feat: enhance JWT default guard with admin authentication validation

- Implemented comprehensive JWT validation for admin users
- Added checks to verify admin user's identity and role
- Integrated QueryBus to fetch and validate admin entity details
- Improved security by cross-referencing JWT payload with database records

Author: kastov

src/common/guards/jwt-guards/def-jwt-guard.ts

@@ -1,3 +1,55 @@
+import { ExecutionContext, Injectable } from '@nestjs/common';
 import { AuthGuard } from '@nestjs/passport';
+import { QueryBus } from '@nestjs/cqrs';
 
-export class JwtDefaultGuard extends AuthGuard('registeredUserJWT') {}
+import { ICommandResponse } from '@common/types/command-response.type';
+import { ROLE } from '@libs/contracts/constants';
+
+import { GetAdminByUsernameQuery } from '@modules/admin/queries/get-admin-by-username/get-admin-by-username.query';
+import { AdminEntity } from '@modules/admin/entities/admin.entity';
+import { IJWTAuthPayload } from '@modules/auth/interfaces';
+
+@Injectable()
+export class JwtDefaultGuard extends AuthGuard('registeredUserJWT') {
+    constructor(private readonly queryBus: QueryBus) {
+        super();
+    }
+
+    async canActivate(context: ExecutionContext): Promise<boolean> {
+        const isJwtValid = await super.canActivate(context);
+        if (!isJwtValid) {
+            return false;
+        }
+
+        const { user } = context.switchToHttp().getRequest<{ user: IJWTAuthPayload }>();
+
+        if (!user || !user.username || !user.role) {
+            return false;
+        }
+
+        if (user.role === ROLE.ADMIN) {
+            const adminEntity = await this.getAdminByUsername({
+                username: user.username,
+                role: user.role,
+            });
+
+            if (!adminEntity.isOk || !adminEntity.response) {
+                return false;
+            }
+
+            if (adminEntity.response.uuid !== user.uuid) {
+                return false;
+            }
+        }
+
+        return true;
+    }
+
+    private async getAdminByUsername(
+        dto: GetAdminByUsernameQuery,
+    ): Promise<ICommandResponse<AdminEntity>> {
+        return this.queryBus.execute<GetAdminByUsernameQuery, ICommandResponse<AdminEntity>>(
+            new GetAdminByUsernameQuery(dto.username, dto.role),
+        );
+    }
+}