// Vulnerability label: overflow
pragma solidity ^0.4.13;

interface IFlyDropTokenMgr {
    // Send tokens to other multi addresses in one function
    function prepare(uint256 _rand,
                     address _from,
                     address _token,
                     uint256 _value) external returns (bool);

    // Send tokens to other multi addresses in one function
    function flyDrop(address[] _destAddrs, uint256[] _values) external returns (uint256);

    // getter to determine if address has poweruser role
    function isPoweruser(address _addr) external view returns (bool);
}

interface ILockedStorage {
    // get frozen status for the _wallet address
    function frozenAccounts(address _wallet) external view returns (bool);

    // get a wallet address by the account address and the index
    function isExisted(address _wallet) external view returns (bool);

    // get a wallet name by the account address and the index
    function walletName(address _wallet) external view returns (string);

    // get the frozen amount of the account address
    function frozenAmount(address _wallet) external view returns (uint256);

    // get the balance of the account address
    function balanceOf(address _wallet) external view returns (uint256);

    // get the account address by index
    function addressByIndex(uint256 _ind) external view returns (address);

    // get the number of the locked stage of the target address
    function lockedStagesNum(address _target) external view returns (uint256);

    // get the endtime of the locked stages of an account
    function endTimeOfStage(address _target, uint _ind) external view returns (uint256);

    // get the remain unrleased tokens of the locked stages of an account
    function remainOfStage(address _target, uint _ind) external view returns (uint256);

    // get the remain unrleased tokens of the locked stages of an account
    function amountOfStage(address _target, uint _ind) external view returns (uint256);

    // get the remain releasing period end time of an account
    function releaseEndTimeOfStage(address _target, uint _ind) external view returns (uint256);

    // get the frozen amount of the account address
    function size() external view returns (uint256);

    // add one account address for that wallet
    function addAccount(address _wallet, string _name, uint256 _value) external returns (bool);

    // add a time record of one account
    function addLockedTime(address _target,
                           uint256 _value,
                           uint256 _frozenEndTime,
                           uint256 _releasePeriod) external returns (bool);

    // freeze or release the tokens that has been locked in the account address.
    function freezeTokens(address _wallet, bool _freeze, uint256 _value) external returns (bool);

    // increase balance of this account address
    function increaseBalance(address _wallet, uint256 _value) external returns (bool);

    // decrease balance of this account address
    function decreaseBalance(address _wallet, uint256 _value) external returns (bool);

    // remove account contract address from storage
    function removeAccount(address _wallet) external returns (bool);

    // remove a time records from the time records list of one account
    function removeLockedTime(address _target, uint _ind) external returns (bool);

    // set the new endtime of the released time of an account
    function changeEndTime(address _target, uint256 _ind, uint256 _newEndTime) external returns (bool);

    // set the new released period end time of an account
    function setNewReleaseEndTime(address _target, uint256 _ind, uint256 _newReleaseEndTime) external returns (bool);

    // decrease the remaining locked amount of an account
    function decreaseRemainLockedOf(address _target, uint256 _ind, uint256 _value) external returns (bool);

    // withdraw tokens from this contract
    function withdrawToken(address _token, address _to, uint256 _value) external returns (bool);
}

library SafeMath {

  /**
  * @dev Multiplies two numbers, throws on overflow.
  */
  function mul(uint256 _a, uint256 _b) internal pure returns (uint256 c) {
    // Gas optimization: this is cheaper than asserting 'a' not being zero, but the
    // benefit is lost if 'b' is also tested.
    // See: https://github.com/OpenZeppelin/openzeppelin-solidity/pull/522
    if (_a == 0) {
      return 0;
    }

    c = _a * _b;
    assert(c / _a == _b);
    return c;
  }

  /**
  * @dev Integer division of two numbers, truncating the quotient.
  */
  function div(uint256 _a, uint256 _b) internal pure 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 _a / _b;
  }

  /**
  * @dev Subtracts two numbers, throws on overflow (i.e. if subtrahend is greater than minuend).
  */
  function sub(uint256 _a, uint256 _b) internal pure returns (uint256) {
    assert(_b <= _a);
    return _a - _b;
  }

