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+---
+description: 
+globs: 
+alwaysApply: true
+---
+# TimeSafari Cross-Platform Architecture Guide
+
+## 1. Platform Support Matrix
+
+| Feature | Web (PWA) | Capacitor (Mobile) | Electron (Desktop) | PyWebView (Desktop) |
+|---------|-----------|-------------------|-------------------|-------------------|
+| QR Code Scanning | vue-qrcode-reader | @capacitor-mlkit/barcode-scanning | Not Implemented | Not Implemented |
+| Deep Linking | URL Parameters | App URL Open Events | Not Implemented | Not Implemented |
+| File System | Limited (Browser API) | Capacitor Filesystem | Electron fs | PyWebView Python Bridge |
+| Camera Access | MediaDevices API | Capacitor Camera | Not Implemented | Not Implemented |
+| Platform Detection | Web APIs | Capacitor.isNativePlatform() | process.env checks | process.env checks |
+
+## 2. Build Configuration Structure
+
+### 2.1 Entry Points
+```
+src/
+├── main.ts              # Base entry
+├── main.common.ts       # Shared initialization
+├── main.capacitor.ts    # Mobile entry
+├── main.electron.ts     # Electron entry
+├── main.pywebview.ts    # PyWebView entry
+└── main.web.ts          # Web/PWA entry
+```
+
+### 2.2 Build Configurations
+```
+root/
+├── vite.config.common.mts    # Shared config
+├── vite.config.capacitor.mts # Mobile build
+├── vite.config.electron.mts  # Electron build
+├── vite.config.pywebview.mts # PyWebView build
+└── vite.config.web.mts      # Web/PWA build
+```
+
+## 3. Platform Service Architecture
+
+### 3.1 Service Factory Pattern
+```typescript
+// PlatformServiceFactory.ts
+export class PlatformServiceFactory {
+  private static instance: PlatformService | null = null;
+
+  public static getInstance(): PlatformService {
+    if (!PlatformServiceFactory.instance) {
+      const platform = process.env.VITE_PLATFORM || "web";
+      PlatformServiceFactory.instance = createPlatformService(platform);
+    }
+    return PlatformServiceFactory.instance;
+  }
+}
+```
+
+### 3.2 Platform-Specific Implementations
+```
+services/platforms/
+├── WebPlatformService.ts
+├── CapacitorPlatformService.ts
+├── ElectronPlatformService.ts
+└── PyWebViewPlatformService.ts
+```
+
+## 4. Feature Implementation Guidelines
+
+### 4.1 QR Code Scanning
+
+1. **Factory Pattern**
+```typescript
+export class QRScannerFactory {
+  static getInstance(): QRScannerService {
+    if (__IS_MOBILE__ || Capacitor.isNativePlatform()) {
+      return new CapacitorQRScanner();
+    } else if (__USE_QR_READER__) {
+      return new WebDialogQRScanner();
+    }
+    throw new Error("No QR scanner implementation available");
+  }
+}
+```
+
+2. **Platform-Specific Implementation**
+```typescript
+// Example for Capacitor
+export class CapacitorQRScanner implements QRScannerService {
+  async startScan(options?: QRScannerOptions): Promise<void> {
+    // Platform-specific implementation
+  }
+}
+```
+
+### 4.2 Deep Linking
+
+1. **URL Structure**
+```typescript
+// Format: timesafari://<route>[/<param>][?queryParam1=value1]
+interface DeepLinkParams {
+  route: string;
+  params?: Record<string, string>;
+  query?: Record<string, string>;
+}
+```
+
+2. **Platform Handlers**
+```typescript
+// Capacitor
+App.addListener("appUrlOpen", handleDeepLink);
+
+// Web
+router.beforeEach((to, from, next) => {
+  handleWebDeepLink(to.query);
+});
+```
+
+## 5. Build Process
+
+### 5.1 Environment Configuration
+```typescript
+// vite.config.common.mts
+export function createBuildConfig(mode: string) {
+  return {
+    define: {
+      'process.env.VITE_PLATFORM': JSON.stringify(mode),
+      'process.env.VITE_PWA_ENABLED': JSON.stringify(!isNative),
+      __IS_MOBILE__: JSON.stringify(isCapacitor),
+      __USE_QR_READER__: JSON.stringify(!isCapacitor)
+    }
+  };
+}
+```
+
+### 5.2 Platform-Specific Builds
+
+```bash
+# Build commands from package.json
+"build:web": "vite build --config vite.config.web.mts",
+"build:capacitor": "vite build --config vite.config.capacitor.mts",
+"build:electron": "vite build --config vite.config.electron.mts",
+"build:pywebview": "vite build --config vite.config.pywebview.mts"
+```
+
+## 6. Testing Strategy
+
+### 6.1 Test Configuration
+```typescript
+// playwright.config-local.ts
+const config: PlaywrightTestConfig = {
+  projects: [
+    {
+      name: 'web',
+      use: { browserName: 'chromium' }
+    },
+    {
+      name: 'mobile',
+      use: { ...devices['Pixel 5'] }
+    }
+  ]
+};
+```
+
+### 6.2 Platform-Specific Tests
+```typescript
+test('QR scanning works on mobile', async ({ page }) => {
+  test.skip(!process.env.MOBILE_TEST, 'Mobile-only test');
+  // Test implementation
+});
+```
+
+## 7. Error Handling
+
+### 7.1 Global Error Handler
+```typescript
+function setupGlobalErrorHandler(app: VueApp) {
+  app.config.errorHandler = (err, instance, info) => {
+    logger.error("[App Error]", {
+      error: err,
+      info,
+      component: instance?.$options.name
+    });
+  };
+}
+```
+
+### 7.2 Platform-Specific Error Handling
+```typescript
+// API error handling for Capacitor
+if (process.env.VITE_PLATFORM === 'capacitor') {
+  logger.error(`[Capacitor API Error] ${endpoint}:`, {
+    message: error.message,
+    status: error.response?.status
+  });
+}
+```
+
+## 8. Best Practices
+
+### 8.1 Code Organization
+- Use platform-specific directories for unique implementations
+- Share common code through service interfaces
+- Implement feature detection before using platform capabilities
+
+### 8.2 Platform Detection
+```typescript
+const platformService = PlatformServiceFactory.getInstance();
+const capabilities = platformService.getCapabilities();
+
+if (capabilities.hasCamera) {
+  // Implement camera features
+}
+```
+
+### 8.3 Feature Implementation
+1. Define platform-agnostic interface
+2. Create platform-specific implementations
+3. Use factory pattern for instantiation
+4. Implement graceful fallbacks
+5. Add comprehensive error handling
+
+## 9. Dependency Management
+
+### 9.1 Platform-Specific Dependencies
+```json
+{
+  "dependencies": {
+    "@capacitor/core": "^6.2.0",
+    "electron": "^33.2.1",
+    "vue-qrcode-reader": "^5.5.3"
+  }
+}
+```
+
+### 9.2 Conditional Loading
+```typescript
+if (process.env.VITE_PLATFORM === 'capacitor') {
+  await import('@capacitor/core');
+}
+```
+
+## 10. Security Considerations
+
+### 10.1 Permission Handling
+```typescript
+async checkPermissions(): Promise<boolean> {
+  if (platformService.isCapacitor()) {
+    return await checkNativePermissions();
+  }
+  return await checkWebPermissions();
+}
+```
+
+### 10.2 Data Storage
+- Use platform-appropriate storage mechanisms
+- Implement encryption for sensitive data
+- Handle permissions appropriately
+
+This document should be updated as new features are added or platform-specific implementations change. Regular reviews ensure it remains current with the codebase.