idle_moloch/lib/swap-router-contracts/contracts/lens/MixedRouteQuoterV1.sol

238 lines
9.1 KiB
Solidity

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity =0.7.6;
pragma abicoder v2;
import '@uniswap/v3-periphery/contracts/base/PeripheryImmutableState.sol';
import '@uniswap/v3-core/contracts/libraries/SafeCast.sol';
import '@uniswap/v3-core/contracts/libraries/TickMath.sol';
import '@uniswap/v3-core/contracts/libraries/TickBitmap.sol';
import '@uniswap/v3-core/contracts/interfaces/IUniswapV3Pool.sol';
import '@uniswap/v3-core/contracts/interfaces/callback/IUniswapV3SwapCallback.sol';
import '@uniswap/v3-periphery/contracts/libraries/Path.sol';
import '@uniswap/v3-periphery/contracts/libraries/PoolAddress.sol';
import '@uniswap/v3-periphery/contracts/libraries/CallbackValidation.sol';
import '@uniswap/v2-core/contracts/interfaces/IUniswapV2Pair.sol';
import '../base/ImmutableState.sol';
import '../interfaces/IMixedRouteQuoterV1.sol';
import '../libraries/PoolTicksCounter.sol';
import '../libraries/UniswapV2Library.sol';
/// @title Provides on chain quotes for V3, V2, and MixedRoute exact input swaps
/// @notice Allows getting the expected amount out for a given swap without executing the swap
/// @notice Does not support exact output swaps since using the contract balance between exactOut swaps is not supported
/// @dev These functions are not gas efficient and should _not_ be called on chain. Instead, optimistically execute
/// the swap and check the amounts in the callback.
contract MixedRouteQuoterV1 is IMixedRouteQuoterV1, IUniswapV3SwapCallback, PeripheryImmutableState {
using Path for bytes;
using SafeCast for uint256;
using PoolTicksCounter for IUniswapV3Pool;
address public immutable factoryV2;
/// @dev Value to bit mask with path fee to determine if V2 or V3 route
// max V3 fee: 000011110100001001000000 (24 bits)
// mask: 1 << 23 = 100000000000000000000000 = decimal value 8388608
uint24 private constant flagBitmask = 8388608;
/// @dev Transient storage variable used to check a safety condition in exact output swaps.
uint256 private amountOutCached;
constructor(
address _factory,
address _factoryV2,
address _WETH9
) PeripheryImmutableState(_factory, _WETH9) {
factoryV2 = _factoryV2;
}
function getPool(
address tokenA,
address tokenB,
uint24 fee
) private view returns (IUniswapV3Pool) {
return IUniswapV3Pool(PoolAddress.computeAddress(factory, PoolAddress.getPoolKey(tokenA, tokenB, fee)));
}
/// @dev Given an amountIn, fetch the reserves of the V2 pair and get the amountOut
function getPairAmountOut(
uint256 amountIn,
address tokenIn,
address tokenOut
) private view returns (uint256) {
(uint256 reserveIn, uint256 reserveOut) = UniswapV2Library.getReserves(factoryV2, tokenIn, tokenOut);
return UniswapV2Library.getAmountOut(amountIn, reserveIn, reserveOut);
}
/// @inheritdoc IUniswapV3SwapCallback
function uniswapV3SwapCallback(
int256 amount0Delta,
int256 amount1Delta,
bytes memory path
) external view override {
require(amount0Delta > 0 || amount1Delta > 0); // swaps entirely within 0-liquidity regions are not supported
(address tokenIn, address tokenOut, uint24 fee) = path.decodeFirstPool();
CallbackValidation.verifyCallback(factory, tokenIn, tokenOut, fee);
(bool isExactInput, uint256 amountReceived) =
amount0Delta > 0
? (tokenIn < tokenOut, uint256(-amount1Delta))
: (tokenOut < tokenIn, uint256(-amount0Delta));
IUniswapV3Pool pool = getPool(tokenIn, tokenOut, fee);
(uint160 v3SqrtPriceX96After, int24 tickAfter, , , , , ) = pool.slot0();
if (isExactInput) {
assembly {
let ptr := mload(0x40)
mstore(ptr, amountReceived)
mstore(add(ptr, 0x20), v3SqrtPriceX96After)
mstore(add(ptr, 0x40), tickAfter)
revert(ptr, 0x60)
}
