Generated by Spark: I can auto default to flask backend with docker environment variable. If its not set used IndexedDB.

.dockerignore

@@ -0,0 +1,16 @@
+node_modules
+dist
+.git
+.github
+.env
+.env.local
+*.log
+npm-debug.log*
+yarn-debug.log*
+yarn-error.log*
+.DS_Store
+.vscode
+.idea
+backend
+data
+pids

.env.example

@@ -0,0 +1,4 @@
+# Flask Backend Configuration (Optional)
+# If set, the app will automatically use Flask backend instead of IndexedDB
+# Example: VITE_FLASK_BACKEND_URL=http://localhost:5000
+VITE_FLASK_BACKEND_URL=

BACKEND-CONFIG.md

@@ -0,0 +1,260 @@
+# Backend Configuration Guide
+
+This guide explains how to configure CodeSnippet to use different storage backends.
+
+## Storage Options
+
+CodeSnippet supports two storage backends:
+
+### 1. IndexedDB (Default)
+- **Local browser storage** using SQLite compiled to WebAssembly
+- No server required
+- Data persists only on the current device/browser
+- Best for personal use or offline scenarios
+
+### 2. Flask Backend
+- **Remote server storage** with a Flask REST API
+- Requires running a Flask backend server
+- Data accessible from any device
+- Best for team use or multi-device access
+
+## Configuration Methods
+
+### Method 1: Automatic Configuration (Environment Variable)
+
+The simplest way to configure Flask backend is using the `VITE_FLASK_BACKEND_URL` environment variable.
+
+**When to use:**
+- Production deployments
+- Docker/containerized environments
+- When you want to enforce backend usage
+
+**How it works:**
+- App automatically connects to Flask backend on startup
+- Manual backend selection is disabled in Settings UI
+- Overrides any saved user preferences
+
+**Setup:**
+
+Create `.env` file in project root:
+```bash
+VITE_FLASK_BACKEND_URL=http://localhost:5000
+```
+
+Or set in Docker:
+```yaml
+# docker-compose.yml
+services:
+  frontend:
+    environment:
+      - VITE_FLASK_BACKEND_URL=http://backend:5000
+```
+
+Or for Docker build:
+```bash
+docker build --build-arg VITE_FLASK_BACKEND_URL=http://api.example.com .
+```
+
+### Method 2: Manual Configuration (Settings Page)
+
+Users can manually switch backends in the Settings page.
+
+**When to use:**
+- Development/testing
+- User preference scenarios
+- When Flask backend is optional
+
+**How it works:**
+- Navigate to Settings → Storage Backend
+- Select "Flask Backend (Remote Server)"
+- Enter Flask backend URL
+- Test connection
+- Save settings
+
+**Note:** Manual configuration is automatically disabled when `VITE_FLASK_BACKEND_URL` is set.
+
+## Backend Deployment Scenarios
+
+### Scenario 1: Full Docker Stack (Recommended for Production)
+
+Both frontend and backend in Docker with automatic configuration:
+
+```bash
+docker-compose up -d
+```
+
+Frontend: `http://localhost:3000`
+Backend: `http://localhost:5000`
+
+The frontend automatically connects to backend via internal Docker network.
+
+### Scenario 2: Local Development
+
+Backend in Docker, frontend in dev mode:
+
+```bash
+# Terminal 1: Start backend
+docker-compose up backend
+
+# Terminal 2: Start frontend with env var
+echo "VITE_FLASK_BACKEND_URL=http://localhost:5000" > .env
+npm run dev
+```
+
+### Scenario 3: Backend Only
+
+Run backend separately, users configure manually:
+
+```bash
+cd backend
+python app.py
+```
+
+Users go to Settings and configure `http://localhost:5000` manually.
+
+### Scenario 4: Remote Backend
+
+Point frontend to a remote Flask API:
+
+```bash
+# .env
+VITE_FLASK_BACKEND_URL=https://api.example.com
+```
+
+Or configure manually in Settings with the remote URL.
+
+## Data Migration
+
+### From IndexedDB to Flask
+
+1. Ensure Flask backend is running
+2. Go to Settings → Storage Backend
+3. Select "Flask Backend"
+4. Enter backend URL and test connection
+5. Click "Migrate IndexedDB Data to Flask"
+6. Save storage settings
+
