deOTC

//     █████             ███████    ███████████   █████████      
//    ░░███            ███░░░░░███ ░█░░░███░░░█  ███░░░░░███     
//  ███████   ██████  ███     ░░███░   ░███  ░  ███     ░░░      
// ███░░███  ███░░███░███      ░███    ░███    ░███              
//░███ ░███ ░███████ ░███      ░███    ░███    ░███              
//░███ ░███ ░███░░░  ░░███     ███     ░███    ░░███     ███     
//░░████████░░██████  ░░░███████░      █████    ░░█████████      
// ░░░░░░░░  ░░░░░░     ░░░░░░░       ░░░░░      ░░░░░░░░░       
                                                               
                                                               
                                                               
//  ███     ██████████      ███████    ███████████   █████████ 
//   ██████  ░░███░░░░███   ███░░░░░███ ░█░░░███░░░█  ███░░░░░███
//  ███░░░    ░███   ░░███ ███     ░░███░   ░███  ░  ███     ░░░ 
// ░░█████    ░███    ░███░███      ░███    ░███    ░███         
//  ░░░░███   ░███    ░███░███      ░███    ░███    ░███         
// ██████    ░███    ███ ░░███     ███     ░███    ░░███     ███
//░░░███     ██████████   ░░░███████░      █████    ░░█████████ 
//  ░░░     ░░░░░░░░░░      ░░░░░░░       ░░░░░      ░░░░░░░░░  


// SPDX-License-Identifier: UNLICENSED
pragma solidity ^0.8.0;

/* ---------- Minimal V2 Interfaces ---------- */
interface IUniswapV2Pair {
    function token0() external view returns (address);
    function token1() external view returns (address);
    function getReserves() external view returns (uint112 reserve0, uint112 reserve1, uint32);
}

interface IRouter {
    function WETH() external pure returns (address);
    function factory() external pure returns (address);

    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external payable;

    function swapExactETHForTokensSupportingFeeOnTransferTokens(
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external payable;

    function addLiquidityETH(
        address token,
        uint amountTokenDesired,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external payable returns (uint amountToken, uint amountETH, uint liquidity);
}

interface IFactory {
    function createPair(address tokenA, address tokenB) external returns (address pair);
    function getPair(address tokenA, address tokenB) external view returns (address pair);
    function treasury() external view returns (address treasury);
}

/* ---------- OZ IERC20 / ERC20 / Ownable ---------- */
interface IERC20 {
    event Transfer(address indexed from, address indexed to, uint256 value);
    event Approval(address indexed owner, address indexed spender, uint256 value);
    function totalSupply() external view returns (uint256);
    function balanceOf(address account) external view returns (uint256);
    function transfer(address to, 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 from, address to, uint256 amount) external returns (bool);
}
interface IERC20Metadata is IERC20 {
    function name() external view returns (string memory);
    function symbol() external view returns (string memory);
    function decimals() external view returns (uint8);
}
abstract contract Context {
    function _msgSender() internal view virtual returns (address) { return msg.sender; }
    function _msgData() internal view virtual returns (bytes calldata) { return msg.data; }
}
contract ERC20 is Context, IERC20, IERC20Metadata {
    mapping(address => uint256) private _balances;
    mapping(address => mapping(address => uint256)) private _allowances;
    uint256 private _totalSupply;
    string private _name;
    string private _symbol;

    constructor(string memory name_, string memory symbol_) { _name = name_; _symbol = symbol_; }
    function name() public view virtual override returns (string memory) { return _name; }
    function symbol() public view virtual override returns (string memory) { return _symbol; }
    function decimals() public view virtual override returns (uint8) { return 18; }
    function totalSupply() public view virtual override returns (uint256) { return _totalSupply; }
    function balanceOf(address account) public view virtual override returns (uint256) { return _balances[account]; }

