---
description: Channel integration patterns for Evolution API
globs:
  - "src/api/integrations/channel/**/*.ts"
alwaysApply: false
---

# Evolution API Channel Integration Rules

## Channel Controller Pattern

### Base Channel Controller
```typescript
export interface ChannelControllerInterface {
  integrationEnabled: boolean;
}

export class ChannelController {
  public prismaRepository: PrismaRepository;
  public waMonitor: WAMonitoringService;

  constructor(prismaRepository: PrismaRepository, waMonitor: WAMonitoringService) {
    this.prisma = prismaRepository;
    this.monitor = waMonitor;
  }

  public set prisma(prisma: PrismaRepository) {
    this.prismaRepository = prisma;
  }

  public get prisma() {
    return this.prismaRepository;
  }

  public set monitor(waMonitor: WAMonitoringService) {
    this.waMonitor = waMonitor;
  }

  public get monitor() {
    return this.waMonitor;
  }

  public init(instanceData: InstanceDto, data: ChannelDataType) {
    if (!instanceData.token && instanceData.integration === Integration.WHATSAPP_BUSINESS) {
      throw new BadRequestException('token is required');
    }

    if (instanceData.integration === Integration.WHATSAPP_BUSINESS) {
      return new BusinessStartupService(/* dependencies */);
    }

    if (instanceData.integration === Integration.WHATSAPP_BAILEYS) {
      return new BaileysStartupService(/* dependencies */);
    }

    return null;
  }
}
```

## Channel Service Pattern

### Base Channel Service
```typescript
export class ChannelStartupService {
  constructor(
    private readonly configService: ConfigService,
    private readonly eventEmitter: EventEmitter2,
    private readonly prismaRepository: PrismaRepository,
    public readonly cache: CacheService,
    public readonly chatwootCache: CacheService,
  ) {}

  public readonly logger = new Logger('ChannelStartupService');

  public client: WASocket;
  public readonly instance: wa.Instance = {};
  public readonly localChatwoot: wa.LocalChatwoot = {};
  public readonly localProxy: wa.LocalProxy = {};
  public readonly localSettings: wa.LocalSettings = {};
  public readonly localWebhook: wa.LocalWebHook = {};

  public setInstance(instance: InstanceDto) {
    this.logger.setInstance(instance.instanceName);

    this.instance.name = instance.instanceName;
    this.instance.id = instance.instanceId;
    this.instance.integration = instance.integration;
    this.instance.number = instance.number;
    this.instance.token = instance.token;
    this.instance.businessId = instance.businessId;

    if (this.configService.get<Chatwoot>('CHATWOOT').ENABLED && this.localChatwoot?.enabled) {
      this.chatwootService.eventWhatsapp(
        Events.STATUS_INSTANCE,
        { instanceName: this.instance.name },
        {
          instance: this.instance.name,
          status: 'created',
        },
      );
    }
  }

  public set instanceName(name: string) {
    this.logger.setInstance(name);
    this.instance.name = name;
  }

  public get instanceName() {
    return this.instance.name;
  }
}
```

## Business API Service Pattern

### Meta Business Service
```typescript
export class BusinessStartupService extends ChannelStartupService {
  constructor(
    configService: ConfigService,
    eventEmitter: EventEmitter2,
    prismaRepository: PrismaRepository,
    cache: CacheService,
    chatwootCache: CacheService,
    baileysCache: CacheService,
    providerFiles: ProviderFiles,
  ) {
    super(configService, eventEmitter, prismaRepository, cache, chatwootCache);
  }

  public async sendMessage(data: SendTextDto): Promise<any> {
    const businessConfig = this.configService.get<WaBusiness>('WA_BUSINESS');
    
    const payload = {
      messaging_product: 'whatsapp',
      to: data.number,
      type: 'text',
      text: {
        body: data.text,
      },
    };

    try {
      const response = await axios.post(
        `${businessConfig.URL}/${businessConfig.VERSION}/${this.instance.businessId}/messages`,
        payload,
        {
          headers: {
            'Authorization': `Bearer ${this.instance.token}`,
            'Content-Type': 'application/json',
          },
        }
      );

      return response.data;
    } catch (error) {
      this.logger.error(`Business API call failed: ${error.message}`);
      throw new BadRequestException('Failed to send message via Business API');
    }
  }

  public async receiveWebhook(data: any): Promise<void> {
    // Process incoming webhook from Meta Business API
    const { entry } = data;
    
    for (const entryItem of entry) {
      const { changes } = entryItem;
      
      for (const change of changes) {
        if (change.field === 'messages') {
          await this.processMessage(change.value);
        }
      }
    }
  }

  private async processMessage(messageData: any): Promise<void> {
    // Process incoming message from Business API
    const { messages, contacts } = messageData;
    
    if (messages) {
      for (const message of messages) {
        await this.handleIncomingMessage(message, contacts);
      }
    }
  }

  private async handleIncomingMessage(message: any, contacts: any[]): Promise<void> {
    // Handle individual message
    const contact = contacts?.find(c => c.wa_id === message.from);
    
    // Emit event for message processing
    this.eventEmitter.emit(Events.MESSAGES_UPSERT, {
      instanceName: this.instance.name,
      message,
      contact,
    });
  }
}
```

