pragma solidity 0.4.24;




library SafeMath {

  
  function mul(uint256 a, uint256 b) internal pure returns (uint256 c) {
    if (a == 0) {
      return 0;
    }
    c = a * b;
    assert(c / a == b);
    return c;
  }

  
  function div(uint256 a, uint256 b) internal pure returns (uint256) {
    
    
    
    return a / b;
  }

  
  function sub(uint256 a, uint256 b) internal pure returns (uint256) {
    assert(b <= a);
    return a - b;
  }

  
  function add(uint256 a, uint256 b) internal pure returns (uint256 c) {
    c = a + b;
    assert(c >= a);
    return c;
  }
}




contract Ownable {
  address public owner;


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


  
  function Ownable() public {
    owner = msg.sender;
  }

  
  modifier onlyOwner() {
    require(msg.sender == owner);
    _;
  }

  
  function transferOwnership(address newOwner) public onlyOwner {
    require(newOwner != address(0));
    emit OwnershipTransferred(owner, newOwner);
    owner = newOwner;
  }

}




contract ERC20Basic {
  function totalSupply() public view returns (uint256);
  function balanceOf(address who) public view returns (uint256);
  function transfer(address to, uint256 value) public returns (bool);
  event Transfer(address indexed from, address indexed to, uint256 value);
}




contract ERC20 is ERC20Basic {
  function allowance(address owner, address spender) public view returns (uint256);
  function transferFrom(address from, address to, uint256 value) public returns (bool);
  function approve(address spender, uint256 value) public returns (bool);
  event Approval(address indexed owner, address indexed spender, uint256 value);
}




contract Crowdsale {
  using SafeMath for uint256;

  
  ERC20 public token;

  
  address public wallet;

  
  uint256 public rate;

  
  uint256 public weiRaised;

  
  event TokenPurchase(address indexed purchaser, address indexed beneficiary, uint256 value, uint256 amount);

  
  function Crowdsale(uint256 _rate, address _wallet, ERC20 _token) public {
    require(_rate > 0);
    require(_wallet != address(0));
    require(_token != address(0));

    rate = _rate;
    wallet = _wallet;
    token = _token;
  }

  
  
  

  
  function () external payable {
    buyTokens(msg.sender);
  }

  
  function buyTokens(address _beneficiary) public payable {

    uint256 weiAmount = msg.value;
    _preValidatePurchase(_beneficiary, weiAmount);

    
    uint256 tokens = _getTokenAmount(weiAmount);

    
    weiRaised = weiRaised.add(weiAmount);

    _processPurchase(_beneficiary, tokens);
    emit TokenPurchase(
      msg.sender,
      _beneficiary,
      weiAmount,
      tokens
    );

    _updatePurchasingState(_beneficiary, weiAmount);

    _forwardFunds();
    _postValidatePurchase(_beneficiary, weiAmount);
  }

  
  
  

  
  function _preValidatePurchase(address _beneficiary, uint256 _weiAmount) internal {
    require(_beneficiary != address(0));
    require(_weiAmount != 0);
  }

  
  function _postValidatePurchase(address _beneficiary, uint256 _weiAmount) internal {
    
  }

  
  function _deliverTokens(address _beneficiary, uint256 _tokenAmount) internal {
    token.transfer(_beneficiary, _tokenAmount);
  }

  
  function _processPurchase(address _beneficiary, uint256 _tokenAmount) internal {
    _deliverTokens(_beneficiary, _tokenAmount);
  }

  
  function _updatePurchasingState(address _beneficiary, uint256 _weiAmount) internal {
    
  }

  
  function _getTokenAmount(uint256 _weiAmount) internal view returns (uint256) {
    return _weiAmount.mul(rate);
  }

  
  function _forwardFunds() internal {
    wallet.transfer(msg.value);
  }
}




contract TimedCrowdsale is Crowdsale {
  using SafeMath for uint256;

  uint256 public openingTime;
  uint256 public closingTime;

  
  modifier onlyWhileOpen {
    
    require(block.timestamp >= openingTime && block.timestamp <= closingTime);
    _;
  }

  
  function TimedCrowdsale(uint256 _openingTime, uint256 _closingTime) public {
    
    require(_openingTime >= block.timestamp);
    require(_closingTime >= _openingTime);

    openingTime = _openingTime;
    closingTime = _closingTime;
  }

  
  function hasClosed() public view returns (bool) {
    
    return block.timestamp > closingTime;
  }

  
  function _preValidatePurchase(address _beneficiary, uint256 _weiAmount) internal onlyWhileOpen {
    super._preValidatePurchase(_beneficiary, _weiAmount);
  }