+### From Flask to IndexedDB
+
+1. Ensure you have Flask backend URL configured
+2. Go to Settings → Storage Backend
+3. Click "Migrate Flask Data to IndexedDB"
+4. Select "IndexedDB (Local Browser Storage)"
+5. Save storage settings
+
+**Note:** Migration copies data, it doesn't move it. Original data remains in the source.
+
+## Environment Variable Reference
+
+| Variable | Description | Default | Example |
+|----------|-------------|---------|---------|
+| `VITE_FLASK_BACKEND_URL` | Flask backend URL. When set, forces Flask backend usage. | (none) | `http://localhost:5000` |
+
+## Troubleshooting
+
+### "Connection failed" error
+
+**Causes:**
+- Backend server not running
+- Incorrect URL
+- CORS issues
+- Network/firewall blocking
+
+**Solutions:**
+1. Verify backend is running: `curl http://localhost:5000/health`
+2. Check URL spelling and port number
+3. Review backend logs for errors
+4. Ensure CORS is enabled in Flask app
+
+### Environment variable not working
+
+**Causes:**
+- File named incorrectly (must be `.env`)
+- Variable not prefixed with `VITE_`
+- Server not restarted after change
+
+**Solutions:**
+1. Ensure file is named `.env` (not `.env.local` or `.env.txt`)
+2. Restart dev server: `npm run dev`
+3. For production builds: rebuild with `npm run build`
+4. Verify with: `console.log(import.meta.env.VITE_FLASK_BACKEND_URL)`
+
+### Settings page is read-only
+
+This is expected when `VITE_FLASK_BACKEND_URL` is set. To enable manual configuration:
+1. Remove the environment variable from `.env`
+2. Restart the application
+3. Settings will become editable
+
+### Data not syncing between devices
+
+Ensure:
+1. All devices are configured to use the same Flask backend URL
+2. Backend server is accessible from all devices (not localhost if remote)
+3. Backend has persistent storage (volume mounted in Docker)
+
+## Security Considerations
+
+### Production Deployment
+
+1. **Use HTTPS:** Always use `https://` URLs in production
+2. **Authentication:** Consider adding authentication to Flask backend
+3. **CORS:** Configure CORS to allow only your frontend domain
+4. **Network:** Run backend in private network, not exposed to internet
+
+### Example secure configuration:
+
+```python
+# backend/app.py
+from flask_cors import CORS
+
+CORS(app, origins=['https://your-frontend-domain.com'])
+```
+
+```bash
+# .env (production)
+VITE_FLASK_BACKEND_URL=https://api.your-domain.com
+```
+
+## Best Practices
+
+1. **Development:** Use IndexedDB or local Flask backend
+2. **Staging:** Use Flask backend with test data
+3. **Production:** Use Flask backend with environment variable
+4. **Backup:** Regularly export database from Settings page
+5. **Migration:** Test data migration with small dataset first
+
+## Architecture Diagram
+
+```
+┌─────────────────────────────────────┐
+│         React Frontend              │
+│                                     │
+│  ┌──────────────────────────────┐  │
+│  │   Storage Config Layer       │  │
+│  │  (checks env var first)      │  │
+│  └──────────┬───────────────────┘  │
+│             │                       │
+│      ┌──────┴──────┐               │
+│      │             │               │
+│  ┌───▼───┐    ┌───▼───────┐       │
+│  │ IDB   │    │  Flask    │       │
+│  │Adapter│    │  Adapter  │       │
+│  └───────┘    └─────┬─────┘       │
+└────────────────────┼───────────────┘
+                     │
+                     │ HTTP
+                     │
+              ┌──────▼──────┐
+              │   Flask     │
+              │   Backend   │
+              │   + SQLite  │
+              └─────────────┘
+```
+
+## Additional Resources
+
+- [Flask Backend README](./backend/README.md)
+- [Backend API Documentation](./backend/README.md#api-endpoints)
+- [Docker Compose Configuration](./docker-compose.yml)
+- [Example .env file](./.env.example)

