// File: contracts/peripheral/YieldDirector.sol



// SPDX-License-Identifier: AGPL-3.0-or-later
pragma solidity ^0.8.10;

import {IERC20} from "../interfaces/IERC20.sol";
import {IsOHM} from "../interfaces/IsOHM.sol";
import {SafeERC20} from "../libraries/SafeERC20.sol";
import {IYieldDirector} from "../interfaces/IYieldDirector.sol";
import {OlympusAccessControlled, IOlympusAuthority} from "../types/OlympusAccessControlled.sol";

/**
    @title YieldDirector (codename Tyche) 
    @notice This contract allows donors to deposit their sOHM and donate their rebases
            to any address. Donors will be able to withdraw their principal
            sOHM at any time. Donation recipients can also redeem accrued rebases at any time.
 */
contract YieldDirector is IYieldDirector, OlympusAccessControlled {
    using SafeERC20 for IERC20;

    uint256 private constant MAX_UINT256 = type(uint256).max;

    address public immutable sOHM;

    bool public depositDisabled;
    bool public withdrawDisabled;
    bool public redeemDisabled;

    struct DonationInfo {
        address recipient;
        uint256 deposit; // Total non-agnostic amount deposited
        uint256 agnosticDeposit; // Total agnostic amount deposited
        uint256 carry; // Amount of sOHM accumulated over on deposit/withdraw
        uint256 indexAtLastChange; // Index of last deposit/withdraw
    }

    struct RecipientInfo {
        uint256 totalDebt; // Non-agnostic debt
        uint256 carry; // Total non-agnostic value donating to recipient
        uint256 agnosticDebt; // Total agnostic value of carry + debt
        uint256 indexAtLastChange; // Index when agnostic value changed
    }

    mapping(address => DonationInfo[]) public donationInfo;
    mapping(address => RecipientInfo) public recipientInfo;

    event Deposited(address indexed donor_, address indexed recipient_, uint256 amount_);
    event Withdrawn(address indexed donor_, address indexed recipient_, uint256 amount_);
    event AllWithdrawn(address indexed donor_, uint256 indexed amount_);
    event Donated(address indexed donor_, address indexed recipient_, uint256 amount_);
    event Redeemed(address indexed recipient_, uint256 amount_);
    event EmergencyShutdown(bool active_);

    constructor (address sOhm_, address authority_)
        OlympusAccessControlled(IOlympusAuthority(authority_))
    {
        require(sOhm_ != address(0), "Invalid address for sOHM");

        sOHM = sOhm_;
    }

    /************************
    * Donor Functions
    ************************/

    /**
        @notice Deposit sOHM, records sender address and assign rebases to recipient
        @param amount_ Amount of sOHM debt issued from donor to recipient
        @param recipient_ Address to direct staking yield and vault shares to
    */
    function deposit(uint256 amount_, address recipient_) external override {
        require(!depositDisabled, "Deposits currently disabled");
        require(amount_ > 0, "Invalid deposit amount");
        require(recipient_ != address(0), "Invalid recipient address");

        IERC20(sOHM).safeTransferFrom(msg.sender, address(this), amount_);

        uint256 index = IsOHM(sOHM).index();

        // Record donors's issued debt to recipient address
        DonationInfo[] storage donations = donationInfo[msg.sender];
        uint256 recipientIndex = _getRecipientIndex(msg.sender, recipient_);

        if(recipientIndex == MAX_UINT256) {
            donations.push(
                DonationInfo({
                    recipient: recipient_,
                    deposit: amount_,
                    agnosticDeposit: _toAgnostic(amount_),
                    carry: 0,
                    indexAtLastChange: index
                })
            );
        } else {
            DonationInfo storage donation = donations[recipientIndex];

            donation.carry += _getAccumulatedValue(donation.agnosticDeposit, donation.indexAtLastChange);
            donation.deposit += amount_;
            donation.agnosticDeposit = _toAgnostic(donation.deposit);
            donation.indexAtLastChange = index;
        }

        RecipientInfo storage recipient = recipientInfo[recipient_];

