// File: @chainlink/contracts/src/v0.8/interfaces/AggregatorV3Interface.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

interface AggregatorV3Interface {
  function decimals() external view returns (uint8);

  function description() external view returns (string memory);

  function version() external view returns (uint256);

  function getRoundData(uint80 _roundId)
    external
    view
    returns (
      uint80 roundId,
      int256 answer,
      uint256 startedAt,
      uint256 updatedAt,
      uint80 answeredInRound
    );

  function latestRoundData()
    external
    view
    returns (
      uint80 roundId,
      int256 answer,
      uint256 startedAt,
      uint256 updatedAt,
      uint80 answeredInRound
    );
}

// File: @openzeppelin/contracts-upgradeable/access/IAccessControlUpgradeable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (access/IAccessControl.sol)

pragma solidity ^0.8.0;

/**
 * @dev External interface of AccessControl declared to support ERC165 detection.
 */
interface IAccessControlUpgradeable {
    /**
     * @dev Emitted when `newAdminRole` is set as ``role``'s admin role, replacing `previousAdminRole`
     *
     * `DEFAULT_ADMIN_ROLE` is the starting admin for all roles, despite
     * {RoleAdminChanged} not being emitted signaling this.
     *
     * _Available since v3.1._
     */
    event RoleAdminChanged(bytes32 indexed role, bytes32 indexed previousAdminRole, bytes32 indexed newAdminRole);

    /**
     * @dev Emitted when `account` is granted `role`.
     *
     * `sender` is the account that originated the contract call, an admin role
     * bearer except when using {AccessControl-_setupRole}.
     */
    event RoleGranted(bytes32 indexed role, address indexed account, address indexed sender);

    /**
     * @dev Emitted when `account` is revoked `role`.
     *
     * `sender` is the account that originated the contract call:
     *   - if using `revokeRole`, it is the admin role bearer
     *   - if using `renounceRole`, it is the role bearer (i.e. `account`)
     */
    event RoleRevoked(bytes32 indexed role, address indexed account, address indexed sender);

    /**
     * @dev Returns `true` if `account` has been granted `role`.
     */
    function hasRole(bytes32 role, address account) external view returns (bool);

    /**
     * @dev Returns the admin role that controls `role`. See {grantRole} and
     * {revokeRole}.
     *
     * To change a role's admin, use {AccessControl-_setRoleAdmin}.
     */
    function getRoleAdmin(bytes32 role) external view returns (bytes32);

    /**
     * @dev Grants `role` to `account`.
     *
     * If `account` had not been already granted `role`, emits a {RoleGranted}
     * event.
     *
     * Requirements:
     *
     * - the caller must have ``role``'s admin role.
     */
    function grantRole(bytes32 role, address account) external;

    /**
     * @dev Revokes `role` from `account`.
     *
     * If `account` had been granted `role`, emits a {RoleRevoked} event.
     *
     * Requirements:
     *
     * - the caller must have ``role``'s admin role.
     */
    function revokeRole(bytes32 role, address account) external;

    /**
     * @dev Revokes `role` from the calling account.
     *
     * Roles are often managed via {grantRole} and {revokeRole}: this function's
     * purpose is to provide a mechanism for accounts to lose their privileges
     * if they are compromised (such as when a trusted device is misplaced).
     *
     * If the calling account had been granted `role`, emits a {RoleRevoked}
     * event.
     *
     * Requirements:
     *
     * - the caller must be `account`.
     */
    function renounceRole(bytes32 role, address account) external;
}

// File: @openzeppelin/contracts-upgradeable/token/ERC20/extensions/draft-IERC20PermitUpgradeable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/draft-IERC20Permit.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
 * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
 *
 * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
 * presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
 * need to send a transaction, and thus is not required to hold Ether at all.
 */
interface IERC20PermitUpgradeable {
    /**
     * @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,
     * given ``owner``'s signed approval.
     *
     * IMPORTANT: The same issues {IERC20-approve} has related to transaction
     * ordering also apply here.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `deadline` must be a timestamp in the future.
     * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
     * over the EIP712-formatted function arguments.
     * - the signature must use ``owner``'s current nonce (see {nonces}).
     *
     * For more information on the signature format, see the
     * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
     * section].
     */
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external;

    /**
     * @dev Returns the current nonce for `owner`. This value must be
     * included whenever a signature is generated for {permit}.
     *
     * Every successful call to {permit} increases ``owner``'s nonce by one. This
     * prevents a signature from being used multiple times.
     */
    function nonces(address owner) external view returns (uint256);

    /**
     * @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.
     */
    // solhint-disable-next-line func-name-mixedcase
    function DOMAIN_SEPARATOR() external view returns (bytes32);
}

// File: @openzeppelin/contracts-upgradeable/token/ERC20/extensions/IERC20MetadataUpgradeable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol)

pragma solidity ^0.8.0;

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: @openzeppelin/contracts-upgradeable/token/ERC20/IERC20Upgradeable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20Upgradeable {
    /**
     * @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/metatx/ERC2771Context.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (metatx/ERC2771Context.sol)

pragma solidity ^0.8.9;

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

/**
 * @dev Context variant with ERC2771 support.
 */
abstract contract ERC2771Context is Context {
    /// @custom:oz-upgrades-unsafe-allow state-variable-immutable
    address private immutable _trustedForwarder;

    /// @custom:oz-upgrades-unsafe-allow constructor
    constructor(address trustedForwarder) {
        _trustedForwarder = trustedForwarder;
    }

    function isTrustedForwarder(address forwarder) public view virtual returns (bool) {
        return forwarder == _trustedForwarder;
    }

    function _msgSender() internal view virtual override returns (address sender) {
        if (isTrustedForwarder(msg.sender)) {
            // The assembly code is more direct than the Solidity version using `abi.decode`.
            /// @solidity memory-safe-assembly
            assembly {
                sender := shr(96, calldataload(sub(calldatasize(), 20)))
            }
        } else {
            return super._msgSender();
        }
    }

    function _msgData() internal view virtual override returns (bytes calldata) {
        if (isTrustedForwarder(msg.sender)) {
            return msg.data[:msg.data.length - 20];
        } else {
            return super._msgData();
        }
    }
}

// File: @openzeppelin/contracts/security/ReentrancyGuard.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (security/ReentrancyGuard.sol)

pragma solidity ^0.8.0;

/**
 * @dev Contract module that helps prevent reentrant calls to a function.
 *
 * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
 * available, which can be applied to functions to make sure there are no nested
 * (reentrant) calls to them.
 *
 * Note that because there is a single `nonReentrant` guard, functions marked as
 * `nonReentrant` may not call one another. This can be worked around by making
 * those functions `private`, and then adding `external` `nonReentrant` entry
 * points to them.
 *
 * TIP: If you would like to learn more about reentrancy and alternative ways
 * to protect against it, check out our blog post
 * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
 */
abstract contract ReentrancyGuard {
    // Booleans are more expensive than uint256 or any type that takes up a full
    // word because each write operation emits an extra SLOAD to first read the
    // slot's contents, replace the bits taken up by the boolean, and then write
    // back. This is the compiler's defense against contract upgrades and
    // pointer aliasing, and it cannot be disabled.

    // The values being non-zero value makes deployment a bit more expensive,
    // but in exchange the refund on every call to nonReentrant will be lower in
    // amount. Since refunds are capped to a percentage of the total
    // transaction's gas, it is best to keep them low in cases like this one, to
    // increase the likelihood of the full refund coming into effect.
    uint256 private constant _NOT_ENTERED = 1;
    uint256 private constant _ENTERED = 2;

    uint256 private _status;

    constructor() {
        _status = _NOT_ENTERED;
    }

    /**
     * @dev Prevents a contract from calling itself, directly or indirectly.
     * Calling a `nonReentrant` function from another `nonReentrant`
     * function is not supported. It is possible to prevent this from happening
     * by making the `nonReentrant` function external, and making it call a
     * `private` function that does the actual work.
     */
    modifier nonReentrant() {
        // On the first call to nonReentrant, _notEntered will be true
        require(_status != _ENTERED, "ReentrancyGuard: reentrant call");

        // Any calls to nonReentrant after this point will fail
        _status = _ENTERED;

        _;

        // By storing the original value once again, a refund is triggered (see
        // https://eips.ethereum.org/EIPS/eip-2200)
        _status = _NOT_ENTERED;
    }
}

// File: @openzeppelin/contracts/token/ERC20/extensions/draft-IERC20Permit.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/draft-IERC20Permit.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
 * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
 *
 * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
 * presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
 * need to send a transaction, and thus is not required to hold Ether at all.
 */
interface IERC20Permit {
    /**
     * @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,
     * given ``owner``'s signed approval.
     *
     * IMPORTANT: The same issues {IERC20-approve} has related to transaction
     * ordering also apply here.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `deadline` must be a timestamp in the future.
     * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
     * over the EIP712-formatted function arguments.
     * - the signature must use ``owner``'s current nonce (see {nonces}).
     *
     * For more information on the signature format, see the
     * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
     * section].
     */
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external;

    /**
     * @dev Returns the current nonce for `owner`. This value must be
     * included whenever a signature is generated for {permit}.
     *
     * Every successful call to {permit} increases ``owner``'s nonce by one. This
     * prevents a signature from being used multiple times.
     */
    function nonces(address owner) external view returns (uint256);

    /**
     * @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.
     */
    // solhint-disable-next-line func-name-mixedcase
    function DOMAIN_SEPARATOR() external view returns (bytes32);
}

// File: @openzeppelin/contracts/token/ERC20/extensions/IERC20Metadata.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol)

pragma solidity ^0.8.0;

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



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (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/token/ERC20/utils/SafeERC20.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (token/ERC20/utils/SafeERC20.sol)

pragma solidity ^0.8.0;

import "../IERC20.sol";
import "../extensions/draft-IERC20Permit.sol";
import "../../../utils/Address.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 SafeERC20 {
    using Address for address;

    function safeTransfer(
        IERC20 token,
        address to,
        uint256 value
    ) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }

    function safeTransferFrom(
        IERC20 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(
        IERC20 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(
        IERC20 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(
        IERC20 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));
        }
    }

    function safePermit(
        IERC20Permit token,
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) internal {
        uint256 nonceBefore = token.nonces(owner);
        token.permit(owner, spender, value, deadline, v, r, s);
        uint256 nonceAfter = token.nonces(owner);
        require(nonceAfter == nonceBefore + 1, "SafeERC20: permit did not succeed");
    }

    /**
     * @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(IERC20 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: @openzeppelin/contracts/utils/Address.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (utils/Address.sol)

pragma solidity ^0.8.1;

/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @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
     * ====
     *
     * [IMPORTANT]
     * ====
     * You shouldn't rely on `isContract` to protect against flash loan attacks!
     *
     * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
     * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
     * constructor.
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize/address.code.length, which returns 0
        // for contracts in construction, since the code is only stored at the end
        // of the constructor execution.

        return account.code.length > 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 Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(isContract(target), "Address: delegate call to non-contract");

        (bool success, bytes memory returndata) = target.delegatecall(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
                /// @solidity memory-safe-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

