fix(order): multiply draft weight by product count

core/components/minishop3/src/Controllers/Api/Manager/OrdersController.php

@@ -1396,21 +1396,15 @@ public function deleteProduct(array $params = []): array
      */
     protected function recalculateOrderTotals(msOrder $order): void
     {
-        $cartCost = 0;
-        $weight = 0;
-
         $products = $this->modx->getIterator(\MiniShop3\Model\msOrderProduct::class, [
             'order_id' => $order->get('id'),
         ]);
-
-        foreach ($products as $product) {
-            $cartCost += (float)$product->get('cost');
-            $weight += (float)$product->get('weight') * (int)$product->get('count');
-        }
+        $totals = OrderService::aggregateProductsTotals($products);
+        $cartCost = $totals['cart_cost'];
+        $weight = $totals['weight'];
 
         $order->set('cart_cost', $cartCost);
         $order->set('weight', $weight);
-
         // Recalculate total cost (cart + delivery; payment deltas are reflected in cost when persisted elsewhere)
         /** @var OrderService $orderService */
         $orderService = $this->modx->services->get('ms3_order_service');

core/components/minishop3/src/Services/Order/ManagerOrderCostRecalculator.php

@@ -48,22 +48,11 @@ public function __construct(modX $modx, MiniShop3 $ms3)
      */
     public function calculateProductTotals(msOrder $order): array
     {
-        $cartCost = 0.0;
-        $weight = 0.0;
-
         $products = $this->modx->getIterator(msOrderProduct::class, [
             'order_id' => $order->get('id'),
         ]);
 
-        foreach ($products as $product) {
-            $cartCost += (float)$product->get('cost');
-            $weight += (float)$product->get('weight') * (int)$product->get('count');
-        }
-
-        return [
-            'cart_cost' => round($cartCost, 6),
-            'weight' => round($weight, 6),
-        ];
+        return OrderService::aggregateProductsTotals($products);
     }
 
     /**

core/components/minishop3/src/Services/Order/OrderCostCalculator.php

@@ -227,6 +227,17 @@ public function getTotalCost(
         string $ctx = 'web',
         bool $onlyCost = false
     ): array {
+        $before = $this->ms3->utils->invokeEvent('msOnBeforeGetOrderCost', [
+            'calculator' => $this,
+            'cart' => $this->ms3->cart,
+            'draft' => $draft,
+            'with_cart' => true,
+            'only_cost' => $onlyCost,
+        ]);
+        if (!$before['success']) {
+            return $this->error($before['message']);
+        }
+
         $cartCostResponse = $this->getCartCost($draft, $token, $ctx);
         $cartCost = $cartCostResponse['success'] ? $cartCostResponse['data']['cost'] : 0;
 
@@ -245,6 +256,27 @@ public function getTotalCost(
             (float) $paymentCost
         );
 
+        $after = $this->ms3->utils->invokeEvent('msOnGetOrderCost', [
+            'calculator' => $this,
+            'cart' => $this->ms3->cart,
+            'draft' => $draft,
+            'with_cart' => true,
+            'only_cost' => $onlyCost,
+            'cost' => $cost,
+            'cart_cost' => $cartCost,
+            'delivery_cost' => $deliveryCost,
+            'payment_cost' => $paymentCost,
+        ]);
+        if (!$after['success']) {
+            return $this->error($after['message']);
+        }
+
+        $cost = (float) ($after['data']['cost'] ?? $cost);
+        $cartCost = (float) ($after['data']['cart_cost'] ?? $cartCost);
+        $deliveryCost = (float) ($after['data']['delivery_cost'] ?? $deliveryCost);
+        $paymentCost = (float) ($after['data']['payment_cost'] ?? $paymentCost);
+        $cost = $orderService->clampComputedTotal($draft, $cartCost, $deliveryCost, $paymentCost);
+
         if ($onlyCost) {
             return $this->success('ms3_order_getcost_success', ['cost' => $cost]);
         }

core/components/minishop3/src/Services/Order/OrderDraftManager.php

@@ -145,28 +145,23 @@ public function getOrCreateDraft(string $token, string $ctx = 'web', ?int $custo
     }
 
     /**
-     * Recalculate order costs (cart, delivery, total)
+     * Recalculate and persist draft cart_cost / weight / cost from order products.
+     *
+     * Plugin hooks: $draft->save() fires msOnBeforeSaveOrder / msOnSaveOrder (see msOrder::save).
+     * Display-time cost adjustment uses msOnBeforeGetOrderCost / msOnGetOrderCost via OrderCostCalculator,
+     * not this persist path — do not invent a separate "recalculate" event here.
      */
     public function recalculate(msOrder $draft): void
     {
-        // TODO: event before recalculating order
-        $products = $draft->getMany('Products');
-        $cart_cost = 0;
-        $weight = 0;
-
-        if (!empty($products)) {
-            foreach ($products as $product) {
-                $weight += $product->get('weight');
-                $cart_cost += $product->get('cost');
-            }
-        }
+        $totals = OrderService::aggregateProductsTotals($draft->getMany('Products') ?? []);
+        $cart_cost = $totals['cart_cost'];
+        $weight = $totals['weight'];
 