## Baileys Service Pattern

### Baileys Integration Service
```typescript
export class BaileysStartupService extends ChannelStartupService {
  constructor(
    configService: ConfigService,
    eventEmitter: EventEmitter2,
    prismaRepository: PrismaRepository,
    cache: CacheService,
    chatwootCache: CacheService,
    baileysCache: CacheService,
    providerFiles: ProviderFiles,
  ) {
    super(configService, eventEmitter, prismaRepository, cache, chatwootCache);
  }

  public async connectToWhatsapp(): Promise<void> {
    const authPath = path.join(INSTANCE_DIR, this.instance.name);
    const { state, saveCreds } = await useMultiFileAuthState(authPath);

    this.client = makeWASocket({
      auth: state,
      logger: P({ level: 'error' }),
      printQRInTerminal: false,
      browser: ['Evolution API', 'Chrome', '4.0.0'],
      defaultQueryTimeoutMs: 60000,
    });

    this.setupEventHandlers();
    this.client.ev.on('creds.update', saveCreds);
  }

  private setupEventHandlers(): void {
    this.client.ev.on('connection.update', (update) => {
      this.handleConnectionUpdate(update);
    });

    this.client.ev.on('messages.upsert', ({ messages, type }) => {
      this.handleIncomingMessages(messages, type);
    });

    this.client.ev.on('messages.update', (updates) => {
      this.handleMessageUpdates(updates);
    });

    this.client.ev.on('contacts.upsert', (contacts) => {
      this.handleContactsUpdate(contacts);
    });

    this.client.ev.on('chats.upsert', (chats) => {
      this.handleChatsUpdate(chats);
    });
  }

  private async handleConnectionUpdate(update: ConnectionUpdate): Promise<void> {
    const { connection, lastDisconnect, qr } = update;

    if (qr) {
      this.instance.qrcode = {
        count: this.instance.qrcode?.count ? this.instance.qrcode.count + 1 : 1,
        base64: qr,
      };

      this.eventEmitter.emit(Events.QRCODE_UPDATED, {
        instanceName: this.instance.name,
        qrcode: this.instance.qrcode,
      });
    }

    if (connection === 'close') {
      const shouldReconnect = (lastDisconnect?.error as Boom)?.output?.statusCode !== DisconnectReason.loggedOut;
      
      if (shouldReconnect) {
        this.logger.log('Connection closed, reconnecting...');
        await this.connectToWhatsapp();
      } else {
        this.logger.log('Connection closed, logged out');
        this.eventEmitter.emit(Events.LOGOUT_INSTANCE, {
          instanceName: this.instance.name,
        });
      }
    }

    if (connection === 'open') {
      this.logger.log('Connection opened successfully');
      this.instance.wuid = this.client.user?.id;
      
      this.eventEmitter.emit(Events.CONNECTION_UPDATE, {
        instanceName: this.instance.name,
        state: 'open',
      });
    }
  }

  public async sendMessage(data: SendTextDto): Promise<any> {
    const jid = createJid(data.number);
    
    const message = {
      text: data.text,
    };

    if (data.linkPreview !== undefined) {
      message.linkPreview = data.linkPreview;
    }

    if (data.mentionsEveryOne) {
      // Handle mentions
    }

    try {
      const response = await this.client.sendMessage(jid, message);
      return response;
    } catch (error) {
      this.logger.error(`Failed to send message: ${error.message}`);
      throw new BadRequestException('Failed to send message');
    }
  }
}
```

## Channel Router Pattern

### Channel Router Structure
```typescript
export class ChannelRouter {
  public readonly router: Router;

  constructor(configService: any, ...guards: any[]) {
    this.router = Router();

    this.router.use('/', new MetaRouter(configService).router);
    this.router.use('/baileys', new BaileysRouter(...guards).router);
  }
}
```

## Integration Types

### Channel Data Types
```typescript
type ChannelDataType = {
  configService: ConfigService;
  eventEmitter: EventEmitter2;
  prismaRepository: PrismaRepository;
  cache: CacheService;
  chatwootCache: CacheService;
  baileysCache: CacheService;
  providerFiles: ProviderFiles;
};

export enum Integration {
  WHATSAPP_BUSINESS = 'WHATSAPP-BUSINESS',
  WHATSAPP_BAILEYS = 'WHATSAPP-BAILEYS',
}
```

## Error Handling in Channels

### Channel-Specific Error Handling
```typescript
// CORRECT - Channel-specific error handling
public async sendMessage(data: SendTextDto): Promise<any> {
  try {
    const response = await this.channelSpecificSend(data);
    return response;
  } catch (error) {
    this.logger.error(`${this.constructor.name} send failed: ${error.message}`);
    
    if (error.response?.status === 401) {
      throw new UnauthorizedException('Invalid token for channel');
    }
    
    if (error.response?.status === 429) {
      throw new BadRequestException('Rate limit exceeded');
    }
    
    throw new InternalServerErrorException('Channel communication failed');
  }
}
```

## Channel Testing Pattern

Tests for channel services should mock dependencies and verify behavior for message sending, connection handling, and error cases.