// 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/facade/Zapper.sol



// SPDX-License-Identifier: BlueOak-1.0.0
pragma solidity 0.8.17;
import { Address } from "@openzeppelin/contracts/utils/Address.sol";
import { SafeERC20 } from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import { ReentrancyGuard } from "@openzeppelin/contracts/security/ReentrancyGuard.sol";
import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";

import { ERC2771Context } from "@openzeppelin/contracts/metatx/ERC2771Context.sol";

import { IWrappedNative } from "../interfaces/IWrappedNative.sol";
import { Call, ZapERC20Params } from "../interfaces/IRTokenZapper.sol";
import { IPermit2, SignatureTransferDetails, PermitTransferFrom } from "../interfaces/IPermit2.sol";

contract ZapperExecutor {
    receive() external payable {}

    /** @dev Main endpoint to call
     * @param calls - Each call to execute
     */
    function execute(Call[] calldata calls) external {
        uint256 len = calls.length;
        for (uint256 i; i < len; i++) {
            if (calls[i].value == 0) {
                Address.functionCall(calls[i].to, calls[i].data);
            } else {
                Address.functionCallWithValue(calls[i].to, calls[i].data, calls[i].value);
            }
        }
    }

    /** @dev Utility for returning remaining funds back to user
     * @param tokens - Tokens to move out of the ZapperExecutor contract
     * @param destination - Recipient of the ERC20 transfers
     */
    function drainERC20s(IERC20[] calldata tokens, address destination) external {
        uint256 len = tokens.length;
        for (uint256 i; i < len; i++) {
            IERC20 token = tokens[i];
            uint256 balance = token.balanceOf(address(this));
            if (balance == 0) {
                continue;
            }
            SafeERC20.safeTransfer(token, destination, balance);
        }
    }

    /** @dev Utility for setting up all neccesary approvals for Zap
     * @param tokens - Tokens to set up approvals
     * @param spenders - Spenders - i'th token will be approved for i'th spender
     */
    function setupApprovals(IERC20[] calldata tokens, address[] calldata spenders) external {
        require(tokens.length == spenders.length, "Invalid params");
        uint256 len = tokens.length;
        for (uint256 i; i < len; i++) {
            IERC20 token = tokens[i];
            address spender = spenders[i];

            uint256 allowance = token.allowance(address(this), spender);

            if (allowance != 0) {
                continue;
            }
            SafeERC20.safeApprove(token, spender, type(uint256).max);
        }
    }

    /** Callbacks added to allow the executor to directly trade with uniswapv3-like pools */
    function algebraSwapCallback(
        int256,
        int256,
        bytes calldata data
    ) external {
        this.execute(abi.decode(data, (Call[])));
    }

    function uniswapV3SwapCallback(
        int256,
        int256,
        bytes calldata data
    ) external {
        this.execute(abi.decode(data, (Call[])));
    }

    function swapCallback(
        int256,
        int256,
        bytes calldata data
    ) external {
        this.execute(abi.decode(data, (Call[])));
    }
}

contract Zapper is ReentrancyGuard {
    IWrappedNative internal immutable wrappedNative;
    IPermit2 internal immutable permit2;
    ZapperExecutor internal immutable zapperExecutor;

    constructor(
        IWrappedNative wrappedNative_,
        IPermit2 permit2_,
        ZapperExecutor executor_
    ) {
        wrappedNative = wrappedNative_;
        permit2 = permit2_;
        zapperExecutor = executor_;
    }

    function zapERC20_(ZapERC20Params calldata params) internal {
        uint256 initialBalance = params.tokenOut.balanceOf(msg.sender);
        // STEP 1: Execute
        zapperExecutor.execute(params.commands);

        // STEP 2: Verify that the user has gotten the tokens they requested
        uint256 newBalance = params.tokenOut.balanceOf(msg.sender);
        require(newBalance > initialBalance, "INVALID_NEW_BALANCE");
        uint256 difference = newBalance - initialBalance;
        require(difference >= params.amountOut, "INSUFFICIENT_OUT");
    }

    receive() external payable {
        require(msg.sender == address(wrappedNative), "INVALID_CALLER");
    }

    function zapERC20(ZapERC20Params calldata params) external nonReentrant {
        require(params.amountIn != 0, "INVALID_INPUT_AMOUNT");
        require(params.amountOut != 0, "INVALID_OUTPUT_AMOUNT");
        SafeERC20.safeTransferFrom(
            params.tokenIn,
            msg.sender,
            address(zapperExecutor),
            params.amountIn
        );
        zapERC20_(params);
    }

    function zapERC20WithPermit2(
        ZapERC20Params calldata params,
        PermitTransferFrom calldata permit,
        bytes calldata signature
    ) external nonReentrant {
        require(params.amountIn != 0, "INVALID_INPUT_AMOUNT");
        require(params.amountOut != 0, "INVALID_OUTPUT_AMOUNT");

        permit2.permitTransferFrom(
            permit,
            SignatureTransferDetails({
                to: address(zapperExecutor),
                requestedAmount: params.amountIn
            }),
            msg.sender,
            signature
        );

        zapERC20_(params);
    }

    function zapETH(ZapERC20Params calldata params) external payable nonReentrant {
        require(address(params.tokenIn) == address(wrappedNative), "INVALID_INPUT_TOKEN");
        require(params.amountIn == msg.value, "INVALID_INPUT_AMOUNT");
        require(msg.value != 0, "INVALID_INPUT_AMOUNT");
        require(params.amountOut != 0, "INVALID_OUTPUT_AMOUNT");
        wrappedNative.deposit{ value: msg.value }();
        SafeERC20.safeTransfer(
            wrappedNative,
            address(zapperExecutor),
            wrappedNative.balanceOf(address(this))
        );
        zapERC20_(params);
    }
}

// File: contracts/interfaces/IAsset.sol



// SPDX-License-Identifier: BlueOak-1.0.0
pragma solidity 0.8.17;

import "@chainlink/contracts/src/v0.8/interfaces/AggregatorV3Interface.sol";
import "@openzeppelin/contracts/token/ERC20/extensions/IERC20Metadata.sol";
import "../libraries/Fixed.sol";
import "./IMain.sol";
import "./IRewardable.sol";

/**
 * @title IAsset
 * @notice Supertype. Any token that interacts with our system must be wrapped in an asset,
 * whether it is used as RToken backing or not. Any token that can report a price in the UoA
 * is eligible to be an asset.
 */
interface IAsset is IRewardable {
    /// Refresh saved price
    /// The Reserve protocol calls this at least once per transaction, before relying on
    /// the Asset's other functions.
    /// @dev Called immediately after deployment, before use
    function refresh() external;

    /// Should not revert
    /// @return low {UoA/tok} The lower end of the price estimate
    /// @return high {UoA/tok} The upper end of the price estimate
    function price() external view returns (uint192 low, uint192 high);

    /// Should not revert
    /// lotLow should be nonzero when the asset might be worth selling
    /// @return lotLow {UoA/tok} The lower end of the lot price estimate
    /// @return lotHigh {UoA/tok} The upper end of the lot price estimate
    function lotPrice() external view returns (uint192 lotLow, uint192 lotHigh);

    /// @return {tok} The balance of the ERC20 in whole tokens
    function bal(address account) external view returns (uint192);

    /// @return The ERC20 contract of the token with decimals() available
    function erc20() external view returns (IERC20Metadata);

    /// @return The number of decimals in the ERC20; just for gas optimization
    function erc20Decimals() external view returns (uint8);

    /// @return If the asset is an instance of ICollateral or not
    function isCollateral() external view returns (bool);

    /// @param {UoA} The max trade volume, in UoA
    function maxTradeVolume() external view returns (uint192);
}

// Used only in Testing. Strictly speaking an Asset does not need to adhere to this interface
interface TestIAsset is IAsset {
    /// @return The address of the chainlink feed
    function chainlinkFeed() external view returns (AggregatorV3Interface);

    /// {1} The max % deviation allowed by the oracle
    function oracleError() external view returns (uint192);

    /// @return {s} Seconds that an oracle value is considered valid
    function oracleTimeout() external view returns (uint48);

    /// @return {s} Seconds that the lotPrice should decay over, after stale price
    function priceTimeout() external view returns (uint48);
}

/// CollateralStatus must obey a linear ordering. That is:
/// - being DISABLED is worse than being IFFY, or SOUND
/// - being IFFY is worse than being SOUND.
enum CollateralStatus {
    SOUND,
    IFFY, // When a peg is not holding or a chainlink feed is stale
    DISABLED // When the collateral has completely defaulted
}

/// Upgrade-safe maximum operator for CollateralStatus
library CollateralStatusComparator {
    /// @return Whether a is worse than b
    function worseThan(CollateralStatus a, CollateralStatus b) internal pure returns (bool) {
        return uint256(a) > uint256(b);
    }
}

/**
 * @title ICollateral
 * @notice A subtype of Asset that consists of the tokens eligible to back the RToken.
 */
interface ICollateral is IAsset {
    /// Emitted whenever the collateral status is changed
    /// @param newStatus The old CollateralStatus
    /// @param newStatus The updated CollateralStatus
    event CollateralStatusChanged(
        CollateralStatus indexed oldStatus,
        CollateralStatus indexed newStatus
    );

    /// @dev refresh()
    /// Refresh exchange rates and update default status.
    /// VERY IMPORTANT: In any valid implemntation, status() MUST become DISABLED in refresh() if
    /// refPerTok() has ever decreased since last call.

