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

library AddrArrayLib {
    using AddrArrayLib for Addresses;

    struct Addresses {
      address[]  _items;
    }

    /**
     * @notice push an address to the array
     * @dev if the address already exists, it will not be added again
     * @param self Storage array containing address type variables
     * @param element the element to add in the array
     */
    function pushAddress(Addresses storage self, address element) internal {
      if (!exists(self, element)) {
        self._items.push(element);
      }
    }

    /**
     * @notice remove an address from the array
     * @dev finds the element, swaps it with the last element, and then deletes it;
     *      returns a boolean whether the element was found and deleted
     * @param self Storage array containing address type variables
     * @param element the element to remove from the array
     */
    function removeAddress(Addresses storage self, address element) internal {
        for (uint i = 0; i < self.size(); i++) {
            if (self._items[i] == element) {
                self._items[i] = self._items[self.size() - 1];
                self._items.pop();
            }
        }
    }

    /**
     * @notice get the address at a specific index from array
     * @dev revert if the index is out of bounds
     * @param self Storage array containing address type variables
     * @param index the index in the array
     */
    function getAddressAtIndex(Addresses memory self, uint256 index) internal view returns (address) {
        require(index < size(self), "the index is out of bounds");
        return self._items[index];
    }

    /**
     * @notice get the size of the array
     * @param self Storage array containing address type variables
     */
    function size(Addresses memory self) internal view returns (uint256) {
      return self._items.length;
    }

    /**
     * @notice check if an element exist in the array
     * @param self Storage array containing address type variables
     * @param element the element to check if it exists in the array
     */
    function exists(Addresses memory self, address element) internal view returns (bool) {
        for (uint i = 0; i < self.size(); i++) {
            if (self._items[i] == element) {
                return true;
            }
        }
        return false;
    }

    /**
     * @notice get the array
     * @param self Storage array containing address type variables
     */
    function getAllAddresses(Addresses memory self) internal view returns(address[] memory) {
        return self._items;
    }

}

// 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;
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (token/ERC20/ERC20.sol)

pragma solidity ^0.8.0;

import "./IERC20.sol";
import "./extensions/IERC20Metadata.sol";
import "../../utils/Context.sol";

/**
 * @dev Implementation of the {IERC20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 * For a generic mechanism see {ERC20PresetMinterPauser}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * We have followed general OpenZeppelin Contracts guidelines: functions revert
 * instead returning `false` on failure. This behavior is nonetheless
 * conventional and does not conflict with the expectations of ERC20
 * applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 *
 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
 * functions have been added to mitigate the well-known issues around setting
 * allowances. See {IERC20-approve}.
 */
contract ERC20 is Context, IERC20, IERC20Metadata {
    mapping(address => uint256) private _balances;

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

    uint256 private _totalSupply;

    string private _name;
    string private _symbol;

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

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

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

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

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

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

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

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

    /**
     * @dev See {IERC20-approve}.
     *
     * NOTE: If `amount` is the maximum `uint256`, the allowance is not updated on
     * `transferFrom`. This is semantically equivalent to an infinite approval.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function approve(address spender, uint256 amount) public virtual override returns (bool) {
        address owner = _msgSender();
        _approve(owner, spender, amount);
        return true;
    }

    /**
     * @dev See {IERC20-transferFrom}.
     *
     * Emits an {Approval} event indicating the updated allowance. This is not
     * required by the EIP. See the note at the beginning of {ERC20}.
     *
     * NOTE: Does not update the allowance if the current allowance
     * is the maximum `uint256`.
     *
     * Requirements:
     *
     * - `from` and `to` cannot be the zero address.
     * - `from` must have a balance of at least `amount`.
     * - the caller must have allowance for ``from``'s tokens of at least
     * `amount`.
     */
    function transferFrom(
        address from,
        address to,
        uint256 amount
    ) public virtual override returns (bool) {
        address spender = _msgSender();
        _spendAllowance(from, spender, amount);
        _transfer(from, to, amount);
        return true;
    }

