contract StandardToken is ERC20Interface, Pausable {
    using SafeMath for uint256;

    string public constant symbol = "AST-NET";
    string public constant name = "AllStocks Token";
    uint256 public constant decimals = 18;
    uint256 public _totalSupply = 0;

    mapping(address => uint256) public balances;
    mapping(address => mapping(address => uint256)) public allowed;

    // ------------------------------------------------------------------------
    // Constructor
    // ------------------------------------------------------------------------
    constructor() public {
        //start token in puse mode
    }


    // ------------------------------------------------------------------------
    // Total supply
    // ------------------------------------------------------------------------
    function totalSupply() public constant returns (uint256) {
        return _totalSupply.sub(balances[address(0)]);
    }


    // ------------------------------------------------------------------------
    // Get the token balance for account `tokenOwner`
    // ------------------------------------------------------------------------
    function balanceOf(address tokenOwner) public constant returns (uint256 balance) {
        return balances[tokenOwner];
    }


    // ------------------------------------------------------------------------
    // Transfer the balance from token owner's account to `to` account
    // - Owner's account must have sufficient balance to transfer
    // - 0 value transfers are allowed
    // ------------------------------------------------------------------------
    function transfer(address to, uint256 tokens) public returns (bool success) {
        //allow trading in tokens only if sale fhined or by token creator (for bounty program)
        if (msg.sender != owner)
            require(!paused);
        require(to != address(0));
        require(tokens > 0);
        require(tokens <= balances[msg.sender]);
        balances[msg.sender] = balances[msg.sender].sub(tokens);
        balances[to] = balances[to].add(tokens);
        emit Transfer(msg.sender, to, tokens);
        return true;
    }

    // ------------------------------------------------------------------------
    // Token owner can approve for `spender` to transferFrom(...) `tokens`
    // from the token owner's account
    //
    // https://github.com/ethereum/EIPs/blob/master/EIPS/eip-20-token-standard.md
    // recommends that there are no checks for the approval double-spend attack
    // as this should be implemented in user interfaces 
    // ------------------------------------------------------------------------
    function approve(address spender, uint256 tokens) public returns (bool success) {
        require(spender != address(0));
        allowed[msg.sender][spender] = tokens;
        emit Approval(msg.sender, spender, tokens);
        return true;
    }


    // ------------------------------------------------------------------------
    // Transfer `tokens` from the `from` account to the `to` account
    // 
    // The calling account must already have sufficient tokens approve(...)-d
    // for spending from the `from` account and
    // - From account must have sufficient balance to transfer
    // - Spender must have sufficient allowance to transfer
    // - 0 value transfers are not allowed
    // ------------------------------------------------------------------------
    function transferFrom(address from, address to, uint256 tokens) public returns (bool success) {
        //allow trading in token only if sale fhined 
       if (msg.sender != owner)
            require(!paused);
        require(tokens > 0);
        require(to != address(0));
        require(from != address(0));
        require(tokens <= balances[from]);
        require(tokens <= allowed[from][msg.sender]);

        balances[from] = balances[from].sub(tokens);
        allowed[from][msg.sender] = allowed[from][msg.sender].sub(tokens);
        balances[to] = balances[to].add(tokens);
        emit Transfer(from, to, tokens);
        return true;
    }


    // ------------------------------------------------------------------------
    // Returns the amount of tokens approved by the owner that can be
    // transferred to the spender's account
    // ------------------------------------------------------------------------
    function allowance(address tokenOwner, address spender) public constant returns (uint256 remaining) {
        return allowed[tokenOwner][spender];
    }
}
// ----------------------------------------------------------------------------
// ERC20 Token, with the addition of symbol, name and decimals and an
// initial fixed supply
// ----------------------------------------------------------------------------
function approve(address spender, uint256 tokens) public returns (bool success) {
        require(spender != address(0));
        allowed[msg.sender][spender] = tokens;
        emit Approval(msg.sender, spender, tokens);
        return true;
    }
// ------------------------------------------------------------------------
// Token owner can approve for `spender` to transferFrom(...) `tokens`
// from the token owner's account
//
// https://github.com/ethereum/EIPs/blob/master/EIPS/eip-20-token-standard.md
// recommends that there are no checks for the approval double-spend attack
// as this should be implemented in user interfaces 
// ------------------------------------------------------------------------