fix: retrofit AssetItem.model to modelId FK

AssetItem.model was a free-text string with no referential integrity.
Now a required FK to AssetModel, mirroring the Request.employeeId and
License.vendorId retrofit precedent (no backfill needed, no real
AssetItem data existed).

src/app/api/assets/route.ts

@@ -22,11 +22,11 @@ export async function POST(request: Request): Promise<NextResponse> {
     return NextResponse.json({ error: "Request body must be a JSON object" }, { status: 400 });
   }
 
-  const { serialNumber, model, purchaseDate, warrantyEndDate, purchaseOrderId } =
+  const { serialNumber, modelId, purchaseDate, warrantyEndDate, purchaseOrderId } =
     body as Record<string, unknown>;
   const validation = validateCreateAssetItemInput({
     serialNumber,
-    model,
+    modelId,
     purchaseDate,
     warrantyEndDate,
     purchaseOrderId,

src/lib/assets.ts

@@ -7,7 +7,7 @@ export type AssetItemStatus = "in_stock" | "assigned" | "repair" | "retired";
 export interface AssetItemRecord {
   id: string;
   serial_number: string;
-  model: string;
+  model_id: string;
   purchase_date: string;
   warranty_end_date: string | null;
   status: AssetItemStatus;
@@ -17,7 +17,7 @@ export interface AssetItemRecord {
 
 export interface CreateAssetItemInput {
   serialNumber: string;
-  model: string;
+  modelId: string;
   purchaseDate: Date;
   warrantyEndDate?: Date;
   purchaseOrderId?: string | null;
@@ -47,7 +47,15 @@ function dateString(message: string) {
 
 const createAssetItemSchema = z.object({
   serialNumber: nonEmptyString("serialNumber is required and must be a non-empty string"),
-  model: nonEmptyString("model is required and must be a non-empty string"),
+  // Required FK to AssetModel — replaced the free-text `model` String (see
+  // schema.prisma / docs/asset-license-management.md's "Cập nhật 2026-08-02
+  // (2)" section). Only a UUID *format* check here, whether it references a
+  // real AssetModel is left to Prisma's own FK constraint at insert time
+  // (see createAssetItem()'s P2003 handling below). Mirrors
+  // src/lib/licenses.ts's vendorId handling.
+  modelId: z
+    .string({ required_error: "modelId is required and must be a valid UUID string" })
+    .uuid("modelId is required and must be a valid UUID string"),
   purchaseDate: dateString("purchaseDate is required and must be a valid date string"),
   warrantyEndDate: dateString("warrantyEndDate must be a valid date string").optional(),
   // FK to PurchaseOrder — nullable/optional, supply-side traceability (not
@@ -64,17 +72,17 @@ const createAssetItemSchema = z.object({
 });
 
 /**
- * Validates raw (untyped) asset-item-creation input. serialNumber/model
- * must be non-empty strings, purchaseDate must be a valid date string,
- * warrantyEndDate is optional but must be a valid date string if present.
- * purchaseOrderId is optional/nullable but must be a valid UUID if present.
- * status is not accepted here — new assets always start "in_stock" (same
- * pattern as Request always starting "Draft"), later states are set via
- * other operations, not at creation.
+ * Validates raw (untyped) asset-item-creation input. serialNumber must be a
+ * non-empty string, modelId must be a valid UUID string, purchaseDate must
+ * be a valid date string, warrantyEndDate is optional but must be a valid
+ * date string if present. purchaseOrderId is optional/nullable but must be
+ * a valid UUID if present. status is not accepted here — new assets always
+ * start "in_stock" (same pattern as Request always starting "Draft"), later
+ * states are set via other operations, not at creation.
  */
 export function validateCreateAssetItemInput(input: {
   serialNumber?: unknown;
-  model?: unknown;
+  modelId?: unknown;
   purchaseDate?: unknown;
   warrantyEndDate?: unknown;
   purchaseOrderId?: unknown;
@@ -90,7 +98,7 @@ export function validateCreateAssetItemInput(input: {
 function toRecord(row: {
   id: string;
   serialNumber: string;
-  model: string;
+  modelId: string;
   purchaseDate: Date;
   warrantyEndDate: Date | null;
   status: AssetItemStatus;
@@ -100,7 +108,7 @@ function toRecord(row: {
   return {
     id: row.id,
     serial_number: row.serialNumber,
-    model: row.model,
+    model_id: row.modelId,
     purchase_date: row.purchaseDate.toISOString(),
     warranty_end_date: row.warrantyEndDate ? row.warrantyEndDate.toISOString() : null,
     status: row.status,
@@ -119,10 +127,14 @@ export type CreateAssetItemResult =
  * caught here and translated into the same `{ok:false,error}` shape as
  * input validation failures, rather than letting a raw Prisma error leak
  * to the API layer. Mirrors createEmployee()/createRequest()'s P2003
- * handling for FK violations. If purchaseOrderId doesn't reference an
- * existing PurchaseOrder, Prisma raises P2003 (FK constraint violation) —
- * caught the same way, mirrors src/lib/purchase-orders.ts's
- * createPurchaseOrder() P2003 handling.
+ * handling for FK violations. Two separate FKs can fail here (modelId ->
+ * AssetModel, purchaseOrderId -> PurchaseOrder) — Prisma raises the same
+ * error code (P2003) for either, so the FK constraint name in
+ * `error.meta.field_name` is used to tell them apart and return a targeted
+ * message, rather than a raw Prisma error leaking to the API layer. Mirrors
+ * src/lib/licenses.ts's createLicense() / src/lib/purchase-orders.ts's
+ * createPurchaseOrder() pattern for disambiguating between two FKs on the
+ * same model.
  */
 export async function createAssetItem(
   input: CreateAssetItemInput
@@ -131,7 +143,7 @@ export async function createAssetItem(
     const created = await prisma.assetItem.create({
       data: {
         serialNumber: input.serialNumber,
-        model: input.model,
+        modelId: input.modelId,
         purchaseDate: input.purchaseDate,
         warrantyEndDate: input.warrantyEndDate ?? null,
         purchaseOrderId: input.purchaseOrderId ?? null,
@@ -143,7 +155,11 @@ export async function createAssetItem(
       return { ok: false, error: "serialNumber already exists" };
     }
     if (error instanceof Prisma.PrismaClientKnownRequestError && error.code === "P2003") {
-      return { ok: false, error: "purchaseOrderId does not reference an existing purchase order" };
+      const fieldName = typeof error.meta?.field_name === "string" ? error.meta.field_name : "";
+      if (fieldName.includes("purchase_order")) {
+        return { ok: false, error: "purchaseOrderId does not reference an existing purchase order" };
+      }
+      return { ok: false, error: "modelId does not reference an existing asset model" };
     }
     throw error;
   }