// File: src/Token.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

import "openzeppelin-contracts/contracts/token/ERC20/utils/SafeERC20.sol";
import "openzeppelin-contracts/contracts/access/Ownable.sol";
import "./DividendPayingToken.sol";
import "./libraries/IterableMapping.sol";
import "./interfaces/IUniswapV2Pair.sol";
import "./interfaces/IUniswapV2Router.sol";
import "./interfaces/IUniswapV2Factory.sol";
import "./interfaces/ITracker.sol";
import "./TokenTracker.sol";

/**
 * Social media :
 * Website: https://www.frogs4gaza.com/
 * Telegram: https://t.me/+SKBv_yfNj2kwZjBh
 * Twitter: https://twitter.com/ftrttstokeneth
 * Instagram: https://www.instagram.com/ftrttstokeneth/
 */

contract Token is TokenTracker {
    using SafeERC20 for ERC20;

    uint256 constant BASE = 1 ether;
    uint256 constant REWARDS_FEE = 75;
    uint256 constant DEV_FEE = 25;
    uint256 constant FUND_FEE = 50;
    uint256 constant MILLE = 1000;
    uint256 constant TOTAL_FEES = REWARDS_FEE + DEV_FEE + FUND_FEE;
    address constant WETH = 0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2;
    IUniswapV2Router02 constant uniswapV2Router = IUniswapV2Router02(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D);
    uint256 public constant maxSupply = 9_000_000_000 * BASE; // Initial supply

    uint256 buyLimitTimestamp; // buy limit for the first 5 minutes
    uint256 liquidateTokensAtAmount = 900_000 * BASE; // minimum held in token contract to process fees
    uint256 public yearlyUnlock;

    address uniswapV2Pair;
    address public devAddress;
    address public fundAddress;

    bool liquidating;
    bool isBuysTaxable;
    bool public tradingEnabled; // whether the token can already be traded

    event SetAutomatedMarketMakerPair(address indexed pair, bool indexed value);

    event DevWalletUpdated(address indexed newDevWallet, address indexed oldDevWallet);

    event ExcludeFromFees(address indexed account, bool exclude);

    constructor(address _devAddress, address _fundAddress)
        DividendToken("From the River to the Sea", "FTRTTS")
        Ownable(msg.sender)
    {
        // exclude from paying fees or having max transaction amount
        _excludeFromFees(msg.sender, true);
        _excludeFromFees(_devAddress, true);
        _excludeFromFees(address(this), true);
        // excludeFromFees(_fundAddress, true);
        _excludeFromDividends(address(uniswapV2Router), true);
        _excludeFromDividends(msg.sender, true);
        _excludeFromDividends(address(this), true);
        // update the dev address
        devAddress = _devAddress;
        fundAddress = _fundAddress;
        // enable owner wallet to send tokens before presales are over.
        users[address(0)].canTransferBeforeTradingIsEnabled = true;
        users[msg.sender].canTransferBeforeTradingIsEnabled = true;

        uint256 _supply = maxSupply; // Initial supply
        _supply -= maxSupply * 10 / 100; // 10% burn
        _mint(msg.sender, _supply);

        //  Create a uniswap pair for this new token
        address _uniswapV2Pair = IUniswapV2Factory(uniswapV2Router.factory()).createPair(address(this), WETH);
        uniswapV2Pair = _uniswapV2Pair;
        _setAutomatedMarketMakerPair(uniswapV2Pair, true);
        _approve(address(this), address(uniswapV2Router), type(uint256).max);

        isBuysTaxable = true;
        yearlyUnlock = block.timestamp + 365 days;
    }

    /// @dev Distributes dividends whenever ether is paid to this contract.
    receive() external payable {
        if (msg.sender == address(uniswapV2Router)) {
            uint256 dividends = msg.value;
            uint256 devTokens = dividends * DEV_FEE / TOTAL_FEES;
            sendEth(devAddress, devTokens);
            uint256 fundTokens = dividends * FUND_FEE / TOTAL_FEES;
            sendEth(fundAddress, fundTokens);
            uint256 rewardTokens = dividends - (devTokens + fundTokens);
            _distributeDividends(rewardTokens);
        } else {
            sendEth(fundAddress, msg.value);
        }
    }

    // owner restricted
    function activate() public onlyOwner {
        require(!tradingEnabled, "Trading is already enabled");
        tradingEnabled = true;
        buyLimitTimestamp = block.timestamp + 3600;
    }

    function addTransferBeforeTrading(address account) external onlyOwner {
        users[account].canTransferBeforeTradingIsEnabled = true;
    }

    function blackList(address _user, bool value) external onlyOwner {
        require(users[_user].isBlacklisted != value, "blacklist set");
        users[_user].isBlacklisted = value;
    }

    function setAutomatedMarketMakerPair(address pair, bool value) public onlyOwner {
        require(pair != uniswapV2Pair, "Immutbale Pair");
        _setAutomatedMarketMakerPair(pair, value);
    }

    function updateDevWallet(address newDevWallet) external onlyOwner {
        require(newDevWallet != devAddress, "dev wallet set!");
        _excludeFromFees(newDevWallet, true);
        emit DevWalletUpdated(newDevWallet, devAddress);
        devAddress = newDevWallet;
    }

    function recoverERC20(address token) external onlyOwner {
        require(token != address(this), "invalid token");
        ERC20(token).safeTransfer(owner(), ERC20(token).balanceOf(address(this)));
    }

    // any unclaimed rewards will yearly be distributed 33% to dev wallet and 66% to relief fund
    function unlockUnclaimedYearly() external onlyOwner {
        require(block.timestamp > yearlyUnlock, "invalid unlock");
        yearlyUnlock = block.timestamp + 365 days;
        sendEth(devAddress, address(this).balance / 3);
        sendEth(fundAddress, address(this).balance);
    }

    function updateAmountToLiquidateAt(uint256 liquidateAmount) external onlyOwner {
        require(liquidateAmount != liquidateTokensAtAmount, "liquidate amount set!");
        liquidateTokensAtAmount = liquidateAmount;
    }

    function switchBuyTaxable(bool enabled) external onlyOwner {
        require(enabled != isBuysTaxable, "buys tax set!");
        isBuysTaxable = enabled;
    }

    function _excludeFromFees(address account, bool exclude) internal {
        require(users[account].isExcludedFromFees != exclude, "exclude fees set!");
        users[account].isExcludedFromFees = exclude;
        emit ExcludeFromFees(account, exclude);
    }

    function excludeFromFees(address account, bool enabled) external onlyOwner {
        _excludeFromFees(account, enabled);
    }

    // public functions
    function isExcludedFromFees(address account) public view returns (bool) {
        return users[account].isExcludedFromFees;
    }

    function hasDividends(address account) external view returns (bool) {
        (, int256 index,,,,,,) = _getAccount(account);
        return (index > -1);
    }

    function claimAccount(address user) public {
        uint256 amount = processAccount(payable(user));
        require(amount > 0, "0ETH");
    }

    function claim() external {
        claimAccount(msg.sender);
    }

    // private functions
    function sendEth(address account, uint256 amount) private {
        (bool success,) = account.call{value: amount}("");
        require(success, "failed ETH");
    }

    function swap(uint256 tokens) private {
        address[] memory path = new address[](2);
        path[0] = address(this);
        path[1] = WETH;

