Automatically fix balances within tolerance, remove unused Uniswap component

Author: mathijs81

web/src/App.vue

@@ -4,7 +4,9 @@
       <div class="container">
         <Menubar :model="items">
           <template #start>
-            <router-link to="/" class="logo"><img src="@/assets/logo.png" class="img-fluid"> TokenBlend</router-link>
+            <router-link to="/" class="logo"
+              ><img src="@/assets/logo.png" class="img-fluid" /> TokenBlend</router-link
+            >
           </template>
         </Menubar>
       </div>
@@ -65,4 +67,4 @@ export default defineComponent({
   width: 2rem;
   height: 2rem;
 }
-</style>
+</style>

web/src/components/OrderPlanDialog.vue

@@ -96,7 +96,15 @@
 
 <script lang="ts">
 import { PlannedOrder, OrderType } from '@/orderplan/orderplan';
-import { bigNumberToFixed, compareBignumber, formatMaxDigits, numberMixin } from '@/util/numbers';
+import {
+  bigNumberToFixed,
+  compareBignumber,
+  fixedToBigNumber,
+  formatMaxDigits,
+  numberMixin,
+  toleranceMin,
+} from '@/util/numbers';
+import { getTokenBalance } from '@/util/tokens';
 import { idleService } from '@/web3/idleService';
 import { ParaSwapPredictedOutput, paraswapService, PredictedOutput } from '@/web3/paraswapService';
 import { TransactionResult, uniswapService } from '@/web3/uniswapService';
@@ -142,6 +150,10 @@ export default defineComponent({
   },
   methods: {
     async calculateBest(order: OrderWithResult) {
+      const address = web3Service.status().address;
+      if (!address) {
+        throw new Error('web3 not initialized yet');
+      }
       const uniswapOption: Option = reactive({
         platform: 'Uniswap',
         inProgress: true,
@@ -151,13 +163,14 @@ export default defineComponent({
         inProgress: true,
       });
       order.options = [uniswapOption, paraswapOption];
+      await this.prepareOrder(order, address);
       const uniswapOutput = uniswapService.getPredictedOutput(order).then((output) => {
-        console.log("output uniswap: " , output);
+        console.log('output uniswap: ', output);
         uniswapOption.inProgress = false;
         uniswapOption.plan = output;
       });
       const paraswapOutput = paraswapService.getPredictedOutput(order).then((output) => {
-        console.log("output paraswap: " , output);
+        console.log('output paraswap: ', output);
         paraswapOption.inProgress = false;
         paraswapOption.plan = output;
       });
@@ -195,6 +208,7 @@ export default defineComponent({
           executeFunction = (order) =>
             idleService.redeemToken(order.fromToken, address, order.sendAmount);
         } else {
+          await this.prepareOrder(order, address);
           if (platform === undefined) {
             // work on a copy so we keep the UI clean
             const copy = { ...order };
@@ -239,7 +253,7 @@ export default defineComponent({
         return '---';
       }
       const fixed = bigNumberToFixed(result, order.toToken.decimals);
-      return order.toToken.symbol + " " + formatMaxDigits(fixed.toUnsafeFloat());
+      return order.toToken.symbol + ' ' + formatMaxDigits(fixed.toUnsafeFloat());
     },
     isSwap(order: PlannedOrder): boolean {
       return order.ordertype == OrderType.SWAP;
@@ -267,6 +281,13 @@ export default defineComponent({
         return name;
       }
     },
+    async prepareOrder(order: PlannedOrder, address: string) {
+      // Make sure that the amount wanted is not higher than our balance
+      const balance = await getTokenBalance(order.fromToken.id, address);
+      const amountBn = fixedToBigNumber(order.sendAmount, order.fromToken.decimals);
+      const newAmount = toleranceMin(amountBn, balance);
+      order.sendAmount = bigNumberToFixed(newAmount, order.fromToken.decimals);
+    },
   },
   mixins: [numberMixin],
 });

web/src/router/index.ts

@@ -3,8 +3,6 @@ import Home from '../views/Home.vue';
 import EnzymeAccount from '../views/EnzymeAccount.vue';
 import WalletAccount from '../views/WalletAccount.vue';
 