  /**
  * @dev Adds two numbers, throws on overflow.
  */
  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 OwnershipRenounced(address indexed previousOwner);
  event OwnershipTransferred(
    address indexed previousOwner,
    address indexed newOwner
  );


  /**
   * @dev The Ownable constructor sets the original `owner` of the contract to the sender
   * account.
   */
  constructor() public {
    owner = msg.sender;
  }

  /**
   * @dev Throws if called by any account other than the owner.
   */
  modifier onlyOwner() {
    require(msg.sender == owner);
    _;
  }

  /**
   * @dev Allows the current owner to relinquish control of the contract.
   * @notice Renouncing to ownership will leave the contract without an owner.
   * It will not be possible to call the functions with the `onlyOwner`
   * modifier anymore.
   */
  function renounceOwnership() public onlyOwner {
    emit OwnershipRenounced(owner);
    owner = address(0);
  }

  /**
   * @dev Allows the current owner to transfer control of the contract to a newOwner.
   * @param _newOwner The address to transfer ownership to.
   */
  function transferOwnership(address _newOwner) public onlyOwner {
    _transferOwnership(_newOwner);
  }

  /**
   * @dev Transfers control of the contract to a newOwner.
   * @param _newOwner The address to transfer ownership to.
   */
  function _transferOwnership(address _newOwner) internal {
    require(_newOwner != address(0));
    emit OwnershipTransferred(owner, _newOwner);
    owner = _newOwner;
  }
}

contract Claimable is Ownable {
  address public pendingOwner;

  /**
   * @dev Modifier throws if called by any account other than the pendingOwner.
   */
  modifier onlyPendingOwner() {
    require(msg.sender == pendingOwner);
    _;
  }

  /**
   * @dev Allows the current owner to set the pendingOwner address.
   * @param newOwner The address to transfer ownership to.
   */
  function transferOwnership(address newOwner) public onlyOwner {
    pendingOwner = newOwner;
  }

  /**
   * @dev Allows the pendingOwner address to finalize the transfer.
   */
  function claimOwnership() public onlyPendingOwner {
    emit OwnershipTransferred(owner, pendingOwner);
    owner = pendingOwner;
    pendingOwner = address(0);
  }
}

contract DelayedClaimable is Claimable {

  uint256 public end;
  uint256 public start;

  /**
   * @dev Used to specify the time period during which a pending
   * owner can claim ownership.
   * @param _start The earliest time ownership can be claimed.
   * @param _end The latest time ownership can be claimed.
   */
  function setLimits(uint256 _start, uint256 _end) public onlyOwner {
    require(_start <= _end);
    end = _end;
    start = _start;
  }

  /**
   * @dev Allows the pendingOwner address to finalize the transfer, as long as it is called within
   * the specified start and end time.
   */
  function claimOwnership() public onlyPendingOwner {
    require((block.number <= end) && (block.number >= start));
    emit OwnershipTransferred(owner, pendingOwner);
    owner = pendingOwner;
    pendingOwner = address(0);
    end = 0;
  }

}

contract OwnerContract is DelayedClaimable {
    Claimable public ownedContract;
    address public pendingOwnedOwner;
    // address internal origOwner;

    /**
     * @dev bind a contract as its owner
     *
     * @param _contract the contract address that will be binded by this Owner Contract
     */
    function bindContract(address _contract) onlyOwner public returns (bool) {
        require(_contract != address(0));
        ownedContract = Claimable(_contract);
        // origOwner = ownedContract.owner();

        // take ownership of the owned contract
        if (ownedContract.owner() != address(this)) {
            ownedContract.claimOwnership();
        }

        return true;
    }

    /**
     * @dev change the owner of the contract from this contract address to the original one.
     *
     */
    // function transferOwnershipBack() onlyOwner public {
    //     ownedContract.transferOwnership(origOwner);
    //     ownedContract = Claimable(address(0));
    //     origOwner = address(0);
    // }

    /**
     * @dev change the owner of the contract from this contract address to another one.
     *
     * @param _nextOwner the contract address that will be next Owner of the original Contract
     */
    function changeOwnershipto(address _nextOwner)  onlyOwner public {
        require(ownedContract != address(0));

        if (ownedContract.owner() != pendingOwnedOwner) {
            ownedContract.transferOwnership(_nextOwner);
            pendingOwnedOwner = _nextOwner;
            // ownedContract = Claimable(address(0));
            // origOwner = address(0);
        } else {
            // the pending owner has already taken the ownership
            ownedContract = Claimable(address(0));
            pendingOwnedOwner = address(0);
        }
    }

