优化配送订单合同气瓶候选显示

backend/api/internal/logic/platform/gasorder/gasorder.go

@@ -62,9 +62,32 @@ func filterGasorderContractCandidates(query *gorm.DB, candidate string, now time
 	)
 }
 func GetGasorderContract(ctx *gin.Context) { getGasorderContract(ctx) }
+
+// ListGasorderContractProduct 在订单候选场景按合同收窄未解绑气瓶，未传合同时保留完整历史列表。
 func ListGasorderContractProduct(ctx *gin.Context) {
-	common.ListResource(ctx, &models.GasorderContractProduct{})
+	contractIdentity := strings.TrimSpace(ctx.Query("contract_identity"))
+	if contractIdentity == "" {
+		common.ListResource(ctx, &models.GasorderContractProduct{})
+		return
+	}
+	contractID, err := common.ResolveIdentityID(&models.GasorderContract{}, contractIdentity, true)
+	if err != nil {
+		common.RespondRecordError(ctx, err)
+		return
+	}
+	common.ListPageFiltered[models.GasorderContractProduct](ctx, func(query *gorm.DB) *gorm.DB {
+		return filterGasorderContractProductCandidates(query, contractID)
+	})
 }
+
+// filterGasorderContractProductCandidates 仅保留当前合同仍有效绑定的气瓶，并按类型和编码排序。
+func filterGasorderContractProductCandidates(query *gorm.DB, contractID uint64) *gorm.DB {
+	return query.
+		Where("gasorder_contract_id = ? AND unbound_at IS NULL", contractID).
+		Order("product_type_name asc").
+		Order("product_code asc")
+}
+
 func GetGasorderContractProduct(ctx *gin.Context) {
 	common.GetResource(ctx, &models.GasorderContractProduct{})
 }

backend/api/internal/logic/platform/gasorder/gasorder_test.go

@@ -71,6 +71,34 @@ func TestFilterGasorderContractCandidates(t *testing.T) {
 	}
 }
 
+// TestFilterGasorderContractProductCandidates 验证订单候选仅包含当前合同未解绑气瓶并按业务字段排序。
+func TestFilterGasorderContractProductCandidates(t *testing.T) {
+	sqlDatabase, _, err := sqlmock.New()
+	if err != nil {
+		t.Fatalf("创建模拟数据库失败：%v", err)
+	}
+	defer sqlDatabase.Close()
+	database, err := gorm.Open(postgres.New(postgres.Config{Conn: sqlDatabase}), &gorm.Config{})
+	if err != nil {
+		t.Fatalf("创建 GORM 数据库失败：%v", err)
+	}
+	statement := database.ToSQL(func(tx *gorm.DB) *gorm.DB {
+		var products []models.GasorderContractProduct
+		return filterGasorderContractProductCandidates(
+			tx.Model(&models.GasorderContractProduct{}), 27,
+		).Find(&products)
+	})
+	for _, fragment := range []string{
+		"gasorder_contract_id = 27",
+		"unbound_at IS NULL",
+		"ORDER BY product_type_name asc,product_code asc",
+	} {
+		if !strings.Contains(statement, fragment) {
+			t.Fatalf("合同气瓶候选缺少 %q：%s", fragment, statement)
+		}
+	}
+}
+
 func TestGasorderCreatorTypesCoverEveryConfirmedOrigin(t *testing.T) {
 	for _, creatorType := range []string{"user", "staff", "delivery", "gas"} {
 		if gasorderCreatorModels[creatorType] == nil {