// File: contracts/lending/VotingVault.sol



// SPDX-License-Identifier: MIT
pragma solidity 0.8.9;

//import "../_external/IWETH.sol";

import "../IUSDI.sol";

import "./IVault.sol";
import "./IVaultController.sol";
import "./VotingVaultController.sol";

import "../_external/CompLike.sol";
import "../_external/IERC20.sol";
import "../_external/Context.sol";
import "../_external/openzeppelin/SafeERC20Upgradeable.sol";

contract VotingVault is Context {
  using SafeERC20Upgradeable for IERC20;

  /// @title VaultInfo struct
  /// @notice This vault holds the underlying token
  /// @notice The Capped token is held by the parent vault
  /// @notice Withdrawls must be initiated by the withdrawErc20() function on the parent vault


  /// @notice this struct is used to store the vault metadata
  /// this should reduce the cost of minting by ~15,000
  /// by limiting us to max 2**96-1 vaults
  struct VaultInfo {
    uint96 id;
    address vault_address;
  }
  /// @notice Metadata of vault, aka the id & the minter's address
  VaultInfo public _vaultInfo;

  VotingVaultController public _votingController;
  IVaultController public _controller;
  IVault public _parentVault;

  /// @notice checks if _msgSender is the controller of the voting vault
  modifier onlyVotingVaultController() {
    require(_msgSender() == address(_votingController), "sender not VotingVaultController");
    _;
  }
  /// @notice checks if _msgSender is the controller of the vault
  modifier onlyVaultController() {
    require(_msgSender() == address(_controller), "sender not VaultController");
    _;
  }
 /// @notice checks if _msgSender is the minter of the vault
  modifier onlyMinter() {
    require(_msgSender() == IVault(_vaultInfo.vault_address).minter(), "sender not minter");
    _;
  }

  /// @notice must be called by VotingVaultController, else it will not be registered as a vault in system
  /// @param id_ unique id of the vault, ever increasing and tracked by VaultController
  /// @param vault_address address of the vault this is attached to
  /// @param controller_address address of the vault controller
  /// @param voting_controller_address address of the voting vault controller
  constructor(
    uint96 id_,
    address vault_address,
    address controller_address,
    address voting_controller_address
  ) {
    _vaultInfo = VaultInfo(id_, vault_address);
    _controller = IVaultController(controller_address);
    _votingController = VotingVaultController(voting_controller_address);
    _parentVault = IVault(vault_address);
  }

  function parentVault() external view returns (address) {
    return address(_parentVault);
  }

  /// @notice id of the vault
  /// @return address of minter
  function id() external view  returns (uint96) {
    return _vaultInfo.id;
  }

  /// @notice delegate the voting power of a comp-like erc20 token to another address
  /// @param delegatee address that will receive the votes
  /// @param token_address address of comp-like erc20 token
  function delegateCompLikeTo(address delegatee, address token_address) external onlyMinter {
    CompLike(token_address).delegate(delegatee);
  }

  /// @notice function used by the VaultController to transfer tokens
  /// callable by the VaultController only
  /// @param _token token to transfer
  /// @param _to person to send the coins to
  /// @param _amount amount of coins to move
  function controllerTransfer(
    address _token,
    address _to,
    uint256 _amount
  ) external onlyVaultController {
    SafeERC20Upgradeable.safeTransfer(IERC20Upgradeable(_token), _to, _amount);
  }
  /// @notice function used by the VotingVaultController to transfer tokens
  /// callable by the VotingVaultController only
  /// @param _token token to transfer
  /// @param _to person to send the coins to
  /// @param _amount amount of coins to move
  function votingVaultControllerTransfer(
    address _token,
    address _to,
    uint256 _amount
  ) external onlyVotingVaultController {
    SafeERC20Upgradeable.safeTransfer(IERC20Upgradeable(_token), _to, _amount);
  }
}

// File: contracts/IUSDI.sol



// SPDX-License-Identifier: MIT
pragma solidity 0.8.9;

import "./_external/IERC20Metadata.sol";

/// @title USDI Events
/// @notice interface which contains any events which the USDI contract emits
interface USDIEvents {
  event Deposit(address indexed _from, uint256 _value);
  event Withdraw(address indexed _from, uint256 _value);
  event Mint(address to, uint256 _value);
  event Burn(address from, uint256 _value);
  event Donation(address indexed _from, uint256 _value, uint256 _totalSupply);
}

/// @title USDI Interface
/// @notice extends USDIEvents and IERC20Metadata
interface IUSDI is IERC20Metadata, USDIEvents {
  /// @notice initializer specifies the reserveAddress
  function initialize(address reserveAddress) external;

