnabled) {
      nextConfigState.dictationEnabled = settings.dictationEnabled;
    }
    if ((settings.sttProvider === 'local' || settings.sttProvider === 'openai-compatible') && settings.sttProvider !== configStore.sttProvider) {
      nextConfigState.sttProvider = settings.sttProvider;
    }
    if (typeof settings.sttServerUrl === 'string' && settings.sttServerUrl !== configStore.sttServerUrl) {
      nextConfigState.sttServerUrl = settings.sttServerUrl;
    }
    if (typeof settings.sttModel === 'string' && settings.sttModel !== configStore.sttModel) {
      nextConfigState.sttModel = settings.sttModel;
    }
    if (typeof settings.sttLocalModel === 'string' && settings.sttLocalModel !== configStore.sttLocalModel) {
      nextConfigState.sttLocalModel = settings.sttLocalModel;
    }
    if (typeof settings.sttLanguage === 'string' && settings.sttLanguage !== configStore.sttLanguage) {
      nextConfigState.sttLanguage = settings.sttLanguage;
    }
    if (Object.keys(nextConfigState).length > 0) {
      configStoreApi.setState(nextConfigState);
    }
  }

  if (Array.isArray(settings.favoriteModels)) {
    const current = store.favoriteModels;
    const next = settings.favoriteModels;
    if (!areModelRefsEqual(current, next)) {
      useUIStore.setState({ favoriteModels: next });
    }
  }

  if (Array.isArray(settings.hiddenModels)) {
    const current = store.hiddenModels;
    const next = settings.hiddenModels;
    if (!areModelRefsEqual(current, next)) {
      useUIStore.setState({ hiddenModels: next });
    }
  }

  if (Array.isArray(settings.collapsedModelProviders)) {
    const current = store.collapsedModelProviders;
    const next = settings.collapsedModelProviders;
    if (!areStringArraysEqual(current, next)) {
      useUIStore.setState({ collapsedModelProviders: next });
    }
  }

  if (Array.isArray(settings.recentModels)) {
    const current = store.recentModels;
    const next = settings.recentModels;
    if (!areModelRefsEqual(current, next)) {
      useUIStore.setState({ recentModels: next });
    }
  }

  if (Array.isArray(settings.recentAgents)) {
    const current = store.recentAgents;
    const next = settings.recentAgents;
    if (!areStringArraysEqual(current, next)) {
      useUIStore.setState({ recentAgents: next });
    }
  }

  if (settings.recentEfforts && typeof settings.recentEfforts === 'object') {
    const current = store.recentEfforts;
    const next = settings.recentEfforts;
    if (!areRecentEffortsEqual(current, next)) {
      useUIStore.setState({ recentEfforts: next });
    }
  }
  if (typeof settings.diffLayoutPreference === 'string'
    && (settings.diffLayoutPreference === 'dynamic' || settings.diffLayoutPreference === 'inline' || settings.diffLayoutPreference === 'side-by-side')) {
    if (settings.diffLayoutPreference !== store.diffLayoutPreference) {
      store.setDiffLayoutPreference(settings.diffLayoutPreference);
    }
  }
  if (typeof settings.gitChangesViewMode === 'string'
    && (settings.gitChangesViewMode === 'flat' || settings.gitChangesViewMode === 'tree')) {
    if (settings.gitChangesViewMode !== store.gitChangesViewMode) {
      store.setGitChangesViewMode(settings.gitChangesViewMode);
    }
  }
  if (typeof settings.directoryShowHidden === 'boolean') {
    setDirectoryShowHidden(settings.directoryShowHidden, { persist: false });
  }
  if (typeof settings.filesViewShowGitignored === 'boolean') {
    setFilesViewShowGitignored(settings.filesViewShowGitignored, { persist: false });
  }
  const sessionDisplayChanges: Partial<ReturnType<typeof useSessionDisplayStore.getState>> = {};
  if (settings.sidebarProjectDisplayMode === 'all' || settings.sidebarProjectDisplayMode === 'single') {
    sessionDisplayChanges.projectDisplayMode = settings.sidebarProjectDisplayMode;
  }
  if (settings.sidebarSessionGroupingMode === 'by-worktree' || settings.sidebarSessionGroupingMode === 'flat') {
    sessionDisplayChanges.sessionGroupingMode = settings.sidebarSessionGroupingMode;
  }
  if (settings.sidebarProjectSortOrder === 'manual'
    || settings.sidebarProjectSortOrder === 'a-z'
    || settings.sidebarProjectSortOrder === 'z-a'
    || settings.sidebarProjectSortOrder === 'date-added'
    || settings.sidebarProjectSortOrder === 'recent') {
    sessionDisplayChanges.projectSortOrder = settings.sidebarProjectSortOrder;
  }
  if (typeof settings.sidebarShowRecentSection === 'boolean') {
    sessionDisplayChanges.showRecentSection = settings.sidebarShowRecentSection;
  }
  if (Object.keys(sessionDisplayChanges).length > 0) {
    useSessionDisplayStore.setState(sessionDisplayChanges);
  }
};

const sanitizeWebSettings = (payload: unknown): DesktopSettings | null => {
  if (!payload || typeof payload !== 'object') {
    return null;
  }

  const candidate = payload as Record<string, unknown>;
  const result: DesktopSettings = {};

  if (typeof candidate.themeId === 'string' && candidate.themeId.length > 0) {
    result.themeId = candidate.themeId;
  }
  if (candidate.useSystemTheme === true || candidate.useSystemTheme === false) {
    result.useSystemTheme = candidate.useSystemTheme;
  }
  if (typeof candidate.themeVariant === 'string' && (candidate.themeVariant === 'light' || candidate.themeVariant === 'dark')) {
    result.themeVariant = candidate.themeVariant;
  }
  if (typeof candidate.lightThemeId === 'string' && candidate.lightThemeId.length > 0) {
    result.lightThemeId = candidate.lightThemeId;
  }
  if (typeof candidate.darkThemeId === 'string' && candidate.darkThemeId.length > 0) {
    result.darkThemeId = candidate.darkThemeId;
  }
  if (typeof candidate.lastDirectory === 'string' && candidate.lastDirectory.length > 0) {
    result.lastDirectory = candidate.lastDirectory;
  }
  if (typeof candidate.homeDirectory === 'string' && candidate.homeDirectory.length > 0) {
    result.homeDirectory = candidate.homeDirectory;
  }

