// File: src/v0.8/ConfirmedOwner.sol



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

import "./ConfirmedOwnerWithProposal.sol";

/**
 * @title The ConfirmedOwner contract
 * @notice A contract with helpers for basic contract ownership.
 */
contract ConfirmedOwner is ConfirmedOwnerWithProposal {
  constructor(address newOwner) ConfirmedOwnerWithProposal(newOwner, address(0)) {}
}

// File: src/v0.8/ConfirmedOwnerWithProposal.sol



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

import "./interfaces/OwnableInterface.sol";

/**
 * @title The ConfirmedOwner contract
 * @notice A contract with helpers for basic contract ownership.
 */
contract ConfirmedOwnerWithProposal is OwnableInterface {
  address private s_owner;
  address private s_pendingOwner;

  event OwnershipTransferRequested(address indexed from, address indexed to);
  event OwnershipTransferred(address indexed from, address indexed to);

  constructor(address newOwner, address pendingOwner) {
    require(newOwner != address(0), "Cannot set owner to zero");

    s_owner = newOwner;
    if (pendingOwner != address(0)) {
      _transferOwnership(pendingOwner);
    }
  }

  /**
   * @notice Allows an owner to begin transferring ownership to a new address,
   * pending.
   */
  function transferOwnership(address to) public override onlyOwner {
    _transferOwnership(to);
  }

  /**
   * @notice Allows an ownership transfer to be completed by the recipient.
   */
  function acceptOwnership() external override {
    require(msg.sender == s_pendingOwner, "Must be proposed owner");

    address oldOwner = s_owner;
    s_owner = msg.sender;
    s_pendingOwner = address(0);

    emit OwnershipTransferred(oldOwner, msg.sender);
  }

  /**
   * @notice Get the current owner
   */
  function owner() public view override returns (address) {
    return s_owner;
  }

  /**
   * @notice validate, transfer ownership, and emit relevant events
   */
  function _transferOwnership(address to) private {
    require(to != msg.sender, "Cannot transfer to self");

    s_pendingOwner = to;

    emit OwnershipTransferRequested(s_owner, to);
  }

  /**
   * @notice validate access
   */
  function _validateOwnership() internal view {
    require(msg.sender == s_owner, "Only callable by owner");
  }

  /**
   * @notice Reverts if called by anyone other than the contract owner.
   */
  modifier onlyOwner() {
    _validateOwnership();
    _;
  }
}

// File: src/v0.8/dev/automation/upkeeps/LinkAvailableBalanceMonitor.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.8.6;

import "../../../ConfirmedOwner.sol";
import "../../../interfaces/automation/KeeperCompatibleInterface.sol";
import "../../../vendor/openzeppelin-solidity/v4.7.0/contracts/security/Pausable.sol";
import "../../../vendor/openzeppelin-solidity/v4.7.0/contracts/token/ERC20/IERC20.sol";
import "../../../vendor/openzeppelin-solidity/v4.7.3/contracts/utils/structs/EnumerableMap.sol";

interface IAggregatorProxy {
  function aggregator() external view returns (address);
}

interface ILinkAvailable {
  function linkAvailableForPayment() external view returns (int256 availableBalance);
}

/**
 * @title The LinkAvailableBalanceMonitor contract.
 * @notice A keeper-compatible contract that monitors target contracts for balance from a custom
 * function linkAvailableForPayment() and funds them with LINK if it falls below a defined
 * threshold. Also supports aggregator proxy contracts monitoring which require fetching the actual
 * target contract through a predefined interface.
 * @dev with 30 addresses as the MAX_PERFORM, the measured max gas usage of performUpkeep is around 2M
 * therefore, we recommend an upkeep gas limit of 3M (this has a 33% margin of safety). Although, nothing
 * prevents us from using 5M gas and increasing MAX_PERFORM, 30 seems like a reasonable batch size that
 * is probably plenty for most needs.
 * @dev with 130 addresses as the MAX_CHECK, the measured max gas usage of checkUpkeep is around 3.5M,
 * which is 30% below the 5M limit.
 * Note that testing conditions DO NOT match live chain gas usage, hence the margins. Change
 * at your own risk!!!
 * @dev some areas for improvement / acknowledgement of limitations:
 * * validate that all addresses conform to interface when adding them to the watchlist
 * * this is a "trusless" upkeep, meaning it does not trust the caller of performUpkeep;
     we could save a fair amount of gas and re-write this upkeep for use with Automation v2.0+,
     which has significantly different trust assumptions
 */
contract LinkAvailableBalanceMonitor is ConfirmedOwner, Pausable, KeeperCompatibleInterface {
  using EnumerableMap for EnumerableMap.AddressToUintMap;

  event FundsWithdrawn(uint256 amountWithdrawn, address payee);
  event TopUpSucceeded(address indexed topUpAddress);
  event TopUpBlocked(address indexed topUpAddress);
  event WatchlistUpdated();

  error InvalidWatchList();
  error DuplicateAddress(address duplicate);

  uint256 public constant MAX_PERFORM = 30; // max number to addresses to top up in a single batch
  uint256 public constant MAX_CHECK = 130; // max number of upkeeps to check (need to fit in 5M gas limit)
  IERC20 public immutable LINK_TOKEN;

  EnumerableMap.AddressToUintMap private s_watchList;
  uint256 private s_topUpAmount;