    function transfer(address to, uint256 amount) public virtual override returns (bool) {
        address owner = _msgSender(); _transfer(owner, to, amount); return true;
    }
    function allowance(address owner, address spender) public view virtual override returns (uint256) {
        return _allowances[owner][spender];
    }
    function approve(address spender, uint256 amount) public virtual override returns (bool) {
        address owner = _msgSender(); _approve(owner, spender, amount); return true;
    }
    function transferFrom(address from, address to, uint256 amount) public virtual override returns (bool) {
        address spender = _msgSender(); _spendAllowance(from, spender, amount); _transfer(from, to, amount); return true;
    }
    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
        address owner = _msgSender(); _approve(owner, spender, allowance(owner, spender) + addedValue); return true;
    }
    function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
        address owner = _msgSender();
        uint256 currentAllowance = allowance(owner, spender);
        require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
        unchecked { _approve(owner, spender, currentAllowance - subtractedValue); }
        return true;
    }

    function _transfer(address from, address to, uint256 amount) internal virtual {
        require(from != address(0), "ERC20: transfer from zero"); require(to != address(0), "ERC20: transfer to zero");
        _beforeTokenTransfer(from, to, amount);
        uint256 fromBalance = _balances[from]; require(fromBalance >= amount, "ERC20: amount exceeds balance");
        unchecked { _balances[from] = fromBalance - amount; }
        _balances[to] += amount; emit Transfer(from, to, amount);
        _afterTokenTransfer(from, to, amount);
    }
    function _mint(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: mint to zero");
        _beforeTokenTransfer(address(0), account, amount);
        _totalSupply += amount; _balances[account] += amount; emit Transfer(address(0), account, amount);
        _afterTokenTransfer(address(0), account, amount);
    }
    function _burn(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: burn from zero");
        _beforeTokenTransfer(account, address(0), amount);
        uint256 bal = _balances[account]; require(bal >= amount, "ERC20: burn exceeds balance");
        unchecked { _balances[account] = bal - amount; }
        _totalSupply -= amount; emit Transfer(account, address(0), amount);
        _afterTokenTransfer(account, address(0), amount);
    }
    function _approve(address owner, address spender, uint256 amount) internal virtual {
        require(owner != address(0), "ERC20: approve from zero"); require(spender != address(0), "ERC20: approve to zero");
        _allowances[owner][spender] = amount; emit Approval(owner, spender, amount);
    }
    function _spendAllowance(address owner, address spender, uint256 amount) internal virtual {
        uint256 currentAllowance = allowance(owner, spender);
        if (currentAllowance != type(uint256).max) {
            require(currentAllowance >= amount, "ERC20: insufficient allowance");
            unchecked { _approve(owner, spender, currentAllowance - amount); }
        }
    }
    function _beforeTokenTransfer(address, address, uint256) internal virtual {}
    function _afterTokenTransfer(address, address, uint256) internal virtual {}
}
abstract contract Ownable is Context {
    address private _owner;
    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
    constructor() { _transferOwnership(_msgSender()); }
    modifier onlyOwner() { _checkOwner(); _; }
    function owner() public view virtual returns (address) { return _owner; }
    function _checkOwner() internal view virtual { require(owner() == _msgSender(), "Ownable: caller is not the owner"); }
    function renounceOwnership() public virtual onlyOwner { _transferOwnership(address(0)); }
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is zero"); _transferOwnership(newOwner);
    }
    function _transferOwnership(address newOwner) internal virtual {
        address oldOwner = _owner; _owner = newOwner; emit OwnershipTransferred(oldOwner, newOwner);
    }
}

/* =================== TOKEN =================== */
contract deOTC is Ownable, ERC20("deOTC", "DOTC") {
    /* ---- routers / pairs ---- */
    IRouter public Router;       // marketing router (DOTC->ETH)
    IRouter public BurnRouter;   // burn router (ETH->burnToken)
    address public swapPair;     // DOTC-WETH pair (for detecting buys/sells)

    /* ---- fees (in basis points; 10000 = 100%) ---- */
    uint256 public marketingFeeB;  // buy marketing bps
    uint256 public marketingFeeS;  // sell marketing bps
    uint256 public burnFee;        // shared burn bps (applies on both buy/sell)
    uint256 public swapAtAmount;   // when contract balance >= this, perform fee processing

    /* ---- fee accounting ---- */
    uint256 public tokensForMarketing;
    uint256 public tokensForBurn;

