Complete comprehensive code improvement implementation

Co-authored-by: 0xrinegade <[email protected]>

Author: Copilot

docs/ERROR_HANDLING.md

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+# SVMSeek Error Handling and Recovery System
+
+This document describes the comprehensive error handling mechanisms implemented in SVMSeek and how applications should consume error recovery events.
+
+## Overview
+
+SVMSeek implements a multi-layered error handling system designed to:
+1. **Prevent crashes** from third-party wallet extension conflicts
+2. **Recover gracefully** from null pointer access errors
+3. **Provide user-friendly feedback** for recoverable errors
+4. **Maintain application stability** in complex browser environments
+
+## Architecture
+
+### Global Error Handler (`src/utils/globalErrorHandler.ts`)
+
+The `GlobalErrorHandler` class provides comprehensive error catching and recovery:
+
+```typescript
+import { globalErrorHandler } from './utils/globalErrorHandler';
+
+// The handler auto-initializes, but you can access error stats
+const errorStats = globalErrorHandler.getErrorStats();
+console.log('Error statistics:', errorStats);
+```
+
+### Error Types Handled
+
+#### 1. Wallet Extension Conflicts
+- **Problem**: Multiple wallet extensions try to define `window.ethereum`
+- **Solution**: Monkey-patch `Object.defineProperty` to detect and resolve conflicts
+- **Event**: `svmseek-wallet-conflict`
+
+#### 2. Null Property Access
+- **Problem**: Third-party code assumes `event.data` is always defined
+- **Solution**: Wrap event listeners with null-safe validation
+- **Event**: `svmseek-error-recovery`
+
+#### 3. Unhandled Promise Rejections
+- **Problem**: Async operations fail without proper error handling
+- **Solution**: Global promise rejection handler with recovery attempts
+- **Event**: `svmseek-error-recovery`
+
+## Event-Driven Error Recovery
+
+The error handling system dispatches custom events that your application can listen for:
+
+### 1. Error Recovery Events (`svmseek-error-recovery`)
+
+```typescript
+window.addEventListener('svmseek-error-recovery', (event) => {
+  const { errorMessage, errorType, errorCount } = event.detail;
+  
+  // Show user-friendly error message
+  showErrorToast(`Recovered from ${errorType}: ${errorMessage}`);
+  
+  // Track error for analytics
+  analytics.track('error_recovered', {
+    type: errorType,
+    message: errorMessage,
+    count: errorCount
+  });
+  
+  // Attempt specific recovery actions
+  switch (errorType) {
+    case 'promise_rejection':
+      // Retry failed operation
+      retryLastOperation();
+      break;
+    case 'global_error':
+      // Refresh component state
+      refreshApplicationState();
+      break;
+  }
+});
+```
+
+### 2. Wallet Conflict Events (`svmseek-wallet-conflict`)
+
+```typescript
+window.addEventListener('svmseek-wallet-conflict', (event) => {
+  const { message, suggestion } = event.detail;
+  
+  // Show user guidance for wallet conflicts
+  showWalletConflictDialog({
+    title: 'Multiple Wallets Detected',
+    message: message,
+    suggestion: suggestion,
+    actions: [
+      {
+        label: 'Learn More',
+        action: () => openWalletCompatibilityGuide()
+      },
+      {
+        label: 'Continue Anyway',
+        action: () => dismissWalletConflictDialog()
+      }
+    ]
+  });
+});
+```
+
+### 3. Custom SVMSeek Events (`svmseek-event`)
+
+```typescript
+window.addEventListener('svmseek-event', (event) => {
+  const eventData = event.detail;
+  
+  // Handle application-specific events
+  switch (eventData.type) {
+    case 'wallet_injection_ready':
+      console.log('Wallet providers injected successfully');
+      break;
+    case 'security_violation':