        // Calculate value carried over since last change
        recipient.carry += _getAccumulatedValue(recipient.agnosticDebt, recipient.indexAtLastChange);
        recipient.totalDebt += amount_;
        recipient.agnosticDebt = _toAgnostic(recipient.totalDebt + recipient.carry);
        recipient.indexAtLastChange = index;

        emit Deposited(msg.sender, recipient_, amount_);
    }


    /**
        @notice Withdraw donor's sOHM from vault and subtracts debt from recipient
     */
    function withdraw(uint256 amount_, address recipient_) external override {
        require(!withdrawDisabled, "Withdraws currently disabled");
        require(amount_ > 0, "Invalid withdraw amount");

        uint256 index = IsOHM(sOHM).index();

        // Donor accounting
        uint256 recipientIndex = _getRecipientIndex(msg.sender, recipient_);
        require(recipientIndex != MAX_UINT256, "No donations to recipient");

        DonationInfo storage donation = donationInfo[msg.sender][recipientIndex];

        if(amount_ >= donation.deposit) {
            // Report how much was donated then clear donation information
            uint256 accumulated = donation.carry
                + _getAccumulatedValue(donation.agnosticDeposit, donation.indexAtLastChange);
            emit Donated(msg.sender, recipient_, accumulated);

            delete donationInfo[msg.sender][recipientIndex];

            // If element was in middle of array, bring last element to deleted index
            uint256 lastIndex = donationInfo[msg.sender].length - 1;
            if(recipientIndex != lastIndex) {
                donationInfo[msg.sender][recipientIndex] = donationInfo[msg.sender][lastIndex];
                donationInfo[msg.sender].pop();
            }
        } else {
            donation.carry += _getAccumulatedValue(donation.agnosticDeposit, donation.indexAtLastChange);
            donation.deposit -= amount_;
            donation.agnosticDeposit = _toAgnostic(donation.deposit);
            donation.indexAtLastChange = index;
        }

        // Recipient accounting
        RecipientInfo storage recipient = recipientInfo[recipient_];
        recipient.carry += _getAccumulatedValue(recipient.agnosticDebt, recipient.indexAtLastChange);
        recipient.totalDebt -= amount_;
        recipient.agnosticDebt = _toAgnostic(recipient.totalDebt + recipient.carry);
        recipient.indexAtLastChange = index;

        IERC20(sOHM).safeTransfer(msg.sender, amount_);

        emit Withdrawn(msg.sender, recipient_, amount_);
    }

    /**
        @notice Withdraw from all donor positions
     */
    function withdrawAll() external override {
        require(!withdrawDisabled, "Withdraws currently disabled");

        DonationInfo[] storage donations = donationInfo[msg.sender];

        uint256 donationsLength = donations.length;
        require(donationsLength != 0, "User not donating to anything");

        uint256 sOhmIndex = IsOHM(sOHM).index();
        uint256 total = 0;

        for (uint256 index = 0; index < donationsLength; index++) {
            DonationInfo storage donation = donations[index];

            total += donation.deposit;

            RecipientInfo storage recipient = recipientInfo[donation.recipient];
            recipient.carry += _getAccumulatedValue(recipient.agnosticDebt, recipient.indexAtLastChange);
            recipient.totalDebt -= donation.deposit;
            recipient.agnosticDebt = _toAgnostic(recipient.totalDebt + recipient.carry);
            recipient.indexAtLastChange = sOhmIndex;

            // Report amount donated
            uint256 accumulated = donation.carry
                + _getAccumulatedValue(donation.agnosticDeposit, donation.indexAtLastChange);
            emit Donated(msg.sender, donation.recipient, accumulated);
        }

        // Delete donor's entire donations array
        delete donationInfo[msg.sender];

