pragma solidity 0.4.15;

/**
 * @title ERC20Basic
 * @dev Simpler version of ERC20 interface
 * @dev see https://github.com/ethereum/EIPs/issues/179
 */
contract ERC20Basic {
  uint256 public totalSupply;
  function balanceOf(address who) constant returns (uint256);
  function transfer(address to, uint256 value) returns (bool);
  event Transfer(address indexed from, address indexed to, uint256 value);
}

/**
 * @title SafeMath
 * @dev Math operations with safety checks that throw on error
 */
library SafeMath {
  function mul(uint256 a, uint256 b) internal constant returns (uint256) {
    uint256 c = a * b;
    assert(a == 0 || c / a == b);
    return c;
  }

  function div(uint256 a, uint256 b) internal constant returns (uint256) {
    // assert(b > 0); // Solidity automatically throws when dividing by 0
    uint256 c = a / b;
    // assert(a == b * c + a % b); // There is no case in which this doesn't hold
    return c;
  }

  function sub(uint256 a, uint256 b) internal constant returns (uint256) {
    assert(b <= a);
    return a - b;
  }

  function add(uint256 a, uint256 b) internal constant returns (uint256) {
    uint256 c = a + b;
    assert(c >= a);
    return c;
  }
}


/**
 * @title Basic token
 * @dev Basic version of StandardToken, with no allowances. 
 */
contract BasicToken is ERC20Basic {
  using SafeMath for uint256;

  mapping(address => uint256) balances;

  /**
  * @dev transfer token for a specified address
  * @param _to The address to transfer to.
  * @param _value The amount to be transferred.
  */
  function transfer(address _to, uint256 _value) returns (bool) {
    balances[msg.sender] = balances[msg.sender].sub(_value);
    balances[_to] = balances[_to].add(_value);
    Transfer(msg.sender, _to, _value);
    return true;
  }

  /**
  * @dev Gets the balance of the specified address.
  * @param _owner The address to query the the balance of. 
  * @return An uint256 representing the amount owned by the passed address.
  */
  function balanceOf(address _owner) constant returns (uint256 balance) {
    return balances[_owner];
  }

}

/**
 * @title ERC20 interface
 * @dev see https://github.com/ethereum/EIPs/issues/20
 */
contract ERC20 is ERC20Basic {
  function allowance(address owner, address spender) constant returns (uint256);
  function transferFrom(address from, address to, uint256 value) returns (bool);
  function approve(address spender, uint256 value) returns (bool);
  event Approval(address indexed owner, address indexed spender, uint256 value);
}



/**
 * @title Standard ERC20 token
 *
 * @dev Implementation of the basic standard token.
 * @dev https://github.com/ethereum/EIPs/issues/20
 * @dev Based on code by FirstBlood: https://github.com/Firstbloodio/token/blob/master/smart_contract/FirstBloodToken.sol
 */
contract StandardToken is ERC20, BasicToken {

  mapping (address => mapping (address => uint256)) allowed;


  /**
   * @dev Transfer tokens from one address to another
   * @param _from address The address which you want to send tokens from
   * @param _to address The address which you want to transfer to
   * @param _value uint256 the amout of tokens to be transfered
   */
  function transferFrom(address _from, address _to, uint256 _value) returns (bool) {
    var _allowance = allowed[_from][msg.sender];

    // Check is not needed because sub(_allowance, _value) will already throw if this condition is not met
    // require (_value <= _allowance);

    balances[_to] = balances[_to].add(_value);
    balances[_from] = balances[_from].sub(_value);
    allowed[_from][msg.sender] = _allowance.sub(_value);
    Transfer(_from, _to, _value);
    return true;
  }

  /**
   * @dev Aprove the passed address to spend the specified amount of tokens on behalf of msg.sender.
   * @param _spender The address which will spend the funds.
   * @param _value The amount of tokens to be spent.
   */
  function approve(address _spender, uint256 _value) returns (bool) {

    // To change the approve amount you first have to reduce the addresses`
    //  allowance to zero by calling `approve(_spender, 0)` if it is not
    //  already 0 to mitigate the race condition described here:
    //  https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
    require((_value == 0) || (allowed[msg.sender][_spender] == 0));

    allowed[msg.sender][_spender] = _value;
    Approval(msg.sender, _spender, _value);
    return true;
  }