    /* ---- burn destination ---- */
    address public burnToken;   // token to buy & send to dead (if not self-burn)
    bool public isSelfBurn;    // if true, burn DOTC itself
    address public constant dead = 0x000000000000000000000000000000000000dEaD;
    bool public burnPaused;    // tracks if burning is paused
    event BurnPaused(bool paused);

    /* ---- wallets & flags ---- */
    address payable public marketingWallet;
    mapping (address => bool) public automatedMarketMakerPairs;
    mapping (address => bool) private _isExcludedFromFees;

    /* ---- reentrancy guard for swaps ---- */
    bool private inSwapAndLiquify;
    modifier lockTheSwap { inSwapAndLiquify = true; _; inSwapAndLiquify = false; }

    /* ---- Admin controls --- */
    address public tokenAdmin;
    function setTokenAdmin(address _admin) external onlyOwnerOrAdmin {
        require(_admin != address(0), "Admin cannot be zero address");
        tokenAdmin = _admin;
    }
    modifier onlyOwnerOrAdmin() {
        require(msg.sender == owner() || msg.sender == tokenAdmin, "Not owner or admin");
        _;
    }

    /* ---- events ---- */
    event ExcludeFromFees(address indexed account, bool isExcluded);
    event SetAutomatedMarketMakerPair(address indexed pair, bool indexed value);

    /* ---- burn tracking ---- */
    struct BurnStats {
        uint256 totalEthSpent;
        uint256 totalTokensBurned;
    }
    mapping(address => BurnStats) public burnHistory;
    address[] public burnTokensUsed;
    mapping(address => bool) private _burnTokenSeen;

    /* ------------ constructor ------------ */
    constructor(
        uint256 _marketingFeeBuy,
        uint256 _marketingFeeSell,
        address _router,
        address _marketingWallet,
        uint256 initialSupply
    ) {
        marketingWallet = payable(_marketingWallet);
        setMarketingFeeBuy(_marketingFeeBuy);
        setMarketingFeeSell(_marketingFeeSell);
        _isExcludedFromFees[msg.sender] = true;
        _isExcludedFromFees[address(this)] = true;
        _isExcludedFromFees[_marketingWallet] = true;
        _mint(msg.sender, initialSupply * (10**18));
        swapAtAmount = (initialSupply * (10**18)) * 10 / 1_000_000; // 0.01% of initial supply
        updateSwapRouter(_router);
        tokenAdmin = msg.sender;
    }

    /* ------------ admin: fees & wallets ------------ */
    function setMarketingFeeBuy(uint256 _newMarketingFeeBuy) public onlyOwner {
        marketingFeeB = _newMarketingFeeBuy;
        uint256 totalBuy = marketingFeeB + (burnPaused ? 0 : burnFee);
        if (_newMarketingFeeBuy > 0) require(marketingWallet != address(0), "Set marketing wallet first");
        require(totalBuy <= 2000, "Buy total fee > 20%");
    }

    function setMarketingFeeSell(uint256 _newMarketingFeeSell) public onlyOwner {
        marketingFeeS = _newMarketingFeeSell;
        uint256 totalSell = marketingFeeS + (burnPaused ? 0 : burnFee);
        if (_newMarketingFeeSell > 0) require(marketingWallet != address(0), "Set marketing wallet first");
        require(totalSell <= 2000, "Sell total fee > 20%");
    }

    function setMarketingWallet(address payable newMarketingWallet) public onlyOwner {
        if (_isExcludedFromFees[marketingWallet] == true) {
            excludeFromFees(marketingWallet, false);
        }
        marketingWallet = newMarketingWallet;
        if (_isExcludedFromFees[marketingWallet] == false) {
            excludeFromFees(marketingWallet, true);
        }
    }

    function setupBurn(address _newBurnToken, uint256 _newBurnFee, address _newBurnRouter) external onlyOwnerOrAdmin {
        setBurnToken(_newBurnToken);
        setBurnRouter(_newBurnRouter);
        setBurnFee(_newBurnFee);   
    }