        IERC20(sOHM).safeTransfer(msg.sender, total);

        emit AllWithdrawn(msg.sender, total);
    }

    /**
        @notice Get deposited sOHM amount for specific recipient
     */
    function depositsTo(address donor_, address recipient_) external override view returns ( uint256 ) {
        uint256 recipientIndex = _getRecipientIndex(donor_, recipient_);
        require(recipientIndex != MAX_UINT256, "No deposits");

        return donationInfo[donor_][recipientIndex].deposit;
    }

    /**
        @notice Return total amount of donor's sOHM deposited
     */
    function totalDeposits(address donor_) external override view returns ( uint256 ) {
        DonationInfo[] storage donations = donationInfo[donor_];
        require(donations.length != 0, "User is not donating");

        uint256 total = 0;
        for (uint256 index = 0; index < donations.length; index++) {
            total += donations[index].deposit;
        }

        return total;
    }
    
    /**
        @notice Return arrays of donor's recipients and deposit amounts, matched by index
     */
    function getAllDeposits(address donor_) external override view returns ( address[] memory, uint256[] memory ) {
        DonationInfo[] storage donations = donationInfo[donor_];
        require(donations.length != 0, "User is not donating");

        uint256 len = donations.length;

        address[] memory addresses = new address[](len);
        uint256[] memory deposits = new uint256[](len);

        for (uint256 index = 0; index < len; index++) {
            addresses[index] = donations[index].recipient;
            deposits[index] = donations[index].deposit;
        }

        return (addresses, deposits);
    }

    /**
        @notice Return total amount of sOHM donated to recipient since last full withdrawal
     */
    function donatedTo(address donor_, address recipient_) external override view returns (uint256) {
        uint256 recipientIndex = _getRecipientIndex(donor_, recipient_);
        require(recipientIndex != MAX_UINT256, "No donations to recipient");

        DonationInfo storage donation = donationInfo[donor_][recipientIndex];
        return donation.carry
            + _getAccumulatedValue(donation.agnosticDeposit, donation.indexAtLastChange);
    }

    /**
        @notice Return total amount of sOHM donated from donor since last full withdrawal
     */
    function totalDonated(address donor_) external override view returns (uint256) {
        DonationInfo[] storage donations = donationInfo[donor_];
        uint256 total = 0;

        for (uint256 index = 0; index < donations.length; index++) {
            DonationInfo storage donation = donations[index];
            total += donation.carry + _getAccumulatedValue(donation.agnosticDeposit, donation.indexAtLastChange);
        }

        return total;
    }

    /************************
    * Recipient Functions
    ************************/

    /**
        @notice Get redeemable sOHM balance of a recipient address
     */
    function redeemableBalance(address recipient_) public override view returns (uint256) {
        RecipientInfo storage recipient = recipientInfo[recipient_];
        return recipient.carry
            + _getAccumulatedValue(recipient.agnosticDebt, recipient.indexAtLastChange);
    }

    /**
        @notice Redeem recipient's full donated amount of sOHM at current index
        @dev Note that a recipient redeeming their vault shares effectively pays back all
             sOHM debt to donors at the time of redeem. Any future incurred debt will
             be accounted for with a subsequent redeem or a withdrawal by the specific donor.
     */
    function redeem() external override {
        require(!redeemDisabled, "Redeems currently disabled");

        uint256 redeemable = redeemableBalance(msg.sender);
        require(redeemable > 0, "No redeemable balance");

        RecipientInfo storage recipient = recipientInfo[msg.sender];
        recipient.agnosticDebt = _toAgnostic(recipient.totalDebt);
        recipient.carry = 0;
        recipient.indexAtLastChange = IsOHM(sOHM).index();

        IERC20(sOHM).safeTransfer(msg.sender, redeemable);

        emit Redeemed(msg.sender, redeemable);
    }

    /************************
    * Utility Functions
    ************************/

    /**
        @notice Get accumulated sOHM since last time agnostic value changed.
     */
    function _getAccumulatedValue(uint256 gAmount_, uint256 indexAtLastChange_) internal view returns (uint256) {
        return _fromAgnostic(gAmount_) - _fromAgnosticAtIndex(gAmount_, indexAtLastChange_);
    }

    /**
        @notice Get array index of a particular recipient in a donor's donationInfo array.
        @return Array index of recipient address. If recipient not present, returns max uint256 value.
     */
    function _getRecipientIndex(address donor_, address recipient_) internal view returns (uint256) {
        DonationInfo[] storage info = donationInfo[donor_];

        uint256 existingIndex = MAX_UINT256;
        for (uint256 i = 0; i < info.length; i++) {
            if(info[i].recipient == recipient_) {
                existingIndex = i;
                break;
            }
        }
        return existingIndex;
    }

