// Contract: Gambler
// Target function: function totalSupply () public override view returns (uint256)
pragma solidity ^0.8.0;

interface Token {
  /**
   * Get total number of tokens in circulation.
   *
   * @return supply total number of tokens in circulation
   */
  function totalSupply () external view returns (uint256 supply);

  /**
   * Get number of tokens currently belonging to given owner.
   *
   * @param _owner address to get number of tokens currently belonging to the
   *        owner of
   * @return balance number of tokens currently belonging to the owner of given address
   */
  function balanceOf (address _owner) external view returns (uint256 balance);

  /**
   * Transfer given number of tokens from message sender to given recipient.
   *
   * @param _to address to transfer tokens to the owner of
   * @param _value number of tokens to transfer to the owner of given address
   * @return success true if tokens were transferred successfully, false otherwise
   */
  function transfer (address _to, uint256 _value)
  external returns (bool success);

  /**
   * Transfer given number of tokens from given owner to given recipient.
   *
   * @param _from address to transfer tokens from the owner of
   * @param _to address to transfer tokens to the owner of
   * @param _value number of tokens to transfer from given owner to given
   *        recipient
   * @return success true if tokens were transferred successfully, false otherwise
   */
  function transferFrom (address _from, address _to, uint256 _value)
  external returns (bool success);

  /**
   * Allow given spender to transfer given number of tokens from message sender.
   *
   * @param _spender address to allow the owner of to transfer tokens from
   *        message sender
   * @param _value number of tokens to allow to transfer
   * @return success true if token transfer was successfully approved, false otherwise
   */
  function approve (address _spender, uint256 _value)
  external returns (bool success);

  /**
   * Tell how many tokens given spender is currently allowed to transfer from
   * given owner.
   *
   * @param _owner address to get number of tokens allowed to be transferred
   *        from the owner of
   * @param _spender address to get number of tokens allowed to be transferred
   *        by the owner of
   * @return remaining number of tokens given spender is currently allowed to transfer
   *         from given owner
   */
  function allowance (address _owner, address _spender)
  external view returns (uint256 remaining);

  /**
   * Logged when tokens were transferred from one owner to another.
   *
   * @param _from address of the owner, tokens were transferred from
   * @param _to address of the owner, tokens were transferred to
   * @param _value number of tokens transferred
   */
  event Transfer (address indexed _from, address indexed _to, uint256 _value);

  /**
   * Logged when owner approved his tokens to be transferred by some spender.
   *
   * @param _owner owner who approved his tokens to be transferred
   * @param _spender spender who were allowed to transfer the tokens belonging
   *        to the owner
   * @param _value number of tokens belonging to the owner, approved to be
   *        transferred by the spender
   */
  event Approval (
    address indexed _owner, address indexed _spender, uint256 _value);
}


/**
 * Abstract Token Smart Contract that could be used as a base contract for
 * ERC-20 token contracts.
 */
abstract contract AbstractToken is Token {
  /**
   * Create new Abstract Token contract.
   */
  constructor () {
    // Do nothing
  }

  /**
   * Get number of tokens currently belonging to given owner.
   *
   * @param _owner address to get number of tokens currently belonging to the
   *        owner of
   * @return balance number of tokens currently belonging to the owner of given address
   */
  function balanceOf (address _owner) public override virtual view returns (uint256 balance) {
    return accounts [_owner];
  }

  /**
   * Transfer given number of tokens from message sender to given recipient.
   *
   * @param _to address to transfer tokens to the owner of
   * @param _value number of tokens to transfer to the owner of given address
   * @return success true if tokens were transferred successfully, false otherwise
   */
  function transfer (address _to, uint256 _value)
  public override virtual returns (bool success) {
    uint256 fromBalance = accounts [msg.sender];
    if (fromBalance < _value) return false;
    if (_value > 0 && msg.sender != _to) {
      accounts [msg.sender] = fromBalance - _value;
      accounts [_to] = accounts [_to] + _value;
    }
    emit Transfer (msg.sender, _to, _value);
    return true;
  }

