pragma solidity ^0.4.15;

library SafeMath {
  function mul(uint256 a, uint256 b) internal constant returns (uint256) {
    if (a == 0) {
      return 0;
    }
    uint256 c = a * b;
    assert(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;
  }
}

contract ERC20Basic {
  uint256 public totalSupply;
  function balanceOf(address who) public constant 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 constant 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);
}

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) public returns (bool) {
    require(_to != address(0));
    require(_value <= balances[msg.sender]);

    // SafeMath.sub will throw if there is not enough balance.
    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) public constant returns (uint256 balance) {
    return balances[_owner];
  }

}

contract StandardToken is ERC20, BasicToken {

  mapping (address => mapping (address => uint256)) internal 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 amount of tokens to be transferred
   */
  function transferFrom(address _from, address _to, uint256 _value) public returns (bool) {
    require(_to != address(0));
    require(_value <= balances[_from]);
    require(_value <= allowed[_from][msg.sender]);

    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;
  }

  /**
   * @dev Approve the passed address to spend the specified amount of tokens on behalf of msg.sender.
   *
   * Beware that changing an allowance with this method brings the risk that someone may use both the old
   * and the new allowance by unfortunate transaction ordering. One possible solution to mitigate this
   * race condition is to first reduce the spender's allowance to 0 and set the desired value afterwards:
   * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
   * @param _spender The address which will spend the funds.
   * @param _value The amount of tokens to be spent.
   */
  function approve(address _spender, uint256 _value) public returns (bool) {
    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 specifying the amount of tokens still available for the spender.
   */
  function allowance(address _owner, address _spender) public constant returns (uint256 remaining) {
    return allowed[_owner][_spender];
  }

  /**
   * approve should be called when allowed[_spender] == 0. To increment
   * allowed value is better to use this function to avoid 2 calls (and wait until
   * the first transaction is mined)
   * From MonolithDAO Token.sol
   */
  function increaseApproval (address _spender, uint _addedValue) public returns (bool success) {
    allowed[msg.sender][_spender] = allowed[msg.sender][_spender].add(_addedValue);
    Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
    return true;
  }

  function decreaseApproval (address _spender, uint _subtractedValue) public returns (bool success) {
    uint oldValue = allowed[msg.sender][_spender];
    if (_subtractedValue > oldValue) {
      allowed[msg.sender][_spender] = 0;
    } else {
      allowed[msg.sender][_spender] = oldValue.sub(_subtractedValue);
    }
    Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
    return true;
  }

}

contract HadaCoinIco is StandardToken {
    using SafeMath for uint256;

    string public name = "HADACoin";
    string public symbol = "HADA";
    uint256 public decimals = 18;

    uint256 public totalSupply = 500000000 * (uint256(10) ** decimals);
    uint256 public totalRaised; // total ether raised (in wei)

    uint256 public startTimestamp; // timestamp after which ICO will start
    uint256 public durationSeconds = 60 * 60 * 24 * 31; // 31 Days

    uint256 public minCap; // the ICO ether goal (in wei)
    uint256 public maxCap; // the ICO ether max cap (in wei)

    /**
     * Address which will receive raised funds 
     * and owns the total supply of tokens
     */
    address public fundsWallet;

    function HadaCoinIco(
        address _fundsWallet,
        uint256 _startTimestamp,
        uint256 _minCap,
        uint256 _maxCap) {
        fundsWallet = _fundsWallet;
        startTimestamp = _startTimestamp;
        minCap = _minCap;
        maxCap = _maxCap;

        // initially assign all tokens to the fundsWallet
        balances[fundsWallet] = totalSupply;
        Transfer(0x0, fundsWallet, totalSupply);
    }

    function() isIcoOpen payable {
        totalRaised = totalRaised.add(msg.value);

        uint256 tokenAmount = calculateTokenAmount(msg.value);
        balances[fundsWallet] = balances[fundsWallet].sub(tokenAmount);
        balances[msg.sender] = balances[msg.sender].add(tokenAmount);
        Transfer(fundsWallet, msg.sender, tokenAmount);

        // immediately transfer ether to fundsWallet
        fundsWallet.transfer(msg.value);
    }

    function calculateTokenAmount(uint256 weiAmount) constant returns(uint256) {
        // standard rate: 1 ETH : 400 HADA
        uint256 tokenAmount = weiAmount.mul(400);
        if (now <= startTimestamp + 7 days) {
            // +25% bonus during first week
            return tokenAmount.mul(250).div(100);
        } else
        if (now >= startTimestamp + 7 days && now <= startTimestamp + 14 days) {
            // +20% bonus during second week
            return tokenAmount.mul(210).div(100);
        } else
        if (now >= startTimestamp + 14 days && now <= startTimestamp + 21 days) {
            // +15% bonus during third week
            return tokenAmount.mul(1725).div(1000);
        } else 
        if (now >= startTimestamp + 21 days && now <= startTimestamp + 28 days) {
            // +10% bonus during fourth week
            return tokenAmount.mul(1375).div(1000);
        } else {
            return tokenAmount;
        }
    }

    function transfer(address _to, uint _value) isIcoFinished returns (bool) {
        return super.transfer(_to, _value);
    }

    function transferFrom(address _from, address _to, uint _value) isIcoFinished returns (bool) {
        return super.transferFrom(_from, _to, _value);
    }

    modifier isIcoOpen() {
        require(now >= startTimestamp);
        require(now <= (startTimestamp + durationSeconds) || totalRaised < minCap);
        require(totalRaised <= maxCap);
        _;
    }

    modifier isIcoFinished() {
        require(now >= startTimestamp);
        require(totalRaised >= maxCap || (now >= (startTimestamp + durationSeconds) && totalRaised >= minCap));
        _;
    }
}

contract Factory {

    function createContract(
        address _fundsWallet,
        uint256 _startTimestamp,
        uint256 _minCapEth,
        uint256 _maxCapEth) returns(address created) 
    {
        return new HadaCoinIco(
            _fundsWallet,
            _startTimestamp,
            _minCapEth * 1 ether,
            _maxCapEth * 1 ether
        );
    }
}