Reprice listed goods; honeypot stays at 1%

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

src/Decentralized.Domain/BmSales.cs

@@ -14,6 +14,8 @@ namespace Decentralized.Domain
         public double Health;
         /// <summary>标价倍率与标价（信用点）。</summary>
         public double Mult;
+        /// <summary>参考价：改价时按它重算标价。</summary>
+        public long Ref;
         public int ListPrice;
         public int ListedDay, PayDay;
         public SaleState State = SaleState.Listed;
@@ -71,11 +73,31 @@ namespace Decentralized.Domain
             double share = total > 0 ? Math.Min(1, ListFee(listPrice) / total) : 0;
             w.Taint -= w.Taint * share; w.Basis -= w.Basis * share;
             w.Add(feeAsset, -qty);
-            var s = new BmSale { Item = item, Model = model, FakeOf = fakeOf, Health = health, Mult = m, ListPrice = listPrice, ListedDay = day };
+            var s = new BmSale { Item = item, Model = model, FakeOf = fakeOf, Health = health, Ref = refValue, Mult = m, ListPrice = listPrice, ListedDay = day };
             Sales.Add(s);
             return s;
         }
 
+        public static int RepriceFee(int newPrice) => (int)Math.Ceiling(newPrice * Tuning.BmRepriceFee);
+
+        /// <summary>改价：上架中的货换一个倍率，按参考价重算标价，收改价费；不改变上架日。</summary>
+        public bool Reprice(BmSale s, double m, Wallet w, string feeAsset, int day, Func<string, double> price)
+        {
+            if (s == null || s.State != SaleState.Listed || s.Ref <= 0 || Math.Abs(m - s.Mult) < 1e-9 || m < Tuning.BmSellMin - 1e-9 || m > Tuning.BmSellMax + 1e-9 || Closed(day) || feeAsset == Assets.CRC) return false;
+            int listPrice = ListPriceOf(s.Ref, m);
+            double p = price(feeAsset);
+            if (p <= 0) return false;
+            int fee = RepriceFee(listPrice);
+            double qty = fee / p;
+            if (w.Avail(feeAsset) + 1e-9 < qty) return false;
+            double total = w.Value(price);
+            double share = total > 0 ? Math.Min(1, fee / total) : 0;
+            w.Taint -= w.Taint * share; w.Basis -= w.Basis * share;
+            w.Add(feeAsset, -qty);
+            s.Mult = m; s.ListPrice = listPrice;
+            return true;
+        }
+
         public void Delist(BmSale s) { s.State = SaleState.Delisted; s.Why = "delist"; }
 
         /// <summary>未到账的货款（信用点）：跑路时一并归零，也推高跑路概率。</summary>