contract SharderToken {
    using SafeMath for uint;
    string public name = "Sharder";
    string public symbol = "SS";
    uint8 public  decimals = 18;

    /// +--------------------------------------------------------------+
    /// |                 SS(Sharder) Token Issue Plan                 |
    /// +--------------------------------------------------------------+
    /// |                    First Round(Crowdsale)                    |
    /// +--------------------------------------------------------------+
    /// |     Total Sale    |      Airdrop      |  Community Reserve   |
    /// +--------------------------------------------------------------+
    /// |     250,000,000   |     50,000,000    |     50,000,000       |
    /// +--------------------------------------------------------------+
    /// | Team Reserve(50,000,000 SS): Issue in 3 years period         |
    /// +--------------------------------------------------------------+
    /// | System Reward(100,000,000 SS): Reward by Sharder Chain Auto  |
    /// +--------------------------------------------------------------+
    uint256 public totalSupply = 350000000000000000000000000;

    mapping (address => mapping (address => uint256)) public allowance;
    mapping (address => uint256) public balanceOf;

    /// The owner of contract
    address public owner;

    /// The admin account of contract
    address public admin;

    mapping (address => bool) internal accountLockup;
    mapping (address => uint) public accountLockupTime;
    mapping (address => bool) public frozenAccounts;

    mapping (address => uint) internal holderIndex;
    address[] internal holders;

    ///First round tokens whether isssued.
    bool internal firstRoundTokenIssued = false;

    /// Contract pause state
    bool public paused = true;

    /// Issue event index starting from 0.
    uint256 internal issueIndex = 0;

    // Emitted when a function is invocated without the specified preconditions.
    event InvalidState(bytes msg);

    // This notifies clients about the token issued.
    event Issue(uint issueIndex, address addr, uint ethAmount, uint tokenAmount);

    // This notifies clients about the amount to transfer
    event Transfer(address indexed from, address indexed to, uint256 value);

    // This notifies clients about the amount to approve
    event Approval(address indexed owner, address indexed spender, uint value);

    // This notifies clients about the amount burnt
    event Burn(address indexed from, uint256 value);

    // This notifies clients about the account frozen
    event FrozenFunds(address target, bool frozen);

    // This notifies clients about the pause
    event Pause();

    // This notifies clients about the unpause
    event Unpause();


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

    modifier onlyAdmin {
        require(msg.sender == owner || msg.sender == admin);
        _;
    }

    /**
     * @dev Modifier to make a function callable only when account not frozen.
     */
    modifier isNotFrozen {
        require(frozenAccounts[msg.sender] != true && now > accountLockupTime[msg.sender]);
        _;
    }

    /**
     * @dev Modifier to make a function callable only when the contract is not paused.
     */
    modifier isNotPaused() {
        require((msg.sender == owner && paused) || (msg.sender == admin && paused) || !paused);
        _;
    }

    /**
     * @dev Modifier to make a function callable only when the contract is paused.
     */
    modifier isPaused() {
        require(paused);
        _;
    }

    /**
     * Internal transfer, only can be called by this contract
     */
    function _transfer(address _from, address _to, uint _value) internal isNotFrozen isNotPaused {
        // Prevent transfer to 0x0 address. Use burn() instead
        require(_to != 0x0);
        // Check if the sender has enough
        require(balanceOf[_from] >= _value);
        // Check for overflows
        require(balanceOf[_to] + _value > balanceOf[_to]);
        // Save this for an assertion in the future
        uint previousBalances = balanceOf[_from] + balanceOf[_to];
        // Subtract from the sender
        balanceOf[_from] -= _value;
        // Add the same to the recipient
        balanceOf[_to] += _value;
        // Update holders
        addOrUpdateHolder(_from);
        addOrUpdateHolder(_to);

        Transfer(_from, _to, _value);

        // Asserts are used to use static analysis to find bugs in your code. They should never fail
        assert(balanceOf[_from] + balanceOf[_to] == previousBalances);
    }

    /**
     * @dev transfer token for a specified address
     * @param _to The address to transfer to.
     * @param _transferTokensWithDecimal The amount to be transferred.
    */
    function transfer(address _to, uint _transferTokensWithDecimal) public {
        _transfer(msg.sender, _to, _transferTokensWithDecimal);
    }

    /**
     * @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 _transferTokensWithDecimal uint the amout of tokens to be transfered
    */
    function transferFrom(address _from, address _to, uint _transferTokensWithDecimal) public isNotFrozen isNotPaused returns (bool success) {
        require(_transferTokensWithDecimal <= allowance[_from][msg.sender]);
        // Check allowance
        allowance[_from][msg.sender] -= _transferTokensWithDecimal;
        _transfer(_from, _to, _transferTokensWithDecimal);
        return true;
    }

    /**
     * Set allowance for other address
     * Allows `_spender` to spend no more than `_approveTokensWithDecimal` tokens in your behalf
     *
     * @param _spender The address authorized to spend
     * @param _approveTokensWithDecimal the max amount they can spend
     */
    function approve(address _spender, uint256 _approveTokensWithDecimal) public isNotFrozen isNotPaused returns (bool success) {
        allowance[msg.sender][_spender] = _approveTokensWithDecimal;
        Approval(msg.sender, _spender, _approveTokensWithDecimal);
        return true;
    }

