1 files changed, 63 insertions, 11 deletions
diff --git a/packages/instant/src/redux/reducer.ts b/packages/instant/src/redux/reducer.ts
index 1538621a5..614ed21ac 100644
--- a/packages/instant/src/redux/reducer.ts
+++ b/packages/instant/src/redux/reducer.ts
@@ -1,11 +1,21 @@
 import { AssetBuyer, BuyQuote } from '@0x/asset-buyer';
-import { ObjectMap } from '@0x/types';
+import { AssetProxyId, ObjectMap } from '@0x/types';
 import { BigNumber } from '@0x/utils';
+import { Web3Wrapper } from '@0x/web3-wrapper';
 import * as _ from 'lodash';
 
 import { assetMetaDataMap } from '../data/asset_meta_data_map';
-import { Asset, AssetMetaData, AsyncProcessState, DisplayStatus, Network } from '../types';
+import {
+    Asset,
+    AssetMetaData,
+    AsyncProcessState,
+    DisplayStatus,
+    Network,
+    OrderProcessState,
+    OrderState,
+} from '../types';
 import { assetUtils } from '../util/asset';
+import { BigNumberInput } from '../util/big_number_input';
 
 import { Action, ActionTypes } from './actions';
 
@@ -14,8 +24,8 @@ export interface State {
     assetBuyer?: AssetBuyer;
     assetMetaDataMap: ObjectMap<AssetMetaData>;
     selectedAsset?: Asset;
-    selectedAssetAmount?: BigNumber;
-    buyOrderState: AsyncProcessState;
+    selectedAssetAmount?: BigNumberInput;
+    buyOrderState: OrderState;
     ethUsdPrice?: BigNumber;
     latestBuyQuote?: BuyQuote;
     quoteRequestState: AsyncProcessState;
@@ -27,7 +37,7 @@ export const INITIAL_STATE: State = {
     network: Network.Mainnet,
     selectedAssetAmount: undefined,
     assetMetaDataMap,
-    buyOrderState: AsyncProcessState.NONE,
+    buyOrderState: { processState: OrderProcessState.NONE },
     ethUsdPrice: undefined,
     latestBuyQuote: undefined,
     latestError: undefined,
@@ -48,11 +58,19 @@ export const reducer = (state: State = INITIAL_STATE, action: Action): State =>
                 selectedAssetAmount: action.data,
             };
         case ActionTypes.UPDATE_LATEST_BUY_QUOTE:
-            return {
-                ...state,
-                latestBuyQuote: action.data,
-                quoteRequestState: AsyncProcessState.SUCCESS,
-            };
+            const newBuyQuoteIfExists = action.data;
+            const shouldUpdate =
+                _.isUndefined(newBuyQuoteIfExists) || doesBuyQuoteMatchState(newBuyQuoteIfExists, state);
+            if (shouldUpdate) {
+                return {
+                    ...state,
+                    latestBuyQuote: newBuyQuoteIfExists,
+                    quoteRequestState: AsyncProcessState.SUCCESS,
+                };
+            } else {
+                return state;
+            }
+
         case ActionTypes.SET_QUOTE_REQUEST_STATE_PENDING:
             return {
                 ...state,
@@ -65,7 +83,7 @@ export const reducer = (state: State = INITIAL_STATE, action: Action): State =>
                 latestBuyQuote: undefined,
                 quoteRequestState: AsyncProcessState.FAILURE,
             };
-        case ActionTypes.UPDATE_SELECTED_ASSET_BUY_STATE:
+        case ActionTypes.UPDATE_BUY_ORDER_STATE:
             return {
                 ...state,
                 buyOrderState: action.data,
@@ -101,7 +119,41 @@ export const reducer = (state: State = INITIAL_STATE, action: Action): State =>
                 ...state,
                 selectedAsset: newSelectedAsset,
             };
+        case ActionTypes.RESET_AMOUNT:
+            return {
+                ...state,
+                latestBuyQuote: undefined,
+                quoteRequestState: AsyncProcessState.NONE,
+                buyOrderState: { processState: OrderProcessState.NONE },
+                selectedAssetAmount: undefined,
+            };
         default:
             return state;
     }
 };
+
+const doesBuyQuoteMatchState = (buyQuote: BuyQuote, state: State): boolean => {
+    const selectedAssetIfExists = state.selectedAsset;
+    const selectedAssetAmountIfExists = state.selectedAssetAmount;
+    // if no selectedAsset or selectedAssetAmount exists on the current state, return false
+    if (_.isUndefined(selectedAssetIfExists) || _.isUndefined(selectedAssetAmountIfExists)) {
+        return false;
+    }
+    // if buyQuote's assetData does not match that of the current selected asset, return false
+    if (selectedAssetIfExists.assetData !== buyQuote.assetData) {
+        return false;
+    }
+    // if ERC20 and buyQuote's assetBuyAmount does not match selectedAssetAmount, return false
+    // if ERC721, return true
+    const selectedAssetMetaData = selectedAssetIfExists.metaData;
+    if (selectedAssetMetaData.assetProxyId === AssetProxyId.ERC20) {
+        const selectedAssetAmountBaseUnits = Web3Wrapper.toBaseUnitAmount(
+            selectedAssetAmountIfExists,
+            selectedAssetMetaData.decimals,
+        );
+        const doesAssetAmountMatch = selectedAssetAmountBaseUnits.eq(buyQuote.assetBuyAmount);
+        return doesAssetAmountMatch;
+    } else {
+        return true;
+    }
+};