// based on ERC20 implementation of openzeppelin-solidity: https://github.com/OpenZeppelin/openzeppelin-contracts/blob/7552af95e4ec6fccd64a95b206f59a1b4ff91517/contracts/token/ERC20/ERC20.sol
pragma solidity ^0.5.12;

import { AutoRefactorCoinageI } from "AutoRefactorCoinageI.sol";
import { SafeMath } from "openzeppelin-solidity/SafeMath.sol";
import { Context } from "openzeppelin-solidity/Context.sol";
import { Ownable } from "openzeppelin-solidity/Ownable.sol";
import { IERC20 } from "openzeppelin-solidity/IERC20.sol";
import { ERC20Detailed } from "openzeppelin-solidity/ERC20Detailed.sol";
import { ERC20Mintable } from "openzeppelin-solidity/ERC20Mintable.sol";
import { ERC20Burnable } from "openzeppelin-solidity/ERC20Burnable.sol";

import { DSMath } from "DSMath.sol";


/**
 * @dev Implementation of coin age token based on ERC20 of openzeppelin-solidity
 *
 * AutoRefactorCoinage stores `_totalSupply` and `_balances` as RAY BASED value,
 * `_allowances` as RAY FACTORED value.
 *
 * This takes public function (including _approve) parameters as RAY FACTORED value
 * and internal function (including approve) parameters as RAY BASED value, and emits event in RAY FACTORED value.
 *
 * `RAY BASED` = `RAY FACTORED`  / factor
 *
 *  factor increases exponentially for each block mined.
 */
contract AutoRefactorCoinage is Context, IERC20, DSMath, Ownable, ERC20Detailed, ERC20Mintable, ERC20Burnable {
  using SafeMath for uint256;

  struct Balance {
    uint256 balance;
    uint256 refactoredCount;
    uint256 remain;
  }

  uint256 public REFACTOR_BOUNDARY = 10 ** 28;
  uint256 public REFACTOR_DIVIDER = 2;

  uint256 public refactorCount;

  mapping (address => Balance) public balances;

  Balance public _totalSupply;

  uint256 public _factor;

  bool internal _transfersEnabled;

  event FactorSet(uint256 previous, uint256 current, uint256 shiftCount);

  constructor (
    string memory name,
    string memory symbol,
    uint256 factor
  )
    public
    ERC20Detailed(name, symbol, 27)
  {
    _factor = factor;
    //_factorIncrement = factorIncrement;
    //_lastBlock = block.number;
    //_transfersEnabled = transfersEnabled;
  }

  function factor() public view returns (uint256) {
    uint256 result = _factor;
    for (uint256 i = 0; i < refactorCount; i++) {
      result = result.mul(REFACTOR_DIVIDER);
    }
    return result;
  }

  /**
    * @dev See {IERC20-totalSupply}.
    */
  function totalSupply() public view returns (uint256) {
    return _applyFactor(_totalSupply.balance, _totalSupply.refactoredCount).add(_totalSupply.remain);
  }


  /**
    * @dev See {IERC20-balanceOf}.
    */
  function balanceOf(address account) public view returns (uint256) {
    Balance storage b = balances[account];

    return _applyFactor(b.balance, b.refactoredCount).add(b.remain);
  }

  /** @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
    *
    * - `to` cannot be the zero address.
    */
  function _mint(address account, uint256 amount) internal {
    require(account != address(0), "AutoRefactorCoinage: mint to the zero address");
    Balance storage b = balances[account];

    uint256 currentBalance = balanceOf(account);
    uint256 newBalance = currentBalance.add(amount);

    uint256 rbAmount = _toRAYBased(newBalance);
    b.balance = rbAmount;
    b.refactoredCount = refactorCount;

    addTotalSupply(amount);
    emit Transfer(address(0), account, _toRAYFactored(rbAmount));
  }