    /**
     * @dev to confirm the owner of the owned contract has already been transferred.
     *
     */
    function ownedOwnershipTransferred() onlyOwner public returns (bool) {
        require(ownedContract != address(0));
        if (ownedContract.owner() == pendingOwnedOwner) {
            // the pending owner has already taken the ownership
            ownedContract = Claimable(address(0));
            pendingOwnedOwner = address(0);
            return true;
        } else {
            return false;
        }
    }
}

contract ReleaseAndLockToken is OwnerContract {
    using SafeMath for uint256;

    ILockedStorage lockedStorage;
    IFlyDropTokenMgr flyDropMgr;
    // ERC20 public erc20tk;
    mapping (address => uint256) preReleaseAmounts;

    event ReleaseFunds(address indexed _target, uint256 _amount);

    /**
     * @dev bind a contract as its owner
     *
     * @param _contract the LockedStorage contract address that will be binded by this Owner Contract
     * @param _flyDropContract the flydrop contract for transfer tokens from the fixed main accounts
     */
    function initialize(address _contract, address _flyDropContract) onlyOwner public returns (bool) {
        require(_contract != address(0));
        require(_flyDropContract != address(0));

        require(super.bindContract(_contract));
        lockedStorage = ILockedStorage(_contract);
        flyDropMgr = IFlyDropTokenMgr(_flyDropContract);
        // erc20tk = ERC20(_tk);

        return true;
    }

    /**
     * judge whether we need to release some of the locked token
     *
     */
    function needRelease() public view returns (bool) {
        uint256 len = lockedStorage.size();
        uint256 i = 0;
        while (i < len) {
            address frozenAddr = lockedStorage.addressByIndex(i);
            uint256 timeRecLen = lockedStorage.lockedStagesNum(frozenAddr);
            uint256 j = 0;
            while (j < timeRecLen) {
                if (now >= lockedStorage.endTimeOfStage(frozenAddr, j)) {
                    return true;
                }

                j = j.add(1);
            }

            i = i.add(1);
        }

        return false;
    }

    /**
     * @dev judge whether we need to release the locked token of the target address
     * @param _target the owner of the amount of tokens
     *
     */
    function needReleaseFor(address _target) public view returns (bool) {
        require(_target != address(0));

        uint256 timeRecLen = lockedStorage.lockedStagesNum(_target);
        uint256 j = 0;
        while (j < timeRecLen) {
            if (now >= lockedStorage.endTimeOfStage(_target, j)) {
                return true;
            }

            j = j.add(1);
        }

        return false;
    }

    /**
     * @dev freeze the amount of tokens of an account
     *
     * @param _target the owner of some amount of tokens
     * @param _name the user name of the _target
     * @param _value the amount of the tokens
     * @param _frozenEndTime the end time of the lock period, unit is second
     * @param _releasePeriod the locking period, unit is second
     */
    function freeze(address _target, string _name, uint256 _value, uint256 _frozenEndTime, uint256 _releasePeriod) onlyOwner public returns (bool) {
        //require(_tokenAddr != address(0));
        require(_target != address(0));
        require(_value > 0);
        require(_frozenEndTime > 0);

        if (!lockedStorage.isExisted(_target)) {
            lockedStorage.addAccount(_target, _name, _value); // add new account
        }

        // each time the new locked time will be added to the backend
        require(lockedStorage.addLockedTime(_target, _value, _frozenEndTime, _releasePeriod));
        require(lockedStorage.freezeTokens(_target, true, _value));

        return true;
    }

    /**
     * @dev transfer an amount of tokens to an account, and then freeze the tokens
     *
     * @param _target the account address that will hold an amount of the tokens
     * @param _name the user name of the _target
     * @param _from the tokens holder who will transfer the tokens to target address
     * @param _tk the erc20 token need to be transferred
     * @param _value the amount of the tokens which has been transferred
     * @param _frozenEndTime the end time of the lock period, unit is second
     * @param _releasePeriod the locking period, unit is second
     */
    function transferAndFreeze(address _target,
                               string _name,
                               address _from,
                               address _tk,
                               uint256 _value,
                               uint256 _frozenEndTime,
                               uint256 _releasePeriod) onlyOwner public returns (bool) {
        require(_from != address(0));
        require(_target != address(0));
        require(_value > 0);
        require(_frozenEndTime > 0);