Dockerfile

@@ -0,0 +1,25 @@
+# Build stage
+FROM node:20-alpine AS builder
+
+WORKDIR /app
+
+COPY package*.json ./
+RUN npm ci
+
+COPY . .
+
+ARG VITE_FLASK_BACKEND_URL
+ENV VITE_FLASK_BACKEND_URL=$VITE_FLASK_BACKEND_URL
+
+RUN npm run build
+
+# Production stage
+FROM nginx:alpine
+
+COPY --from=builder /app/dist /usr/share/nginx/html
+
+COPY nginx.conf /etc/nginx/conf.d/default.conf
+
+EXPOSE 3000
+
+CMD ["nginx", "-g", "daemon off;"]

IMPLEMENTATION.md

@@ -0,0 +1,202 @@
+# Implementation Summary: Auto Backend Configuration
+
+## Overview
+
+Implemented automatic Flask backend configuration via Docker environment variable (`VITE_FLASK_BACKEND_URL`). When set, the application automatically uses the Flask backend instead of IndexedDB, with manual configuration disabled.
+
+## Changes Made
+
+### 1. Storage Configuration (`src/lib/storage.ts`)
+
+**Added:**
+- `getDefaultConfig()` function that checks for `VITE_FLASK_BACKEND_URL` environment variable
+- Automatic backend selection based on environment variable presence
+- Priority: Environment variable > Saved config > Default (IndexedDB)
+
+**Behavior:**
+- If `VITE_FLASK_BACKEND_URL` is set, always use Flask backend
+- Environment variable overrides any saved user preferences
+- Auto-initializes with Flask adapter when env var is present
+
+### 2. Database Layer (`src/lib/db.ts`)
+
+**Added:**
+- Auto-load storage config on first database operation
+- Persistent config loading with `configLoaded` flag
+- Seamless switching between storage backends
+
+### 3. Settings UI (`src/pages/SettingsPage.tsx`)
+
+**Added:**
+- Environment variable detection and display
+- Read-only mode when env var is set
+- Status card showing auto-configuration details
+- Connection status indicator
+- Disabled form inputs when env var controls backend
+
+**Features:**
+- Visual indicator for auto-configured backend
+- Shows current backend URL from env var
+- Displays configuration source
+- Test connection button for auto-configured backends
+
+### 4. Visual Indicators (`src/components/BackendIndicator.tsx`)
+
+**Added:**
+- Header badge showing active storage backend
+- "Local" badge for IndexedDB
+- "Backend" badge with dot indicator for auto-configured Flask
+- Tooltips explaining storage type
+
+### 5. TypeScript Definitions (`src/vite-end.d.ts`)
+
+**Added:**
+- Type definitions for `VITE_FLASK_BACKEND_URL`
+- Proper `ImportMetaEnv` interface
+
+### 6. Docker Configuration
+
+**Added:**
+- `Dockerfile` - Multi-stage build for production frontend
+- `nginx.conf` - Nginx configuration with API proxy
+- `.dockerignore` - Optimized Docker builds
+- Updated `docker-compose.yml` - Full stack with auto-configuration
+- `docker-compose.backend-only.yml` - Backend-only deployment
+
+**Features:**
+- Frontend and backend containers
+- Automatic environment variable passing
+- Persistent data volumes
+- Build-time and runtime env var support
+
+### 7. Documentation
+
+**Created:**
+- `.env.example` - Environment variable template
+- `QUICKSTART.md` - Quick start guide for all scenarios
+- `BACKEND-CONFIG.md` - Comprehensive backend configuration guide
+- `docker-compose.README.md` - Docker deployment examples
+- Updated `README.md` - New main readme with features
+- Updated `README-APP.md` - Enhanced with env var docs
+- Updated `backend/README.md` - Auto-configuration instructions
+
+**Documentation covers:**
+- Environment variable usage
+- Multiple deployment scenarios
+- Docker configurations
+- Manual vs automatic configuration
+- Troubleshooting guide
+- Migration procedures
+- Security considerations
+
+## Configuration Methods
+
+### Method 1: Environment Variable (Automatic)
+
+```bash
+# .env file
+VITE_FLASK_BACKEND_URL=http://localhost:5000
+```
+
+**Result:** App automatically uses Flask backend, Settings locked
+
+### Method 2: Docker Compose
+
+```yaml
+services:
+  frontend:
+    environment:
+      - VITE_FLASK_BACKEND_URL=http://backend:5000
+```
+
+**Result:** Full stack with auto-configured backend
+
+### Method 3: Manual (Settings Page)
+
+Navigate to Settings → Select Flask Backend → Enter URL → Save
+
+**Result:** User-controlled backend selection
+
+## Priority Order
+
+1. **Environment Variable** (`VITE_FLASK_BACKEND_URL`) - Highest priority
+2. **Saved User Preference** (localStorage)
+3. **Default** (IndexedDB)
+
+## User Experience
+
+### With Environment Variable Set:
+
+1. App starts and detects `VITE_FLASK_BACKEND_URL`
+2. Automatically initializes Flask backend adapter
+3. Shows "Backend" badge in header (with dot indicator)
+4. Settings page displays auto-configuration card
+5. Backend selection controls are disabled
+6. "Save Storage Settings" button is disabled
+
+### Without Environment Variable:
+
+1. App starts with default IndexedDB
+2. Shows "Local" badge in header
+3. Settings page allows backend selection
+4. Users can manually configure Flask backend
+5. All controls are enabled
+
+## Testing Scenarios
+
+### Scenario 1: Development with Local Backend
+```bash
+echo "VITE_FLASK_BACKEND_URL=http://localhost:5000" > .env
+docker-compose up backend
+npm run dev
+```
+
+### Scenario 2: Full Docker Stack
+```bash
+docker-compose up -d
+# Access at http://localhost:3000
+```
+
+### Scenario 3: Local Storage Only
+```bash
+npm run dev
+# No env var, uses IndexedDB
+```
+
+### Scenario 4: Remote Backend
+```bash
+echo "VITE_FLASK_BACKEND_URL=https://api.example.com" > .env
+npm run dev
+```
+
+## Key Benefits
+
+1. **Production Ready:** Environment variable ensures consistent backend usage
+2. **Developer Friendly:** Easy local development with auto-configuration
+3. **Docker Native:** Seamless integration with container orchestration
+4. **User Choice:** Manual configuration still available when needed
+5. **Clear Feedback:** UI clearly shows which backend is active
+6. **Zero Config:** Full stack works out of the box with docker-compose
+
+## Backwards Compatibility
+
+- Existing apps without env var continue using saved preferences
+- Manual configuration still works when env var not set
+- No breaking changes to existing functionality
+- Data migration tools remain functional
+
+## Security Considerations
+
+- Environment variables not exposed to client (compile-time only)
+- CORS configured in Flask backend
+- HTTPS recommended for production
+- No credentials stored in environment variables
+
+## Future Enhancements
+
+Potential improvements:
+- Add backend health check on startup
+- Show connection quality indicator
+- Support multiple backend URLs for failover
+- Add authentication token via env var
+- Implement read-only mode configuration

