71 lines
2.3 KiB
Solidity
71 lines
2.3 KiB
Solidity
// SPDX-License-Identifier: MIT
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pragma solidity ^0.8.20;
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import "./libraries/FixedPoint.sol";
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import "@openzeppelin-contracts/utils/Address.sol";
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import "@openzeppelin-contracts/token/ERC20/IERC20.sol";
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import "@openzeppelin-contracts/token/ERC20/utils/SafeERC20.sol";
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import "@openzeppelin-contracts/token/ERC20/extensions/IERC20Metadata.sol";
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import "@uniswap-v2-core/interfaces/IUniswapV2ERC20.sol";
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import "@uniswap-v2-core/interfaces/IUniswapV2Pair.sol";
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import "./interfaces/IBondingCalculator.sol";
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contract GhostBondingCalculator is IBondingCalculator {
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using FixedPoint for *;
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address internal immutable ftso;
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constructor(address _ftso) {
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ftso = _ftso;
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}
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function getKValue(address pair) public view returns (uint256 k) {
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uint256 token0 = IERC20Metadata(IUniswapV2Pair(pair).token0()).decimals();
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uint256 token1 = IERC20Metadata(IUniswapV2Pair(pair).token1()).decimals();
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uint256 decimals = token0 + token1 - IERC20Metadata(pair).decimals();
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(uint256 reserve0, uint256 reserve1, ) = IUniswapV2Pair(pair).getReserves();
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k = reserve0 * reserve1 / (10**decimals);
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}
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function getTotalValue(address pair) public view returns (uint256 value) {
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return _sqrt(getKValue(pair)) * 2;
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}
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function valuation(address pair, uint256 amount) external view override returns (uint256 value) {
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uint256 totalValue = getTotalValue(pair);
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uint256 totalSupply = IUniswapV2Pair(pair).totalSupply();
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value = totalValue * FixedPoint.fraction(amount, totalSupply).decode112with18() / 1e18;
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}
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function markdown(address pair) external view override returns (uint256 reserve) {
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(uint256 reserve0, uint256 reserve1, ) = IUniswapV2Pair(pair).getReserves();
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if (IUniswapV2Pair(pair).token0() == ftso) {
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reserve = reserve1;
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} else {
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if (IUniswapV2Pair(pair).token1() != ftso) revert InvalidPair();
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reserve = reserve0;
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}
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reserve = reserve * (2 * 1e9) / getTotalValue(pair);
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}
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function _sqrt(uint256 a) private pure returns (uint256 c) {
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if (a > 3) {
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c = a;
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uint256 b = (a / 2) + 1;
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while (b < c) {
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c = b;
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b = ((a / b) + b) / 2;
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}
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} else if (a != 0) {
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c = 1;
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}
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}
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}
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