// File: @openzeppelin/contracts/access/Ownable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (access/Ownable.sol)

pragma solidity ^0.8.0;

import "../utils/Context.sol";

/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
abstract contract Ownable is Context {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor() {
        _transferOwnership(_msgSender());
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        _checkOwner();
        _;
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if the sender is not the owner.
     */
    function _checkOwner() internal view virtual {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby disabling any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        _transferOwnership(address(0));
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        _transferOwnership(newOwner);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Internal function without access restriction.
     */
    function _transferOwnership(address newOwner) internal virtual {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}

// File: @openzeppelin/contracts/token/ERC20/IERC20.sol



// 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);
}

// File: @openzeppelin/contracts/utils/Context.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)

pragma solidity ^0.8.0;

/**
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}

// File: contracts/interfaces/IMintableBurnableERC20.sol



// SPDX-License-Identifier: GPL-3.0

pragma solidity 0.8.17;

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

interface IMintableBurnableERC20 is IERC20 {
    function mint(address _to, uint256 _amount) external;
    function burn(uint256 _amount) external;
    function transferOwner(address _owner) external;
    function setMinter(address _minter, bool _status) external;
}

// File: contracts/interfaces/IStETH.sol



// SPDX-License-Identifier: GPL-3.0
pragma solidity 0.8.17;

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

interface IStETH is IERC20 {
    function submit(address _referral) external payable returns (uint _recievedShares);
}

// File: contracts/interfaces/IVault.sol



// SPDX-License-Identifier: GPL-3.0

pragma solidity 0.8.17;

import "./IVaultFactory.sol";

interface IVault {
    function initialize(address) external;

    function factory() external view returns (IVaultFactory);
    function owner() external view returns (address);
    function deposited() external view returns (uint);
    function minted() external view returns (uint);
    function availableBalance() external view returns (uint);
    function pendingYield() external view returns (uint);
    function mintRatio() external view returns (uint);
    
    function deposit(uint) external returns (uint);
    function withdraw(uint) external;
    function mint(uint) external;
    function burn(uint) external;
    function redeem(uint) external;
    function claim() external;
}

// File: contracts/interfaces/IVaultFactory.sol



// SPDX-License-Identifier: GPL-3.0

pragma solidity 0.8.17;

import "./IMintableBurnableERC20.sol";

interface IVaultFactory {
    function collateral() external view returns (IERC20);
    function token() external view returns (IMintableBurnableERC20);
    function feeManager() external view returns (address);

    function createVault(address) external returns (address);
    function getVault(address) external view returns (address);
    function allVaults(uint) external view returns (address);
    function isVault(address) external view returns (bool);
    function isVaultManager(address) external view returns (bool);
    function vaultsLength() external view returns (uint);
}

// File: contracts/peripheral/VaultManager.sol



// SPDX-License-Identifier: GPL-3.0

pragma solidity 0.8.17;

import "@openzeppelin/contracts/access/Ownable.sol";
import "../interfaces/IVaultFactory.sol";
import "../interfaces/IVault.sol";
import "../interfaces/IStETH.sol";

// Stateless contracts for executing vault interactions. Used by external contracts, UIs and looper admins.
contract VaultManager is Ownable {

    IVaultFactory public immutable factory;

    constructor(address _factory) {
        factory = IVaultFactory(_factory);
    }

    function depositAndMintWithETH(uint _mintAmount) external payable {
        IStETH stETH = IStETH(address(factory.collateral()));
        uint before = factory.collateral().balanceOf(address(this));
        if (msg.value > 0) {
            stETH.submit{value: msg.value}(address(0));
        }
        uint actualDepositedAmount = factory.collateral().balanceOf(address(this)) - before;
        _depositAndMint(actualDepositedAmount, _mintAmount);
    }

    function depositAndMint(uint _depositAmount, uint _mintAmount) external {
        uint before = factory.collateral().balanceOf(address(this));
        factory.collateral().transferFrom(msg.sender, address(this), _depositAmount);
        uint actualDepositedAmount = factory.collateral().balanceOf(address(this)) - before;
        _depositAndMint(actualDepositedAmount, _mintAmount);
    }

    function _depositAndMint(uint _depositAmount, uint _mintAmount) internal {
        IVault vault = IVault(factory.getVault(msg.sender));
        require(address(vault) != address(0), "vault not exist");
        if (_depositAmount > 0) {
            factory.collateral().approve(address(vault), _depositAmount);
            vault.deposit(_depositAmount);
        }
        uint available = vault.availableBalance();
        // Cap mint at available balance
        _mintAmount = _mintAmount > available ? available : _mintAmount;

        if (_mintAmount > 0) {
            vault.mint(_mintAmount);
        }
    }

    function burnAndWithdraw(uint _burnAmount, uint _withdrawAmount) external {
        IVault vault = IVault(factory.getVault(msg.sender));
        require(address(vault) != address(0), "vault not exist");
        if (_burnAmount > 0) {
            factory.token().transferFrom(msg.sender, address(this), _burnAmount);
            factory.token().approve(address(vault), _burnAmount);
            vault.burn(_burnAmount);
        }
        if (_withdrawAmount > 0) {
            vault.withdraw(_withdrawAmount);
        }
    }

    function redeem(uint _amount, IVault[] calldata vaults) external {
        uint vaultManagerCollateralBefore = factory.collateral().balanceOf(address(this));
        factory.token().transferFrom(msg.sender, address(this), _amount);
        for (uint i=0; i<vaults.length; i++) {
            uint amountToRedeem = _amount > vaults[i].minted() ? vaults[i].minted() : _amount;

            // skip vaults with no minted tokens
            if (amountToRedeem > 0) {
                factory.token().approve(address(vaults[i]), amountToRedeem);
                vaults[i].redeem(amountToRedeem);
                _amount -= amountToRedeem;
            }

            if (_amount == 0) break;
        }
        // caclulate amount of collateral redeemed and transfer to msg.sender
        uint redeemed = factory.collateral().balanceOf(address(this)) - vaultManagerCollateralBefore;
        factory.collateral().transfer(msg.sender, redeemed);

        require(_amount == 0, "VaultManager: insufficient vault balance to redeem");
    }

    // Manager should not have any balances, allow rescuing of accidental transfers
    function rescue(address _token, address _recipient) external onlyOwner {
        uint _balance = IERC20(_token).balanceOf(address(this));
        IERC20(_token).transfer(_recipient, _balance);
    }
}