feat(drafts): DB drafts with deferred numbering — create-as-draft (no number), assign number on finalize (offers/invoices/issued-orders)

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/services/issued-orders.service.ts

@@ -4,6 +4,7 @@ import {
   generateIssuedOrderNumber,
   previewIssuedOrderNumber,
   releaseIssuedOrderNumber,
+  assignIssuedOrderNumber,
 } from "./numbering.service";
 
 export interface IssuedOrderItemInput {
@@ -185,20 +186,29 @@ export async function getIssuedOrder(id: number) {
 
 export async function createIssuedOrder(body: IssuedOrderInput) {
   return prisma.$transaction(async (tx) => {
-    const poNumber =
+    const status = body.status ? String(body.status) : "draft";
+
+    // Deferred numbering: a draft carries NO po_number (the column is
+    // nullable-unique so many drafts coexist). The official number is consumed
+    // only when the draft is finalized (assignIssuedOrderNumber on draft->sent).
+    // A caller-supplied number, or a doc created already-finalized, numbers now.
+    const explicit =
       body.po_number !== undefined &&
       body.po_number !== null &&
       body.po_number !== ""
         ? String(body.po_number)
-        : (await generateIssuedOrderNumber(undefined, tx)).number;
+        : null;
+    const poNumber =
+      explicit ??
+      (status === "draft"
+        ? null
+        : (await generateIssuedOrderNumber(undefined, tx)).number);
 
     const order = await tx.issued_orders.create({
       data: {
         po_number: poNumber,
         customer_id: body.customer_id ? Number(body.customer_id) : null,
-        status: (body.status
-          ? String(body.status)
-          : "draft") as $Enums.issued_orders_status,
+        status: status as $Enums.issued_orders_status,
         currency: body.currency ? String(body.currency) : "CZK",
         vat_rate: body.vat_rate != null ? Number(body.vat_rate) : 21.0,
         apply_vat: body.apply_vat !== false,
@@ -299,7 +309,23 @@ export async function updateIssuedOrder(id: number, body: IssuedOrderInput) {
 
   if (body.status !== undefined) data.status = String(body.status);
 
-  await prisma.issued_orders.update({ where: { id }, data });
+  // Finalize transition draft -> sent: consume + write the official number
+  // ATOMICALLY with the status change, so there is never a window where the
+  // order is "sent" but still has a null po_number. assignIssuedOrderNumber is
+  // idempotent (won't re-number an order that already has a number).
+  const finalizing =
+    currentStatus === "draft" &&
+    body.status !== undefined &&
+    String(body.status) === "sent";
+
+  if (finalizing) {
+    await prisma.$transaction(async (tx) => {
+      await tx.issued_orders.update({ where: { id }, data });
+      await assignIssuedOrderNumber(id, tx);
+    });
+  } else {
+    await prisma.issued_orders.update({ where: { id }, data });
+  }
 
   if (editable && Array.isArray(body.items)) {
     await prisma.$transaction(async (tx) => {
@@ -321,7 +347,18 @@ export async function updateIssuedOrder(id: number, body: IssuedOrderInput) {
     });
   }
 
-  return { id, po_number: existing.po_number };
+  // Reflect the number the finalize transition just assigned (existing was read
+  // before the assign, so its po_number is still the pre-finalize null).
+  const poNumber = finalizing
+    ? ((
+        await prisma.issued_orders.findUnique({
+          where: { id },
+          select: { po_number: true },
+        })
+      )?.po_number ?? existing.po_number)
+    : existing.po_number;
+
+  return { id, po_number: poNumber };
 }
 
 export async function deleteIssuedOrder(id: number) {