    /**
        @notice Convert flat sOHM value to agnostic value at current index
        @dev Agnostic value earns rebases. Agnostic value is amount / rebase_index.
             1e9 is because sOHM has 9 decimals.
     */
    function _toAgnostic(uint256 amount_) internal view returns ( uint256 ) {
        return amount_
            * 1e9
            / (IsOHM(sOHM).index());
    }

    /**
        @notice Convert agnostic value at current index to flat sOHM value
        @dev Agnostic value earns rebases. Agnostic value is amount / rebase_index.
             1e9 is because sOHM has 9 decimals.
     */
    function _fromAgnostic(uint256 amount_) internal view returns ( uint256 ) {
        return amount_
            * (IsOHM(sOHM).index())
            / 1e9;
    }

    /**
        @notice Convert flat sOHM value to agnostic value at a given index value
        @dev Agnostic value earns rebases. Agnostic value is amount / rebase_index.
             1e9 is because sOHM has 9 decimals.
     */
    function _fromAgnosticAtIndex(uint256 amount_, uint256 index_) internal pure returns ( uint256 ) {
        return amount_
            * index_
            / 1e9;
    }

    /************************
    * Emergency Functions
    ************************/

    function emergencyShutdown(bool active_) external onlyGovernor {
        depositDisabled = active_;
        withdrawDisabled = active_;
        redeemDisabled = active_;
        emit EmergencyShutdown(active_);
    }

    function disableDeposits(bool active_) external onlyGovernor {
        depositDisabled = active_;
    }

    function disableWithdrawals(bool active_) external onlyGovernor {
        withdrawDisabled = active_;
    }

    function disableRedeems(bool active_) external onlyGovernor {
        redeemDisabled = active_;
    }
}
// File: contracts/interfaces/IERC20.sol



// SPDX-License-Identifier: AGPL-3.0-or-later
pragma solidity >=0.7.5;

interface IERC20 {
  function totalSupply() external view returns (uint256);

  function balanceOf(address account) external view returns (uint256);

  function transfer(address recipient, uint256 amount) external returns (bool);

  function allowance(address owner, address spender) external view returns (uint256);

  function approve(address spender, uint256 amount) external returns (bool);

  function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);

  event Transfer(address indexed from, address indexed to, uint256 value);

  event Approval(address indexed owner, address indexed spender, uint256 value);
}

// File: contracts/interfaces/IsOHM.sol



// SPDX-License-Identifier: AGPL-3.0-or-later
pragma solidity >=0.7.5;

import "./IERC20.sol";

interface IsOHM is IERC20 {
    function rebase( uint256 ohmProfit_, uint epoch_) external returns (uint256);

    function circulatingSupply() external view returns (uint256);

    function gonsForBalance( uint amount ) external view returns ( uint );

    function balanceForGons( uint gons ) external view returns ( uint );

    function index() external view returns ( uint );

    function toG(uint amount) external view returns (uint);

    function fromG(uint amount) external view returns (uint);

     function changeDebt(
        uint256 amount,
        address debtor,
        bool add
    ) external;

    function debtBalances(address _address) external view returns (uint256);

}

// File: contracts/libraries/SafeERC20.sol



// SPDX-License-Identifier: AGPL-3.0-only
pragma solidity >=0.7.5;

import {IERC20} from "../interfaces/IERC20.sol";

/// @notice Safe IERC20 and ETH transfer library that safely handles missing return values.
/// @author Modified from Uniswap (https://github.com/Uniswap/uniswap-v3-periphery/blob/main/contracts/libraries/TransferHelper.sol)
/// Taken from Solmate
library SafeERC20 {
    function safeTransferFrom(
        IERC20 token,
        address from,
        address to,
        uint256 amount
    ) internal {
        (bool success, bytes memory data) = address(token).call(
            abi.encodeWithSelector(IERC20.transferFrom.selector, from, to, amount)
        );

        require(success && (data.length == 0 || abi.decode(data, (bool))), "TRANSFER_FROM_FAILED");
    }

