State Management

State Architecture

Off Grid uses Zustand for state management with AsyncStorage persistence. State is split across five stores, each with a single responsibility.

Store Overview

Store	Purpose	Persistence
appStore	Models, settings, hardware info, gallery	✅ Yes
chatStore	Conversations, messages, streaming state	✅ Partial (conversations only)
projectStore	Custom system prompts (projects)	✅ Yes
authStore	Passphrase lock state	✅ Yes
whisperStore	Whisper model selection	✅ Yes

appStore

Path: src/stores/appStore.ts:122 Responsibilities:

Downloaded models (text, image, Whisper)
Active model IDs
Settings (temperature, context length, GPU config, image gen params)
Device hardware info (RAM, CPU)
Gallery (generated images metadata)
Background generation state (progress, status, preview path)

Schema

interface AppState {
  // Theme
  themeMode: 'system' | 'light' | 'dark';

  // Onboarding
  hasCompletedOnboarding: boolean;
  onboardingChecklist: OnboardingChecklist;
  checklistDismissed: boolean;

  // Device info
  deviceInfo: DeviceInfo | null;
  modelRecommendation: ModelRecommendation | null;

  // Text models
  downloadedModels: DownloadedModel[];
  activeModelId: string | null;
  modelMaxContext: number | null;

  // Image models
  downloadedImageModels: ONNXImageModel[];
  activeImageModelId: string | null;

  // Download tracking
  downloadProgress: Record<string, DownloadProgressInfo>;
  activeBackgroundDownloads: Record<number, PersistedDownloadInfo>;

  // Settings
  settings: AppSettings;

  // Image generation state
  isGeneratingImage: boolean;
  imageGenerationProgress: { step: number; totalSteps: number } | null;
  imageGenerationStatus: string | null;
  imagePreviewPath: string | null;

  // Gallery
  generatedImages: GeneratedImage[];
}

Key Actions

Model Management:

addDownloadedModel(model: DownloadedModel);
removeDownloadedModel(modelId: string);
setActiveModelId(modelId: string | null);

Settings:

updateSettings(settings: Partial<AppSettings>);
resetSettings();

Gallery:

addGeneratedImage(image: GeneratedImage);
removeGeneratedImage(imageId: string);
removeImagesByConversationId(conversationId: string);

Persistence Strategy

export const useAppStore = create<AppState>()(
  persist(
    (set, get) => ({
      // ... state and actions
    }),
    {
      name: 'local-llm-app-storage',
      storage: createJSONStorage(() => AsyncStorage),
      partialize: (state) => ({
        themeMode: state.themeMode,
        hasCompletedOnboarding: state.hasCompletedOnboarding,
        activeModelId: state.activeModelId,
        settings: state.settings,
        activeImageModelId: state.activeImageModelId,
        generatedImages: state.generatedImages,
        // ... other persisted fields
      }),
    }
  )
);

What is NOT persisted:

downloadProgress (ephemeral download state)
deviceInfo (recalculated on app start)
isGeneratingImage, imageGenerationProgress, imageGenerationStatus (runtime state)

chatStore

Path: src/stores/chatStore.ts:48 Responsibilities:

Conversations (title, messages, metadata)
Streaming state (current streaming message, thinking indicator)
Message operations (add, update, delete)

Schema

interface ChatState {
  // Conversations
  conversations: Conversation[];
  activeConversationId: string | null;

  // Streaming state (NOT persisted)
  streamingMessage: string;
  streamingForConversationId: string | null;
  isStreaming: boolean;
  isThinking: boolean;
}

Key Actions

Conversation Management:

createConversation(modelId: string, title?: string, projectId?: string): string;
deleteConversation(conversationId: string);
setActiveConversation(conversationId: string | null);
setConversationProject(conversationId: string, projectId: string | null);

Message Operations:

addMessage(conversationId: string, message: Omit<Message, 'id' | 'timestamp'>): Message;
updateMessageContent(conversationId: string, messageId: string, content: string);
deleteMessage(conversationId: string, messageId: string);
deleteMessagesAfter(conversationId: string, messageId: string); // Branch from message

Streaming:

startStreaming(conversationId: string);
appendToStreamingMessage(token: string);
finalizeStreamingMessage(conversationId: string, generationTimeMs?: number, meta?: GenerationMeta);
clearStreamingMessage();

