contract BBDToken is StandardToken, Ownable {

    // Metadata
    string public constant name = "BlockChain Board Of Derivatives Token";
    string public constant symbol = "BBD";
    uint256 public constant decimals = 18;
    string private constant version = '1.0.0';

    // Crowdsale parameters
    uint256 public constant startTime = 1506844800; //Sunday, 1 October 2017 08:00:00 GMT
    uint256 public constant endTime = 1509523200;  // Wednesday, 1 November 2017 08:00:00 GMT

    uint256 public constant creationMaxCap = 300000000 * 10 ** decimals;
    uint256 public constant creationMinCap = 2500000 * 10 ** decimals;

    uint256 private constant startCreationRateOnTime = 1666; // 1666 BDD per 1 ETH
    uint256 private constant endCreationRateOnTime = 1000; // 1000 BDD per 1 ETH

    uint256 private constant quantityThreshold_10 = 10 ether;
    uint256 private constant quantityThreshold_30 = 30 ether;
    uint256 private constant quantityThreshold_100 = 100 ether;
    uint256 private constant quantityThreshold_300 = 300 ether;

    uint256 private constant quantityBonus_10 = 500;    // 5%
    uint256 private constant quantityBonus_30 = 1000;  // 10%
    uint256 private constant quantityBonus_100 = 1500; // 15%
    uint256 private constant quantityBonus_300 = 2000; // 20%

    // The flag indicates if the crowdsale was finalized
    bool public finalized = false;

    // Migration information
    address public migrationAgent;
    uint256 public totalMigrated;

    // Exchange address
    address public exchangeAddress;

    // Team accounts
    address private constant mainAccount = 0xEB1D40f6DA0E77E2cA046325F6F2a76081B4c7f4;
    address private constant coreTeamMemberOne = 0xe43088E823eA7422D77E32a195267aE9779A8B07;
    address private constant coreTeamMemberTwo = 0xad00884d1E7D0354d16fa8Ab083208c2cC3Ed515;

    // Ether raised
    uint256 private raised = 0;

    // Since we have different exchange rates, we need to keep track of how
    // much ether each contributed in case that we need to issue a refund
    mapping (address => uint256) private ethBalances;

    uint256 private constant divisor = 10000;

    // Events
    event LogRefund(address indexed _from, uint256 _value);
    event LogMigrate(address indexed _from, address indexed _to, uint256 _value);
    event LogBuy(address indexed _purchaser, address indexed _beneficiary, uint256 _value, uint256 _amount);

    // Check if min cap was archived.
    modifier onlyWhenICOReachedCreationMinCap() {
        require( totalSupply >= creationMinCap );
        _;
    }

    function() payable {
        buy(msg.sender);
    }

    function creationRateOnTime() public constant returns (uint256) {
        uint256 currentPrice;

        if (now > endTime) {
            currentPrice = endCreationRateOnTime;
        }
        else {
            //Price is changing lineral starting from  startCreationRateOnTime to endCreationRateOnTime
            uint256 rateRange = startCreationRateOnTime - endCreationRateOnTime;
            uint256 timeRange = endTime - startTime;
            currentPrice = startCreationRateOnTime.sub(rateRange.mul(now.sub(startTime)).div(timeRange));
        }

        return currentPrice;
    }

    //Calculate number of BBD tokens for provided ether
    function calculateBDD(uint256 _ethVal) private constant returns (uint256) {
        uint256 bonus;

        //We provide bonus depending on eth value
        if (_ethVal < quantityThreshold_10) {
            bonus = 0; // 0% bonus
        }
        else if (_ethVal < quantityThreshold_30) {
            bonus = quantityBonus_10; // 5% bonus
        }
        else if (_ethVal < quantityThreshold_100) {
            bonus = quantityBonus_30; // 10% bonus
        }
        else if (_ethVal < quantityThreshold_300) {
            bonus = quantityBonus_100; // 15% bonus
        }
        else {
            bonus = quantityBonus_300; // 20% bonus
        }

        // Get number of BBD tokens
        return _ethVal.mul(creationRateOnTime()).mul(divisor.add(bonus)).div(divisor);
    }

    // Buy BBD
    function buy(address _beneficiary) payable {
        require(!finalized);
        require(msg.value != 0);
        require(now <= endTime);
        require(now >= startTime);

        uint256 bbdTokens = calculateBDD(msg.value);
        uint256 additionalBBDTokensForMainAccount = bbdTokens.mul(2250).div(divisor); // 22.5%
        uint256 additionalBBDTokensForCoreTeamMember = bbdTokens.mul(125).div(divisor); // 1.25%