  if (typeof candidate.opencodeBinary === 'string') {
    const trimmed = candidate.opencodeBinary.trim();
    result.opencodeBinary = trimmed.length > 0 ? trimmed : undefined;
  }
  if (typeof candidate.desktopLanAccessEnabled === 'boolean') {
    result.desktopLanAccessEnabled = candidate.desktopLanAccessEnabled;
  }
  if (typeof candidate.desktopKeepAwakeEnabled === 'boolean') {
    result.desktopKeepAwakeEnabled = candidate.desktopKeepAwakeEnabled;
  }
  if (typeof candidate.desktopMinimizeToTrayEnabled === 'boolean') {
    result.desktopMinimizeToTrayEnabled = candidate.desktopMinimizeToTrayEnabled;
  }
  if (typeof candidate.desktopMacMenuBarEnabled === 'boolean') {
    result.desktopMacMenuBarEnabled = candidate.desktopMacMenuBarEnabled;
  }

  const projects = sanitizeProjects(candidate.projects);
  if (projects) {
    result.projects = projects;
  }
  if (typeof candidate.activeProjectId === 'string' && candidate.activeProjectId.length > 0) {
    result.activeProjectId = candidate.activeProjectId;
  }
  if (candidate.sidebarProjectDisplayMode === 'all' || candidate.sidebarProjectDisplayMode === 'single') {
    result.sidebarProjectDisplayMode = candidate.sidebarProjectDisplayMode;
  }
  if (candidate.sidebarSessionGroupingMode === 'by-worktree' || candidate.sidebarSessionGroupingMode === 'flat') {
    result.sidebarSessionGroupingMode = candidate.sidebarSessionGroupingMode;
  }
  if (candidate.sidebarProjectSortOrder === 'manual'
    || candidate.sidebarProjectSortOrder === 'a-z'
    || candidate.sidebarProjectSortOrder === 'z-a'
    || candidate.sidebarProjectSortOrder === 'date-added'
    || candidate.sidebarProjectSortOrder === 'recent') {
    result.sidebarProjectSortOrder = candidate.sidebarProjectSortOrder;
  }
  if (typeof candidate.sidebarShowRecentSection === 'boolean') {
    result.sidebarShowRecentSection = candidate.sidebarShowRecentSection;
  }

