pragma solidity ^0.4.13;

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(account != address(0));
    require(!has(role, account));

    role.bearer[account] = true;
  }

  /**
   * @dev remove an account's access to this role
   */
  function remove(Role storage role, address account) internal {
    require(account != address(0));
    require(has(role, account));

    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));
    return role.bearer[account];
  }
}

contract MinterRole {
  using Roles for Roles.Role;

  event MinterAdded(address indexed account);
  event MinterRemoved(address indexed account);

  Roles.Role private minters;

  constructor() internal {
    _addMinter(msg.sender);
  }

  modifier onlyMinter() {
    require(isMinter(msg.sender));
    _;
  }

  function isMinter(address account) public view returns (bool) {
    return minters.has(account);
  }

  function addMinter(address account) public onlyMinter {
    _addMinter(account);
  }

  function renounceMinter() public {
    _removeMinter(msg.sender);
  }

  function _addMinter(address account) internal {
    minters.add(account);
    emit MinterAdded(account);
  }

  function _removeMinter(address account) internal {
    minters.remove(account);
    emit MinterRemoved(account);
  }
}

library SafeMath {

  /**
  * @dev Multiplies two numbers, reverts on 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-solidity/pull/522
    if (a == 0) {
      return 0;
    }

    uint256 c = a * b;
    require(c / a == b);

    return c;
  }

  /**
  * @dev Integer division of two numbers truncating the quotient, reverts on division by zero.
  */
  function div(uint256 a, uint256 b) internal pure returns (uint256) {
    require(b > 0); // Solidity only automatically asserts when dividing by 0
    uint256 c = a / b;
    // assert(a == b * c + a % b); // There is no case in which this doesn't hold

    return c;
  }

  /**
  * @dev Subtracts two numbers, reverts on overflow (i.e. if subtrahend is greater than minuend).
  */
  function sub(uint256 a, uint256 b) internal pure returns (uint256) {
    require(b <= a);
    uint256 c = a - b;

    return c;
  }

  /**
  * @dev Adds two numbers, reverts on overflow.
  */
  function add(uint256 a, uint256 b) internal pure returns (uint256) {
    uint256 c = a + b;
    require(c >= a);

    return c;
  }

  /**
  * @dev Divides two numbers and returns the remainder (unsigned integer modulo),
  * reverts when dividing by zero.
  */
  function mod(uint256 a, uint256 b) internal pure returns (uint256) {
    require(b != 0);
    return a % b;
  }
}

interface IERC20 {
  function totalSupply() external view returns (uint256);

  function balanceOf(address who) external view returns (uint256);

  function allowance(address owner, address spender)
    external view returns (uint256);

  function transfer(address to, uint256 value) external returns (bool);

  function approve(address spender, uint256 value)
    external returns (bool);

  function transferFrom(address from, address to, uint256 value)
    external returns (bool);

  event Transfer(
    address indexed from,
    address indexed to,
    uint256 value
  );

  event Approval(
    address indexed owner,
    address indexed spender,
    uint256 value
  );
}

contract ERC20 is IERC20 {
  using SafeMath for uint256;

  mapping (address => uint256) private _balances;

  mapping (address => mapping (address => uint256)) private _allowed;

  uint256 private _totalSupply;

  /**
  * @dev Total number of tokens in existence
  */
  function totalSupply() public view returns (uint256) {
    return _totalSupply;
  }

  /**
  * @dev Gets the balance of the specified address.
  * @param owner The address to query the balance of.
  * @return An uint256 representing the amount owned by the passed address.
  */
  function balanceOf(address owner) public view returns (uint256) {
    return _balances[owner];
  }

  /**
   * @dev Function to check the amount of tokens that an owner allowed to a spender.
   * @param owner address The address which owns the funds.
   * @param spender address The address which will spend the funds.
   * @return A uint256 specifying the amount of tokens still available for the spender.
   */
  function allowance(
    address owner,
    address spender
   )
    public
    view
    returns (uint256)
  {
    return _allowed[owner][spender];
  }

  /**
  * @dev Transfer token for a specified address
  * @param to The address to transfer to.
  * @param value The amount to be transferred.
  */
  function transfer(address to, uint256 value) public returns (bool) {
    _transfer(msg.sender, to, value);
    return true;
  }

