优化彩金池累加计算方式

server/app/api/logic/PlayStartLogic.php

@@ -101,7 +101,7 @@ class PlayStartLogic
             }
             $maxRewardRetry = count($tierRewards);
             for ($attempt = 0; $attempt < $maxRewardRetry; $attempt++) {
-                $chosen = $tierRewards[array_rand($tierRewards)];
+                $chosen = self::drawRewardByWeight($tierRewards);
                 $chosenId = (int) ($chosen['id'] ?? 0);
                 if ($direction === 0) {
                     $startCandidates = DiceRewardConfig::getCachedBySEndIndex($chosenId);
@@ -246,10 +246,10 @@ class PlayStartLogic
 
                 $p->save();
 
-                // 彩金池盈利累加：每局累加 (100 - 本局总 real_ev)，其中本局总 real_ev = 普通档位 real_ev + BIGWIN.real_ev（如触发）
+                // 彩金池盈利：每局扣除本局发放的真实成本（普通档位 real_ev + BIGWIN.real_ev 如触发），不额外加 100
                 // 需确保表有 profit_amount 字段（见 db/dice_lottery_config_add_profit_amount.sql）
                 $totalRealEv = $realEv + $bigWinRealEv;
-                $addProfit = 100 - $totalRealEv;
+                $addProfit = -$totalRealEv;
                 try {
                     DiceLotteryPoolConfig::where('id', $configId)->update([
                         'profit_amount' => Db::raw('IFNULL(profit_amount,0) + ' . (float) $addProfit),
@@ -322,6 +322,36 @@ class PlayStartLogic
         return $arr;
     }
 
+    /**
+     * T1-T5 档位内按 DiceRewardConfig.weight 抽取一条配置；权重均为 0 或未设时等权随机
+     * @param array<int, array> $rewards 该档位配置列表（每条含 weight、id、real_ev 等）
+     * @return array 抽中的一条配置
+     */
+    private static function drawRewardByWeight(array $rewards): array
+    {
+        if (empty($rewards)) {
+            throw new \InvalidArgumentException('rewards 不能为空');
+        }
+        $weights = [];
+        foreach ($rewards as $i => $row) {
+            $w = isset($row['weight']) ? max(0, (float) $row['weight']) : 0;
+            $weights[$i] = $w;
+        }
+        $total = array_sum($weights);
+        if ($total <= 0) {
+            return $rewards[array_rand($rewards)];
+        }
+        $r = mt_rand(1, (int) $total);
+        $acc = 0;
+        foreach ($weights as $i => $w) {
+            $acc += $w;
+            if ($r <= $acc) {
+                return $rewards[$i];
+            }
+        }
+        return $rewards[array_key_last($rewards)];
+    }
+
     /**
      * 根据摇取点数（5-30）生成 5 个色子数组，每个 1-6，总和为 $sum
      * @return int[] 如 [1,2,3,4,5]