        // make the swap
        uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(
            tokens,
            0, // accept any amount of eth
            path,
            address(this),
            block.timestamp
        );
    }

    function _setAutomatedMarketMakerPair(address pair, bool value) private {
        require(users[pair].automatedMarketMakerPairs != value, "AMM pair set!");
        users[pair].automatedMarketMakerPairs = value;
        if (value) _excludeFromDividends(pair, value);
        emit SetAutomatedMarketMakerPair(pair, value);
    }

    function _update(address from, address to, uint256 amount) internal override {
        // blacklisting check
        require(!users[from].isBlacklisted && !users[to].isBlacklisted, "from or to is blacklisted");

        if (amount == 0) {
            super._update(from, to, 0);
            return;
        }

        bool tradingIsEnabled = tradingEnabled;
        bool areMeet = !liquidating && tradingIsEnabled;
        bool hasContracts = users[from].automatedMarketMakerPairs || users[to].automatedMarketMakerPairs;
        // only whitelisted addresses can make transfers before trading start.
        if (!tradingIsEnabled) {
            //turn transfer on to allow for whitelist form/mutlisend presale
            require(users[from].canTransferBeforeTradingIsEnabled, "Trading is not enabled");
        }

        if (hasContracts) {
            // excluded from fees
            bool exclusionConditions =
            (
                (users[from].isExcludedFromFees || users[to].isExcludedFromFees)
                // liquidity removing
                || (users[from].automatedMarketMakerPairs && to == address(uniswapV2Router))
                // buys
                || (!isBuysTaxable && users[from].automatedMarketMakerPairs)
            );

            bool takeFee = tradingIsEnabled && !liquidating && !exclusionConditions;
            if (takeFee) {
                uint256 fees = amount * TOTAL_FEES / MILLE;
                amount = amount - fees;

                super._update(from, address(this), fees);
            }

            if (areMeet) {
                uint256 contractTokenBalance = balanceOf(address(this));

                bool canSwap = contractTokenBalance >= liquidateTokensAtAmount;

                if (canSwap && !users[from].automatedMarketMakerPairs) {
                    liquidating = true;

                    swap(contractTokenBalance);

                    liquidating = false;
                }
            }
        }

        super._update(from, to, amount);

        uint256 fromBalance = balanceOf(from);
        uint256 toBalance = balanceOf(to);

        setBalance(from, fromBalance);
        setBalance(to, toBalance);
    }
}

// File: lib/openzeppelin-contracts/contracts/token/ERC20/utils/SafeERC20.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/utils/SafeERC20.sol)

pragma solidity ^0.8.20;

import {IERC20} from "../IERC20.sol";
import {IERC20Permit} from "../extensions/IERC20Permit.sol";
import {Address} from "../../../utils/Address.sol";

/**
 * @title SafeERC20
 * @dev Wrappers around ERC20 operations that throw on failure (when the token
 * contract returns false). Tokens that return no value (and instead revert or
 * throw on failure) are also supported, non-reverting calls are assumed to be
 * successful.
 * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
 * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
 */
library SafeERC20 {
    using Address for address;

    /**
     * @dev An operation with an ERC20 token failed.
     */
    error SafeERC20FailedOperation(address token);

    /**
     * @dev Indicates a failed `decreaseAllowance` request.
     */
    error SafeERC20FailedDecreaseAllowance(address spender, uint256 currentAllowance, uint256 requestedDecrease);

    /**
     * @dev Transfer `value` amount of `token` from the calling contract to `to`. If `token` returns no value,
     * non-reverting calls are assumed to be successful.
     */
    function safeTransfer(IERC20 token, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeCall(token.transfer, (to, value)));
    }

    /**
     * @dev Transfer `value` amount of `token` from `from` to `to`, spending the approval given by `from` to the
     * calling contract. If `token` returns no value, non-reverting calls are assumed to be successful.
     */
    function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeCall(token.transferFrom, (from, to, value)));
    }

    /**
     * @dev Increase the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
     * non-reverting calls are assumed to be successful.
     */
    function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 oldAllowance = token.allowance(address(this), spender);
        forceApprove(token, spender, oldAllowance + value);
    }

    /**
     * @dev Decrease the calling contract's allowance toward `spender` by `requestedDecrease`. If `token` returns no
     * value, non-reverting calls are assumed to be successful.
     */
    function safeDecreaseAllowance(IERC20 token, address spender, uint256 requestedDecrease) internal {
        unchecked {
            uint256 currentAllowance = token.allowance(address(this), spender);
            if (currentAllowance < requestedDecrease) {
                revert SafeERC20FailedDecreaseAllowance(spender, currentAllowance, requestedDecrease);
            }
            forceApprove(token, spender, currentAllowance - requestedDecrease);
        }
    }

    /**
     * @dev Set the calling contract's allowance toward `spender` to `value`. If `token` returns no value,
     * non-reverting calls are assumed to be successful. Meant to be used with tokens that require the approval
     * to be set to zero before setting it to a non-zero value, such as USDT.
     */
    function forceApprove(IERC20 token, address spender, uint256 value) internal {
        bytes memory approvalCall = abi.encodeCall(token.approve, (spender, value));

        if (!_callOptionalReturnBool(token, approvalCall)) {
            _callOptionalReturn(token, abi.encodeCall(token.approve, (spender, 0)));
            _callOptionalReturn(token, approvalCall);
        }
    }

    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     */
    function _callOptionalReturn(IERC20 token, bytes memory data) private {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves. We use {Address-functionCall} to perform this call, which verifies that
        // the target address contains contract code and also asserts for success in the low-level call.

        bytes memory returndata = address(token).functionCall(data);
        if (returndata.length != 0 && !abi.decode(returndata, (bool))) {
            revert SafeERC20FailedOperation(address(token));
        }
    }

    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     *
     * This is a variant of {_callOptionalReturn} that silents catches all reverts and returns a bool instead.
     */
    function _callOptionalReturnBool(IERC20 token, bytes memory data) private returns (bool) {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves. We cannot use {Address-functionCall} here since this should return false
        // and not revert is the subcall reverts.

        (bool success, bytes memory returndata) = address(token).call(data);
        return success && (returndata.length == 0 || abi.decode(returndata, (bool))) && address(token).code.length > 0;
    }
}

// File: lib/openzeppelin-contracts/contracts/access/Ownable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (access/Ownable.sol)

pragma solidity ^0.8.20;

import {Context} from "../utils/Context.sol";

/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * The initial owner is set to the address provided by the deployer. This can
 * later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
abstract contract Ownable is Context {
    address private _owner;

    /**
     * @dev The caller account is not authorized to perform an operation.
     */
    error OwnableUnauthorizedAccount(address account);

    /**
     * @dev The owner is not a valid owner account. (eg. `address(0)`)
     */
    error OwnableInvalidOwner(address owner);

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    /**
     * @dev Initializes the contract setting the address provided by the deployer as the initial owner.
     */
    constructor(address initialOwner) {
        if (initialOwner == address(0)) {
            revert OwnableInvalidOwner(address(0));
        }
        _transferOwnership(initialOwner);
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        _checkOwner();
        _;
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if the sender is not the owner.
     */
    function _checkOwner() internal view virtual {
        if (owner() != _msgSender()) {
            revert OwnableUnauthorizedAccount(_msgSender());
        }
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby disabling any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        _transferOwnership(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 {
        if (newOwner == address(0)) {
            revert OwnableInvalidOwner(address(0));
        }
        _transferOwnership(newOwner);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Internal function without access restriction.
     */
    function _transferOwnership(address newOwner) internal virtual {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}

// File: src/DividendPayingToken.sol



// // SPDX-License-Identifier: MIT

// pragma solidity ^0.8.0;

// import "openzeppelin-contracts/contracts/token/ERC20/ERC20.sol";
// import "openzeppelin-contracts/contracts/access/Ownable.sol";
// import "./libraries/SafeMath.sol";
// import "./libraries/SafeMathUint.sol";
// import "./libraries/SafeMathInt.sol";
// import "./interfaces/IDividendPayingToken.sol";
// import "./interfaces/IDividendPayingTokenOptional.sol";

// /// @title Dividend-Paying Token
// /// @author Roger Wu (https://github.com/roger-wu)
// /// @dev A mintable ERC20 token that allows anyone to pay and distribute ether
// ///  to token holders as dividends and allows token holders to withdraw their dividends.
// ///  Reference: the source code of PoWH3D: https://etherscan.io/address/0xB3775fB83F7D12A36E0475aBdD1FCA35c091efBe#code
// abstract contract DividendPayingToken is ERC20, IDividendPayingToken, IDividendPayingTokenOptional, Ownable {
//   using SafeMath for uint256;
//   using SafeMathUint for uint256;
//   using SafeMathInt for int256;