+      handleSecurityViolation(eventData);
+      break;
+  }
+});
+```
+
+## Implementation Guidelines
+
+### For Component Developers
+
+#### 1. Defensive Programming
+Always assume external data might be null or undefined:
+
+```typescript
+// ❌ Bad: Assumes event.data exists
+const handleMessage = (event: MessageEvent) => {
+  const { type, payload } = event.data;
+  // This will crash if event.data is null
+};
+
+// ✅ Good: Defensive null checking
+const handleMessage = (event: MessageEvent) => {
+  if (!event.data || typeof event.data !== 'object') {
+    console.warn('Invalid message data received');
+    return;
+  }
+  
+  const { type, payload } = event.data;
+  // Safe to proceed
+};
+```
+
+#### 2. Error Boundary Integration
+Integrate with React Error Boundaries to catch component-level errors:
+
+```typescript
+// ErrorBoundary should listen for recovery events
+class ErrorBoundary extends React.Component {
+  componentDidMount() {
+    window.addEventListener('svmseek-error-recovery', this.handleErrorRecovery);
+  }
+  
+  handleErrorRecovery = (event) => {
+    // Attempt to recover component state
+    this.setState({ hasError: false, error: null });
+  };
+}
+```
+
+### For API Integrations
+
+#### 1. Timeout Handling
+Use centralized timeout constants:
+
+```typescript
+import { TIMEOUT_CONSTANTS } from '../utils/constants';
+
+const apiCall = async () => {
+  const controller = new AbortController();
+  const timeoutId = setTimeout(
+    () => controller.abort(),
+    TIMEOUT_CONSTANTS.NETWORK_REQUEST
+  );
+  
+  try {
+    const response = await fetch('/api/data', {
+      signal: controller.signal
+    });
+    return await response.json();
+  } finally {
+    clearTimeout(timeoutId);
+  }
+};
+```
+
+#### 2. Retry Logic
+Implement exponential backoff for failed requests:
+
+```typescript
+import { getRetryDelay, ERROR_CONSTANTS } from '../utils/constants';
+
+const retryableApiCall = async (attempt = 0) => {
+  try {
+    return await apiCall();
+  } catch (error) {
+    if (attempt < ERROR_CONSTANTS.MAX_RETRIES) {
+      const delay = getRetryDelay(attempt);
+      await new Promise(resolve => setTimeout(resolve, delay));
+      return retryableApiCall(attempt + 1);
+    }
+    throw error;
+  }
+};
+```
+
+## Configuration
+
+### Error Handler Configuration
+
+```typescript
+import { GlobalErrorHandler } from './utils/globalErrorHandler';
+
+// Custom configuration
+const errorHandler = new GlobalErrorHandler({
+  enableRecovery: true,        // Enable automatic recovery attempts
+  enableLogging: true,         // Log errors to console
+  enableUserNotification: true // Dispatch user-facing events
+});
+
+errorHandler.initialize();
+```
+
+### Constants Configuration
+
+Modify timeout and error constants in `src/utils/constants.ts`:
+
+```typescript
+export const TIMEOUT_CONSTANTS = {
+  NETWORK_REQUEST: 10000,      // API request timeout
+  IFRAME_LOAD: 10000,          // Iframe loading timeout
+  MESSAGE_RESPONSE: 30000,     // Wallet message timeout
+  // ... other timeouts
+} as const;
+```
+
+## Testing Error Handling
+
+### Unit Tests
+Test error scenarios with mock failures:
+
+```typescript
+import { globalErrorHandler } from '../utils/globalErrorHandler';
+
+describe('Error Recovery', () => {
+  test('should recover from null data access', () => {
+    const mockEvent = new CustomEvent('svmseek-error-recovery');
+    const handler = jest.fn();
+    
+    window.addEventListener('svmseek-error-recovery', handler);
+    
+    // Simulate null data error
+    window.dispatchEvent(mockEvent);
+    
+    expect(handler).toHaveBeenCalled();
+  });
+});
+```
+
+### Integration Tests
+Test wallet extension conflicts:
+
+```typescript
