I'm trying to create a token sale for a colection. The idea is to restart the crowdsale everytime we grow funds to amplify the collection, the tokens are burnable to purchase items from the colection. The sales should have a funding cap and a time cap.

However when the time is up or the funding goal is reached I can keep sending funds to the contract and create new tokens is if the conditions i coded didn't matter.

Here's my code :

pragma solidity ^0.4.11;

import './IERC20.sol';
import './SafeMath.sol';

contract TestToken4 is IERC20 {
    
    using SafeMath for uint256;
    
    uint public _totalSupply = 0;
    uint public fundingGoal;
    uint public deadline;
    uint public amountRaised = 0;
    
    string public constant symbol = "TST4";
    string public constant name = "TestToken4";
    uint8 public constant decimals = 18;
    
    bool isEnabled;
    bool GoalReached = false;
    bool TokenSaleEnded = false;
    
    // 1 ether = 2000 tst3
    uint256 public RATE = 2000;
    
    address public owner;
    
    mapping(address => uint256) balances;
    mapping(address => mapping(address => uint256)) allowed;
    
    
    modifier isOwner() {
        require(msg.sender == owner);
        _;
    }
    
    function toggle() isOwner {
        isEnabled = !isEnabled;
    }
    
    function () payable {
        createTokens();
    }
    
    function TestToken4() {
        owner = msg.sender;
    }
    
    function createTokens() payable {
        require(
            msg.value > 0
            && isEnabled
            && !GoalReached
            && !TokenSaleEnded);
        
        uint256 tokens = msg.value.mul(RATE);
        balances[msg.sender] = balances[msg.sender].add(tokens);
        _totalSupply = _totalSupply.add(tokens);
        amountRaised = amountRaised.add(msg.value); 
        
        owner.transfer(msg.value);
    }
    
    function setCrowdsale (
        uint fundingGoalInEthers,
        uint durationInMinutes,
        uint tokensPerEth
        ) isOwner {
            fundingGoal = fundingGoalInEthers.mul(1 ether);
            deadline = now + durationInMinutes * 1 minutes;
            RATE = tokensPerEth;
        }
    
    function checkGoalReached() {
        if (amountRaised >= fundingGoal) {
            GoalReached = true;
        }
        if (now >= deadline) {
            TokenSaleEnded = true;
        }
        else {
            GoalReached = false;
            TokenSaleEnded = false;
        }
    }
    
    function totalSupply () constant returns (uint256 totalSupply) {
        return _totalSupply;
    }
    
    function balanceOf(address _owner) constant returns (uint256 balance) {
        return balances [_owner];
    }
    
    function transfer(address _to, uint256 _value) returns (bool success) {
        require(
            balances[msg.sender] >= _value
            && _value > 0
        );
        balances[msg.sender] = balances[msg.sender].sub(_value);
        balances[_to] = balances[_to].add(_value);
        Transfer(msg.sender, _to, _value);
        return true;
    }
    
    function transferFrom(address _from, address _to, uint256 _value) returns (bool success) {
        require(
            allowed[_from][msg.sender] >= _value
            && balances[_from] >= _value
            && _value > 0
        );
        balances[_from] = balances[_from].sub(_value);
        balances[_to] = balances[_to].add(_value);
        allowed[_from][msg.sender] = allowed[_from][msg.sender].sub(_value);
        Transfer(_from, _to, _value);
        return true;
    }
    
    function approve(address _spender, uint256 _value) returns (bool success) {
        allowed[msg.sender][_spender] = _value;
        Approval(msg.sender, _spender, _value);
        return true;
    }
    
    function allowance(address _owner, address _spender) constant returns (uint256 remaining) {
        return allowed[_owner][_spender];
    }
    
    function burn(uint256 _value) isOwner returns (bool success) {
        require(
            balances[msg.sender] >= _value
            && _value > 0
        );
        balances[msg.sender] = balances[msg.sender].sub(_value);
        _totalSupply = _totalSupply.sub(_value);
        Burn (msg.sender, _value);
        return true;
    } 
    
    event Transfer(address indexed _from, address indexed _to, uint256 _value);
    event Approval(address indexed _owner, address indexed _spender, uint256 _value);
    event Burn(address indexed from, uint256 value);
}