  // getters
  function reserveRatio() external view returns (uint192);

  function reserveAddress() external view returns (address);

  // owner
  function owner() external view returns (address);

  // business
  function deposit(uint256 usdc_amount) external;

  function depositTo(uint256 usdc_amount, address target) external;

  function withdraw(uint256 usdc_amount) external;

  function withdrawTo(uint256 usdc_amount, address target) external;

  function withdrawAll() external;

  function withdrawAllTo(address target) external;

  function donate(uint256 usdc_amount) external;

  function donateReserve() external;

  // admin functions

  function setPauser(address pauser_) external;

  function pauser() external view returns (address);

  function pause() external;

  function unpause() external;

  function mint(uint256 usdc_amount) external;

  function burn(uint256 usdc_amount) external;

  function setVaultController(address vault_master_address) external;

  function getVaultController() external view returns (address);

  // functions for the vault controller to call
  function vaultControllerBurn(address target, uint256 amount) external;

  function vaultControllerMint(address target, uint256 amount) external;

  function vaultControllerTransfer(address target, uint256 usdc_amount) external;

  function vaultControllerDonate(uint256 amount) external;
}

// File: contracts/lending/IVault.sol



// SPDX-License-Identifier: MIT
pragma solidity 0.8.9;

// @title Vault Events
/// @notice interface which contains any events which the Vault contract emits
interface VaultEvents {
  event Deposit(address token_address, uint256 amount);
  event Withdraw(address token_address, uint256 amount);
}

/// @title Vault Interface
/// @notice extends VaultEvents
interface IVault is VaultEvents {
  /// @notice value of _baseLiability
  function baseLiability() external view returns (uint256);
  /// @notice value of _vaultInfo.minter
  function minter() external view returns (address);
  /// @notice value of _vaultInfo.id
  function id() external view returns (uint96);
  /// @notice value of _tokenBalance
  function tokenBalance(address) external view returns (uint256);

  // business logic

  function withdrawErc20(address token_address, uint256 amount) external;
  function delegateCompLikeTo(address compLikeDelegatee, address compLikeToken) external;

  // administrative functions
  function controllerTransfer(
    address _token,
    address _to,
    uint256 _amount
  ) external;

  function modifyLiability(bool increase, uint256 base_amount) external returns (uint256);
}

// File: contracts/lending/IVaultController.sol



// SPDX-License-Identifier: MIT
pragma solidity 0.8.9;

// @title VaultController Events
/// @notice interface which contains any events which the VaultController contract emits
interface VaultControllerEvents {
  event InterestEvent(uint64 epoch, uint192 amount, uint256 curve_val);
  event NewProtocolFee(uint256 protocol_fee);
  event RegisteredErc20(address token_address, uint256 LTVe4, address oracle_address, uint256 liquidationIncentivee4);
  event UpdateRegisteredErc20(
    address token_address,
    uint256 LTVe4,
    address oracle_address,
    uint256 liquidationIncentivee4
  );
  event NewVault(address vault_address, uint256 vaultId, address vaultOwner);
  event RegisterOracleMaster(address oracleMasterAddress);
  event RegisterCurveMaster(address curveMasterAddress);
  event BorrowUSDi(uint256 vaultId, address vaultAddress, uint256 borrowAmount);
  event RepayUSDi(uint256 vaultId, address vaultAddress, uint256 repayAmount);
  event Liquidate(uint256 vaultId, address asset_address, uint256 usdi_to_repurchase, uint256 tokens_to_liquidate);
}

/// @title VaultController Interface
/// @notice extends VaultControllerEvents
interface IVaultController is VaultControllerEvents {
  // initializer
  function initialize() external;

  // view functions

  function tokensRegistered() external view returns (uint256);

  function vaultsMinted() external view returns (uint96);

  function lastInterestTime() external view returns (uint64);

  function totalBaseLiability() external view returns (uint192);

  function interestFactor() external view returns (uint192);

  function protocolFee() external view returns (uint192);

  function vaultAddress(uint96 id) external view returns (address);

  function vaultIDs(address wallet) external view returns (uint96[] memory);

  function amountToSolvency(uint96 id) external view returns (uint256);

  function vaultLiability(uint96 id) external view returns (uint192);

  function vaultBorrowingPower(uint96 id) external view returns (uint192);

  function tokensToLiquidate(uint96 id, address token) external view returns (uint256);

  function checkVault(uint96 id) external view returns (bool);

  struct VaultSummary {
    uint96 id;
    uint192 borrowingPower;
    uint192 vaultLiability;
    address[] tokenAddresses;
    uint256[] tokenBalances;
  }

  function vaultSummaries(uint96 start, uint96 stop) external view returns (VaultSummary[] memory);