}




contract FinalizableCrowdsale is TimedCrowdsale, Ownable {
  using SafeMath for uint256;

  bool public isFinalized = false;

  event Finalized();

  
  function finalize() onlyOwner public {
    require(!isFinalized);
    require(hasClosed());

    finalization();
    emit Finalized();

    isFinalized = true;
  }

  
  function finalization() internal {
  }

}




contract BasicToken is ERC20Basic {
  using SafeMath for uint256;

  mapping(address => uint256) balances;

  uint256 totalSupply_;

  
  function totalSupply() public view returns (uint256) {
    return totalSupply_;
  }

  
  function transfer(address _to, uint256 _value) public returns (bool) {
    require(_to != address(0));
    require(_value <= balances[msg.sender]);

    balances[msg.sender] = balances[msg.sender].sub(_value);
    balances[_to] = balances[_to].add(_value);
    emit Transfer(msg.sender, _to, _value);
    return true;
  }

  
  function balanceOf(address _owner) public view returns (uint256) {
    return balances[_owner];
  }

}




contract StandardToken is ERC20, BasicToken {

  mapping (address => mapping (address => uint256)) internal allowed;


  
  function transferFrom(address _from, address _to, uint256 _value) public returns (bool) {
    require(_to != address(0));
    require(_value <= balances[_from]);
    require(_value <= allowed[_from][msg.sender]);

    balances[_from] = balances[_from].sub(_value);
    balances[_to] = balances[_to].add(_value);
    allowed[_from][msg.sender] = allowed[_from][msg.sender].sub(_value);
    emit Transfer(_from, _to, _value);
    return true;
  }

  
  function approve(address _spender, uint256 _value) public returns (bool) {
    allowed[msg.sender][_spender] = _value;
    emit Approval(msg.sender, _spender, _value);
    return true;
  }

  
  function allowance(address _owner, address _spender) public view returns (uint256) {
    return allowed[_owner][_spender];
  }

  
  function increaseApproval(address _spender, uint _addedValue) public returns (bool) {
    allowed[msg.sender][_spender] = allowed[msg.sender][_spender].add(_addedValue);
    emit Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
    return true;
  }

  
  function decreaseApproval(address _spender, uint _subtractedValue) public returns (bool) {
    uint oldValue = allowed[msg.sender][_spender];
    if (_subtractedValue > oldValue) {
      allowed[msg.sender][_spender] = 0;
    } else {
      allowed[msg.sender][_spender] = oldValue.sub(_subtractedValue);
    }
    emit Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
    return true;
  }

}




contract MintableToken is StandardToken, Ownable {
  event Mint(address indexed to, uint256 amount);
  event MintFinished();

  bool public mintingFinished = false;


  modifier canMint() {
    require(!mintingFinished);
    _;
  }

  
  function mint(address _to, uint256 _amount) onlyOwner canMint public returns (bool) {
    totalSupply_ = totalSupply_.add(_amount);
    balances[_to] = balances[_to].add(_amount);
    emit Mint(_to, _amount);
    emit Transfer(address(0), _to, _amount);
    return true;
  }

  
  function finishMinting() onlyOwner canMint public returns (bool) {
    mintingFinished = true;
    emit MintFinished();
    return true;
  }
}




contract MintedCrowdsale is Crowdsale {

  
  function _deliverTokens(address _beneficiary, uint256 _tokenAmount) internal {
    require(MintableToken(token).mint(_beneficiary, _tokenAmount));
  }
}





contract PostKYCCrowdsale is Crowdsale, Ownable {

    struct Investment {
        bool isVerified;         
        uint totalWeiInvested;   
        
        uint pendingTokenAmount;
    }

    
    uint public pendingWeiAmount = 0;

    
    mapping(address => Investment) public investments;