  /**
   * @dev Approve the passed address to spend the specified amount of tokens on behalf of msg.sender.
   * 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
   * @param spender The address which will spend the funds.
   * @param value The amount of tokens to be spent.
   */
  function approve(address spender, uint256 value) public returns (bool) {
    require(spender != address(0));

    _allowed[msg.sender][spender] = value;
    emit Approval(msg.sender, spender, value);
    return true;
  }

  /**
   * @dev Transfer tokens from one address to another
   * @param from address The address which you want to send tokens from
   * @param to address The address which you want to transfer to
   * @param value uint256 the amount of tokens to be transferred
   */
  function transferFrom(
    address from,
    address to,
    uint256 value
  )
    public
    returns (bool)
  {
    require(value <= _allowed[from][msg.sender]);

    _allowed[from][msg.sender] = _allowed[from][msg.sender].sub(value);
    _transfer(from, to, value);
    return true;
  }

  /**
   * @dev Increase the amount of tokens that an owner allowed to a spender.
   * approve should be called when allowed_[_spender] == 0. To increment
   * allowed value is better to use this function to avoid 2 calls (and wait until
   * the first transaction is mined)
   * From MonolithDAO Token.sol
   * @param spender The address which will spend the funds.
   * @param addedValue The amount of tokens to increase the allowance by.
   */
  function increaseAllowance(
    address spender,
    uint256 addedValue
  )
    public
    returns (bool)
  {
    require(spender != address(0));

    _allowed[msg.sender][spender] = (
      _allowed[msg.sender][spender].add(addedValue));
    emit Approval(msg.sender, spender, _allowed[msg.sender][spender]);
    return true;
  }

  /**
   * @dev Decrease the amount of tokens that an owner allowed to a spender.
   * approve should be called when allowed_[_spender] == 0. To decrement
   * allowed value is better to use this function to avoid 2 calls (and wait until
   * the first transaction is mined)
   * From MonolithDAO Token.sol
   * @param spender The address which will spend the funds.
   * @param subtractedValue The amount of tokens to decrease the allowance by.
   */
  function decreaseAllowance(
    address spender,
    uint256 subtractedValue
  )
    public
    returns (bool)
  {
    require(spender != address(0));

    _allowed[msg.sender][spender] = (
      _allowed[msg.sender][spender].sub(subtractedValue));
    emit Approval(msg.sender, spender, _allowed[msg.sender][spender]);
    return true;
  }

  /**
  * @dev Transfer token for a specified addresses
  * @param from The address to transfer from.
  * @param to The address to transfer to.
  * @param value The amount to be transferred.
  */
  function _transfer(address from, address to, uint256 value) internal {
    require(value <= _balances[from]);
    require(to != address(0));

    _balances[from] = _balances[from].sub(value);
    _balances[to] = _balances[to].add(value);
    emit Transfer(from, to, value);
  }

  /**
   * @dev Internal function that mints an amount of the token and assigns it to
   * an account. This encapsulates the modification of balances such that the
   * proper events are emitted.
   * @param account The account that will receive the created tokens.
   * @param value The amount that will be created.
   */
  function _mint(address account, uint256 value) internal {
    require(account != 0);
    _totalSupply = _totalSupply.add(value);
    _balances[account] = _balances[account].add(value);
    emit Transfer(address(0), account, value);
  }

  /**
   * @dev Internal function that burns an amount of the token of a given
   * account.
   * @param account The account whose tokens will be burnt.
   * @param value The amount that will be burnt.
   */
  function _burn(address account, uint256 value) internal {
    require(account != 0);
    require(value <= _balances[account]);

    _totalSupply = _totalSupply.sub(value);
    _balances[account] = _balances[account].sub(value);
    emit Transfer(account, address(0), value);
  }

  /**
   * @dev Internal function that burns an amount of the token of a given
   * account, deducting from the sender's allowance for said account. Uses the
   * internal burn function.
   * @param account The account whose tokens will be burnt.
   * @param value The amount that will be burnt.
   */
  function _burnFrom(address account, uint256 value) internal {
    require(value <= _allowed[account][msg.sender]);

