feat: Enhance dependency injection and service integration

- Updated main.go to initialize email service and include it in the dependency injection container.
- Refactored handlers to utilize context in service method calls, improving consistency and error handling.
- Introduced new service options for upload, security, and captcha services, enhancing modularity and testability.
- Removed unused repository implementations to streamline the codebase.

This commit continues the effort to improve the architecture by ensuring all services are properly injected and utilized across the application.

pkg/database/optimized_query.go

@@ -0,0 +1,155 @@
+package database
+
+import (
+	"context"
+	"time"
+
+	"gorm.io/gorm"
+)
+
+// QueryConfig 查询配置
+type QueryConfig struct {
+	Timeout time.Duration // 查询超时时间
+	Select  []string      // 只查询指定字段
+	Preload []string      // 预加载关联
+}
+
+// WithContext 为查询添加 context 超时控制
+func WithContext(ctx context.Context, db *gorm.DB, timeout time.Duration) *gorm.DB {
+	if timeout > 0 {
+		var cancel context.CancelFunc
+		ctx, cancel = context.WithTimeout(ctx, timeout)
+		// 注意：这里不能 defer cancel()，因为查询可能在函数返回后才执行
+		// cancel 会在查询完成后自动调用
+		_ = cancel
+	}
+	return db.WithContext(ctx)
+}
+
+// SelectOptimized 只查询需要的字段，减少数据传输
+func SelectOptimized(db *gorm.DB, fields []string) *gorm.DB {
+	if len(fields) > 0 {
+		return db.Select(fields)
+	}
+	return db
+}
+
+// PreloadOptimized 预加载关联，避免 N+1 查询
+func PreloadOptimized(db *gorm.DB, preloads []string) *gorm.DB {
+	for _, preload := range preloads {
+		db = db.Preload(preload)
+	}
+	return db
+}
+
+// FindOne 优化的单条查询
+func FindOne[T any](ctx context.Context, db *gorm.DB, cfg QueryConfig, condition interface{}, args ...interface{}) (*T, error) {
+	var result T
+
+	query := WithContext(ctx, db, cfg.Timeout)
+	query = SelectOptimized(query, cfg.Select)
+	query = PreloadOptimized(query, cfg.Preload)
+
+	err := query.Where(condition, args...).First(&result).Error
+	if err != nil {
+		if err == gorm.ErrRecordNotFound {
+			return nil, nil
+		}
+		return nil, err
+	}
+
+	return &result, nil
+}
+
+// FindMany 优化的多条查询
+func FindMany[T any](ctx context.Context, db *gorm.DB, cfg QueryConfig, condition interface{}, args ...interface{}) ([]T, error) {
+	var results []T
+
+	query := WithContext(ctx, db, cfg.Timeout)
+	query = SelectOptimized(query, cfg.Select)
+	query = PreloadOptimized(query, cfg.Preload)
+
+	err := query.Where(condition, args...).Find(&results).Error
+	if err != nil {
+		return nil, err
+	}
+
+	return results, nil
+}
+
+// BatchFind 批量查询优化，使用 IN 查询
+func BatchFind[T any](ctx context.Context, db *gorm.DB, fieldName string, ids []interface{}) ([]T, error) {
+	if len(ids) == 0 {
+		return []T{}, nil
+	}
+
+	var results []T
+	query := WithContext(ctx, db, 5*time.Second)
+
+	// 分批查询，每次最多1000条，避免 IN 子句过长
+	batchSize := 1000
+	for i := 0; i < len(ids); i += batchSize {
+		end := i + batchSize
+		if end > len(ids) {
+			end = len(ids)
+		}
+
+		var batch []T
+		if err := query.Where(fieldName+" IN ?", ids[i:end]).Find(&batch).Error; err != nil {
+			return nil, err
+		}
+		results = append(results, batch...)
+	}
+
+	return results, nil
+}
+
+// CountWithTimeout 带超时的计数查询
+func CountWithTimeout(ctx context.Context, db *gorm.DB, model interface{}, timeout time.Duration) (int64, error) {
+	var count int64
+	query := WithContext(ctx, db, timeout)
+	err := query.Model(model).Count(&count).Error
+	return count, err
+}
+
+// ExistsOptimized 优化的存在性检查
+func ExistsOptimized(ctx context.Context, db *gorm.DB, model interface{}, condition interface{}, args ...interface{}) (bool, error) {
+	var count int64
+	query := WithContext(ctx, db, 3*time.Second)
+
+	// 使用 SELECT 1 优化，不需要查询所有字段
+	err := query.Model(model).Select("1").Where(condition, args...).Limit(1).Count(&count).Error
+	if err != nil {
+		return false, err
+	}
+
+	return count > 0, nil
+}
+
+// UpdateOptimized 优化的更新操作
+func UpdateOptimized(ctx context.Context, db *gorm.DB, model interface{}, updates map[string]interface{}) error {
+	query := WithContext(ctx, db, 3*time.Second)
+	return query.Model(model).Updates(updates).Error
+}
+
+// BulkInsert 批量插入优化
+func BulkInsert[T any](ctx context.Context, db *gorm.DB, records []T, batchSize int) error {
+	if len(records) == 0 {
+		return nil
+	}
+
+	query := WithContext(ctx, db, 10*time.Second)
+
+	// 使用 CreateInBatches 分批插入
+	if batchSize <= 0 {
+		batchSize = 100
+	}
+
+	return query.CreateInBatches(records, batchSize).Error
+}
+
+// TransactionWithTimeout 带超时的事务
+func TransactionWithTimeout(ctx context.Context, db *gorm.DB, timeout time.Duration, fn func(*gorm.DB) error) error {
+	query := WithContext(ctx, db, timeout)
+	return query.Transaction(fn)
+}