From 509ddaeaa0428e7dc7a2772b90a9428c050cb312 Mon Sep 17 00:00:00 2001
From: Chi Kei Chan <chikeichan@gmail.com>
Date: Tue, 23 Oct 2018 15:19:49 -0700
Subject: [PATCH] Implement Add Liquidity  (#77)

* CSS fixes

* Add Liquidity UI and Validation

* Finish Add Liquidity
---
 .../CurrencyInputPanel/currency-panel.scss    |  21 +-
 src/components/CurrencyInputPanel/index.js    |  33 +++-
 src/components/Tab/tab.scss                   |   9 +-
 src/ducks/web3connect.js                      |  47 +++--
 src/index.js                                  |   2 +-
 src/pages/Pool/AddLiquidity.js                | 183 ++++++++++++++++--
 src/variables.scss                            |   1 +
 7 files changed, 242 insertions(+), 54 deletions(-)

diff --git a/src/components/CurrencyInputPanel/currency-panel.scss b/src/components/CurrencyInputPanel/currency-panel.scss
index 73b347bfe4..032e8fdb0a 100644
--- a/src/components/CurrencyInputPanel/currency-panel.scss
+++ b/src/components/CurrencyInputPanel/currency-panel.scss
@@ -2,25 +2,26 @@
 
 .currency-input-panel {
   @extend %col-nowrap;
+  box-shadow: 0 4px 8px 0 rgba($royal-blue, 0.1);
+  position: relative;
+  border-radius: 1.25rem;
+  z-index: 200;
 
   &__container {
-    position: relative;
-    z-index: 200;
     border-radius: 1.25rem;
-    border: 0.5px solid $mercury-gray;
+    box-shadow: 0 0 0 .5px $mercury-gray;
     background-color: $white;
-    box-shadow: 0px 4px 4px 2px rgba($royal-blue, 0.05);
 
     &--error {
-      border: 0.5px solid $salmon-red;
+      box-shadow: 0 0 0 .5px $salmon-red;
     }
 
     &:focus-within {
-      border-color: $royal-blue;
+      box-shadow: 0 0 .5px .5px $malibu-blue;
     }
 
     &--error:focus-within {
-      border-color: $salmon-red;
+      box-shadow: 0 0 .5px .5px $salmon-red;
     }
   }
 
@@ -93,6 +94,12 @@
         background-image: url(../../assets/images/dropdown.svg);
       }
     }
+
+    &--disabled {
+      .currency-input-panel__dropdown-icon {
+        opacity: 0;
+      }
+    }
   }
 
   &__sub-currency-select {
diff --git a/src/components/CurrencyInputPanel/index.js b/src/components/CurrencyInputPanel/index.js
index d8d0f08e78..89d8aed821 100644
--- a/src/components/CurrencyInputPanel/index.js
+++ b/src/components/CurrencyInputPanel/index.js
@@ -45,10 +45,13 @@ class CurrencyInputPanel extends Component {
     selectedTokens: PropTypes.array.isRequired,
     errorMessage: PropTypes.string,
     selectedTokenAddress: PropTypes.string,
+    disableTokenSelect: PropTypes.bool,
+    filteredTokens: PropTypes.arrayOf(PropTypes.string),
   };
 
   static defaultProps = {
     selectedTokens: [],
+    filteredTokens: [],
     onCurrencySelected() {},
     onValueChange() {},
     selectedTokenAddress: '',
@@ -64,19 +67,20 @@ class CurrencyInputPanel extends Component {
   };
 
   createTokenList = () => {
+    const { filteredTokens } = this.props;
     let tokens = this.props.tokenAddresses.addresses;
     let tokenList = [ { value: 'ETH', label: 'ETH', address: 'ETH' } ];
 
     for (let i = 0; i < tokens.length; i++) {
-      let entry = { value: '', label: '' };
-      entry.value = tokens[i][0];
-      entry.label = tokens[i][0];
-      entry.address = tokens[i][1];
-      tokenList.push(entry);
-      TOKEN_ADDRESS_TO_LABEL[tokens[i][1]] = tokens[i][0];
+        let entry = { value: '', label: '' };
+        entry.value = tokens[i][0];
+        entry.label = tokens[i][0];
+        entry.address = tokens[i][1];
+        tokenList.push(entry);
+        TOKEN_ADDRESS_TO_LABEL[tokens[i][1]] = tokens[i][0];
     }
 
