From 2b18549f021271195091abc270dbf2b0eb2c5b9f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Adrian=20Z=C3=BCrcher?= <zuercher@mst.local>
Date: Wed, 29 Oct 2025 22:14:07 +0100
Subject: [PATCH] fix exist function for array of values and error handling
 delete

---
 dbHandler.go | 48 +++++++++++++++++++++++++++++-------------------
 1 file changed, 29 insertions(+), 19 deletions(-)

diff --git a/dbHandler.go b/dbHandler.go
index 619336f..9547300 100644
--- a/dbHandler.go
+++ b/dbHandler.go
@@ -245,13 +245,14 @@ func (dH *DBHandler) DeleteById(model any, ids ...uint) error {
 	}
 
 	dH.logger.Debug("deleteById", "delete ids "+fmt.Sprint(ids))
+	err := dH.Exists(model, "id", ids, false)
 
 	// Always use Model() to avoid GORM’s “limit 1” safeguard
 	if err := dH.db.Model(model).Where("id IN ?", ids).Delete(nil).Error; err != nil {
 		return fmt.Errorf("delete failed: %w", err)
 	}
 
-	return nil
+	return err
 }
 
 // deleteByKey
@@ -301,33 +302,42 @@ func (dH *DBHandler) DeleteByKey(model any, key string, value any, LikeSearch bo
 //
 // Returns:
 //   - error: “no record found” or DB error.
-func (dH *DBHandler) Exists(model any, key string, value any, likeSearch bool) (err error) {
+func (dH *DBHandler) Exists(model any, key string, value any, likeSearch bool) error {
 	var query string
+	var args any
 
-	switch v := value.(type) {
-	case []string, []int, []uint, []int64, []uint64, []float64:
-		// Handle slice case — use IN clause
-		query = fmt.Sprintf("%s IN ?", key)
-	case string:
-		if likeSearch {
-			v = strings.ReplaceAll(v, "*", "%")
-			query = fmt.Sprintf("%s LIKE ?", key)
-			value = v
-		} else {
-			query = fmt.Sprintf("%s = ?", key)
+	// Detect LIKE and IN behavior
+	val := reflect.ValueOf(value)
+	isSlice := val.Kind() == reflect.Slice
+
+	switch {
+	case isSlice:
+		if val.Len() == 0 {
+			return fmt.Errorf("empty slice for %s", key)
 		}
+		query = fmt.Sprintf("%s IN ?", key)
+		args = value
+
+	case likeSearch:
+		str := strings.ReplaceAll(fmt.Sprint(value), "*", "%")
+		query = fmt.Sprintf("%s LIKE ?", key)
+		args = str
+
 	default:
-		// Handle any other single value (numbers, bools, etc.)
 		query = fmt.Sprintf("%s = ?", key)
+		args = value
 	}
 
-	dH.logger.Debug("exists", "check if exists key "+query+" value "+fmt.Sprint(value))
+	dH.logger.Debug("exists", "checking existence for key "+query+" value "+fmt.Sprint(args))
 
-	err = dH.db.Where(query, value).First(model).Error
-	if errors.Is(err, gorm.ErrRecordNotFound) {
+	var count int64
+	tx := dH.db.Model(model).Where(query, args).Count(&count)
+	if tx.Error != nil {
+		return fmt.Errorf("query failed: %w", tx.Error)
+	}
+
+	if count == 0 {
 		return fmt.Errorf("no record found for %s %v", key, value)
-	} else if err != nil {
-		return fmt.Errorf("query failed: %w", err)
 	}
 
 	return nil