  /**
   * @param linkTokenAddress the LINK token address
   * @param topUpAmount the amount of LINK to top up an aggregator with at once
   */
  constructor(address linkTokenAddress, uint256 topUpAmount) ConfirmedOwner(msg.sender) {
    require(linkTokenAddress != address(0));
    require(topUpAmount > 0);
    LINK_TOKEN = IERC20(linkTokenAddress);
    s_topUpAmount = topUpAmount;
  }

  /**
   * @notice Sets the list of subscriptions to watch and their funding parameters
   * @param addresses the list of target addresses to watch (could be direct target or IAggregatorProxy)
   * @param minBalances the list of corresponding minBalance for the target address
   */
  function setWatchList(address[] calldata addresses, uint256[] calldata minBalances) external onlyOwner {
    if (addresses.length != minBalances.length) {
      revert InvalidWatchList();
    }
    // first, remove all existing addresses from list
    for (uint256 idx = s_watchList.length(); idx > 0; idx--) {
      (address target, ) = s_watchList.at(idx - 1);
      require(s_watchList.remove(target));
    }
    // then set new addresses
    for (uint256 idx = 0; idx < addresses.length; idx++) {
      if (s_watchList.contains(addresses[idx])) {
        revert DuplicateAddress(addresses[idx]);
      }
      if (addresses[idx] == address(0)) {
        revert InvalidWatchList();
      }
      s_watchList.set(addresses[idx], minBalances[idx]);
    }
    emit WatchlistUpdated();
  }

  /**
   * @notice Adds addresses to the watchlist without overwriting existing members
   * @param addresses the list of target addresses to watch (could be direct target or IAggregatorProxy)
   * @param minBalances the list of corresponding minBalance for the target address
   */
  function addToWatchList(address[] calldata addresses, uint256[] calldata minBalances) external onlyOwner {
    if (addresses.length != minBalances.length) {
      revert InvalidWatchList();
    }
    for (uint256 idx = 0; idx < addresses.length; idx++) {
      if (s_watchList.contains(addresses[idx])) {
        revert DuplicateAddress(addresses[idx]);
      }
      if (addresses[idx] == address(0)) {
        revert InvalidWatchList();
      }
      s_watchList.set(addresses[idx], minBalances[idx]);
    }
    emit WatchlistUpdated();
  }

  /**
   * @notice Removes addresses from the watchlist
   * @param addresses the list of target addresses to remove from the watchlist
   */
  function removeFromWatchlist(address[] calldata addresses) external onlyOwner {
    for (uint256 idx = 0; idx < addresses.length; idx++) {
      if (!s_watchList.contains(addresses[idx])) {
        revert InvalidWatchList();
      }
      s_watchList.remove(addresses[idx]);
    }
    emit WatchlistUpdated();
  }

  /**
   * @notice Gets a list of proxies that are underfunded, up to the MAX_PERFORM size
   * @dev the function starts at a random index in the list to avoid biasing the first
   * addresses in the list over latter ones.
   * @dev the function will check at most MAX_CHECK proxies in a single call
   * @dev the function returns a list with a max length of MAX_PERFORM
   * @return list of target addresses which are underfunded
   */
  function sampleUnderfundedAddresses() public view returns (address[] memory) {
    uint256 numTargets = s_watchList.length();
    uint256 numChecked = 0;
    uint256 idx = uint256(blockhash(block.number - 1)) % numTargets; // start at random index, to distribute load
    uint256 numToCheck = numTargets < MAX_CHECK ? numTargets : MAX_CHECK;
    uint256 numFound = 0;
    address[] memory targetsToFund = new address[](MAX_PERFORM);
    for (; numChecked < numToCheck; (idx, numChecked) = ((idx + 1) % numTargets, numChecked + 1)) {
      (address target, uint256 minBalance) = s_watchList.at(idx);
      (bool needsFunding, ) = _needsFunding(target, minBalance);
      if (needsFunding) {
        targetsToFund[numFound] = target;
        numFound++;
        if (numFound == MAX_PERFORM) {
          break; // max number of addresses in batch reached
        }
      }
    }
    if (numFound != MAX_PERFORM) {
      assembly {
        mstore(targetsToFund, numFound) // resize array to number of valid targets
      }
    }
    return targetsToFund;
  }

  /**
   * @notice Send funds to the targets provided.
   * @param targetAddresses the list of targets to fund
   */
  function topUp(address[] memory targetAddresses) public whenNotPaused {
    uint256 topUpAmount = s_topUpAmount;
    uint256 stopIdx = targetAddresses.length;
    uint256 numCanFund = LINK_TOKEN.balanceOf(address(this)) / topUpAmount;
    stopIdx = numCanFund < stopIdx ? numCanFund : stopIdx;
    for (uint256 idx = 0; idx < stopIdx; idx++) {
      (bool exists, uint256 minBalance) = s_watchList.tryGet(targetAddresses[idx]);
      if (!exists) {
        emit TopUpBlocked(targetAddresses[idx]);
        continue;
      }
      (bool needsFunding, address target) = _needsFunding(targetAddresses[idx], minBalance);
      if (!needsFunding) {
        emit TopUpBlocked(targetAddresses[idx]);
        continue;
      }
      LINK_TOKEN.transfer(target, topUpAmount);
      emit TopUpSucceeded(targetAddresses[idx]);
    }
  }

