Feat[BE]: enhance transfer laying functionality with comprehensive filtering options and improved DTO structures

internal/utils/strings.go

@@ -2,6 +2,7 @@ package utils
 
 import (
 	"sort"
+	"strconv"
 	"strings"
 )
 
@@ -47,3 +48,54 @@ func ParseFlags(raw string) []string {
 	sort.Strings(res)
 	return res
 }
+
+// ParseQueryArray parses comma-separated string values and returns a slice of trimmed strings
+// Example: "a, b, c" → ["a", "b", "c"]
+func ParseQueryArray(raw string) []string {
+	if raw == "" {
+		return nil
+	}
+
+	parts := strings.Split(raw, ",")
+	result := make([]string, 0, len(parts))
+
+	for _, p := range parts {
+		trimmed := strings.TrimSpace(p)
+		if trimmed != "" {
+			result = append(result, trimmed)
+		}
+	}
+
+	if len(result) == 0 {
+		return nil
+	}
+	return result
+}
+
+// ParseQueryUintArray parses comma-separated string values and returns a slice of uint
+// Invalid values are skipped
+// Example: "1, 2, 3" → [1, 2, 3]
+func ParseQueryUintArray(raw string) []uint {
+	if raw == "" {
+		return nil
+	}
+
+	parts := strings.Split(raw, ",")
+	result := make([]uint, 0, len(parts))
+
+	for _, p := range parts {
+		trimmed := strings.TrimSpace(p)
+		if trimmed == "" {
+			continue
+		}
+
+		if num, err := strconv.ParseUint(trimmed, 10, 32); err == nil {
+			result = append(result, uint(num))
+		}
+	}
+
+	if len(result) == 0 {
+		return nil
+	}
+	return result
+}