    function safeTransfer(
        IERC20 token,
        address to,
        uint256 amount
    ) internal {
        (bool success, bytes memory data) = address(token).call(
            abi.encodeWithSelector(IERC20.transfer.selector, to, amount)
        );

        require(success && (data.length == 0 || abi.decode(data, (bool))), "TRANSFER_FAILED");
    }

    function safeApprove(
        IERC20 token,
        address to,
        uint256 amount
    ) internal {
        (bool success, bytes memory data) = address(token).call(
            abi.encodeWithSelector(IERC20.approve.selector, to, amount)
        );

        require(success && (data.length == 0 || abi.decode(data, (bool))), "APPROVE_FAILED");
    }

    function safeTransferETH(address to, uint256 amount) internal {
        (bool success, ) = to.call{value: amount}(new bytes(0));

        require(success, "ETH_TRANSFER_FAILED");
    }
}
// File: contracts/interfaces/IYieldDirector.sol



// SPDX-License-Identifier: AGPL-3.0-or-later
pragma solidity >=0.7.5;

interface IYieldDirector {
	function deposit(uint amount_, address recipient_) external;
	function withdraw(uint amount_, address recipient_) external;
	function withdrawAll() external;
	function depositsTo(address donor_, address recipient_) external view returns ( uint256 );
    function getAllDeposits(address donor_) external view returns ( address[] memory, uint256[] memory );
	function totalDeposits(address donor_) external view returns ( uint256 );
	function donatedTo(address donor_, address recipient_) external view returns ( uint256 );
	function totalDonated(address donor_) external view returns ( uint256 );
	function redeem() external;
	function redeemableBalance(address recipient_) external view returns ( uint256 );
}
// File: contracts/types/OlympusAccessControlled.sol



// SPDX-License-Identifier: AGPL-3.0-only
pragma solidity >=0.7.5;

import "../interfaces/IOlympusAuthority.sol";

abstract contract OlympusAccessControlled {

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

    event AuthorityUpdated(IOlympusAuthority indexed authority);

    string UNAUTHORIZED = "UNAUTHORIZED"; // save gas

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

    IOlympusAuthority public authority;


    /* ========== Constructor ========== */

    constructor(IOlympusAuthority _authority) {
        authority = _authority;
        emit AuthorityUpdated(_authority);
    }
    

    /* ========== MODIFIERS ========== */
    
    modifier onlyGovernor() {
        require(msg.sender == authority.governor(), UNAUTHORIZED);
        _;
    }
    
    modifier onlyGuardian() {
        require(msg.sender == authority.guardian(), UNAUTHORIZED);
        _;
    }
    
    modifier onlyPolicy() {
        require(msg.sender == authority.policy(), UNAUTHORIZED);
        _;
    }

    modifier onlyVault() {
        require(msg.sender == authority.vault(), UNAUTHORIZED);
        _;
    }
    
    /* ========== GOV ONLY ========== */
    
    function setAuthority(IOlympusAuthority _newAuthority) external onlyGovernor {
        authority = _newAuthority;
        emit AuthorityUpdated(_newAuthority);
    }
}

// File: contracts/interfaces/IOlympusAuthority.sol



// SPDX-License-Identifier: AGPL-3.0-or-later
pragma solidity >=0.7.5;

interface IOlympusAuthority {
    /* ========== EVENTS ========== */
    
    event GovernorPushed(address indexed from, address indexed to, bool _effectiveImmediately);
    event GuardianPushed(address indexed from, address indexed to, bool _effectiveImmediately);    
    event PolicyPushed(address indexed from, address indexed to, bool _effectiveImmediately);    
    event VaultPushed(address indexed from, address indexed to, bool _effectiveImmediately);    

    event GovernorPulled(address indexed from, address indexed to);
    event GuardianPulled(address indexed from, address indexed to);
    event PolicyPulled(address indexed from, address indexed to);
    event VaultPulled(address indexed from, address indexed to);

    /* ========== VIEW ========== */
    
    function governor() external view returns (address);
    function guardian() external view returns (address);
    function policy() external view returns (address);
    function vault() external view returns (address);
}