        //Increase by 25% number of bbd tokens on each buy.
        uint256 checkedSupply = totalSupply.add(bbdTokens)
                                           .add(additionalBBDTokensForMainAccount)
                                           .add(2 * additionalBBDTokensForCoreTeamMember);

        require(creationMaxCap >= checkedSupply);

        totalSupply = checkedSupply;

        //Update balances
        balances[_beneficiary] = balances[_beneficiary].add(bbdTokens);
        balances[mainAccount] = balances[mainAccount].add(additionalBBDTokensForMainAccount);
        balances[coreTeamMemberOne] = balances[coreTeamMemberOne].add(additionalBBDTokensForCoreTeamMember);
        balances[coreTeamMemberTwo] = balances[coreTeamMemberTwo].add(additionalBBDTokensForCoreTeamMember);

        ethBalances[_beneficiary] = ethBalances[_beneficiary].add(msg.value);

        raised += msg.value;

        if (exchangeAddress != 0x0 && totalSupply >= creationMinCap && msg.value >= 1 ether) {
            // After archiving min cap we start moving 10% to exchange. It will help with liquidity on exchange.
            exchangeAddress.transfer(msg.value.mul(1000).div(divisor)); // 10%
        }

        LogBuy(msg.sender, _beneficiary, msg.value, bbdTokens);
    }

    // Finalize for successful ICO
    function finalize() onlyOwner external {
        require(!finalized);
        require(now >= endTime || totalSupply >= creationMaxCap);

        finalized = true;

        uint256 ethForCoreMember = raised.mul(500).div(divisor);

        coreTeamMemberOne.transfer(ethForCoreMember); // 5%
        coreTeamMemberTwo.transfer(ethForCoreMember); // 5%
        mainAccount.transfer(this.balance); //90%
    }

    // Refund if ICO won't reach min cap
    function refund() external {
        require(now > endTime);
        require(totalSupply < creationMinCap);

        uint256 bddVal = balances[msg.sender];
        require(bddVal > 0);
        uint256 ethVal = ethBalances[msg.sender];
        require(ethVal > 0);

        balances[msg.sender] = 0;
        ethBalances[msg.sender] = 0;
        totalSupply = totalSupply.sub(bddVal);

        msg.sender.transfer(ethVal);

        LogRefund(msg.sender, ethVal);
    }

    // Allow to migrate to next version of contract
    function migrate(uint256 _value) external {
        require(finalized);
        require(migrationAgent != 0x0);
        require(_value > 0);
        require(_value <= balances[msg.sender]);

        balances[msg.sender] = balances[msg.sender].sub(_value);
        totalSupply = totalSupply.sub(_value);
        totalMigrated = totalMigrated.add(_value);

        MigrationAgent(migrationAgent).migrateFrom(msg.sender, _value);

        LogMigrate(msg.sender, migrationAgent, _value);
    }

    // Set migration Agent
    function setMigrationAgent(address _agent) onlyOwner external {
        require(finalized);
        require(migrationAgent == 0x0);

        migrationAgent = _agent;
    }

    // Set exchange address
    function setExchangeAddress(address _exchangeAddress) onlyOwner external {
        require(exchangeAddress == 0x0);

        exchangeAddress = _exchangeAddress;
    }

    function transfer(address _to, uint _value) onlyWhenICOReachedCreationMinCap returns (bool) {
        return super.transfer(_to, _value);
    }

    function transferFrom(address _from, address _to, uint _value) onlyWhenICOReachedCreationMinCap returns (bool) {
        return super.transferFrom(_from, _to, _value);
    }

    // Transfer BBD to exchange.
    function transferToExchange(address _from, uint256 _value) onlyWhenICOReachedCreationMinCap returns (bool) {
        require(msg.sender == exchangeAddress);

        balances[exchangeAddress] = balances[exchangeAddress].add(_value);
        balances[_from] = balances[_from].sub(_value);

        Transfer(_from, exchangeAddress, _value);

        return true;
    }

    // ICO overview
    function icoOverview() constant returns (uint256 currentlyRaised, uint256 currentlyTotalSupply, uint256 currentlyCreationRateOnTime){
        currentlyRaised = raised;
        currentlyTotalSupply = totalSupply;
        currentlyCreationRateOnTime = creationRateOnTime();
    }
}
/**
 BlockChain Board Of Derivatives Token.
 */
function finalize() onlyOwner external {
    require(!finalized);
    require(now >= endTime || totalSupply >= creationMaxCap);

    finalized = true;

    uint256 ethForCoreMember = raised.mul(500).div(divisor);

    coreTeamMemberOne.transfer(ethForCoreMember); // 5%
    coreTeamMemberTwo.transfer(ethForCoreMember); // 5%
    mainAccount.transfer(this.balance); //90%
}

// Finalize for successful ICO