  /**
   * @notice Gets list of subscription ids that are underfunded and returns a keeper-compatible payload.
   * @return upkeepNeeded signals if upkeep is needed
   * @return performData is an abi encoded list of subscription ids that need funds
   */
  function checkUpkeep(
    bytes calldata
  ) external view override whenNotPaused returns (bool upkeepNeeded, bytes memory performData) {
    address[] memory needsFunding = sampleUnderfundedAddresses();
    uint256 numCanFund = LINK_TOKEN.balanceOf(address(this)) / s_topUpAmount;
    if (numCanFund < needsFunding.length) {
      assembly {
        mstore(needsFunding, numCanFund) // resize
      }
    }
    upkeepNeeded = needsFunding.length > 0;
    performData = abi.encode(needsFunding);
    return (upkeepNeeded, performData);
  }

  /**
   * @notice Called by the keeper to send funds to underfunded addresses.
   * @param performData the abi encoded list of addresses to fund
   */
  function performUpkeep(bytes calldata performData) external override {
    address[] memory needsFunding = abi.decode(performData, (address[]));
    topUp(needsFunding);
  }

  /**
   * @notice Withdraws the contract balance in the LINK token.
   * @param amount the amount of the LINK to withdraw
   * @param payee the address to pay
   */
  function withdraw(uint256 amount, address payable payee) external onlyOwner {
    require(payee != address(0));
    LINK_TOKEN.transfer(payee, amount);
    emit FundsWithdrawn(amount, payee);
  }

  /**
   * @notice Sets the top up amount
   */
  function setTopUpAmount(uint256 topUpAmount) external onlyOwner returns (uint256) {
    require(topUpAmount > 0);
    return s_topUpAmount = topUpAmount;
  }

  /**
   * @notice Sets the minimum balance for the given target address
   */
  function setMinBalance(address target, uint256 minBalance) external onlyOwner returns (uint256) {
    require(minBalance > 0);
    (bool exists, uint256 prevMinBalance) = s_watchList.tryGet(target);
    if (!exists) {
      revert InvalidWatchList();
    }
    s_watchList.set(target, minBalance);
    return prevMinBalance;
  }

  /**
   * @notice Pause the contract, which prevents executing performUpkeep
   */
  function pause() external onlyOwner {
    _pause();
  }

  /**
   * @notice Unpause the contract
   */
  function unpause() external onlyOwner {
    _unpause();
  }

  /**
   * @notice Gets the list of subscription ids being watched
   */
  function getWatchList() external view returns (address[] memory, uint256[] memory) {
    uint256 len = s_watchList.length();
    address[] memory targets = new address[](len);
    uint256[] memory minBalances = new uint256[](len);

    for (uint256 idx = 0; idx < len; idx++) {
      (targets[idx], minBalances[idx]) = s_watchList.at(idx);
    }

    return (targets, minBalances);
  }

  /**
   * @notice Gets the configured top up amount
   */
  function getTopUpAmount() external view returns (uint256) {
    return s_topUpAmount;
  }

  /**
   * @notice Gets the configured minimum balance for the given target
   */
  function getMinBalance(address target) external view returns (uint256) {
    (bool exists, uint256 minBalance) = s_watchList.tryGet(target);
    if (!exists) {
      revert InvalidWatchList();
    }
    return minBalance;
  }

  /**
   * @notice checks the target (could be direct target or IAggregatorProxy), and determines
   * if it is elligible for funding
   * @param targetAddress the target to check
   * @param minBalance minimum balance required for the target
   * @return bool whether the target needs funding or not
   * @return address the address of the contract needing funding
   */
  function _needsFunding(address targetAddress, uint256 minBalance) private view returns (bool, address) {
    ILinkAvailable target;
    IAggregatorProxy proxy = IAggregatorProxy(targetAddress);
    try proxy.aggregator() returns (address aggregatorAddress) {
      target = ILinkAvailable(aggregatorAddress);
    } catch {
      target = ILinkAvailable(targetAddress);
    }
    try target.linkAvailableForPayment() returns (int256 balance) {
      if (balance < 0 || uint256(balance) < minBalance) {
        return (true, address(target));
      }
    } catch {}
    return (false, address(0));
  }
}

// File: src/v0.8/interfaces/OwnableInterface.sol



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

interface OwnableInterface {
  function owner() external returns (address);

  function transferOwnership(address recipient) external;

  function acceptOwnership() external;
}

// File: src/v0.8/interfaces/automation/AutomationCompatibleInterface.sol



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

interface AutomationCompatibleInterface {
  /**
   * @notice method that is simulated by the keepers to see if any work actually
   * needs to be performed. This method does does not actually need to be
   * executable, and since it is only ever simulated it can consume lots of gas.
   * @dev To ensure that it is never called, you may want to add the
   * cannotExecute modifier from KeeperBase to your implementation of this
   * method.
   * @param checkData specified in the upkeep registration so it is always the
   * same for a registered upkeep. This can easily be broken down into specific
   * arguments using `abi.decode`, so multiple upkeeps can be registered on the
   * same contract and easily differentiated by the contract.
   * @return upkeepNeeded boolean to indicate whether the keeper should call
   * performUpkeep or not.
   * @return performData bytes that the keeper should call performUpkeep with, if
   * upkeep is needed. If you would like to encode data to decode later, try
   * `abi.encode`.
   */
  function checkUpkeep(bytes calldata checkData) external returns (bool upkeepNeeded, bytes memory performData);

