同步支持动态更新取件码长度，调整存量取件码以适配新长度并优化相关逻辑和文档。

internal/service/upload_service.go

@@ -6,9 +6,7 @@ import (
 	"FileRelay/internal/model"
 	"FileRelay/internal/storage"
 	"context"
-	"crypto/rand"
 	"fmt"
-	"math/big"
 	"mime/multipart"
 	"path/filepath"
 	"time"
@@ -27,7 +25,8 @@ func NewUploadService() *UploadService {
 
 func (s *UploadService) CreateBatch(ctx context.Context, files []*multipart.FileHeader, remark string, expireType string, expireValue interface{}) (*model.FileBatch, error) {
 	// 1. 生成取件码
-	pickupCode, err := s.generatePickupCode(config.GlobalConfig.Security.PickupCodeLength)
+	batchService := NewBatchService()
+	pickupCode, err := batchService.GeneratePickupCode(config.GlobalConfig.Security.PickupCodeLength)
 	if err != nil {
 		return nil, err
 	}
@@ -63,7 +62,8 @@ func (s *UploadService) CreateBatch(ctx context.Context, files []*multipart.File
 
 func (s *UploadService) CreateTextBatch(ctx context.Context, content string, remark string, expireType string, expireValue interface{}) (*model.FileBatch, error) {
 	// 1. 生成取件码
-	pickupCode, err := s.generatePickupCode(config.GlobalConfig.Security.PickupCodeLength)
+	batchService := NewBatchService()
+	pickupCode, err := batchService.GeneratePickupCode(config.GlobalConfig.Security.PickupCodeLength)
 	if err != nil {
 		return nil, err
 	}
@@ -136,22 +136,3 @@ func (s *UploadService) processFile(ctx context.Context, tx *gorm.DB, batchID st
 
 	return item, nil
 }
-
-func (s *UploadService) generatePickupCode(length int) (string, error) {
-	const charset = "0123456789"
-	b := make([]byte, length)
-	for i := range b {
-		num, err := rand.Int(rand.Reader, big.NewInt(int64(len(charset))))
-		if err != nil {
-			return "", err
-		}
-		b[i] = charset[num.Int64()]
-	}
-	// 检查是否冲突
-	var count int64
-	s.db.Model(&model.FileBatch{}).Where("pickup_code = ? AND status = ?", string(b), "active").Count(&count)
-	if count > 0 {
-		return s.generatePickupCode(length) // 递归生成
-	}
-	return string(b), nil
-}