    /**
    * @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 {
    require(account != address(0), "AutoRefactorCoinage: burn from the zero address");
    Balance storage b = balances[account];

    uint256 currentBalance = balanceOf(account);
    uint256 newBalance = currentBalance.sub(amount);

    uint256 rbAmount = _toRAYBased(newBalance);
    b.balance = rbAmount;
    b.refactoredCount = refactorCount;

    subTotalSupply(amount);
    emit Transfer(account, address(0), _toRAYFactored(rbAmount));
  }

  function _burnFrom(address account, uint256 amount) internal {
    _burn(account, amount);
  }

  // helpers

  /**
   * @param v the value to be factored
   */
  function _applyFactor(uint256 v, uint256 refactoredCount) internal view returns (uint256) {
    if (v == 0) {
      return 0;
    }

    v = rmul2(v, _factor);

    for (uint256 i = refactoredCount; i < refactorCount; i++) {
      v = v.mul(REFACTOR_DIVIDER);
    }

    return v;
  }

  /**
   * @dev Calculate RAY BASED from RAY FACTORED
   */
  function _toRAYBased(uint256 rf) internal view returns (uint256 rb) {
    return rdiv2(rf, _factor);
  }

  /**
   * @dev Calculate RAY FACTORED from RAY BASED
   */
  function _toRAYFactored(uint256 rb) internal view returns (uint256 rf) {
    return rmul2(rb, _factor);
  }


  // new

  function setFactor(uint256 factor) external onlyOwner returns (bool) {
    uint256 previous = _factor;

    uint256 count = 0;
    uint256 f = factor;
    for (; f >= REFACTOR_BOUNDARY; f = f.div(REFACTOR_DIVIDER)) {
      count = count.add(1);
    }

    refactorCount = count;
    _factor = f;
    emit FactorSet(previous, f, count);
  }

  function addTotalSupply(uint256 amount) internal {
    uint256 currentSupply = _applyFactor(_totalSupply.balance, _totalSupply.refactoredCount);
    uint256 newSupply = currentSupply.add(amount);

    uint256 rbAmount = _toRAYBased(newSupply);
    _totalSupply.balance = rbAmount;
    _totalSupply.refactoredCount = refactorCount;
  }

  function subTotalSupply(uint256 amount) internal {
    uint256 currentSupply = _applyFactor(_totalSupply.balance, _totalSupply.refactoredCount);
    uint256 newSupply = currentSupply.sub(amount);

    uint256 rbAmount = _toRAYBased(newSupply);
    _totalSupply.balance = rbAmount;
    _totalSupply.refactoredCount = refactorCount;
  }

  // unsupported functions

  function transfer(address recipient, uint256 amount) public returns (bool) {
    revert();
  }

  function allowance(address owner, address spender) public view returns (uint256) {
    return 0;
  }

  function approve(address spender, uint256 amount) public returns (bool) {
    revert();
  }

  function transferFrom(address sender, address recipient, uint256 amount) public returns (bool) {
    revert();
  }
}

pragma solidity ^0.5.12;

interface AutoRefactorCoinageI {
  function factor() external view returns (uint256);
  function setFactor(uint256 factor) external returns (bool);
  function burn(uint256 amount) external;
  function burnFrom(address account, uint256 amount) external;
  function mint(address account, uint256 amount) external returns (bool);
  function totalSupply() external view returns (uint256);
  function balanceOf(address account) external view returns (uint256);
  function addMinter(address account) external;
  function renounceMinter() external;
  function transferOwnership(address newOwner) external;
}

pragma solidity ^0.5.0;

/*
 * @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 GSN 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.
 */
contract Context {
    // Empty internal constructor, to prevent people from mistakenly deploying
    // an instance of this contract, which should be used via inheritance.
    constructor () internal { }
    // solhint-disable-previous-line no-empty-blocks

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

    function _msgData() internal view returns (bytes memory) {
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
        return msg.data;
    }
}

// https://github.com/dapphub/ds-math/blob/de45767/src/math.sol
/// math.sol -- mixin for inline numerical wizardry

// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

pragma solidity >0.4.13;

contract DSMath {
  function add(uint x, uint y) internal pure returns (uint z) {
    require((z = x + y) >= x, "ds-math-add-overflow");
  }
  function sub(uint x, uint y) internal pure returns (uint z) {
    require((z = x - y) <= x, "ds-math-sub-underflow");
  }
  function mul(uint x, uint y) internal pure returns (uint z) {
    require(y == 0 || (z = x * y) / y == x, "ds-math-mul-overflow");
  }

  function min(uint x, uint y) internal pure returns (uint z) {
    return x <= y ? x : y;
  }
  function max(uint x, uint y) internal pure returns (uint z) {
    return x >= y ? x : y;
  }
  function imin(int x, int y) internal pure returns (int z) {
    return x <= y ? x : y;
  }
  function imax(int x, int y) internal pure returns (int z) {
    return x >= y ? x : y;
  }

  uint constant WAD = 10 ** 18;
  uint constant RAY = 10 ** 27;

  function wmul(uint x, uint y) internal pure returns (uint z) {
    z = add(mul(x, y), WAD / 2) / WAD;
  }
  function rmul(uint x, uint y) internal pure returns (uint z) {
    z = add(mul(x, y), RAY / 2) / RAY;
  }
  function wdiv(uint x, uint y) internal pure returns (uint z) {
    z = add(mul(x, WAD), y / 2) / y;
  }
  function rdiv(uint x, uint y) internal pure returns (uint z) {
    z = add(mul(x, RAY), y / 2) / y;
  }

  function wmul2(uint x, uint y) internal pure returns (uint z) {
    z = mul(x, y) / WAD;
  }
  function rmul2(uint x, uint y) internal pure returns (uint z) {
    z = mul(x, y) / RAY;
  }
  function wdiv2(uint x, uint y) internal pure returns (uint z) {
    z = mul(x, WAD) / y;
  }
  function rdiv2(uint x, uint y) internal pure returns (uint z) {
    z = mul(x, RAY) / y;
  }

  // This famous algorithm is called "exponentiation by squaring"
  // and calculates x^n with x as fixed-point and n as regular unsigned.
  //
  // It's O(log n), instead of O(n) for naive repeated multiplication.
  //
  // These facts are why it works:
  //
  //  If n is even, then x^n = (x^2)^(n/2).
  //  If n is odd,  then x^n = x * x^(n-1),
  //   and applying the equation for even x gives
  //  x^n = x * (x^2)^((n-1) / 2).
  //
  //  Also, EVM division is flooring and
  //  floor[(n-1) / 2] = floor[n / 2].
  //
  function wpow(uint x, uint n) internal pure returns (uint z) {
    z = n % 2 != 0 ? x : WAD;

    for (n /= 2; n != 0; n /= 2) {
      x = wmul(x, x);

      if (n % 2 != 0) {
        z = wmul(z, x);
      }
    }
  }

  function rpow(uint x, uint n) internal pure returns (uint z) {
    z = n % 2 != 0 ? x : RAY;

    for (n /= 2; n != 0; n /= 2) {
      x = rmul(x, x);

      if (n % 2 != 0) {
        z = rmul(z, x);
      }
    }
  }
}

pragma solidity ^0.5.0;

import "openzeppelin-solidity/Context.sol";
import "openzeppelin-solidity/IERC20.sol";
import "openzeppelin-solidity/SafeMath.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 {ERC20Mintable}.
 *
 * 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 guidelines: functions revert instead
 * of 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 {
    using SafeMath for uint256;

    mapping (address => uint256) private _balances;

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

    uint256 private _totalSupply;

