[库存][修改]:库存只能同增，同减

mallinkService/src/main/java/com/iformall/service/impl/WxCouponServiceImpl.java

@@ -293,6 +293,18 @@ public class WxCouponServiceImpl implements WxCouponService {
             wxCouponMapper.insertSelective(record);
 
         } else {
+            if(record.getInventory() != null && record.getRemainInventory() != null) {
+                // 库存修改检查
+                WxCoupon oldCoupon = wxCouponMapper.selectByPrimaryKey(record.getId());
+                if(oldCoupon.getRemainInventory() == record.getRemainInventory()) {
+                    // 库存未变, 不更新库存
+                    record.setRemainInventory(null);
+                    record.setInventory(null);
+                } else {
+                    // 库存增加，要同时增加, 库存减少，要同时减少
+                    record.setInventory(oldCoupon.getInventory() + record.getRemainInventory() - oldCoupon.getRemainInventory());
+                }
+            }
             if (merchantParamList != null && merchantParamList.size() > 0) {
                 WxCouponMerchant cmParam = new WxCouponMerchant();
                 cmParam.setProductId(record.getId());