-    return tokenList;
+    return tokenList.filter(({ address }) => !filteredTokens.includes(address));
   };
 
   onTokenSelect = (address) => {
@@ -122,7 +126,12 @@ class CurrencyInputPanel extends Component {
   renderTokenList() {
     const tokens = this.createTokenList();
     const { searchQuery } = this.state;
-    const { selectedTokens } = this.props;
+    const { selectedTokens, disableTokenSelect } = this.props;
+
+    if (disableTokenSelect) {
+      return;
+    }
+
     let results;
 
     if (!searchQuery) {
@@ -196,6 +205,7 @@ class CurrencyInputPanel extends Component {
       value,
       onValueChange,
       selectedTokenAddress,
+      disableTokenSelect,
     } = this.props;
 
     return (
@@ -232,8 +242,13 @@ class CurrencyInputPanel extends Component {
             <button
               className={classnames("currency-input-panel__currency-select", {
                 'currency-input-panel__currency-select--selected': selectedTokenAddress,
+                'currency-input-panel__currency-select--disabled': disableTokenSelect,
               })}
-              onClick={() => this.setState({ isShowingModal: true })}
+              onClick={() => {
+                if (!disableTokenSelect) {
+                  this.setState({ isShowingModal: true });
+                }
+              }}
             >
               {
                 selectedTokenAddress
diff --git a/src/components/Tab/tab.scss b/src/components/Tab/tab.scss
index 65e8422836..0f71c608c8 100644
--- a/src/components/Tab/tab.scss
+++ b/src/components/Tab/tab.scss
@@ -6,14 +6,14 @@
   height: 3rem;
   background-color: $concrete-gray;
   border-radius: 3rem;
-  border: 1px solid $mercury-gray;
+  box-shadow: 0 0 0 .5px darken($concrete-gray, 5);
 
   .tab:first-child {
-    margin-left: -1px;
+    //margin-left: -1px;
   }
 
   .tab:last-child {
-    margin-right: -1px;
+    //margin-right: -1px;
   }
 }
 
@@ -24,7 +24,6 @@
   height: 3rem;
   flex: 1 0 auto;
   border-radius: 3rem;
-  border: 1px solid transparent;
   transition: 300ms ease-in-out;
   cursor: pointer;
 
@@ -36,7 +35,7 @@
   &--selected {
     background-color: $white;
     border-radius: 3rem;
-    border: 1px solid $mercury-gray;
+    box-shadow: 0 0 .5px .5px $mercury-gray;
     font-weight: 500;
 
     span {
diff --git a/src/ducks/web3connect.js b/src/ducks/web3connect.js
index d42ca4ab17..0fead1803f 100644
--- a/src/ducks/web3connect.js
+++ b/src/ducks/web3connect.js
@@ -17,6 +17,7 @@ export const ADD_CONTRACT = 'web3connect/addContract';
 
 const initialState = {
   web3: null,
+  initialized: false,
   account: '',
   balances: {
     ethereum: {},
@@ -39,7 +40,7 @@ export const selectors = () => (dispatch, getState) => {
   return {
     getBalance: address => {
       const balance = state.balances.ethereum[address];
-      console.log({balance})
+
       if (!balance) {
         dispatch(watchBalance({ balanceOf: address }));
         return Balance(0, 'ETH');
@@ -98,7 +99,6 @@ export const initialize = () => (dispatch, getState) => {
 
     if (typeof window.web3 !== 'undefined') {
       const web3 = new Web3(window.web3.currentProvider);
-      await window.ethereum.enable();
       dispatch({
         type: INITIALIZE,
         payload: web3,
@@ -108,28 +108,38 @@ export const initialize = () => (dispatch, getState) => {
   })
 };
 
