Add Daily sales

internal/repository/orders/order.go

@@ -199,3 +199,32 @@ func (r *OrderRepository) SumAmount(ctx mycontext.Context, req entity.OrderSearc
 
 	return amount, nil
 }
+
+func (r *OrderRepository) GetDailySalesMetrics(ctx context.Context, req entity.OrderSearch) ([]entity.ProductDailySales, error) {
+	var sales []entity.ProductDailySales
+
+	// Build the query with GORM
+	query := r.db.WithContext(ctx).
+		Table("orders o").
+		Select(`DATE_TRUNC('day', o.created_at) AS day, oi.item_id, SUM(oi.qty) AS total_quantity`).
+		Joins("LEFT JOIN order_items oi ON o.id = oi.order_id").
+		Where("o.status = ?", "PAID").
+		Where("o.created_at >= ?", time.Now().AddDate(0, 0, -30)). // Last 30 days
+		Group("day, oi.item_id").
+		Order("day")
+
+	// Apply filters based on the presence of PartnerID and SiteID
+	if req.PartnerID != nil {
+		query = query.Where("o.partner_id = ?", *req.PartnerID)
+	}
+	if req.SiteID != nil {
+		query = query.Where("o.site_id = ?", *req.SiteID)
+	}
+
+	// Execute the query and scan the results
+	if err := query.Find(&sales).Error; err != nil {
+		return nil, err
+	}
+
+	return sales, nil
+}