    /// @return The canonical name of this collateral's target unit.
    function targetName() external view returns (bytes32);

    /// @return The status of this collateral asset. (Is it defaulting? Might it soon?)
    function status() external view returns (CollateralStatus);

    // ==== Exchange Rates ====

    /// @return {ref/tok} Quantity of whole reference units per whole collateral tokens
    function refPerTok() external view returns (uint192);

    /// @return {target/ref} Quantity of whole target units per whole reference unit in the peg
    function targetPerRef() external view returns (uint192);
}

// Used only in Testing. Strictly speaking a Collateral does not need to adhere to this interface
interface TestICollateral is TestIAsset, ICollateral {
    /// @return The epoch timestamp when the collateral will default from IFFY to DISABLED
    function whenDefault() external view returns (uint256);

    /// @return The amount of time a collateral must be in IFFY status until being DISABLED
    function delayUntilDefault() external view returns (uint48);
}

// File: contracts/interfaces/IAssetRegistry.sol



// SPDX-License-Identifier: BlueOak-1.0.0
pragma solidity 0.8.17;

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

/// A serialization of the AssetRegistry to be passed around in the P1 impl for gas optimization
struct Registry {
    IERC20[] erc20s;
    IAsset[] assets;
}

/**
 * @title IAssetRegistry
 * @notice The AssetRegistry is in charge of maintaining the ERC20 tokens eligible
 *   to be handled by the rest of the system. If an asset is in the registry, this means:
 *      1. Its ERC20 contract has been vetted
 *      2. The asset is the only asset for that ERC20
 *      3. The asset can be priced in the UoA, usually via an oracle
 */
interface IAssetRegistry is IComponent {
    /// Emitted when an asset is added to the registry
    /// @param erc20 The ERC20 contract for the asset
    /// @param asset The asset contract added to the registry
    event AssetRegistered(IERC20 indexed erc20, IAsset indexed asset);

    /// Emitted when an asset is removed from the registry
    /// @param erc20 The ERC20 contract for the asset
    /// @param asset The asset contract removed from the registry
    event AssetUnregistered(IERC20 indexed erc20, IAsset indexed asset);

    // Initialization
    function init(IMain main_, IAsset[] memory assets_) external;

    /// Fully refresh all asset state
    /// @custom:interaction
    function refresh() external;

    /// @return The corresponding asset for ERC20, or reverts if not registered
    function toAsset(IERC20 erc20) external view returns (IAsset);

    /// @return The corresponding collateral, or reverts if unregistered or not collateral
    function toColl(IERC20 erc20) external view returns (ICollateral);

    /// @return If the ERC20 is registered
    function isRegistered(IERC20 erc20) external view returns (bool);

    /// @return A list of all registered ERC20s
    function erc20s() external view returns (IERC20[] memory);

    /// @return reg The list of registered ERC20s and Assets, in the same order
    function getRegistry() external view returns (Registry memory reg);

    function register(IAsset asset) external returns (bool);

    function swapRegistered(IAsset asset) external returns (bool swapped);

    function unregister(IAsset asset) external;
}

// File: contracts/interfaces/IBackingManager.sol



// SPDX-License-Identifier: BlueOak-1.0.0
pragma solidity 0.8.17;

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

/**
 * @title IBackingManager
 * @notice The BackingManager handles changes in the ERC20 balances that back an RToken.
 *   - It computes which trades to perform, if any, and initiates these trades with the Broker.
 *   - If already collateralized, excess assets are transferred to RevenueTraders.
 *
 * `manageTokens(erc20s)` and `manageTokensSortedOrder(erc20s)` are handles for getting at the
 *   same underlying functionality. The former allows an ERC20 list in any order, while the
 *   latter requires a sorted array, and executes in O(n) rather than O(n^2) time. In the
 *   vast majority of cases we expect the the O(n^2) function to be acceptable.
 */
interface IBackingManager is IComponent, ITrading {
    event TradingDelaySet(uint48 indexed oldVal, uint48 indexed newVal);
    event BackingBufferSet(uint192 indexed oldVal, uint192 indexed newVal);

    // Initialization
    function init(
        IMain main_,
        uint48 tradingDelay_,
        uint192 backingBuffer_,
        uint192 maxTradeSlippage_,
        uint192 minTradeVolume_
    ) external;

    // Give RToken max allowance over a registered token
    /// @custom:refresher
    /// @custom:interaction
    function grantRTokenAllowance(IERC20) external;

    /// Maintain the overall backing policy; handout assets otherwise
    /// @dev Performs a uniqueness check on the erc20s list in O(n^2)
    /// @custom:interaction
    function manageTokens(IERC20[] memory erc20s) external;

    /// Maintain the overall backing policy; handout assets otherwise
    /// @dev Tokens must be in sorted order!
    /// @dev Performs a uniqueness check on the erc20s list in O(n)
    /// @custom:interaction
    function manageTokensSortedOrder(IERC20[] memory erc20s) external;
}

interface TestIBackingManager is IBackingManager, TestITrading {
    function tradingDelay() external view returns (uint48);

    function backingBuffer() external view returns (uint192);

    function setTradingDelay(uint48 val) external;

    function setBackingBuffer(uint192 val) external;
}

// File: contracts/interfaces/IBasketHandler.sol



// SPDX-License-Identifier: BlueOak-1.0.0
pragma solidity 0.8.17;

import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "../libraries/Fixed.sol";
import "./IAsset.sol";
import "./IComponent.sol";

struct BasketRange {
    uint192 bottom; // {BU}
    uint192 top; // {BU}
}

/**
 * @title IBasketHandler
 * @notice The BasketHandler aims to maintain a reference basket of constant target unit amounts.
 * When a collateral token defaults, a new reference basket of equal target units is set.
 * When _all_ collateral tokens default for a target unit, only then is the basket allowed to fall
 *   in terms of target unit amounts. The basket is considered defaulted in this case.
 */
interface IBasketHandler is IComponent {
    /// Emitted when the prime basket is set
    /// @param erc20s The collateral tokens for the prime basket
    /// @param targetAmts {target/BU} A list of quantities of target unit per basket unit
    /// @param targetNames Each collateral token's targetName
    event PrimeBasketSet(IERC20[] erc20s, uint192[] targetAmts, bytes32[] targetNames);

    /// Emitted when the reference basket is set
    /// @param nonce The basket nonce
    /// @param erc20s The list of collateral tokens in the reference basket
    /// @param refAmts {ref/BU} The reference amounts of the basket collateral tokens
    /// @param disabled True when the list of erc20s + refAmts may not be correct
    event BasketSet(uint256 indexed nonce, IERC20[] erc20s, uint192[] refAmts, bool disabled);

    /// Emitted when a backup config is set for a target unit
    /// @param targetName The name of the target unit as a bytes32
    /// @param max The max number to use from `erc20s`
    /// @param erc20s The set of backup collateral tokens
    event BackupConfigSet(bytes32 indexed targetName, uint256 indexed max, IERC20[] erc20s);

    // Initialization
    function init(IMain main_) external;

    /// Set the prime basket
    /// @param erc20s The collateral tokens for the new prime basket
    /// @param targetAmts The target amounts (in) {target/BU} for the new prime basket
    ///                   required range: 1e9 values; absolute range irrelevant.
    /// @custom:governance
    function setPrimeBasket(IERC20[] memory erc20s, uint192[] memory targetAmts) external;

    /// Set the backup configuration for a given target
    /// @param targetName The name of the target as a bytes32
    /// @param max The maximum number of collateral tokens to use from this target
    ///            Required range: 1-255
    /// @param erc20s A list of ordered backup collateral tokens
    /// @custom:governance
    function setBackupConfig(
        bytes32 targetName,
        uint256 max,
        IERC20[] calldata erc20s
    ) external;

    /// Default the basket in order to schedule a basket refresh
    /// @custom:protected
    function disableBasket() external;

    /// Governance-controlled setter to cause a basket switch explicitly
    /// @custom:governance
    /// @custom:interaction
    function refreshBasket() external;

    /// @return If the BackingManager has sufficient collateral to redeem the entire RToken supply
    function fullyCollateralized() external view returns (bool);

    /// @return status The worst CollateralStatus of all collateral in the basket
    function status() external view returns (CollateralStatus status);

    /// @param erc20 The ERC20 token contract for the asset
    /// @return {tok/BU} The whole token quantity of token in the reference basket
    /// Returns 0 if erc20 is not registered or not in the basket
    /// Returns FIX_MAX (in lieu of +infinity) if Collateral.refPerTok() is 0.
    /// Otherwise, returns (token's basket.refAmts / token's Collateral.refPerTok())
    function quantity(IERC20 erc20) external view returns (uint192);

    /// Like quantity(), but unsafe because it DOES NOT CONFIRM THAT THE ASSET IS CORRECT
    /// @param erc20 The ERC20 token contract for the asset
    /// @param asset The registered asset plugin contract for the erc20
    /// @return {tok/BU} The whole token quantity of token in the reference basket
    /// Returns 0 if erc20 is not registered or not in the basket
    /// Returns FIX_MAX (in lieu of +infinity) if Collateral.refPerTok() is 0.
    /// Otherwise, returns (token's basket.refAmts / token's Collateral.refPerTok())
    function quantityUnsafe(IERC20 erc20, IAsset asset) external view returns (uint192);

    /// @param amount {BU}
    /// @return erc20s The addresses of the ERC20 tokens in the reference basket
    /// @return quantities {qTok} The quantity of each ERC20 token to issue `amount` baskets
    function quote(uint192 amount, RoundingMode rounding)
        external
        view
        returns (address[] memory erc20s, uint256[] memory quantities);

    /// @return top {BU} The number of partial basket units: e.g max(coll.map((c) => c.balAsBUs())
    ///         bottom {BU} The number of whole basket units held by the account
    function basketsHeldBy(address account) external view returns (BasketRange memory);

    /// Should not revert
    /// @return low {UoA/BU} The lower end of the price estimate
    /// @return high {UoA/BU} The upper end of the price estimate
    function price() external view returns (uint192 low, uint192 high);

    /// Should not revert
    /// lotLow should be nonzero if a BU could be worth selling
    /// @return lotLow {UoA/tok} The lower end of the lot price estimate
    /// @return lotHigh {UoA/tok} The upper end of the lot price estimate
    function lotPrice() external view returns (uint192 lotLow, uint192 lotHigh);

    /// @return timestamp The timestamp at which the basket was last set
    function timestamp() external view returns (uint48);

    /// @return The current basket nonce, regardless of status
    function nonce() external view returns (uint48);
}

// File: contracts/interfaces/IBroker.sol



// SPDX-License-Identifier: BlueOak-1.0.0
pragma solidity 0.8.17;

import "./IAsset.sol";
import "./IComponent.sol";
import "./IGnosis.sol";
import "./ITrade.sol";

/// The data format that describes a request for trade with the Broker
struct TradeRequest {
    IAsset sell;
    IAsset buy;
    uint256 sellAmount; // {qSellTok}
    uint256 minBuyAmount; // {qBuyTok}
}

/**
 * @title IBroker
 * @notice The Broker deploys oneshot Trade contracts for Traders and monitors
 *   the continued proper functioning of trading platforms.
 */
interface IBroker is IComponent {
    event GnosisSet(IGnosis indexed oldVal, IGnosis indexed newVal);
    event TradeImplementationSet(ITrade indexed oldVal, ITrade indexed newVal);
    event AuctionLengthSet(uint48 indexed oldVal, uint48 indexed newVal);
    event DisabledSet(bool indexed prevVal, bool indexed newVal);

    // Initialization
    function init(
        IMain main_,
        IGnosis gnosis_,
        ITrade tradeImplementation_,
        uint48 auctionLength_
    ) external;

    /// Request a trade from the broker
    /// @dev Requires setting an allowance in advance
    /// @custom:interaction
    function openTrade(TradeRequest memory req) external returns (ITrade);

    /// Only callable by one of the trading contracts the broker deploys
    function reportViolation() external;

    function disabled() external view returns (bool);
}

interface TestIBroker is IBroker {
    function gnosis() external view returns (IGnosis);

    function tradeImplementation() external view returns (ITrade);

    function auctionLength() external view returns (uint48);

    function setGnosis(IGnosis newGnosis) external;

    function setTradeImplementation(ITrade newTradeImplementation) external;

    function setAuctionLength(uint48 newAuctionLength) external;

    function setDisabled(bool disabled_) external;
}

// File: contracts/interfaces/IComponent.sol



// SPDX-License-Identifier: BlueOak-1.0.0
pragma solidity 0.8.17;

import "./IMain.sol";
import "./IVersioned.sol";