//   // With `magnitude`, we can properly distribute dividends even if the amount of received ether is small.
//   // For more discussion about choosing the value of `magnitude`,
//   //  see https://github.com/ethereum/EIPs/issues/1726#issuecomment-472352728
//   uint256 constant internal magnitude = 2**128;
//   uint256 internal magnifiedDividendPerShare;
//   uint256 internal lastAmount;
//   uint256 public totalDividendsDistributed;
//   // About dividendCorrection:
//   // If the token balance of a `_user` is never changed, the dividend of `_user` can be computed with:
//   //   `dividendOf(_user) = dividendPerShare * balanceOf(_user)`.
//   // When `balanceOf(_user)` is changed (via minting/burning/transferring tokens),
//   //   `dividendOf(_user)` should not be changed,
//   //   but the computed value of `dividendPerShare * balanceOf(_user)` is changed.
//   // To keep the `dividendOf(_user)` unchanged, we add a correction term:
//   //   `dividendOf(_user) = dividendPerShare * balanceOf(_user) + dividendCorrectionOf(_user)`,
//   //   where `dividendCorrectionOf(_user)` is updated whenever `balanceOf(_user)` is changed:
//   //   `dividendCorrectionOf(_user) = dividendPerShare * (old balanceOf(_user)) - (new balanceOf(_user))`.
//   // So now `dividendOf(_user)` returns the same value before and after `balanceOf(_user)` is changed.
//   mapping(address => int256) internal magnifiedDividendCorrections;
//   mapping(address => uint256) internal withdrawnDividends;

  

//   constructor(string memory _name, string memory _symbol) ERC20(_name, _symbol){
//   }

//   /// @dev Distributes dividends whenever ether is paid to this contract.
//   receive() external payable {
//     distributeDividends();
//   }

//   /// @notice Distributes ether to token holders as dividends.
//   /// @dev It reverts if the total supply of tokens is 0.
//   /// It emits the `DividendsDistributed` event if the amount of received ether is greater than 0.
//   /// About undistributed ether:
//   ///   In each distribution, there is a small amount of ether not distributed,
//   ///     the magnified amount of which is
//   ///     `(msg.value * magnitude) % totalSupply()`.
//   ///   With a well-chosen `magnitude`, the amount of undistributed ether
//   ///     (de-magnified) in a distribution can be less than 1 wei.
//   ///   We can actually keep track of the undistributed ether in a distribution
//   ///     and try to distribute it in the next distribution,
//   ///     but keeping track of such data on-chain costs much more than
//   ///     the saved ether, so we don't do that.
//   function distributeDividends() public override payable {
//     require(totalSupply() > 0,"dividened totalsupply error");
//     if (msg.value > 0) {
//        uint256 _magnifiedShare = magnifiedDividendPerShare.add(
//         (msg.value).mul(magnitude) / totalSupply());
//       magnifiedDividendPerShare = _magnifiedShare;
//       emit DividendsDistributed(msg.sender, msg.value);
//       uint256 _totalDistributed = totalDividendsDistributed.add(msg.value);
//       totalDividendsDistributed = _totalDistributed;
//     }
//   }

//   /// @notice Withdraws the ether distributed to the sender.
//   /// @dev It emits a `DividendWithdrawn` event if the amount of withdrawn ether is greater than 0.
//   function withdrawDividend() public virtual override {
//     _withdrawDividendOfUser(payable(msg.sender));
//   }

//   /// @notice Withdraws the ether distributed to the sender.
//   /// @dev It emits a `DividendWithdrawn` event if the amount of withdrawn ether is greater than 0.
//   function _withdrawDividendOfUser(address payable user) internal returns (uint256) {
//     uint256 _withdrawableDividend = withdrawableDividendOf(user);
//     if (_withdrawableDividend > 0) {
//       uint256 _withdrawnAmount = withdrawnDividends[user].add(_withdrawableDividend);
//       (bool success,) = user.call{value: _withdrawableDividend, gas:3000}("");
//       if(!success) {
//         return 0;
//       }
//       withdrawnDividends[user] = _withdrawnAmount;
//       return _withdrawableDividend;
//     }
//     return 0;
//   }
  
//   /// @notice View the amount of dividend in wei that an address can withdraw.
//   /// @param _owner The address of a token holder.
//   /// @return The amount of dividend in wei that `_owner` can withdraw.
//   function dividendOf(address _owner) public view override returns(uint256) {
//     uint256 _dividend = withdrawableDividendOf(_owner);
//     return _dividend;
//   }

//   /// @notice View the amount of dividend in wei that an address can withdraw.
//   /// @param _owner The address of a token holder.
//   /// @return The amount of dividend in wei that `_owner` can withdraw.
//   function withdrawableDividendOf(address _owner) public view override returns(uint256) {
//     uint256 _withdrawable = accumulativeDividendOf(_owner).sub(withdrawnDividends[_owner]);
//     return _withdrawable;
//   }

//   /// @notice View the amount of dividend in wei that an address has withdrawn.
//   /// @param _owner The address of a token holder.
//   /// @return The amount of dividend in wei that `_owner` has withdrawn.
//   function withdrawnDividendOf(address _owner) public view override returns(uint256) {
//     uint256 _withdrawn = withdrawnDividends[_owner];
//     return _withdrawn;
//   }

//   /// @notice View the amount of dividend in wei that an address has earned in total.
//   /// @dev accumulativeDividendOf(_owner) = withdrawableDividendOf(_owner) + withdrawnDividendOf(_owner)
//   /// = (magnifiedDividendPerShare * balanceOf(_owner) + magnifiedDividendCorrections[_owner]) / magnitude
//   /// @param _owner The address of a token holder.
//   /// @return The amount of dividend in wei that `_owner` has earned in total.
//   function accumulativeDividendOf(address _owner) public view override returns(uint256) {
//     uint256 _accumulative = magnifiedDividendPerShare.mul(balanceOf(_owner)).toInt256Safe()
//       .add(magnifiedDividendCorrections[_owner]).toUint256Safe() / magnitude;
//     return _accumulative;
//   }

//   /// @dev Internal function that transfer tokens from one address to another.
//   /// Update magnifiedDividendCorrections to keep dividends unchanged.
//   function _update(address from, address to, uint256 value) internal virtual override {
//     if(from == address(0)) {
//         _processMint(to, value);
//     } else if(to == address(0)) {
//         _processBurn(from, value);
//     } else {
//         require(false,"transfer inallowed");
//     }
//   }

//   /// @dev Internal function that mints tokens to an account.
//   /// Update magnifiedDividendCorrections to keep dividends unchanged.
//   /// @param account The account that will receive the created tokens.
//   /// @param value The amount that will be created.
//   function _processMint(address account, uint256 value) internal {
//     int256 _correction = magnifiedDividendCorrections[account]
//       .sub( (magnifiedDividendPerShare.mul(value)).toInt256Safe() );
//     magnifiedDividendCorrections[account] = _correction;
//   }

//   /// @dev Internal function that burns an amount of the token of a given account.
//   /// Update magnifiedDividendCorrections to keep dividends unchanged.
//   /// @param account The account whose tokens will be burnt.
//   /// @param value The amount that will be burnt.
//   function _processBurn(address account, uint256 value) internal {
//     int256 _correction = magnifiedDividendCorrections[account]
//       .add( (magnifiedDividendPerShare.mul(value)).toInt256Safe() );
//     magnifiedDividendCorrections[account] = _correction;
//   }

// //   function burn(uint256) external virtual override{
// //     require(false,"burning unallowed");  
// //   }