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

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

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

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

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

    /**
     * @dev See {IERC20-transferFrom}.
     *
     * Emits an {Approval} event indicating the updated allowance. This is not
     * required by the EIP. See the note at the beginning of {ERC20};
     *
     * Requirements:
     * - `sender` and `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     * - the caller must have allowance for `sender`'s tokens of at least
     * `amount`.
     */
    function transferFrom(address sender, address recipient, uint256 amount) public returns (bool) {
        _transfer(sender, recipient, amount);
        _approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, "ERC20: transfer amount exceeds allowance"));
        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 returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].add(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 returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].sub(subtractedValue, "ERC20: decreased allowance below zero"));
        return true;
    }

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

        _balances[sender] = _balances[sender].sub(amount, "ERC20: transfer amount exceeds balance");
        _balances[recipient] = _balances[recipient].add(amount);
        emit Transfer(sender, recipient, amount);
    }

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

        _totalSupply = _totalSupply.add(amount);
        _balances[account] = _balances[account].add(amount);
        emit Transfer(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 {
        require(account != address(0), "ERC20: burn from the zero address");

        _balances[account] = _balances[account].sub(amount, "ERC20: burn amount exceeds balance");
        _totalSupply = _totalSupply.sub(amount);
        emit Transfer(account, address(0), amount);
    }

    /**
     * @dev Sets `amount` as the allowance of `spender` over the `owner`s tokens.
     *
     * This is 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 {
        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 Destroys `amount` tokens from `account`.`amount` is then deducted
     * from the caller's allowance.
     *
     * See {_burn} and {_approve}.
     */
    function _burnFrom(address account, uint256 amount) internal {
        _burn(account, amount);
        _approve(account, _msgSender(), _allowances[account][_msgSender()].sub(amount, "ERC20: burn amount exceeds allowance"));
    }
}

pragma solidity ^0.5.0;

import "openzeppelin-solidity/Context.sol";
import "openzeppelin-solidity/ERC20.sol";

/**
 * @dev Extension of {ERC20} that allows token holders to destroy both their own
 * tokens and those that they have an allowance for, in a way that can be
 * recognized off-chain (via event analysis).
 */
contract ERC20Burnable is Context, ERC20 {
    /**
     * @dev Destroys `amount` tokens from the caller.
     *
     * See {ERC20-_burn}.
     */
    function burn(uint256 amount) public {
        _burn(_msgSender(), amount);
    }

    /**
     * @dev See {ERC20-_burnFrom}.
     */
    function burnFrom(address account, uint256 amount) public {
        _burnFrom(account, amount);
    }
}

pragma solidity ^0.5.0;

import "openzeppelin-solidity/IERC20.sol";

/**
 * @dev Optional functions from the ERC20 standard.
 */
contract ERC20Detailed is IERC20 {
    string private _name;
    string private _symbol;
    uint8 private _decimals;

    /**
     * @dev Sets the values for `name`, `symbol`, and `decimals`. All three of
     * these values are immutable: they can only be set once during
     * construction.
     */
    constructor (string memory name, string memory symbol, uint8 decimals) public {
        _name = name;
        _symbol = symbol;
        _decimals = decimals;
    }

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

    /**
     * @dev Returns the symbol of the token, usually a shorter version of the
     * name.
     */
    function symbol() public view 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.
     *
     * 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 returns (uint8) {
        return _decimals;
    }
}

pragma solidity ^0.5.0;

import "openzeppelin-solidity/ERC20.sol";
import "openzeppelin-solidity/MinterRole.sol";

/**
 * @dev Extension of {ERC20} that adds a set of accounts with the {MinterRole},
 * which have permission to mint (create) new tokens as they see fit.
 *
 * At construction, the deployer of the contract is the only minter.
 */
contract ERC20Mintable is ERC20, MinterRole {
    /**
     * @dev See {ERC20-_mint}.
     *
     * Requirements:
     *
     * - the caller must have the {MinterRole}.
     */
    function mint(address account, uint256 amount) public onlyMinter returns (bool) {
        _mint(account, amount);
        return true;
    }
}

pragma solidity ^0.5.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP. Does not include
 * the optional functions; to access them see {ERC20Detailed}.
 */
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 `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);

    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);