  /**
   * @dev Function to check the amount of tokens that an owner allowed to a spender.
   * @param _owner address The address which owns the funds.
   * @param _spender address The address which will spend the funds.
   * @return A uint256 specifing the amount of tokens still avaible for the spender.
   */
  function allowance(address _owner, address _spender) constant returns (uint256 remaining) {
    return allowed[_owner][_spender];
  }

}


/// @title StandardToken which circulation can be delayed and started by another contract.
/// @dev To be used as a mixin contract.
/// The contract is created in disabled state: circulation is disabled.
contract CirculatingToken is StandardToken {

    event CirculationEnabled();

    modifier requiresCirculation {
        require(m_isCirculating);
        _;
    }


    // PUBLIC interface

    function transfer(address _to, uint256 _value) requiresCirculation returns (bool) {
        return super.transfer(_to, _value);
    }

    function transferFrom(address _from, address _to, uint256 _value) requiresCirculation returns (bool) {
        return super.transferFrom(_from, _to, _value);
    }

    function approve(address _spender, uint256 _value) requiresCirculation returns (bool) {
        return super.approve(_spender, _value);
    }


    // INTERNAL functions

    function enableCirculation() internal returns (bool) {
        if (m_isCirculating)
            return false;

        m_isCirculating = true;
        CirculationEnabled();
        return true;
    }


    // FIELDS

    /// @notice are the circulation started?
    bool public m_isCirculating;
}

/// note: during any ownership changes all pending operations (waiting for more signatures) are cancelled
// TODO acceptOwnership
contract multiowned {

	// TYPES

    // struct for the status of a pending operation.
    struct MultiOwnedOperationPendingState {
        // count of confirmations needed
        uint yetNeeded;

        // bitmap of confirmations where owner #ownerIndex's decision corresponds to 2**ownerIndex bit
        uint ownersDone;

        // position of this operation key in m_multiOwnedPendingIndex
        uint index;
    }

	// EVENTS

    event Confirmation(address owner, bytes32 operation);
    event Revoke(address owner, bytes32 operation);
    event FinalConfirmation(address owner, bytes32 operation);

    // some others are in the case of an owner changing.
    event OwnerChanged(address oldOwner, address newOwner);
    event OwnerAdded(address newOwner);
    event OwnerRemoved(address oldOwner);

    // the last one is emitted if the required signatures change
    event RequirementChanged(uint newRequirement);

	// MODIFIERS

    // simple single-sig function modifier.
    modifier onlyowner {
        require(isOwner(msg.sender));
        _;
    }
    // multi-sig function modifier: the operation must have an intrinsic hash in order
    // that later attempts can be realised as the same underlying operation and
    // thus count as confirmations.
    modifier onlymanyowners(bytes32 _operation) {
        if (confirmAndCheck(_operation)) {
            _;
        }
        // Even if required number of confirmations has't been collected yet,
        // we can't throw here - because changes to the state have to be preserved.
        // But, confirmAndCheck itself will throw in case sender is not an owner.
    }

    modifier validNumOwners(uint _numOwners) {
        require(_numOwners > 0 && _numOwners <= c_maxOwners);
        _;
    }

    modifier multiOwnedValidRequirement(uint _required, uint _numOwners) {
        require(_required > 0 && _required <= _numOwners);
        _;
    }

    modifier ownerExists(address _address) {
        require(isOwner(_address));
        _;
    }

    modifier ownerDoesNotExist(address _address) {
        require(!isOwner(_address));
        _;
    }

    modifier multiOwnedOperationIsActive(bytes32 _operation) {
        require(isOperationActive(_operation));
        _;
    }

	// METHODS

    // constructor is given number of sigs required to do protected "onlymanyowners" transactions
    // as well as the selection of addresses capable of confirming them (msg.sender is not added to the owners!).
    function multiowned(address[] _owners, uint _required)
        validNumOwners(_owners.length)
        multiOwnedValidRequirement(_required, _owners.length)
    {
        assert(c_maxOwners <= 255);

        m_numOwners = _owners.length;
        m_multiOwnedRequired = _required;

        for (uint i = 0; i < _owners.length; ++i)
        {
            address owner = _owners[i];
            // invalid and duplicate addresses are not allowed
            require(0 != owner && !isOwner(owner) /* not isOwner yet! */);

            uint currentOwnerIndex = checkOwnerIndex(i + 1 /* first slot is unused */);
            m_owners[currentOwnerIndex] = owner;
            m_ownerIndex[owner] = currentOwnerIndex;
        }