-export const watchBalance = ({ balanceOf, tokenAddress }) => {
+export const watchBalance = ({ balanceOf, tokenAddress }) => (dispatch, getState) => {
   if (!balanceOf) {
-    return { type: '' };
+    return;
   }
 
+  const { web3connect } = getState();
+  const { watched } = web3connect;
+
   if (!tokenAddress) {
-    return {
+    if (watched.balances.ethereum.includes(balanceOf)) {
+      return;
+    }
+    dispatch({
       type: WATCH_ETH_BALANCE,
       payload: balanceOf,
-    };
+    });
   } else if (tokenAddress) {
-    return {
+    if (watched.balances[tokenAddress] && watched.balances[tokenAddress].includes(balanceOf)) {
+      return;
+    }
+    dispatch({
       type: WATCH_TOKEN_BALANCE,
       payload: {
         tokenAddress,
         balanceOf,
       },
-    };
+    });
   }
-}
+};
 
 export const sync = () => async (dispatch, getState) => {
+  const { getBalance, getTokenBalance } = dispatch(selectors());
   const web3 = await dispatch(initialize());
   const {
     account,
@@ -142,12 +152,17 @@ export const sync = () => async (dispatch, getState) => {
   if (account !== accounts[0]) {
     dispatch({ type: UPDATE_ACCOUNT, payload: accounts[0] });
     dispatch(watchBalance({ balanceOf: accounts[0] }));
-    // dispatch(watchBalance({ balanceOf: accounts[0], tokenAddress: '0xDA5B056Cfb861282B4b59d29c9B395bcC238D29B' }));
   }
 
   // Sync Ethereum Balances
   watched.balances.ethereum.forEach(async address => {
     const balance = await web3.eth.getBalance(address);
+    const { value } = getBalance(address);
+
+
+    if (value.isEqualTo(BN(balance))) {
+      return;
+    }
     dispatch({
       type: UPDATE_ETH_BALANCE,
       payload: {
@@ -178,9 +193,16 @@ export const sync = () => async (dispatch, getState) => {
 
       const watchlist = watched.balances[tokenAddress] || [];
       watchlist.forEach(async address => {
+        const tokenBalance = getTokenBalance(tokenAddress, address);
         const balance = await contract.methods.balanceOf(address).call();
-        const decimals = await contract.methods.decimals().call();
-        const symbol = await contract.methods.symbol().call();
+        const decimals = tokenBalance.decimals || await contract.methods.decimals().call();
+        const symbol = tokenBalance.label || await contract.methods.symbol().call();
+
+        if (tokenBalance.value.isEqualTo(BN(balance))) {
+          console.log('block');
+          return;
+        }
+
         dispatch({
           type: UPDATE_TOKEN_BALANCE,
           payload: {
@@ -200,7 +222,6 @@ export const startWatching = () => async (dispatch, getState) => {
     : 5000;
 
   dispatch(sync());
-
   setTimeout(() => dispatch(startWatching()), timeout);
 };
 
diff --git a/src/index.js b/src/index.js
index 81ef6503d4..bfb6d8bf74 100644
--- a/src/index.js
+++ b/src/index.js
@@ -11,7 +11,7 @@ window.addEventListener('load', function() {
     <DrizzleProvider options={{
       contracts: [],
       events: [],
-      polls: { accounts: 3000, blocks: 3000 },
+      polls: { accounts: 60000, blocks: 60000 },
     }} store={store}>
       <App />
     </DrizzleProvider>
diff --git a/src/pages/Pool/AddLiquidity.js b/src/pages/Pool/AddLiquidity.js
index ddd4d973cd..31c12f966e 100644
--- a/src/pages/Pool/AddLiquidity.js
+++ b/src/pages/Pool/AddLiquidity.js
@@ -8,7 +8,9 @@ import { selectors, sync } from '../../ducks/web3connect';
 import ArrowDown from '../../assets/images/arrow-down-blue.svg';
 import ModeSelector from './ModeSelector';
 import {BigNumber as BN} from 'bignumber.js';
+import EXCHANGE_ABI from '../../abi/exchange';
 import "./pool.scss";
+import promisify from "../../helpers/web3-promisfy";
 