        // check firstly that the allowance of this contract has been set
        // require(owned.allowance(msg.sender, this) > 0);
        uint rand = now % 6 + 7; // random number between 7 to 12
        require(flyDropMgr.prepare(rand, _from, _tk, _value));

        // now we need transfer the funds before freeze them
        // require(owned.transferFrom(msg.sender, lockedStorage, _value));
        address[] memory dests = new address[](1);
        dests[0] = address(lockedStorage);
        uint256[] memory amounts = new uint256[](1);
        amounts[0] = _value;
        require(flyDropMgr.flyDrop(dests, amounts) >= 1);
        if (!lockedStorage.isExisted(_target)) {
            require(lockedStorage.addAccount(_target, _name, _value));
        } else {
            require(lockedStorage.increaseBalance(_target, _value));
        }

        // freeze the account after transfering funds
        require(freeze(_target, _name, _value, _frozenEndTime, _releasePeriod));
        return true;
    }

    /**
     * @dev transfer an amount of tokens to an account, and then freeze the tokens
     *
     * @param _target the account address that will hold an amount of the tokens
     * @param _tk the erc20 token need to be transferred
     * @param _value the amount of the tokens which has been transferred
     */
    function releaseTokens(address _target, address _tk, uint256 _value) internal {
        require(lockedStorage.withdrawToken(_tk, _target, _value));
        require(lockedStorage.freezeTokens(_target, false, _value));
        require(lockedStorage.decreaseBalance(_target, _value));
    }

    /**
     * @dev release the token which are locked for once and will be total released at once
     * after the end point of the lock period
     * @param _tk the erc20 token need to be transferred
     */
    function releaseAllOnceLock(address _tk) onlyOwner public returns (bool) {
        require(_tk != address(0));

        uint256 len = lockedStorage.size();
        uint256 i = 0;
        while (i < len) {
            address target = lockedStorage.addressByIndex(i);
            if (lockedStorage.lockedStagesNum(target) == 1
                && lockedStorage.endTimeOfStage(target, 0) == lockedStorage.releaseEndTimeOfStage(target, 0)
                && lockedStorage.endTimeOfStage(target, 0) > 0
                && now >= lockedStorage.endTimeOfStage(target, 0)) {
                uint256 releasedAmount = lockedStorage.amountOfStage(target, 0);

                // remove current release period time record
                if (!lockedStorage.removeLockedTime(target, 0)) {
                    return false;
                }

                // remove the froze account
                if (!lockedStorage.removeAccount(target)) {
                    return false;
                }

                releaseTokens(target, _tk, releasedAmount);
                emit ReleaseFunds(target, releasedAmount);
                len = len.sub(1);
            } else {
                // no account has been removed
                i = i.add(1);
            }
        }

        return true;
    }

    /**
     * @dev release the locked tokens owned by an account, which only have only one locked time
     * and don't have release stage.
     *
     * @param _target the account address that hold an amount of locked tokens
     * @param _tk the erc20 token need to be transferred
     */
    function releaseAccount(address _target, address _tk) onlyOwner public returns (bool) {
        require(_tk != address(0));

        if (!lockedStorage.isExisted(_target)) {
            return false;
        }

        if (lockedStorage.lockedStagesNum(_target) == 1
            && lockedStorage.endTimeOfStage(_target, 0) == lockedStorage.releaseEndTimeOfStage(_target, 0)
            && lockedStorage.endTimeOfStage(_target, 0) > 0
            && now >= lockedStorage.endTimeOfStage(_target, 0)) {
            uint256 releasedAmount = lockedStorage.amountOfStage(_target, 0);

            // remove current release period time record
            if (!lockedStorage.removeLockedTime(_target, 0)) {
                return false;
            }