//   /// @dev Internal function that adjusts an address dividends shares according to the new token balance. 
//   /// @param account The account whose tokens will be proccessed .
//   /// @param newBalance The new address balance.
//   function _setBalance(address account, uint256 newBalance) internal {
//     uint256 currentBalance = balanceOf(account);
//     if(newBalance > currentBalance) {
//       uint256 mintAmount = newBalance.sub(currentBalance);
//       _mint(account, mintAmount);
//     } else if(newBalance < currentBalance) {
//       uint256 burnAmount = currentBalance.sub(newBalance);
//       _burn(account, burnAmount);
//     }
//   }
// }
// File: src/libraries/IterableMapping.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

library IterableMapping {
    // Iterable mapping from address to uint;
    struct Map {
        address[] keys;
        mapping(address => uint) values;
        mapping(address => uint) indexOf;
        mapping(address => bool) inserted;
    }

    function get(Map storage map, address key) public view returns (uint) {
        return map.values[key];
    }

    function getIndexOfKey(Map storage map, address key) public view returns (int) {
        if(!map.inserted[key]) {
            return -1;
        }
        return int(map.indexOf[key]);
    }

    function getKeyAtIndex(Map storage map, uint index) public view returns (address) {
        return map.keys[index];
    }

    function size(Map storage map) public view returns (uint) {
        return map.keys.length;
    }

    function set(Map storage map, address key, uint val) public {
        if (map.inserted[key]) {
            map.values[key] = val;
        } else {
            map.inserted[key] = true;
            map.values[key] = val;
            map.indexOf[key] = map.keys.length;
            map.keys.push(key);
        }
    }

    function remove(Map storage map, address key) public {
        if (!map.inserted[key]) {
            return;
        }

        delete map.inserted[key];
        delete map.values[key];

        uint index = map.indexOf[key];
        uint lastIndex = map.keys.length - 1;
        address lastKey = map.keys[lastIndex];

        map.indexOf[lastKey] = index;
        delete map.indexOf[key];

        map.keys[index] = lastKey;
        map.keys.pop();
    }
}
// File: src/interfaces/IUniswapV2Pair.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

interface IUniswapV2Pair {
    event Approval(address indexed owner, address indexed spender, uint value);
    event Transfer(address indexed from, address indexed to, uint value);

    function name() external pure returns (string memory);
    function symbol() external pure returns (string memory);
    function decimals() external pure returns (uint8);
    function totalSupply() external view returns (uint);
    function balanceOf(address owner) external view returns (uint);
    function allowance(address owner, address spender) external view returns (uint);

    function approve(address spender, uint value) external returns (bool);
    function transfer(address to, uint value) external returns (bool);
    function transferFrom(address from, address to, uint value) external returns (bool);

    function DOMAIN_SEPARATOR() external view returns (bytes32);
    function PERMIT_TYPEHASH() external pure returns (bytes32);
    function nonces(address owner) external view returns (uint);

    function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external;

    event Mint(address indexed sender, uint amount0, uint amount1);
    event Burn(address indexed sender, uint amount0, uint amount1, address indexed to);
    event Swap(
        address indexed sender,
        uint amount0In,
        uint amount1In,
        uint amount0Out,
        uint amount1Out,
        address indexed to
    );
    event Sync(uint112 reserve0, uint112 reserve1);

    function MINIMUM_LIQUIDITY() external pure returns (uint);
    function factory() external view returns (address);
    function token0() external view returns (address);
    function token1() external view returns (address);
    function getReserves() external view returns (uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast);
    function price0CumulativeLast() external view returns (uint);
    function price1CumulativeLast() external view returns (uint);
    function kLast() external view returns (uint);

    function mint(address to) external returns (uint liquidity);
    function burn(address to) external returns (uint amount0, uint amount1);
    function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external;
    function skim(address to) external;
    function sync() external;

    function initialize(address, address) external;
}
// File: src/interfaces/IUniswapV2Router.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

interface IUniswapV2Router01 {
    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 removeLiquidity(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB);
    function removeLiquidityETH(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountToken, uint amountETH);
    function removeLiquidityWithPermit(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountA, uint amountB);
    function removeLiquidityETHWithPermit(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountToken, uint amountETH);
    function swapExactTokensForTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
    function swapTokensForExactTokens(
        uint amountOut,
        uint amountInMax,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
    function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        payable
        returns (uint[] memory amounts);
    function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline)
        external
        returns (uint[] memory amounts);
    function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        returns (uint[] memory amounts);
    function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline)
        external
        payable
        returns (uint[] memory amounts);

    function quote(uint amountA, uint reserveA, uint reserveB) external pure returns (uint amountB);
    function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) external pure returns (uint amountOut);
    function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) external pure returns (uint amountIn);
    function getAmountsOut(uint amountIn, address[] calldata path) external view returns (uint[] memory amounts);
    function getAmountsIn(uint amountOut, address[] calldata path) external view returns (uint[] memory amounts);
}



// pragma solidity >=0.6.2;

interface IUniswapV2Router02 is IUniswapV2Router01 {
    function removeLiquidityETHSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountETH);
    function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountETH);
    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;
}
// File: src/interfaces/IUniswapV2Factory.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

interface IUniswapV2Factory {
    event PairCreated(address indexed token0, address indexed token1, address pair, uint);

    function feeTo() external view returns (address);
    function feeToSetter() external view returns (address);

    function getPair(address tokenA, address tokenB) external view returns (address pair);
    function allPairs(uint) external view returns (address pair);
    function allPairsLength() external view returns (uint);

    function createPair(address tokenA, address tokenB) external returns (address pair);

    function setFeeTo(address) external;
    function setFeeToSetter(address) external;
}
// File: src/interfaces/ITracker.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;
interface ITracker{
    // view functions
    function claimWait() external view returns(uint256);
    function owner() external view returns (address);
    function isExcludedFromDividends(address account) external view returns(bool);
    function totalDividendsDistributed() external view returns(uint256);
    function withdrawableDividendOf(address account) external view returns(uint256);
    function getLastProcessedIndex() external view returns(uint256);
    function getNumberOfTokenHolders() external view returns(uint256);
    function getAccount(address _account)
        external view returns (
            address account,
            int256 index,
            int256 iterationsUntilProcessed,
            uint256 withdrawableDividends,
            uint256 totalDividends,
            uint256 lastClaimTime,
            uint256 nextClaimTime,
            uint256 secondsUntilAutoClaimAvailable);
    function getAccountAtIndex(uint256 _index)
        external view returns (
            address account,
            int256 index,
            int256 iterationsUntilProcessed,
            uint256 withdrawableDividends,
            uint256 totalDividends,
            uint256 lastClaimTime,
            uint256 nextClaimTime,
            uint256 secondsUntilAutoClaimAvailable);
    // state functions
    function excludeFromDividends(address account, bool exclude) external;
    function updateClaimWait(uint256 newClaimWait) external;
    function setBalance(address payable account, uint256 newBalance) external;
    function process(uint256 gas) external returns (uint256, uint256, uint256);
    function processAccount(address payable account) external;
}
// File: src/TokenTracker.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

import "./DividendToken.sol";
import "./libraries/IterableMapping.sol";

abstract contract TokenTracker is DividendToken {
    using SafeMathInt for int256;
    using IterableMapping for IterableMapping.Map;

    struct User {
        bool isExcludedFromDividends;
        bool isExcludedFromFees;
        bool canTransferBeforeTradingIsEnabled;
        bool automatedMarketMakerPairs;
        bool isBlacklisted;
        uint64 lastClaimTimes;
    }

    // minimum tokens to be eligibile for dividends
    uint256 public constant minimumTokenBalanceForDividends = 9_000_000 ether;
    IterableMapping.Map private tokenHoldersMap;
    uint256 public lastProcessedIndex;
    uint256 public claimWait = 3600;

    mapping(address => User) internal users;

    event ExcludeFromDividends(address indexed account, bool exclude);
    event ClaimWaitUpdated(uint256 indexed newValue, uint256 indexed oldValue);
    event Claim(address indexed account, uint256 amount);

