const Container = styled.div` .content input{ background: #152528; border-radius: 12px; height: 55px; font-size:20px; color: #7E8A93; padding:0 15px 0 15px; border:none; outline:none; margin-bottom:8px; } .content input:focus{ outline:none; } input::-webkit-outer-spin-button, input::-webkit-inner-spin-button { -webkit-appearance: none; } .content .balance { font-size:12px; color:#4B6778; margin-left:6px; } .template{ display:flex; align-items:center; justify-content:space-between; margin-left:6px; } .template .title{ font-size:14px; color:#7E8A93; } .template .value{ font-size:14px; color:#fff; } .mt_25{ margin-top:25px; } .mt-10{ margin-top:10px; } .greenButton{ display:flex; align-items:center; justify-content:center; background: #00FFD1; border-radius: 12px; height:46px; font-weight: 700; font-size: 18px; color:#000; cursor:pointer; width:100%; } .disabled{ opacity:0.3; cursor: not-allowed; } `; /** base tool start */ let MAX_RATIO = 10_000; let BURROW_CONTRACT = "contract.main.burrow.near"; let accountId = context.accountId; let B = Big(); B.DP = 60; // set precision to 60 decimals const toAPY = (v) => Math.round(v * 100) / 100; const clone = (o) => JSON.parse(JSON.stringify(o)); const shrinkToken = (value, decimals) => { return B(value).div(B(10).pow(decimals)); }; const expandToken = (value, decimals) => { return B(value).mul(B(10).pow(decimals)); }; const formatToken = (v) => Math.floor(v * 10_000) / 10_000; const power = (x, y) => { if (y === 0) { return 1; } else if (y % 2 === 0) { return power(x, parseInt(y / 2)) * power(x, parseInt(y / 2)); } else { return x * power(x, parseInt(y / 2)) * power(x, parseInt(y / 2)); } }; const nFormat = (num, digits) => { const lookup = [ { value: 1, symbol: "" }, { value: 1e3, symbol: "k" }, { value: 1e6, symbol: "M" }, ]; const rx = /\.0+$|(\.[0-9]*[1-9])0+$/; var item = lookup .slice() .reverse() .find((item) => num >= item.value); return item ? (num / item.value).toFixed(digits).replace(rx, "$1") + item.symbol : "0"; }; const selectedTokenId = props.selectedTokenId; const { rewards, account, balances, amount, hasError, assets } = state; const hasData = assets.length > 0 && rewards.length > 0 && account; /** base tool end */ if (!accountId) { return <Widget src="juaner.near/widget/ref_account-signin" />; } const config = Near.view(BURROW_CONTRACT, "get_config"); const onLoad = (data) => { State.update(data); }; const rewardsMap = rewards ? rewards.reduce((acc, cur) => { return { ...acc, [cur.token_id]: cur, }; }, {}) : {}; const assetsMap = assets ? assets.reduce((acc, cur) => { return { ...acc, [cur.token_id]: cur, }; }, {}) : {}; /** logic start */ function getAdjustedSum(type, account) { if (!assets || !account || account[type].length == 0) return B(1); return account[type] .map((assetInAccount) => { const asset = assets.find((a) => a.token_id === assetInAccount.token_id); const price = asset.price ? B(asset.price.multiplier).div(B(10).pow(asset.price.decimals)) : B(0); const pricedBalance = B(assetInAccount.balance) .div(expandToken(1, asset.config.extra_decimals)) .mul(price); return type === "borrowed" ? pricedBalance .div(asset.config.volatility_ratio) .mul(MAX_RATIO) .toFixed() : pricedBalance .mul(asset.config.volatility_ratio) .div(MAX_RATIO) .toFixed(); }) .reduce((sum, cur) => B(sum).plus(B(cur)).toFixed()); } const adjustedCollateralSum = getAdjustedSum("collateral", account); const adjustedBorrowedSum = getAdjustedSum("borrowed", account); function getHealthFactor() { const healthFactor = B(adjustedCollateralSum) .div(B(adjustedBorrowedSum)) .mul(100) .toFixed(0); return Number(healthFactor) < MAX_RATIO ? healthFactor : MAX_RATIO; } const healthFactor = getHealthFactor(); const recomputeHealthFactor = (tokenId, amount) => { if (!tokenId || !amount) return null; const asset = assets.find((a) => a.token_id === tokenId); const decimals = asset.metadata.decimals + asset.config.extra_decimals; const accountBorrowedAsset = account.borrowed.find( (a) => a.token_id === tokenId ); const newBalance = expandToken(amount, decimals) .plus(B(accountBorrowedAsset?.balance || 0)) .toFixed(); const clonedAccount = clone(account); const updatedToken = { token_id: tokenId, balance: newBalance, shares: newBalance, apr: "0", }; if (clonedAccount?.borrowed.length === 0) { clonedAccount.borrowed = updatedToken; } else if (!accountBorrowedAsset) { clonedAccount.borrowed.push(updatedToken); } else { clonedAccount.borrowed = [ ...clonedAccount.borrowed.filter((a) => a.token_id !