Integrate WOOFi as liquidity source

Contracts

Two main contracts of WOOFi's swap function are as follows:
  • WooPP.sol: the main swap contract that handles the logic operation, including setting the token info, calculating slippage, calculating the exchange amount and executing trades. it stores all tokens that are supported for trading. In this contract, it defines quote token and base token. Quote token is the reference token (i.e. stablecoins) in the contract and there is only one quote token. The contract can have multiple base tokens and they can be added by the strategist.
  • WooRouter.sol: the router contract that frontend users interact with. It interacts with the lower layer WooPP.sol to execute the sell logic and send back users the desired amount of tokens. This contract also implements the logic to route user orders to 3rd party aggregator (e.g. 1inch) when WooPP.sol does not have sufficient liquidity.
More details about WOOFi smart contract architecture, implementation info, and addresses can be found in Smart Contract Addresses.

Supported assets

WooPP.sol currently supports the following tokens. Quote token is the stablecoin and the rest are base tokens.
BNB Chain
Avalanche
Fantom
Polygon
Token
Address
BNB
0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE
WBNB
0xbb4CdB9CBd36B01bD1cBaEBF2De08d9173bc095c
BTCB
0x7130d2A12B9BCbFAe4f2634d864A1Ee1Ce3Ead9c
ETH
0x2170ed0880ac9a755fd29b2688956bd959f933f8
WOO
0x4691937a7508860f876c9c0a2a617e7d9e945d4b
USDT
0x55d398326f99059fF775485246999027B3197955
Token
Address
AVAX
0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE
WAVAX
0xB31f66AA3C1e785363F0875A1B74E27b85FD66c7
WBTC.e
0x50b7545627a5162F82A992c33b87aDc75187B218
WETH.e
0x49D5c2BdFfac6CE2BFdB6640F4F80f226bc10bAB
WOO.e
0xaBC9547B534519fF73921b1FBA6E672b5f58D083
USDC
0xB97EF9Ef8734C71904D8002F8b6Bc66Dd9c48a6E
Token
Address
FTM
0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE
WFTM
0x21be370D5312f44cB42ce377BC9b8a0cEF1A4C83
BTC
0x321162Cd933E2Be498Cd2267a90534A804051b11
ETH
0x74b23882a30290451A17c44f4F05243b6b58C76d
WOO
0x6626c47c00F1D87902fc13EECfaC3ed06D5E8D8a
USDC
0x04068DA6C83AFCFA0e13ba15A6696662335D5B75
Token
Address
MATIC
0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE
WMATIC
0x0d500B1d8E8eF31E21C99d1Db9A6444d3ADf1270
BTC
0x1BFD67037B42Cf73acF2047067bd4F2C47D9BfD6
ETH
0x7ceB23fD6bC0adD59E62ac25578270cFf1b9f619
WOO
0x1B815d120B3eF02039Ee11dC2d33DE7aA4a8C603
USDC
0x2791Bca1f2de4661ED88A30C99A7a9449Aa84174

Integrating WOOFi's liquidity

When integrating WOOFi as a liquidity source, you can either interact directly with WooPP.sol or throughWooRouter.sol.
For aggregators or trading bots, we recommend integrate directly with WooPP.sol to be more gas efficient.

Contract addresses:

Interface:

/// @dev get the quote token address (immutable)
/// @return address of quote token
function quoteToken() external view returns (address);
​
/// @dev Query the amount for selling the base token amount.
/// @param baseToken the base token to sell
/// @param baseAmount the amount to sell
/// @return quoteAmount the swapped quote amount
function querySellBase(address baseToken, uint256 baseAmount) external view returns (uint256 quoteAmount);
​
/// @dev Query the amount for selling the quote token.
/// @param baseToken the base token to receive (buy)
/// @param quoteAmount the amount to sell
/// @return baseAmount the swapped base token amount
function querySellQuote(address baseToken, uint256 quoteAmount) external view returns (uint256 baseAmount);
​
/// @dev Swap baseToken into quoteToken
/// @param baseToken the base token
/// @param baseAmount amount of baseToken that user want to swap
/// @param minQuoteAmount minimum amount of quoteToken that user accept to receive
/// @param to quoteToken receiver address
/// @param rebateTo the wallet address for rebate
/// @return quoteAmount the swapped amount of quote token
function sellBase(
address baseToken,
uint256 baseAmount,
uint256 minQuoteAmount,
address to,
address rebateTo
) external returns (uint256 quoteAmount);
​
/// @dev Swap quoteToken into baseToken
/// @param baseToken the base token
/// @param quoteAmount amount of quoteToken that user want to swap
/// @param minBaseAmount minimum amount of baseToken that user accept to receive
/// @param to baseToken receiver address
/// @param rebateTo the wallet address for rebate
/// @return baseAmount the swapped amount of base token
function sellQuote(
address baseToken,
uint256 quoteAmount,
uint256 minBaseAmount,
address to,
address rebateTo
) external returns (uint256 baseAmount);