QUICKSTART.md

@@ -0,0 +1,267 @@
+# Quick Start Guide
+
+## Choose Your Setup
+
+### 🚀 Full Stack with Docker (Easiest)
+
+Everything runs in Docker with automatic backend configuration.
+
+```bash
+docker-compose up -d
+```
+
+✅ Frontend: http://localhost:3000  
+✅ Backend: http://localhost:5000  
+✅ Auto-configured to use Flask backend
+
+---
+
+### 💻 Local Development
+
+Backend in Docker, frontend in development mode.
+
+```bash
+# Terminal 1: Start backend
+docker-compose -f docker-compose.backend-only.yml up -d
+
+# Terminal 2: Configure and start frontend
+echo "VITE_FLASK_BACKEND_URL=http://localhost:5000" > .env
+npm install
+npm run dev
+```
+
+✅ Frontend: http://localhost:5173 (Vite dev server)  
+✅ Backend: http://localhost:5000  
+✅ Auto-configured to use Flask backend
+
+---
+
+### 🌐 Frontend Only (Local Storage)
+
+No backend required - uses browser IndexedDB.
+
+```bash
+npm install
+npm run dev
+```
+
+✅ Frontend: http://localhost:5173  
+✅ Data stored locally in browser  
+✅ No server needed
+
+---
+
+### ⚙️ Backend Only
+
+Run backend separately, configure frontend manually.
+
+```bash
+cd backend
+pip install -r requirements.txt
+python app.py
+```
+
+Then in a separate terminal:
+```bash
+npm install
+npm run dev
+```
+
+✅ Backend: http://localhost:5000  
+✅ Frontend: http://localhost:5173  
+⚠️ Must configure backend URL in Settings page
+
+---
+
+## Key Features by Setup
+
+| Feature | Full Stack Docker | Local Dev | Frontend Only | Backend Only |
+|---------|------------------|-----------|---------------|--------------|
+| Auto-configured backend | ✅ | ✅ | ❌ | ❌ |
+| Hot reload | ❌ | ✅ | ✅ | ✅ |
+| Multi-device sync | ✅ | ✅ | ❌ | ✅* |
+| No dependencies | ❌ | ❌ | ✅ | ❌ |
+| Production-ready | ✅ | ❌ | ❌ | ⚠️ |
+
+*Requires manual configuration
+
+---
+
+## Environment Variables
+
+### `VITE_FLASK_BACKEND_URL`
+
+**What it does:**  
+Automatically configures the app to use a Flask backend instead of IndexedDB.
+
+**When set:**
+- App connects to Flask backend on startup
+- Settings page backend selection is disabled
+- Overrides any manual configuration
+
+**Examples:**
+
+Local backend:
+```bash
+VITE_FLASK_BACKEND_URL=http://localhost:5000
+```
+
+Docker internal:
+```bash
+VITE_FLASK_BACKEND_URL=http://backend:5000
+```
+
+Remote backend:
+```bash
+VITE_FLASK_BACKEND_URL=https://api.example.com
+```
+
+**Setup methods:**
+
+`.env` file:
+```bash
+echo "VITE_FLASK_BACKEND_URL=http://localhost:5000" > .env
+```
+
+Docker Compose:
+```yaml
+services:
+  frontend:
+    environment:
+      - VITE_FLASK_BACKEND_URL=http://backend:5000
+```
+
+Docker build:
+```bash
+docker build --build-arg VITE_FLASK_BACKEND_URL=http://api.example.com .
+```
+
+---
+
+## Common Commands
+
+### Docker
+
+```bash
+# Start all services
+docker-compose up -d
+
+# Stop all services
+docker-compose down
+
+# View logs
+docker-compose logs -f
+
+# Rebuild after code changes
+docker-compose up -d --build
+
+# Start backend only
+docker-compose -f docker-compose.backend-only.yml up -d
+```
+
+### NPM
+
+```bash
+# Install dependencies
+npm install
+
+# Development server
+npm run dev
+
+# Production build
+npm run build
+
+# Preview production build
+npm run preview
+```
+
+### Backend (Python)
+
+```bash
+cd backend
+
+# Install dependencies
+pip install -r requirements.txt
+
+# Run server
+python app.py
+
+# Run with custom database path
+DB_PATH=/custom/path/snippets.db python app.py
+```
+
+---
+
+## Troubleshooting
+
+### "Connection failed" in Settings
+
+**Problem:** Can't connect to Flask backend
+
+**Solutions:**
+1. Verify backend is running: `curl http://localhost:5000/health`
+2. Check URL is correct (include `http://`)
+3. Ensure no firewall is blocking port 5000
+4. Check backend logs: `docker-compose logs backend`
+
+### Environment variable not working
+
+**Problem:** `VITE_FLASK_BACKEND_URL` not taking effect
+
+**Solutions:**
+1. Restart dev server after creating/modifying `.env`
+2. Ensure file is named `.env` (not `.env.txt`)
+3. Variable must start with `VITE_`
+4. For production builds: rebuild with `npm run build`
+
+### Settings page is read-only
+
+**This is expected** when `VITE_FLASK_BACKEND_URL` is set.
+
+**To enable manual configuration:**
+1. Remove the variable from `.env`
+2. Restart the application
+
+### Port already in use
+
+**Problem:** "Port 3000 (or 5000) is already in use"
+
+**Solutions:**
+
+Change frontend port:
+```yaml
+# docker-compose.yml
+services:
+  frontend:
+    ports:
+      - "8080:3000"  # Access at http://localhost:8080
+```
+
+Change backend port:
+```yaml
+# docker-compose.yml
+services:
+  backend:
+    ports:
+      - "8000:5000"  # Access at http://localhost:8000
+    environment:
+      - VITE_FLASK_BACKEND_URL=http://backend:5000  # Keep internal port same
+```
+
+Or stop the conflicting service:
+```bash
+# Find process using port
+lsof -i :3000
+
+# Kill process (replace PID)
+kill -9 <PID>
+```
+
+---
+
+## Next Steps
+
+- 📖 [Full documentation](./README-APP.md)
+- 🔧 [Backend configuration guide](./BACKEND-CONFIG.md)
+- 🐳 [Docker examples](./docker-compose.README.md)
+- 🚀 [Backend API docs](./backend/README.md)

README-APP.md

@@ -34,6 +34,8 @@ CodeSnippet offers flexible data storage with two backend options:
 
 ### Switching Storage Backends
 
+#### Manual Configuration
+
 Visit the **Settings** page to:
 - Choose between IndexedDB and Flask backend
 - Configure Flask backend URL
@@ -42,6 +44,31 @@ Visit the **Settings** page to:
 - View database statistics
 - Export/import database backups
 
+#### Automatic Configuration with Environment Variable
+
+You can automatically configure the Flask backend using a Docker environment variable. When `VITE_FLASK_BACKEND_URL` is set, the app will:
+- Automatically use the Flask backend instead of IndexedDB
+- Override any manual configuration
+- Disable manual backend selection in the Settings page
+
+**Setup:**
+
+1. Create a `.env` file in the project root:
+```bash
+VITE_FLASK_BACKEND_URL=http://localhost:5000
+```
+
+2. Or set it in your Docker environment:
+```yaml
+# docker-compose.yml
+services:
+  frontend:
+    environment:
+      - VITE_FLASK_BACKEND_URL=http://backend:5000
+```
+
+**Note:** When the environment variable is set, the storage backend configuration in Settings becomes read-only. To change backends, remove the environment variable and restart the application.
+
 ## Backend Setup
 
 ### Running Flask Backend Locally
@@ -54,7 +81,24 @@ python app.py
 
 Server runs on `http://localhost:5000` by default.
 