== tokenId), updatedToken, ]; } const adjustedCollateralSum = getAdjustedSum("collateral", account); const adjustedBorrowedSum = getAdjustedSum( "borrowed", amount === 0 ? account : clonedAccount ); const newHealthFactor = B(adjustedCollateralSum) .div(B(adjustedBorrowedSum)) .mul(100) .toNumber(); return newHealthFactor; }; // get max ammount can be borrowed function getMaxAmount() { if (!selectedTokenId || !assets) return 0; const asset = assets.find((a) => a.token_id === selectedTokenId); const volatiliyRatio = asset.config.volatility_ratio || 0; const price = asset.price?.usd || Infinity; const available = Number( B(adjustedCollateralSum) .sub(B(adjustedBorrowedSum)) .mul(volatiliyRatio) .div(MAX_RATIO) .div(price) .mul(95) .div(100) .toFixed(4) ); return [available, (asset.price.usd * available).toFixed(2)]; } const [available, availableUSD] = getMaxAmount(); const storageBurrow = Near.view(BURROW_CONTRACT, "storage_balance_of", { account_id: accountId, }); // get the storage deposit for a token const storageToken = selectedTokenId ? Near.view(selectedTokenId, "storage_balance_of", { account_id: accountId, }) : null; const handleAmount = (e) => { const amount = Number(e.target.value); State.update({ amount, selectedTokenId, hasError: false, }); handleBlur(amount); }; const handleBlur = (amount) => { State.update({ newHealthFactor: recomputeHealthFactor(selectedTokenId, amount), }); }; const handleBorrow = () => { if (!selectedTokenId || !amount || hasError) return; const asset = assets.find((a) => a.token_id === selectedTokenId); if (amount > available) { State.update({ selectedTokenId, amount, hasError: true }); return; } const transactions = []; const expandedAmount = expandToken( amount, asset.metadata.decimals + asset.config.extra_decimals ); const borrowTemplate = { Execute: { actions: [ { Borrow: { token_id: selectedTokenId, amount: expandedAmount.toFixed(0), }, }, { Withdraw: { token_id: selectedTokenId, max_amount: expandedAmount.toFixed(0), }, }, ], }, }; const borrowTransaction = { contractName: config.oracle_account_id, methodName: "oracle_call", deposit: B("1").toFixed(), gas: expandToken(300, 12), args: { receiver_id: BURROW_CONTRACT, msg: JSON.stringify(borrowTemplate), }, }; if (storageToken?.available === "0" || !storageToken?.available) { transactions.push({ contractName: selectedTokenId, methodName: "storage_deposit", deposit: expandToken(0.25, 24).toFixed(), }); } if (storageBurrow?.available === "0" || !storageBurrow?.available) { transactions.push({ contractName: BURROW_CONTRACT, methodName: "storage_deposit", deposit: expandToken(0.25, 24).toFixed(), gas: expandToken(140, 12), }); } transactions.push(borrowTransaction); if ( ["wrap.near", "wrap.testnet"].includes(selectedTokenId) && expandedAmount.gt(10) ) { transactions.push({ contractName: selectedTokenId, methodName: "near_withdraw", deposit: B("1").toFixed(), args: { amount: expandedAmount.sub(10).toFixed(0), }, }); } Near.call(transactions); }; const reward = rewards && rewards.find((a) => a.token_id === selectedTokenId); const newHealthFactor = state.newHealthFactor ? state.newHealthFactor?.toFixed() : undefined; /** logic end */ return ( <Container> {/* load data */} {!hasData && ( <Widget src="juaner.near/widget/ref_burrow-data" props={{ onLoad }} /> )} <div class="content"> <input type="number" value={amount} onChange={handleAmount} /> {selectedTokenId && ( <span class="balance"> Balance: {available} (${availableUSD}) </span> )} {hasError && ( <p class="alert alert-danger mt-10" role="alert"> Amount greater than available </p> )} <div class="template mt_25"> <span class="title">Borrow APY</span> <span class="value"> {selectedTokenId && <>{toAPY(reward.apyBaseBorrow)}%</>} </span> </div> <div class="template mt_25"> <span class="title">Health Factor</span> <span class="value"> {newHealthFactor ? newHealthFactor : healthFactor}% </span> </div> <div class={`greenButton mt_25 ${Number(amount) ? "" : "disabled"}`} onClick={handleBorrow} > Borrow </div> </div> </Container> );