    function setBurnToken(address _newBurnToken) public onlyOwnerOrAdmin {
        burnToken = _newBurnToken;
        isSelfBurn = (_newBurnToken == address(this));
    }

    function setBurnFee(uint256 _newBurnFee) public onlyOwner {
        burnFee = _newBurnFee;
        uint256 totalBuy = burnFee + marketingFeeB;
        uint256 totalSell = burnFee + marketingFeeS;
        require(totalBuy <= 2000, "Buy total fee > 20%");
        require(totalSell <= 2000, "Sell total fee > 20%");
        if (burnFee > 0 && !burnPaused) {
            require(burnToken != address(0), "Burn token not set");
            if (!isSelfBurn) require(address(BurnRouter) != address(0), "Burn router not set");
        }
    }

    function pauseBurning() external onlyOwnerOrAdmin {
        require(!burnPaused, "Burning already paused");
        burnPaused = true;
        emit BurnPaused(true);
    }

    function unpauseBurning() external onlyOwnerOrAdmin {
        require(burnPaused, "Burning not paused");
        if (burnFee > 0) {
            require(burnToken != address(0), "Burn token not set");
            if (!isSelfBurn) require(address(BurnRouter) != address(0), "Burn router not set");
        }
        burnPaused = false;
        emit BurnPaused(false);
    }

    function setSwapAtAmount(uint256 _newSwapAtAmount) external onlyOwner {
        swapAtAmount = _newSwapAtAmount;
    }

      /* ------------ manual swap & burn ------------ */
    function manualSwapNBurn() external onlyOwnerOrAdmin {
        require(!inSwapAndLiquify, "Swap already in progress");
        _swapFees();
    }

    /* ------------ router mgmt ------------ */
    function updateSwapRouter(address newAddress) public onlyOwner {
        require(newAddress != address(Router), "Router unchanged");
        Router = IRouter(newAddress);

        address weth = Router.WETH();
        address pair = IFactory(Router.factory()).getPair(address(this), weth);
        if (pair == address(0)) {
            pair = IFactory(Router.factory()).createPair(address(this), weth);
        }
        if (!automatedMarketMakerPairs[pair]) {
            _setAutomatedMarketMakerPair(pair, true);
        }
        _approve(address(this), address(Router), type(uint256).max);
        swapPair = pair;
    }

    function setBurnRouter(address _newBurnRouter) public onlyOwnerOrAdmin {
        require(_newBurnRouter != address(0), "BurnRouter=0");
        address weth;
        address factory;
        try IRouter(_newBurnRouter).WETH() returns (address w) { weth = w; } catch { revert("Not a V2 router"); }
        try IRouter(_newBurnRouter).factory() returns (address f) { factory = f; } catch { revert("Not a V2 router"); }
        require(weth != address(0) && factory != address(0), "Bad router");
        require(burnToken != address(0), "Set burnToken first");

        bool ok = _v2PairHasLiquidity(factory, weth, burnToken);
        require(ok, "No WETH-burnToken liquidity");

        BurnRouter = IRouter(_newBurnRouter);
    }

    function excludeFromFees(address account, bool excluded) public onlyOwner {
        require(_isExcludedFromFees[account] != excluded, "Already set");
        _isExcludedFromFees[account] = excluded;
        emit ExcludeFromFees(account, excluded);
    }

    function _setAutomatedMarketMakerPair(address pair, bool value) public onlyOwner {
        require(automatedMarketMakerPairs[pair] != value, "Pair already set");
        automatedMarketMakerPairs[pair] = value;
        emit SetAutomatedMarketMakerPair(pair, value);
    }