-import Uniswap from '../views/Uniswap.vue';
-
 const routes: Array<RouteRecordRaw> = [
   {
     path: '/',
@@ -22,11 +20,6 @@ const routes: Array<RouteRecordRaw> = [
     name: 'WalletAccount',
     component: WalletAccount,
   },
-  {
-    path: '/uniswap',
-    name: 'Uniswap',
-    component: Uniswap,
-  },
 ];
 
 const router = createRouter({

web/src/util/numbers.ts

@@ -14,6 +14,36 @@ function reduceDecimalString(value: string, decimals: number): string {
   return parts[0] + '.' + parts[1].substr(0, decimals);
 }
 
+/**
+ * Make sure amount is lower than balance, as long as it's maximum tolerance x higher.
+ * We frequently try to e.g. sell all tokens and this amount may be dependent on an earlier trade
+ * that may have executed at a less favorable rate than expected.
+ * This will then cause trades to fail because the requested amount is a tiny bit too high, this fixes that.
+ *
+ * The tolerance is there to not just reduce some crazy high amount back to balance, but that we still
+ * get an error then, because probably there's some bug or other problem happening.
+ */
+export function toleranceMin(amount: BigNumber, balance: BigNumber, tolerance = 0.1): BigNumber {
+  if (amount.lte(balance)) {
+    return amount;
+  }
+  // Check if amount is within tolerance
+  const toleranceAmount = fixedToBigNumber(
+    bigNumberToFixed(balance, 18).mulUnsafe(fixedNum(1 + tolerance)),
+    18
+  );
+  if (amount.gt(toleranceAmount)) {
+    throw new Error(`Amount ${amount.toString()} much bigger than balance ${balance.toString()}`);
+  }
+  console.log(
+    `Downwards adjusting number from ${bigNumberToFixed(amount, 18)} to ${bigNumberToFixed(
+      balance,
+      18
+    )}`
+  );
+  return balance;
+}
+
 export function compareFixed(a: FixedNumber, b: FixedNumber): number {
   const bn1 = fixedToBigNumber(a, 18);
   const bn2 = fixedToBigNumber(b, 18);

web/src/views/Home.vue

@@ -1,7 +1,7 @@
 <template>
   <div class="home">
     <div class="hero position-relative text-center p-4">
-      <h1 class="display-1"><img src="@/assets/logo.png"> TokenBlend</h1>
+      <h1 class="display-1"><img src="@/assets/logo.png" /> TokenBlend</h1>
       <h2 class="h2">Asset allocation for your Enzyme funds and Ethereum wallet</h2>
     </div>
   </div>

web/src/views/Uniswap.vue

@@ -1,4 +1,4 @@
-import { bigNumberToFixed, fixedToBigNumber, formatMaxDigits } from '@/util/numbers';
+import { bigNumberToFixed, fixedToBigNumber, formatMaxDigits, toleranceMin } from '@/util/numbers';
 import { StakedToken } from '@/util/stakedTokens';
 import { getTokenAllowance, getTokenBalance, tokenApprove, TokenData } from '@/util/tokens';
 import { BigNumber, Contract, FixedNumber, utils } from 'ethers';
@@ -101,8 +101,11 @@ class IdleService {
       const ok = await tokenApprove(token.id, contractAddress, unlimitedAllowance);
       console.log('token approve: ' + ok);
     }
-    console.log(amountBn, amountBn.toString());
-    const result = await contract.mintIdleToken(amountBn, true, accountAddress);
+
+    const balance = await getTokenBalance(token.id, accountAddress);
+    const finalAmount = toleranceMin(amountBn, balance);
+
+    const result = await contract.mintIdleToken(finalAmount, true, accountAddress);
     console.log(result);
     const receipt = await result.wait();
     console.log(receipt);
@@ -128,16 +131,7 @@ class IdleService {
     let redeemAmount = fixedToBigNumber(amount.divUnsafe(bigNumberToFixed(priceWithFee, 18)), 18);
 
     const balance: BigNumber = await contract.balanceOf(accountAddress);
-    if (redeemAmount.gt(balance)) {
-      // If there's more than 10% difference, throw, otherwise just adjust to maximum
-      if (redeemAmount.sub(balance).gt(redeemAmount.div(10))) {
-        throw new Error(
-          `Tried to redeem ${redeemAmount.toString()} (from ${amount.toString()} original), but balance is ${balance.toString()}`
-        );
-      }
-      console.log('Trying to redeem more than balance, adjusting to redeem max balance');
-      redeemAmount = balance;
-    }
+    redeemAmount = toleranceMin(redeemAmount, balance);
 
     const result = await contract.redeemIdleToken(redeemAmount);
     console.log(result);