 const INPUT = 0;
 const OUTPUT = 1;
@@ -18,6 +20,7 @@ class AddLiquidity extends Component {
     isConnected: PropTypes.bool.isRequired,
     account: PropTypes.string.isRequired,
     selectors: PropTypes.func.isRequired,
+    balances: PropTypes.object.isRequired,
     exchangeAddresses: PropTypes.shape({
       fromToken: PropTypes.object.isRequired,
     }).isRequired,
@@ -26,11 +29,27 @@ class AddLiquidity extends Component {
   state = {
     inputValue: '',
     outputValue: '',
-    inputCurrency: '',
+    inputCurrency: 'ETH',
     outputCurrency: '',
     lastEditedField: '',
   };
 
+  shouldComponentUpdate(nextProps, nextState) {
+    const { isConnected, account, exchangeAddresses, balances, web3 } = this.props;
+    const { inputValue, outputValue, inputCurrency, outputCurrency, lastEditedField } = this.state;
+
+    return isConnected !== nextProps.isConnected ||
+      account !== nextProps.account ||
+      exchangeAddresses !== nextProps.exchangeAddresses ||
+      web3 !== nextProps.web3 ||
+      balances !== nextProps.balances ||
+      inputValue !== nextState.inputValue ||
+      outputValue !== nextState.outputValue ||
+      inputCurrency !== nextState.inputCurrency ||
+      outputCurrency !== nextState.outputCurrency ||
+      lastEditedField !== nextState.lastEditedField;
+  }
+
   getBalance(currency) {
     const { selectors, account } = this.props;
 
@@ -47,6 +66,34 @@ class AddLiquidity extends Component {
     return `Balance: ${value.dividedBy(10 ** decimals).toFixed(4)}`;
   }
 
+  onAddLiquidity = async () => {
+    const { account, web3, exchangeAddresses: { fromToken }, selectors } = this.props;
+    const { inputValue, outputValue, outputCurrency } = this.state;
+    const exchange = new web3.eth.Contract(EXCHANGE_ABI, fromToken[outputCurrency]);
+
+    const ethAmount = BN(inputValue).multipliedBy(10 ** 18);
+    const { decimals } = selectors().getTokenBalance(outputCurrency, fromToken[outputCurrency]);
+    const tokenAmount = BN(outputValue).multipliedBy(10 ** decimals);
+    const { value: ethReserve } = selectors().getBalance(fromToken[outputCurrency]);
+    const totalLiquidity = await exchange.methods.totalSupply().call();
+    const liquidityMinted = BN(totalLiquidity).multipliedBy(ethAmount.dividedBy(ethReserve));
+    const blockNumber = await promisify(web3, 'getBlockNumber');
+    const block = await promisify(web3, 'getBlock', blockNumber);
+    const deadline = block.timestamp + 300;
+    const MAX_LIQUIDITY_SLIPPAGE = 0.025;
+    const minLiquidity = liquidityMinted.multipliedBy(1 - MAX_LIQUIDITY_SLIPPAGE);
+    const maxTokens = tokenAmount.multipliedBy(1 + MAX_LIQUIDITY_SLIPPAGE);
+
+    try {
+      const tx = await exchange.methods.addLiquidity(minLiquidity.toFixed(0), maxTokens.toFixed(0), deadline).send({
+        from: account,
+        value: ethAmount.toFixed(0)
+      });
+    } catch (err) {
+      console.error(err);
+    }
+  };
+
   onInputChange = value => {
     const { inputCurrency, outputCurrency } = this.state;
     const exchangeRate = this.getExchangeRate();
@@ -103,6 +150,39 @@ class AddLiquidity extends Component {
     return tokenValue.dividedBy(ethValue);
   }
 