            // remove the froze account
            if (!lockedStorage.removeAccount(_target)) {
                return false;
            }

            releaseTokens(_target, _tk, releasedAmount);
            emit ReleaseFunds(_target, releasedAmount);
        }

        // if the account are not locked for once, we will do nothing here
        return true;
    }

    /**
     * @dev release the locked tokens owned by an account with several stages
     * this need the contract get approval from the account by call approve() in the token contract
     *
     * @param _target the account address that hold an amount of locked tokens
     * @param _tk the erc20 token need to be transferred
     */
    function releaseWithStage(address _target, address _tk) onlyOwner public returns (bool) {
        require(_tk != address(0));

        address frozenAddr = _target;
        if (!lockedStorage.isExisted(frozenAddr)) {
            return false;
        }

        uint256 timeRecLen = lockedStorage.lockedStagesNum(frozenAddr);
        bool released = false;
        uint256 nowTime = now;
        for (uint256 j = 0; j < timeRecLen; released = false) {
            // iterate every time records to caculate how many tokens need to be released.
            uint256 endTime = lockedStorage.endTimeOfStage(frozenAddr, j);
            uint256 releasedEndTime = lockedStorage.releaseEndTimeOfStage(frozenAddr, j);
            uint256 amount = lockedStorage.amountOfStage(frozenAddr, j);
            uint256 remain = lockedStorage.remainOfStage(frozenAddr, j);
            if (nowTime > endTime && endTime > 0 && releasedEndTime > endTime) {
                uint256 lastReleased = amount.sub(remain);
                uint256 value = (amount * nowTime.sub(endTime) / releasedEndTime.sub(endTime)).sub(lastReleased);

                if (value > remain) {
                    value = remain;
                }
                lockedStorage.decreaseRemainLockedOf(frozenAddr, j, value);
                emit ReleaseFunds(_target, value);

                preReleaseAmounts[frozenAddr] = preReleaseAmounts[frozenAddr].add(value);
                if (lockedStorage.remainOfStage(frozenAddr, j) < 1e8) {
                    if (!lockedStorage.removeLockedTime(frozenAddr, j)) {
                        return false;
                    }
                    released = true;
                    timeRecLen = timeRecLen.sub(1);
                }
            } else if (nowTime >= endTime && endTime > 0 && releasedEndTime == endTime) {
                lockedStorage.decreaseRemainLockedOf(frozenAddr, j, remain);
                emit ReleaseFunds(frozenAddr, amount);
                preReleaseAmounts[frozenAddr] = preReleaseAmounts[frozenAddr].add(amount);
                if (!lockedStorage.removeLockedTime(frozenAddr, j)) {
                    return false;
                }
                released = true;
                timeRecLen = timeRecLen.sub(1);
            }

            if (!released) {
                j = j.add(1);
            }
        }

        // we got some amount need to be released
        if (preReleaseAmounts[frozenAddr] > 0) {
            releaseTokens(frozenAddr, _tk, preReleaseAmounts[frozenAddr]);

            // set the pre-release amount to 0 for next time
            preReleaseAmounts[frozenAddr] = 0;
        }

        // if all the frozen amounts had been released, then unlock the account finally
        if (lockedStorage.lockedStagesNum(frozenAddr) == 0) {
            if (!lockedStorage.removeAccount(frozenAddr)) {
                return false;
            }
        }

        return true;
    }

    /**
     * @dev set the new endtime of the released time of an account
     *
     * @param _target the owner of some amount of tokens
     * @param _oldEndTime the original endtime for the lock period, unit is second
     * @param _oldDuration the original duration time for the released period, unit is second
     * @param _newEndTime the new endtime for the lock period
     */
    function setNewEndtime(address _target, uint256 _oldEndTime, uint256 _oldDuration, uint256 _newEndTime) onlyOwner public returns (bool) {
        require(_target != address(0));
        require(_oldEndTime > 0 && _newEndTime > 0);