        assertOwnersAreConsistent();
    }

    /// @notice replaces an owner `_from` with another `_to`.
    /// @param _from address of owner to replace
    /// @param _to address of new owner
    // All pending operations will be canceled!
    function changeOwner(address _from, address _to)
        external
        ownerExists(_from)
        ownerDoesNotExist(_to)
        onlymanyowners(sha3(msg.data))
    {
        assertOwnersAreConsistent();

        clearPending();
        uint ownerIndex = checkOwnerIndex(m_ownerIndex[_from]);
        m_owners[ownerIndex] = _to;
        m_ownerIndex[_from] = 0;
        m_ownerIndex[_to] = ownerIndex;

        assertOwnersAreConsistent();
        OwnerChanged(_from, _to);
    }

    /// @notice adds an owner
    /// @param _owner address of new owner
    // All pending operations will be canceled!
    function addOwner(address _owner)
        external
        ownerDoesNotExist(_owner)
        validNumOwners(m_numOwners + 1)
        onlymanyowners(sha3(msg.data))
    {
        assertOwnersAreConsistent();

        clearPending();
        m_numOwners++;
        m_owners[m_numOwners] = _owner;
        m_ownerIndex[_owner] = checkOwnerIndex(m_numOwners);

        assertOwnersAreConsistent();
        OwnerAdded(_owner);
    }

    /// @notice removes an owner
    /// @param _owner address of owner to remove
    // All pending operations will be canceled!
    function removeOwner(address _owner)
        external
        ownerExists(_owner)
        validNumOwners(m_numOwners - 1)
        multiOwnedValidRequirement(m_multiOwnedRequired, m_numOwners - 1)
        onlymanyowners(sha3(msg.data))
    {
        assertOwnersAreConsistent();

        clearPending();
        uint ownerIndex = checkOwnerIndex(m_ownerIndex[_owner]);
        m_owners[ownerIndex] = 0;
        m_ownerIndex[_owner] = 0;
        //make sure m_numOwners is equal to the number of owners and always points to the last owner
        reorganizeOwners();

        assertOwnersAreConsistent();
        OwnerRemoved(_owner);
    }

    /// @notice changes the required number of owner signatures
    /// @param _newRequired new number of signatures required
    // All pending operations will be canceled!
    function changeRequirement(uint _newRequired)
        external
        multiOwnedValidRequirement(_newRequired, m_numOwners)
        onlymanyowners(sha3(msg.data))
    {
        m_multiOwnedRequired = _newRequired;
        clearPending();
        RequirementChanged(_newRequired);
    }

    /// @notice Gets an owner by 0-indexed position
    /// @param ownerIndex 0-indexed owner position
    function getOwner(uint ownerIndex) public constant returns (address) {
        return m_owners[ownerIndex + 1];
    }

    /// @notice Gets owners
    /// @return memory array of owners
    function getOwners() public constant returns (address[]) {
        address[] memory result = new address[](m_numOwners);
        for (uint i = 0; i < m_numOwners; i++)
            result[i] = getOwner(i);

        return result;
    }

    /// @notice checks if provided address is an owner address
    /// @param _addr address to check
    /// @return true if it's an owner
    function isOwner(address _addr) public constant returns (bool) {
        return m_ownerIndex[_addr] > 0;
    }

    /// @notice Tests ownership of the current caller.
    /// @return true if it's an owner
    // It's advisable to call it by new owner to make sure that the same erroneous address is not copy-pasted to
    // addOwner/changeOwner and to isOwner.
    function amIOwner() external constant onlyowner returns (bool) {
        return true;
    }

    /// @notice Revokes a prior confirmation of the given operation
    /// @param _operation operation value, typically sha3(msg.data)
    function revoke(bytes32 _operation)
        external
        multiOwnedOperationIsActive(_operation)
        onlyowner
    {
        uint ownerIndexBit = makeOwnerBitmapBit(msg.sender);
        var pending = m_multiOwnedPending[_operation];
        require(pending.ownersDone & ownerIndexBit > 0);

        assertOperationIsConsistent(_operation);

        pending.yetNeeded++;
        pending.ownersDone -= ownerIndexBit;

        assertOperationIsConsistent(_operation);
        Revoke(msg.sender, _operation);
    }

    /// @notice Checks if owner confirmed given operation
    /// @param _operation operation value, typically sha3(msg.data)
    /// @param _owner an owner address
    function hasConfirmed(bytes32 _operation, address _owner)
        external
        constant
        multiOwnedOperationIsActive(_operation)
        ownerExists(_owner)
        returns (bool)
    {
        return !(m_multiOwnedPending[_operation].ownersDone & makeOwnerBitmapBit(_owner) == 0);
    }