    /**
     * Destroy tokens
     * Remove `_value` tokens from the system irreversibly
     * @param _burnedTokensWithDecimal the amount of reserve tokens. !!IMPORTANT is 18 DECIMALS
    */
    function burn(uint256 _burnedTokensWithDecimal) public isNotFrozen isNotPaused returns (bool success) {
        require(balanceOf[msg.sender] >= _burnedTokensWithDecimal);
        /// Check if the sender has enough
        balanceOf[msg.sender] -= _burnedTokensWithDecimal;
        /// Subtract from the sender
        totalSupply -= _burnedTokensWithDecimal;
        Burn(msg.sender, _burnedTokensWithDecimal);
        return true;
    }

    /**
     * Destroy tokens from other account
     * Remove `_value` tokens from the system irreversibly on behalf of `_from`.
     * @param _from the address of the sender
     * @param _burnedTokensWithDecimal the amount of reserve tokens. !!! IMPORTANT is 18 DECIMALS
    */
    function burnFrom(address _from, uint256 _burnedTokensWithDecimal) public isNotFrozen isNotPaused returns (bool success) {
        require(balanceOf[_from] >= _burnedTokensWithDecimal);
        /// Check if the targeted balance is enough
        require(_burnedTokensWithDecimal <= allowance[_from][msg.sender]);
        /// Check allowance
        balanceOf[_from] -= _burnedTokensWithDecimal;
        /// Subtract from the targeted balance
        allowance[_from][msg.sender] -= _burnedTokensWithDecimal;
        /// Subtract from the sender's allowance
        totalSupply -= _burnedTokensWithDecimal;
        Burn(_from, _burnedTokensWithDecimal);
        return true;
    }

    /**
     * Add holder addr into arrays.
     * @param _holderAddr the address of the holder
    */
    function addOrUpdateHolder(address _holderAddr) internal {
        // Check and add holder to array
        if (holderIndex[_holderAddr] == 0) {
            holderIndex[_holderAddr] = holders.length++;
        }
        holders[holderIndex[_holderAddr]] = _holderAddr;
    }

    /**
     * CONSTRUCTOR
     * @dev Initialize the Sharder Token v2.0
     */
    function SharderToken() public {
        owner = msg.sender;
        admin = msg.sender;
    }

    /**
     * @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 {
        require(_newOwner != address(0));
        owner = _newOwner;
    }

    /**
    * @dev Set admin account to manage contract.
    */
    function setAdmin(address _address) public onlyOwner {
        admin = _address;
    }

    /**
    * @dev Issue first round tokens to `owner` address.
    */
    function issueFirstRoundToken() public onlyOwner {
        require(!firstRoundTokenIssued);

        balanceOf[owner] = balanceOf[owner].add(totalSupply);
        Issue(issueIndex++, owner, 0, totalSupply);
        addOrUpdateHolder(owner);
        firstRoundTokenIssued = true;
    }

    /**
     * @dev Issue tokens for reserve.
     * @param _issueTokensWithDecimal the amount of reserve tokens. !!IMPORTANT is 18 DECIMALS
    */
    function issueReserveToken(uint256 _issueTokensWithDecimal) onlyOwner public {
        balanceOf[owner] = balanceOf[owner].add(_issueTokensWithDecimal);
        totalSupply = totalSupply.add(_issueTokensWithDecimal);
        Issue(issueIndex++, owner, 0, _issueTokensWithDecimal);
    }

    /**
    * @dev Frozen or unfrozen account.
    */
    function changeFrozenStatus(address _address, bool _frozenStatus) public onlyAdmin {
        frozenAccounts[_address] = _frozenStatus;
    }

    /**
    * @dev Lockup account till the date. Can't lock-up again when this account locked already.
    * 1 year = 31536000 seconds, 0.5 year = 15768000 seconds
    */
    function lockupAccount(address _address, uint _lockupSeconds) public onlyAdmin {
        require((accountLockup[_address] && now > accountLockupTime[_address]) || !accountLockup[_address]);
        // lock-up account
        accountLockupTime[_address] = now + _lockupSeconds;
        accountLockup[_address] = true;
    }

    /**
    * @dev Get the cuurent ss holder count.
    */
    function getHolderCount() public constant returns (uint _holdersCount){
        return holders.length - 1;
    }

    /*
    * @dev Get the current ss holder addresses.
    */
    function getHolders() public onlyAdmin constant returns (address[] _holders){
        return holders;
    }

    /**
     * @dev called by the owner to pause, triggers stopped state
    */
    function pause() onlyAdmin isNotPaused public {
        paused = true;
        Pause();
    }

    /**
     * @dev called by the owner to unpause, returns to normal state
    */
    function unpause() onlyAdmin isPaused public {
        paused = false;
        Unpause();
    }

    function setSymbol(string _symbol) public onlyOwner {
        symbol = _symbol;
    }

    function setName(string _name) public onlyOwner {
        name = _name;
    }

    /// @dev This default function reject anyone to purchase the SS(Sharder) token after crowdsale finished.
    function() public payable {
        revert();
    }

}
/**
 * @title Sharder Token v2.0. SS(Sharder) is upgrade from SS(Sharder Storage).
 * @author Ben - <xy@sharder.org>.
 * @dev ERC-20: https://github.com/ethereum/EIPs/blob/master/EIPS/eip-20.md
 */
function transferFrom(address _from, address _to, uint _transferTokensWithDecimal) public isNotFrozen isNotPaused returns (bool success) {
    require(_transferTokensWithDecimal <= allowance[_from][msg.sender]);
    // Check allowance
    allowance[_from][msg.sender] -= _transferTokensWithDecimal;
    _transfer(_from, _to, _transferTokensWithDecimal);
    return true;
}

/**
 * @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 _transferTokensWithDecimal uint the amout of tokens to be transfered
 */