// SPDX-License-Identifier: Apache-2.0 pragma solidity >=0.8.0; import "@openzeppelin/contracts/token/ERC20/extensions/ERC4626.sol"; import {HypERC20Collateral} from "./HypERC20Collateral.sol"; /** * @title Hyperlane ERC20 Token Collateral with deposits collateral to a vault * @author ltyu */ contract HypERC20CollateralVaultDeposit is HypERC20Collateral { // Address of the ERC4626 compatible vault ERC4626 public immutable vault; // Internal balance of total asset deposited uint256 public assetDeposited; event ExcessSharesSwept(uint256 amount, uint256 assetsRedeemed); constructor( ERC4626 _vault, address _mailbox ) HypERC20Collateral(_vault.asset(), _mailbox) { vault = _vault; } function initialize( address _hook, address _interchainSecurityModule, address _owner ) public override initializer { wrappedToken.approve(address(vault), type(uint256).max); _MailboxClient_initialize(_hook, _interchainSecurityModule, _owner); } /** * @dev Transfers `_amount` of `wrappedToken` from `msg.sender` to this contract, and deposit into vault * @inheritdoc HypERC20Collateral */ function _transferFromSender( uint256 _amount ) internal override returns (bytes memory metadata) { metadata = super._transferFromSender(_amount); _depositIntoVault(_amount); } /** * @dev Deposits into the vault and increment assetDeposited * @param _amount amount to deposit into vault */ function _depositIntoVault(uint256 _amount) internal { assetDeposited += _amount; vault.deposit(_amount, address(this)); } /** * @dev Transfers `_amount` of `wrappedToken` from this contract to `_recipient`, and withdraws from vault * @inheritdoc HypERC20Collateral */ function _transferTo( address _recipient, uint256 _amount, bytes calldata ) internal virtual override { _withdrawFromVault(_amount, _recipient); } /** * @dev Withdraws from the vault and decrement assetDeposited * @param _amount amount to withdraw from vault * @param _recipient address to deposit withdrawn underlying to */ function _withdrawFromVault(uint256 _amount, address _recipient) internal { assetDeposited -= _amount; vault.withdraw(_amount, _recipient, address(this)); } /** * @notice Allows the owner to redeem excess shares */ function sweep() external onlyOwner { uint256 excessShares = vault.maxRedeem(address(this)) - vault.convertToShares(assetDeposited); uint256 assetsRedeemed = vault.redeem( excessShares, owner(), address(this) ); emit ExcessSharesSwept(excessShares, assetsRedeemed); } }