    // INTERNAL METHODS

    function confirmAndCheck(bytes32 _operation)
        private
        onlyowner
        returns (bool)
    {
        if (512 == m_multiOwnedPendingIndex.length)
            // In case m_multiOwnedPendingIndex grows too much we have to shrink it: otherwise at some point
            // we won't be able to do it because of block gas limit.
            // Yes, pending confirmations will be lost. Dont see any security or stability implications.
            // TODO use more graceful approach like compact or removal of clearPending completely
            clearPending();

        var pending = m_multiOwnedPending[_operation];

        // if we're not yet working on this operation, switch over and reset the confirmation status.
        if (! isOperationActive(_operation)) {
            // reset count of confirmations needed.
            pending.yetNeeded = m_multiOwnedRequired;
            // reset which owners have confirmed (none) - set our bitmap to 0.
            pending.ownersDone = 0;
            pending.index = m_multiOwnedPendingIndex.length++;
            m_multiOwnedPendingIndex[pending.index] = _operation;
            assertOperationIsConsistent(_operation);
        }

        // determine the bit to set for this owner.
        uint ownerIndexBit = makeOwnerBitmapBit(msg.sender);
        // make sure we (the message sender) haven't confirmed this operation previously.
        if (pending.ownersDone & ownerIndexBit == 0) {
            // ok - check if count is enough to go ahead.
            assert(pending.yetNeeded > 0);
            if (pending.yetNeeded == 1) {
                // enough confirmations: reset and run interior.
                delete m_multiOwnedPendingIndex[m_multiOwnedPending[_operation].index];
                delete m_multiOwnedPending[_operation];
                FinalConfirmation(msg.sender, _operation);
                return true;
            }
            else
            {
                // not enough: record that this owner in particular confirmed.
                pending.yetNeeded--;
                pending.ownersDone |= ownerIndexBit;
                assertOperationIsConsistent(_operation);
                Confirmation(msg.sender, _operation);
            }
        }
    }

    // Reclaims free slots between valid owners in m_owners.
    // TODO given that its called after each removal, it could be simplified.
    function reorganizeOwners() private {
        uint free = 1;
        while (free < m_numOwners)
        {
            // iterating to the first free slot from the beginning
            while (free < m_numOwners && m_owners[free] != 0) free++;

            // iterating to the first occupied slot from the end
            while (m_numOwners > 1 && m_owners[m_numOwners] == 0) m_numOwners--;

            // swap, if possible, so free slot is located at the end after the swap
            if (free < m_numOwners && m_owners[m_numOwners] != 0 && m_owners[free] == 0)
            {
                // owners between swapped slots should't be renumbered - that saves a lot of gas
                m_owners[free] = m_owners[m_numOwners];
                m_ownerIndex[m_owners[free]] = free;
                m_owners[m_numOwners] = 0;
            }
        }
    }

    function clearPending() private onlyowner {
        uint length = m_multiOwnedPendingIndex.length;
        for (uint i = 0; i < length; ++i) {
            if (m_multiOwnedPendingIndex[i] != 0)
                delete m_multiOwnedPending[m_multiOwnedPendingIndex[i]];
        }
        delete m_multiOwnedPendingIndex;
    }

    function checkOwnerIndex(uint ownerIndex) private constant returns (uint) {
        assert(0 != ownerIndex && ownerIndex <= c_maxOwners);
        return ownerIndex;
    }

    function makeOwnerBitmapBit(address owner) private constant returns (uint) {
        uint ownerIndex = checkOwnerIndex(m_ownerIndex[owner]);
        return 2 ** ownerIndex;
    }

    function isOperationActive(bytes32 _operation) private constant returns (bool) {
        return 0 != m_multiOwnedPending[_operation].yetNeeded;
    }


    function assertOwnersAreConsistent() private constant {
        assert(m_numOwners > 0);
        assert(m_numOwners <= c_maxOwners);
        assert(m_owners[0] == 0);
        assert(0 != m_multiOwnedRequired && m_multiOwnedRequired <= m_numOwners);
    }

    function assertOperationIsConsistent(bytes32 _operation) private constant {
        var pending = m_multiOwnedPending[_operation];
        assert(0 != pending.yetNeeded);
        assert(m_multiOwnedPendingIndex[pending.index] == _operation);
        assert(pending.yetNeeded <= m_multiOwnedRequired);
    }


