Backend Complete: Interface Refactoring & Service Container Enhancements

Repository Interface Optimization:
- Created IBaseRepository.ts and IPaginatedRepository.ts
- Refactored all 7 repository interfaces to extend base interfaces
- Eliminated ~200 lines of redundant code (70% reduction)
- Improved type safety and maintainability

 Dependency Injection Improvements:
- Added EmailService and GameTokenService to DIContainer
- Updated CreateUserCommandHandler constructor for DI
- Updated RequestPasswordResetCommandHandler constructor for DI
- Enhanced testability and service consistency

 Environment Configuration:
- Created comprehensive .env.example with 40+ variables
- Organized into 12 logical sections (Database, Security, Email, etc.)
- Added security guidelines and best practices
- Documented all backend environment requirements

 Documentation:
- Added comprehensive codebase review
- Created refactoring summary report
- Added frontend implementation guide

Impact: Improved code quality, reduced maintenance overhead, enhanced developer experience

SerpentRace_Backend/src/Application/Services/AuthMiddleware.ts

@@ -0,0 +1,146 @@
+import { Request, Response, NextFunction } from 'express';
+import { JWTService } from './JWTService';
+import { RedisService } from './RedisService';
+import { logAuth, logWarning } from './Logger';
+
+export const jwtService = new JWTService();
+const redisService = RedisService.getInstance();
+
+/**
+ * Check if a token is blacklisted
+ */
+async function isTokenBlacklisted(token: string): Promise<boolean> {
+    try {
+        const result = await redisService.get(`blacklist:${token}`);
+        return result === 'true';
+    } catch (error) {
+        // If Redis is down, allow the request to proceed (fail open)
+        logWarning('Failed to check token blacklist - allowing request', { error: (error as Error).message });
+        return false;
+    }
+}
+
+/**
+ * Extract token from request (cookie or Authorization header)
+ */
+function extractToken(req: Request): string | null {
+    // First try to get token from cookie
+    const cookieToken = req.cookies['auth_token'];
+    if (cookieToken) {
+        return cookieToken;
+    }
+    
+    // Fallback to Authorization header
+    const authHeader = req.headers.authorization;
+    if (authHeader && authHeader.startsWith('Bearer ')) {
+        return authHeader.substring(7);
+    }
+    
+    return null;
+}
+
+export async function authRequired(req: Request, res: Response, next: NextFunction) {
+    try {
+        // Extract token from request
+        const token = extractToken(req);
+        if (!token) {
+            logAuth('Authentication failed - No token provided', undefined, {
+                ip: req.ip,
+                userAgent: req.get ? req.get('User-Agent') : 'unknown',
+                path: req.path
+            }, req);
+            return res.status(401).json({ error: 'Unauthorized' });
+        }
+
+        // Check if token is blacklisted
+        const isBlacklisted = await isTokenBlacklisted(token);
+        if (isBlacklisted) {
+            logAuth('Authentication failed - Token blacklisted', undefined, {
+                ip: req.ip,
+                userAgent: req.get ? req.get('User-Agent') : 'unknown',
+                path: req.path
+            }, req);
+            return res.status(401).json({ error: 'Token has been invalidated' });
+        }
+
+        // Verify token
+        const payload = jwtService.verify(req);
+        if (!payload) {
+            logAuth('Authentication failed - Invalid token', undefined, {
+                ip: req.ip,
+                userAgent: req.get ? req.get('User-Agent') : 'unknown',
+                path: req.path
+            }, req);
+            return res.status(401).json({ error: 'Unauthorized' });
+        }
+        
+        logAuth('Authentication successful', payload.userId, {
+            authLevel: payload.authLevel,
+            orgId: payload.orgId
+        }, req);
+        
+        const refreshed = jwtService.refreshIfNeeded(payload, res);
+        if (refreshed) {
+            logAuth('Token refreshed', payload.userId, undefined, req);
+        }
+        
+        (req as any).user = payload;
+        next();
+    } catch (error) {
+        logWarning('Authentication middleware error', { error: (error as Error).message }, req);
+        return res.status(500).json({ error: 'Internal server error' });
+    }
+}
+
+export async function adminRequired(req: Request, res: Response, next: NextFunction) {
+    try {
+        // Extract token from request
+        const token = extractToken(req);
+        if (!token) {
+            logWarning('Admin access denied - No token provided', {
+                ip: req.ip,
+                path: req.path
+            }, req);
+            return res.status(401).json({ error: 'Unauthorized' });
+        }
+
+        // Check if token is blacklisted
+        const isBlacklisted = await isTokenBlacklisted(token);
+        if (isBlacklisted) {
+            logWarning('Admin access denied - Token blacklisted', {
+                ip: req.ip,
+                path: req.path
+            }, req);
+            return res.status(401).json({ error: 'Token has been invalidated' });
+        }
+
+        // Verify token and check admin privileges
+        const payload = jwtService.verify(req);
+        if (!payload || payload.authLevel !== 1) {
+            logWarning('Admin access denied', {
+                hasPayload: !!payload,
+                authLevel: payload?.authLevel,
+                userId: payload?.userId,
+                ip: req.ip,
+                path: req.path
+            }, req);
+            return res.status(403).json({ error: 'Forbidden' });
+        }
+        
+        logAuth('Admin authentication successful', payload.userId, {
+            authLevel: payload.authLevel,
+            orgId: payload.orgId
+        }, req);
+        
+        const refreshed = jwtService.refreshIfNeeded(payload, res);
+        if (refreshed) {
+            logAuth('Admin token refreshed', payload.userId, undefined, req);
+        }
+        
+        (req as any).user = payload;
+        next();
+    } catch (error) {
+        logWarning('Admin authentication middleware error', { error: (error as Error).message }, req);
+        return res.status(500).json({ error: 'Internal server error' });
+    }
+}