  if (Array.isArray(candidate.securityScopedBookmarks)) {
    result.securityScopedBookmarks = candidate.securityScopedBookmarks.filter(
      (entry): entry is string => typeof entry === 'string' && entry.length > 0
    );
  }
  if (Array.isArray(candidate.pinnedDirectories)) {
    result.pinnedDirectories = Array.from(
      new Set(
        candidate.pinnedDirectories.filter((entry): entry is string => typeof entry === 'string' && entry.length > 0)
      )
    );
  }
  if (Array.isArray(candidate.draftStarters)) {
    result.draftStarters = sanitizeStarterRefs(candidate.draftStarters);
  }
  if (typeof candidate.draftStartersVisible === 'boolean') {
    result.draftStartersVisible = candidate.draftStartersVisible;
  }
  if (typeof candidate.draftStartersCraftGoalAdded === 'boolean') {
    result.draftStartersCraftGoalAdded = candidate.draftStartersCraftGoalAdded;
  }
  if (typeof candidate.draftStartersScheduleTaskAdded === 'boolean') {
    result.draftStartersScheduleTaskAdded = candidate.draftStartersScheduleTaskAdded;
  }
  if (typeof candidate.workStatusPanelEnabled === 'boolean') {
    result.workStatusPanelEnabled = candidate.workStatusPanelEnabled;
  }
  if (Array.isArray(candidate.workStatusHiddenSections)) {
    // Unknown ids are dropped rather than kept: they would hide nothing and
    // accumulate forever as sections get renamed.
    result.workStatusHiddenSections = sanitizeWorkStatusHiddenSections(candidate.workStatusHiddenSections);
  }
  if (typeof candidate.showReasoningTraces === 'boolean') {
    result.showReasoningTraces = candidate.showReasoningTraces;
  }
  if (typeof candidate.streamingAutoFollowEnabled === 'boolean') {
    result.streamingAutoFollowEnabled = candidate.streamingAutoFollowEnabled;
  }
  if (typeof candidate.sessionRecapEnabled === 'boolean') {
    result.sessionRecapEnabled = candidate.sessionRecapEnabled;
  }
  if (typeof candidate.sessionSuggestionEnabled === 'boolean') {
    result.sessionSuggestionEnabled = candidate.sessionSuggestionEnabled;
  }
  if (typeof candidate.sessionGoalEnabled === 'boolean') {
    result.sessionGoalEnabled = candidate.sessionGoalEnabled;
  }
  if (typeof candidate.sessionGoalDefaultBudgetEnabled === 'boolean') {
    result.sessionGoalDefaultBudgetEnabled = candidate.sessionGoalDefaultBudgetEnabled;
  }
  if (typeof candidate.sessionGoalDefaultBudget === 'number' && Number.isFinite(candidate.sessionGoalDefaultBudget) && candidate.sessionGoalDefaultBudget > 0) {
    result.sessionGoalDefaultBudget = Math.floor(candidate.sessionGoalDefaultBudget);
  }
  if (typeof candidate.collapsibleThinkingBlocks === 'boolean') {
    result.collapsibleThinkingBlocks = candidate.collapsibleThinkingBlocks;
  }
  if (typeof candidate.autoDeleteEnabled === 'boolean') {
    result.autoDeleteEnabled = candidate.autoDeleteEnabled;
  }
  if (typeof candidate.autoSaveEnabled === 'boolean') {
    result.autoSaveEnabled = candidate.autoSaveEnabled;
  }
  if (typeof candidate.autoDeleteAfterDays === 'number' && Number.isFinite(candidate.autoDeleteAfterDays)) {
    result.autoDeleteAfterDays = candidate.autoDeleteAfterDays;
  }
  if (candidate.sessionRetentionAction === 'archive' || candidate.sessionRetentionAction === 'delete') {
    result.sessionRetentionAction = candidate.sessionRetentionAction;
  }
  if (typeof candidate.tunnelProvider === 'string') {
    const provider = candidate.tunnelProvider.trim().toLowerCase();
    if (provider.length > 0) {
      result.tunnelProvider = provider;
    }
  }
  if (typeof candidate.tunnelMode === 'string') {
    const mode = candidate.tunnelMode.trim().toLowerCase();
    if (mode === 'quick' || mode === 'managed-remote' || mode === 'managed-local') {
      result.tunnelMode = mode;
    }
  }
  if (candidate.tunnelBootstrapTtlMs === null) {
    result.tunnelBootstrapTtlMs = null;
  } else if (typeof candidate.tunnelBootstrapTtlMs === 'number' && Number.isFinite(candidate.tunnelBootstrapTtlMs)) {
    result.tunnelBootstrapTtlMs = candidate.tunnelBootstrapTtlMs;
  }
  if (typeof candidate.tunnelSessionTtlMs === 'number' && Number.isFinite(candidate.tunnelSessionTtlMs)) {
    result.tunnelSessionTtlMs = candidate.tunnelSessionTtlMs;
  }
  if (candidate.managedLocalTunnelConfigPath === null) {
    result.managedLocalTunnelConfigPath = null;
  } else if (typeof candidate.managedLocalTunnelConfigPath === 'string') {
    const trimmed = candidate.managedLocalTunnelConfigPath.trim();
    result.managedLocalTunnelConfigPath = trimmed.length > 0 ? trimmed : null;
  }
  if (typeof candidate.managedRemoteTunnelHostname === 'string') {
    result.managedRemoteTunnelHostname = candidate.managedRemoteTunnelHostname.trim();
  }
  if (candidate.managedRemoteTunnelToken === null) {
    result.managedRemoteTunnelToken = null;
  } else if (typeof candidate.managedRemoteTunnelToken === 'string') {
    result.managedRemoteTunnelToken = candidate.managedRemoteTunnelToken.trim();
  }
  const managedRemoteTunnelPresets = sanitizeManagedRemoteTunnelPresets(candidate.managedRemoteTunnelPresets);
  if (managedRemoteTunnelPresets) {
    result.managedRemoteTunnelPresets = managedRemoteTunnelPresets;
  }
  if (typeof candidate.managedRemoteTunnelSelectedPresetId === 'string') {
    const trimmed = candidate.managedRemoteTunnelSelectedPresetId.trim();
    result.managedRemoteTunnelSelectedPresetId = trimmed.length > 0 ? trimmed : undefined;
  }
  const managedRemoteTunnelPresetTokens = sanitizeManagedRemoteTunnelPresetTokens(candidate.managedRemoteTunnelPresetTokens);
  if (managedRemoteTunnelPresetTokens) {
    result.managedRemoteTunnelPresetTokens = managedRemoteTunnelPresetTokens;
  }
  if (typeof candidate.defaultModel === 'string' && candidate.defaultModel.length > 0) {
    result.defaultModel = candidate.defaultModel;
  }
  if (typeof candidate.defaultVariant === 'string' && candidate.defaultVariant.length > 0) {
    result.defaultVariant = candidate.defaultVariant;
  }
  if (typeof candidate.defaultAgent === 'string' && candidate.defaultAgent.length > 0) {
    result.defaultAgent = candidate.defaultAgent;
  }
  if (typeof candidate.smallModelUseDefault === 'boolean') {
    result.smallModelUseDefault = candidate.smallModelUseDefault;
  }
  if (typeof candidate.smallModelOverride === 'string' && candidate.smallModelOverride.length > 0) {
    result.smallModelOverride = candidate.smallModelOverride;
  }
  if (typeof candidate.walkthroughModelOverride === 'string' && candidate.walkthroughModelOverride.length > 0) {
    result.walkthroughModelOverride = candidate.walkthroughModelOverride;
  }
  if (typeof candidate.autoCreateWorktree === 'boolean') {
    result.autoCreateWorktree = candidate.autoCreateWorktree;
  }
  if (typeof candidate.gitmojiEnabled === 'boolean') {
    result.gitmojiEnabled = candidate.gitmojiEnabled;
  }
  if (isFollowUpBehavior(candidate.followUpBehavior)) {
    result.followUpBehavior = candidate.followUpBehavior;
  } else if (typeof candidate.queueModeEnabled === 'boolean') {
    result.followUpBehavior = normalizeFollowUpBehavior(undefined, candidate.queueModeEnabled);
  }
  if (typeof candidate.showDeletionDialog === 'boolean') {
    result.showDeletionDialog = candidate.showDeletionDialog;
  }
  if (typeof candidate.nativeNotificationsEnabled === 'boolean') {
    result.nativeNotificationsEnabled = candidate.nativeNotificationsEnabled;
  }
  if (typeof candidate.notificationMode === 'string' && (candidate.notificationMode === 'always' || candidate.notificationMode === 'hidden-only')) {
    result.notificationMode = candidate.notificationMode;
  }
  if (typeof candidate.notifyOnSubtasks === 'boolean') {
    result.notifyOnSubtasks = candidate.notifyOnSubtasks;
  }
  if (typeof candidate.notifyOnCompletion === 'boolean') {
    result.notifyOnCompletion = candidate.notifyOnCompletion;
  }
  if (typeof candidate.notifyOnError === 'boolean') {
    result.notifyOnError = candidate.notifyOnError;
  }
  if (typeof candidate.notifyOnQuestion === 'boolean') {
    result.notifyOnQuestion = candidate.notifyOnQuestion;
  }
  if (candidate.notificationTemplates && typeof candidate.notificationTemplates === 'object') {
    const templates = candidate.notificationTemplates as Record<string, unknown>;
    const validateTemplate = (key: string): { title: string; message: string } | undefined => {
      const value = templates[key];
      if (!value || typeof value !== 'object') return undefined;
      const obj = value as Record<string, unknown>;
      const title = typeof obj.title === 'string' ? obj.title : '';
      const message = typeof obj.message === 'string' ? obj.message : '';
      return { title, message };
    };
    const completion = validateTemplate('completion');
    const error = validateTemplate('error');
    const question = validateTemplate('question');
    const subtask = validateTemplate('subtask');
    if (completion || error || question || subtask) {
      result.notificationTemplates = {
        completion: completion ?? { title: 'Task Complete', message: 'Your task has finished.' },
        error: error ?? { title: 'Error Occurred', message: 'An error occurred while processing your task.' },
        question: question ?? { title: 'Input Needed', message: 'Please provide input to continue.' },
        subtask: subtask ?? { title: 'Subtask Complete', message: 'A subtask has finished.' },
      };
    }
  }
  if (typeof candidate.summarizeLastMessage === 'boolean') {
    result.summarizeLastMessage = candidate.summarizeLastMessage;
  }
  if (typeof candidate.summaryThreshold === 'number' && Number.isFinite(candidate.summaryThreshold)) {
    result.summaryThreshold = Math.max(0, Math.round(candidate.summaryThreshold));
  }
  if (typeof candidate.summaryLength === 'number' && Number.isFinite(candidate.summaryLength)) {
    result.summaryLength = Math.max(10, Math.round(candidate.summaryLength));
  }
  if (typeof candidate.maxLastMessageLength === 'number' && Number.isFinite(candidate.maxLastMessageLength)) {
    result.maxLastMessageLength = Math.max(10, Math.round(candidate.maxLastMessageLength));
  }
  if (candidate.usageDisplayMode === 'usage' || candidate.usageDisplayMode === 'remaining') {
    result.usageDisplayMode = candidate.usageDisplayMode;
  }
  if (Array.isArray(candidate.usageDropdownProviders)) {
    result.usageDropdownProviders = candidate.usageDropdownProviders.filter(
      (entry): entry is string => typeof entry === 'string' && entry.length > 0
    );
  }