  // interest calculations
  function calculateInterest() external returns (uint256);

  // vault management business
  function mintVault() external returns (address);

  function liquidateVault(
    uint96 id,
    address asset_address,
    uint256 tokenAmount
  ) external returns (uint256);

  function borrowUsdi(uint96 id, uint192 amount) external;

  function borrowUSDIto(
    uint96 id,
    uint192 amount,
    address target
  ) external;

  function borrowUSDCto(
    uint96 id,
    uint192 usdc_amount,
    address target
  ) external;

  function repayUSDi(uint96 id, uint192 amount) external;

  function repayAllUSDi(uint96 id) external;

  // admin
  function pause() external;

  function unpause() external;

  function getOracleMaster() external view returns (address);

  function registerOracleMaster(address master_oracle_address) external;

  function getCurveMaster() external view returns (address);

  function registerCurveMaster(address master_curve_address) external;

  function changeProtocolFee(uint192 new_protocol_fee) external;

  function registerErc20(
    address token_address,
    uint256 LTV,
    address oracle_address,
    uint256 liquidationIncentive
  ) external;

  function registerUSDi(address usdi_address) external;

  function updateRegisteredErc20(
    address token_address,
    uint256 LTV,
    address oracle_address,
    uint256 liquidationIncentive
  ) external;
}

// File: contracts/lending/VotingVaultController.sol



// SPDX-License-Identifier: MIT
pragma solidity 0.8.9;

import "../_external/IERC20Metadata.sol";
import "../_external/openzeppelin/ERC20Upgradeable.sol";
import "../_external/openzeppelin/OwnableUpgradeable.sol";
import "../_external/openzeppelin/Initializable.sol";

import "./IVaultController.sol";
import "./VotingVault.sol";

/// @title CappedGovToken
/// @notice handles all minting/burning of underlying
/// @dev extends ierc20 upgradable
contract VotingVaultController is Initializable, OwnableUpgradeable {
  uint8 private _underlying_decimals;
  IVaultController public _vaultController;

  mapping(address => uint96) public _vaultAddress_vaultId;
  mapping(uint96 => address) public _vaultId_votingVaultAddress;
  mapping(address => uint96) public _votingVaultAddress_vaultId;

  mapping(address => address) public _underlying_CappedToken;
  mapping(address => address) public _CappedToken_underlying;

  /// @notice initializer for contract
  /// @param vaultController_ the address of the vault controller
  function initialize(address vaultController_) public initializer {
    __Ownable_init();
    _vaultController = IVaultController(vaultController_);
  }

  /// @notice register an underlying capped token pair
  /// note that registring a token as a capepd token allows it to transfer the balance of the corresponding token at will
  /// @param underlying_address address of underlying
  /// @param capped_token address of capped token
  function registerUnderlying(address underlying_address, address capped_token) external onlyOwner {
    _underlying_CappedToken[underlying_address] = capped_token;
    _CappedToken_underlying[capped_token] = underlying_address;
  }

  function retrieveUnderlying(
    uint256 amount,
    address voting_vault,
    address target
  ) public {
    require(voting_vault != address(0x0), "invalid vault");

    address underlying_address = _CappedToken_underlying[_msgSender()];

    require(underlying_address != address(0x0), "only capped token");
    VotingVault votingVault = VotingVault(voting_vault);
    votingVault.votingVaultControllerTransfer(underlying_address, target, amount);
  }

  event NewVotingVault(address voting_vault_address, uint256 vaultId);

  /// @notice create a new vault
  /// @param id of an existing vault
  /// @return address of the new vault
  function mintVault(uint96 id) public returns (address) {
    if (_vaultId_votingVaultAddress[id] == address(0)) {
      address vault_address = _vaultController.vaultAddress(id);
      if (vault_address != address(0)) {
        // mint the vault itself, deploying the contract
        address voting_vault_address = address(
          new VotingVault(id, vault_address, address(_vaultController), address(this))
        );
        // add the vault to our system
        _vaultId_votingVaultAddress[id] = voting_vault_address;
        _vaultAddress_vaultId[vault_address] = id;
        _votingVaultAddress_vaultId[voting_vault_address] = id;
        // emit the event
        emit NewVotingVault(voting_vault_address, id);
      }
    }
    return _vaultId_votingVaultAddress[id];
  }

  function votingVaultId(address voting_vault_address) public view returns (uint96) {
    return _votingVaultAddress_vaultId[voting_vault_address];
  }

  function vaultId(address vault_address) public view returns (uint96) {
    return _vaultAddress_vaultId[vault_address];
  }

  function votingVaultAddress(uint96 vault_id) public view returns (address) {
    return _vaultId_votingVaultAddress[vault_id];
  }
}