/**
 * @title IComponent
 * @notice A Component is the central building block of all our system contracts. Components
 *   contain important state that must be migrated during upgrades, and they delegate
 *   their ownership to Main's owner.
 */
interface IComponent is IVersioned {
    function main() external view returns (IMain);
}

// File: contracts/interfaces/IDistributor.sol



// SPDX-License-Identifier: BlueOak-1.0.0
pragma solidity 0.8.17;

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

struct RevenueShare {
    uint16 rTokenDist; // {revShare} A value between [0, 10,000]
    uint16 rsrDist; // {revShare} A value between [0, 10,000]
}

/// Assumes no more than 1024 independent distributions.
struct RevenueTotals {
    uint24 rTokenTotal; // {revShare}
    uint24 rsrTotal; // {revShare}
}

/**
 * @title IDistributor
 * @notice The Distributor Component maintains a revenue distribution table that dictates
 *   how to divide revenue across the Furnace, StRSR, and any other destinations.
 */
interface IDistributor is IComponent {
    /// Emitted when a distribution is set
    /// @param dest The address set to receive the distribution
    /// @param rTokenDist The distribution of RToken that should go to `dest`
    /// @param rsrDist The distribution of RSR that should go to `dest`
    event DistributionSet(address dest, uint16 rTokenDist, uint16 rsrDist);

    /// Emitted when revenue is distributed
    /// @param erc20 The token being distributed, either RSR or the RToken itself
    /// @param source The address providing the revenue
    /// @param amount The amount of the revenue
    event RevenueDistributed(IERC20 indexed erc20, address indexed source, uint256 indexed amount);

    // Initialization
    function init(IMain main_, RevenueShare memory dist) external;

    /// @custom:governance
    function setDistribution(address dest, RevenueShare memory share) external;

    /// Distribute the `erc20` token across all revenue destinations
    /// @custom:interaction
    function distribute(IERC20 erc20, uint256 amount) external;

    /// @return revTotals The total of all  destinations
    function totals() external view returns (RevenueTotals memory revTotals);
}

interface TestIDistributor is IDistributor {
    // solhint-disable-next-line func-name-mixedcase
    function FURNACE() external view returns (address);

    // solhint-disable-next-line func-name-mixedcase
    function ST_RSR() external view returns (address);

    /// @return rTokenDist The RToken distribution for the address
    /// @return rsrDist The RSR distribution for the address
    function distribution(address) external view returns (uint16 rTokenDist, uint16 rsrDist);
}

// File: contracts/interfaces/IFurnace.sol



// SPDX-License-Identifier: BlueOak-1.0.0
pragma solidity 0.8.17;

import "../libraries/Fixed.sol";
import "./IComponent.sol";

/**
 * @title IFurnace
 * @notice A helper contract to burn RTokens slowly and permisionlessly.
 */
interface IFurnace is IComponent {
    // Initialization
    function init(IMain main_, uint192 ratio_) external;

    /// Emitted when the melting ratio is changed
    /// @param oldRatio The old ratio
    /// @param newRatio The new ratio
    event RatioSet(uint192 indexed oldRatio, uint192 indexed newRatio);

    function ratio() external view returns (uint192);

    ///    Needed value range: [0, 1], granularity 1e-9
    /// @custom:governance
    function setRatio(uint192) external;

    /// Performs any RToken melting that has vested since the last payout.
    /// @custom:refresher
    function melt() external;
}

interface TestIFurnace is IFurnace {
    function lastPayout() external view returns (uint256);

    function lastPayoutBal() external view returns (uint256);
}

// File: contracts/interfaces/IGnosis.sol



// SPDX-License-Identifier: BlueOak-1.0.0
pragma solidity 0.8.17;

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

struct GnosisAuctionData {
    IERC20 auctioningToken;
    IERC20 biddingToken;
    uint256 orderCancellationEndDate;
    uint256 auctionEndDate;
    bytes32 initialAuctionOrder;
    uint256 minimumBiddingAmountPerOrder;
    uint256 interimSumBidAmount;
    bytes32 interimOrder;
    bytes32 clearingPriceOrder;
    uint96 volumeClearingPriceOrder;
    bool minFundingThresholdNotReached;
    bool isAtomicClosureAllowed;
    uint256 feeNumerator;
    uint256 minFundingThreshold;
}

/// The relevant portion of the interface of the live Gnosis EasyAuction contract
/// https://github.com/gnosis/ido-contracts/blob/main/contracts/EasyAuction.sol
interface IGnosis {
    function initiateAuction(
        IERC20 auctioningToken,
        IERC20 biddingToken,
        uint256 orderCancellationEndDate,
        uint256 auctionEndDate,
        uint96 auctionedSellAmount,
        uint96 minBuyAmount,
        uint256 minimumBiddingAmountPerOrder,
        uint256 minFundingThreshold,
        bool isAtomicClosureAllowed,
        address accessManagerContract,
        bytes memory accessManagerContractData
    ) external returns (uint256 auctionId);

    function auctionData(uint256 auctionId) external view returns (GnosisAuctionData memory);

    /// @param auctionId The external auction id
    /// @dev See here for decoding: https://git.io/JMang
    /// @return encodedOrder The order, encoded in a bytes 32
    function settleAuction(uint256 auctionId) external returns (bytes32 encodedOrder);

    /// @return The numerator over a 1000-valued denominator
    function feeNumerator() external returns (uint256);
}

// File: contracts/interfaces/IMain.sol



// SPDX-License-Identifier: BlueOak-1.0.0
pragma solidity 0.8.17;

import "@openzeppelin/contracts-upgradeable/access/IAccessControlUpgradeable.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "./IAssetRegistry.sol";
import "./IBasketHandler.sol";
import "./IBackingManager.sol";
import "./IBroker.sol";
import "./IGnosis.sol";
import "./IFurnace.sol";
import "./IDistributor.sol";
import "./IRToken.sol";
import "./IRevenueTrader.sol";
import "./IStRSR.sol";
import "./ITrading.sol";
import "./IVersioned.sol";

// === Auth roles ===

bytes32 constant OWNER = bytes32(bytes("OWNER"));
bytes32 constant SHORT_FREEZER = bytes32(bytes("SHORT_FREEZER"));
bytes32 constant LONG_FREEZER = bytes32(bytes("LONG_FREEZER"));
bytes32 constant PAUSER = bytes32(bytes("PAUSER"));

/**
 * Main is a central hub that maintains a list of Component contracts.
 *
 * Components:
 *   - perform a specific function
 *   - defer auth to Main
 *   - usually (but not always) contain sizeable state that require a proxy
 */
struct Components {
    // Definitely need proxy
    IRToken rToken;
    IStRSR stRSR;
    IAssetRegistry assetRegistry;
    IBasketHandler basketHandler;
    IBackingManager backingManager;
    IDistributor distributor;
    IFurnace furnace;
    IBroker broker;
    IRevenueTrader rsrTrader;
    IRevenueTrader rTokenTrader;
}

interface IAuth is IAccessControlUpgradeable {
    /// Emitted when `unfreezeAt` is changed
    /// @param oldVal The old value of `unfreezeAt`
    /// @param newVal The new value of `unfreezeAt`
    event UnfreezeAtSet(uint48 indexed oldVal, uint48 indexed newVal);

    /// Emitted when the short freeze duration governance param is changed
    /// @param oldDuration The old short freeze duration
    /// @param newDuration The new short freeze duration
    event ShortFreezeDurationSet(uint48 indexed oldDuration, uint48 indexed newDuration);

    /// Emitted when the long freeze duration governance param is changed
    /// @param oldDuration The old long freeze duration
    /// @param newDuration The new long freeze duration
    event LongFreezeDurationSet(uint48 indexed oldDuration, uint48 indexed newDuration);

    /// Emitted when the system is paused or unpaused
    /// @param oldVal The old value of `paused`
    /// @param newVal The new value of `paused`
    event PausedSet(bool indexed oldVal, bool indexed newVal);

    /**
     * Paused: Disable everything except for OWNER actions, RToken.redeem, StRSR.stake,
     * and StRSR.payoutRewards
     * Frozen: Disable everything except for OWNER actions + StRSR.stake (for governance)
     */

    function pausedOrFrozen() external view returns (bool);

    function frozen() external view returns (bool);

    function shortFreeze() external view returns (uint48);

    function longFreeze() external view returns (uint48);

    // ====

    // onlyRole(OWNER)
    function freezeForever() external;

    // onlyRole(SHORT_FREEZER)
    function freezeShort() external;

    // onlyRole(LONG_FREEZER)
    function freezeLong() external;

    // onlyRole(OWNER)
    function unfreeze() external;

    function pause() external;

    function unpause() external;
}

interface IComponentRegistry {
    // === Component setters/getters ===

    event RTokenSet(IRToken indexed oldVal, IRToken indexed newVal);

    function rToken() external view returns (IRToken);

    event StRSRSet(IStRSR indexed oldVal, IStRSR indexed newVal);

    function stRSR() external view returns (IStRSR);

    event AssetRegistrySet(IAssetRegistry indexed oldVal, IAssetRegistry indexed newVal);

    function assetRegistry() external view returns (IAssetRegistry);

    event BasketHandlerSet(IBasketHandler indexed oldVal, IBasketHandler indexed newVal);

    function basketHandler() external view returns (IBasketHandler);

    event BackingManagerSet(IBackingManager indexed oldVal, IBackingManager indexed newVal);

    function backingManager() external view returns (IBackingManager);

    event DistributorSet(IDistributor indexed oldVal, IDistributor indexed newVal);

    function distributor() external view returns (IDistributor);

    event RSRTraderSet(IRevenueTrader indexed oldVal, IRevenueTrader indexed newVal);

    function rsrTrader() external view returns (IRevenueTrader);

    event RTokenTraderSet(IRevenueTrader indexed oldVal, IRevenueTrader indexed newVal);

    function rTokenTrader() external view returns (IRevenueTrader);

    event FurnaceSet(IFurnace indexed oldVal, IFurnace indexed newVal);

    function furnace() external view returns (IFurnace);

    event BrokerSet(IBroker indexed oldVal, IBroker indexed newVal);

    function broker() external view returns (IBroker);
}

/**
 * @title IMain
 * @notice The central hub for the entire system. Maintains components and an owner singleton role
 */
interface IMain is IVersioned, IAuth, IComponentRegistry {
    function poke() external; // not used in p1

    // === Initialization ===

    event MainInitialized();

    function init(
        Components memory components,
        IERC20 rsr_,
        uint48 shortFreeze_,
        uint48 longFreeze_
    ) external;

    function rsr() external view returns (IERC20);
}

interface TestIMain is IMain {
    /// @custom:governance
    function setShortFreeze(uint48) external;

    /// @custom:governance
    function setLongFreeze(uint48) external;

    function shortFreeze() external view returns (uint48);

    function longFreeze() external view returns (uint48);

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

    function paused() external view returns (bool);
}

// File: contracts/interfaces/IPermit2.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.17;
/// @notice The token and amount details for a transfer signed in the permit transfer signature
struct TokenPermissions {
    // ERC20 token address
    address token;
    // the maximum amount that can be spent
    uint256 amount;
}

