contract xCryptToken is TokenBase {
  uint256 public constant ALLOCATION_FOR_PARTNERS_AND_ADVISORS = 16 * MILLION;
  uint256 public constant ALLOCATION_FOR_TEAM = 30 * MILLION;
  uint256 public constant ALLOCATION_FOR_BONUS_AND_RESERVES = 18 * MILLION;
  uint256 public constant ALLOCATION_FOR_BOUNTIES = 6 * MILLION;

  mapping(bytes32 => bool) private mintingList;

  ///@notice Checks if the minting for the supplied key was already performed.
  ///@param _key The key or category name of minting.
  modifier whenNotMinted(string _key) {
    if(mintingList[computeHash(_key)]) {
      revert("Duplicate minting key supplied.");
    }

    _;
  }

  ///@notice Mints the below-mentioned amount of tokens allocated to the partners and advisors.
  function mintPartnerAndAdvisorTokens() external onlyAdmin returns(bool) {
    return mintOnce("partnerAndAdvisor", msg.sender, ALLOCATION_FOR_PARTNERS_AND_ADVISORS);
  }

  ///@notice Mints the below-mentioned amount of tokens allocated to the xCrypt team.
  function mintTeamTokens() external onlyAdmin returns(bool) {
    return mintOnce("team", msg.sender, ALLOCATION_FOR_TEAM);
  }

  ///@notice Mints the below-mentioned amount of tokens allocated to bonus and reserves.
  function mintBonusAndReservesTokens() external onlyAdmin returns(bool) {
    return mintOnce("bonusAndReserves", msg.sender, ALLOCATION_FOR_BONUS_AND_RESERVES);
  }

  ///@notice Mints the below-mentioned amount of tokens allocated to bounties.
  function mintBountyTokens() external onlyAdmin returns(bool) {
    return mintOnce("bounty", msg.sender, ALLOCATION_FOR_BOUNTIES);
  }

  ///@notice Computes keccak256 hash of the supplied value.
  ///@param _key The string value to compute hash from.
  function computeHash(string _key) private pure returns(bytes32) {
    return keccak256(abi.encodePacked(_key));
  }

  ///@notice Mints the tokens only once against the supplied key (category).
  ///@param _key The key or the category of the allocation to mint the tokens for.
  ///@param _to The address receiving the minted tokens.
  ///@param _amount The amount of tokens to mint.
  function mintOnce(string _key, address _to, uint256 _amount) private whenNotPaused whenNotMinted(_key) returns(bool) {
    mintingList[computeHash(_key)] = true;
    return mintTokens(_to, _amount);
  }
}
///@title xCrypt Token
///@author Binod Nirvan
///@notice XCRYPT is the first crypto ecosystem with a high added value
///with the heart in its exchange: Hybrid, ready for STO
///and for a marketplace made for the ERC721. We created this
///end to end system which includes a Debit Card
///and a Social Media Trading system which is
///an advanced investment solution, which enables trading
///on one account managed by a skillfull and experienced trader
///using his own funds and joint funds invested by other traders
///in his SMT account. This ecosystem is made to be at the same level
///as the world’s big players, and even surpass them, for we are already
///suitable in this field’s future.
function computeHash(string _key) private pure returns(bytes32) {
    return keccak256(abi.encodePacked(_key));
  }
///@notice Computes keccak256 hash of the supplied value.
///@param _key The string value to compute hash from.