    /* ------------ fee logic ------------ */
    function _isBuy(address from, address to) internal view returns (bool) {
        return automatedMarketMakerPairs[from] && !automatedMarketMakerPairs[to];
    }

    function _isSell(address from, address to) internal view returns (bool) {
        return automatedMarketMakerPairs[to] && !automatedMarketMakerPairs[from];
    }

    function _totalFeeBpsFor(address from, address to)
        internal
        view
        returns (uint256 totalBps, uint256 mktBps, uint256 brnBps)
    {
        bool buy = _isBuy(from, to);
        bool sell = _isSell(from, to);
        if (buy) {
            mktBps = marketingFeeB; brnBps = burnPaused ? 0 : burnFee; totalBps = mktBps + brnBps;
        } else if (sell) {
            mktBps = marketingFeeS; brnBps = burnPaused ? 0 : burnFee; totalBps = mktBps + brnBps;
        } else {
            mktBps = 0; brnBps = 0; totalBps = 0;
        }
    }

    function _transfer(address from, address to, uint256 amount) internal override {
        require(from != address(0), "ERC20: transfer from zero");
        require(to != address(0), "ERC20: transfer to zero");

        if (_isExcludedFromFees[from] || _isExcludedFromFees[to]) {
            super._transfer(from, to, amount);
            return;
        }

        (uint256 totalBps, uint256 mktBps, uint256 brnBps) = _totalFeeBpsFor(from, to);

        uint256 fees;
        if (totalBps > 0) {
            fees = (amount * totalBps) / 10_000;
            if (fees > 0) {
                super._transfer(from, address(this), fees);

                if (brnBps == 0) {
                    tokensForMarketing += fees;
                } else if (mktBps == 0) {
                    tokensForBurn += fees;
                } else {
                    uint256 forMarketing = (fees * mktBps) / totalBps;
                    uint256 forBurn = fees - forMarketing;
                    tokensForMarketing += forMarketing;
                    tokensForBurn += forBurn;
                }

                amount -= fees;
            }
        }

        bool shouldSwap = _isSell(from, to) && !inSwapAndLiquify && balanceOf(address(this)) >= swapAtAmount;
        if (shouldSwap) {
            _swapFees();
        }

        super._transfer(from, to, amount);
    }

    function _swapFees() private lockTheSwap {
        uint256 contractTokenBalance = balanceOf(address(this));
        uint256 totalTokensToProcess = tokensForMarketing + tokensForBurn;
        if (contractTokenBalance == 0 || totalTokensToProcess == 0) return;

        if (isSelfBurn && tokensForBurn > 0 && !burnPaused) {
            uint256 burnTokens = (contractTokenBalance * tokensForBurn) / totalTokensToProcess;
            if (burnTokens > 0) {
                super._transfer(address(this), dead, burnTokens);
                burnHistory[burnToken].totalTokensBurned += burnTokens;
                if (!_burnTokenSeen[burnToken]) {
                    _burnTokenSeen[burnToken] = true;
                    burnTokensUsed.push(burnToken);
                }
                contractTokenBalance -= burnTokens;
            }
        }

        if (contractTokenBalance > 0) {
            address[] memory path = new address[](2);
            path[0] = address(this);
            path[1] = Router.WETH();
            _approve(address(this), address(Router), type(uint256).max);

            try Router.swapExactTokensForETHSupportingFeeOnTransferTokens(
                contractTokenBalance, 0, path, address(this), block.timestamp
            ) { } catch {
                revert("swap DOTC->ETH failed");
            }
        }

        uint256 balanceETH = address(this).balance;
        uint256 totalAfter = tokensForMarketing + (burnPaused ? 0 : tokensForBurn);
        if (balanceETH == 0 || totalAfter == 0) {
            tokensForMarketing = 0;
            tokensForBurn = 0;
            return;
        }

        uint256 ethForBurn = burnPaused ? 0 : (balanceETH * tokensForBurn) / totalAfter;
        uint256 ethForMarketing = balanceETH - ethForBurn;

        if (!isSelfBurn && tokensForBurn > 0 && ethForBurn > 0 && !burnPaused) {
            address[] memory path = new address[](2);
            path[0] = BurnRouter.WETH();
            path[1] = burnToken;

            uint256 burnTokenBefore = IERC20(burnToken).balanceOf(address(this));

            try BurnRouter.swapExactETHForTokensSupportingFeeOnTransferTokens{value: ethForBurn}(
                0, path, address(this), block.timestamp
            ) { } catch {
                revert("swap ETH->burnToken failed");
            }

