1 files changed, 21 insertions, 0 deletions
diff --git a/packages/asset-buyer/src/utils/order_utils.ts b/packages/asset-buyer/src/utils/order_utils.ts
new file mode 100644
index 000000000..bb0bdb80f
--- /dev/null
+++ b/packages/asset-buyer/src/utils/order_utils.ts
@@ -0,0 +1,21 @@
+import { SignedOrder } from '@0xproject/types';
+import { BigNumber } from '@0xproject/utils';
+
+import { constants } from '../constants';
+
+export const orderUtils = {
+    isOrderExpired(order: SignedOrder): boolean {
+        const millisecondsInSecond = 1000;
+        const currentUnixTimestampSec = new BigNumber(Date.now() / millisecondsInSecond).round();
+        return order.expirationTimeSeconds.lessThan(currentUnixTimestampSec);
+    },
+    calculateRemainingMakerAssetAmount(order: SignedOrder, remainingTakerAssetAmount: BigNumber): BigNumber {
+        const result = remainingTakerAssetAmount.eq(0)
+            ? constants.ZERO_AMOUNT
+            : remainingTakerAssetAmount.times(order.makerAssetAmount).dividedToIntegerBy(order.takerAssetAmount);
+        return result;
+    },
+    isOpenOrder(order: SignedOrder): boolean {
+        return order.takerAddress === constants.NULL_ADDRESS;
+    },
+};