// 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/earn/FeeDistributor.sol



// SPDX-License-Identifier: GPL-3.0

pragma solidity 0.8.17;

import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "../interfaces/IRewardsDistributionRecipient.sol";
import "../interfaces/IVaultFactory.sol";
import "../interfaces/IVault.sol";
import "../interfaces/IWstETH.sol";
import "../interfaces/IFeeWallet.sol";
import "../interfaces/IFeeManager.sol";

// FeeDistributor is a contract that collects fee (in wstETH) from fee wallets (Protocol Fee Wallet and Redemption Fee Wallet) 
// and distribute to recipients contract (e.g., StakingRewards)
contract FeeDistributor is Ownable {

    /* ========== STATE VARIABLES ========== */

    IRewardsDistributionRecipient[] public recipients;
    uint256[] public protocolFeeShares; // how many shares recipients[i] gets of protocolFee
    uint256[] public redemptionFeeShares; // how many shares recipients[i] gets of redemptionFee
    uint256 public toalProtocolFeeShares;
    uint256 public totalRedemptionFeeShares;

    IVaultFactory public factory;
    
    mapping(address => bool) public keepers;
    bool public allowPublicKeeper;
    uint public keeperFee = 1e17; // flat fee in reward token

    /* ========== CONSTRUCTOR ========== */

    constructor(IVaultFactory _factory) {
        factory = _factory;
    }

    /* ========== ADMIN FUNCTIONS ========== */

    function setKeeper(address _address, bool _status) external onlyOwner {
        keepers[_address] = _status;
    }

    function setAllowPublicKeeper(bool _status) external onlyOwner {
        allowPublicKeeper = _status;
    }

    function setDistribution(
        IRewardsDistributionRecipient[] calldata _recipients,
        uint256[] calldata _protocolFeeShares,
        uint256[] calldata _redemptionFeeShares
    )
        external
        onlyOwner
    {
        require(_recipients.length == _protocolFeeShares.length && _recipients.length == _redemptionFeeShares.length, "!length");

        recipients = _recipients;
        protocolFeeShares = _protocolFeeShares;
        redemptionFeeShares = _redemptionFeeShares;

        // recalculate total shares
        uint256 _totalProtocolFeeShares;
        uint256 _totalRedemptionFeeShares;
        for (uint256 i = 0; i < _recipients.length; i++) {
            _totalProtocolFeeShares += _protocolFeeShares[i];
            _totalRedemptionFeeShares += _redemptionFeeShares[i];
        }
        toalProtocolFeeShares = _totalProtocolFeeShares;
        totalRedemptionFeeShares = _totalRedemptionFeeShares;
    }

    function setKeeperFee(uint _keeperFee) external onlyOwner {
        keeperFee = _keeperFee;
    }

    function rescue(address _token, address _recipient) external onlyOwner {
        uint _balance = IERC20(_token).balanceOf(address(this));
        IERC20(_token).transfer(_recipient, _balance);
    }

    /* ========== MUTATIVE FUNCTIONS ========== */

    // Claim pending rewards from all vaults
    function claimAll() public {
        uint len = factory.vaultsLength();
        for (uint i=0; i<len; i++) {
            IVault(factory.allVaults(i)).claim();
        }
    }

    // Claim from all vaults with pending rewards > _pending
    function claimAllGreaterThan(uint _pending) public {
        uint len = factory.vaultsLength();
        for (uint i=0; i<len; i++) {
            IVault vault = IVault(factory.allVaults(i));
            if (vault.pendingYield() >= _pending) {
                vault.claim();
            }
        }
    }

    // Claim from selected vaults
    function claimSome(IVault[] calldata vaults) public {
        uint len = vaults.length;
        for (uint i=0; i<len; i++) {
            vaults[i].claim();
        }
    }

    function claimAllAndDistribute() external onlyKeeperOrAllowPublicKeeper {
        claimAll();
        _distributeFee();
    }

    function claimAllGreaterThanAndDistribute(uint _pending) external onlyKeeper {
        claimAllGreaterThan(_pending);
        _distributeFee();
    }

    function claimSomeAndDistribute(IVault[] calldata vaults) external onlyKeeper {
        claimSome(vaults);
        _distributeFee();
    }

