// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/IERC20.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);

    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);

    /**
     * @dev Moves `amount` tokens from the caller's account to `to`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address to, uint256 amount) external returns (bool);

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);

    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);

    /**
     * @dev Moves `amount` tokens from `from` to `to` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address from, address to, uint256 amount) external returns (bool);
}

// SPDX-License-Identifier: GPL-3.0
pragma solidity 0.8.19;

interface IUSDeSiloDefinitions {
  /// @notice Error emitted when the staking vault is not the caller
  error OnlyStakingVault();
}

// SPDX-License-Identifier: GPL-3.0
pragma solidity ^0.8.0;

/* solhint-disable var-name-mixedcase  */

import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "../contracts/interfaces/IUSDeSiloDefinitions.sol";

/**
 * @title USDeSilo
 * @notice The Silo allows to store USDe during the stake cooldown process.
 */
contract USDeSilo is IUSDeSiloDefinitions {
  address immutable _STAKING_VAULT;
  IERC20 immutable _USDE;

  constructor(address stakingVault, address usde) {
    _STAKING_VAULT = stakingVault;
    _USDE = IERC20(usde);
  }

  modifier onlyStakingVault() {
    if (msg.sender != _STAKING_VAULT) revert OnlyStakingVault();
    _;
  }

  function withdraw(address to, uint256 amount) external onlyStakingVault {
    _USDE.transfer(to, amount);
  }
}

{
  "compilationTarget": {
    "contracts/USDeSilo.sol": "USDeSilo"
  },
  "evmVersion": "paris",
  "libraries": {},
  "metadata": {
    "bytecodeHash": "ipfs"
  },
  "optimizer": {
    "enabled": true,
    "runs": 20000
  },
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    ":@aave/periphery-v3/=lib/aave-helpers/lib/aave-address-book/lib/aave-v3-periphery/",
    ":@bgd-helpers/=lib/aave-helpers/src/",
    ":@openzeppelin/contracts-upgradeable/=lib/openzeppelin-contracts-upgradeable/contracts/",
    ":@openzeppelin/contracts/=lib/openzeppelin-contracts/contracts/",
    ":aave-address-book/=lib/aave-helpers/lib/aave-address-book/src/",
    ":aave-helpers/=lib/aave-helpers/",
    ":aave-v3-core/=lib/aave-v3-core/",
    ":aave-v3-periphery/=lib/aave-helpers/lib/aave-address-book/lib/aave-v3-periphery/",
    ":ds-test/=lib/forge-std/lib/ds-test/src/",
    ":erc4626-tests/=lib/openzeppelin-contracts-upgradeable/lib/erc4626-tests/",
    ":forge-std/=lib/forge-std/src/",
    ":governance-crosschain-bridges/=lib/aave-helpers/lib/governance-crosschain-bridges/",
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    ":openzeppelin-contracts/=lib/openzeppelin-contracts/",
    ":openzeppelin/=lib/openzeppelin-contracts-upgradeable/contracts/",
    ":solidity-utils/=lib/aave-helpers/lib/solidity-utils/src/"
  ]
}