/// @notice The signed permit message for a single token transfer
struct PermitTransferFrom {
    TokenPermissions permitted;
    // a unique value for every token owner's signature to prevent signature replays
    uint256 nonce;
    // deadline on the permit signature
    uint256 deadline;
}

/// @notice Specifies the recipient address and amount for batched transfers.
/// @dev Recipients and amounts correspond to the index of the signed token permissions array.
/// @dev Reverts if the requested amount is greater than the permitted signed amount.
struct SignatureTransferDetails {
    // recipient address
    address to;
    // spender requested amount
    uint256 requestedAmount;
}

interface IPermit2 {
    /// @notice Transfers a token using a signed permit message
    /// @dev Reverts if the requested amount is greater than the permitted signed amount
    /// @param permit The permit data signed over by the owner
    /// @param owner The owner of the tokens to transfer
    /// @param transferDetails The spender's requested transfer details for the permitted token
    /// @param signature The signature to verify
    function permitTransferFrom(
        PermitTransferFrom memory permit,
        SignatureTransferDetails calldata transferDetails,
        address owner,
        bytes calldata signature
    ) external;
}

// File: contracts/interfaces/IRevenueTrader.sol



// SPDX-License-Identifier: BlueOak-1.0.0
pragma solidity 0.8.17;

import "./IComponent.sol";
import "./ITrading.sol";

/**
 * @title IRevenueTrader
 * @notice The RevenueTrader is an extension of the trading mixin that trades all
 *   assets at its address for a single target asset. There are two runtime instances
 *   of the RevenueTrader, 1 for RToken and 1 for RSR.
 */
interface IRevenueTrader is IComponent, ITrading {
    // Initialization
    function init(
        IMain main_,
        IERC20 tokenToBuy_,
        uint192 maxTradeSlippage_,
        uint192 minTradeVolume_
    ) external;

    /// Processes a single token; unpermissioned
    /// @dev Intended to be used with multicall
    /// @custom:interaction
    function manageToken(IERC20 sell) external;
}

// solhint-disable-next-line no-empty-blocks
interface TestIRevenueTrader is IRevenueTrader, TestITrading {
    function tokenToBuy() external view returns (IERC20);
}

// File: contracts/interfaces/IRewardable.sol



// SPDX-License-Identifier: BlueOak-1.0.0
pragma solidity 0.8.17;

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

/**
 * @title IRewardable
 * @notice A simple interface mixin to support claiming of rewards.
 */
interface IRewardable {
    /// Emitted whenever a reward token balance is claimed
    event RewardsClaimed(IERC20 indexed erc20, uint256 indexed amount);

    /// Claim rewards earned by holding a balance of the ERC20 token
    /// Must emit `RewardsClaimed` for each token rewards are claimed for
    /// @dev delegatecall: there be dragons here!
    /// @custom:interaction
    function claimRewards() external;
}

/**
 * @title IRewardableComponent
 * @notice A simple interface mixin to support claiming of rewards.
 */
interface IRewardableComponent is IRewardable {
    /// Claim rewards for a single ERC20
    /// Must emit `RewardsClaimed` for each token rewards are claimed for
    /// @dev delegatecall: there be dragons here!
    /// @custom:interaction
    function claimRewardsSingle(IERC20 erc20) external;
}

// File: contracts/interfaces/IRToken.sol



// SPDX-License-Identifier: BlueOak-1.0.0
pragma solidity 0.8.17;

import "@openzeppelin/contracts-upgradeable/token/ERC20/extensions/IERC20MetadataUpgradeable.sol";
// solhint-disable-next-line max-line-length
import "@openzeppelin/contracts-upgradeable/token/ERC20/extensions/draft-IERC20PermitUpgradeable.sol";
import "../libraries/Fixed.sol";
import "../libraries/Throttle.sol";
import "./IAsset.sol";
import "./IComponent.sol";
import "./IMain.sol";
import "./IRewardable.sol";

/**
 * @title IRToken
 * @notice An RToken is an ERC20 that is permissionlessly issuable/redeemable and tracks an
 *   exchange rate against a single unit: baskets, or {BU} in our type notation.
 */
interface IRToken is IComponent, IERC20MetadataUpgradeable, IERC20PermitUpgradeable {
    /// Emitted when an issuance of RToken occurs, whether it occurs via slow minting or not
    /// @param issuer The address holding collateral tokens
    /// @param recipient The address of the recipient of the RTokens
    /// @param amount The quantity of RToken being issued
    /// @param baskets The corresponding number of baskets
    event Issuance(
        address indexed issuer,
        address indexed recipient,
        uint256 indexed amount,
        uint192 baskets
    );

    /// Emitted when a redemption of RToken occurs
    /// @param redeemer The address holding RToken
    /// @param recipient The address of the account receiving the backing collateral tokens
    /// @param amount The quantity of RToken being redeemed
    /// @param baskets The corresponding number of baskets
    /// @param amount {qRTok} The amount of RTokens canceled
    event Redemption(
        address indexed redeemer,
        address indexed recipient,
        uint256 indexed amount,
        uint192 baskets
    );

    /// Emitted when the number of baskets needed changes
    /// @param oldBasketsNeeded Previous number of baskets units needed
    /// @param newBasketsNeeded New number of basket units needed
    event BasketsNeededChanged(uint192 oldBasketsNeeded, uint192 newBasketsNeeded);

    /// Emitted when RToken is melted, i.e the RToken supply is decreased but basketsNeeded is not
    /// @param amount {qRTok}
    event Melted(uint256 amount);

    /// Emitted when issuance SupplyThrottle params are set
    event IssuanceThrottleSet(ThrottleLib.Params oldVal, ThrottleLib.Params newVal);

    /// Emitted when redemption SupplyThrottle params are set
    event RedemptionThrottleSet(ThrottleLib.Params oldVal, ThrottleLib.Params newVal);

    // Initialization
    function init(
        IMain main_,
        string memory name_,
        string memory symbol_,
        string memory mandate_,
        ThrottleLib.Params calldata issuanceThrottleParams,
        ThrottleLib.Params calldata redemptionThrottleParams
    ) external;

    /// Issue an RToken with basket collateral
    /// @param amount {qRTok} The quantity of RToken to issue
    /// @custom:interaction
    function issue(uint256 amount) external;

    /// Issue an RToken with basket collateral, to a particular recipient
    /// @param recipient The address to receive the issued RTokens
    /// @param amount {qRTok} The quantity of RToken to issue
    /// @custom:interaction
    function issueTo(address recipient, uint256 amount) external;

    /// Redeem RToken for basket collateral
    /// @param amount {qRTok} The quantity {qRToken} of RToken to redeem
    /// @param basketNonce The nonce of the basket the redemption should be from; else reverts
    /// @custom:interaction
    function redeem(uint256 amount, uint48 basketNonce) external;

    /// Redeem RToken for basket collateral to a particular recipient
    /// @param recipient The address to receive the backing collateral tokens
    /// @param amount {qRTok} The quantity {qRToken} of RToken to redeem
    /// @param basketNonce The nonce of the basket the redemption should be from; else reverts
    /// @custom:interaction
    function redeemTo(
        address recipient,
        uint256 amount,
        uint48 basketNonce
    ) external;

    /// Mints a quantity of RToken to the `recipient`, callable only by the BackingManager
    /// @param recipient The recipient of the newly minted RToken
    /// @param amount {qRTok} The amount to be minted
    /// @custom:protected
    function mint(address recipient, uint256 amount) external;

    /// Melt a quantity of RToken from the caller's account
    /// @param amount {qRTok} The amount to be melted
    function melt(uint256 amount) external;

    /// Set the number of baskets needed directly, callable only by the BackingManager
    /// @param basketsNeeded {BU} The number of baskets to target
    ///                      needed range: pretty interesting
    /// @custom:protected
    function setBasketsNeeded(uint192 basketsNeeded) external;

    /// @return {BU} How many baskets are being targeted
    function basketsNeeded() external view returns (uint192);

    /// @return {qRTok} The maximum issuance that can be performed in the current block
    function issuanceAvailable() external view returns (uint256);

    /// @return {qRTok} The maximum redemption that can be performed in the current block
    function redemptionAvailable() external view returns (uint256);
}

interface TestIRToken is IRToken {
    function setIssuanceThrottleParams(ThrottleLib.Params calldata) external;

    function setRedemptionThrottleParams(ThrottleLib.Params calldata) external;

    function issuanceThrottleParams() external view returns (ThrottleLib.Params memory);

    function redemptionThrottleParams() external view returns (ThrottleLib.Params memory);

    function increaseAllowance(address, uint256) external returns (bool);

    function decreaseAllowance(address, uint256) external returns (bool);

    function monetizeDonations(IERC20) external;
}

// File: contracts/interfaces/IRTokenZapper.sol



// SPDX-License-Identifier: BlueOak-1.0.0
pragma solidity 0.8.17;

import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import { IRToken } from "../interfaces/IRToken.sol";

struct Call {
    address to;
    bytes data;
    uint256 value;
}

struct ZapERC20Params {
    // Token to zap
    IERC20 tokenIn;
    // Total amount to zap / pull from user
    uint256 amountIn;
    // Smart contract calls to execute to produce 'amountOut' of 'tokenOut'
    Call[] commands;
    // RTokens the user requested
    uint256 amountOut;
    // RToken to issue
    IRToken tokenOut;
}

// File: contracts/interfaces/IStRSR.sol



// SPDX-License-Identifier: BlueOak-1.0.0
pragma solidity 0.8.17;

import "@openzeppelin/contracts-upgradeable/token/ERC20/extensions/IERC20MetadataUpgradeable.sol";
// solhint-disable-next-line max-line-length
import "@openzeppelin/contracts-upgradeable/token/ERC20/extensions/draft-IERC20PermitUpgradeable.sol";
import "../libraries/Fixed.sol";
import "./IComponent.sol";
import "./IMain.sol";

/**
 * @title IStRSR
 * @notice An ERC20 token representing shares of the RSR over-collateralization pool.
 *
 * StRSR permits the BackingManager to take RSR in times of need. In return, the BackingManager
 * benefits the StRSR pool with RSR rewards purchased with a portion of its revenue.
 *
 * In the absence of collateral default or losses due to slippage, StRSR should have a
 * monotonically increasing exchange rate with respect to RSR, meaning that over time
 * StRSR is redeemable for more RSR. It is non-rebasing.
 */
interface IStRSR is IERC20MetadataUpgradeable, IERC20PermitUpgradeable, IComponent {
    /// Emitted when RSR is staked
    /// @param era The era at time of staking
    /// @param staker The address of the staker
    /// @param rsrAmount {qRSR} How much RSR was staked
    /// @param stRSRAmount {qStRSR} How much stRSR was minted by this staking
    event Staked(
        uint256 indexed era,
        address indexed staker,
        uint256 rsrAmount,
        uint256 indexed stRSRAmount
    );