    
    
    event InvestorVerified(address investor);

    
    
    
    event TokensDelivered(address investor, uint amount);

    
    
    
    event InvestmentWithdrawn(address investor, uint value);

    
    
    function verifyInvestors(address[] _investors) public onlyOwner {
        for (uint i = 0; i < _investors.length; ++i) {
            address investor = _investors[i];
            Investment storage investment = investments[investor];

            if (!investment.isVerified) {
                investment.isVerified = true;

                emit InvestorVerified(investor);

                uint pendingTokenAmount = investment.pendingTokenAmount;
                
                if (pendingTokenAmount > 0) {
                    investment.pendingTokenAmount = 0;

                    _forwardFunds(investment.totalWeiInvested);
                    _deliverTokens(investor, pendingTokenAmount);

                    emit TokensDelivered(investor, pendingTokenAmount);
                }
            }
        }
    }

    
    
    function withdrawInvestment() public {
        Investment storage investment = investments[msg.sender];

        require(!investment.isVerified);

        uint totalWeiInvested = investment.totalWeiInvested;

        require(totalWeiInvested > 0);

        investment.totalWeiInvested = 0;
        investment.pendingTokenAmount = 0;

        pendingWeiAmount = pendingWeiAmount.sub(totalWeiInvested);

        msg.sender.transfer(totalWeiInvested);

        emit InvestmentWithdrawn(msg.sender, totalWeiInvested);

        assert(pendingWeiAmount <= address(this).balance);
    }

    
    
    
    function _preValidatePurchase(address _beneficiary, uint _weiAmount) internal {
        
        require(_beneficiary == msg.sender);

        super._preValidatePurchase(_beneficiary, _weiAmount);
    }

    
    
    function _processPurchase(address, uint _tokenAmount) internal {
        Investment storage investment = investments[msg.sender];
        investment.totalWeiInvested = investment.totalWeiInvested.add(msg.value);

        if (investment.isVerified) {
            
            _deliverTokens(msg.sender, _tokenAmount);
            emit TokensDelivered(msg.sender, _tokenAmount);
        } else {
            
            investment.pendingTokenAmount = investment.pendingTokenAmount.add(_tokenAmount);
            pendingWeiAmount = pendingWeiAmount.add(msg.value);
        }
    }

    
    function _forwardFunds() internal {
        
        
        if (investments[msg.sender].isVerified) {
            super._forwardFunds();
        }
    }

    
    
    function _forwardFunds(uint _weiAmount) internal {
        pendingWeiAmount = pendingWeiAmount.sub(_weiAmount);
        wallet.transfer(_weiAmount);
    }

    
    
    function _postValidatePurchase(address, uint _weiAmount) internal {
        super._postValidatePurchase(msg.sender, _weiAmount);
        
        assert(pendingWeiAmount <= address(this).balance);
    }

}




contract BurnableToken is BasicToken {

  event Burn(address indexed burner, uint256 value);

  
  function burn(uint256 _value) public {
    _burn(msg.sender, _value);
  }

  function _burn(address _who, uint256 _value) internal {
    require(_value <= balances[_who]);
    
    

    balances[_who] = balances[_who].sub(_value);
    totalSupply_ = totalSupply_.sub(_value);
    emit Burn(_who, _value);
    emit Transfer(_who, address(0), _value);
  }
}




contract CappedToken is MintableToken {

  uint256 public cap;

  function CappedToken(uint256 _cap) public {
    require(_cap > 0);
    cap = _cap;
  }

  
  function mint(address _to, uint256 _amount) onlyOwner canMint public returns (bool) {
    require(totalSupply_.add(_amount) <= cap);

    return super.mint(_to, _amount);
  }

}




contract Pausable is Ownable {
  event Pause();
  event Unpause();

  bool public paused = false;


  
  modifier whenNotPaused() {
    require(!paused);
    _;
  }

  
  modifier whenPaused() {
    require(paused);
    _;
  }

  
  function pause() onlyOwner whenNotPaused public {
    paused = true;
    emit Pause();
  }