   	// FIELDS

    uint constant c_maxOwners = 250;

    // the number of owners that must confirm the same operation before it is run.
    uint public m_multiOwnedRequired;


    // pointer used to find a free slot in m_owners
    uint public m_numOwners;

    // list of owners (addresses),
    // slot 0 is unused so there are no owner which index is 0.
    // TODO could we save space at the end of the array for the common case of <10 owners? and should we?
    address[256] internal m_owners;

    // index on the list of owners to allow reverse lookup: owner address => index in m_owners
    mapping(address => uint) internal m_ownerIndex;


    // the ongoing operations.
    mapping(bytes32 => MultiOwnedOperationPendingState) internal m_multiOwnedPending;
    bytes32[] internal m_multiOwnedPendingIndex;
}


/**
 * @title Contract which is owned by owners and operated by controller.
 *
 * @notice Provides a way to set up an entity (typically other contract) entitled to control actions of this contract.
 * Controller is set up by owners or during construction.
 *
 * @dev controller check is performed by onlyController modifier.
 */
contract MultiownedControlled is multiowned {

    event ControllerSet(address controller);
    event ControllerRetired(address was);


    modifier onlyController {
        require(msg.sender == m_controller);
        _;
    }


    // PUBLIC interface

    function MultiownedControlled(address[] _owners, uint _signaturesRequired, address _controller)
        multiowned(_owners, _signaturesRequired)
    {
        m_controller = _controller;
        ControllerSet(m_controller);
    }

    /// @dev sets the controller
    function setController(address _controller) external onlymanyowners(sha3(msg.data)) {
        m_controller = _controller;
        ControllerSet(m_controller);
    }

    /// @dev ability for controller to step down
    function detachController() external onlyController {
        address was = m_controller;
        m_controller = address(0);
        ControllerRetired(was);
    }


    // FIELDS

    /// @notice address of entity entitled to mint new tokens
    address public m_controller;
}


/// @title StandardToken which can be minted by another contract.
contract MintableMultiownedToken is MultiownedControlled, StandardToken {

    /// @dev parameters of an extra token emission
    struct EmissionInfo {
        // tokens created
        uint256 created;

        // totalSupply at the moment of emission (excluding created tokens)
        uint256 totalSupplyWas;
    }

    event Mint(address indexed to, uint256 amount);
    event Emission(uint256 tokensCreated, uint256 totalSupplyWas, uint256 time);
    event Dividend(address indexed to, uint256 amount);


    // PUBLIC interface

    function MintableMultiownedToken(address[] _owners, uint _signaturesRequired, address _minter)
        MultiownedControlled(_owners, _signaturesRequired, _minter)
    {
        dividendsPool = this;   // or any other special unforgeable value, actually

        // emission #0 is a dummy: because of default value 0 in m_lastAccountEmission
        m_emissions.push(EmissionInfo({created: 0, totalSupplyWas: 0}));
    }

    /// @notice Request dividends for current account.
    function requestDividends() external {
        payDividendsTo(msg.sender);
    }

    /// @notice hook on standard ERC20#transfer to pay dividends
    function transfer(address _to, uint256 _value) returns (bool) {
        payDividendsTo(msg.sender);
        payDividendsTo(_to);
        return super.transfer(_to, _value);
    }

    /// @notice hook on standard ERC20#transferFrom to pay dividends
    function transferFrom(address _from, address _to, uint256 _value) returns (bool) {
        payDividendsTo(_from);
        payDividendsTo(_to);
        return super.transferFrom(_from, _to, _value);
    }

    // Disabled: this could be undesirable because sum of (balanceOf() for each token owner) != totalSupply
    // (but: sum of (balances[owner] for each token owner) == totalSupply!).
    //
    // @notice hook on standard ERC20#balanceOf to take dividends into consideration
    // function balanceOf(address _owner) constant returns (uint256) {
    //     var (hasNewDividends, dividends) = calculateDividendsFor(_owner);
    //     return hasNewDividends ? super.balanceOf(_owner).add(dividends) : super.balanceOf(_owner);
    // }


    /// @dev mints new tokens
    function mint(address _to, uint256 _amount) external onlyController {
        require(m_externalMintingEnabled);
        payDividendsTo(_to);
        mintInternal(_to, _amount);
    }

