修复(#8): 分组管理核心缺陷与测试覆盖 (#11)

Co-authored-by: multica-agent <github@multica.ai>

internal/logic/admin/group/helpers.go

@@ -0,0 +1,37 @@
+package group
+
+import (
+	"fmt"
+
+	"github.com/perfect-panel/server/internal/model/node"
+	"gorm.io/gorm"
+)
+
+const (
+	defaultPageSize = 20
+	maxPageSize     = 100
+)
+
+func normalizePagination(page, size int) (int, int) {
+	if page <= 0 {
+		page = 1
+	}
+	if size <= 0 {
+		size = defaultPageSize
+	}
+	if size > maxPageSize {
+		size = maxPageSize
+	}
+	return page, size
+}
+
+func countNodesInGroup(db *gorm.DB, nodeGroupId int64) (int, error) {
+	var count int64
+	err := db.Model(&node.Node{}).
+		Where("JSON_CONTAINS(node_group_ids, ?)", fmt.Sprintf("[%d]", nodeGroupId)).
+		Count(&count).Error
+	if err != nil {
+		return 0, err
+	}
+	return int(count), nil
+}