    /// Emitted when an unstaking is started
    /// @param draftId The id of the draft.
    /// @param draftEra The era of the draft.
    /// @param staker The address of the unstaker
    ///   The triple (staker, draftEra, draftId) is a unique ID
    /// @param rsrAmount {qRSR} How much RSR this unstaking will be worth, absent seizures
    /// @param stRSRAmount {qStRSR} How much stRSR was burned by this unstaking
    event UnstakingStarted(
        uint256 indexed draftId,
        uint256 indexed draftEra,
        address indexed staker,
        uint256 rsrAmount,
        uint256 stRSRAmount,
        uint256 availableAt
    );

    /// Emitted when RSR is unstaked
    /// @param firstId The beginning of the range of draft IDs withdrawn in this transaction
    /// @param endId The end of range of draft IDs withdrawn in this transaction
    ///   (ID i was withdrawn if firstId <= i < endId)
    /// @param draftEra The era of the draft.
    ///   The triple (staker, draftEra, id) is a unique ID among drafts
    /// @param staker The address of the unstaker

    /// @param rsrAmount {qRSR} How much RSR this unstaking was worth
    event UnstakingCompleted(
        uint256 indexed firstId,
        uint256 indexed endId,
        uint256 draftEra,
        address indexed staker,
        uint256 rsrAmount
    );

    /// Emitted whenever the exchange rate changes
    event ExchangeRateSet(uint192 indexed oldVal, uint192 indexed newVal);

    /// Emitted whenever RSR are paids out
    event RewardsPaid(uint256 indexed rsrAmt);

    /// Emitted if all the RSR in the staking pool is seized and all balances are reset to zero.
    event AllBalancesReset(uint256 indexed newEra);
    /// Emitted if all the RSR in the unstakin pool is seized, and all ongoing unstaking is voided.
    event AllUnstakingReset(uint256 indexed newEra);

    event UnstakingDelaySet(uint48 indexed oldVal, uint48 indexed newVal);
    event RewardRatioSet(uint192 indexed oldVal, uint192 indexed newVal);

    // Initialization
    function init(
        IMain main_,
        string memory name_,
        string memory symbol_,
        uint48 unstakingDelay_,
        uint192 rewardRatio_
    ) external;

    /// Gather and payout rewards from rsrTrader
    /// @custom:interaction
    function payoutRewards() external;

    /// Stakes an RSR `amount` on the corresponding RToken to earn yield and over-collateralized
    /// the system
    /// @param amount {qRSR}
    /// @custom:interaction
    function stake(uint256 amount) external;

    /// Begins a delayed unstaking for `amount` stRSR
    /// @param amount {qStRSR}
    /// @custom:interaction
    function unstake(uint256 amount) external;

    /// Complete delayed unstaking for the account, up to (but not including!) `endId`
    /// @custom:interaction
    function withdraw(address account, uint256 endId) external;

    /// Seize RSR, only callable by main.backingManager()
    /// @custom:protected
    function seizeRSR(uint256 amount) external;

    /// Return the maximum valid value of endId such that withdraw(endId) should immediately work
    function endIdForWithdraw(address account) external view returns (uint256 endId);

    /// @return {qRSR/qStRSR} The exchange rate between RSR and StRSR
    function exchangeRate() external view returns (uint192);
}

interface TestIStRSR is IStRSR {
    function rewardRatio() external view returns (uint192);

    function setRewardRatio(uint192) external;

    function unstakingDelay() external view returns (uint48);

    function setUnstakingDelay(uint48) external;

    function increaseAllowance(address, uint256) external returns (bool);

    function decreaseAllowance(address, uint256) external returns (bool);

    /// @return {qStRSR/qRSR} The exchange rate between StRSR and RSR
    function exchangeRate() external view returns (uint192);
}

// File: contracts/interfaces/ITrade.sol



// SPDX-License-Identifier: BlueOak-1.0.0
pragma solidity 0.8.17;

import "@openzeppelin/contracts/token/ERC20/extensions/IERC20Metadata.sol";

/**
 * Simple generalized trading interface for all Trade contracts to obey
 *
 * Usage: if (canSettle()) settle()
 */
interface ITrade {
    function sell() external view returns (IERC20Metadata);

    function buy() external view returns (IERC20Metadata);

    /// @return The timestamp at which the trade is projected to become settle-able
    function endTime() external view returns (uint48);

    /// @return True if the trade can be settled
    /// @dev Should be guaranteed to be true eventually as an invariant
    function canSettle() external view returns (bool);

    /// Complete the trade and transfer tokens back to the origin trader
    /// @return soldAmt {qSellTok} The quantity of tokens sold
    /// @return boughtAmt {qBuyTok} The quantity of tokens bought
    function settle() external returns (uint256 soldAmt, uint256 boughtAmt);
}

// File: contracts/interfaces/ITrading.sol



// SPDX-License-Identifier: BlueOak-1.0.0
pragma solidity 0.8.17;

import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "../libraries/Fixed.sol";
import "./IAsset.sol";
import "./IComponent.sol";
import "./ITrade.sol";
import "./IRewardable.sol";

/**
 * @title ITrading
 * @notice Common events and refresher function for all Trading contracts
 */
interface ITrading is IComponent, IRewardableComponent {
    event MaxTradeSlippageSet(uint192 indexed oldVal, uint192 indexed newVal);
    event MinTradeVolumeSet(uint192 indexed oldVal, uint192 indexed newVal);

    /// Emitted when a trade is started
    /// @param trade The one-time-use trade contract that was just deployed
    /// @param sell The token to sell
    /// @param buy The token to buy
    /// @param sellAmount {qSellTok} The quantity of the selling token
    /// @param minBuyAmount {qBuyTok} The minimum quantity of the buying token to accept
    event TradeStarted(
        ITrade indexed trade,
        IERC20 indexed sell,
        IERC20 indexed buy,
        uint256 sellAmount,
        uint256 minBuyAmount
    );

    /// Emitted after a trade ends
    /// @param trade The one-time-use trade contract
    /// @param sell The token to sell
    /// @param buy The token to buy
    /// @param sellAmount {qSellTok} The quantity of the token sold
    /// @param buyAmount {qBuyTok} The quantity of the token bought
    event TradeSettled(
        ITrade indexed trade,
        IERC20 indexed sell,
        IERC20 indexed buy,
        uint256 sellAmount,
        uint256 buyAmount
    );

    /// Settle a single trade, expected to be used with multicall for efficient mass settlement
    /// @custom:refresher
    function settleTrade(IERC20 sell) external;

    /// @return {%} The maximum trade slippage acceptable
    function maxTradeSlippage() external view returns (uint192);

    /// @return {UoA} The minimum trade volume in UoA, applies to all assets
    function minTradeVolume() external view returns (uint192);

    /// @return The ongoing trade for a sell token, or the zero address
    function trades(IERC20 sell) external view returns (ITrade);

    /// @return The number of ongoing trades open
    function tradesOpen() external view returns (uint48);

    /// Light wrapper around FixLib.mulDiv to support try-catch
    function mulDivCeil(
        uint192 x,
        uint192 y,
        uint192 z
    ) external pure returns (uint192);
}

interface TestITrading is ITrading {
    /// @custom:governance
    function setMaxTradeSlippage(uint192 val) external;

    /// @custom:governance
    function setMinTradeVolume(uint192 val) external;
}

// File: contracts/interfaces/IVersioned.sol



// SPDX-License-Identifier: BlueOak-1.0.0
pragma solidity 0.8.17;

interface IVersioned {
    function version() external view returns (string memory);
}

// File: contracts/interfaces/IWrappedNative.sol



// SPDX-License-Identifier: BlueOak-1.0.0
pragma solidity 0.8.17;

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

interface IWrappedNative is IERC20 {
    function deposit() external payable;

    function withdraw(uint256) external;
}

// File: contracts/libraries/Fixed.sol



// SPDX-License-Identifier: BlueOak-1.0.0
// solhint-disable func-name-mixedcase func-visibility
pragma solidity ^0.8.17;

/// @title FixedPoint, a fixed-point arithmetic library defining the custom type uint192
/// @author Matt Elder <matt.elder@reserve.org> and the Reserve Team <https://reserve.org>

/** The logical type `uint192 ` is a 192 bit value, representing an 18-decimal Fixed-point
    fractional value.  This is what's described in the Solidity documentation as
    "fixed192x18" -- a value represented by 192 bits, that makes 18 digits available to
    the right of the decimal point.

    The range of values that uint192 can represent is about [-1.7e20, 1.7e20].
    Unless a function explicitly says otherwise, it will fail on overflow.
    To be clear, the following should hold:
    toFix(0) == 0
    toFix(1) == 1e18
*/

// Analysis notes:
//   Every function should revert iff its result is out of bounds.
//   Unless otherwise noted, when a rounding mode is given, that mode is applied to
//     a single division that may happen as the last step in the computation.
//   Unless otherwise noted, when a rounding mode is *not* given but is needed, it's FLOOR.
//   For each, we comment:
//   - @return is the value expressed  in "value space", where uint192(1e18) "is" 1.0
//   - as-ints: is the value expressed in "implementation space", where uint192(1e18) "is" 1e18
//   The "@return" expression is suitable for actually using the library
//   The "as-ints" expression is suitable for testing

// A uint value passed to this library was out of bounds for uint192 operations
error UIntOutOfBounds();
bytes32 constant UIntOutofBoundsHash = keccak256(abi.encodeWithSignature("UIntOutOfBounds()"));

// Used by P1 implementation for easier casting
uint256 constant FIX_ONE_256 = 1e18;
uint8 constant FIX_DECIMALS = 18;

// If a particular uint192 is represented by the uint192 n, then the uint192 represents the
// value n/FIX_SCALE.
uint64 constant FIX_SCALE = 1e18;

// FIX_SCALE Squared:
uint128 constant FIX_SCALE_SQ = 1e36;

// The largest integer that can be converted to uint192 .
// This is a bit bigger than 3.1e39
uint192 constant FIX_MAX_INT = type(uint192).max / FIX_SCALE;

uint192 constant FIX_ZERO = 0; // The uint192 representation of zero.
uint192 constant FIX_ONE = FIX_SCALE; // The uint192 representation of one.
uint192 constant FIX_MAX = type(uint192).max; // The largest uint192. (Not an integer!)
uint192 constant FIX_MIN = 0; // The smallest uint192.