Persistence Strategy

export const useChatStore = create<ChatState>()(
  persist(
    (set, get) => ({
      // ... state and actions
    }),
    {
      name: 'local-llm-chat-storage',
      storage: createJSONStorage(() => AsyncStorage),
      partialize: (state) => ({
        conversations: state.conversations,
        activeConversationId: state.activeConversationId,
        // Streaming state NOT persisted (transient)
      }),
    }
  )
);

Streaming State is NOT Persisted: Rationale: If the app crashes mid-generation, the partial streaming message is lost. On restart, the conversation shows the last finalized message. Conversation Title Auto-Generation:

addMessage: (conversationId, messageData) => {
  const message: Message = {
    id: generateId(),
    ...messageData,
    timestamp: Date.now(),
  };

  set((state) => ({
    conversations: state.conversations.map((conv) =>
      conv.id === conversationId
        ? {
            ...conv,
            messages: [...conv.messages, message],
            updatedAt: new Date().toISOString(),
            // Update title from first user message if still default
            title: conv.title === 'New Conversation' && messageData.role === 'user'
              ? messageData.content.slice(0, 50) + (messageData.content.length > 50 ? '...' : '')
              : conv.title,
          }
        : conv
    ),
  }));

  return message;
}

projectStore

Path: src/stores/projectStore.ts Responsibilities:

Custom system prompts (called “projects”)
Active project selection

Projects allow users to define reusable system prompts (e.g., “Python Tutor”, “Creative Writer”) that apply to conversations.

Schema

interface Project {
  id: string;
  name: string;
  systemPrompt: string;
  createdAt: string;
  updatedAt: string;
}

interface ProjectState {
  projects: Project[];
  activeProjectId: string | null;
}

Key Actions

createProject(name: string, systemPrompt: string): Project;
updateProject(id: string, updates: Partial<Project>);
deleteProject(id: string);
setActiveProject(id: string | null);

authStore

Path: src/stores/authStore.ts Responsibilities:

Passphrase lock state
Authentication status

Schema

interface AuthState {
  isLocked: boolean;
  hasPassphrase: boolean;
  lockTimeout: number; // seconds
}

whisperStore

Path: src/stores/whisperStore.ts Responsibilities:

Whisper model selection (Tiny, Base, Small)
Transcription configuration

Schema

interface WhisperState {
  selectedModel: 'tiny' | 'base' | 'small';
  autoDownload: boolean;
}

Service-Store Synchronization

Services update stores to maintain UI reactivity. The pattern is unidirectional: services write to stores, UI components read from stores.

Pattern: Service Updates Store

class ImageGenerationService {
  private state: ImageGenerationState = { ... };

  private updateState(partial: Partial<ImageGenerationState>): void {
    // 1. Update service's internal state
    this.state = { ...this.state, ...partial };

    // 2. Notify service listeners (other services, background tasks)
    this.notifyListeners();

    // 3. Sync specific fields to appStore for UI reactivity
    const appStore = useAppStore.getState();
    if ('isGenerating' in partial) {
      appStore.setIsGeneratingImage(this.state.isGenerating);
    }
    if ('progress' in partial) {
      appStore.setImageGenerationProgress(this.state.progress);
    }
    if ('status' in partial) {
      appStore.setImageGenerationStatus(this.state.status);
    }
    if ('previewPath' in partial) {
      appStore.setImagePreviewPath(this.state.previewPath);
    }
  }
}

Why Both Service State AND Store State?

Service state:

Maintains generation across component unmounts
Holds complex objects not suitable for AsyncStorage persistence
Allows services to communicate with each other

Store state:

Triggers React re-renders via Zustand subscriptions
Persists critical fields to AsyncStorage
Provides global access to UI components

Data Flow Diagram

User Action
    ↓
UI Component
    ↓
Service (singleton)
    ↓
  ├─→ Native Module (inference)
  │       ↓
  │   Callbacks (progress, tokens)
  │       ↓
  └─→ Service.updateState()
          ↓
      ├─→ Notify service listeners
      └─→ Update Zustand store
              ↓
          UI re-renders

Persistence Implementation

AsyncStorage Adapter

Zustand’s persist middleware uses createJSONStorage(() => AsyncStorage) to automatically save/restore state.

