chore: add quantity stat

backend/gestion/handlers/stats.go

@@ -147,6 +147,76 @@ func GetAdminStats(c *gin.Context) {
 		}
 	}
 
+	// ── Répartition des doses/quantités par produit ───────────────────────────
+	var qtyRows []models.QuantityBreakdownRow
+	gdb.Raw(`
+		SELECT
+			ci.product_id,
+			ci.produit                           AS product_name,
+			ci.quantite                          AS quantity,
+			COUNT(DISTINCT ci.command_id)        AS order_count,
+			SUM(ci.quantite)                     AS total_sold,
+			SUM(ci.prix * ci.quantite)           AS revenue,
+			COALESCE(cat.color, '#7c3aed')       AS category_color
+		FROM command_items ci
+		JOIN commandes c ON c.id = ci.command_id
+		LEFT JOIN products p   ON p.id = ci.product_id
+		LEFT JOIN categories cat ON cat.name = p.category
+		WHERE c.status != 'cancelled'
+		GROUP BY ci.product_id, ci.produit, ci.quantite, cat.color
+		ORDER BY ci.product_id, COUNT(DISTINCT ci.command_id) DESC
+	`).Scan(&qtyRows)
+
+	type productGroup struct {
+		ProductID     int
+		Name          string
+		CategoryColor string
+		TotalOrders   int
+		Quantities    []gin.H
+	}
+	var groups []productGroup
+	groupIdx := map[int]int{}
+	for _, r := range qtyRows {
+		idx, ok := groupIdx[r.ProductID]
+		if !ok {
+			idx = len(groups)
+			groups = append(groups, productGroup{
+				ProductID:     r.ProductID,
+				Name:          r.ProductName,
+				CategoryColor: r.CategoryColor,
+			})
+			groupIdx[r.ProductID] = idx
+		}
+		groups[idx].TotalOrders += r.OrderCount
+		groups[idx].Quantities = append(groups[idx].Quantities, gin.H{
+			"quantity":    r.Quantity,
+			"order_count": r.OrderCount,
+			"total_sold":  r.TotalSold,
+			"revenue":     r.Revenue,
+		})
+	}
+	// Trier par total de commandes décroissant, garder 15 max
+	for i := 0; i < len(groups)-1; i++ {
+		for j := i + 1; j < len(groups); j++ {
+			if groups[j].TotalOrders > groups[i].TotalOrders {
+				groups[i], groups[j] = groups[j], groups[i]
+			}
+		}
+	}
+	if len(groups) > 15 {
+		groups = groups[:15]
+	}
+	byQuantity := make([]gin.H, len(groups))
+	for i, g := range groups {
+		byQuantity[i] = gin.H{
+			"product_id":     g.ProductID,
+			"name":           g.Name,
+			"category_color": g.CategoryColor,
+			"total_orders":   g.TotalOrders,
+			"quantities":     g.Quantities,
+		}
+	}
+
 	// ── Résumé global ─────────────────────────────────────────────────────────
 	var totalOrders int64
 	var totalRevenue float64
@@ -180,10 +250,11 @@ func GetAdminStats(c *gin.Context) {
 			"top_product":   topProductName,
 			"avg_per_day":   avgPerDay,
 		},
-		"by_weekday":    byWeekday,
-		"by_day_30":     byDay,
+		"by_weekday":     byWeekday,
+		"by_day_30":      byDay,
 		"by_day_revenue": byDayRevenue,
 		"by_hour":        byHour,
-		"top_products":  topProducts,
+		"top_products":   topProducts,
+		"by_quantity":    byQuantity,
 	})
 }