// File: contracts/_external/CompLike.sol



// SPDX-License-Identifier: MIT
pragma solidity 0.8.9;

interface CompLike {
  function delegate(address delegatee) external;
}

// File: contracts/_external/IERC20.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.8.9;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
  /**
   * @dev Returns the amount of tokens in existence.
   */
  function totalSupply() external view returns (uint256);

  /**
   * @dev Returns the token decimals.
   */
  function decimals() external view returns (uint8);

  /**
   * @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 `recipient`.
   *
   * Returns a boolean value indicating whether the operation succeeded.
   *
   * Emits a {Transfer} event.
   */
  function transfer(address recipient, 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 `sender` to `recipient` 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 sender,
    address recipient,
    uint256 amount
  ) external returns (bool);

  /**
   * @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);
}

// File: contracts/_external/Context.sol



// SPDX-License-Identifier: MIT
pragma solidity 0.8.9;

/*
 * @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) {
    this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
    return msg.data;
  }
}

// File: contracts/_external/openzeppelin/SafeERC20Upgradeable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/utils/SafeERC20.sol)

pragma solidity ^0.8.0;

import "./IERC20Upgradeable.sol";
import "./AddressUpgradeable.sol";

/**
 * @title SafeERC20
 * @dev Wrappers around ERC20 operations that throw on failure (when the token
 * contract returns false). Tokens that return no value (and instead revert or
 * throw on failure) are also supported, non-reverting calls are assumed to be
 * successful.
 * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
 * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
 */
library SafeERC20Upgradeable {
    using AddressUpgradeable for address;

    function safeTransfer(
        IERC20Upgradeable token,
        address to,
        uint256 value
    ) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }

    function safeTransferFrom(
        IERC20Upgradeable token,
        address from,
        address to,
        uint256 value
    ) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }

    /**
     * @dev Deprecated. This function has issues similar to the ones found in
     * {IERC20-approve}, and its usage is discouraged.
     *
     * Whenever possible, use {safeIncreaseAllowance} and
     * {safeDecreaseAllowance} instead.
     */
    function safeApprove(
        IERC20Upgradeable token,
        address spender,
        uint256 value
    ) internal {
        // safeApprove should only be called when setting an initial allowance,
        // or when resetting it to zero. To increase and decrease it, use
        // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
        require(
            (value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeERC20: approve from non-zero to non-zero allowance"
        );
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
    }

    function safeIncreaseAllowance(
        IERC20Upgradeable token,
        address spender,
        uint256 value
    ) internal {
        uint256 newAllowance = token.allowance(address(this), spender) + value;
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }

    function safeDecreaseAllowance(
        IERC20Upgradeable token,
        address spender,
        uint256 value
    ) internal {
        unchecked {
            uint256 oldAllowance = token.allowance(address(this), spender);
            require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
            uint256 newAllowance = oldAllowance - value;
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
        }
    }

    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     */
    function _callOptionalReturn(IERC20Upgradeable token, bytes memory data) private {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
        // the target address contains contract code and also asserts for success in the low-level call.

        bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
        if (returndata.length > 0) {
            // Return data is optional
            require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
        }
    }
}
// File: contracts/_external/IERC20Metadata.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.8.9;

import "./IERC20.sol";

/**
 * @dev Interface for the optional metadata functions from the ERC20 standard.
 *
 * _Available since v4.1._
 */
interface IERC20Metadata is IERC20 {
  /**
   * @dev Returns the name of the token.
   */
  function name() external view returns (string memory);

  /**
   * @dev Returns the symbol of the token.
   */
  function symbol() external view returns (string memory);

  /**
   * @dev Returns the decimals places of the token.
   */
  function decimals() external view returns (uint8);
}

// File: contracts/_external/openzeppelin/ERC20Upgradeable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.0 (token/ERC20/ERC20.sol)

pragma solidity 0.8.9;

import "./IERC20Upgradeable.sol";
import "./IERC20MetadataUpgradeable.sol";
import "./ContextUpgradeable.sol";
import "./Initializable.sol";

/**
 * @dev Implementation of the {IERC20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 * For a generic mechanism see {ERC20PresetMinterPauser}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * We have followed general OpenZeppelin Contracts guidelines: functions revert
 * instead returning `false` on failure. This behavior is nonetheless
 * conventional and does not conflict with the expectations of ERC20
 * applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 *
 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
 * functions have been added to mitigate the well-known issues around setting
 * allowances. See {IERC20-approve}.
 */
contract ERC20Upgradeable is Initializable, ContextUpgradeable, IERC20Upgradeable, IERC20MetadataUpgradeable {
  mapping(address => uint256) private _balances;

  mapping(address => mapping(address => uint256)) private _allowances;

  uint256 private _totalSupply;

  string private _name;
  string private _symbol;