    // internal functions
    function _dividendShare(address _account) internal view override returns (uint256 _share) {
        _share = tokenHoldersMap.get(_account);
    }
    
    function _getAccount(address _account)
        internal
        view
        returns (
            address account,
            int256 index,
            int256 iterationsUntilProcessed,
            uint256 withdrawableDividends,
            uint256 totalDividends,
            uint256 lastClaimTime,
            uint256 nextClaimTime,
            uint256 secondsUntilAutoClaimAvailable
        )
    {
        account = _account;

        index = tokenHoldersMap.getIndexOfKey(account);

        iterationsUntilProcessed = -1;

        if (index >= 0) {
            if (uint256(index) > lastProcessedIndex) {
                iterationsUntilProcessed = index - int256(lastProcessedIndex);
            } else {
                uint256 processesUntilEndOfArray = tokenHoldersMap.keys.length > lastProcessedIndex
                    ? tokenHoldersMap.keys.length - lastProcessedIndex
                    : 0;

                iterationsUntilProcessed = index + int256(processesUntilEndOfArray);
            }
        }

        withdrawableDividends = withdrawableDividendOf(account);
        totalDividends = accumulativeDividendOf(account);

        lastClaimTime = users[account].lastClaimTimes;

        nextClaimTime = lastClaimTime > 0 ? lastClaimTime + claimWait : 0;

        secondsUntilAutoClaimAvailable = nextClaimTime > block.timestamp ? nextClaimTime - block.timestamp : 0;
    }

    function canAutoClaim(uint256 lastClaimTime) private view returns (bool) {
        if (lastClaimTime > block.timestamp) {
            return false;
        }

        return block.timestamp - lastClaimTime >= claimWait;
    }

    function _excludeFromDividends(address account, bool exclude) internal {
        require(users[account].isExcludedFromDividends != exclude, "already has been set!");
        users[account].isExcludedFromDividends = exclude;
        uint256 bal = balanceOf(account);
        if (exclude) {
            _setBalance(account, 0);
            tokenHoldersMap.remove(account);
        } else {
            _setBalance(account, bal);
            tokenHoldersMap.set(account, bal);
        }

        emit ExcludeFromDividends(account, exclude);
    }

    function setBalance(address account, uint256 newBalance) internal {
        if (users[account].isExcludedFromDividends) {
            return;
        }
        if (newBalance >= minimumTokenBalanceForDividends) {
            _setBalance(account, newBalance);
            tokenHoldersMap.set(account, newBalance);
        } else {
            _setBalance(account, 0);
            tokenHoldersMap.remove(account);
        }

        _processAccount(payable(account));
    }

    function processAccount(address payable account) internal returns (uint256 amount) {
        amount = _withdrawDividendOfUser(account);
        emit Claim(account, amount);
    }

    function _processAccount(address payable account) private returns (bool) {
        uint256 amount = _withdrawDividendOfUser(account);

        if (amount > 0) {
            // safe casting
            users[account].lastClaimTimes = uint64(block.timestamp);
            return true;
        }

        return false;
    }

    // owner restricted
    function excludeFromDividends(address account, bool exclude) external onlyOwner {
        _excludeFromDividends(account, exclude);
    }

    function updateClaimWait(uint256 newClaimWait) external onlyOwner {
        require(newClaimWait >= 1800 && newClaimWait <= 86400, "must be updated 1 to 24 hours");
        require(newClaimWait != claimWait, "same claimWait value");
        emit ClaimWaitUpdated(newClaimWait, claimWait);
        claimWait = newClaimWait;
    }

    // public functions
    function getLastProcessedIndex() external view returns (uint256) {
        return lastProcessedIndex;
    }

    function getNumberOfTokenHolders() external view returns (uint256) {
        return tokenHoldersMap.keys.length;
    }

    function getAccount(address account)
        external
        view
        returns (address, int256, int256, uint256, uint256, uint256, uint256, uint256)
    {
        return _getAccount(account);
    }

    function getAccountAtIndex(uint256 index)
        public
        view
        returns (address, int256, int256, uint256, uint256, uint256, uint256, uint256)
    {
        if (index >= tokenHoldersMap.size()) {
            return (0x0000000000000000000000000000000000000000, -1, -1, 0, 0, 0, 0, 0);
        }

        address account = tokenHoldersMap.getKeyAtIndex(index);

        return _getAccount(account);
    }

    function process(uint256 gas) public returns (uint256, uint256, uint256) {
        uint256 numberOfTokenHolders = tokenHoldersMap.keys.length;

        if (numberOfTokenHolders == 0) {
            return (0, 0, lastProcessedIndex);
        }

        uint256 _lastProcessedIndex = lastProcessedIndex;

        uint256 gasUsed = 0;

        uint256 gasLeft = gasleft();

        uint256 iterations = 0;
        uint256 claims = 0;

        while (gasUsed < gas && iterations < numberOfTokenHolders) {
            _lastProcessedIndex++;

            if (_lastProcessedIndex >= tokenHoldersMap.keys.length) {
                _lastProcessedIndex = 0;
            }

            address account = tokenHoldersMap.keys[_lastProcessedIndex];

            if (canAutoClaim(users[account].lastClaimTimes)) {
                if (_processAccount(payable(account))) {
                    claims++;
                }
            }

            iterations++;

            uint256 newGasLeft = gasleft();

            if (gasLeft > newGasLeft) {
                gasUsed = gasUsed + (gasLeft - newGasLeft);
            }

            gasLeft = newGasLeft;
        }

        lastProcessedIndex = _lastProcessedIndex;

        return (iterations, claims, lastProcessedIndex);
    }
}

// File: lib/openzeppelin-contracts/contracts/token/ERC20/IERC20.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/IERC20.sol)

pragma solidity ^0.8.20;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @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);

    /**
     * @dev Returns the value of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns the value of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);

    /**
     * @dev Moves a `value` amount of tokens from the caller's account to `to`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address to, uint256 value) 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.
     */
    function allowance(address owner, address spender) external view returns (uint256);

    /**
     * @dev Sets a `value` amount of tokens 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 value) external returns (bool);

    /**
     * @dev Moves a `value` amount of tokens from `from` to `to` using the
     * allowance mechanism. `value` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address from, address to, uint256 value) external returns (bool);
}

// File: lib/openzeppelin-contracts/contracts/token/ERC20/extensions/IERC20Permit.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/extensions/IERC20Permit.sol)

pragma solidity ^0.8.20;

/**
 * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
 * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
 *
 * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
 * presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
 * need to send a transaction, and thus is not required to hold Ether at all.
 *
 * ==== Security Considerations
 *
 * There are two important considerations concerning the use of `permit`. The first is that a valid permit signature
 * expresses an allowance, and it should not be assumed to convey additional meaning. In particular, it should not be
 * considered as an intention to spend the allowance in any specific way. The second is that because permits have
 * built-in replay protection and can be submitted by anyone, they can be frontrun. A protocol that uses permits should
 * take this into consideration and allow a `permit` call to fail. Combining these two aspects, a pattern that may be
 * generally recommended is:
 *
 * ```solidity
 * function doThingWithPermit(..., uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s) public {
 *     try token.permit(msg.sender, address(this), value, deadline, v, r, s) {} catch {}
 *     doThing(..., value);
 * }
 *
 * function doThing(..., uint256 value) public {
 *     token.safeTransferFrom(msg.sender, address(this), value);
 *     ...
 * }
 * ```
 *
 * Observe that: 1) `msg.sender` is used as the owner, leaving no ambiguity as to the signer intent, and 2) the use of
 * `try/catch` allows the permit to fail and makes the code tolerant to frontrunning. (See also
 * {SafeERC20-safeTransferFrom}).
 *
 * Additionally, note that smart contract wallets (such as Argent or Safe) are not able to produce permit signatures, so
 * contracts should have entry points that don't rely on permit.
 */
interface IERC20Permit {
    /**
     * @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,
     * given ``owner``'s signed approval.
     *
     * IMPORTANT: The same issues {IERC20-approve} has related to transaction
     * ordering also apply here.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `deadline` must be a timestamp in the future.
     * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
     * over the EIP712-formatted function arguments.
     * - the signature must use ``owner``'s current nonce (see {nonces}).
     *
     * For more information on the signature format, see the
     * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
     * section].
     *
     * CAUTION: See Security Considerations above.
     */
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external;

    /**
     * @dev Returns the current nonce for `owner`. This value must be
     * included whenever a signature is generated for {permit}.
     *
     * Every successful call to {permit} increases ``owner``'s nonce by one. This
     * prevents a signature from being used multiple times.
     */
    function nonces(address owner) external view returns (uint256);

    /**
     * @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.
     */
    // solhint-disable-next-line func-name-mixedcase
    function DOMAIN_SEPARATOR() external view returns (bytes32);
}

// File: lib/openzeppelin-contracts/contracts/utils/Address.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (utils/Address.sol)

pragma solidity ^0.8.20;