+  validate() {
+    const { selectors, account } = this.props;
+    const {
+      inputValue, outputValue,
+      inputCurrency, outputCurrency,
+    } = this.state;
+
+    let inputError;
+    let outputError;
+    let isValid = true;
+
+    if (!inputValue || !outputValue || !inputCurrency || !outputCurrency) {
+      isValid = false;
+    }
+
+    const { value: ethValue } = selectors().getBalance(account);
+    const { value: tokenValue, decimals } = selectors().getTokenBalance(outputCurrency, account);
+
+    if (ethValue.isLessThan(BN(inputValue * 10 ** 18))) {
+      inputError = 'Insufficient Balance';
+    }
+
+    if (tokenValue.isLessThan(BN(outputValue * 10 ** decimals))) {
+      outputError = 'Insufficient Balance';
+    }
+
+    return {
+      inputError,
+      outputError,
+      isValid: isValid && !inputError && !outputError,
+    };
+  }
+
   renderInfo() {
     const { selectors, exchangeAddresses: { fromToken } } = this.props;
     const { inputCurrency, outputCurrency } = this.state;
@@ -136,11 +216,71 @@ class AddLiquidity extends Component {
       <div className="pool__summary-panel">
         <div className="pool__exchange-rate-wrapper">
           <span className="pool__exchange-rate">Exchange Rate</span>
-          <span>{`1 ETH = ${tokenValue.dividedBy(ethValue).toFixed(4)} BAT`}</span>
+          <span>{`1 ETH = ${tokenValue.dividedBy(ethValue).toFixed(4)} ${label}`}</span>
         </div>
         <div className="pool__exchange-rate-wrapper">
           <span className="swap__exchange-rate">Current Pool Size</span>
-          <span>{` ${ethValue.dividedBy(10 ** 18).toFixed(2)} ${eth} / ${tokenValue.dividedBy(10 ** decimals).toFixed(2)} ${label}`}</span>
+          <span>{` ${ethValue.dividedBy(10 ** 18).toFixed(2)} ${eth} + ${tokenValue.dividedBy(10 ** decimals).toFixed(2)} ${label}`}</span>
+        </div>
+      </div>
+    )
+  }
+
+  renderSummary() {
+    const { selectors, exchangeAddresses: { fromToken } } = this.props;
+    const {
+      inputValue,
+      outputValue,
+      inputCurrency,
+      outputCurrency,
+    } = this.state;
+
+    if (!inputCurrency || !outputCurrency) {
+      return (
+        <div className="swap__summary-wrapper">
+          <div>Select a token to continue.</div>
+        </div>
+      )
+    }
+
+    if (inputCurrency === outputCurrency) {
+      return (
+        <div className="swap__summary-wrapper">
+          <div>Must be different token.</div>
+        </div>
+      )
+    }
+
+    if (![inputCurrency, outputCurrency].includes('ETH')) {
+      return (
+        <div className="swap__summary-wrapper">
+          <div>One of the input must be ETH.</div>
+        </div>
+      )
+    }
+
+    const { value, decimals, label } = selectors().getTokenBalance(outputCurrency, fromToken[outputCurrency]);
+
+    if (!inputValue || !outputValue) {
+      return (
+        <div className="swap__summary-wrapper">
+          <div>{`Enter a ${inputCurrency} or ${label} value to continue.`}</div>
+        </div>
+      )
+    }
+
+    const SLIPPAGE = 0.025;
+    const minOutput = BN(outputValue).multipliedBy(1 - SLIPPAGE);
+    const maxOutput = BN(outputValue).multipliedBy(1 + SLIPPAGE);
+    const tokenReserve = value.dividedBy(10 ** decimals);
+    const minPercentage = minOutput.dividedBy(minOutput.plus(tokenReserve)).multipliedBy(100);
+    const maxPercentage = maxOutput.dividedBy(maxOutput.plus(tokenReserve)).multipliedBy(100);
+
+    return (
+      <div className="swap__summary-wrapper">
+        <div>You are adding between {b(`${minOutput.toFixed(2)} - ${maxOutput.toFixed(2)} ${label}`)} + {b(`${BN(inputValue).toFixed(2)} ETH`)} into the liquidity pool.</div>
+        <div className="pool__last-summary-text">
+          You will receive between {b(`${minPercentage.toFixed(2)}%`)} and {b(`${maxPercentage.toFixed(2)}%`)} of the {`${label}/ETH`} pool tokens.
         </div>
       </div>
     )
@@ -159,19 +299,23 @@ class AddLiquidity extends Component {
       lastEditedField,
     } = this.state;
 