import AsyncStorage from '@react-native-async-storage/async-storage';
import { create } from 'zustand';
import { persist, createJSONStorage } from 'zustand/middleware';

export const useAppStore = create<AppState>()(
  persist(
    (set, get) => ({
      // State and actions
      settings: DEFAULT_SETTINGS,
      updateSettings: (newSettings) => set((state) => ({
        settings: { ...state.settings, ...newSettings },
      })),
    }),
    {
      name: 'local-llm-app-storage', // AsyncStorage key
      storage: createJSONStorage(() => AsyncStorage),
      partialize: (state) => ({
        settings: state.settings, // Only persist settings
      }),
    }
  )
);

Persistence Keys:

Store	AsyncStorage Key
appStore	`local-llm-app-storage`
chatStore	`local-llm-chat-storage`
projectStore	`project-storage`
authStore	`auth-storage`
whisperStore	`whisper-storage`

Migration Example

When adding new fields or changing defaults, use the merge option:

persist(
  (set, get) => ({ ... }),
  {
    name: 'local-llm-app-storage',
    storage: createJSONStorage(() => AsyncStorage),
    merge: (persistedState: any, currentState) => {
      const merged = { ...currentState, ...persistedState };

      // Migrate old modelLoadingStrategy from 'memory' → 'performance'
      if (persistedState?.settings?.modelLoadingStrategy === 'memory') {
        merged.settings = {
          ...merged.settings,
          modelLoadingStrategy: 'performance'
        };
      }

      // Migrate: add cacheType if missing, derive from old flashAttn
      if (persistedState?.settings && !persistedState.settings.cacheType) {
        const oldFlashAttn = persistedState.settings.flashAttn;
        const derivedCacheType = oldFlashAttn ? 'q8_0' : 'f16';
        merged.settings = {
          ...merged.settings,
          cacheType: derivedCacheType,
          flashAttn: true
        };
      }

      return merged as AppState;
    },
  }
)

Unidirectional Data Flow

Rule: Services write to stores. UI reads from stores. UI never writes to stores directly (only via service methods). Example: Load Model Flow

1. User taps "Load Model" button
2. UI calls: activeModelService.loadTextModel('qwen-0.6b')
3. activeModelService:
   - Checks memory
   - Calls llmService.loadModel()
   - Updates loadedTextModelId
   - Calls useAppStore.getState().setActiveModelId('qwen-0.6b')
4. appStore updates activeModelId
5. UI re-renders (Zustand subscription)

Anti-Pattern (don’t do this):

// ❌ BAD: UI writes to store directly
function ModelCard({ model }) {
  const setActiveModelId = useAppStore(state => state.setActiveModelId);

  const handleLoad = () => {
    setActiveModelId(model.id); // UI directly mutates store
    // Model not actually loaded in native!
  };
}

Correct Pattern:

// ✅ GOOD: UI calls service, service updates store
function ModelCard({ model }) {
  const handleLoad = async () => {
    await activeModelService.loadTextModel(model.id);
    // Service handles: memory check, native load, store update
  };
}

Architecture

Platform Details

Performance

State Architecture

Store Overview

appStore

Schema

Key Actions

Persistence Strategy

chatStore

Schema

Key Actions

Persistence Strategy

projectStore

Schema

Key Actions

authStore

Schema

whisperStore

Schema

Service-Store Synchronization

Pattern: Service Updates Store

Why Both Service State AND Store State?

Data Flow Diagram

Persistence Implementation

AsyncStorage Adapter

Migration Example

Unidirectional Data Flow

Build docs developers (and LLMs) love

Architecture

Platform Details

Performance

​State Architecture

​Store Overview

​appStore

​Schema

​Key Actions

​Persistence Strategy

​chatStore

​Schema

​Key Actions

​Persistence Strategy

​projectStore

​Schema

​Key Actions

​authStore

​Schema

​whisperStore

​Schema

​Service-Store Synchronization

​Pattern: Service Updates Store

​Why Both Service State AND Store State?

​Data Flow Diagram

​Persistence Implementation

​AsyncStorage Adapter

​Migration Example

​Unidirectional Data Flow

Build docs developers (and LLMs) love

State Architecture

Store Overview

appStore

Schema

Key Actions

Persistence Strategy

chatStore

Schema

Key Actions

Persistence Strategy

projectStore

Schema

Key Actions

authStore

Schema

whisperStore

Schema

Service-Store Synchronization

Pattern: Service Updates Store

Why Both Service State AND Store State?

Data Flow Diagram

Persistence Implementation

AsyncStorage Adapter

Migration Example

Unidirectional Data Flow