         /** @var OrderService $orderService */
         $orderService = $this->modx->services->get('ms3_order_service');
         $delivery_cost = (float) $draft->get('delivery_cost');
         $cost = $orderService->clampComputedTotal($draft, (float) $cart_cost, $delivery_cost, 0.0);
 
-        // TODO: event on recalculating order
         $draft->set('updatedon', time());
         $draft->set('cart_cost', $cart_cost);
         $draft->set('cost', $cost);

core/components/minishop3/src/Services/Order/OrderFinalizeService.php

@@ -380,18 +380,12 @@ protected function validateDeliveryRequiredFields(msOrder $order): array
      */
     protected function calculateCosts(msOrder $order): array
     {
-        // Calculate cart cost from order products
-        $cartCost = 0;
-        $weight = 0;
-
         $products = $this->modx->getIterator(msOrderProduct::class, [
             'order_id' => $order->get('id'),
         ]);
-
-        foreach ($products as $product) {
-            $cartCost += (float) $product->get('cost');
-            $weight += (float) $product->get('weight') * (int) $product->get('count');
-        }
+        $totals = OrderService::aggregateProductsTotals($products);
+        $cartCost = $totals['cart_cost'];
+        $weight = $totals['weight'];
 
         // Calculate delivery cost
         $deliveryCost = 0;

core/components/minishop3/src/Services/Order/OrderService.php

@@ -63,6 +63,29 @@ public function clampComputedTotal(
         return 0.0;
     }
 
+    /**
+     * Sum cart_cost and total weight from order product lines.
+     * Weight is unit weight × count (cart status / draft / finalize / manager).
+     *
+     * @param iterable<object> $products Objects with get('weight'|'cost'|'count')
+     * @return array{cart_cost: float, weight: float}
+     */
+    public static function aggregateProductsTotals(iterable $products): array
+    {
+        $cartCost = 0.0;
+        $weight = 0.0;
+
+        foreach ($products as $product) {
+            $cartCost += (float) $product->get('cost');
+            $weight += (float) $product->get('weight') * (int) $product->get('count');
+        }
+
+        return [
+            'cart_cost' => round($cartCost, 6),
+            'weight' => round($weight, 6),
+        ];
+    }
+
     /**
      * Recalculate products in order
      *

core/components/minishop3/tests/OrderDraftWeightTest.php

@@ -0,0 +1,75 @@
+<?php
+
+/**
+ * Regression: draft weight must multiply unit weight by count (#375).
+ *
+ * Run: php tests/OrderDraftWeightTest.php
+ */
+
+declare(strict_types=1);
+
+require __DIR__ . '/../vendor/autoload.php';
+
+use MiniShop3\Services\Order\OrderService;
+
+$fail = static function (string $message): never {
+    fwrite(STDERR, "FAIL: {$message}\n");
+    exit(1);
+};
+
+$assertSame = static function ($expected, $actual, string $label) use ($fail): void {
+    if ($actual !== $expected) {
+        $fail(sprintf(
+            "%s:\nexpected: %s\nactual:   %s",
+            $label,
+            var_export($expected, true),
+            var_export($actual, true)
+        ));
+    }
+};
+
+$product = static function (float $weight, int $count, float $cost = 0.0): object {
+    return new class ($weight, $count, $cost) {
+        public function __construct(
+            private float $weight,
+            private int $count,
+            private float $cost,
+        ) {
+        }
+
+        public function get(string $field): float|int
+        {
+            return match ($field) {
+                'weight' => $this->weight,
+                'count' => $this->count,
+                'cost' => $this->cost,
+                default => 0,
+            };
+        }
+    };
+};
+
+$empty = OrderService::aggregateProductsTotals([]);
+$assertSame(0.0, $empty['weight'], 'empty weight');
+$assertSame(0.0, $empty['cart_cost'], 'empty cart_cost');
+
+$single = OrderService::aggregateProductsTotals([
+    $product(1.0, 3, 30.0),
+]);
+$assertSame(3.0, $single['weight'], 'weight=1 count=3 → total weight 3');
+$assertSame(30.0, $single['cart_cost'], 'line cost is not multiplied again');
+
+$multi = OrderService::aggregateProductsTotals([
+    $product(1.5, 2, 10.0),
+    $product(0.5, 4, 20.0),
+]);
+$assertSame(5.0, $multi['weight'], '1.5*2 + 0.5*4');
+$assertSame(30.0, $multi['cart_cost'], '10 + 20');
+
+// Guard: unit weight alone must not be treated as total (the #375 bug)
+if ($single['weight'] === 1.0) {
+    $fail('weight must include count; got unit weight only');
+}
+
+fwrite(STDOUT, "OK OrderDraftWeightTest\n");
+exit(0);