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

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

        return true;
    }

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

        _beforeTokenTransfer(from, to, amount);

        uint256 fromBalance = _balances[from];
        require(fromBalance >= amount, "ERC20: transfer amount exceeds balance");
        unchecked {
            _balances[from] = fromBalance - amount;
        }
        _balances[to] += amount;

        emit Transfer(from, to, amount);

        _afterTokenTransfer(from, to, amount);
    }

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

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

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

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

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

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

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

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

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

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

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

    /**
     * @dev Spend `amount` form the allowance of `owner` toward `spender`.
     *
     * Does not update the allowance amount in case of infinite allowance.
     * Revert if not enough allowance is available.
     *
     * Might emit an {Approval} event.
     */
    function _spendAllowance(
        address owner,
        address spender,
        uint256 amount
    ) internal virtual {
        uint256 currentAllowance = allowance(owner, spender);
        if (currentAllowance != type(uint256).max) {
            require(currentAllowance >= amount, "ERC20: insufficient allowance");
            unchecked {
                _approve(owner, spender, currentAllowance - amount);
            }
        }
    }

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

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

/// SPDX-License-Identifier: GPL-3.0-or-later
pragma solidity ^0.8.0;

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

import "../library/AddArrayLib.sol";

import "../interfaces/ITradeExecutor.sol";
import "../interfaces/IHauler.sol";


contract Hauler is IHauler, ERC20 {

    using AddrArrayLib for AddrArrayLib.Addresses;

    // TODO Define this arbitrary limit
    uint constant BLOCK_LIMIT = 50;
    uint constant DUST_LIMIT = 10**6;

    AddrArrayLib.Addresses tradeExecutorsList;

    address public immutable override wantToken;
    uint8 private immutable tokenDecimals;
    bool public batcherOnlyDeposit;

    address public override keeper;
    address public override governance;
    address public batcher;
    address pendingGovernance;
    


    constructor(string memory _name, string memory _symbol, uint8 _decimals, address _wantToken, address _keeper, address _governance) ERC20(_name, _symbol) {
        tokenDecimals = _decimals;
        wantToken = _wantToken;
        keeper = _keeper;
        governance = _governance;
    }

    function decimals() public view override returns (uint8) {
        return tokenDecimals;
    }


    function deposit(uint amountIn, address receiver) public onlyBatcher override returns (uint256 shares) {
        require(amountIn > 0);
        require(receiver != address(0));

        if (totalSupply() > 0) {
            shares = totalSupply() * amountIn / totalHaulerFunds();
        } else {
            shares = amountIn;
        }

        IERC20(wantToken).transferFrom(receiver, address(this), amountIn);
        _mint(receiver, shares);
    }

    function withdraw(uint sharesIn, address receiver) public override returns (uint256 amountOut) {
        require(sharesIn > 0);
        require(receiver != address(0));

        amountOut = sharesIn * totalHaulerFunds() / totalSupply();
        _burn(receiver, sharesIn);
        IERC20(wantToken).transfer(receiver, amountOut);
    }



    function totalHaulerFunds() public view returns (uint) {
        return IERC20(wantToken).balanceOf(address(this)) + totalExecutorFunds();
    }

    function depositIntoExecutor(address _executor, uint _amount) public isActiveExecutor(_executor) onlyKeeper {
        require(_amount > 0);
        IERC20(wantToken).transfer(_executor, _amount);
    }

    function withdrawFromExecutor(address _executor, uint _amount) public isActiveExecutor(_executor) onlyKeeper {
        require(_amount > 0);
        IERC20(wantToken).transferFrom(_executor, address(this), _amount);
    }


    function totalExecutors() public view returns (uint) {
        return tradeExecutorsList.size();
    }

    function executorByIndex(uint _index) public view returns (address) {
        require(_index < totalExecutors(), 'Index out of bounds');
        return tradeExecutorsList.getAddressAtIndex(_index);
    }

    function totalExecutorFunds() public view returns (uint) {
        uint totalFunds = 0;
        for (uint i = 0; i < totalExecutors(); i++) {
            address executor = executorByIndex(i);
            (uint executorFunds, uint blockUpdated) = ITradeExecutor(executor).totalFunds();
            require (block.number <= blockUpdated + BLOCK_LIMIT, 'Executor funds are not up to date');
            totalFunds += executorFunds;