  // Parse usageSelectedModels (Record<string, string[]>)
  if (candidate.usageSelectedModels && typeof candidate.usageSelectedModels === 'object') {
    const selectedModels: Record<string, string[]> = {};
    for (const [providerId, models] of Object.entries(candidate.usageSelectedModels)) {
      if (Array.isArray(models)) {
        selectedModels[providerId] = models.filter((m): m is string => typeof m === 'string');
      }
    }
    if (Object.keys(selectedModels).length > 0) {
      result.usageSelectedModels = selectedModels;
    }
  }

  // Parse usageCollapsedFamilies (Record<string, string[]>)
  if (candidate.usageCollapsedFamilies && typeof candidate.usageCollapsedFamilies === 'object') {
    const collapsedFamilies: Record<string, string[]> = {};
    for (const [providerId, families] of Object.entries(candidate.usageCollapsedFamilies)) {
      if (Array.isArray(families)) {
        collapsedFamilies[providerId] = families.filter((f): f is string => typeof f === 'string');
      }
    }
    if (Object.keys(collapsedFamilies).length > 0) {
      result.usageCollapsedFamilies = collapsedFamilies;
    }
  }

  // Parse usageExpandedFamilies (Record<string, string[]>) - inverted collapsed logic for header dropdown
  if (candidate.usageExpandedFamilies && typeof candidate.usageExpandedFamilies === 'object') {
    const expandedFamilies: Record<string, string[]> = {};
    for (const [providerId, families] of Object.entries(candidate.usageExpandedFamilies)) {
      if (Array.isArray(families)) {
        expandedFamilies[providerId] = families.filter((f): f is string => typeof f === 'string');
      }
    }
    if (Object.keys(expandedFamilies).length > 0) {
      result.usageExpandedFamilies = expandedFamilies;
    }
  }

  // Parse usageModelGroups - custom model groups configuration per provider
  if (candidate.usageModelGroups && typeof candidate.usageModelGroups === 'object') {
    const modelGroups: Record<string, {
      customGroups?: Array<{id: string; label: string; models: string[]; order: number}>;
      modelAssignments?: Record<string, string>;
      renamedGroups?: Record<string, string>;
    }> = {};
    for (const [providerId, config] of Object.entries(candidate.usageModelGroups)) {
      if (config && typeof config === 'object') {
        const typedConfig = config as Record<string, unknown>;
        const providerConfig: NonNullable<DesktopSettings['usageModelGroups']>[string] = {};

        // Parse customGroups
        if (Array.isArray(typedConfig.customGroups)) {
          providerConfig.customGroups = typedConfig.customGroups
            .filter((g): g is Record<string, unknown> => g && typeof g === 'object')
            .map((g) => ({
              id: String(g.id ?? ''),
              label: String(g.label ?? ''),
              models: Array.isArray(g.models)
                ? g.models.filter((m): m is string => typeof m === 'string')
                : [],
              order: typeof g.order === 'number' ? g.order : 0,
            }));
        }

        // Parse modelAssignments
        if (typedConfig.modelAssignments && typeof typedConfig.modelAssignments === 'object') {
          providerConfig.modelAssignments = Object.fromEntries(
            Object.entries(typedConfig.modelAssignments as Record<string, unknown>)
              .filter(([, v]) => typeof v === 'string')
              .map(([k, v]) => [k, String(v)])
          );
        }

        // Parse renamedGroups
        if (typedConfig.renamedGroups && typeof typedConfig.renamedGroups === 'object') {
          providerConfig.renamedGroups = Object.fromEntries(
            Object.entries(typedConfig.renamedGroups as Record<string, unknown>)
              .filter(([, v]) => typeof v === 'string')
              .map(([k, v]) => [k, String(v)])
          );
        }

        if (Object.keys(providerConfig).length > 0) {
          modelGroups[providerId] = providerConfig;
        }
      }
    }
    if (Object.keys(modelGroups).length > 0) {
      result.usageModelGroups = modelGroups;
    }
  }