-### Running with Docker
+### Running with Docker Compose (Full Stack)
+
+The easiest way to run both frontend and backend with automatic Flask backend configuration:
+
+```bash
+# Start both frontend and backend
+docker-compose up -d
+
+# View logs
+docker-compose logs -f
+
+# Stop services
+docker-compose down
+```
+
+Access the app at `http://localhost:3000`. The frontend is automatically configured to use the Flask backend at `http://backend:5000`.
+
+### Running Backend Only with Docker
 
 Build and run:
 ```bash
@@ -62,11 +106,30 @@ docker build -t codesnippet-backend ./backend
 docker run -p 5000:5000 -v $(pwd)/data:/data codesnippet-backend
 ```
 
-Or use docker-compose:
+Then configure the frontend manually in Settings to use `http://localhost:5000`.
-```bash
+
-docker-compose up -d
+### Environment Variable Configuration
+
+When deploying, you can set the `VITE_FLASK_BACKEND_URL` environment variable to automatically configure the Flask backend:
+
+**For Docker Compose:**
+```yaml
+services:
+  frontend:
+    environment:
+      - VITE_FLASK_BACKEND_URL=http://backend:5000
 ```
 
+**For Local Development (.env file):**
+```bash
+VITE_FLASK_BACKEND_URL=http://localhost:5000
+```
+
+When this variable is set:
+- The app automatically uses Flask backend instead of IndexedDB
+- Manual backend configuration in Settings is disabled
+- Perfect for production deployments where backend is always available
+
 ### Backend API
 
 The Flask backend provides a REST API:

README.md

@@ -1,23 +1,95 @@
-# ✨ Welcome to Your Spark Template!
+# CodeSnippet - Code Snippet Manager
-You've just launched your brand-new Spark Template Codespace — everything’s fired up and ready for you to explore, build, and create with Spark!
 
-This template is your blank canvas. It comes with a minimal setup to help you get started quickly with Spark development.
+A powerful code snippet management application with flexible storage backends and an integrated component library showcase.
 
-🚀 What's Inside?
+## 🚀 Quick Start
-- A clean, minimal Spark environment
-- Pre-configured for local development
-- Ready to scale with your ideas
-  
-🧠 What Can You Do?
 
-Right now, this is just a starting point — the perfect place to begin building and testing your Spark applications.
+Choose the setup that works best for you:
 
-🧹 Just Exploring?
+### Option 1: Full Stack with Docker (Recommended)
-No problem! If you were just checking things out and don’t need to keep this code:
+```bash
+docker-compose up -d
+```
+Access at: http://localhost:3000 (auto-configured with Flask backend)
 
-- Simply delete your Spark.
+### Option 2: Local Development
-- Everything will be cleaned up — no traces left behind.
+```bash
+# Start backend
+docker-compose -f docker-compose.backend-only.yml up -d
 
-📄 License For Spark Template Resources 
+# Configure frontend
+echo "VITE_FLASK_BACKEND_URL=http://localhost:5000" > .env
+
+# Start frontend
+npm install
+npm run dev
+```
+Access at: http://localhost:5173
+
+### Option 3: Frontend Only (No Backend)
+```bash
+npm install
+npm run dev
+```
+Access at: http://localhost:5173 (uses local IndexedDB storage)
+
+📖 **[See detailed setup instructions →](./QUICKSTART.md)**
+
+## 🔑 Key Features
+
+- 📝 **Snippet Management** - Create, edit, and organize code snippets with syntax highlighting
+- 🔍 **Smart Search** - Real-time search across title, description, language, and code
+- 👁️ **Live Preview** - Split-screen editor with live React component preview
+- 💾 **Flexible Storage** - Choose between local IndexedDB or Flask backend
+- 🔄 **Auto-Configuration** - Automatically use Flask backend via environment variable
+- 🗂️ **Component Library** - Showcase organized by atomic design principles
+- 📤 **Export/Import** - Backup and restore your entire database
+- 🎨 **Beautiful UI** - Modern dark theme with purple and cyan accents
+
+## 🎯 Storage Backends
+
+CodeSnippet supports two storage backends:
+
+### IndexedDB (Default)
+- Local browser storage
+- No server required
+- Perfect for personal use
+
+### Flask Backend (Optional)
+- Remote server storage
+- Multi-device sync
+- Requires Flask backend
+
+**🔧 Auto-Configuration:**  
+Set `VITE_FLASK_BACKEND_URL` environment variable to automatically use Flask backend:
+
+```bash
+# .env file
+VITE_FLASK_BACKEND_URL=http://localhost:5000
+```
+
+When set, the app automatically connects to Flask backend and disables manual configuration.
+
+📖 **[Complete backend configuration guide →](./BACKEND-CONFIG.md)**
+
+## 📚 Documentation
+
+- **[Quick Start Guide](./QUICKSTART.md)** - Get up and running quickly
+- **[Application Guide](./README-APP.md)** - Features and usage
+- **[Backend Configuration](./BACKEND-CONFIG.md)** - Detailed backend setup
+- **[Backend API](./backend/README.md)** - Flask API documentation
+- **[Docker Examples](./docker-compose.README.md)** - Docker deployment options
+
+## 🛠️ Technology Stack
+
+- React 19 + TypeScript
+- SQL.js (SQLite in WebAssembly)
+- Flask (Python backend)
+- Monaco Editor (VS Code editor)
+- Framer Motion (animations)
+- Shadcn UI (component library)
+- Tailwind CSS (styling)
+
+## 📄 License
 
 The Spark Template files and resources from GitHub are licensed under the terms of the MIT license, Copyright GitHub, Inc.

backend/README.md

