import { Injectable, Logger } from '@nestjs/common';
import { PrismaService } from '../../database/prisma.service';

@Injectable()
export class InvoicingService {
  private readonly logger = new Logger(InvoicingService.name);

  constructor(private prisma: PrismaService) {}

  async generateInvoice(orderId: string) {
    const order = await this.prisma.order.findUnique({
      where: { id: orderId },
      include: {
        items: true,
        tenant: true,
      },
    });

    if (!order) throw new Error('Order not found');

    const invoiceNumber = `INV-${new Date().getFullYear()}-${Math.floor(Math.random() * 90000) + 10000}`;

    // In a real app, we would use a PDF generation library (e.g., pdfkit, puppeteer)
    // For this implementation, we'll simulate the generation and return a mock URL
    this.logger.log(`Generating invoice ${invoiceNumber} for order ${orderId}`);

    const invoice = await this.prisma.invoice.create({
      data: {
        orderId: order.id,
        invoiceNumber,
        status: 'SENT',
        url: `https://storage.pazaryonetimi.com/invoices/${invoiceNumber}.pdf`,
      },
    });

    return invoice;
  }

  async getInvoices(tenantId: string) {
    return this.prisma.invoice.findMany({
      where: {
        order: {
          tenantId,
        },
      },
      include: {
        order: true,
      },
      orderBy: {
        createdAt: 'desc',
      },
    });
  }
}