Reportes de rentabilidad

// lib/services/reports.service.ts
import { prisma } from '@/lib/prisma'
import { Decimal } from 'decimal.js'

export async function getTechnicianProfitability(
  businessId: string,
  from: Date,
  to: Date
) {
  const orders = await prisma.serviceOrder.findMany({
    where: {
      businessId,             // multi-tenant OBLIGATORIO
      status: 'DELIVERED',
      createdAt: { gte: from, lte: to },
      technicianId: { not: null },
    },
    include: {
      technician: { select: { name: true } },
      parts: { select: { subtotal: true } },
    },
  })

  return orders.map(order => {
    const revenue    = new Decimal(order.cost.toString())
    const partsCost  = order.parts.reduce(
      (sum, p) => sum.plus(p.subtotal.toString()),
      new Decimal(0)
    )
    const margin = revenue.minus(partsCost)
    return {
      technicianName: order.technician?.name,
      revenue:  revenue.toFixed(2),
      cost:     partsCost.toFixed(2),
      margin:   margin.toFixed(2),
    }
  })
}