Query & swap functions

address public immutable pool; // IWooPP smart contract
function query(
uint _amountIn,
address _tokenIn,
address _tokenOut
) internal override view returns (uint256 amountOut) {
if (_amountIn == 0) {
return 0;
}
if (_tokenIn == quoteToken) {
amountOut = IWooPP(pool).querySellQuote(_tokenOut, _amountIn);
} else if (_tokenOut == quoteToken) {
amountOut = IWooPP(pool).querySellBase(_tokenIn, _amountIn);
} else {
uint quoteAmount = IWooPP(pool).querySellBase(_tokenIn, _amountIn);
amountOut = IWooPP(pool).querySellQuote(_tokenOut, quoteAmount);
}
}
​
function swap(
uint _amountIn,
uint _amountOut,
address _tokenIn,
address _tokenOut,
address _to
) external returns (uint256 realToAmount) {
// check parameters and approve the allowrance if needed
if (_tokenIn == quoteToken) {
// case 1: quoteToken --> baseToken
realToAmount = IWooPP(pool).sellQuote(
_tokenOut,
_amountIn,
_amountOut,
_to,
address(0)
);
} else if (_tokenOut == quoteToken) {
// case 2: fromToken --> quoteToken
realToAmount = IWooPP(pool).sellBase(
_tokenIn,
_amountIn,
_amountOut,
_to,
address(0)
);
} else {
// case 3: fromToken --> quoteToken --> toToken
uint256 quoteAmount = IWooPP(pool).sellBase(
_tokenIn,
_amountIn,
0,
address(this),
address(0)
);
_approveIfNeeded(quoteToken, quoteAmount);
realToAmount = IWooPP(pool).sellQuote(
_tokenOut,
quoteAmount,
_amountOut,
_to,
address(0)
);
}
​
// emit events if needed
}

Sample intergation code (Yield Yak)

Integrating WooRouter.sol

A simpler way is calling WooRouter.sol contract which provides the similar query and swap as above. This way costs slightly more gas than directly integrating with WooPP.sol.

Contract addresses

Query function
/// @dev query the amount to swap fromToken -> toToken
/// @param fromToken the from token
/// @param toToken the to token
/// @param fromAmount the amount of fromToken to swap
/// @return toAmount the swapped amount to receive
function querySwap(
address fromToken,
address toToken,
uint256 fromAmount
) external view returns (uint256 toAmount);
Sample code to retrieve quote on selling 1 BTC:
wooRouter.querySwap(
0x7130d2A12B9BCbFAe4f2634d864A1Ee1Ce3Ead9c, // btcb token address
0x55d398326f99059fF775485246999027B3197955, // usdt token address
1000000000000000000); // btcb amount to swap in decimal 18
Swap function
/// @dev swap fromToken -> toToken
/// @param fromToken the from token
/// @param toToken the to token
/// @param fromAmount the amount of fromToken to swap
/// @param minToAmount the minimum amount of toToken required or the tx reverts
/// @param to the destination address
/// @param rebateTo the address to receive rebate (rebate rate is set to 0 now)
/// @return realToAmount the amount of toToken to receive
function swap(
address fromToken,
address toToken,
uint256 fromAmount,
uint256 minToAmount,
address payable to,
address rebateTo
) external payable returns (uint256 realToAmount);
Sample code to swap 1 BTC to USDT:
wooRouter.swap(
0x7130d2A12B9BCbFAe4f2634d864A1Ee1Ce3Ead9c, // btcb token address
0x55d398326f99059fF775485246999027B3197955, // usdt token address
1000000000000000000, // btcb amount to swap in decimal 18
990000000000000000, // min amount for 1% slippage
0xd51062A4aF7B76ee0b2893Ef8b52aCC155393E3D, // the address to receive the swap fund
0); // the rebate address

sPMM offchain simulation

For aggregators running offchain routing simulation, you can find the typescript implementation of WOOFi's sPMM algorithm in the github.