+    const { inputError, outputError, isValid } = this.validate();
+
     return (
-      <div className={classnames('swap__content', { 'swap--inactive': !isConnected })}>
+      <div
+        className={classnames('swap__content', {
+          'swap--inactive': !isConnected,
+        })}
+      >
         <ModeSelector />
         <CurrencyInputPanel
           title="Deposit"
-          description={lastEditedField === OUTPUT ? '(estimated)' : ''}
           extraText={this.getBalance(inputCurrency)}
-          onCurrencySelected={currency => {
-            this.setState({ inputCurrency: currency });
-            this.props.sync();
-          }}
           onValueChange={this.onInputChange}
+          selectedTokenAddress="ETH"
           value={inputValue}
+          errorMessage={inputError}
+          disableTokenSelect
         />
         <OversizedPanel>
           <div className="swap__down-arrow-background">
@@ -180,32 +324,32 @@ class AddLiquidity extends Component {
         </OversizedPanel>
         <CurrencyInputPanel
           title="Deposit"
-          description={lastEditedField === INPUT ? '(estimated)' : ''}
+          description="(estimated)"
           extraText={this.getBalance(outputCurrency)}
+          selectedTokenAddress={outputCurrency}
           onCurrencySelected={currency => {
             this.setState({ outputCurrency: currency });
             this.props.sync();
           }}
           onValueChange={this.onOutputChange}
           value={outputValue}
+          errorMessage={outputError}
+          filteredTokens={[ 'ETH' ]}
         />
         <OversizedPanel hideBottom>
-        { this.renderInfo() }
+          { this.renderInfo() }
         </OversizedPanel>
-        <div className="swap__summary-wrapper">
-          <div>You are adding between {b`212000.00 - 216000.00 BAT`} + {b`166.683543 ETH`} into the liquidity pool.</div>
-          <div className="pool__last-summary-text">You will receive between {b`66%`} and {b`67%`} of the BAT/ETH pool tokens.</div>
-        </div>
+        { this.renderSummary() }
         <div className="pool__cta-container">
           <button
             className={classnames('pool__cta-btn', {
               'swap--inactive': !this.props.isConnected,
-              'pool__cta-btn--inactive': !this.props.isValid,
+              'pool__cta-btn--inactive': !isValid,
             })}
-            disabled={!this.props.isValid}
-            onClick={this.onSwap}
+            disabled={!isValid}
+            onClick={this.onAddLiquidity}
           >
-            Swap
+            Add Liquidity
           </button>
         </div>
       </div>
@@ -219,6 +363,7 @@ export default drizzleConnect(
     isConnected: Boolean(state.web3connect.account),
     account: state.web3connect.account,
     balances: state.web3connect.balances,
+    web3: state.web3connect.web3,
     exchangeAddresses: state.addresses.exchangeAddresses,
   }),
   dispatch => ({
diff --git a/src/variables.scss b/src/variables.scss
index 03ae02311a..33b4ee6cae 100644
--- a/src/variables.scss
+++ b/src/variables.scss
@@ -11,6 +11,7 @@ $mine-shaft-gray: #2B2B2B;
 
 // Blue
 $zumthor-blue: #EBF4FF;
+$malibu-blue: #5CA2FF;
 $royal-blue: #2F80ED;
 
 // Purple