  
  function unpause() onlyOwner whenPaused public {
    paused = false;
    emit Unpause();
  }
}




contract PausableToken is StandardToken, Pausable {

  function transfer(address _to, uint256 _value) public whenNotPaused returns (bool) {
    return super.transfer(_to, _value);
  }

  function transferFrom(address _from, address _to, uint256 _value) public whenNotPaused returns (bool) {
    return super.transferFrom(_from, _to, _value);
  }

  function approve(address _spender, uint256 _value) public whenNotPaused returns (bool) {
    return super.approve(_spender, _value);
  }

  function increaseApproval(address _spender, uint _addedValue) public whenNotPaused returns (bool success) {
    return super.increaseApproval(_spender, _addedValue);
  }

  function decreaseApproval(address _spender, uint _subtractedValue) public whenNotPaused returns (bool success) {
    return super.decreaseApproval(_spender, _subtractedValue);
  }
}





contract VreoToken is CappedToken, PausableToken, BurnableToken {

    uint public constant TOTAL_TOKEN_CAP = 700000000e18;  

    string public name = "MERO Token";
    string public symbol = "MERO";
    uint8 public decimals = 18;

    
    constructor() public CappedToken(TOTAL_TOKEN_CAP) {
        pause();
    }

}





contract VreoTokenSale is PostKYCCrowdsale, FinalizableCrowdsale, MintedCrowdsale {

    
    uint public constant TOTAL_TOKEN_CAP_OF_SALE = 450000000e18;  

    
    uint public constant TOKEN_SHARE_OF_TEAM     =  85000000e18;  
    uint public constant TOKEN_SHARE_OF_ADVISORS =  58000000e18;  
    uint public constant TOKEN_SHARE_OF_LEGALS   =  57000000e18;  
    uint public constant TOKEN_SHARE_OF_BOUNTY   =  50000000e18;  

    
    uint public constant BONUS_PCT_IN_ICONIQ_SALE       = 30;  
    uint public constant BONUS_PCT_IN_VREO_SALE_PHASE_1 = 20;
    uint public constant BONUS_PCT_IN_VREO_SALE_PHASE_2 = 10;

    
    uint public constant ICONIQ_SALE_OPENING_TIME   = 1531123200;  
    uint public constant ICONIQ_SALE_CLOSING_TIME   = 1532376000;  
    uint public constant VREO_SALE_OPENING_TIME     = 1533369600;  
    uint public constant VREO_SALE_PHASE_1_END_TIME = 1533672000;  
    uint public constant VREO_SALE_PHASE_2_END_TIME = 1534276800;  
    uint public constant VREO_SALE_CLOSING_TIME     = 1535832000;  
    uint public constant KYC_VERIFICATION_END_TIME  = 1537041600;  

    
    uint public constant ICONIQ_TOKENS_NEEDED_PER_INVESTED_WEI = 450;

    
    ERC20Basic public iconiqToken;

    
    address public teamAddress;
    address public advisorsAddress;
    address public legalsAddress;
    address public bountyAddress;

    
    uint public remainingTokensForSale;

    
    
    event RateChanged(uint newRate);

    
    
    
    
    
    
    
    
    
    constructor(
        VreoToken _token,
        uint _rate,
        ERC20Basic _iconiqToken,
        address _teamAddress,
        address _advisorsAddress,
        address _legalsAddress,
        address _bountyAddress,
        address _wallet
    )
        public
        Crowdsale(_rate, _wallet, _token)
        TimedCrowdsale(ICONIQ_SALE_OPENING_TIME, VREO_SALE_CLOSING_TIME)
    {
        
        require(_token.cap() >= TOTAL_TOKEN_CAP_OF_SALE
                                + TOKEN_SHARE_OF_TEAM
                                + TOKEN_SHARE_OF_ADVISORS
                                + TOKEN_SHARE_OF_LEGALS
                                + TOKEN_SHARE_OF_BOUNTY);

        
        require(address(_iconiqToken) != address(0)
                && _teamAddress != address(0)
                && _advisorsAddress != address(0)
                && _legalsAddress != address(0)
                && _bountyAddress != address(0));