/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev The ETH balance of the account is not enough to perform the operation.
     */
    error AddressInsufficientBalance(address account);

    /**
     * @dev There's no code at `target` (it is not a contract).
     */
    error AddressEmptyCode(address target);

    /**
     * @dev A call to an address target failed. The target may have reverted.
     */
    error FailedInnerCall();

    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://consensys.net/diligence/blog/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.8.20/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        if (address(this).balance < amount) {
            revert AddressInsufficientBalance(address(this));
        }

        (bool success, ) = recipient.call{value: amount}("");
        if (!success) {
            revert FailedInnerCall();
        }
    }

    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain `call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason or custom error, it is bubbled
     * up by this function (like regular Solidity function calls). However, if
     * the call reverted with no returned reason, this function reverts with a
     * {FailedInnerCall} error.
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
        if (address(this).balance < value) {
            revert AddressInsufficientBalance(address(this));
        }
        (bool success, bytes memory returndata) = target.call{value: value}(data);
        return verifyCallResultFromTarget(target, success, returndata);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        (bool success, bytes memory returndata) = target.staticcall(data);
        return verifyCallResultFromTarget(target, success, returndata);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return verifyCallResultFromTarget(target, success, returndata);
    }

    /**
     * @dev Tool to verify that a low level call to smart-contract was successful, and reverts if the target
     * was not a contract or bubbling up the revert reason (falling back to {FailedInnerCall}) in case of an
     * unsuccessful call.
     */
    function verifyCallResultFromTarget(
        address target,
        bool success,
        bytes memory returndata
    ) internal view returns (bytes memory) {
        if (!success) {
            _revert(returndata);
        } else {
            // only check if target is a contract if the call was successful and the return data is empty
            // otherwise we already know that it was a contract
            if (returndata.length == 0 && target.code.length == 0) {
                revert AddressEmptyCode(target);
            }
            return returndata;
        }
    }

    /**
     * @dev Tool to verify that a low level call was successful, and reverts if it wasn't, either by bubbling the
     * revert reason or with a default {FailedInnerCall} error.
     */
    function verifyCallResult(bool success, bytes memory returndata) internal pure returns (bytes memory) {
        if (!success) {
            _revert(returndata);
        } else {
            return returndata;
        }
    }

    /**
     * @dev Reverts with returndata if present. Otherwise reverts with {FailedInnerCall}.
     */
    function _revert(bytes memory returndata) private pure {
        // 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
            /// @solidity memory-safe-assembly
            assembly {
                let returndata_size := mload(returndata)
                revert(add(32, returndata), returndata_size)
            }
        } else {
            revert FailedInnerCall();
        }
    }
}

// File: lib/openzeppelin-contracts/contracts/utils/Context.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (utils/Context.sol)

pragma solidity ^0.8.20;

/**
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}

// File: src/DividendToken.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "openzeppelin-contracts/contracts/token/ERC20/ERC20.sol";
import "openzeppelin-contracts/contracts/access/Ownable.sol";
import "./libraries/SafeMathUint.sol";
import "./libraries/SafeMathInt.sol";
import "./interfaces/IDividendPayingToken.sol";
import "./interfaces/IDividendPayingTokenOptional.sol";

/// @title Dividend-Paying Token
/// @author Roger Wu (https://github.com/roger-wu)
/// @dev A mintable ERC20 token that allows anyone to pay and distribute ether
///  to token holders as dividends and allows token holders to withdraw their dividends.
///  Reference: the source code of PoWH3D: https://etherscan.io/address/0xB3775fB83F7D12A36E0475aBdD1FCA35c091efBe#code
abstract contract DividendToken is ERC20, IDividendPayingToken, IDividendPayingTokenOptional, Ownable {
    using SafeMathUint for uint256;
    using SafeMathInt for int256;

    // With `magnitude`, we can properly distribute dividends even if the amount of received ether is small.
    // For more discussion about choosing the value of `magnitude`,
    //  see https://github.com/ethereum/EIPs/issues/1726#issuecomment-472352728
    uint256 internal constant magnitude = 10 ** 38;
    uint256 internal magnifiedDividendPerShare;
    uint256 internal lastAmount;
    uint256 public totalDividendsDistributed;
    uint256 public totalDividendsShares;
    // About dividendCorrection:
    // If the token balance of a `_user` is never changed, the dividend of `_user` can be computed with:
    //   `dividendOf(_user) = dividendPerShare * balanceOf(_user)`.
    // When `balanceOf(_user)` is changed (via minting/burning/transferring tokens),
    //   `dividendOf(_user)` should not be changed,
    //   but the computed value of `dividendPerShare * balanceOf(_user)` is changed.
    // To keep the `dividendOf(_user)` unchanged, we add a correction term:
    //   `dividendOf(_user) = dividendPerShare * balanceOf(_user) + dividendCorrectionOf(_user)`,
    //   where `dividendCorrectionOf(_user)` is updated whenever `balanceOf(_user)` is changed:
    //   `dividendCorrectionOf(_user) = dividendPerShare * (old balanceOf(_user)) - (new balanceOf(_user))`.
    // So now `dividendOf(_user)` returns the same value before and after `balanceOf(_user)` is changed.
    mapping(address => int256) internal magnifiedDividendCorrections;
    mapping(address => uint256) internal withdrawnDividends;

    constructor(string memory _name, string memory _symbol) ERC20(_name, _symbol) {}

    // public functions

    /// @notice Distributes ether to token holders as dividends.
    /// @dev It reverts if the total supply of tokens is 0.
    /// It emits the `DividendsDistributed` event if the amount of received ether is greater than 0.
    /// About undistributed ether:
    ///   In each distribution, there is a small amount of ether not distributed,
    ///     the magnified amount of which is
    ///     `(msg.value * magnitude) % totalSupply()`.
    ///   With a well-chosen `magnitude`, the amount of undistributed ether
    ///     (de-magnified) in a distribution can be less than 1 wei.
    ///   We can actually keep track of the undistributed ether in a distribution
    ///     and try to distribute it in the next distribution,
    ///     but keeping track of such data on-chain costs much more than
    ///     the saved ether, so we don't do that.
    function distributeDividends() public payable override {
        _distributeDividends(msg.value);
    }

    /// @notice View the amount of dividend in wei that an address can withdraw.
    /// @param _owner The address of a token holder.
    /// @return The amount of dividend in wei that `_owner` can withdraw.
    function dividendOf(address _owner) public view override returns (uint256) {
        uint256 _dividend = withdrawableDividendOf(_owner);
        return _dividend;
    }

    /// @notice View the amount of dividend in wei that an address can withdraw.
    /// @param _owner The address of a token holder.
    /// @return The amount of dividend in wei that `_owner` can withdraw.
    function withdrawableDividendOf(address _owner) public view override returns (uint256) {
        uint256 _withdrawable = accumulativeDividendOf(_owner) - (withdrawnDividends[_owner]);
        return _withdrawable;
    }

    /// @notice View the amount of dividend in wei that an address has withdrawn.
    /// @param _owner The address of a token holder.
    /// @return The amount of dividend in wei that `_owner` has withdrawn.
    function withdrawnDividendOf(address _owner) public view override returns (uint256) {
        uint256 _withdrawn = withdrawnDividends[_owner];
        return _withdrawn;
    }

    /// @notice View the amount of dividend in wei that an address has earned in total.
    /// @dev accumulativeDividendOf(_owner) = withdrawableDividendOf(_owner) + withdrawnDividendOf(_owner)
    /// = (magnifiedDividendPerShare * balanceOf(_owner) + magnifiedDividendCorrections[_owner]) / magnitude
    /// @param _owner The address of a token holder.
    /// @return The amount of dividend in wei that `_owner` has earned in total.
    function accumulativeDividendOf(address _owner) public view override returns (uint256) {
        uint256 _accumulative = (
            (magnifiedDividendPerShare * _dividendShare(_owner)).toInt256Safe() + magnifiedDividendCorrections[_owner]
        ).toUint256Safe() / magnitude;
        return _accumulative;
    }