    // Should https://github.com/OpenZeppelin/zeppelin-solidity/issues/707 be accepted,
    // this function needs to emit an event with the updated approval.
    _allowed[account][msg.sender] = _allowed[account][msg.sender].sub(
      value);
    _burn(account, value);
  }
}

contract ERC20Mintable is ERC20, MinterRole {
  /**
   * @dev Function to mint tokens
   * @param to The address that will receive the minted tokens.
   * @param value The amount of tokens to mint.
   * @return A boolean that indicates if the operation was successful.
   */
  function mint(
    address to,
    uint256 value
  )
    public
    onlyMinter
    returns (bool)
  {
    _mint(to, value);
    return true;
  }
}

contract RevenueToken is ERC20Mintable {
    using SafeMath for uint256;

    bool public mintingDisabled;

    address[] public holders;

    mapping(address => bool) public holdersMap;

    mapping(address => uint256[]) public balances;

    mapping(address => uint256[]) public balanceBlocks;

    mapping(address => uint256[]) public balanceBlockNumbers;

    event DisableMinting();

    /**
     * @notice Disable further minting
     * @dev This operation can not be undone
     */
    function disableMinting()
    public
    onlyMinter
    {
        mintingDisabled = true;

        emit DisableMinting();
    }

    /**
     * @notice Mint tokens
     * @param to The address that will receive the minted tokens.
     * @param value The amount of tokens to mint.
     * @return A boolean that indicates if the operation was successful.
     */
    function mint(address to, uint256 value)
    public
    onlyMinter
    returns (bool)
    {
        require(!mintingDisabled);

        // Call super's mint, including event emission
        bool minted = super.mint(to, value);

        if (minted) {
            // Adjust balance blocks
            addBalanceBlocks(to);

            // Add to the token holders list
            if (!holdersMap[to]) {
                holdersMap[to] = true;
                holders.push(to);
            }
        }

        return minted;
    }

    /**
     * @notice Transfer token for a specified address
     * @param to The address to transfer to.
     * @param value The amount to be transferred.
     * @return A boolean that indicates if the operation was successful.
     */
    function transfer(address to, uint256 value)
    public
    returns (bool)
    {
        // Call super's transfer, including event emission
        bool transferred = super.transfer(to, value);

        if (transferred) {
            // Adjust balance blocks
            addBalanceBlocks(msg.sender);
            addBalanceBlocks(to);

            // Add to the token holders list
            if (!holdersMap[to]) {
                holdersMap[to] = true;
                holders.push(to);
            }
        }

        return transferred;
    }

    /**
     * @notice Approve the passed address to spend the specified amount of tokens on behalf of msg.sender.
     * @dev Beware that to change the approve amount you first have to reduce the addresses'
     * allowance to zero by calling `approve(spender, 0)` if it is not already 0 to mitigate the race
     * condition described here:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     * @param spender The address which will spend the funds.
     * @param value The amount of tokens to be spent.
     */
    function approve(address spender, uint256 value)
    public
    returns (bool)
    {
        // Prevent the update of non-zero allowance
        require(0 == value || 0 == allowance(msg.sender, spender));

        // Call super's approve, including event emission
        return super.approve(spender, value);
    }

    /**
     * @dev Transfer tokens from one address to another
     * @param from address The address which you want to send tokens from
     * @param to address The address which you want to transfer to
     * @param value uint256 the amount of tokens to be transferred
     * @return A boolean that indicates if the operation was successful.
     */
    function transferFrom(address from, address to, uint256 value)
    public
    returns (bool)
    {
        // Call super's transferFrom, including event emission
        bool transferred = super.transferFrom(from, to, value);

        if (transferred) {
            // Adjust balance blocks
            addBalanceBlocks(from);
            addBalanceBlocks(to);