  /**
   * @dev Sets the values for {name} and {symbol}.
   *
   * The default value of {decimals} is 18. To select a different value for
   * {decimals} you should overload it.
   *
   * All two of these values are immutable: they can only be set once during
   * construction.
   */
  function __ERC20_init(string memory name_, string memory symbol_) internal initializer {
    __Context_init_unchained();
    __ERC20_init_unchained(name_, symbol_);
  }

  function __ERC20_init_unchained(string memory name_, string memory symbol_) internal initializer {
    _name = name_;
    _symbol = symbol_;
  }

  /**
   * @dev Returns the name of the token.
   */
  function name() public view virtual override returns (string memory) {
    return _name;
  }

  /**
   * @dev Returns the symbol of the token, usually a shorter version of the
   * name.
   */
  function symbol() public view virtual override returns (string memory) {
    return _symbol;
  }

  /**
   * @dev Returns the number of decimals used to get its user representation.
   * For example, if `decimals` equals `2`, a balance of `505` tokens should
   * be displayed to a user as `5.05` (`505 / 10 ** 2`).
   *
   * Tokens usually opt for a value of 18, imitating the relationship between
   * Ether and Wei. This is the value {ERC20} uses, unless this function is
   * overridden;
   *
   * NOTE: This information is only used for _display_ purposes: it in
   * no way affects any of the arithmetic of the contract, including
   * {IERC20-balanceOf} and {IERC20-transfer}.
   */
  function decimals() public view virtual override returns (uint8) {
    return 18;
  }

  /**
   * @dev See {IERC20-totalSupply}.
   */
  function totalSupply() public view virtual override returns (uint256) {
    return _totalSupply;
  }

  /**
   * @dev See {IERC20-balanceOf}.
   */
  function balanceOf(address account) public view virtual override returns (uint256) {
    return _balances[account];
  }

  /**
   * @dev See {IERC20-transfer}.
   *
   * Requirements:
   *
   * - `recipient` cannot be the zero address.
   * - the caller must have a balance of at least `amount`.
   */
  function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
    _transfer(_msgSender(), recipient, amount);
    return true;
  }

  /**
   * @dev See {IERC20-allowance}.
   */
  function allowance(address owner, address spender) public view virtual override returns (uint256) {
    return _allowances[owner][spender];
  }

  /**
   * @dev See {IERC20-approve}.
   *
   * Requirements:
   *
   * - `spender` cannot be the zero address.
   */
  function approve(address spender, uint256 amount) public virtual override returns (bool) {
    _approve(_msgSender(), spender, amount);
    return true;
  }

  /**
   * @dev See {IERC20-transferFrom}.
   *
   * Emits an {Approval} event indicating the updated allowance. This is not
   * required by the EIP. See the note at the beginning of {ERC20}.
   *
   * Requirements:
   *
   * - `sender` and `recipient` cannot be the zero address.
   * - `sender` must have a balance of at least `amount`.
   * - the caller must have allowance for ``sender``'s tokens of at least
   * `amount`.
   */
  function transferFrom(
    address sender,
    address recipient,
    uint256 amount
  ) public virtual override returns (bool) {
    _transfer(sender, recipient, amount);

    uint256 currentAllowance = _allowances[sender][_msgSender()];
    require(currentAllowance >= amount, "ERC20: transfer amount exceeds allowance");
    unchecked {
      _approve(sender, _msgSender(), currentAllowance - amount);
    }

    return true;
  }

  /**
   * @dev Atomically increases the allowance granted to `spender` by the caller.
   *
   * This is an alternative to {approve} that can be used as a mitigation for
   * problems described in {IERC20-approve}.
   *
   * Emits an {Approval} event indicating the updated allowance.
   *
   * Requirements:
   *
   * - `spender` cannot be the zero address.
   */
  function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
    _approve(_msgSender(), spender, _allowances[_msgSender()][spender] + addedValue);
    return true;
  }