    // internal functions

    /// @notice Withdraws the ether distributed to the sender.
    /// @dev It emits a `DividendWithdrawn` event if the amount of withdrawn ether is greater than 0.
    function _withdrawDividendOfUser(address payable user) internal returns (uint256) {
        uint256 _withdrawableDividend = withdrawableDividendOf(user);
        if (_withdrawableDividend > 0) {
            withdrawnDividends[user] = withdrawnDividends[user] + _withdrawableDividend;
            (bool success,) = user.call{value: _withdrawableDividend, gas: 3000}("");
            if (!success) {
                return 0;
            }
            return _withdrawableDividend;
        }
        return 0;
    }

    function _dividendShare(address _account) internal view virtual returns (uint256 _share);

    function _distributeDividends(uint256 amount) internal {
        require(totalDividendsShares > 0, "0 dividend totalsupply");
        if (amount > 0) {
            magnifiedDividendPerShare = magnifiedDividendPerShare + (amount * magnitude / totalDividendsShares);
            emit DividendsDistributed(msg.sender, amount);
            totalDividendsDistributed = totalDividendsDistributed + amount;
        }
    }

    /// @dev Internal function that mints tokens to an account.
    /// Update magnifiedDividendCorrections to keep dividends unchanged.
    /// @param account The account that will receive the created tokens.
    /// @param value The amount that will be created.
    function _processMint(address account, uint256 value) internal {
        int256 _correction =
            magnifiedDividendCorrections[account] - ((magnifiedDividendPerShare * value).toInt256Safe());
        magnifiedDividendCorrections[account] = _correction;
    }

    /// @dev Internal function that burns an amount of the token of a given account.
    /// Update magnifiedDividendCorrections to keep dividends unchanged.
    /// @param account The account whose tokens will be burnt.
    /// @param value The amount that will be burnt.
    function _processBurn(address account, uint256 value) internal {
        int256 _correction =
            magnifiedDividendCorrections[account] + ((magnifiedDividendPerShare * value).toInt256Safe());
        magnifiedDividendCorrections[account] = _correction;
    }

    /// @dev Internal function that adjusts an address dividends shares according to the new token balance.
    /// @param account The account whose tokens will be proccessed .
    /// @param newBalance The new address balance.
    function _setBalance(address account, uint256 newBalance) internal {
        uint256 currentBalance = _dividendShare(account);
        if (newBalance > currentBalance) {
            uint256 mintAmount = newBalance - currentBalance;
            totalDividendsShares += mintAmount;
            _processMint(account, mintAmount);
        } else if (newBalance < currentBalance) {
            uint256 burnAmount = currentBalance - newBalance;
            totalDividendsShares -= burnAmount;
            _processBurn(account, burnAmount);
        }
    }
}

// File: lib/openzeppelin-contracts/contracts/token/ERC20/ERC20.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/ERC20.sol)

pragma solidity ^0.8.20;

import {IERC20} from "./IERC20.sol";
import {IERC20Metadata} from "./extensions/IERC20Metadata.sol";
import {Context} from "../../utils/Context.sol";
import {IERC20Errors} from "../../interfaces/draft-IERC6093.sol";

/**
 * @dev Implementation of the {IERC20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.openzeppelin.com/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * The default value of {decimals} is 18. To change this, you should override
 * this function so it returns a different value.
 *
 * We have followed general OpenZeppelin Contracts guidelines: functions revert
 * instead returning `false` on failure. This behavior is nonetheless
 * conventional and does not conflict with the expectations of ERC20
 * applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 */
abstract contract ERC20 is Context, IERC20, IERC20Metadata, IERC20Errors {
    mapping(address account => uint256) private _balances;

    mapping(address account => mapping(address spender => uint256)) private _allowances;

    uint256 private _totalSupply;

    string private _name;
    string private _symbol;

    /**
     * @dev Sets the values for {name} and {symbol}.
     *
     * All two of these values are immutable: they can only be set once during
     * construction.
     */
    constructor(string memory name_, string memory symbol_) {
        _name = name_;
        _symbol = symbol_;
    }

    /**
     * @dev Returns the name of the token.
     */
    function name() public view virtual returns (string memory) {
        return _name;
    }

    /**
     * @dev Returns the symbol of the token, usually a shorter version of the
     * name.
     */
    function symbol() public view virtual returns (string memory) {
        return _symbol;
    }

    /**
     * @dev Returns the number of decimals used to get its user representation.
     * For example, if `decimals` equals `2`, a balance of `505` tokens should
     * be displayed to a user as `5.05` (`505 / 10 ** 2`).
     *
     * Tokens usually opt for a value of 18, imitating the relationship between
     * Ether and Wei. This is the default value returned by this function, unless
     * it's overridden.
     *
     * NOTE: This information is only used for _display_ purposes: it in
     * no way affects any of the arithmetic of the contract, including
     * {IERC20-balanceOf} and {IERC20-transfer}.
     */
    function decimals() public view virtual returns (uint8) {
        return 18;
    }

    /**
     * @dev See {IERC20-totalSupply}.
     */
    function totalSupply() public view virtual returns (uint256) {
        return _totalSupply;
    }

    /**
     * @dev See {IERC20-balanceOf}.
     */
    function balanceOf(address account) public view virtual returns (uint256) {
        return _balances[account];
    }

    /**
     * @dev See {IERC20-transfer}.
     *
     * Requirements:
     *
     * - `to` cannot be the zero address.
     * - the caller must have a balance of at least `value`.
     */
    function transfer(address to, uint256 value) public virtual returns (bool) {
        address owner = _msgSender();
        _transfer(owner, to, value);
        return true;
    }

    /**
     * @dev See {IERC20-allowance}.
     */
    function allowance(address owner, address spender) public view virtual returns (uint256) {
        return _allowances[owner][spender];
    }

    /**
     * @dev See {IERC20-approve}.
     *
     * NOTE: If `value` is the maximum `uint256`, the allowance is not updated on
     * `transferFrom`. This is semantically equivalent to an infinite approval.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function approve(address spender, uint256 value) public virtual returns (bool) {
        address owner = _msgSender();
        _approve(owner, spender, value);
        return true;
    }

    /**
     * @dev See {IERC20-transferFrom}.
     *
     * Emits an {Approval} event indicating the updated allowance. This is not
     * required by the EIP. See the note at the beginning of {ERC20}.
     *
     * NOTE: Does not update the allowance if the current allowance
     * is the maximum `uint256`.
     *
     * Requirements:
     *
     * - `from` and `to` cannot be the zero address.
     * - `from` must have a balance of at least `value`.
     * - the caller must have allowance for ``from``'s tokens of at least
     * `value`.
     */
    function transferFrom(address from, address to, uint256 value) public virtual returns (bool) {
        address spender = _msgSender();
        _spendAllowance(from, spender, value);
        _transfer(from, to, value);
        return true;
    }

    /**
     * @dev Moves a `value` amount of tokens from `from` to `to`.
     *
     * This internal function is equivalent to {transfer}, and can be used to
     * e.g. implement automatic token fees, slashing mechanisms, etc.
     *
     * Emits a {Transfer} event.
     *
     * NOTE: This function is not virtual, {_update} should be overridden instead.
     */
    function _transfer(address from, address to, uint256 value) internal {
        if (from == address(0)) {
            revert ERC20InvalidSender(address(0));
        }
        if (to == address(0)) {
            revert ERC20InvalidReceiver(address(0));
        }
        _update(from, to, value);
    }