/// An enum that describes a rounding approach for converting to ints
enum RoundingMode {
    FLOOR, // Round towards zero
    ROUND, // Round to the nearest int
    CEIL // Round away from zero
}

RoundingMode constant FLOOR = RoundingMode.FLOOR;
RoundingMode constant ROUND = RoundingMode.ROUND;
RoundingMode constant CEIL = RoundingMode.CEIL;

/* @dev Solidity 0.8.x only allows you to change one of type or size per type conversion.
   Thus, all the tedious-looking double conversions like uint256(uint256 (foo))
   See: https://docs.soliditylang.org/en/v0.8.17/080-breaking-changes.html#new-restrictions
 */

/// Explicitly convert a uint256 to a uint192. Revert if the input is out of bounds.
function _safeWrap(uint256 x) pure returns (uint192) {
    if (FIX_MAX < x) revert UIntOutOfBounds();
    return uint192(x);
}

/// Convert a uint to its Fix representation.
/// @return x
// as-ints: x * 1e18
function toFix(uint256 x) pure returns (uint192) {
    return _safeWrap(x * FIX_SCALE);
}

/// Convert a uint to its fixed-point representation, and left-shift its value `shiftLeft`
/// decimal digits.
/// @return x * 10**shiftLeft
// as-ints: x * 10**(shiftLeft + 18)
function shiftl_toFix(uint256 x, int8 shiftLeft) pure returns (uint192) {
    return shiftl_toFix(x, shiftLeft, FLOOR);
}

/// @return x * 10**shiftLeft
// as-ints: x * 10**(shiftLeft + 18)
function shiftl_toFix(
    uint256 x,
    int8 shiftLeft,
    RoundingMode rounding
) pure returns (uint192) {
    // conditions for avoiding overflow
    if (x == 0) return 0;
    if (shiftLeft <= -96) return (rounding == CEIL ? 1 : 0); // 0 < uint.max / 10**77 < 0.5
    if (40 <= shiftLeft) revert UIntOutOfBounds(); // 10**56 < FIX_MAX < 10**57

    shiftLeft += 18;

    uint256 coeff = 10**abs(shiftLeft);
    uint256 shifted = (shiftLeft >= 0) ? x * coeff : _divrnd(x, coeff, rounding);

    return _safeWrap(shifted);
}

/// Divide a uint by a uint192, yielding a uint192
/// This may also fail if the result is MIN_uint192! not fixing this for optimization's sake.
/// @return x / y
// as-ints: x * 1e36 / y
function divFix(uint256 x, uint192 y) pure returns (uint192) {
    // If we didn't have to worry about overflow, we'd just do `return x * 1e36 / _y`
    // If it's safe to do this operation the easy way, do it:
    if (x < uint256(type(uint256).max / FIX_SCALE_SQ)) {
        return _safeWrap(uint256(x * FIX_SCALE_SQ) / y);
    } else {
        return _safeWrap(mulDiv256(x, FIX_SCALE_SQ, y));
    }
}

/// Divide a uint by a uint, yielding a  uint192
/// @return x / y
// as-ints: x * 1e18 / y
function divuu(uint256 x, uint256 y) pure returns (uint192) {
    return _safeWrap(mulDiv256(FIX_SCALE, x, y));
}

/// @return min(x,y)
// as-ints: min(x,y)
function fixMin(uint192 x, uint192 y) pure returns (uint192) {
    return x < y ? x : y;
}

/// @return max(x,y)
// as-ints: max(x,y)
function fixMax(uint192 x, uint192 y) pure returns (uint192) {
    return x > y ? x : y;
}

/// @return absoluteValue(x,y)
// as-ints: absoluteValue(x,y)
function abs(int256 x) pure returns (uint256) {
    return x < 0 ? uint256(-x) : uint256(x);
}

/// Divide two uints, returning a uint, using rounding mode `rounding`.
/// @return numerator / divisor
// as-ints: numerator / divisor
function _divrnd(
    uint256 numerator,
    uint256 divisor,
    RoundingMode rounding
) pure returns (uint256) {
    uint256 result = numerator / divisor;

    if (rounding == FLOOR) return result;

    if (rounding == ROUND) {
        if (numerator % divisor > (divisor - 1) / 2) {
            result++;
        }
    } else {
        if (numerator % divisor > 0) {
            result++;
        }
    }

    return result;
}

library FixLib {
    /// Again, all arithmetic functions fail if and only if the result is out of bounds.

    /// Convert this fixed-point value to a uint. Round towards zero if needed.
    /// @return x
    // as-ints: x / 1e18
    function toUint(uint192 x) internal pure returns (uint136) {
        return toUint(x, FLOOR);
    }

    /// Convert this uint192 to a uint
    /// @return x
    // as-ints: x / 1e18 with rounding
    function toUint(uint192 x, RoundingMode rounding) internal pure returns (uint136) {
        return uint136(_divrnd(uint256(x), FIX_SCALE, rounding));
    }

    /// Return the uint192 shifted to the left by `decimal` digits
    /// (Similar to a bitshift but in base 10)
    /// @return x * 10**decimals
    // as-ints: x * 10**decimals
    function shiftl(uint192 x, int8 decimals) internal pure returns (uint192) {
        return shiftl(x, decimals, FLOOR);
    }

    /// Return the uint192 shifted to the left by `decimal` digits
    /// (Similar to a bitshift but in base 10)
    /// @return x * 10**decimals
    // as-ints: x * 10**decimals
    function shiftl(
        uint192 x,
        int8 decimals,
        RoundingMode rounding
    ) internal pure returns (uint192) {
        // Handle overflow cases
        if (x == 0) return 0;
        if (decimals <= -59) return (rounding == CEIL ? 1 : 0); // 59, because 1e58 > 2**192
        if (58 <= decimals) revert UIntOutOfBounds(); // 58, because x * 1e58 > 2 ** 192 if x != 0

        uint256 coeff = uint256(10**abs(decimals));
        return _safeWrap(decimals >= 0 ? x * coeff : _divrnd(x, coeff, rounding));
    }

    /// Add a uint192 to this uint192
    /// @return x + y
    // as-ints: x + y
    function plus(uint192 x, uint192 y) internal pure returns (uint192) {
        return x + y;
    }

    /// Add a uint to this uint192
    /// @return x + y
    // as-ints: x + y*1e18
    function plusu(uint192 x, uint256 y) internal pure returns (uint192) {
        return _safeWrap(x + y * FIX_SCALE);
    }

    /// Subtract a uint192 from this uint192
    /// @return x - y
    // as-ints: x - y
    function minus(uint192 x, uint192 y) internal pure returns (uint192) {
        return x - y;
    }

    /// Subtract a uint from this uint192
    /// @return x - y
    // as-ints: x - y*1e18
    function minusu(uint192 x, uint256 y) internal pure returns (uint192) {
        return _safeWrap(uint256(x) - uint256(y * FIX_SCALE));
    }

    /// Multiply this uint192 by a uint192
    /// Round truncated values to the nearest available value. 5e-19 rounds away from zero.
    /// @return x * y
    // as-ints: x * y/1e18  [division using ROUND, not FLOOR]
    function mul(uint192 x, uint192 y) internal pure returns (uint192) {
        return mul(x, y, ROUND);
    }

    /// Multiply this uint192 by a uint192
    /// @return x * y
    // as-ints: x * y/1e18
    function mul(
        uint192 x,
        uint192 y,
        RoundingMode rounding
    ) internal pure returns (uint192) {
        return _safeWrap(_divrnd(uint256(x) * uint256(y), FIX_SCALE, rounding));
    }

    /// Multiply this uint192 by a uint
    /// @return x * y
    // as-ints: x * y
    function mulu(uint192 x, uint256 y) internal pure returns (uint192) {
        return _safeWrap(x * y);
    }

    /// Divide this uint192 by a uint192
    /// @return x / y
    // as-ints: x * 1e18 / y
    function div(uint192 x, uint192 y) internal pure returns (uint192) {
        return div(x, y, FLOOR);
    }

    /// Divide this uint192 by a uint192
    /// @return x / y
    // as-ints: x * 1e18 / y
    function div(
        uint192 x,
        uint192 y,
        RoundingMode rounding
    ) internal pure returns (uint192) {
        // Multiply-in FIX_SCALE before dividing by y to preserve precision.
        return _safeWrap(_divrnd(uint256(x) * FIX_SCALE, y, rounding));
    }

    /// Divide this uint192 by a uint
    /// @return x / y
    // as-ints: x / y
    function divu(uint192 x, uint256 y) internal pure returns (uint192) {
        return divu(x, y, FLOOR);
    }

    /// Divide this uint192 by a uint
    /// @return x / y
    // as-ints: x / y
    function divu(
        uint192 x,
        uint256 y,
        RoundingMode rounding
    ) internal pure returns (uint192) {
        return _safeWrap(_divrnd(x, y, rounding));
    }

    uint64 constant FIX_HALF = uint64(FIX_SCALE) / 2;

    /// Raise this uint192 to a nonnegative integer power. Requires that x_ <= FIX_ONE
    /// Gas cost is O(lg(y)), precision is +- 1e-18.
    /// @return x_ ** y
    // as-ints: x_ ** y / 1e18**(y-1)    <- technically correct for y = 0. :D
    function powu(uint192 x_, uint48 y) internal pure returns (uint192) {
        require(x_ <= FIX_ONE);
        if (y == 1) return x_;
        if (x_ == FIX_ONE || y == 0) return FIX_ONE;
        uint256 x = uint256(x_) * FIX_SCALE; // x is D36
        uint256 result = FIX_SCALE_SQ; // result is D36
        while (true) {
            if (y & 1 == 1) result = (result * x + FIX_SCALE_SQ / 2) / FIX_SCALE_SQ;
            if (y <= 1) break;
            y = (y >> 1);
            x = (x * x + FIX_SCALE_SQ / 2) / FIX_SCALE_SQ;
        }
        return _safeWrap(result / FIX_SCALE);
    }

    /// Comparison operators...
    function lt(uint192 x, uint192 y) internal pure returns (bool) {
        return x < y;
    }

    function lte(uint192 x, uint192 y) internal pure returns (bool) {
        return x <= y;
    }

    function gt(uint192 x, uint192 y) internal pure returns (bool) {
        return x > y;
    }

    function gte(uint192 x, uint192 y) internal pure returns (bool) {
        return x >= y;
    }

    function eq(uint192 x, uint192 y) internal pure returns (bool) {
        return x == y;
    }

    function neq(uint192 x, uint192 y) internal pure returns (bool) {
        return x != y;
    }

    /// Return whether or not this uint192 is less than epsilon away from y.
    /// @return |x - y| < epsilon
    // as-ints: |x - y| < epsilon
    function near(
        uint192 x,
        uint192 y,
        uint192 epsilon
    ) internal pure returns (bool) {
        uint192 diff = x <= y ? y - x : x - y;
        return diff < epsilon;
    }

    // ================ Chained Operations ================
    // The operation foo_bar() always means:
    //   Do foo() followed by bar(), and overflow only if the _end_ result doesn't fit in an uint192

    /// Shift this uint192 left by `decimals` digits, and convert to a uint
    /// @return x * 10**decimals
    // as-ints: x * 10**(decimals - 18)
    function shiftl_toUint(uint192 x, int8 decimals) internal pure returns (uint256) {
        return shiftl_toUint(x, decimals, FLOOR);
    }

    /// Shift this uint192 left by `decimals` digits, and convert to a uint.
    /// @return x * 10**decimals
    // as-ints: x * 10**(decimals - 18)
    function shiftl_toUint(
        uint192 x,
        int8 decimals,
        RoundingMode rounding
    ) internal pure returns (uint256) {
        // Handle overflow cases
        if (x == 0) return 0; // always computable, no matter what decimals is
        if (decimals <= -42) return (rounding == CEIL ? 1 : 0);
        if (96 <= decimals) revert UIntOutOfBounds();

        decimals -= 18; // shift so that toUint happens at the same time.

        uint256 coeff = uint256(10**abs(decimals));
        return decimals >= 0 ? uint256(x * coeff) : uint256(_divrnd(x, coeff, rounding));
    }