  /**
   * @dev Atomically decreases the allowance granted to `spender` by the caller.
   *
   * This is an alternative to {approve} that can be used as a mitigation for
   * problems described in {IERC20-approve}.
   *
   * Emits an {Approval} event indicating the updated allowance.
   *
   * Requirements:
   *
   * - `spender` cannot be the zero address.
   * - `spender` must have allowance for the caller of at least
   * `subtractedValue`.
   */
  function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
    uint256 currentAllowance = _allowances[_msgSender()][spender];
    require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
    unchecked {
      _approve(_msgSender(), spender, currentAllowance - subtractedValue);
    }

    return true;
  }

  /**
   * @dev Moves `amount` of tokens from `sender` to `recipient`.
   *
   * This internal function is equivalent to {transfer}, and can be used to
   * e.g. implement automatic token fees, slashing mechanisms, etc.
   *
   * Emits a {Transfer} event.
   *
   * Requirements:
   *
   * - `sender` cannot be the zero address.
   * - `recipient` cannot be the zero address.
   * - `sender` must have a balance of at least `amount`.
   */
  function _transfer(
    address sender,
    address recipient,
    uint256 amount
  ) internal virtual {
    require(sender != address(0), "ERC20: transfer from the zero address");
    require(recipient != address(0), "ERC20: transfer to the zero address");

    _beforeTokenTransfer(sender, recipient, amount);

    uint256 senderBalance = _balances[sender];
    require(senderBalance >= amount, "ERC20: transfer amount exceeds balance");
    unchecked {
      _balances[sender] = senderBalance - amount;
    }
    _balances[recipient] += amount;

    emit Transfer(sender, recipient, amount);

    _afterTokenTransfer(sender, recipient, amount);
  }

  /** @dev Creates `amount` tokens and assigns them to `account`, increasing
   * the total supply.
   *
   * Emits a {Transfer} event with `from` set to the zero address.
   *
   * Requirements:
   *
   * - `account` cannot be the zero address.
   */
  function _mint(address account, uint256 amount) internal virtual {
    require(account != address(0), "ERC20: mint to the zero address");

    _beforeTokenTransfer(address(0), account, amount);

    _totalSupply += amount;
    _balances[account] += amount;
    emit Transfer(address(0), account, amount);

    _afterTokenTransfer(address(0), account, amount);
  }

  /**
   * @dev Destroys `amount` tokens from `account`, reducing the
   * total supply.
   *
   * Emits a {Transfer} event with `to` set to the zero address.
   *
   * Requirements:
   *
   * - `account` cannot be the zero address.
   * - `account` must have at least `amount` tokens.
   */
  function _burn(address account, uint256 amount) internal virtual {
    require(account != address(0), "ERC20: burn from the zero address");

    _beforeTokenTransfer(account, address(0), amount);

    uint256 accountBalance = _balances[account];
    require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
    unchecked {
      _balances[account] = accountBalance - amount;
    }
    _totalSupply -= amount;

    emit Transfer(account, address(0), amount);

    _afterTokenTransfer(account, address(0), amount);
  }

  /**
   * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
   *
   * This internal function is equivalent to `approve`, and can be used to
   * e.g. set automatic allowances for certain subsystems, etc.
   *
   * Emits an {Approval} event.
   *
   * Requirements:
   *
   * - `owner` cannot be the zero address.
   * - `spender` cannot be the zero address.
   */
  function _approve(
    address owner,
    address spender,
    uint256 amount
  ) internal virtual {
    require(owner != address(0), "ERC20: approve from the zero address");
    require(spender != address(0), "ERC20: approve to the zero address");

    _allowances[owner][spender] = amount;
    emit Approval(owner, spender, amount);
  }

  /**
   * @dev Hook that is called before any transfer of tokens. This includes
   * minting and burning.
   *
   * Calling conditions:
   *
   * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
   * will be transferred to `to`.
   * - when `from` is zero, `amount` tokens will be minted for `to`.
   * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
   * - `from` and `to` are never both zero.
   *
   * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
   */
  function _beforeTokenTransfer(
    address from,
    address to,
    uint256 amount
  ) internal virtual {}

  /**
   * @dev Hook that is called after any transfer of tokens. This includes
   * minting and burning.
   *
   * Calling conditions:
   *
   * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
   * has been transferred to `to`.
   * - when `from` is zero, `amount` tokens have been minted for `to`.
   * - when `to` is zero, `amount` of ``from``'s tokens have been burned.
   * - `from` and `to` are never both zero.
   *
   * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
   */
  function _afterTokenTransfer(
    address from,
    address to,
    uint256 amount
  ) internal virtual {}

  uint256[45] private __gap;
}

// File: contracts/_external/openzeppelin/OwnableUpgradeable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.0 (access/Ownable.sol)

pragma solidity 0.8.9;

import "./ContextUpgradeable.sol";
import "./Initializable.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 OwnableUpgradeable is Initializable, ContextUpgradeable {
  address private _owner;