    /* ========== INTERNAL FUNCTIONS ========== */

    // get fee (wstETH) from fee wallets (ProtocolFeeWallet and RedemptionFeeWallet) and distribute to recipients contract
    function _distributeFee() internal {
        IFeeWallet protocolFeeWallet = IFeeWallet(IFeeManager(factory.feeManager()).protocolFeeTo());
        IFeeWallet redemptionFeeWallet = IFeeWallet(IFeeManager(factory.feeManager()).redemptionFeeTo());

        uint protocolFee = protocolFeeWallet.withdraw();
        uint redemptionFee = redemptionFeeWallet.withdraw();
        // protocolFeeWallet and redemptionFeeWallet use same fee token (wstETH)
        IERC20 feeToken = IERC20(protocolFeeWallet.feeToken());        
        // Pay keeper
        // we make the keeper fee be shared between protocol fee and redemption fee (proportionally), because
        // 1. it's fair
        // 2. even if one of the fee (e.g., protocol fee) is 0, the reward from another fee (redemption fee) can still be distributed
        require(protocolFee + redemptionFee > keeperFee, "not enough fee collected");
        uint keeperFeeFromProtocolFee =  keeperFee * protocolFee / (protocolFee + redemptionFee);
        uint keeperFeeFromRedemptionFee = keeperFee * redemptionFee / (protocolFee + redemptionFee);
        protocolFee -= keeperFeeFromProtocolFee;
        redemptionFee -= keeperFeeFromRedemptionFee;
        feeToken.transfer(msg.sender, keeperFeeFromProtocolFee + keeperFeeFromRedemptionFee);

        // Distribute to recipient
        for (uint i = 0; i < recipients.length; i++) {
            // Revert if recipient reward period not finished
            IRewardsDistributionRecipient recipient = recipients[i];
            require(block.timestamp >= recipient.periodFinish(), "!finished");
            uint256 amount = protocolFee * protocolFeeShares[i] / toalProtocolFeeShares + redemptionFee * redemptionFeeShares[i] / totalRedemptionFeeShares;
            // Send reward and notify
            feeToken.transfer(address(recipient), amount);
            recipient.notifyRewardAmount(amount);
            emit DistributedReward(msg.sender, address(recipient), address(feeToken), amount);
        }
    }

    /* ========== MODIFIERS ========== */
    

    modifier onlyKeeperOrAllowPublicKeeper() {
        require(keepers[msg.sender] == true || allowPublicKeeper, "!allowed");
        _;
    }

    modifier onlyKeeper() {
        require(keepers[msg.sender] == true, "!keeper");
        _;
    }

    /* ========== EVENTS ========== */

    event DistributedReward(address funder, address recipient, address feeToken, uint256 amount);
}

// File: contracts/interfaces/IFeeManager.sol



// SPDX-License-Identifier: GPL-3.0

pragma solidity 0.8.17;

import "./IMintableBurnableERC20.sol";

interface IFeeManager {
    function protocolFee(address, uint) external view returns (uint);
    function redemptionFee(address, uint) external view returns (uint);
    function protocolRedemptionFeeShare() external view returns (uint);
    function protocolFeeTo() external view returns (address);
    function redemptionFeeTo() external view returns (address);

    function beforeRedeem(uint) external;
    function afterRedeem(uint) external;
}

// File: contracts/interfaces/IFeeWallet.sol



// SPDX-License-Identifier: GPL-3.0

pragma solidity 0.8.17;

interface IFeeWallet {
    function withdraw() external returns (uint);
    function withdrawRaw() external returns (uint);
    function feeToken() external view returns (address);
    function feeTokenRaw() external view returns (address);
}

// 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/IRewardsDistributionRecipient.sol



// SPDX-License-Identifier: GPL-3.0

pragma solidity 0.8.17;

interface IRewardsDistributionRecipient {
    function notifyRewardAmount(uint256 reward) external;
    function periodFinish() external view returns (uint);
}

// 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/interfaces/IWstETH.sol



// SPDX-License-Identifier: GPL-3.0

pragma solidity 0.8.17;

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

interface IWstETH is IERC20 {
    function getWstETHByStETH(uint _stETHAmount) external view returns (uint _wstETHAmount);
    function getStETHByWstETH(uint _wstETHAmount) external view returns (uint _stETHAmount);
    function stETH() external view returns (address);
    
    function wrap(uint256 _stETHAmount) external returns (uint _receivedWstETHAmount);
    function unwrap(uint256 _wstETHAmount) external returns (uint _receivedStETHAmount);
}