  if (typeof candidate.inputSpellcheckEnabled === 'boolean') {
    result.inputSpellcheckEnabled = candidate.inputSpellcheckEnabled;
  }
  if (typeof candidate.showOpenCodeUpdateNotifications === 'boolean') {
    result.showOpenCodeUpdateNotifications = candidate.showOpenCodeUpdateNotifications;
  }
  if (typeof candidate.agentControlToolEnabled === 'boolean') {
    result.agentControlToolEnabled = candidate.agentControlToolEnabled;
  }
  if (typeof candidate.agentWebToolEnabled === 'boolean') {
    result.agentWebToolEnabled = candidate.agentWebToolEnabled;
  }
  if (typeof candidate.agentMemoryToolEnabled === 'boolean') {
    result.agentMemoryToolEnabled = candidate.agentMemoryToolEnabled;
  }
  if (typeof candidate.openCodeUpdateToastDismissedVersion === 'string') {
    result.openCodeUpdateToastDismissedVersion = candidate.openCodeUpdateToastDismissedVersion.trim().slice(0, 128);
  }
  if (typeof candidate.showToolFileIcons === 'boolean') {
    result.showToolFileIcons = candidate.showToolFileIcons;
  }
  if (typeof candidate.codeBlockLineWrap === 'boolean') {
    result.codeBlockLineWrap = candidate.codeBlockLineWrap;
  }
  if (typeof candidate.showTurnChangedFiles === 'boolean') {
    result.showTurnChangedFiles = candidate.showTurnChangedFiles;
  }
  if (typeof candidate.showExpandedBashTools === 'boolean') {
    result.showExpandedBashTools = candidate.showExpandedBashTools;
  }
  if (typeof candidate.showExpandedEditTools === 'boolean') {
    result.showExpandedEditTools = candidate.showExpandedEditTools;
  }
  if (typeof candidate.timeFormatPreference === 'string'
    && (candidate.timeFormatPreference === 'auto' || candidate.timeFormatPreference === '12h' || candidate.timeFormatPreference === '24h')) {
    result.timeFormatPreference = candidate.timeFormatPreference;
  }
  if (typeof candidate.weekStartPreference === 'string'
    && (candidate.weekStartPreference === 'auto' || candidate.weekStartPreference === 'sunday' || candidate.weekStartPreference === 'monday')) {
    result.weekStartPreference = candidate.weekStartPreference;
  }
  if (typeof candidate.desktopWindowControlsPosition === 'string') {
    if (candidate.desktopWindowControlsPosition === 'left') {
      result.desktopWindowControlsPosition = 'left';
    } else if (
      candidate.desktopWindowControlsPosition === 'right'
      || candidate.desktopWindowControlsPosition === 'auto'
    ) {
      // Legacy "auto" never read OS chrome config; treat as right.
      result.desktopWindowControlsPosition = 'right';
    }
  }
  if (typeof candidate.desktopWindowControlsStyle === 'string') {
    if (candidate.desktopWindowControlsStyle === 'classic' || candidate.desktopWindowControlsStyle === 'traffic-lights') {
      result.desktopWindowControlsStyle = candidate.desktopWindowControlsStyle;
    }
  }
  if (typeof candidate.chatRenderMode === 'string'
    && (candidate.chatRenderMode === 'sorted' || candidate.chatRenderMode === 'live')) {
    result.chatRenderMode = candidate.chatRenderMode;
  }
  if (typeof candidate.messageStreamTransport === 'string'
    && (candidate.messageStreamTransport === 'auto' || candidate.messageStreamTransport === 'ws' || candidate.messageStreamTransport === 'sse')) {
    result.messageStreamTransport = candidate.messageStreamTransport;
  }
  if (typeof candidate.activityRenderMode === 'string'
    && (candidate.activityRenderMode === 'collapsed' || candidate.activityRenderMode === 'summary')) {
    result.activityRenderMode = candidate.activityRenderMode;
  }
  if (typeof candidate.mermaidRenderingMode === 'string'
    && (candidate.mermaidRenderingMode === 'svg' || candidate.mermaidRenderingMode === 'ascii')) {
    result.mermaidRenderingMode = candidate.mermaidRenderingMode;
  }
  if (typeof candidate.userMessageRenderingMode === 'string'
    && (candidate.userMessageRenderingMode === 'markdown' || candidate.userMessageRenderingMode === 'plain')) {
    result.userMessageRenderingMode = candidate.userMessageRenderingMode;
  }
  if (typeof candidate.collapsibleUserMessages === 'boolean') {
    result.collapsibleUserMessages = candidate.collapsibleUserMessages;
  }
  if (typeof candidate.stickyUserHeader === 'boolean') {
    result.stickyUserHeader = candidate.stickyUserHeader;
  }
  if (typeof candidate.promptNavigatorEnabled === 'boolean') {
    result.promptNavigatorEnabled = candidate.promptNavigatorEnabled;
  }
  if (typeof candidate.wideChatLayoutEnabled === 'boolean') {
    result.wideChatLayoutEnabled = candidate.wideChatLayoutEnabled;
  }
  if (typeof candidate.showSplitAssistantMessageActions === 'boolean') {
    result.showSplitAssistantMessageActions = candidate.showSplitAssistantMessageActions;
  }
  if (typeof candidate.fontSize === 'number' && Number.isFinite(candidate.fontSize)) {
    result.fontSize = candidate.fontSize;
  }
  if (typeof candidate.terminalFontSize === 'number' && Number.isFinite(candidate.terminalFontSize)) {
    result.terminalFontSize = candidate.terminalFontSize;
  }
  if (isTerminalShell(candidate.terminalShell)) {
    result.terminalShell = candidate.terminalShell;
  }
  if (Array.isArray(candidate.terminalLoginShells)) {
    result.terminalLoginShells = [...new Set(candidate.terminalLoginShells.filter(isTerminalShell))];
  }
  if (typeof candidate.editorFontSize === 'number' && Number.isFinite(candidate.editorFontSize)) {
    result.editorFontSize = candidate.editorFontSize;
  }
  if (isUiFontOption(candidate.uiFont)) {
    result.uiFont = candidate.uiFont;
  }
  if (isMonoFontOption(candidate.monoFont)) {
    result.monoFont = candidate.monoFont;
  }
  if (typeof candidate.padding === 'number' && Number.isFinite(candidate.padding)) {
    result.padding = candidate.padding;
  }
  if (typeof candidate.cornerRadius === 'number' && Number.isFinite(candidate.cornerRadius)) {
    result.cornerRadius = candidate.cornerRadius;
  }
  if (typeof candidate.inputBarOffset === 'number' && Number.isFinite(candidate.inputBarOffset)) {
    result.inputBarOffset = candidate.inputBarOffset;
  }
  const shortcutOverrides = sanitizeShortcutOverrides(candidate.shortcutOverrides);
  if (shortcutOverrides) {
    result.shortcutOverrides = shortcutOverrides;
  }
  if (typeof candidate.mobileKeyboardMode === 'string') {
    if (candidate.mobileKeyboardMode === 'native' || candidate.mobileKeyboardMode === 'resize-content') {
      result.mobileKeyboardMode = candidate.mobileKeyboardMode;
    }
  }

  const favoriteModels = sanitizeModelRefs(candidate.favoriteModels, 64);
  if (favoriteModels) {
    result.favoriteModels = favoriteModels;
  }

  const hiddenModels = sanitizeModelRefs(candidate.hiddenModels, 1024);
  if (hiddenModels) {
    result.hiddenModels = hiddenModels;
  }