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

  /**
   * @dev Initializes the contract setting the deployer as the initial owner.
   */
  function __Ownable_init() internal initializer {
    __Context_init_unchained();
    __Ownable_init_unchained();
  }

  function __Ownable_init_unchained() internal initializer {
    _transferOwnership(_msgSender());
  }

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

  /**
   * @dev Throws if called by any account other than the owner.
   */
  modifier onlyOwner() {
    require(owner() == _msgSender(), "Ownable: caller is not the owner");
    _;
  }

  /**
   * @dev Leaves the contract without owner. It will not be possible to call
   * `onlyOwner` functions anymore. Can only be called by the current owner.
   *
   * NOTE: Renouncing ownership will leave the contract without an owner,
   * thereby removing 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);
  }

  uint256[49] private __gap;
}

// File: contracts/_external/openzeppelin/Initializable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.0 (proxy/utils/Initializable.sol)

pragma solidity 0.8.9;

/**
 * @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
 * behind a proxy. Since proxied contracts do not make use of a constructor, it's common to move constructor logic to an
 * external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
 * function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
 *
 * TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
 * possible by providing the encoded function call as the `_data` argument to {ERC1967Proxy-constructor}.
 *
 * CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
 * that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
 *
 * [CAUTION]
 * ====
 * Avoid leaving a contract uninitialized.
 *
 * An uninitialized contract can be taken over by an attacker. This applies to both a proxy and its implementation
 * contract, which may impact the proxy. To initialize the implementation contract, you can either invoke the
 * initializer manually, or you can include a constructor to automatically mark it as initialized when it is deployed:
 *
 * [.hljs-theme-light.nopadding]
 * ```
 * /// @custom:oz-upgrades-unsafe-allow constructor
 * constructor() initializer {}
 * ```
 * ====
 */
abstract contract Initializable {
  /**
   * @dev Indicates that the contract has been initialized.
   */
  bool private _initialized;

  /**
   * @dev Indicates that the contract is in the process of being initialized.
   */
  bool private _initializing;

  /**
   * @dev Modifier to protect an initializer function from being invoked twice.
   */
  modifier initializer() {
    require(_initializing || !_initialized, "Initializable: contract is already initialized");

    bool isTopLevelCall = !_initializing;
    if (isTopLevelCall) {
      _initializing = true;
      _initialized = true;
    }

    _;

    if (isTopLevelCall) {
      _initializing = false;
    }
  }
  /**
   * @dev Modifier to protect an initialization function so that it can only be invoked by functions with the
   * {initializer} modifier, directly or indirectly.
   */
  modifier onlyInitializing() {
    require(_initializing, "Initializable: contract is not initializing");
    _;
  }
}

// File: contracts/_external/openzeppelin/IERC20Upgradeable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.0 (token/ERC20/IERC20.sol)

pragma solidity 0.8.9;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20Upgradeable {
  /**
   * @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 `recipient`.
   *
   * Returns a boolean value indicating whether the operation succeeded.
   *
   * Emits a {Transfer} event.
   */
  function transfer(address recipient, 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 `sender` to `recipient` 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 sender,
    address recipient,
    uint256 amount
  ) external returns (bool);

  /**
   * @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);
}

// File: contracts/_external/openzeppelin/IERC20MetadataUpgradeable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.0 (token/ERC20/extensions/IERC20Metadata.sol)

pragma solidity 0.8.9;

import "./IERC20Upgradeable.sol";

/**
 * @dev Interface for the optional metadata functions from the ERC20 standard.
 *
 * _Available since v4.1._
 */
interface IERC20MetadataUpgradeable is IERC20Upgradeable {
  /**
   * @dev Returns the name of the token.
   */
  function name() external view returns (string memory);

  /**
   * @dev Returns the symbol of the token.
   */
  function symbol() external view returns (string memory);

  /**
   * @dev Returns the decimals places of the token.
   */
  function decimals() external view returns (uint8);
}

// File: contracts/_external/openzeppelin/ContextUpgradeable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.0 (utils/Context.sol)

pragma solidity 0.8.9;
import "./Initializable.sol";

/**
 * @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 ContextUpgradeable is Initializable {
  function __Context_init() internal initializer {
    __Context_init_unchained();
  }

  function __Context_init_unchained() internal initializer {}

  function _msgSender() internal view virtual returns (address) {
    return msg.sender;
  }

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

  uint256[50] private __gap;
}

// File: contracts/_external/openzeppelin/AddressUpgradeable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.0 (utils/Address.sol)

pragma solidity 0.8.9;