        }
        return totalFunds;
    }


    /// EXECUTOR MANAGEMENT ///
    function addExecutor(address _tradeExecutor) public isValidAddress(_tradeExecutor) onlyKeeper {
        tradeExecutorsList.pushAddress(_tradeExecutor);
    }

    function removeExecutor(address _tradeExecutor) public isValidAddress(_tradeExecutor) onlyKeeper {
        (uint executorFunds, uint blockUpdated) = ITradeExecutor(_tradeExecutor).totalFunds();
        require (block.number <= blockUpdated + BLOCK_LIMIT, 'Executor funds are not up to date');
        require (executorFunds < DUST_LIMIT, 'Executor not empty');
        tradeExecutorsList.removeAddress(_tradeExecutor);
    }

    function setBatcher(address _batcher) public onlyGovernance {
        batcher = _batcher;
    }

    function setBatcherOnlyDeposit(bool _batcherOnlyDeposit) public onlyGovernance {
        batcherOnlyDeposit = _batcherOnlyDeposit;
    }

    function setGovernance(address _governance) public onlyGovernance{
        pendingGovernance = _governance;
    }

    function acceptGovernance() public {
        require(msg.sender == pendingGovernance);
        governance = pendingGovernance;
    }

    function setKeeper(address _keeper) public onlyGovernance {
        keeper = _keeper;
    }

    modifier onlyGovernance {
        require(msg.sender == governance, "Only governance call");
        _;
    }

    modifier onlyKeeper {
        require(msg.sender == keeper, "Only keeper call");
        _;
    }

    modifier onlyBatcher {
        if (batcherOnlyDeposit) {
            require(msg.sender == batcher, "Only batcher call");
        }
        _;
    }

    modifier isValidAddress(address _tradeExecutor) {
        require(_tradeExecutor!= address(0), 'Invalid address');
        _;
    }

    modifier isActiveExecutor(address _tradeExecutor) {
        require(tradeExecutorsList.exists(_tradeExecutor), "Executor is not active or doesnt exist");
        _;
    }

    

}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (token/ERC20/IERC20.sol)

pragma solidity ^0.8.0;

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

    /**
     * @dev Returns the 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);

    /**
     * @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);
}

// 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);
}

/// SPDX-License-Identifier: GPL-3.0-or-later
pragma solidity ^0.8.0;

interface IHauler {
  function keeper() external view returns (address);

  function governance() external view returns (address);

  function wantToken() external view returns (address);

  function deposit(uint256 amountIn, address receiver)
    external
    returns (uint256 shares);

  function withdraw(uint256 sharesIn, address receiver)
    external
    returns (uint256 amountOut);
}

//SPDX-License-Identifier: GPL-3.0-only
pragma solidity ^0.8.0;

interface ITradeExecutor {

    struct ActionStatus {
        bool inProcess;
        address from;
    }

    function depositStatus() external returns (bool, address);
    function withdrawalStatus() external returns (bool, address);

    function initiateDeposit(bytes calldata _data) external;

    function confirmDeposit() external;

    function initateWithdraw(bytes calldata _data) external;

    function confirmWithdraw() external;

    function totalFunds() view external returns(uint256 posValue, uint256 lastUpdatedBlock);

}

{
  "compilationTarget": {
    "contracts/Hauler.sol": "Hauler"
  },
  "evmVersion": "istanbul",
  "libraries": {},
  "metadata": {
    "bytecodeHash": "ipfs"
  },
  "optimizer": {
    "enabled": true,
    "runs": 100
  },
  "remappings": []
}