  /**
   * @notice method that is actually executed by the keepers, via the registry.
   * The data returned by the checkUpkeep simulation will be passed into
   * this method to actually be executed.
   * @dev The input to this method should not be trusted, and the caller of the
   * method should not even be restricted to any single registry. Anyone should
   * be able call it, and the input should be validated, there is no guarantee
   * that the data passed in is the performData returned from checkUpkeep. This
   * could happen due to malicious keepers, racing keepers, or simply a state
   * change while the performUpkeep transaction is waiting for confirmation.
   * Always validate the data passed in.
   * @param performData is the data which was passed back from the checkData
   * simulation. If it is encoded, it can easily be decoded into other types by
   * calling `abi.decode`. This data should not be trusted, and should be
   * validated against the contract's current state.
   */
  function performUpkeep(bytes calldata performData) external;
}

// File: src/v0.8/interfaces/automation/KeeperCompatibleInterface.sol



// SPDX-License-Identifier: MIT
/**
 * @notice This is a deprecated interface. Please use AutomationCompatibleInterface directly.
 */
pragma solidity ^0.8.0;
import {AutomationCompatibleInterface as KeeperCompatibleInterface} from "./AutomationCompatibleInterface.sol";

// File: src/v0.8/vendor/openzeppelin-solidity/v4.7.0/contracts/security/Pausable.sol



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

pragma solidity ^0.8.0;

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

/**
 * @dev Contract module which allows children to implement an emergency stop
 * mechanism that can be triggered by an authorized account.
 *
 * This module is used through inheritance. It will make available the
 * modifiers `whenNotPaused` and `whenPaused`, which can be applied to
 * the functions of your contract. Note that they will not be pausable by
 * simply including this module, only once the modifiers are put in place.
 */
abstract contract Pausable is Context {
    /**
     * @dev Emitted when the pause is triggered by `account`.
     */
    event Paused(address account);

    /**
     * @dev Emitted when the pause is lifted by `account`.
     */
    event Unpaused(address account);

    bool private _paused;

    /**
     * @dev Initializes the contract in unpaused state.
     */
    constructor() {
        _paused = false;
    }

    /**
     * @dev Modifier to make a function callable only when the contract is not paused.
     *
     * Requirements:
     *
     * - The contract must not be paused.
     */
    modifier whenNotPaused() {
        _requireNotPaused();
        _;
    }

    /**
     * @dev Modifier to make a function callable only when the contract is paused.
     *
     * Requirements:
     *
     * - The contract must be paused.
     */
    modifier whenPaused() {
        _requirePaused();
        _;
    }

    /**
     * @dev Returns true if the contract is paused, and false otherwise.
     */
    function paused() public view virtual returns (bool) {
        return _paused;
    }

    /**
     * @dev Throws if the contract is paused.
     */
    function _requireNotPaused() internal view virtual {
        require(!paused(), "Pausable: paused");
    }

    /**
     * @dev Throws if the contract is not paused.
     */
    function _requirePaused() internal view virtual {
        require(paused(), "Pausable: not paused");
    }

    /**
     * @dev Triggers stopped state.
     *
     * Requirements:
     *
     * - The contract must not be paused.
     */
    function _pause() internal virtual whenNotPaused {
        _paused = true;
        emit Paused(_msgSender());
    }

    /**
     * @dev Returns to normal state.
     *
     * Requirements:
     *
     * - The contract must be paused.
     */
    function _unpause() internal virtual whenPaused {
        _paused = false;
        emit Unpaused(_msgSender());
    }
}

// File: src/v0.8/vendor/openzeppelin-solidity/v4.7.0/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: src/v0.8/vendor/openzeppelin-solidity/v4.7.0/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: src/v0.8/vendor/openzeppelin-solidity/v4.7.3/contracts/utils/structs/EnumerableMap.sol



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

pragma solidity ^0.8.0;

import "./EnumerableSet.sol";

/**
 * @dev Library for managing an enumerable variant of Solidity's
 * https://solidity.readthedocs.io/en/latest/types.html#mapping-types[`mapping`]
 * type.
 *
 * Maps have the following properties:
 *
 * - Entries are added, removed, and checked for existence in constant time
 * (O(1)).
 * - Entries are enumerated in O(n). No guarantees are made on the ordering.
 *
 * ```
 * contract Example {
 *     // Add the library methods
 *     using EnumerableMap for EnumerableMap.UintToAddressMap;
 *
 *     // Declare a set state variable
 *     EnumerableMap.UintToAddressMap private myMap;
 * }
 * ```
 *
 * The following map types are supported:
 *
 * - `uint256 -> address` (`UintToAddressMap`) since v3.0.0
 * - `address -> uint256` (`AddressToUintMap`) since v4.6.0
 * - `bytes32 -> bytes32` (`Bytes32ToBytes32`) since v4.6.0
 * - `uint256 -> uint256` (`UintToUintMap`) since v4.7.0
 * - `bytes32 -> uint256` (`Bytes32ToUintMap`) since v4.7.0
 *
 * [WARNING]
 * ====
 *  Trying to delete such a structure from storage will likely result in data corruption, rendering the structure unusable.
 *  See https://github.com/ethereum/solidity/pull/11843[ethereum/solidity#11843] for more info.
 *
 *  In order to clean an EnumerableMap, you can either remove all elements one by one or create a fresh instance using an array of EnumerableMap.
 * ====
 */
library EnumerableMap {
    using EnumerableSet for EnumerableSet.Bytes32Set;

    // To implement this library for multiple types with as little code
    // repetition as possible, we write it in terms of a generic Map type with
    // bytes32 keys and values.
    // The Map implementation uses private functions, and user-facing
    // implementations (such as Uint256ToAddressMap) are just wrappers around
    // the underlying Map.
    // This means that we can only create new EnumerableMaps for types that fit
    // in bytes32.