        if (!lockedStorage.isExisted(_target)) {
            return false;
        }

        uint256 timeRecLen = lockedStorage.lockedStagesNum(_target);
        uint256 j = 0;
        while (j < timeRecLen) {
            uint256 endTime = lockedStorage.endTimeOfStage(_target, j);
            uint256 releasedEndTime = lockedStorage.releaseEndTimeOfStage(_target, j);
            uint256 duration = releasedEndTime.sub(endTime);
            if (_oldEndTime == endTime && _oldDuration == duration) {
                bool res = lockedStorage.changeEndTime(_target, j, _newEndTime);
                res = lockedStorage.setNewReleaseEndTime(_target, j, _newEndTime.add(duration)) && res;
                return res;
            }

            j = j.add(1);
        }

        return false;
    }

    /**
     * @dev set the new released period length of an account
     *
     * @param _target the owner of some amount of tokens
     * @param _origEndTime the original endtime for the lock period
     * @param _origDuration the original duration time for the released period, unit is second
     * @param _newDuration the new releasing period
     */
    function setNewReleasePeriod(address _target, uint256 _origEndTime, uint256 _origDuration, uint256 _newDuration) onlyOwner public returns (bool) {
        require(_target != address(0));
        require(_origEndTime > 0);

        if (!lockedStorage.isExisted(_target)) {
            return false;
        }

        uint256 timeRecLen = lockedStorage.lockedStagesNum(_target);
        uint256 j = 0;
        while (j < timeRecLen) {
            uint256 endTime = lockedStorage.endTimeOfStage(_target, j);
            uint256 releasedEndTime = lockedStorage.releaseEndTimeOfStage(_target, j);
            if (_origEndTime == endTime && _origDuration == releasedEndTime.sub(endTime)) {
                return lockedStorage.setNewReleaseEndTime(_target, j, _origEndTime.add(_newDuration));
            }

            j = j.add(1);
        }

        return false;
    }

    /**
     * @dev get the locked stages of an account
     *
     * @param _target the owner of some amount of tokens
     */
    function getLockedStages(address _target) public view returns (uint) {
        require(_target != address(0));

        return lockedStorage.lockedStagesNum(_target);
    }

    /**
     * @dev get the endtime of the locked stages of an account
     *
     * @param _target the owner of some amount of tokens
     * @param _num the stage number of the releasing period
     */
    function getEndTimeOfStage(address _target, uint _num) public view returns (uint256) {
        require(_target != address(0));

        return lockedStorage.endTimeOfStage(_target, _num);
    }

    /**
     * @dev get the remain unrleased tokens of the locked stages of an account
     *
     * @param _target the owner of some amount of tokens
     * @param _num the stage number of the releasing period
     */
    function getRemainOfStage(address _target, uint _num) public view returns (uint256) {
        require(_target != address(0));

        return lockedStorage.remainOfStage(_target, _num);
    }

    /**
     * @dev get total remain locked tokens of an account
     *
     * @param _account the owner of some amount of tokens
     */
    function getRemainLockedOf(address _account) public view returns (uint256) {
        require(_account != address(0));

        uint256 totalRemain = 0;
        if(lockedStorage.isExisted(_account)) {
            uint256 timeRecLen = lockedStorage.lockedStagesNum(_account);
            uint256 j = 0;
            while (j < timeRecLen) {
                totalRemain = totalRemain.add(lockedStorage.remainOfStage(_account, j));
                j = j.add(1);
            }
        }

        return totalRemain;
    }

    /**
     * @dev get the remain releasing period of an account
     *
     * @param _target the owner of some amount of tokens
     * @param _num the stage number of the releasing period
     */
    function getRemainReleaseTimeOfStage(address _target, uint _num) public view returns (uint256) {
        require(_target != address(0));

        uint256 nowTime = now;
        uint256 releaseEndTime = lockedStorage.releaseEndTimeOfStage(_target, _num);

        if (releaseEndTime == 0 || releaseEndTime < nowTime) {
            return 0;
        }

        uint256 endTime = lockedStorage.endTimeOfStage(_target, _num);
        if (releaseEndTime == endTime || nowTime <= endTime ) {
            return (releaseEndTime.sub(endTime));
        }

        return (releaseEndTime.sub(nowTime));
    }

    /**
     * @dev release the locked tokens owned by a number of accounts
     *
     * @param _targets the accounts list that hold an amount of locked tokens
     * @param _tk the erc20 token need to be transferred
     */
    function releaseMultiAccounts(address[] _targets, address _tk) onlyOwner public returns (bool) {
        require(_targets.length != 0);

