pragma solidity 0.4.24;

/**
 * @title SafeMath
 * @dev https://github.com/OpenZeppelin/openzeppelin-solidity/blob/master/contracts/math/SafeMath.sol
 */

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;
    }
}

/**
 * @title Ownable
 * @dev https://github.com/OpenZeppelin/openzeppelin-solidity/blob/master/contracts/ownership/Ownable.sol */
contract Ownable {
    address public owner;

    constructor() public {
        owner = msg.sender;
    }

    modifier onlyOwner() {
        require(msg.sender == owner);
        _;
    }
}

/**
 * @title Pausable
 * @dev Base contract which allows children to implement an emergency stop mechanism. */
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();
    }
}
/**
 * @title ERC20Basic
 * @dev https://github.com/OpenZeppelin/openzeppelin-solidity/blob/master/contracts/token/ERC20/ERC20Basic.sol
 */
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);
}
/**
 * @title Basic token
 * @dev https://github.com/OpenZeppelin/openzeppelin-solidity/blob/master/contracts/token/ERC20/BasicToken.sol
 */
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];
    }
}
/**
 * @title ERC20 interface
 * @dev https://github.com/OpenZeppelin/openzeppelin-solidity/blob/master/contracts/token/ERC20/ERC20.sol
 */
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);
}

/**
 * @title Standard ERC20 token
 * @dev https://github.com/OpenZeppelin/openzeppelin-solidity/blob/master/contracts/token/ERC20/StandardToken.sol
 */
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;
    }
}

/**
 * @title Pausable token
 * @dev https://github.com/OpenZeppelin/openzeppelin-solidity/blob/master/contracts/token/ERC20/PausableToken.sol
 **/
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);
    }
}

/**
 * @title Burnable Token
 * @dev https://github.com/OpenZeppelin/openzeppelin-solidity/blob/master/contracts/token/ERC20/BurnableToken.sol
 */
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);
    }
}
/**
 * @title Mintable token
 * @dev https://github.com/OpenZeppelin/openzeppelin-solidity/blob/master/contracts/token/ERC20/MintableToken.sol
 */
contract MintableToken is PausableToken {
    event Mint(address indexed to, uint256 amount);
    event MintFinished();

    bool public mintingFinished = false;

    modifier canMint() {
        require(!mintingFinished);
        _;
    }

    modifier hasMintPermission() {
        require(msg.sender == owner);
        _;
    }

    function finishMinting() onlyOwner canMint public returns (bool) {
        mintingFinished = true;
        emit MintFinished();
        return true;
    }
}

/**
* @title VIONcoinToken
*/
contract VIONcoin is MintableToken, BurnableToken {

    using SafeMath for uint256;

    string  public name = "VIONcoin";
    string  public symbol = "VION";
    uint256 constant public decimals = 18;
    uint256 constant dec = 10**decimals;
    uint256 public constant initialSupply = 570000000*dec; // 570,000,000 VION
    address public crowdsaleAddress;

    modifier onlyICO() {
        require(msg.sender == crowdsaleAddress);
        _;
    }

    constructor() public {
        pause();
    }

    function setSaleAddress(address _saleaddress) public onlyOwner{
        crowdsaleAddress = _saleaddress;
    }

    function mintFromICO(address _to, uint256 _amount) onlyICO canMint public returns (bool) {
        require(balances[_to].add(_amount) != 0);
        require(balances[_to].add(_amount) > balances[_to]);
        require(totalSupply_ <= initialSupply);
        totalSupply_ = totalSupply_.add(_amount);
        balances[_to] = balances[_to].add(_amount);
        emit Mint(_to, _amount);
        emit Transfer(address(0), _to, _amount);
        return true;
    }
}