  const collapsedModelProviders = sanitizeStringArray(candidate.collapsedModelProviders);
  if (collapsedModelProviders) {
    result.collapsedModelProviders = collapsedModelProviders;
  }

  const recentModels = sanitizeModelRefs(candidate.recentModels, 16);
  if (recentModels) {
    result.recentModels = recentModels;
  }

  const recentAgents = sanitizeStringArray(candidate.recentAgents);
  if (recentAgents) {
    result.recentAgents = recentAgents;
  }

  const recentEfforts = sanitizeRecentEfforts(candidate.recentEfforts);
  if (recentEfforts) {
    result.recentEfforts = recentEfforts;
  }
  if (
    typeof candidate.diffLayoutPreference === 'string'
    && (candidate.diffLayoutPreference === 'dynamic'
      || candidate.diffLayoutPreference === 'inline'
      || candidate.diffLayoutPreference === 'side-by-side')
  ) {
    result.diffLayoutPreference = candidate.diffLayoutPreference;
  }
  if (
    typeof candidate.gitChangesViewMode === 'string'
    && (candidate.gitChangesViewMode === 'flat' || candidate.gitChangesViewMode === 'tree')
  ) {
    result.gitChangesViewMode = candidate.gitChangesViewMode;
  }
  if (typeof candidate.directoryShowHidden === 'boolean') {
    result.directoryShowHidden = candidate.directoryShowHidden;
  }
  if (typeof candidate.filesViewShowGitignored === 'boolean') {
    result.filesViewShowGitignored = candidate.filesViewShowGitignored;
  }
  if (typeof candidate.openInAppId === 'string' && candidate.openInAppId.length > 0) {
    result.openInAppId = candidate.openInAppId;
  }
  if (typeof candidate.pwaAppName === 'string') {
    const normalized = candidate.pwaAppName.trim().replace(/\s+/g, ' ').slice(0, 64);
    result.pwaAppName = normalized.length > 0 ? normalized : '';
  }

  const skillCatalogs = sanitizeSkillCatalogs(candidate.skillCatalogs);
  if (skillCatalogs) {
    result.skillCatalogs = skillCatalogs;
  }

  if (typeof candidate.reportUsage === 'boolean') {
    result.reportUsage = candidate.reportUsage;
  }

  if (typeof candidate.globalBehaviorPrompt === 'string') {
    result.globalBehaviorPrompt = candidate.globalBehaviorPrompt;
  }
  if (typeof candidate.responseStyleEnabled === 'boolean') {
    result.responseStyleEnabled = candidate.responseStyleEnabled;
  }
  if (
    typeof candidate.responseStylePreset === 'string'
    && (candidate.responseStylePreset === 'concise'
      || candidate.responseStylePreset === 'detailed'
      || candidate.responseStylePreset === 'mentor'
      || candidate.responseStylePreset === 'pushback'
      || candidate.responseStylePreset === 'noFiller'
      || candidate.responseStylePreset === 'matchEnergy'
      || candidate.responseStylePreset === 'warmPeer'
      || candidate.responseStylePreset === 'custom')
  ) {
    result.responseStylePreset = candidate.responseStylePreset;
  }
  if (typeof candidate.responseStyleCustomInstructions === 'string') {
    result.responseStyleCustomInstructions = candidate.responseStyleCustomInstructions;
  }
  if (typeof candidate.dictationEnabled === 'boolean') {
    result.dictationEnabled = candidate.dictationEnabled;
  }
  if (candidate.sttProvider === 'local' || candidate.sttProvider === 'openai-compatible') {
    result.sttProvider = candidate.sttProvider;
  } else if (candidate.sttProvider === 'server') {
    // Legacy provider migration: 'server' was the OpenAI-compatible endpoint.
    result.sttProvider = 'openai-compatible';
  } else if (candidate.sttProvider === 'browser' || candidate.sttProvider === 'wasm') {
    result.sttProvider = 'local';
  }
  if (typeof candidate.sttServerUrl === 'string') {
    result.sttServerUrl = candidate.sttServerUrl.trim();
  }
  if (typeof candidate.sttModel === 'string') {
    result.sttModel = candidate.sttModel.trim();
  }
  if (typeof candidate.sttLocalModel === 'string') {
    result.sttLocalModel = candidate.sttLocalModel.trim();
  }
  if (typeof candidate.sttLanguage === 'string') {
    result.sttLanguage = candidate.sttLanguage.trim();
  }

  return result;
};

type SettingsRuntimeContext = { runtimeKey: string; generation: number };

// Short-lived cache + in-flight dedup for settings fetches to avoid repeated GET calls during startup
let _settingsRuntimeGeneration = 0;
let _settingsCache: { value: DesktopSettings | null; at: number; context: SettingsRuntimeContext } | null = null;
let _settingsInflight: { promise: Promise<DesktopSettings | null>; context: SettingsRuntimeContext } | null = null;
let _pendingSettingsChanges: Partial<DesktopSettings> | null = null;
let _pendingSettingsContext: SettingsRuntimeContext | null = null;
let _settingsFlushTimer: ReturnType<typeof setTimeout> | null = null;
let _settingsFlushWaiters: Array<() => void> = [];
let _settingsLifecycleInitialized = false;
const SETTINGS_CACHE_TTL = 2_000; // 2 seconds — covers the startup burst
const SETTINGS_DEBOUNCE_MS = 200;

const captureSettingsRuntimeContext = (): SettingsRuntimeContext => ({
  runtimeKey: getRuntimeKey(),
  generation: _settingsRuntimeGeneration,
});

const isSameSettingsRuntimeContext = (left: SettingsRuntimeContext, right: SettingsRuntimeContext): boolean => (
  left.runtimeKey === right.runtimeKey && left.generation === right.generation
);

const isSettingsRuntimeContextCurrent = (context: SettingsRuntimeContext): boolean => (
  context.generation === _settingsRuntimeGeneration && context.runtimeKey === getRuntimeKey()
);

const ensureSettingsRuntimeLifecycle = (): void => {
  if (_settingsLifecycleInitialized || typeof window === 'undefined') return;
  _settingsLifecycleInitialized = true;

  subscribeRuntimeEndpointWillChange((detail) => {
    if (detail.runtimeKey === detail.previousRuntimeKey) return;
    if (_settingsFlushTimer) clearTimeout(_settingsFlushTimer);
    if (_pendingSettingsChanges) void _flushSettingsUpdate();
  });
  subscribeRuntimeEndpointChanged((detail) => {
    if (detail.runtimeKey === detail.previousRuntimeKey) return;
    _settingsRuntimeGeneration += 1;
    _settingsCache = null;
    _settingsInflight = null;
  });
};

const fetchWebSettings = async (context = captureSettingsRuntimeContext()): Promise<DesktopSettings | null> => {
  ensureSettingsRuntimeLifecycle();
  // Return cached if fresh
  if (_settingsCache && isSameSettingsRuntimeContext(_settingsCache.context, context) && Date.now() - _settingsCache.at < SETTINGS_CACHE_TTL) {
    return _settingsCache.value;
  }