    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
}

pragma solidity ^0.5.0;

import "openzeppelin-solidity/Context.sol";
import "openzeppelin-solidity/Roles.sol";

contract MinterRole is Context {
    using Roles for Roles.Role;

    event MinterAdded(address indexed account);
    event MinterRemoved(address indexed account);

    Roles.Role private _minters;

    constructor () internal {
        _addMinter(_msgSender());
    }

    modifier onlyMinter() {
        require(isMinter(_msgSender()), "MinterRole: caller does not have the Minter role");
        _;
    }

    function isMinter(address account) public view returns (bool) {
        return _minters.has(account);
    }

    function addMinter(address account) public onlyMinter {
        _addMinter(account);
    }

    function renounceMinter() public {
        _removeMinter(_msgSender());
    }

    function _addMinter(address account) internal {
        _minters.add(account);
        emit MinterAdded(account);
    }

    function _removeMinter(address account) internal {
        _minters.remove(account);
        emit MinterRemoved(account);
    }
}

pragma solidity ^0.5.0;

import "openzeppelin-solidity/Context.sol";
/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
contract Ownable is Context {
    address private _owner;

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

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor () internal {
        address msgSender = _msgSender();
        _owner = msgSender;
        emit OwnershipTransferred(address(0), msgSender);
    }

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

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

    /**
     * @dev Returns true if the caller is the current owner.
     */
    function isOwner() public view returns (bool) {
        return _msgSender() == _owner;
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public onlyOwner {
        emit OwnershipTransferred(_owner, address(0));
        _owner = address(0);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public onlyOwner {
        _transferOwnership(newOwner);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     */
    function _transferOwnership(address newOwner) internal {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }
}

pragma solidity ^0.5.0;

/**
 * @title Roles
 * @dev Library for managing addresses assigned to a Role.
 */
library Roles {
    struct Role {
        mapping (address => bool) bearer;
    }

    /**
     * @dev Give an account access to this role.
     */
    function add(Role storage role, address account) internal {
        require(!has(role, account), "Roles: account already has role");
        role.bearer[account] = true;
    }

    /**
     * @dev Remove an account's access to this role.
     */
    function remove(Role storage role, address account) internal {
        require(has(role, account), "Roles: account does not have role");
        role.bearer[account] = false;
    }

    /**
     * @dev Check if an account has this role.
     * @return bool
     */
    function has(Role storage role, address account) internal view returns (bool) {
        require(account != address(0), "Roles: account is the zero address");
        return role.bearer[account];
    }
}

pragma solidity ^0.5.0;

/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when an
 * operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");

        return c;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        return sub(a, b, "SafeMath: subtraction overflow");
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     * - Subtraction cannot overflow.
     *
     * _Available since v2.4.0._
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        uint256 c = a - b;

        return c;
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
        if (a == 0) {
            return 0;
        }

        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");

        return c;
    }

    /**
     * @dev Returns the integer division of two unsigned integers. Reverts on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return div(a, b, "SafeMath: division by zero");
    }

    /**
     * @dev Returns the integer division of two unsigned integers. Reverts with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     * - The divisor cannot be zero.
     *
     * _Available since v2.4.0._
     */
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        // Solidity only automatically asserts when dividing by 0
        require(b > 0, errorMessage);
        uint256 c = a / b;
        // assert(a == b * c + a % b); // There is no case in which this doesn't hold

        return c;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * Reverts when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        return mod(a, b, "SafeMath: modulo by zero");
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * Reverts with custom message when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     * - The divisor cannot be zero.
     *
     * _Available since v2.4.0._
     */
    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b != 0, errorMessage);
        return a % b;
    }
}

{
  "compilationTarget": {
    "AutoRefactorCoinage.sol": "AutoRefactorCoinage"
  },
  "evmVersion": "istanbul",
  "libraries": {},
  "metadata": {
    "useLiteralContent": true
  },
  "optimizer": {
    "enabled": true,
    "runs": 200
  },
  "remappings": []
}