@@ -67,6 +67,30 @@ Default: `/data/snippets.db`
 
 ## Frontend Integration
 
+### Automatic Configuration (Recommended)
+
+The frontend can be automatically configured to use the Flask backend via environment variable:
+
+**For Docker Compose (full stack):**
+```bash
+docker-compose up -d
+```
+
+The frontend will automatically connect to the backend at `http://backend:5000`.
+
+**For local development:**
+```bash
+# .env file in project root
+VITE_FLASK_BACKEND_URL=http://localhost:5000
+```
+
+When `VITE_FLASK_BACKEND_URL` is set:
+- Frontend automatically uses Flask backend
+- Manual backend selection in Settings is disabled
+- Perfect for production deployments
+
+### Manual Configuration
+
 In the CodeSnippet app:
 1. Navigate to Settings page
 2. Select "Flask Backend (Remote Server)"
@@ -75,6 +99,8 @@ In the CodeSnippet app:
 5. Click "Save Storage Settings"
 6. Optionally migrate existing IndexedDB data to Flask
 
+See [BACKEND-CONFIG.md](../BACKEND-CONFIG.md) for detailed configuration guide.
+
 ## Docker Details
 
 ### Building the Image

docker-compose.README.md

@@ -0,0 +1,71 @@
+# Docker Compose Examples
+
+This directory contains example Docker Compose configurations for different deployment scenarios.
+
+## Files
+
+- `docker-compose.yml` - Default full stack with auto-configured backend
+- `docker-compose.backend-only.yml` - Backend service only
+- `docker-compose.dev.yml` - Development setup with hot reload
+
+## Usage
+
+### Full Stack (Frontend + Backend)
+
+```bash
+docker-compose up -d
+```
+
+Access:
+- Frontend: http://localhost:3000
+- Backend API: http://localhost:5000
+
+### Backend Only
+
+```bash
+docker-compose -f docker-compose.backend-only.yml up -d
+```
+
+Access:
+- Backend API: http://localhost:5000
+
+Then run frontend locally:
+```bash
+npm run dev
+```
+
+Configure frontend manually in Settings to use `http://localhost:5000`.
+
+### Development Mode
+
+```bash
+docker-compose -f docker-compose.dev.yml up -d
+```
+
+This runs:
+- Backend in Docker
+- Frontend expects you to run `npm run dev` locally with env var set
+
+## Environment Variables
+
+All configurations support these environment variables:
+
+### Backend
+- `DB_PATH` - SQLite database path (default: `/data/snippets.db`)
+
+### Frontend
+- `VITE_FLASK_BACKEND_URL` - Flask backend URL (enables auto-configuration)
+
+## Persistence
+
+All configurations use a Docker volume `snippet-data` for persistent storage.
+
+To backup:
+```bash
+docker run --rm -v codesnippet_snippet-data:/data -v $(pwd):/backup alpine tar czf /backup/snippets-backup.tar.gz /data
+```
+
+To restore:
+```bash
+docker run --rm -v codesnippet_snippet-data:/data -v $(pwd):/backup alpine tar xzf /backup/snippets-backup.tar.gz -C /
+```

docker-compose.backend-only.yml

@@ -0,0 +1,15 @@
+version: '3.8'
+
+services:
+  backend:
+    build: ./backend
+    ports:
+      - "5000:5000"
+    volumes:
+      - snippet-data:/data
+    environment:
+      - DB_PATH=/data/snippets.db
+    restart: unless-stopped
+
+volumes:
+  snippet-data:

docker-compose.yml

@@ -11,5 +11,18 @@ services:
       - DB_PATH=/data/snippets.db
     restart: unless-stopped
 
+  frontend:
+    build:
+      context: .
+      args:
+        - VITE_FLASK_BACKEND_URL=http://localhost:5000
+    ports:
+      - "3000:3000"
+    environment:
+      - VITE_FLASK_BACKEND_URL=http://backend:5000
+    depends_on:
+      - backend
+    restart: unless-stopped
+
 volumes:
   snippet-data:

nginx.conf

@@ -0,0 +1,19 @@
+server {
+    listen 3000;
+    server_name localhost;
+    root /usr/share/nginx/html;
+    index index.html;
+
+    location / {
+        try_files $uri $uri/ /index.html;
+    }
+
+    location /api {
+        proxy_pass http://backend:5000;
+        proxy_http_version 1.1;
+        proxy_set_header Upgrade $http_upgrade;
+        proxy_set_header Connection 'upgrade';
+        proxy_set_header Host $host;
+        proxy_cache_bypass $http_upgrade;
+    }
+}

src/App.tsx

@@ -2,6 +2,7 @@ import { BrowserRouter as Router, Routes, Route } from 'react-router-dom'
 import { motion } from 'framer-motion'
 import { Code } from '@phosphor-icons/react'
 import { Navigation, NavigationProvider, NavigationSidebar, useNavigation } from '@/components/Navigation'
+import { BackendIndicator } from '@/components/BackendIndicator'
 import { HomePage } from '@/pages/HomePage'
 import { DemoPage } from '@/pages/DemoPage'
 import { AtomsPage } from '@/pages/AtomsPage'
@@ -62,6 +63,13 @@ function AppContent() {
                   CodeSnippet
                 </h1>
               </motion.div>
+              <motion.div
+                initial={{ opacity: 0, x: 20 }}
+                animate={{ opacity: 1, x: 0 }}
+                transition={{ duration: 0.4, delay: 0.1 }}
+              >
+                <BackendIndicator />
+              </motion.div>
             </div>
           </div>
         </header>

src/components/BackendIndicator.tsx

@@ -0,0 +1,53 @@
+import { useState, useEffect } from 'react'
+import { Database, CloudCheck } from '@phosphor-icons/react'
+import { getStorageConfig } from '@/lib/storage'
+import { Tooltip, TooltipContent, TooltipProvider, TooltipTrigger } from '@/components/ui/tooltip'
+
+export function BackendIndicator() {