  // Dedup concurrent calls
  if (_settingsInflight && isSameSettingsRuntimeContext(_settingsInflight.context, context)) return _settingsInflight.promise;

  const inflight = {
    context,
    promise: (async (): Promise<DesktopSettings | null> => {
      const runtimeSettings = getRuntimeSettingsAPI();
      if (runtimeSettings) {
        try {
          const result = await runtimeSettings.load();
          if (!isSettingsRuntimeContextCurrent(context)) return null;
          const settings = sanitizeWebSettings(result.settings);
          _settingsCache = { value: settings, at: Date.now(), context };
          return settings;
        } catch (error) {
          if (!isSettingsRuntimeContextCurrent(context)) return null;
          console.warn('Failed to load shared settings from runtime settings API:', error);
        }
      }

      if (!isSettingsRuntimeContextCurrent(context)) return null;
      try {
        const response = await runtimeFetch('/api/config/settings', {
          method: 'GET',
          headers: { Accept: 'application/json' },
        });
        if (!isSettingsRuntimeContextCurrent(context)) return null;
        if (!response.ok) {
          return null;
        }
        const data = await response.json().catch(() => null);
        if (!isSettingsRuntimeContextCurrent(context)) return null;
        const settings = sanitizeWebSettings(data);
        _settingsCache = { value: settings, at: Date.now(), context };
        return settings;
      } catch (error) {
        if (!isSettingsRuntimeContextCurrent(context)) return null;
        console.warn('Failed to load shared settings from server:', error);
        return null;
      }
    })(),
  };
  _settingsInflight = inflight;
  void inflight.promise.finally(() => {
    if (_settingsInflight === inflight) _settingsInflight = null;
  });

  return inflight.promise;
};

/** Invalidate cached settings (call after a successful PUT) */
export const invalidateSettingsCache = (): void => {
  _settingsCache = null;
};

export const syncDesktopSettings = async (): Promise<void> => {
  if (typeof window === 'undefined') {
    return;
  }
  ensureSettingsRuntimeLifecycle();
  const context = captureSettingsRuntimeContext();

  const persistApis = [getPersistApi(), useSessionDisplayStore.persist];

  // Wait for Zustand persist hydration before applying server settings.
  // Otherwise `set()`-calls race with hydration: we set X, then hydration
  // reads localStorage and overwrites back to the persisted value.
  const waitForPersistHydration = (persistApi: PersistApi | undefined): Promise<void> => {
    if (!persistApi?.hasHydrated || persistApi.hasHydrated()) {
      return Promise.resolve();
    }
    if (!persistApi.onFinishHydration) {
      return Promise.resolve();
    }
    return new Promise<void>((resolve) => {
      let settled = false;
      const finish = () => {
        if (settled) return;
        settled = true;
        resolve();
      };
      const unsubscribe = persistApi.onFinishHydration!(() => {
        unsubscribe?.();
        finish();
      });
      // Guard: hydration may have flipped to true between the hasHydrated
      // check and the onFinishHydration subscription — resolve immediately.
      if (persistApi.hasHydrated?.()) finish();
    });
  };
  const waitForHydration = (): Promise<void> => Promise.all(
    persistApis.map(waitForPersistHydration),
  ).then(() => undefined);

  // Each step is wrapped in try/catch so a failure in one side-effect (e.g.
  // a TypeError from writing to a contextBridge-protected global) doesn't
  // prevent server settings from reaching the Zustand store.
  const applySettings = async (settings: DesktopSettings) => {
    if (!isSettingsRuntimeContextCurrent(context)) return;
    const shouldPersistCraftGoalMigration = settings.draftStartersCraftGoalAdded !== true
      || settings.draftStartersScheduleTaskAdded !== true;
    // `autoSaveEnabled` is new to the settings backend. Until the server has a
    // value, materialize would invent the client default (true) and overwrite a
    // deliberate legacy "off" preference migrated from
    // `openchamber:files:auto-save-enabled`. Prefer the hydrated store value and
    // seed the backend once so later omitted→default authority is correct.
    const shouldSeedAutoSaveEnabled = typeof settings.autoSaveEnabled !== 'boolean';
    const shouldSeedSidebarProjectDisplayMode = settings.sidebarProjectDisplayMode === undefined;
    const shouldSeedSidebarSessionGroupingMode = settings.sidebarSessionGroupingMode === undefined;
    const shouldSeedSidebarProjectSortOrder = settings.sidebarProjectSortOrder === undefined;
    const shouldSeedSidebarShowRecentSection = settings.sidebarShowRecentSection === undefined;
    const authoritativeSettings = materializeAuthoritativeUiSettings(settings);
    try {
      persistToLocalStorage(settings);
    } catch (error) {
      console.warn('persistToLocalStorage failed:', error);
    }
    await waitForHydration();
    if (!isSettingsRuntimeContextCurrent(context)) return;
    if (shouldSeedAutoSaveEnabled) {
      authoritativeSettings.autoSaveEnabled = useUIStore.getState().autoSaveEnabled;
    }
    const sessionDisplayState = useSessionDisplayStore.getState();
    if (shouldSeedSidebarProjectDisplayMode) {
      authoritativeSettings.sidebarProjectDisplayMode = sessionDisplayState.projectDisplayMode;
    }
    if (shouldSeedSidebarSessionGroupingMode) {
      authoritativeSettings.sidebarSessionGroupingMode = sessionDisplayState.sessionGroupingMode;
    }
    if (shouldSeedSidebarProjectSortOrder) {
      authoritativeSettings.sidebarProjectSortOrder = sessionDisplayState.projectSortOrder;
    }
    if (shouldSeedSidebarShowRecentSection) {
      authoritativeSettings.sidebarShowRecentSection = sessionDisplayState.showRecentSection;
    }
    if (settings.draftStarters === undefined) {
      useUIStore.setState({ globalDraftStarters: null });
    }
    try {
      applyDesktopUiPreferences(authoritativeSettings);
    } catch (error) {
      console.warn('applyDesktopUiPreferences failed:', error);
    }
    const migrationPatch: Partial<DesktopSettings> = {};
    if (shouldPersistCraftGoalMigration) {
      if (authoritativeSettings.draftStarters) {
        migrationPatch.draftStarters = authoritativeSettings.draftStarters;
      }
      migrationPatch.draftStartersCraftGoalAdded = true;
      migrationPatch.draftStartersScheduleTaskAdded = true;
    }
    if (shouldSeedAutoSaveEnabled) {
      migrationPatch.autoSaveEnabled = authoritativeSettings.autoSaveEnabled;
    }
    if (shouldSeedSidebarProjectDisplayMode) {
      migrationPatch.sidebarProjectDisplayMode = authoritativeSettings.sidebarProjectDisplayMode;
    }
    if (shouldSeedSidebarSessionGroupingMode) {
      migrationPatch.sidebarSessionGroupingMode = authoritativeSettings.sidebarSessionGroupingMode;
    }
    if (shouldSeedSidebarProjectSortOrder) {
      migrationPatch.sidebarProjectSortOrder = authoritativeSettings.sidebarProjectSortOrder;
    }
    if (shouldSeedSidebarShowRecentSection) {
      migrationPatch.sidebarShowRecentSection = authoritativeSettings.sidebarShowRecentSection;
    }
    if (Object.keys(migrationPatch).length > 0) {
      await updateDesktopSettings(migrationPatch);
      if (!isSettingsRuntimeContextCurrent(context)) return;
    }