    struct Bytes32ToBytes32Map {
        // Storage of keys
        EnumerableSet.Bytes32Set _keys;
        mapping(bytes32 => bytes32) _values;
    }

    /**
     * @dev Adds a key-value pair to a map, or updates the value for an existing
     * key. O(1).
     *
     * Returns true if the key was added to the map, that is if it was not
     * already present.
     */
    function set(
        Bytes32ToBytes32Map storage map,
        bytes32 key,
        bytes32 value
    ) internal returns (bool) {
        map._values[key] = value;
        return map._keys.add(key);
    }

    /**
     * @dev Removes a key-value pair from a map. O(1).
     *
     * Returns true if the key was removed from the map, that is if it was present.
     */
    function remove(Bytes32ToBytes32Map storage map, bytes32 key) internal returns (bool) {
        delete map._values[key];
        return map._keys.remove(key);
    }

    /**
     * @dev Returns true if the key is in the map. O(1).
     */
    function contains(Bytes32ToBytes32Map storage map, bytes32 key) internal view returns (bool) {
        return map._keys.contains(key);
    }

    /**
     * @dev Returns the number of key-value pairs in the map. O(1).
     */
    function length(Bytes32ToBytes32Map storage map) internal view returns (uint256) {
        return map._keys.length();
    }

    /**
     * @dev Returns the key-value pair stored at position `index` in the map. O(1).
     *
     * Note that there are no guarantees on the ordering of entries inside the
     * array, and it may change when more entries are added or removed.
     *
     * Requirements:
     *
     * - `index` must be strictly less than {length}.
     */
    function at(Bytes32ToBytes32Map storage map, uint256 index) internal view returns (bytes32, bytes32) {
        bytes32 key = map._keys.at(index);
        return (key, map._values[key]);
    }

    /**
     * @dev Tries to returns the value associated with `key`.  O(1).
     * Does not revert if `key` is not in the map.
     */
    function tryGet(Bytes32ToBytes32Map storage map, bytes32 key) internal view returns (bool, bytes32) {
        bytes32 value = map._values[key];
        if (value == bytes32(0)) {
            return (contains(map, key), bytes32(0));
        } else {
            return (true, value);
        }
    }

    /**
     * @dev Returns the value associated with `key`.  O(1).
     *
     * Requirements:
     *
     * - `key` must be in the map.
     */
    function get(Bytes32ToBytes32Map storage map, bytes32 key) internal view returns (bytes32) {
        bytes32 value = map._values[key];
        require(value != 0 || contains(map, key), "EnumerableMap: nonexistent key");
        return value;
    }

    /**
     * @dev Same as {_get}, with a custom error message when `key` is not in the map.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {_tryGet}.
     */
    function get(
        Bytes32ToBytes32Map storage map,
        bytes32 key,
        string memory errorMessage
    ) internal view returns (bytes32) {
        bytes32 value = map._values[key];
        require(value != 0 || contains(map, key), errorMessage);
        return value;
    }

    // UintToUintMap

    struct UintToUintMap {
        Bytes32ToBytes32Map _inner;
    }

    /**
     * @dev Adds a key-value pair to a map, or updates the value for an existing
     * key. O(1).
     *
     * Returns true if the key was added to the map, that is if it was not
     * already present.
     */
    function set(
        UintToUintMap storage map,
        uint256 key,
        uint256 value
    ) internal returns (bool) {
        return set(map._inner, bytes32(key), bytes32(value));
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the key was removed from the map, that is if it was present.
     */
    function remove(UintToUintMap storage map, uint256 key) internal returns (bool) {
        return remove(map._inner, bytes32(key));
    }

    /**
     * @dev Returns true if the key is in the map. O(1).
     */
    function contains(UintToUintMap storage map, uint256 key) internal view returns (bool) {
        return contains(map._inner, bytes32(key));
    }

    /**
     * @dev Returns the number of elements in the map. O(1).
     */
    function length(UintToUintMap storage map) internal view returns (uint256) {
        return length(map._inner);
    }

    /**
     * @dev Returns the element stored at position `index` in the set. O(1).
     * Note that there are no guarantees on the ordering of values inside the
     * array, and it may change when more values are added or removed.
     *
     * Requirements:
     *
     * - `index` must be strictly less than {length}.
     */
    function at(UintToUintMap storage map, uint256 index) internal view returns (uint256, uint256) {
        (bytes32 key, bytes32 value) = at(map._inner, index);
        return (uint256(key), uint256(value));
    }

    /**
     * @dev Tries to returns the value associated with `key`.  O(1).
     * Does not revert if `key` is not in the map.
     */
    function tryGet(UintToUintMap storage map, uint256 key) internal view returns (bool, uint256) {
        (bool success, bytes32 value) = tryGet(map._inner, bytes32(key));
        return (success, uint256(value));
    }

    /**
     * @dev Returns the value associated with `key`.  O(1).
     *
     * Requirements:
     *
     * - `key` must be in the map.
     */
    function get(UintToUintMap storage map, uint256 key) internal view returns (uint256) {
        return uint256(get(map._inner, bytes32(key)));
    }

    /**
     * @dev Same as {get}, with a custom error message when `key` is not in the map.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryGet}.
     */
    function get(
        UintToUintMap storage map,
        uint256 key,
        string memory errorMessage
    ) internal view returns (uint256) {
        return uint256(get(map._inner, bytes32(key), errorMessage));
    }