        bool res = false;
        uint256 i = 0;
        while (i < _targets.length) {
            res = releaseAccount(_targets[i], _tk) || res;
            i = i.add(1);
        }

        return res;
    }

    /**
     * @dev release the locked tokens owned by an account
     *
     * @param _targets the account addresses list that hold amounts of locked tokens
     * @param _tk the erc20 token need to be transferred
     */
    function releaseMultiWithStage(address[] _targets, address _tk) onlyOwner public returns (bool) {
        require(_targets.length != 0);

        bool res = false;
        uint256 i = 0;
        while (i < _targets.length) {
            res = releaseWithStage(_targets[i], _tk) || res; // as long as there is one true transaction, then the result will be true
            i = i.add(1);
        }

        return res;
    }

    /**
     * @dev convert bytes32 stream to string
     *
     * @param _b32 the bytes32 that hold a string in content
     */
    function bytes32ToString(bytes32 _b32) internal pure returns (string) {
        bytes memory bytesString = new bytes(32);
        uint charCount = 0;
        for (uint j = 0; j < 32; j++) {
            byte char = byte(bytes32(uint(_b32) * 2 ** (8 * j)));
            if (char != 0) {
                bytesString[charCount] = char;
                charCount++;
            }
        }
        bytes memory bytesStringTrimmed = new bytes(charCount);
        for (j = 0; j < charCount; j++) {
            bytesStringTrimmed[j] = bytesString[j];
        }
        return string(bytesStringTrimmed);
    }

     /**
     * @dev freeze multiple of the accounts
     *
     * @param _targets the owners of some amount of tokens
     * @param _names the user names of the _targets
     * @param _values the amounts of the tokens
     * @param _frozenEndTimes the list of the end time of the lock period, unit is second
     * @param _releasePeriods the list of the locking period, unit is second
     */
    function freezeMulti(address[] _targets, bytes32[] _names, uint256[] _values, uint256[] _frozenEndTimes, uint256[] _releasePeriods) onlyOwner public returns (bool) {
        require(_targets.length != 0);
        require(_names.length != 0);
        require(_values.length != 0);
        require(_frozenEndTimes.length != 0);
        require(_releasePeriods.length != 0);
        require(_targets.length == _names.length && _names.length == _values.length && _values.length == _frozenEndTimes.length && _frozenEndTimes.length == _releasePeriods.length);

        bool res = true;
        for (uint256 i = 0; i < _targets.length; i = i.add(1)) {
            // as long as one transaction failed, then the result will be failure
            res = freeze(_targets[i], bytes32ToString(_names[i]), _values[i], _frozenEndTimes[i], _releasePeriods[i]) && res;
        }

        return res;
    }

    /**
     * @dev transfer a list of amounts of tokens to a list of accounts, and then freeze the tokens
     *
     * @param _targets the account addresses that will hold a list of amounts of the tokens
     * @param _names the user names of the _targets
     * @param _from the tokens holder who will transfer the tokens to target address
     * @param _tk the erc20 token need to be transferred
     * @param _values the amounts of the tokens which have been transferred
     * @param _frozenEndTimes the end time list of the locked periods, unit is second
     * @param _releasePeriods the list of locking periods, unit is second
     */
    function transferAndFreezeMulti(address[] _targets, bytes32[] _names, address _from, address _tk, uint256[] _values, uint256[] _frozenEndTimes, uint256[] _releasePeriods) onlyOwner public returns (bool) {
        require(_targets.length != 0);
        require(_names.length != 0);
        require(_values.length != 0);
        require(_frozenEndTimes.length != 0);
        require(_releasePeriods.length != 0);
        require(_targets.length == _names.length && _names.length == _values.length && _values.length == _frozenEndTimes.length && _frozenEndTimes.length == _releasePeriods.length);

        bool res = true;
        for (uint256 i = 0; i < _targets.length; i = i.add(1)) {
            // as long as one transaction failed, then the result will be failure
            res = transferAndFreeze(_targets[i], bytes32ToString(_names[i]), _from, _tk, _values[i], _frozenEndTimes[i], _releasePeriods[i]) && res;
        }

        return res;
    }
}

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
  );
}