    /// Multiply this uint192 by a uint, and output the result as a uint
    /// @return x * y
    // as-ints: x * y / 1e18
    function mulu_toUint(uint192 x, uint256 y) internal pure returns (uint256) {
        return mulDiv256(uint256(x), y, FIX_SCALE);
    }

    /// Multiply this uint192 by a uint, and output the result as a uint
    /// @return x * y
    // as-ints: x * y / 1e18
    function mulu_toUint(
        uint192 x,
        uint256 y,
        RoundingMode rounding
    ) internal pure returns (uint256) {
        return mulDiv256(uint256(x), y, FIX_SCALE, rounding);
    }

    /// Multiply this uint192 by a uint192 and output the result as a uint
    /// @return x * y
    // as-ints: x * y / 1e36
    function mul_toUint(uint192 x, uint192 y) internal pure returns (uint256) {
        return mulDiv256(uint256(x), uint256(y), FIX_SCALE_SQ);
    }

    /// Multiply this uint192 by a uint192 and output the result as a uint
    /// @return x * y
    // as-ints: x * y / 1e36
    function mul_toUint(
        uint192 x,
        uint192 y,
        RoundingMode rounding
    ) internal pure returns (uint256) {
        return mulDiv256(uint256(x), uint256(y), FIX_SCALE_SQ, rounding);
    }

    /// Compute x * y / z avoiding intermediate overflow
    /// @dev Only use if you need to avoid overflow; costlier than x * y / z
    /// @return x * y / z
    // as-ints: x * y / z
    function muluDivu(
        uint192 x,
        uint256 y,
        uint256 z
    ) internal pure returns (uint192) {
        return muluDivu(x, y, z, FLOOR);
    }

    /// Compute x * y / z, avoiding intermediate overflow
    /// @dev Only use if you need to avoid overflow; costlier than x * y / z
    /// @return x * y / z
    // as-ints: x * y / z
    function muluDivu(
        uint192 x,
        uint256 y,
        uint256 z,
        RoundingMode rounding
    ) internal pure returns (uint192) {
        return _safeWrap(mulDiv256(x, y, z, rounding));
    }

    /// Compute x * y / z on Fixes, avoiding intermediate overflow
    /// @dev Only use if you need to avoid overflow; costlier than x * y / z
    /// @return x * y / z
    // as-ints: x * y / z
    function mulDiv(
        uint192 x,
        uint192 y,
        uint192 z
    ) internal pure returns (uint192) {
        return mulDiv(x, y, z, FLOOR);
    }

    /// Compute x * y / z on Fixes, avoiding intermediate overflow
    /// @dev Only use if you need to avoid overflow; costlier than x * y / z
    /// @return x * y / z
    // as-ints: x * y / z
    function mulDiv(
        uint192 x,
        uint192 y,
        uint192 z,
        RoundingMode rounding
    ) internal pure returns (uint192) {
        return _safeWrap(mulDiv256(x, y, z, rounding));
    }

    // === safe*() ===

    /// Multiply two fixes, rounding up to FIX_MAX and down to 0
    /// @param a First param to multiply
    /// @param b Second param to multiply
    function safeMul(
        uint192 a,
        uint192 b,
        RoundingMode rounding
    ) internal pure returns (uint192) {
        // untestable:
        //      a will never = 0 here because of the check in _price()
        if (a == 0 || b == 0) return 0;
        // untestable:
        //      a = FIX_MAX iff b = 0
        if (a == FIX_MAX || b == FIX_MAX) return FIX_MAX;

        // return FIX_MAX instead of throwing overflow errors.
        unchecked {
            // p and mul *are* Fix values, so have 18 decimals (D18)
            uint256 rawDelta = uint256(b) * a; // {D36} = {D18} * {D18}
            // if we overflowed, then return FIX_MAX
            if (rawDelta / b != a) return FIX_MAX;
            uint256 shiftDelta = rawDelta;

            // add in rounding
            if (rounding == RoundingMode.ROUND) shiftDelta += (FIX_ONE / 2);
            else if (rounding == RoundingMode.CEIL) shiftDelta += FIX_ONE - 1;

            // untestable (here there be dragons):
            // (below explanation is for the ROUND case, but it extends to the FLOOR/CEIL too)
            //          A)  shiftDelta = rawDelta + (FIX_ONE / 2)
            //      shiftDelta overflows if:
            //          B)  shiftDelta = MAX_UINT256 - FIX_ONE/2 + 1
            //              rawDelta + (FIX_ONE/2) = MAX_UINT256 - FIX_ONE/2 + 1
            //              b * a = MAX_UINT256 - FIX_ONE + 1
            //      therefore shiftDelta overflows if:
            //          C)  b = (MAX_UINT256 - FIX_ONE + 1) / a
            //      MAX_UINT256 ~= 1e77 , FIX_MAX ~= 6e57 (6e20 difference in magnitude)
            //      a <= 1e21 (MAX_TARGET_AMT)
            //      a must be between 1e19 & 1e20 in order for b in (C) to be uint192,
            //      but a would have to be < 1e18 in order for (A) to overflow
            if (shiftDelta < rawDelta) return FIX_MAX;

            // return FIX_MAX if return result would truncate
            if (shiftDelta / FIX_ONE > FIX_MAX) return FIX_MAX;

            // return _div(rawDelta, FIX_ONE, rounding)
            return uint192(shiftDelta / FIX_ONE); // {D18} = {D36} / {D18}
        }
    }
}

// ================ a couple pure-uint helpers================
// as-ints comments are omitted here, because they're the same as @return statements, because
// these are all pure uint functions

/// Return (x*y/z), avoiding intermediate overflow.
//  Adapted from sources:
//    https://medium.com/coinmonks/4db014e080b1, https://medium.com/wicketh/afa55870a65
//    and quite a few of the other excellent "Mathemagic" posts from https://medium.com/wicketh
/// @dev Only use if you need to avoid overflow; costlier than x * y / z
/// @return result x * y / z
function mulDiv256(
    uint256 x,
    uint256 y,
    uint256 z
) pure returns (uint256 result) {
    unchecked {
        (uint256 hi, uint256 lo) = fullMul(x, y);
        if (hi >= z) revert UIntOutOfBounds();
        uint256 mm = mulmod(x, y, z);
        if (mm > lo) hi -= 1;
        lo -= mm;
        uint256 pow2 = z & (0 - z);
        z /= pow2;
        lo /= pow2;
        lo += hi * ((0 - pow2) / pow2 + 1);
        uint256 r = 1;
        r *= 2 - z * r;
        r *= 2 - z * r;
        r *= 2 - z * r;
        r *= 2 - z * r;
        r *= 2 - z * r;
        r *= 2 - z * r;
        r *= 2 - z * r;
        r *= 2 - z * r;
        result = lo * r;
    }
}

/// Return (x*y/z), avoiding intermediate overflow.
/// @dev Only use if you need to avoid overflow; costlier than x * y / z
/// @return x * y / z
function mulDiv256(
    uint256 x,
    uint256 y,
    uint256 z,
    RoundingMode rounding
) pure returns (uint256) {
    uint256 result = mulDiv256(x, y, z);
    if (rounding == FLOOR) return result;

    uint256 mm = mulmod(x, y, z);
    if (rounding == CEIL) {
        if (mm > 0) result += 1;
    } else {
        if (mm > ((z - 1) / 2)) result += 1; // z should be z-1
    }
    return result;
}

/// Return (x*y) as a "virtual uint512" (lo, hi), representing (hi*2**256 + lo)
///   Adapted from sources:
///   https://medium.com/wicketh/27650fec525d, https://medium.com/coinmonks/4db014e080b1
/// @dev Intended to be internal to this library
/// @return hi (hi, lo) satisfies  hi*(2**256) + lo == x * y
/// @return lo (paired with `hi`)
function fullMul(uint256 x, uint256 y) pure returns (uint256 hi, uint256 lo) {
    unchecked {
        uint256 mm = mulmod(x, y, uint256(0) - uint256(1));
        lo = x * y;
        hi = mm - lo;
        if (mm < lo) hi -= 1;
    }
}

// File: contracts/libraries/Throttle.sol



// SPDX-License-Identifier: BlueOak-1.0.0
pragma solidity 0.8.17;

import "./Fixed.sol";

uint48 constant ONE_HOUR = 3600; // {seconds/hour}

/**
 * @title ThrottleLib
 * A library that implements a usage throttle that can be used to ensure net issuance
 * or net redemption for an RToken never exceeds some bounds per unit time (hour).
 *
 * It is expected for the RToken to use this library with two instances, one for issuance
 * and one for redemption. Issuance causes the available redemption amount to increase, and
 * visa versa.
 */
library ThrottleLib {
    using FixLib for uint192;

    struct Params {
        uint256 amtRate; // {qRTok/hour} a quantity of RToken hourly; cannot be 0
        uint192 pctRate; // {1/hour} a fraction of RToken hourly; can be 0
    }

    struct Throttle {
        // === Gov params ===
        Params params;
        // === Cache ===
        uint48 lastTimestamp; // {seconds}
        uint256 lastAvailable; // {qRTok}
    }

    /// Reverts if usage amount exceeds available amount
    /// @param supply {qRTok} Total RToken supply beforehand
    /// @param amount {qRTok} Amount of RToken to use. Should be negative for the issuance
    ///   throttle during redemption and for the redemption throttle during issuance.
    function useAvailable(
        Throttle storage throttle,
        uint256 supply,
        int256 amount
    ) internal {
        // untestable: amtRate will always be greater > 0 due to previous validations
        if (throttle.params.amtRate == 0 && throttle.params.pctRate == 0) return;

        // Calculate hourly limit
        uint256 limit = hourlyLimit(throttle, supply); // {qRTok}

        // Calculate available amount before supply change
        uint256 available = currentlyAvailable(throttle, limit);

        // Calculate available amount after supply change
        if (amount > 0) {
            require(uint256(amount) <= available, "supply change throttled");
            available -= uint256(amount);
            // untestable: the final else statement, amount will never be 0
        } else if (amount < 0) {
            available += uint256(-amount);
        }

        // Update cached values
        throttle.lastAvailable = available;
        throttle.lastTimestamp = uint48(block.timestamp);
    }

    /// @param limit {qRTok/hour} The hourly limit
    /// @return available {qRTok} Amount currently available for consumption
    function currentlyAvailable(Throttle storage throttle, uint256 limit)
        internal
        view
        returns (uint256 available)
    {
        uint48 delta = uint48(block.timestamp) - throttle.lastTimestamp; // {seconds}
        available = throttle.lastAvailable + (limit * delta) / ONE_HOUR;
        if (available > limit) available = limit;
    }

    /// @return limit {qRTok} The hourly limit
    function hourlyLimit(Throttle storage throttle, uint256 supply)
        internal
        view
        returns (uint256 limit)
    {
        Params storage params = throttle.params;

        // Calculate hourly limit as: max(params.amtRate, supply.mul(params.pctRate))
        limit = (supply * params.pctRate) / FIX_ONE_256; // {qRTok}
        if (params.amtRate > limit) limit = params.amtRate;
    }
}