第 4 阶段：订单、交接与账务--ok

backend/internal/modules/order/handler.go

@@ -145,6 +145,46 @@ func (h *Handler) HandoffRecords(c *gin.Context) {
 	response.OK(c, gin.H{"items": items})
 }
 
+func (h *Handler) SubmitReturn(c *gin.Context) {
+	userID, ok := currentUserID(c)
+	if !ok {
+		response.Unauthorized(c, "缺少用户上下文")
+		return
+	}
+	id, ok := parseID(c)
+	if !ok {
+		return
+	}
+	var req SubmitReturnRequest
+	if err := c.ShouldBindJSON(&req); err != nil {
+		response.BadRequest(c, "归还说明不能为空")
+		return
+	}
+	record, err := h.service.SubmitReturn(userID, id, req)
+	if err != nil {
+		writeOrderError(c, err)
+		return
+	}
+	response.Created(c, record)
+}
+
+func (h *Handler) ConfirmReturn(c *gin.Context) {
+	userID, ok := currentUserID(c)
+	if !ok {
+		response.Unauthorized(c, "缺少用户上下文")
+		return
+	}
+	id, ok := parseID(c)
+	if !ok {
+		return
+	}
+	if err := h.service.ConfirmReturn(userID, id); err != nil {
+		writeOrderError(c, err)
+		return
+	}
+	response.OK(c, gin.H{"completed": true})
+}
+
 func currentUserID(c *gin.Context) (uint64, bool) {
 	value, ok := c.Get(middleware.ContextUserID)
 	if !ok {
@@ -179,6 +219,10 @@ func writeOrderError(c *gin.Context, err error) {
 		response.Error(c, http.StatusConflict, "order_cannot_handoff", "当前订单不能交接")
 	case errors.Is(err, ErrOrderCannotReceive):
 		response.Error(c, http.StatusConflict, "order_cannot_receive", "当前订单不能确认收号")
+	case errors.Is(err, ErrOrderCannotReturn):
+		response.Error(c, http.StatusConflict, "order_cannot_return", "当前订单不能归还")
+	case errors.Is(err, ErrOrderCannotComplete):
+		response.Error(c, http.StatusConflict, "order_cannot_complete", "当前订单不能完成")
 	case errors.Is(err, ErrPermissionDenied):
 		response.Error(c, http.StatusForbidden, "permission_denied", "无权操作该订单")
 	case IsNotFound(err):