    dispatchSettingsSynced(authoritativeSettings);
  };

  try {
    const webSettings = await fetchWebSettings(context);
    if (webSettings && isSettingsRuntimeContextCurrent(context)) {
      await applySettings(webSettings);
    }
  } catch (error) {
    console.warn('Failed to synchronise settings:', error);
  }
};

// Coalesce rapid updateDesktopSettings calls into a single PUT
async function _flushSettingsUpdate(): Promise<void> {
  const changes = _pendingSettingsChanges;
  const context = _pendingSettingsContext;
  const waiters = _settingsFlushWaiters;
  _pendingSettingsChanges = null;
  _pendingSettingsContext = null;
  _settingsFlushTimer = null;
  _settingsFlushWaiters = [];
  try {
    if (!changes || !context || Object.keys(changes).length === 0 || !isSettingsRuntimeContextCurrent(context)) {
      // Nothing will be written — clear any pending "Saving…" indicator.
      dispatchSettingsSaveState('saved');
      return;
    }

    const runtimeSettings = getRuntimeSettingsAPI();
    if (runtimeSettings) {
      try {
        const updated = await runtimeSettings.save(changes);
        if (!isSettingsRuntimeContextCurrent(context)) return;
        if (updated) {
          applyDesktopUiPreferences(updated);
          dispatchSettingsSynced(updated);
          _settingsCache = null;
        }
        dispatchSettingsSaveState(updated ? 'saved' : 'error');
        return;
      } catch (error) {
        if (!isSettingsRuntimeContextCurrent(context)) return;
        console.warn('Failed to update settings via runtime settings API:', error);
      }
    }

    if (!isSettingsRuntimeContextCurrent(context)) return;
    try {
      const response = await runtimeFetch('/api/config/settings', {
        method: 'PUT',
        headers: {
          'Content-Type': 'application/json',
          Accept: 'application/json',
        },
        body: JSON.stringify(changes),
      });

      if (!isSettingsRuntimeContextCurrent(context)) return;
      if (!response.ok) {
        console.warn('Failed to update shared settings via API:', response.status, response.statusText);
        dispatchSettingsSaveState('error');
        return;
      }

      const updated = sanitizeWebSettings(await response.json().catch(() => null));
      if (!isSettingsRuntimeContextCurrent(context)) return;
      if (updated) {
        applyDesktopUiPreferences(updated);
        dispatchSettingsSynced(updated);
        dispatchSettingsSaveState('saved');
        // Invalidate GET cache so next read sees the fresh data
        _settingsCache = null;
      } else {
        dispatchSettingsSaveState('error');
      }
    } catch (error) {
      if (isSettingsRuntimeContextCurrent(context)) {
        console.warn('Failed to update shared settings via API:', error);
        dispatchSettingsSaveState('error');
      }
    }
  } finally {
    waiters.forEach((resolve) => resolve());
  }
}

export const updateDesktopSettings = async (changes: Partial<DesktopSettings>): Promise<void> => {
  if (typeof window === 'undefined') {
    return;
  }
  ensureSettingsRuntimeLifecycle();
  const context = captureSettingsRuntimeContext();

  if (_pendingSettingsContext && !isSameSettingsRuntimeContext(_pendingSettingsContext, context)) {
    if (_settingsFlushTimer) clearTimeout(_settingsFlushTimer);
    void _flushSettingsUpdate();
  }

  _pendingSettingsChanges = { ...(_pendingSettingsChanges ?? {}), ...changes };
  _pendingSettingsContext = context;
  dispatchSettingsSaveState('saving');

  if (_settingsFlushTimer) {
    clearTimeout(_settingsFlushTimer);
  }
  const flushed = new Promise<void>((resolve) => {
    _settingsFlushWaiters.push(resolve);
  });
  _settingsFlushTimer = setTimeout(() => void _flushSettingsUpdate(), SETTINGS_DEBOUNCE_MS);
  return flushed;
};

export const initializeAppearancePreferences = async (): Promise<void> => {
  if (typeof window === 'undefined') {
    return;
  }

  const persistApi = getPersistApi();

  try {
    const appearance = await loadAppearancePreferences();
    if (!appearance) {
      return;
    }

    const applyAppearance = () => applyAppearancePreferences(appearance);

    if (persistApi?.hasHydrated?.()) {
      applyAppearance();
      return;
    }

    applyAppearance();
    if (persistApi?.onFinishHydration) {
      const unsubscribe = persistApi.onFinishHydration(() => {
        unsubscribe?.();
        applyAppearance();
      });
    }
  } catch (error) {
    console.warn('Failed to load appearance preferences:', error);
  }
};