// SPDX-License-Identifier: LicenseRef-ConusAI-Template-1.0
import { badRequest, conflict } from "@conusai-kit/core"
import type { InvoiceTerms } from "../contract/index.js"
import type { InvoicingService } from "./ports.js"
export const operationKey = (operation: string, requestId: string) => `invoicing:${operation}:${requestId}`
export function validateTerms(data: InvoiceTerms): InvoiceTerms {
  if (
    data.lines.some((line) => line.net_price.currency !== data.currency) ||
    data.allowances_charges?.some((charge) => charge.amount.currency !== data.currency)
  )
    throw badRequest("Invoice currencies must match.")
  return data
}
export async function updateDraft(
  service: InvoicingService,
  input: { invoiceId: string; data: InvoiceTerms; expectedVersion: string; requestId: string },
) {
  const current = await service.get(input.invoiceId)
  // Prior revisions reach the service's idempotency ledger on response-loss retries.
  if (BigInt(input.expectedVersion) > BigInt(current.revision)) throw conflict("Reload the invoice before editing.")
  return service.update(
    input.invoiceId,
    validateTerms(input.data),
    input.expectedVersion,
    operationKey("update", input.requestId),
  )
}
export async function transitionInvoice(
  service: InvoicingService,
  operation: "issue" | "credit" | "void",
  input: {
    invoiceId: string
    expectedVersion: string
    requestId: string
    confirmed: true
    reason?: string
    seriesId?: string
  },
) {
  if (input.confirmed !== true) throw badRequest("Explicit confirmation is required.")
  // The service owns state/revision, retries, immutable numbering and fiscal retention.
  // No local allocation or predicted revision may substitute for that transaction.
  return service.transition(operation, {
    invoiceId: input.invoiceId,
    expectedVersion: input.expectedVersion,
    key: operationKey(operation, input.requestId),
    ...(input.reason ? { reason: input.reason } : {}),
    ...(input.seriesId ? { seriesId: input.seriesId } : {}),
  })
}