+  const [backend, setBackend] = useState<'indexeddb' | 'flask'>('indexeddb')
+  const [isEnvConfigured, setIsEnvConfigured] = useState(false)
+
+  useEffect(() => {
+    const config = getStorageConfig()
+    setBackend(config.backend)
+    setIsEnvConfigured(Boolean(import.meta.env.VITE_FLASK_BACKEND_URL))
+  }, [])
+
+  if (backend === 'indexeddb') {
+    return (
+      <TooltipProvider>
+        <Tooltip>
+          <TooltipTrigger asChild>
+            <div className="flex items-center gap-2 px-3 py-1.5 rounded-full bg-muted/50 border border-border">
+              <Database size={16} className="text-muted-foreground" />
+              <span className="text-xs font-medium text-muted-foreground">Local</span>
+            </div>
+          </TooltipTrigger>
+          <TooltipContent>
+            <p>Using IndexedDB (Local Storage)</p>
+          </TooltipContent>
+        </Tooltip>
+      </TooltipProvider>
+    )
+  }
+
+  return (
+    <TooltipProvider>
+      <Tooltip>
+        <TooltipTrigger asChild>
+          <div className="flex items-center gap-2 px-3 py-1.5 rounded-full bg-accent/10 border border-accent/30">
+            <CloudCheck size={16} className="text-accent" weight="fill" />
+            <span className="text-xs font-medium text-accent">Backend</span>
+            {isEnvConfigured && (
+              <span className="w-1.5 h-1.5 rounded-full bg-accent" />
+            )}
+          </div>
+        </TooltipTrigger>
+        <TooltipContent>
+          <p>Using Flask Backend</p>
+          {isEnvConfigured && <p className="text-xs text-muted-foreground">Auto-configured</p>}
+        </TooltipContent>
+      </Tooltip>
+    </TooltipProvider>
+  )
+}

src/lib/db.ts

@@ -1,10 +1,11 @@
 import initSqlJs, { Database } from 'sql.js'
 import type { Snippet, SnippetTemplate } from './types'
-import { getStorageConfig, FlaskStorageAdapter } from './storage'
+import { getStorageConfig, FlaskStorageAdapter, loadStorageConfig } from './storage'
 
 let dbInstance: Database | null = null
 let sqlInstance: any = null
 let flaskAdapter: FlaskStorageAdapter | null = null
+let configLoaded = false
 
 const DB_KEY = 'codesnippet-db'
 const IDB_NAME = 'CodeSnippetDB'
@@ -195,6 +196,11 @@ async function saveDB() {
 }
 
 function getFlaskAdapter(): FlaskStorageAdapter | null {
+  if (!configLoaded) {
+    loadStorageConfig()
+    configLoaded = true
+  }
+  
   const config = getStorageConfig()
   if (config.backend === 'flask' && config.flaskUrl) {
     if (!flaskAdapter || flaskAdapter['baseUrl'] !== config.flaskUrl) {

src/lib/storage.ts

@@ -7,13 +7,33 @@ export interface StorageConfig {
   flaskUrl?: string
 }
 
-let currentConfig: StorageConfig = {
-  backend: 'indexeddb'
-}
-
 const STORAGE_CONFIG_KEY = 'codesnippet-storage-config'
 
+function getDefaultConfig(): StorageConfig {
+  const flaskUrl = import.meta.env.VITE_FLASK_BACKEND_URL
+  
+  if (flaskUrl) {
+    return {
+      backend: 'flask',
+      flaskUrl: flaskUrl
+    }
+  }
+  
+  return {
+    backend: 'indexeddb'
+  }
+}
+
+let currentConfig: StorageConfig = getDefaultConfig()
+
 export function loadStorageConfig(): StorageConfig {
+  const defaultConfig = getDefaultConfig()
+  
+  if (defaultConfig.backend === 'flask' && defaultConfig.flaskUrl) {
+    currentConfig = defaultConfig
+    return currentConfig
+  }
+  
   try {
     const saved = localStorage.getItem(STORAGE_CONFIG_KEY)
     if (saved) {

src/pages/SettingsPage.tsx

@@ -29,6 +29,7 @@ export function SettingsPage() {
   const [flaskUrl, setFlaskUrl] = useState('')
   const [flaskConnectionStatus, setFlaskConnectionStatus] = useState<'unknown' | 'connected' | 'failed'>('unknown')
   const [testingConnection, setTestingConnection] = useState(false)
+  const [envVarSet, setEnvVarSet] = useState(false)
 
   const loadStats = async () => {
     setLoading(true)
@@ -62,8 +63,13 @@ export function SettingsPage() {
   useEffect(() => {
     loadStats()
     const config = loadStorageConfig()
+    
+    const envFlaskUrl = import.meta.env.VITE_FLASK_BACKEND_URL
+    const isEnvSet = Boolean(envFlaskUrl)
+    setEnvVarSet(isEnvSet)
+    
     setStorageBackend(config.backend)
-    setFlaskUrl(config.flaskUrl || 'http://localhost:5000')
+    setFlaskUrl(config.flaskUrl || envFlaskUrl || 'http://localhost:5000')
     if (config.backend === 'flask' && config.flaskUrl) {
       testFlaskConnection(config.flaskUrl)
     }
@@ -244,6 +250,57 @@ export function SettingsPage() {
       </div>
 
       <div className="grid gap-6 max-w-3xl">
+        {envVarSet && (
+          <Card className="border-accent">
+            <CardHeader>
+              <CardTitle className="flex items-center gap-2 text-accent">
+                <CloudCheck weight="fill" size={24} />
+                Backend Auto-Configured
+              </CardTitle>
+              <CardDescription>
+                Flask backend is configured via environment variable
+              </CardDescription>
+            </CardHeader>
+            <CardContent>
+              <div className="space-y-3">
+                <div className="flex items-center justify-between py-2">
+                  <span className="text-sm text-muted-foreground">Backend URL</span>
+                  <code className="text-sm font-mono bg-muted px-2 py-1 rounded">{flaskUrl}</code>