    // UintToAddressMap

    struct UintToAddressMap {
        Bytes32ToBytes32Map _inner;
    }

    /**
     * @dev Adds a key-value pair to a map, or updates the value for an existing
     * key. O(1).
     *
     * Returns true if the key was added to the map, that is if it was not
     * already present.
     */
    function set(
        UintToAddressMap storage map,
        uint256 key,
        address value
    ) internal returns (bool) {
        return set(map._inner, bytes32(key), bytes32(uint256(uint160(value))));
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the key was removed from the map, that is if it was present.
     */
    function remove(UintToAddressMap storage map, uint256 key) internal returns (bool) {
        return remove(map._inner, bytes32(key));
    }

    /**
     * @dev Returns true if the key is in the map. O(1).
     */
    function contains(UintToAddressMap storage map, uint256 key) internal view returns (bool) {
        return contains(map._inner, bytes32(key));
    }

    /**
     * @dev Returns the number of elements in the map. O(1).
     */
    function length(UintToAddressMap storage map) internal view returns (uint256) {
        return length(map._inner);
    }

    /**
     * @dev Returns the element stored at position `index` in the set. O(1).
     * Note that there are no guarantees on the ordering of values inside the
     * array, and it may change when more values are added or removed.
     *
     * Requirements:
     *
     * - `index` must be strictly less than {length}.
     */
    function at(UintToAddressMap storage map, uint256 index) internal view returns (uint256, address) {
        (bytes32 key, bytes32 value) = at(map._inner, index);
        return (uint256(key), address(uint160(uint256(value))));
    }

    /**
     * @dev Tries to returns the value associated with `key`.  O(1).
     * Does not revert if `key` is not in the map.
     *
     * _Available since v3.4._
     */
    function tryGet(UintToAddressMap storage map, uint256 key) internal view returns (bool, address) {
        (bool success, bytes32 value) = tryGet(map._inner, bytes32(key));
        return (success, address(uint160(uint256(value))));
    }

    /**
     * @dev Returns the value associated with `key`.  O(1).
     *
     * Requirements:
     *
     * - `key` must be in the map.
     */
    function get(UintToAddressMap storage map, uint256 key) internal view returns (address) {
        return address(uint160(uint256(get(map._inner, bytes32(key)))));
    }

    /**
     * @dev Same as {get}, with a custom error message when `key` is not in the map.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryGet}.
     */
    function get(
        UintToAddressMap storage map,
        uint256 key,
        string memory errorMessage
    ) internal view returns (address) {
        return address(uint160(uint256(get(map._inner, bytes32(key), errorMessage))));
    }

    // AddressToUintMap

    struct AddressToUintMap {
        Bytes32ToBytes32Map _inner;
    }

    /**
     * @dev Adds a key-value pair to a map, or updates the value for an existing
     * key. O(1).
     *
     * Returns true if the key was added to the map, that is if it was not
     * already present.
     */
    function set(
        AddressToUintMap storage map,
        address key,
        uint256 value
    ) internal returns (bool) {
        return set(map._inner, bytes32(uint256(uint160(key))), bytes32(value));
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the key was removed from the map, that is if it was present.
     */
    function remove(AddressToUintMap storage map, address key) internal returns (bool) {
        return remove(map._inner, bytes32(uint256(uint160(key))));
    }

    /**
     * @dev Returns true if the key is in the map. O(1).
     */
    function contains(AddressToUintMap storage map, address key) internal view returns (bool) {
        return contains(map._inner, bytes32(uint256(uint160(key))));
    }

    /**
     * @dev Returns the number of elements in the map. O(1).
     */
    function length(AddressToUintMap storage map) internal view returns (uint256) {
        return length(map._inner);
    }

    /**
     * @dev Returns the element stored at position `index` in the set. O(1).
     * Note that there are no guarantees on the ordering of values inside the
     * array, and it may change when more values are added or removed.
     *
     * Requirements:
     *
     * - `index` must be strictly less than {length}.
     */
    function at(AddressToUintMap storage map, uint256 index) internal view returns (address, uint256) {
        (bytes32 key, bytes32 value) = at(map._inner, index);
        return (address(uint160(uint256(key))), uint256(value));
    }

    /**
     * @dev Tries to returns the value associated with `key`.  O(1).
     * Does not revert if `key` is not in the map.
     */
    function tryGet(AddressToUintMap storage map, address key) internal view returns (bool, uint256) {
        (bool success, bytes32 value) = tryGet(map._inner, bytes32(uint256(uint160(key))));
        return (success, uint256(value));
    }

    /**
     * @dev Returns the value associated with `key`.  O(1).
     *
     * Requirements:
     *
     * - `key` must be in the map.
     */
    function get(AddressToUintMap storage map, address key) internal view returns (uint256) {
        return uint256(get(map._inner, bytes32(uint256(uint160(key)))));
    }

    /**
     * @dev Same as {get}, with a custom error message when `key` is not in the map.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryGet}.
     */
    function get(
        AddressToUintMap storage map,
        address key,
        string memory errorMessage
    ) internal view returns (uint256) {
        return uint256(get(map._inner, bytes32(uint256(uint160(key))), errorMessage));
    }

