update due date and range date

internal/validator/purchase_order_validator_test.go

@@ -0,0 +1,62 @@
+package validator
+
+import (
+	"testing"
+
+	"apskel-pos-be/internal/constants"
+	"apskel-pos-be/internal/contract"
+
+	"github.com/google/uuid"
+	"github.com/stretchr/testify/require"
+)
+
+func validCreatePurchaseOrderRequest() *contract.CreatePurchaseOrderRequest {
+	return &contract.CreatePurchaseOrderRequest{
+		VendorID:        uuid.New(),
+		PONumber:        "PO-001",
+		TransactionDate: "2026-05-29",
+		Items: []contract.CreatePurchaseOrderItemRequest{
+			{
+				IngredientID: uuid.New(),
+				Quantity:     1,
+				UnitID:       uuid.New(),
+				Amount:       1000,
+			},
+		},
+	}
+}
+
+func TestPurchaseOrderValidatorCreateAllowsMissingDueDate(t *testing.T) {
+	validator := NewPurchaseOrderValidator()
+
+	err, code := validator.ValidateCreatePurchaseOrderRequest(validCreatePurchaseOrderRequest())
+
+	require.NoError(t, err)
+	require.Empty(t, code)
+}
+
+func TestPurchaseOrderValidatorCreateRejectsInvalidDueDate(t *testing.T) {
+	validator := NewPurchaseOrderValidator()
+	req := validCreatePurchaseOrderRequest()
+	dueDate := "29-05-2026"
+	req.DueDate = &dueDate
+
+	err, code := validator.ValidateCreatePurchaseOrderRequest(req)
+
+	require.Error(t, err)
+	require.Equal(t, constants.MalformedFieldErrorCode, code)
+	require.Contains(t, err.Error(), "due_date must be in YYYY-MM-DD format")
+}
+
+func TestPurchaseOrderValidatorCreateRejectsDueDateBeforeTransactionDate(t *testing.T) {
+	validator := NewPurchaseOrderValidator()
+	req := validCreatePurchaseOrderRequest()
+	dueDate := "2026-05-28"
+	req.DueDate = &dueDate
+
+	err, code := validator.ValidateCreatePurchaseOrderRequest(req)
+
+	require.Error(t, err)
+	require.Equal(t, constants.MalformedFieldErrorCode, code)
+	require.Contains(t, err.Error(), "due_date must be after transaction_date")
+}