svr-imp/src/services/create-printer.ts

import { Injectable } from '@nestjs/common';
import { InjectQueue } from '@nestjs/bullmq';
import { Queue } from 'bullmq';
import { PrintDataDto } from '../dto/print-data.dto';
import { PrintHtmlDto } from '../dto/print-html.dto';
import { ThermalPrinter, PrinterTypes } from 'node-thermal-printer';

@Injectable()
export class ListPrinterService {
  private readonly printerType = PrinterTypes.EPSON;

  constructor(@InjectQueue('printer') private printerQueue: Queue) {}

  async printReceipt(data: PrintDataDto): Promise<{ success: boolean; message: string }> {
    if (!data.lines?.length) {
      return { success: false, message: 'No lines provided' };
    }

    try {
      let printerInterface = data.printerInterface;

      if (printerInterface && !printerInterface.includes('://') && !printerInterface.startsWith('printer:')) {
        printerInterface = `printer:${printerInterface}`;
      }

      const printer = new ThermalPrinter({
        type: this.printerType,
        interface: printerInterface,
      });

      this.applyAlignment(printer, data.alignment);

      for (const line of data.lines) {
        if (data.upsideDown) {
          printer.upsideDown(true);
        }
        printer.println(line);
        if (data.upsideDown) {
          printer.upsideDown(false);
        }
      }

      printer.drawLine();
      printer.beep();

      await printer.execute();
      
      return { success: true, message: 'Print successful!' };
    } catch (error) {
      return { 
        success: false, 
        message: `Print failed: ${error.message || error}` 
      };
    }
  }

  private applyAlignment(printer: any, alignment?: string): void {
    if (alignment === 'center') {
      return printer.alignCenter();
    }
    
    if (alignment === 'right') {
      return printer.alignRight();
    }

    return printer.alignLeft();
  }

  async printHtml(data: PrintHtmlDto): Promise<{ success: boolean; message: string; jobId?: string }> {
    const jobOptions: any = {};
    
    if (data.jobId) {
      const safeJobId = /^\d+$/.test(data.jobId) ? `print-${data.jobId}` : data.jobId;
      jobOptions.jobId = safeJobId;
    }

    const job = await this.printerQueue.add('print-html-job', data, jobOptions);

    return { 
      success: true, 
      message: 'Tarefa enviada para a fila de impressão',
      jobId: job.id 
    };
  }
}