/**
 * @dev Collection of functions related to the address type
 */
library AddressUpgradeable {
  /**
   * @dev Returns true if `account` is a contract.
   *
   * [IMPORTANT]
   * ====
   * It is unsafe to assume that an address for which this function returns
   * false is an externally-owned account (EOA) and not a contract.
   *
   * Among others, `isContract` will return false for the following
   * types of addresses:
   *
   *  - an externally-owned account
   *  - a contract in construction
   *  - an address where a contract will be created
   *  - an address where a contract lived, but was destroyed
   * ====
   */
  function isContract(address account) internal view returns (bool) {
    // This method relies on extcodesize, which returns 0 for contracts in
    // construction, since the code is only stored at the end of the
    // constructor execution.

    uint256 size;
    assembly {
      size := extcodesize(account)
    }
    return size > 0;
  }

  /**
   * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
   * `recipient`, forwarding all available gas and reverting on errors.
   *
   * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
   * of certain opcodes, possibly making contracts go over the 2300 gas limit
   * imposed by `transfer`, making them unable to receive funds via
   * `transfer`. {sendValue} removes this limitation.
   *
   * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
   *
   * IMPORTANT: because control is transferred to `recipient`, care must be
   * taken to not create reentrancy vulnerabilities. Consider using
   * {ReentrancyGuard} or the
   * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
   */
  function sendValue(address payable recipient, uint256 amount) internal {
    require(address(this).balance >= amount, "Address: insufficient balance");

    (bool success, ) = recipient.call{value: amount}("");
    require(success, "Address: unable to send value, recipient may have reverted");
  }

  /**
   * @dev Performs a Solidity function call using a low level `call`. A
   * plain `call` is an unsafe replacement for a function call: use this
   * function instead.
   *
   * If `target` reverts with a revert reason, it is bubbled up by this
   * function (like regular Solidity function calls).
   *
   * Returns the raw returned data. To convert to the expected return value,
   * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
   *
   * Requirements:
   *
   * - `target` must be a contract.
   * - calling `target` with `data` must not revert.
   *
   * _Available since v3.1._
   */
  function functionCall(address target, bytes memory data) internal returns (bytes memory) {
    return functionCall(target, data, "Address: low-level call failed");
  }

  /**
   * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
   * `errorMessage` as a fallback revert reason when `target` reverts.
   *
   * _Available since v3.1._
   */
  function functionCall(
    address target,
    bytes memory data,
    string memory errorMessage
  ) internal returns (bytes memory) {
    return functionCallWithValue(target, data, 0, errorMessage);
  }

  /**
   * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
   * but also transferring `value` wei to `target`.
   *
   * Requirements:
   *
   * - the calling contract must have an ETH balance of at least `value`.
   * - the called Solidity function must be `payable`.
   *
   * _Available since v3.1._
   */
  function functionCallWithValue(
    address target,
    bytes memory data,
    uint256 value
  ) internal returns (bytes memory) {
    return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
  }

  /**
   * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
   * with `errorMessage` as a fallback revert reason when `target` reverts.
   *
   * _Available since v3.1._
   */
  function functionCallWithValue(
    address target,
    bytes memory data,
    uint256 value,
    string memory errorMessage
  ) internal returns (bytes memory) {
    require(address(this).balance >= value, "Address: insufficient balance for call");
    require(isContract(target), "Address: call to non-contract");

    (bool success, bytes memory returndata) = target.call{value: value}(data);
    return verifyCallResult(success, returndata, errorMessage);
  }

  /**
   * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
   * but performing a static call.
   *
   * _Available since v3.3._
   */
  function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
    return functionStaticCall(target, data, "Address: low-level static call failed");
  }

  /**
   * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
   * but performing a static call.
   *
   * _Available since v3.3._
   */
  function functionStaticCall(
    address target,
    bytes memory data,
    string memory errorMessage
  ) internal view returns (bytes memory) {
    require(isContract(target), "Address: static call to non-contract");

    (bool success, bytes memory returndata) = target.staticcall(data);
    return verifyCallResult(success, returndata, errorMessage);
  }

  /**
   * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
   * revert reason using the provided one.
   *
   * _Available since v4.3._
   */
  function verifyCallResult(
    bool success,
    bytes memory returndata,
    string memory errorMessage
  ) internal pure returns (bytes memory) {
    if (success) {
      return returndata;
    } else {
      // Look for revert reason and bubble it up if present
      if (returndata.length > 0) {
        // The easiest way to bubble the revert reason is using memory via assembly

        assembly {
          let returndata_size := mload(returndata)
          revert(add(32, returndata), returndata_size)
        }
      } else {
        revert(errorMessage);
      }
    }
  }
}