            uint256 burnTokenReceived = IERC20(burnToken).balanceOf(address(this)) - burnTokenBefore;
            if (burnTokenReceived > 0) {
                IERC20(burnToken).transfer(dead, burnTokenReceived);
                burnHistory[burnToken].totalEthSpent += ethForBurn;
                burnHistory[burnToken].totalTokensBurned += burnTokenReceived;
                if (!_burnTokenSeen[burnToken]) {
                    _burnTokenSeen[burnToken] = true;
                    burnTokensUsed.push(burnToken);
                }
            }
        }

        if (ethForMarketing > 0) {
            payable(marketingWallet).transfer(ethForMarketing);
        }

        tokensForMarketing = 0;
        tokensForBurn = 0;
    }

    /* ------------ utilities ------------ */
    function _v2PairHasLiquidity(address factory, address tokenA, address tokenB)
        internal
        view
        returns (bool ok)
    {
        address pair = IFactory(factory).getPair(tokenA, tokenB);
        if (pair == address(0)) return false;
        (uint112 r0, uint112 r1, ) = IUniswapV2Pair(pair).getReserves();
        if (r0 == 0 || r1 == 0) return false;
        return true;
    }

    function isExcludedFromFees(address account) external view returns(bool) {
        return _isExcludedFromFees[account];
    }

    function currentBuyFeeBps() external view returns (uint256) {
        return marketingFeeB + (burnPaused ? 0 : burnFee);
    }

    function currentSellFeeBps() external view returns (uint256) {
        return marketingFeeS + (burnPaused ? 0 : burnFee);
    }

    struct BurnInfo {
        address token;
        uint256 ethSpent;
        uint256 tokensBurned;
    }

    function getBurnStats(uint256 page, uint256 pageSize)
    external
    view
    returns (
        BurnInfo memory current,      // the currently configured burnToken stats
        BurnInfo[] memory history,    // paginated other burn tokens
        uint256 totalPages            // based on pageSize, excluding current
    )
{
    require(page >= 1 && pageSize > 0, "bad paging");

    // 1) Current
    address curr = burnToken; // can be address(0) if not set
    current = BurnInfo({
        token: curr,
        ethSpent: burnHistory[curr].totalEthSpent,
        tokensBurned: burnHistory[curr].totalTokensBurned
    });

    // 2) History = burnTokensUsed excluding current
    uint256 n = burnTokensUsed.length;
    uint256 histCount = n;

    // If current is set and present in the list, exclude it from history
    if (curr != address(0) && _burnTokenSeen[curr]) {
        unchecked { histCount = n - 1; }
    }

    // total pages (at least 1 so UIs are simpler)
    totalPages = (histCount == 0) ? 1 : ((histCount + pageSize - 1) / pageSize);

    if (histCount == 0) {
        // nothing else in history
        history = new BurnInfo[](0);
        return (current, history, totalPages);
    }

    uint256 start = (page - 1) * pageSize;
    if (start >= histCount) {
        // out-of-range page -> empty page
        history = new BurnInfo[](0);
        return (current, history, totalPages);
    }

    uint256 remaining = histCount - start;
    uint256 len = remaining < pageSize ? remaining : pageSize;
    history = new BurnInfo[](len);

    // 3) Walk the source list, skipping `curr`, then take the window [start, start+len)
    uint256 filled = 0;
    uint256 seen = 0;
    for (uint256 i = 0; i < n && filled < len; i++) {
        address t = burnTokensUsed[i];
        if (t == curr) continue; // exclude current from history

        if (seen < start) { seen++; continue; }

        history[filled] = BurnInfo({
            token: t,
            ethSpent: burnHistory[t].totalEthSpent,
            tokensBurned: burnHistory[t].totalTokensBurned
        });
        filled++;
    }
}

    /* ------------ owner rescue ------------ */
    function removeNative() external onlyOwner {
        payable(msg.sender).transfer(address(this).balance);
    }

    function removeTokens(address _tokenAddress) external onlyOwner {
        ERC20(_tokenAddress).transfer(msg.sender, ERC20(_tokenAddress).balanceOf(address(this)));
    }

    /* ------------ receive ETH ------------ */
    receive() external payable {}
}