            // Add to the token holders list
            if (!holdersMap[to]) {
                holdersMap[to] = true;
                holders.push(to);
            }
        }

        return transferred;
    }

    /**
     * @notice Calculate the amount of balance blocks, i.e. the area under the curve (AUC) of
     * balance as function of block number
     * @dev The AUC is used as weight for the share of revenue that a token holder may claim
     * @param account The account address for which calculation is done
     * @param startBlock The start block number considered
     * @param endBlock The end block number considered
     * @return The calculated AUC
     */
    function balanceBlocksIn(address account, uint256 startBlock, uint256 endBlock)
    public
    view
    returns (uint256)
    {
        require(startBlock < endBlock);
        require(account != address(0));

        if (balanceBlockNumbers[account].length == 0 || endBlock < balanceBlockNumbers[account][0])
            return 0;

        uint256 i = 0;
        while (i < balanceBlockNumbers[account].length && balanceBlockNumbers[account][i] < startBlock)
            i++;

        uint256 r;
        if (i >= balanceBlockNumbers[account].length)
            r = balances[account][balanceBlockNumbers[account].length - 1].mul(endBlock.sub(startBlock));

        else {
            uint256 l = (i == 0) ? startBlock : balanceBlockNumbers[account][i - 1];

            uint256 h = balanceBlockNumbers[account][i];
            if (h > endBlock)
                h = endBlock;

            h = h.sub(startBlock);
            r = (h == 0) ? 0 : balanceBlocks[account][i].mul(h).div(balanceBlockNumbers[account][i].sub(l));
            i++;

            while (i < balanceBlockNumbers[account].length && balanceBlockNumbers[account][i] < endBlock) {
                r = r.add(balanceBlocks[account][i]);
                i++;
            }

            if (i >= balanceBlockNumbers[account].length)
                r = r.add(
                    balances[account][balanceBlockNumbers[account].length - 1].mul(
                        endBlock.sub(balanceBlockNumbers[account][balanceBlockNumbers[account].length - 1])
                    )
                );

            else if (balanceBlockNumbers[account][i - 1] < endBlock)
                r = r.add(
                    balanceBlocks[account][i].mul(
                        endBlock.sub(balanceBlockNumbers[account][i - 1])
                    ).div(
                        balanceBlockNumbers[account][i].sub(balanceBlockNumbers[account][i - 1])
                    )
                );
        }

        return r;
    }

    /**
     * @notice Get the count of balance updates for the given account
     * @return The count of balance updates
     */
    function balanceUpdatesCount(address account)
    public
    view
    returns (uint256)
    {
        return balanceBlocks[account].length;
    }

    /**
     * @notice Get the count of holders
     * @return The count of holders
     */
    function holdersCount()
    public
    view
    returns (uint256)
    {
        return holders.length;
    }

    /**
     * @notice Get the subset of holders (optionally with positive balance only) in the given 0 based index range
     * @param low The lower inclusive index
     * @param up The upper inclusive index
     * @param posOnly List only positive balance holders
     * @return The subset of positive balance registered holders in the given range
     */
    function holdersByIndices(uint256 low, uint256 up, bool posOnly)
    public
    view
    returns (address[])
    {
        require(low <= up);

        up = up > holders.length - 1 ? holders.length - 1 : up;

        uint256 length = 0;
        if (posOnly) {
            for (uint256 i = low; i <= up; i++)
                if (0 < balanceOf(holders[i]))
                    length++;
        } else
            length = up - low + 1;

        address[] memory _holders = new address[](length);

        uint256 j = 0;
        for (i = low; i <= up; i++)
            if (!posOnly || 0 < balanceOf(holders[i]))
                _holders[j++] = holders[i];

        return _holders;
    }

    function addBalanceBlocks(address account)
    private
    {
        uint256 length = balanceBlockNumbers[account].length;
        balances[account].push(balanceOf(account));
        if (0 < length)
            balanceBlocks[account].push(
                balances[account][length - 1].mul(
                    block.number.sub(balanceBlockNumbers[account][length - 1])
                )
            );
        else
            balanceBlocks[account].push(0);
        balanceBlockNumbers[account].push(block.number);
    }
}

contract NahmiiToken is RevenueToken {

    string public name = "Nahmii";

    string public symbol = "NII";

    uint8 public constant decimals = 15;

    event SetName(string name);

    event SetSymbol(string symbol);

    /**
     * @dev Set the name of the token
     * @param _name The new token name
     */
    function setName(string _name)
    public
    onlyMinter
    {
        name = _name;
        emit SetName(name);
    }

    /**
     * @dev Set the symbol of the token
     * @param _symbol The new token symbol
     */
    function setSymbol(string _symbol)
    public
    onlyMinter
    {
        symbol = _symbol;
        emit SetSymbol(_symbol);
    }
}