优化结构

internal/data/system/list.go

@@ -0,0 +1,42 @@
+package system
+
+import (
+	"kra/pkg/database/pagination"
+
+	"gorm.io/gorm"
+)
+
+// listRows centralizes the storage-only part shared by simple repositories:
+// count the filtered query, apply the bounded page, load POs, and convert them
+// at the data/biz boundary. Domain-specific filters and ordering stay in each
+// repository.
+func queryRows[PO any](db *gorm.DB, page, size int, paginate, required bool) ([]PO, int64, error) {
+	var total int64
+	if err := db.Count(&total).Error; err != nil {
+		return nil, 0, err
+	}
+	if paginate {
+		if required {
+			db = pagination.ApplyRequired(db, page, size, 100)
+		} else {
+			db = pagination.Apply(db, page, size, 100)
+		}
+	}
+	var pos []PO
+	if err := db.Find(&pos).Error; err != nil {
+		return nil, 0, err
+	}
+	return pos, total, nil
+}
+
+func listRows[PO any, DO any](db *gorm.DB, page, size int, paginate bool, convert func(PO) *DO) ([]*DO, int64, error) {
+	pos, total, err := queryRows[PO](db, page, size, paginate, false)
+	if err != nil {
+		return nil, 0, err
+	}
+	out := make([]*DO, 0, len(pos))
+	for _, po := range pos {
+		out = append(out, convert(po))
+	}
+	return out, total, nil
+}