contract UTRINToken is Ownable, StandardToken {

    using SafeMath for uint256;
    string public name;
    uint8 public decimals;
    string public symbol;
    uint256 public subscriptionPrice;
    address public stakeContract;
    address public crowdSaleContract;
    address public preSaleContract;
    address public dividendPool;
    uint256 public soldTokensUnlockTime;
    mapping (address => uint256) frozenBalances;
    mapping (address => uint256) timelock;
    
    event Burn(address indexed from, uint256 value);
    event StakeContractSet(address indexed contractAddress);

    
    constructor() {
        name = "Universal Trade Interface";
        decimals = 18;
        symbol = "UTRIN";
        
        address teamWallet = 0x41dA08f916Fc534C25FB3B388a0859b9e4A42ADa;
        address legalAndLiquidity = 0x298843E6C4Cedd1Eae5327A39847F0A170D32D26;
        address developmentFund = 0x0e70bB808E549147E3073937f13eCdc08E5d5775; 
        dividendPool = 0xd1c16226FF031Fcd961221aD25c6a43B4FB96d7E;
        
        balances[teamWallet] = 1500000 ether;                                           
        emit Transfer(address(0x0), teamWallet, (1500000 ether));                       
        
        balances[legalAndLiquidity] = 1000000 ether;                                           
        emit Transfer(address(0x0), legalAndLiquidity, (1000000 ether));
        
        balances[developmentFund] = 1500000 ether;                                    
        emit Transfer(address(0x0), developmentFund, (1500000 ether));     
        

        _totalSupply = 4000000 ether;

    }
    
    function frozenBalanceOf(address _owner) public view returns (uint256 balance) {
        return frozenBalances[_owner];
    }

    function unlockTimeOf(address _owner) public view returns (uint256 time) {
        return timelock[_owner];
    }
    
    function transfer(address _to, uint256 _value) override public  returns (bool success) {
        require(txAllowed(msg.sender, _value), "Tokens are still frozen");
        return super.transfer(_to, _value);
    }
    
    function transferFrom(address _from, address _to, uint256 _value) override public returns (bool success) { ///??
        require(txAllowed(msg.sender, _value), "Crowdsale tokens are still frozen");
        return super.transferFrom(_from, _to, _value);
    }
    
    function setStakeContract(address _contractAddress) onlyOwner public {
        stakeContract = _contractAddress;
        emit StakeContractSet(_contractAddress);
    }
    
    function setDividenPool(address _DividenPool) onlyOwner public {
        dividendPool = _DividenPool;
    }
    
        // Tokens sold by crowdsale contract will be frozen ultil crowdsale ends
    function txAllowed(address sender, uint256 amount) private returns (bool isAllowed) {
        if (timelock[sender] > block.timestamp) {
            return isBalanceFree(sender, amount);
        } else {
            if (frozenBalances[sender] > 0) frozenBalances[sender] = 0;
            return true;
        }
        
    }
    
    function isBalanceFree(address sender, uint256 amount) private view returns (bool isfree) {
        if (amount <= (balances[sender] - frozenBalances[sender])) {
            return true;
        } else {
            return false;
        }
    }
    
    function burn(uint256 _value) public onlyOwner returns (bool success) {
        require(balances[msg.sender] >= _value, "Not enough balance");
		require(_value >= 0, "Invalid amount"); 
        balances[msg.sender] = balances[msg.sender].sub(_value);
        _totalSupply = _totalSupply.sub(_value);
        emit Burn(msg.sender, _value);
        return true;
    }

    function approveStake(uint8 _timeFrame, uint256 _value) public returns (bool success) {
        require(stakeContract != address(0x0));
        allowed[msg.sender][stakeContract] = _value;
        emit Approval(msg.sender, stakeContract, _value);
        IstakeContract recipient = IstakeContract(stakeContract);
        require(recipient.createStake(msg.sender, _timeFrame, _value));
        return true;
    }
    
    function approveAndCall(address _spender, uint256 _value, bytes memory _extraData) public returns (bool success) {
        allowed[msg.sender][_spender] = _value;
        emit Approval(msg.sender, _spender, _value);
        ItokenRecipient recipient = ItokenRecipient(_spender);
        require(recipient.receiveApproval(msg.sender, _value, address(this), _extraData));
        return true;
    }
   
    function tokensSoldCrowdSale(address buyer, uint256 amount) public returns (bool success) {
        require(msg.sender == crowdSaleContract, "Error with tokensSoldCrowdSale function.");
        frozenBalances[buyer] += amount;
        if (timelock[buyer] == 0 ) timelock[buyer] = soldTokensUnlockTime;
        return super.transfer(buyer, amount);
    }
    
    function tokensSoldPreSale(address buyer, uint256 amount) public returns (bool success) {
        require(msg.sender == preSaleContract, "Error with tokensSoldPreSale function.");
        frozenBalances[buyer] += amount;
        if (timelock[buyer] == 0 ) timelock[buyer] = soldTokensUnlockTime;
        return super.transfer(buyer, amount);
    }
    
	function setPrice(uint256 newPrice) public onlyPriceManager {
		subscriptionPrice = newPrice;
	}

	function redeemTokens(uint256 amount) public{
	    require(amount > subscriptionPrice, "Insufficient Utrin tokens sent to cover your fee!");
		    address account = msg.sender;        	

        	balances[account] = balances[account].sub(amount);
        	emit Transfer(account, dividendPool, amount);
	}
	
	


    

}
function txAllowed(address sender, uint256 amount) private returns (bool isAllowed) {
        if (timelock[sender] > block.timestamp) {
            return isBalanceFree(sender, amount);
        } else {
            if (frozenBalances[sender] > 0) frozenBalances[sender] = 0;
            return true;
        }
        
    }
// Tokens sold by crowdsale contract will be frozen ultil crowdsale ends