} else {
/// since we don't support exactOutput, revert here
revert('Exact output quote not supported');
}
}
/// @dev Parses a revert reason that should contain the numeric quote
function parseRevertReason(bytes memory reason)
private
pure
returns (
uint256 amount,
uint160 sqrtPriceX96After,
int24 tickAfter
)
{
if (reason.length != 0x60) {
if (reason.length < 0x44) revert('Unexpected error');
assembly {
reason := add(reason, 0x04)
}
revert(abi.decode(reason, (string)));
}
return abi.decode(reason, (uint256, uint160, int24));
}
function handleV3Revert(
bytes memory reason,
IUniswapV3Pool pool,
uint256 gasEstimate
)
private
view
returns (
uint256 amount,
uint160 sqrtPriceX96After,
uint32 initializedTicksCrossed,
uint256
)
{
int24 tickBefore;
int24 tickAfter;
(, tickBefore, , , , , ) = pool.slot0();
(amount, sqrtPriceX96After, tickAfter) = parseRevertReason(reason);
initializedTicksCrossed = pool.countInitializedTicksCrossed(tickBefore, tickAfter);
return (amount, sqrtPriceX96After, initializedTicksCrossed, gasEstimate);
}
/// @dev Fetch an exactIn quote for a V3 Pool on chain
function quoteExactInputSingleV3(QuoteExactInputSingleV3Params memory params)
public
override
returns (
uint256 amountOut,
uint160 sqrtPriceX96After,
uint32 initializedTicksCrossed,
uint256 gasEstimate
)
{
bool zeroForOne = params.tokenIn < params.tokenOut;
IUniswapV3Pool pool = getPool(params.tokenIn, params.tokenOut, params.fee);
uint256 gasBefore = gasleft();
try
pool.swap(
address(this), // address(0) might cause issues with some tokens
zeroForOne,
params.amountIn.toInt256(),
params.sqrtPriceLimitX96 == 0
? (zeroForOne ? TickMath.MIN_SQRT_RATIO + 1 : TickMath.MAX_SQRT_RATIO - 1)
: params.sqrtPriceLimitX96,
abi.encodePacked(params.tokenIn, params.fee, params.tokenOut)
)
{} catch (bytes memory reason) {
gasEstimate = gasBefore - gasleft();
return handleV3Revert(reason, pool, gasEstimate);
}
}
/// @dev Fetch an exactIn quote for a V2 pair on chain
function quoteExactInputSingleV2(QuoteExactInputSingleV2Params memory params)
public
view
override
returns (uint256 amountOut)
{
amountOut = getPairAmountOut(params.amountIn, params.tokenIn, params.tokenOut);
}
/// @dev Get the quote for an exactIn swap between an array of V2 and/or V3 pools
/// @notice To encode a V2 pair within the path, use 0x800000 (hex value of 8388608) for the fee between the two token addresses
function quoteExactInput(bytes memory path, uint256 amountIn)
public
override
returns (
uint256 amountOut,
uint160[] memory v3SqrtPriceX96AfterList,
uint32[] memory v3InitializedTicksCrossedList,
uint256 v3SwapGasEstimate
)
{
v3SqrtPriceX96AfterList = new uint160[](path.numPools());
v3InitializedTicksCrossedList = new uint32[](path.numPools());
uint256 i = 0;
while (true) {
(address tokenIn, address tokenOut, uint24 fee) = path.decodeFirstPool();
if (fee & flagBitmask != 0) {
amountIn = quoteExactInputSingleV2(
QuoteExactInputSingleV2Params({tokenIn: tokenIn, tokenOut: tokenOut, amountIn: amountIn})
);
} else {
/// the outputs of prior swaps become the inputs to subsequent ones
(
uint256 _amountOut,
uint160 _sqrtPriceX96After,
uint32 _initializedTicksCrossed,
uint256 _gasEstimate
) =
quoteExactInputSingleV3(
QuoteExactInputSingleV3Params({
tokenIn: tokenIn,
tokenOut: tokenOut,
fee: fee,
amountIn: amountIn,
sqrtPriceLimitX96: 0
})
);
v3SqrtPriceX96AfterList[i] = _sqrtPriceX96After;
v3InitializedTicksCrossedList[i] = _initializedTicksCrossed;
v3SwapGasEstimate += _gasEstimate;
amountIn = _amountOut;
}
i++;
/// decide whether to continue or terminate
if (path.hasMultiplePools()) {
path = path.skipToken();
} else {
return (amountIn, v3SqrtPriceX96AfterList, v3InitializedTicksCrossedList, v3SwapGasEstimate);
}
}
}
}