退款纠纷分配

backend/internal/modules/dispute/arbitration.go

@@ -5,6 +5,7 @@ import (
 	"errors"
 	"fmt"
 	"log"
+	"math"
 	"time"
 
 	"hfb_sys/backend/internal/listingstatus"
@@ -246,7 +247,11 @@ func buildArbitrationSettlement(order model.RentalOrder, req ArbitrateRequest, r
 		addRenterRefund(req.AmountCent, "仲裁部分退款")
 		// 部分退款为合并金额，无法精确拆分租金/押金，按押金优先归类以便暂扣。
 		settlement.RenterDepositRefundCent = money.MinCent(req.AmountCent, depositAmountCent)
-		addOwnerIncome(money.MinCent(totalCent-req.AmountCent, ownerRentAmountCent+depositAmountCent), "仲裁剩余金额结算给号主")
+		// 号主仅拿「未退租金中的号主份额 + 未退押金」，平台加价按未退租金比例预留，避免整笔剩余进号主。
+		addOwnerIncome(
+			partialRefundOwnerIncomeCent(rentAmountCent, ownerRentAmountCent, depositAmountCent, req.AmountCent),
+			"仲裁剩余金额结算给号主",
+		)
 	case "release_deposit":
 		addOwnerIncome(ownerRentAmountCent, "仲裁确认订单金额结算给号主")
 		addRenterRefund(depositAmountCent, "仲裁释放押金给租客")
@@ -273,6 +278,66 @@ func buildArbitrationSettlement(order model.RentalOrder, req ArbitrateRequest, r
 	return settlement, nil
 }
 
+// partialRefundOwnerIncomeCent 计算部分退款后号主应得。
+// 退款优先冲押金，其余冲租金；未退租金按预收结构拆分：
+// 平台费 = 租客租金 − 号主租金，并按 未退租金/预收租金 比例预留，剩余才归号主。
+// 这样可避免「剩余金额整笔给号主」把平台加价分给用户。
+func partialRefundOwnerIncomeCent(rentAmountCent, ownerRentAmountCent, depositAmountCent, renterRefundCent int64) int64 {
+	if renterRefundCent < 0 {
+		renterRefundCent = 0
+	}
+	totalCent := rentAmountCent + depositAmountCent
+	if renterRefundCent > totalCent {
+		renterRefundCent = totalCent
+	}
+	if ownerRentAmountCent < 0 {
+		ownerRentAmountCent = 0
+	}
+	if ownerRentAmountCent > rentAmountCent {
+		ownerRentAmountCent = rentAmountCent
+	}
+
+	// 退款优先视为押金退还，其余视为租金退还（与 RenterDepositRefundCent 归类一致）
+	depositRefunded := money.MinCent(renterRefundCent, depositAmountCent)
+	rentRefunded := renterRefundCent - depositRefunded
+	rentLeft := rentAmountCent - rentRefunded
+	if rentLeft < 0 {
+		rentLeft = 0
+	}
+	depositLeft := depositAmountCent - depositRefunded
+
+	platformFeeCent := rentAmountCent - ownerRentAmountCent
+	if platformFeeCent < 0 {
+		platformFeeCent = 0
+	}
+
+	// 按未退租金占比预留平台费
+	platformKeepCent := int64(0)
+	if rentAmountCent > 0 && rentLeft > 0 && platformFeeCent > 0 {
+		platformKeepCent = int64(math.Round(float64(platformFeeCent) * float64(rentLeft) / float64(rentAmountCent)))
+		platformKeepCent = money.MinCent(platformKeepCent, rentLeft)
+		platformKeepCent = money.MinCent(platformKeepCent, platformFeeCent)
+	}
+
+	ownerFromRent := rentLeft - platformKeepCent
+	if ownerFromRent > ownerRentAmountCent {
+		ownerFromRent = ownerRentAmountCent
+	}
+	if ownerFromRent < 0 {
+		ownerFromRent = 0
+	}
+
+	ownerIncome := ownerFromRent + depositLeft
+	remaining := totalCent - renterRefundCent
+	if ownerIncome > remaining {
+		ownerIncome = remaining
+	}
+	if ownerIncome < 0 {
+		return 0
+	}
+	return ownerIncome
+}
+
 func (r *Repository) prepareRefund(order *model.RentalOrder, amountCent int64, bizType string, remark string) (*refundAction, error) {
 	if amountCent <= 0 {
 		return nil, nil