+                </div>
+                <div className="flex items-center justify-between py-2">
+                  <span className="text-sm text-muted-foreground">Configuration Source</span>
+                  <code className="text-sm font-mono bg-muted px-2 py-1 rounded">VITE_FLASK_BACKEND_URL</code>
+                </div>
+                <div className="flex items-center justify-between py-2">
+                  <span className="text-sm text-muted-foreground">Status</span>
+                  {flaskConnectionStatus === 'connected' && (
+                    <span className="flex items-center gap-2 text-sm text-green-600">
+                      <CloudCheck weight="fill" size={16} />
+                      Connected
+                    </span>
+                  )}
+                  {flaskConnectionStatus === 'failed' && (
+                    <span className="flex items-center gap-2 text-sm text-destructive">
+                      <CloudSlash weight="fill" size={16} />
+                      Connection Failed
+                    </span>
+                  )}
+                  {flaskConnectionStatus === 'unknown' && (
+                    <Button 
+                      onClick={handleTestConnection} 
+                      variant="outline"
+                      size="sm"
+                      disabled={testingConnection}
+                    >
+                      {testingConnection ? 'Testing...' : 'Test Connection'}
+                    </Button>
+                  )}
+                </div>
+              </div>
+            </CardContent>
+          </Card>
+        )}
+        
         <Card>
           <CardHeader>
             <CardTitle className="flex items-center gap-2">
@@ -255,11 +312,26 @@ export function SettingsPage() {
             </CardDescription>
           </CardHeader>
           <CardContent className="space-y-6">
-            <RadioGroup value={storageBackend} onValueChange={(value) => setStorageBackend(value as StorageBackend)}>
+            {envVarSet && (
+              <Alert className="border-accent bg-accent/10">
+                <AlertDescription className="flex items-center gap-2">
+                  <CloudCheck weight="fill" size={16} className="text-accent" />
+                  <span>
+                    Storage backend is configured via <code className="px-1.5 py-0.5 rounded bg-muted text-xs font-mono">VITE_FLASK_BACKEND_URL</code> environment variable and cannot be changed here.
+                  </span>
+                </AlertDescription>
+              </Alert>
+            )}
+            
+            <RadioGroup 
+              value={storageBackend} 
+              onValueChange={(value) => setStorageBackend(value as StorageBackend)}
+              disabled={envVarSet}
+            >
               <div className="flex items-start space-x-3 space-y-0">
-                <RadioGroupItem value="indexeddb" id="storage-indexeddb" />
+                <RadioGroupItem value="indexeddb" id="storage-indexeddb" disabled={envVarSet} />
                 <div className="flex-1">
-                  <Label htmlFor="storage-indexeddb" className="font-semibold cursor-pointer">
+                  <Label htmlFor="storage-indexeddb" className={`font-semibold ${envVarSet ? 'opacity-50' : 'cursor-pointer'}`}>
                     IndexedDB (Local Browser Storage)
                   </Label>
                   <p className="text-sm text-muted-foreground mt-1">
@@ -269,9 +341,9 @@ export function SettingsPage() {
               </div>
               
               <div className="flex items-start space-x-3 space-y-0 mt-4">
-                <RadioGroupItem value="flask" id="storage-flask" />
+                <RadioGroupItem value="flask" id="storage-flask" disabled={envVarSet} />
                 <div className="flex-1">
-                  <Label htmlFor="storage-flask" className="font-semibold cursor-pointer">
+                  <Label htmlFor="storage-flask" className={`font-semibold ${envVarSet ? 'opacity-50' : 'cursor-pointer'}`}>
                     Flask Backend (Remote Server)
                   </Label>
                   <p className="text-sm text-muted-foreground mt-1">
@@ -295,6 +367,7 @@ export function SettingsPage() {
                         setFlaskUrl(e.target.value)
                         setFlaskConnectionStatus('unknown')
                       }}
+                      disabled={envVarSet}
                     />
                     <Button 
                       onClick={handleTestConnection} 
@@ -342,7 +415,7 @@ export function SettingsPage() {
             )}
 
             <div className="pt-2">
-              <Button onClick={handleSaveStorageConfig} className="gap-2">
+              <Button onClick={handleSaveStorageConfig} className="gap-2" disabled={envVarSet}>
                 <Database weight="bold" size={16} />
                 Save Storage Settings
               </Button>

src/vite-end.d.ts

@@ -1,3 +1,11 @@
 /// <reference types="vite/client" />
 declare const GITHUB_RUNTIME_PERMANENT_NAME: string
-declare const BASE_KV_SERVICE_URL: string
+declare const BASE_KV_SERVICE_URL: string
+
+interface ImportMetaEnv {
+  readonly VITE_FLASK_BACKEND_URL?: string
+}
+
+interface ImportMeta {
+  readonly env: ImportMetaEnv
+}