first commit

Smartes-Klassenzimmer-Backend/src/classroom/classroom.gateway.ts

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+import {
+  WebSocketGateway,
+  WebSocketServer,
+  SubscribeMessage,
+  MessageBody,
+  ConnectedSocket,
+  OnGatewayConnection,
+  OnGatewayDisconnect,
+} from '@nestjs/websockets';
+import { UseGuards } from '@nestjs/common';
+import { Server, Socket } from 'socket.io';
+import { JwtService } from '@nestjs/jwt';
+import { WsJwtGuard } from '../auth/guards';
+import { ClassroomService } from './classroom.service';
+
+@WebSocketGateway({
+  namespace: '/api/classroom',
+  cors: {
+    origin: [
+      'http://localhost:5173',
+      'http://127.0.0.1:5173',
+      'http://localhost:5500',
+      'http://127.0.0.1:5500',
+      'http://localhost:3000'
+    ],
+    credentials: true,
+  },
+})
+export class ClassroomGateway implements OnGatewayConnection, OnGatewayDisconnect {
+  @WebSocketServer()
+  server: Server;
+
+  constructor(
+    private readonly jwtService: JwtService,
+    private readonly classroomService: ClassroomService,
+  ) {}
+
+  handleConnection(client: Socket) {
+    try {
+      const token = this.extractTokenFromHandshake(client);
+
+      if (!token) {
+        console.log(`Classroom: Client ${client.id} rejected: No token`);
+        client.disconnect();
+        return;
+      }
+
+      const payload = this.jwtService.verify(token, {
+        secret: process.env.JWT_SECRET || 'your-super-secret-jwt-key-change-this-in-production',
+      });
+
+      client.data.user = payload;
+      
+      // Send current state to newly connected user
+      client.emit('state-update', {
+        raisedHands: this.classroomService.getRaisedHands(),
+        activeStudent: this.classroomService.getActiveStudent(),
+      });
+      
+    } catch (error) {
+      console.log(`Classroom: Client ${client.id} rejected: Invalid token`);
+      client.disconnect();
+    }
+  }
+
+  handleDisconnect(client: Socket) {
+    // Optional: automatically lower hand on disconnect? 
+    // For now, let's keep it persistent for 10 mins as per requirements.
+  }
+
+  private extractTokenFromHandshake(client: Socket): string | null {
+    const cookies = client.handshake.headers.cookie;
+    if (cookies) {
+      const cookieArray = cookies.split(';');
+      for (const cookie of cookieArray) {
+        const [name, value] = cookie.trim().split('=');
+        if (name === 'access_token') {
+          return value;
+        }
+      }
+    }
+    return client.handshake.auth?.token || (client.handshake.query?.token as string) || null;
+  }
+
+  private broadcastState() {
+    this.server.emit('state-update', {
+      raisedHands: this.classroomService.getRaisedHands(),
+      activeStudent: this.classroomService.getActiveStudent(),
+    });
+  }
+
+  @UseGuards(WsJwtGuard)
+  @SubscribeMessage('raise-hand')
+  handleRaiseHand(
+    @MessageBody() data: { type: 'normal' | 'question' },
+    @ConnectedSocket() client: Socket,
+  ) {
+    const user = client.data.user;
+    this.classroomService.raiseHand(user.sub, user.username, data.type, (userId) => {
+        // Callback for timeout
+        this.classroomService.lowerHand(userId);
+        this.broadcastState();
+    });
+    this.broadcastState();
+  }
+
+  @UseGuards(WsJwtGuard)
+  @SubscribeMessage('lower-hand')
+  handleLowerHand(@ConnectedSocket() client: Socket) {
+    const user = client.data.user;
+    this.classroomService.lowerHand(user.sub);
+    this.broadcastState();
+  }
+
+  @UseGuards(WsJwtGuard)
+  @SubscribeMessage('lower-all-hands')
+  handleLowerAllHands(@ConnectedSocket() client: Socket) {
+    const user = client.data.user;
+    if (user.role !== 'Lehrer') {
+        client.emit('error', { message: 'Nur Lehrer können alle Hände senken.' });
+        return; 
+    }
+    this.classroomService.lowerAllHands();
+    this.broadcastState();
+  }
+
+  @UseGuards(WsJwtGuard)
+  @SubscribeMessage('pick-student')
+  handlePickStudent(
+    @MessageBody() data: { userId: number },
+    @ConnectedSocket() client: Socket,
+  ) {
+    const user = client.data.user;
+    if (user.role !== 'Lehrer') {
+      client.emit('error', { message: 'Nur Lehrer können Schüler aufrufen.' });
+      return;
+    }
+
+    const hands = this.classroomService.getRaisedHands();
+    const target = hands.find(h => h.userId === data.userId);
+    
+    if (target) {
+        this.classroomService.setActiveStudent(target.userId, target.username);
+        this.broadcastState();
+    }
+  }
+
+  @UseGuards(WsJwtGuard)
+  @SubscribeMessage('pick-random')
+  handlePickRandom(@ConnectedSocket() client: Socket) {
+    const user = client.data.user;
+    if (user.role !== 'Lehrer') {
+      client.emit('error', { message: 'Nur Lehrer können Zufallsauswahl nutzen.' });
+      return;
+    }
+
+    this.classroomService.pickRandomStudent();
+    this.broadcastState();
+  }
+  
+  @UseGuards(WsJwtGuard)
+  @SubscribeMessage('reset-active')
+  handleResetActive(@ConnectedSocket() client: Socket) {
+     const user = client.data.user;
+     const activeStudent = this.classroomService.getActiveStudent();
+     
+     // Allow if teacher OR if the requesting user is the active student
+     const isActiveStudent = activeStudent && activeStudent.userId === user.sub;
+     
+     if (user.role !== 'Lehrer' && !isActiveStudent) {
+       client.emit('error', { message: 'Nur Lehrer oder der aktive Schüler können die Auswahl zurücksetzen.' });
+       return;
+     }
+     
+     this.classroomService.clearActiveStudent();
+     this.broadcastState();
+  }
+}