  /**
   * Transfer given number of tokens from given owner to given recipient.
   *
   * @param _from address to transfer tokens from the owner of
   * @param _to address to transfer tokens to the owner of
   * @param _value number of tokens to transfer from given owner to given
   *        recipient
   * @return success true if tokens were transferred successfully, false otherwise
   */
  function transferFrom (address _from, address _to, uint256 _value)
  public override virtual returns (bool success) {
    uint256 spenderAllowance = allowances [_from][msg.sender];
    if (spenderAllowance < _value) return false;
    uint256 fromBalance = accounts [_from];
    if (fromBalance < _value) return false;

    allowances [_from][msg.sender] =
      spenderAllowance - _value;

    if (_value > 0 && _from != _to) {
      accounts [_from] = fromBalance - _value;
      accounts [_to] = accounts [_to] + _value;
    }
    emit Transfer (_from, _to, _value);
    return true;
  }

  /**
   * Allow given spender to transfer given number of tokens from message sender.
   *
   * @param _spender address to allow the owner of to transfer tokens from
   *        message sender
   * @param _value number of tokens to allow to transfer
   * @return success true if token transfer was successfully approved, false otherwise
   */
  function approve (address _spender, uint256 _value)
  public override virtual returns (bool success) {
    allowances [msg.sender][_spender] = _value;
    emit Approval (msg.sender, _spender, _value);

    return true;
  }

  /**
   * Tell how many tokens given spender is currently allowed to transfer from
   * given owner.
   *
   * @param _owner address to get number of tokens allowed to be transferred
   *        from the owner of
   * @param _spender address to get number of tokens allowed to be transferred
   *        by the owner of
   * @return remaining number of tokens given spender is currently allowed to transfer
   *         from given owner
   */
  function allowance (address _owner, address _spender)
  public override virtual view returns (uint256 remaining) {
    return allowances [_owner][_spender];
  }

  /**
   * @dev Mapping from addresses of token holders to the numbers of tokens belonging
   * to these token holders.
   */
  mapping (address => uint256) internal accounts;

  /**
   * @dev Mapping from addresses of token holders to the mapping of addresses of
   * spenders to the allowances set by these token holders to these spenders.
   */
  mapping (address => mapping (address => uint256)) internal allowances;
}


/**
 * GMBLR Token Smart Contract: EIP-20 compatible token smart contract that
 * manages GMBLR tokens.
 */
contract Gambler is AbstractToken {
  // /**
  //  * @dev Fee denominator (0.001%).
  //  */
  // uint256 constant internal FEE_DENOMINATOR = 100000;

  // /**
  //  * @dev Maximum fee numerator (100%).
  //  */
  // uint256 constant internal MAX_FEE_NUMERATOR = FEE_DENOMINATOR;

  // /**
  //  * @dev Maximum allowed number of tokens in circulation.
  //  */
   uint256 constant internal MAX_TOKENS_COUNT = 10**13;
  // uint256 constant internal MAX_TOKENS_COUNT = 
  //   0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff /
  //   MAX_FEE_NUMERATOR;

  /**
   * @dev Address flag that marks black listed addresses.
   */
  uint256 constant internal BLACK_LIST_FLAG = 0x01;

  /**
   * Create GMBLR Token smart contract with message sender as an owner.
   */
  constructor () {
    owner = msg.sender;
  }

  /**
   * Get name of the token.
   *
   * @return name of the token
   */
  function name () public pure returns (string memory) {
    return "Gambler Coin";
  }

  /**
   * Get symbol of the token.
   *
   * @return symbol of the token
   */
  function symbol () public pure returns (string memory) {
    return "GMBLR";
  }

  /**
   * Get number of decimals for the token.
   *
   * @return number of decimals for the token
   */
  function decimals () public pure returns (uint8) {
    return 3;
  }