+test('should handle wallet extension conflicts', () => {
+  // Simulate MetaMask defining ethereum
+  Object.defineProperty(window, 'ethereum', {
+    value: { isMetaMask: true },
+    configurable: false
+  });
+  
+  // Attempt to redefine (simulating Phantom)
+  try {
+    Object.defineProperty(window, 'ethereum', {
+      value: { isPhantom: true }
+    });
+  } catch (error) {
+    // Error should be caught and handled gracefully
+    expect(error.message).toContain('Cannot redefine property');
+  }
+});
+```
+
+## Best Practices
+
+### 1. Event Listener Cleanup
+Always clean up event listeners to prevent memory leaks:
+
+```typescript
+useEffect(() => {
+  const handleError = (event) => {
+    // Handle error recovery
+  };
+  
+  window.addEventListener('svmseek-error-recovery', handleError);
+  
+  return () => {
+    window.removeEventListener('svmseek-error-recovery', handleError);
+  };
+}, []);
+```
+
+### 2. Error Analytics
+Track error patterns for improvement:
+
+```typescript
+window.addEventListener('svmseek-error-recovery', (event) => {
+  // Send to analytics service
+  analytics.track('error_recovery', {
+    error_type: event.detail.errorType,
+    error_message: event.detail.errorMessage,
+    user_agent: navigator.userAgent,
+    timestamp: new Date().toISOString()
+  });
+});
+```
+
+### 3. User Experience
+Provide clear, actionable error messages:
+
+```typescript
+const showUserFriendlyError = (errorType, errorMessage) => {
+  const userMessages = {
+    wallet_conflict: {
+      title: 'Multiple Wallets Detected',
+      message: 'You have multiple wallet extensions installed. This might cause conflicts.',
+      action: 'Learn about wallet compatibility'
+    },
+    null_access: {
+      title: 'Temporary Issue',
+      message: 'We encountered a temporary issue but recovered automatically.',
+      action: 'No action needed'
+    }
+  };
+  
+  const config = userMessages[errorType] || {
+    title: 'Error Recovered',
+    message: 'An error occurred but was handled automatically.',
+    action: 'Continue using the app'
+  };
+  
+  showNotification(config);
+};
+```
+
+## Troubleshooting
+
+### Common Issues
+
+1. **Error Recovery Not Working**
+   - Check that `globalErrorHandler.initialize()` is called
+   - Verify event listeners are properly attached
+   - Check browser console for initialization errors
+
+2. **Too Many Recovery Events**
+   - Error handler limits recovery attempts per error type
+   - Check if error patterns indicate a deeper issue
+   - Review error statistics with `globalErrorHandler.getErrorStats()`
+
+3. **Wallet Extension Conflicts Persist**
+   - Some extensions may override our protection
+   - Consider showing user guidance to disable conflicting extensions
+   - Report specific extension combinations that cause issues
+
+### Debug Mode
+
+Enable debug logging for troubleshooting:
+
+```typescript
+import { GlobalErrorHandler } from './utils/globalErrorHandler';
+
+const debugErrorHandler = new GlobalErrorHandler({
+  enableLogging: true,
+  enableRecovery: true,
+  enableUserNotification: true
+});
+
+// Monitor error patterns
+setInterval(() => {
+  const stats = debugErrorHandler.getErrorStats();
+  if (Object.keys(stats).length > 0) {
+    console.log('Error stats:', stats);
+  }
+}, 30000);
+```
+
+## Future Improvements
+
+1. **Machine Learning Error Prediction**: Analyze error patterns to predict and prevent common failures
+2. **A/B Testing Recovery Strategies**: Test different recovery approaches to optimize user experience
+3. **Real-time Error Monitoring**: Integrate with error tracking services for production monitoring
+4. **Custom Error Recovery Policies**: Allow applications to define custom recovery strategies per error type