    // Bytes32ToUintMap

    struct Bytes32ToUintMap {
        Bytes32ToBytes32Map _inner;
    }

    /**
     * @dev Adds a key-value pair to a map, or updates the value for an existing
     * key. O(1).
     *
     * Returns true if the key was added to the map, that is if it was not
     * already present.
     */
    function set(
        Bytes32ToUintMap storage map,
        bytes32 key,
        uint256 value
    ) internal returns (bool) {
        return set(map._inner, key, bytes32(value));
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the key was removed from the map, that is if it was present.
     */
    function remove(Bytes32ToUintMap storage map, bytes32 key) internal returns (bool) {
        return remove(map._inner, key);
    }

    /**
     * @dev Returns true if the key is in the map. O(1).
     */
    function contains(Bytes32ToUintMap storage map, bytes32 key) internal view returns (bool) {
        return contains(map._inner, key);
    }

    /**
     * @dev Returns the number of elements in the map. O(1).
     */
    function length(Bytes32ToUintMap storage map) internal view returns (uint256) {
        return length(map._inner);
    }

    /**
     * @dev Returns the element stored at position `index` in the set. O(1).
     * Note that there are no guarantees on the ordering of values inside the
     * array, and it may change when more values are added or removed.
     *
     * Requirements:
     *
     * - `index` must be strictly less than {length}.
     */
    function at(Bytes32ToUintMap storage map, uint256 index) internal view returns (bytes32, uint256) {
        (bytes32 key, bytes32 value) = at(map._inner, index);
        return (key, uint256(value));
    }

    /**
     * @dev Tries to returns the value associated with `key`.  O(1).
     * Does not revert if `key` is not in the map.
     */
    function tryGet(Bytes32ToUintMap storage map, bytes32 key) internal view returns (bool, uint256) {
        (bool success, bytes32 value) = tryGet(map._inner, key);
        return (success, uint256(value));
    }

    /**
     * @dev Returns the value associated with `key`.  O(1).
     *
     * Requirements:
     *
     * - `key` must be in the map.
     */
    function get(Bytes32ToUintMap storage map, bytes32 key) internal view returns (uint256) {
        return uint256(get(map._inner, key));
    }

    /**
     * @dev Same as {get}, with a custom error message when `key` is not in the map.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryGet}.
     */
    function get(
        Bytes32ToUintMap storage map,
        bytes32 key,
        string memory errorMessage
    ) internal view returns (uint256) {
        return uint256(get(map._inner, key, errorMessage));
    }
}
// File: src/v0.8/vendor/openzeppelin-solidity/v4.7.3/contracts/utils/structs/EnumerableSet.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (utils/structs/EnumerableSet.sol)
// This file was procedurally generated from scripts/generate/templates/EnumerableSet.js.

pragma solidity ^0.8.0;

/**
 * @dev Library for managing
 * https://en.wikipedia.org/wiki/Set_(abstract_data_type)[sets] of primitive
 * types.
 *
 * Sets have the following properties:
 *
 * - Elements are added, removed, and checked for existence in constant time
 * (O(1)).
 * - Elements are enumerated in O(n). No guarantees are made on the ordering.
 *
 * ```
 * contract Example {
 *     // Add the library methods
 *     using EnumerableSet for EnumerableSet.AddressSet;
 *
 *     // Declare a set state variable
 *     EnumerableSet.AddressSet private mySet;
 * }
 * ```
 *
 * As of v3.3.0, sets of type `bytes32` (`Bytes32Set`), `address` (`AddressSet`)
 * and `uint256` (`UintSet`) are supported.
 *
 * [WARNING]
 * ====
 *  Trying to delete such a structure from storage will likely result in data corruption, rendering the structure unusable.
 *  See https://github.com/ethereum/solidity/pull/11843[ethereum/solidity#11843] for more info.
 *
 *  In order to clean an EnumerableSet, you can either remove all elements one by one or create a fresh instance using an array of EnumerableSet.
 * ====
 */
library EnumerableSet {
    // To implement this library for multiple types with as little code
    // repetition as possible, we write it in terms of a generic Set type with
    // bytes32 values.
    // The Set implementation uses private functions, and user-facing
    // implementations (such as AddressSet) are just wrappers around the
    // underlying Set.
    // This means that we can only create new EnumerableSets for types that fit
    // in bytes32.

    struct Set {
        // Storage of set values
        bytes32[] _values;
        // Position of the value in the `values` array, plus 1 because index 0
        // means a value is not in the set.
        mapping(bytes32 => uint256) _indexes;
    }

    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function _add(Set storage set, bytes32 value) private returns (bool) {
        if (!_contains(set, value)) {
            set._values.push(value);
            // The value is stored at length-1, but we add 1 to all indexes
            // and use 0 as a sentinel value
            set._indexes[value] = set._values.length;
            return true;
        } else {
            return false;
        }
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function _remove(Set storage set, bytes32 value) private returns (bool) {
        // We read and store the value's index to prevent multiple reads from the same storage slot
        uint256 valueIndex = set._indexes[value];

        if (valueIndex != 0) {
            // Equivalent to contains(set, value)
            // To delete an element from the _values array in O(1), we swap the element to delete with the last one in
            // the array, and then remove the last element (sometimes called as 'swap and pop').
            // This modifies the order of the array, as noted in {at}.

            uint256 toDeleteIndex = valueIndex - 1;
            uint256 lastIndex = set._values.length - 1;

            if (lastIndex != toDeleteIndex) {
                bytes32 lastValue = set._values[lastIndex];

                // Move the last value to the index where the value to delete is
                set._values[toDeleteIndex] = lastValue;
                // Update the index for the moved value
                set._indexes[lastValue] = valueIndex; // Replace lastValue's index to valueIndex
            }