        iconiqToken = _iconiqToken;
        teamAddress = _teamAddress;
        advisorsAddress = _advisorsAddress;
        legalsAddress = _legalsAddress;
        bountyAddress = _bountyAddress;

        remainingTokensForSale = TOTAL_TOKEN_CAP_OF_SALE;
    }

    
    
    
    function distributePresale(address[] _investors, uint[] _amounts) public onlyOwner {
        require(!hasClosed());
        require(_investors.length == _amounts.length);

        uint totalAmount = 0;

        for (uint i = 0; i < _investors.length; ++i) {
            VreoToken(token).mint(_investors[i], _amounts[i]);
            totalAmount = totalAmount.add(_amounts[i]);
        }

        require(remainingTokensForSale >= totalAmount);
        remainingTokensForSale = remainingTokensForSale.sub(totalAmount);
    }

    
    
    function setRate(uint _newRate) public onlyOwner {
        
        
        require(rate / 10 < _newRate && _newRate < 10 * rate);

        rate = _newRate;

        emit RateChanged(_newRate);
    }

    
    function withdrawInvestment() public {
        require(hasClosed());

        super.withdrawInvestment();
    }

    
    
    function iconiqSaleOngoing() public view returns (bool) {
        return ICONIQ_SALE_OPENING_TIME <= now && now <= ICONIQ_SALE_CLOSING_TIME;
    }

    
    
    function vreoSaleOngoing() public view returns (bool) {
        return VREO_SALE_OPENING_TIME <= now && now <= VREO_SALE_CLOSING_TIME;
    }

    
    
    
    function getIconiqMaxInvestment(address _investor) public view returns (uint) {
        uint iconiqBalance = iconiqToken.balanceOf(_investor);
        uint prorataLimit = iconiqBalance.div(ICONIQ_TOKENS_NEEDED_PER_INVESTED_WEI);

        
        require(prorataLimit >= investments[_investor].totalWeiInvested);
        return prorataLimit.sub(investments[_investor].totalWeiInvested);
    }

    
    
    
    function _preValidatePurchase(address _beneficiary, uint _weiAmount) internal {
        super._preValidatePurchase(_beneficiary, _weiAmount);

        require(iconiqSaleOngoing() && getIconiqMaxInvestment(msg.sender) >= _weiAmount || vreoSaleOngoing());
    }

    
    
    
    function _getTokenAmount(uint _weiAmount) internal view returns (uint) {
        uint tokenAmount = super._getTokenAmount(_weiAmount);

        if (now <= ICONIQ_SALE_CLOSING_TIME) {
            return tokenAmount.mul(100 + BONUS_PCT_IN_ICONIQ_SALE).div(100);
        }

        if (now <= VREO_SALE_PHASE_1_END_TIME) {
            return tokenAmount.mul(100 + BONUS_PCT_IN_VREO_SALE_PHASE_1).div(100);
        }

        if (now <= VREO_SALE_PHASE_2_END_TIME) {
            return tokenAmount.mul(100 + BONUS_PCT_IN_VREO_SALE_PHASE_2).div(100);
        }

        return tokenAmount;  
    }

    
    
    
    function _deliverTokens(address _beneficiary, uint _tokenAmount) internal {
        require(remainingTokensForSale >= _tokenAmount);
        remainingTokensForSale = remainingTokensForSale.sub(_tokenAmount);

        super._deliverTokens(_beneficiary, _tokenAmount);
    }

    
    function finalization() internal {
        require(now >= KYC_VERIFICATION_END_TIME);

        VreoToken(token).mint(teamAddress, TOKEN_SHARE_OF_TEAM);
        VreoToken(token).mint(advisorsAddress, TOKEN_SHARE_OF_ADVISORS);
        VreoToken(token).mint(legalsAddress, TOKEN_SHARE_OF_LEGALS);
        VreoToken(token).mint(bountyAddress, TOKEN_SHARE_OF_BOUNTY);

        VreoToken(token).finishMinting();
        VreoToken(token).unpause();

        super.finalization();
    }

}