    /// @dev disables mint(), irreversible!
    function disableMinting() external onlyController {
        require(m_externalMintingEnabled);
        m_externalMintingEnabled = false;
    }


    // INTERNAL functions

    /**
     * @notice Starts new token emission
     * @param _tokensCreated Amount of tokens to create
     * @dev Dividends are not distributed immediately as it could require billions of gas,
     * instead they are `pulled` by a holder from dividends pool account before any update to the holder account occurs.
     */
    function emissionInternal(uint256 _tokensCreated) internal {
        require(0 != _tokensCreated);
        require(_tokensCreated < totalSupply / 2);  // otherwise it looks like an error

        uint256 totalSupplyWas = totalSupply;

        m_emissions.push(EmissionInfo({created: _tokensCreated, totalSupplyWas: totalSupplyWas}));
        mintInternal(dividendsPool, _tokensCreated);

        Emission(_tokensCreated, totalSupplyWas, now);
    }

    function mintInternal(address _to, uint256 _amount) internal {
        totalSupply = totalSupply.add(_amount);
        balances[_to] = balances[_to].add(_amount);
        Transfer(this, _to, _amount);
        Mint(_to, _amount);
    }

    /// @dev adds dividends to the account _to
    function payDividendsTo(address _to) internal {
        var (hasNewDividends, dividends) = calculateDividendsFor(_to);
        if (!hasNewDividends)
            return;

        if (0 != dividends) {
            balances[dividendsPool] = balances[dividendsPool].sub(dividends);
            balances[_to] = balances[_to].add(dividends);
            Transfer(dividendsPool, _to, dividends);
        }
        m_lastAccountEmission[_to] = getLastEmissionNum();
    }

    /// @dev calculates dividends for the account _for
    /// @return (true if state has to be updated, dividend amount (could be 0!))
    function calculateDividendsFor(address _for) constant internal returns (bool hasNewDividends, uint dividends) {
        assert(_for != dividendsPool);  // no dividends for the pool!

        uint256 lastEmissionNum = getLastEmissionNum();
        uint256 lastAccountEmissionNum = m_lastAccountEmission[_for];
        assert(lastAccountEmissionNum <= lastEmissionNum);
        if (lastAccountEmissionNum == lastEmissionNum)
            return (false, 0);

        uint256 initialBalance = balances[_for];    // beware of recursion!
        if (0 == initialBalance)
            return (true, 0);

        uint256 balance = initialBalance;
        for (uint256 emissionToProcess = lastAccountEmissionNum + 1; emissionToProcess <= lastEmissionNum; emissionToProcess++) {
            EmissionInfo storage emission = m_emissions[emissionToProcess];
            assert(0 != emission.created && 0 != emission.totalSupplyWas);

            uint256 dividend = balance.mul(emission.created).div(emission.totalSupplyWas);
            Dividend(_for, dividend);

            balance = balance.add(dividend);
        }

        return (true, balance.sub(initialBalance));
    }

    function getLastEmissionNum() private constant returns (uint256) {
        return m_emissions.length - 1;
    }


    // FIELDS

    /// @notice if this true then token is still externally mintable (but this flag does't affect emissions!)
    bool public m_externalMintingEnabled = true;

    /// @dev internal address of dividends in balances mapping.
    address dividendsPool;

    /// @notice record of issued dividend emissions
    EmissionInfo[] public m_emissions;

    /// @dev for each token holder: last emission (index in m_emissions) which was processed for this holder
    mapping(address => uint256) m_lastAccountEmission;
}


/// @title Storiqa coin contract
contract STQToken is CirculatingToken, MintableMultiownedToken {


    // PUBLIC interface

    function STQToken(address[] _owners)
        MintableMultiownedToken(_owners, 2, /* minter: */ address(0))
    {
        require(3 == _owners.length);
    }

    /// @dev Allows token transfers
    function startCirculation() external onlyController {
        assert(enableCirculation());    // must be called once
    }

    /// @notice Starts new token emission
    /// @param _tokensCreatedInSTQ Amount of STQ (not STQ-wei!) to create, like 30 000 or so
    function emission(uint256 _tokensCreatedInSTQ) external onlymanyowners(sha3(msg.data)) {
        emissionInternal(_tokensCreatedInSTQ.mul(uint256(10) ** uint256(decimals)));
    }


    // FIELDS

    string public constant name = 'Storiqa Token';
    string public constant symbol = 'STQ';
    uint8 public constant decimals = 18;
}