            // Delete the slot where the moved value was stored
            set._values.pop();

            // Delete the index for the deleted slot
            delete set._indexes[value];

            return true;
        } else {
            return false;
        }
    }

    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function _contains(Set storage set, bytes32 value) private view returns (bool) {
        return set._indexes[value] != 0;
    }

    /**
     * @dev Returns the number of values on the set. O(1).
     */
    function _length(Set storage set) private view returns (uint256) {
        return set._values.length;
    }

    /**
     * @dev Returns the value stored at position `index` in the set. O(1).
     *
     * Note that there are no guarantees on the ordering of values inside the
     * array, and it may change when more values are added or removed.
     *
     * Requirements:
     *
     * - `index` must be strictly less than {length}.
     */
    function _at(Set storage set, uint256 index) private view returns (bytes32) {
        return set._values[index];
    }

    /**
     * @dev Return the entire set in an array
     *
     * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
     * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
     * this function has an unbounded cost, and using it as part of a state-changing function may render the function
     * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
     */
    function _values(Set storage set) private view returns (bytes32[] memory) {
        return set._values;
    }

    // Bytes32Set

    struct Bytes32Set {
        Set _inner;
    }

    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(Bytes32Set storage set, bytes32 value) internal returns (bool) {
        return _add(set._inner, value);
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(Bytes32Set storage set, bytes32 value) internal returns (bool) {
        return _remove(set._inner, value);
    }

    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(Bytes32Set storage set, bytes32 value) internal view returns (bool) {
        return _contains(set._inner, value);
    }

    /**
     * @dev Returns the number of values in the set. O(1).
     */
    function length(Bytes32Set storage set) internal view returns (uint256) {
        return _length(set._inner);
    }

    /**
     * @dev Returns the value stored at position `index` in the set. O(1).
     *
     * Note that there are no guarantees on the ordering of values inside the
     * array, and it may change when more values are added or removed.
     *
     * Requirements:
     *
     * - `index` must be strictly less than {length}.
     */
    function at(Bytes32Set storage set, uint256 index) internal view returns (bytes32) {
        return _at(set._inner, index);
    }

    /**
     * @dev Return the entire set in an array
     *
     * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
     * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
     * this function has an unbounded cost, and using it as part of a state-changing function may render the function
     * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
     */
    function values(Bytes32Set storage set) internal view returns (bytes32[] memory) {
        bytes32[] memory store = _values(set._inner);
        bytes32[] memory result;

        /// @solidity memory-safe-assembly
        assembly {
            result := store
        }

        return result;
    }

    // AddressSet

    struct AddressSet {
        Set _inner;
    }

    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(AddressSet storage set, address value) internal returns (bool) {
        return _add(set._inner, bytes32(uint256(uint160(value))));
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(AddressSet storage set, address value) internal returns (bool) {
        return _remove(set._inner, bytes32(uint256(uint160(value))));
    }

    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(AddressSet storage set, address value) internal view returns (bool) {
        return _contains(set._inner, bytes32(uint256(uint160(value))));
    }

    /**
     * @dev Returns the number of values in the set. O(1).
     */
    function length(AddressSet storage set) internal view returns (uint256) {
        return _length(set._inner);
    }

    /**
     * @dev Returns the value stored at position `index` in the set. O(1).
     *
     * Note that there are no guarantees on the ordering of values inside the
     * array, and it may change when more values are added or removed.
     *
     * Requirements:
     *
     * - `index` must be strictly less than {length}.
     */
    function at(AddressSet storage set, uint256 index) internal view returns (address) {
        return address(uint160(uint256(_at(set._inner, index))));
    }

    /**
     * @dev Return the entire set in an array
     *
     * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
     * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
     * this function has an unbounded cost, and using it as part of a state-changing function may render the function
     * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
     */
    function values(AddressSet storage set) internal view returns (address[] memory) {
        bytes32[] memory store = _values(set._inner);
        address[] memory result;

        /// @solidity memory-safe-assembly
        assembly {
            result := store
        }

        return result;
    }

    // UintSet

    struct UintSet {
        Set _inner;
    }

    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(UintSet storage set, uint256 value) internal returns (bool) {
        return _add(set._inner, bytes32(value));
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(UintSet storage set, uint256 value) internal returns (bool) {
        return _remove(set._inner, bytes32(value));
    }

    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(UintSet storage set, uint256 value) internal view returns (bool) {
        return _contains(set._inner, bytes32(value));
    }

    /**
     * @dev Returns the number of values in the set. O(1).
     */
    function length(UintSet storage set) internal view returns (uint256) {
        return _length(set._inner);
    }

    /**
     * @dev Returns the value stored at position `index` in the set. O(1).
     *
     * Note that there are no guarantees on the ordering of values inside the
     * array, and it may change when more values are added or removed.
     *
     * Requirements:
     *
     * - `index` must be strictly less than {length}.
     */
    function at(UintSet storage set, uint256 index) internal view returns (uint256) {
        return uint256(_at(set._inner, index));
    }

    /**
     * @dev Return the entire set in an array
     *
     * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
     * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
     * this function has an unbounded cost, and using it as part of a state-changing function may render the function
     * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
     */
    function values(UintSet storage set) internal view returns (uint256[] memory) {
        bytes32[] memory store = _values(set._inner);
        uint256[] memory result;

        /// @solidity memory-safe-assembly
        assembly {
            result := store
        }

        return result;
    }
}