contract FourArt is StandardToken, Owned {
    string public constant name = "4ArtCoin";
    string public constant symbol = "4Art";
    uint8 public constant decimals = 18;
    uint256 public sellPrice = 0; // eth
    uint256 public buyPrice = 0; // eth
    mapping (address => bool) private SubFounders;       
    mapping (address => bool) private TeamAdviserPartner;
    
    //FounderAddress1 is main founder
    address private FounderAddress1;
    address private FounderAddress2;
    address private FounderAddress3;
    address private FounderAddress4;
    address private FounderAddress5;
    address private teamAddress;
    address private adviserAddress;
    address private partnershipAddress;
    address private bountyAddress;
    address private affiliateAddress;
    address private miscAddress;

    function FourArt(
        address _founderAddress1, 
        address _founderAddress2,
        address _founderAddress3, 
        address _founderAddress4, 
        address _founderAddress5, 
        address _teamAddress, 
        address _adviserAddress, 
        address _partnershipAddress, 
        address _bountyAddress, 
        address _affiliateAddress,
        address _miscAddress
        )  {
        totalSupply = 6500000000e18;
        //assign initial tokens for sale to contracter
        balances[msg.sender] = 4354000000e18;
        FounderAddress1 = _founderAddress1;
        FounderAddress2 = _founderAddress2;
        FounderAddress3 = _founderAddress3;
        FounderAddress4 = _founderAddress4;
        FounderAddress5 = _founderAddress5;
        teamAddress = _teamAddress;
        adviserAddress =  _adviserAddress;
        partnershipAddress = _partnershipAddress;
        bountyAddress = _bountyAddress;
        affiliateAddress = _affiliateAddress;
        miscAddress =  _miscAddress;
        
        //Assign tokens to the addresses at contract deployment
        balances[FounderAddress1] = 1390000000e18;
        balances[FounderAddress2] = 27500000e18;
        balances[FounderAddress3] = 27500000e18;
        balances[FounderAddress4] = 27500000e18;
        balances[FounderAddress5] = 27500000e18;
        balances[teamAddress] = 39000000e18;
        balances[adviserAddress] = 39000000e18;
        balances[partnershipAddress] = 39000000e18;
        balances[bountyAddress] = 65000000e18;
        balances[affiliateAddress] = 364000000e18;
        balances[miscAddress] = 100000000e18;

        //checks for tokens transfer        
        SubFounders[FounderAddress2] = true;        
        SubFounders[FounderAddress3] = true;        
        SubFounders[FounderAddress4] = true;        
        SubFounders[FounderAddress5] = true;        
        TeamAdviserPartner[teamAddress] = true;     
        TeamAdviserPartner[adviserAddress] = true;  
        TeamAdviserPartner[partnershipAddress] = true;
    }

    // Set buy and sell price of 1 token in eth.
    function setPrices(uint256 newSellPrice, uint256 newBuyPrice) onlyOwner public {
        sellPrice = newSellPrice;
        buyPrice = newBuyPrice;
    }

    // @notice Buy tokens from contract by sending ether
    function buy() payable public {
        require(now > 1543536000); // seconds since 01.01.1970 to 30.11.2018 (18:00:00 o'clock GMT)
        uint amount = msg.value.div(buyPrice);       // calculates the amount
        _transfer(owner, msg.sender, amount);   // makes the transfers
    }

    // @notice Sell `amount` tokens to contract
    function sell(uint256 amount) public {
        require(now > 1543536000); // seconds since 01.01.1970 to 30.11.2018 (18:00:00 o'clock GMT) 
        require(amount > 0);
        require(balances[msg.sender] >= amount);
        uint256 requiredBalance = amount.mul(sellPrice);
        require(this.balance >= requiredBalance);  // checks if the contract has enough ether to pay
        balances[msg.sender] -= amount;
        balances[owner] += amount;
        Transfer(msg.sender, owner, amount); 
        msg.sender.transfer(requiredBalance);    // sends ether to the seller.
    }

    function _transfer(address _from, address _to, uint _value) internal {
        // Prevent transfer to 0x0 address. Use burn() instead
        require(_to != 0x0);
        // Check if the sender has enough
        require(balances[_from] >= _value);
        // Check for overflows
        require(balances[_to] + _value > balances[_to]);
        // Subtract from the sender
        balances[_from] -= _value;
        // Add the same to the recipient
        balances[_to] += _value;
        Transfer(_from, _to, _value);
    }

    // @dev if owner wants to transfer contract ether balance to own account.
    function transferBalanceToOwner(uint256 _value) public onlyOwner {
        require(_value <= this.balance);
        owner.transfer(_value);
    }
    
    // @dev if someone wants to transfer tokens to other account.
    function transferTokens(address _to, uint256 _tokens) lockTokenTransferBeforeStage4 TeamTransferConditions(_tokens, msg.sender)   public {
        _transfer(msg.sender, _to, _tokens);
    }
    
    // @dev Transfer tokens from one address to another
    function transferFrom(address _from, address _to, uint256 _value) lockTokenTransferBeforeStage4 TeamTransferConditions(_value, _from)  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;
    }
    
    modifier lockTokenTransferBeforeStage4{
        if(msg.sender != owner){
           require(now > 1533513600); // Locking till stage 4 starting date (ICO).
        }
        _;
    }
    
    modifier TeamTransferConditions(uint256 _tokens,  address _address) {
        if(SubFounders[_address]){
            require(now > 1543536000);
            if(now > 1543536000 && now < 1569628800){
                //90% lock of total 27500000e18
                isLocked(_tokens, 24750000e18, _address);
            } 
            if(now > 1569628800 && now < 1601251200){
               //50% lock of total 27500000e18
               isLocked(_tokens, 13750000e18, _address);
            }
        }
        
        if(TeamAdviserPartner[_address]){
            require(now > 1543536000);
            if(now > 1543536000 && now < 1569628800){
                //85% lock of total 39000000e18
                isLocked(_tokens, 33150000e18, _address);
            } 
            if(now > 1569628800 && now < 1601251200){
               //60% lock of total 39000000e18
               isLocked(_tokens, 23400000e18, _address);
            }
        }
        _;
    }

    // @dev if someone wants to transfer tokens to other account.    
    function isLocked(uint256 _value,uint256 remainingTokens, address _address)  internal returns (bool) {
            uint256 remainingBalance = balances[_address].sub(_value);
            require(remainingBalance >= remainingTokens);
            return true;
    }
}
function isLocked(uint256 _value,uint256 remainingTokens, address _address)  internal returns (bool) {
            uint256 remainingBalance = balances[_address].sub(_value);
            require(remainingBalance >= remainingTokens);
            return true;
    }
// @dev if someone wants to transfer tokens to other account.    