    /**
     * @dev Transfers a `value` amount of tokens from `from` to `to`, or alternatively mints (or burns) if `from`
     * (or `to`) is the zero address. All customizations to transfers, mints, and burns should be done by overriding
     * this function.
     *
     * Emits a {Transfer} event.
     */
    function _update(address from, address to, uint256 value) internal virtual {
        if (from == address(0)) {
            // Overflow check required: The rest of the code assumes that totalSupply never overflows
            _totalSupply += value;
        } else {
            uint256 fromBalance = _balances[from];
            if (fromBalance < value) {
                revert ERC20InsufficientBalance(from, fromBalance, value);
            }
            unchecked {
                // Overflow not possible: value <= fromBalance <= totalSupply.
                _balances[from] = fromBalance - value;
            }
        }

        if (to == address(0)) {
            unchecked {
                // Overflow not possible: value <= totalSupply or value <= fromBalance <= totalSupply.
                _totalSupply -= value;
            }
        } else {
            unchecked {
                // Overflow not possible: balance + value is at most totalSupply, which we know fits into a uint256.
                _balances[to] += value;
            }
        }

        emit Transfer(from, to, value);
    }

    /**
     * @dev Creates a `value` amount of tokens and assigns them to `account`, by transferring it from address(0).
     * Relies on the `_update` mechanism
     *
     * Emits a {Transfer} event with `from` set to the zero address.
     *
     * NOTE: This function is not virtual, {_update} should be overridden instead.
     */
    function _mint(address account, uint256 value) internal {
        if (account == address(0)) {
            revert ERC20InvalidReceiver(address(0));
        }
        _update(address(0), account, value);
    }

    /**
     * @dev Destroys a `value` amount of tokens from `account`, lowering the total supply.
     * Relies on the `_update` mechanism.
     *
     * Emits a {Transfer} event with `to` set to the zero address.
     *
     * NOTE: This function is not virtual, {_update} should be overridden instead
     */
    function _burn(address account, uint256 value) internal {
        if (account == address(0)) {
            revert ERC20InvalidSender(address(0));
        }
        _update(account, address(0), value);
    }

    /**
     * @dev Sets `value` as the allowance of `spender` over the `owner` s tokens.
     *
     * This internal function is equivalent to `approve`, and can be used to
     * e.g. set automatic allowances for certain subsystems, etc.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `owner` cannot be the zero address.
     * - `spender` cannot be the zero address.
     *
     * Overrides to this logic should be done to the variant with an additional `bool emitEvent` argument.
     */
    function _approve(address owner, address spender, uint256 value) internal {
        _approve(owner, spender, value, true);
    }

    /**
     * @dev Variant of {_approve} with an optional flag to enable or disable the {Approval} event.
     *
     * By default (when calling {_approve}) the flag is set to true. On the other hand, approval changes made by
     * `_spendAllowance` during the `transferFrom` operation set the flag to false. This saves gas by not emitting any
     * `Approval` event during `transferFrom` operations.
     *
     * Anyone who wishes to continue emitting `Approval` events on the`transferFrom` operation can force the flag to
     * true using the following override:
     * ```
     * function _approve(address owner, address spender, uint256 value, bool) internal virtual override {
     *     super._approve(owner, spender, value, true);
     * }
     * ```
     *
     * Requirements are the same as {_approve}.
     */
    function _approve(address owner, address spender, uint256 value, bool emitEvent) internal virtual {
        if (owner == address(0)) {
            revert ERC20InvalidApprover(address(0));
        }
        if (spender == address(0)) {
            revert ERC20InvalidSpender(address(0));
        }
        _allowances[owner][spender] = value;
        if (emitEvent) {
            emit Approval(owner, spender, value);
        }
    }

    /**
     * @dev Updates `owner` s allowance for `spender` based on spent `value`.
     *
     * Does not update the allowance value in case of infinite allowance.
     * Revert if not enough allowance is available.
     *
     * Does not emit an {Approval} event.
     */
    function _spendAllowance(address owner, address spender, uint256 value) internal virtual {
        uint256 currentAllowance = allowance(owner, spender);
        if (currentAllowance != type(uint256).max) {
            if (currentAllowance < value) {
                revert ERC20InsufficientAllowance(spender, currentAllowance, value);
            }
            unchecked {
                _approve(owner, spender, currentAllowance - value, false);
            }
        }
    }
}

// File: src/libraries/SafeMathUint.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @title SafeMathUint
 * @dev Math operations with safety checks that revert on error
 */
library SafeMathUint {
  function toInt256Safe(uint256 a) internal pure returns (int256) {
    int256 b = int256(a);
    require(b >= 0,"Negative number is not allowed");
    return b;
  }
}
// File: src/libraries/SafeMathInt.sol



// SPDX-License-Identifier: MIT

/*
MIT License

Copyright (c) 2018 requestnetwork
Copyright (c) 2018 Fragments, Inc.

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
*/

pragma solidity ^0.8.0;

/**
 * @title SafeMathInt
 * @dev Math operations for int256 with overflow safety checks.
 */
library SafeMathInt {
    int256 private constant MIN_INT256 = int256(1) << 255;
    int256 private constant MAX_INT256 = ~(int256(1) << 255);

    /**
     * @dev Multiplies two int256 variables and fails on overflow.
     */
    function mul(int256 a, int256 b) internal pure returns (int256) {
        int256 c = a * b;

        // Detect overflow when multiplying MIN_INT256 with -1
        require(c != MIN_INT256 || (a & MIN_INT256) != (b & MIN_INT256),"multplitiy error");
        require((b == 0) || (c / b == a),"multiplity error mul");
        return c;
    }

    /**
     * @dev Division of two int256 variables and fails on overflow.
     */
    function div(int256 a, int256 b) internal pure returns (int256) {
        // Prevent overflow when dividing MIN_INT256 by -1
        require(b != -1 || a != MIN_INT256,"SafeMath error div");

        // Solidity already throws when dividing by 0.
        return a / b;
    }

    /**
     * @dev Subtracts two int256 variables and fails on overflow.
     */
    function sub(int256 a, int256 b) internal pure returns (int256) {
        int256 c = a - b;
        require((b >= 0 && c <= a) || (b < 0 && c > a),"SafeMath error sub");
        return c;
    }

    /**
     * @dev Adds two int256 variables and fails on overflow.
     */
    function add(int256 a, int256 b) internal pure returns (int256) {
        int256 c = a + b;
        require((b >= 0 && c >= a) || (b < 0 && c < a),"SafeMath error add");
        return c;
    }

    /**
     * @dev Converts to absolute value, and fails on overflow.
     */
    function abs(int256 a) internal pure returns (int256) {
        require(a != MIN_INT256,"SafeMath error abs");
        return a < 0 ? -a : a;
    }


    function toUint256Safe(int256 a) internal pure returns (uint256) {
        require(a >= 0,"SafeMath toUint error");
        return uint256(a);
    }
}
// File: src/interfaces/IDividendPayingToken.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;


/// @title Dividend-Paying Token Interface
/// @author Roger Wu (https://github.com/roger-wu)
/// @dev An interface for a dividend-paying token contract.
interface IDividendPayingToken {
  /// @notice View the amount of dividend in wei that an address can withdraw.
  /// @param _owner The address of a token holder.
  /// @return The amount of dividend in wei that `_owner` can withdraw.
  function dividendOf(address _owner) external view returns(uint256);

  /// @notice Distributes ether to token holders as dividends.
  /// @dev SHOULD distribute the paid ether to token holders as dividends.
  ///  SHOULD NOT directly transfer ether to token holders in this function.
  ///  MUST emit a `DividendsDistributed` event when the amount of distributed ether is greater than 0.
  function distributeDividends() external payable;

  /// @dev This event MUST emit when ether is distributed to token holders.
  /// @param from The address which sends ether to this contract.
  /// @param weiAmount The amount of distributed ether in wei.
  event DividendsDistributed(
    address indexed from,
    uint256 weiAmount
  );

  /// @dev This event MUST emit when an address withdraws their dividend.
  /// @param to The address which withdraws ether from this contract.
  /// @param weiAmount The amount of withdrawn ether in wei.
  event DividendWithdrawn(
    address indexed to,
    uint256 weiAmount
  );
}
// File: src/interfaces/IDividendPayingTokenOptional.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;


/// @title Dividend-Paying Token Optional Interface
/// @author Roger Wu (https://github.com/roger-wu)
/// @dev OPTIONAL functions for a dividend-paying token contract.
interface IDividendPayingTokenOptional {
  /// @notice View the amount of dividend in wei that an address can withdraw.
  /// @param _owner The address of a token holder.
  /// @return The amount of dividend in wei that `_owner` can withdraw.
  function withdrawableDividendOf(address _owner) external view returns(uint256);

  /// @notice View the amount of dividend in wei that an address has withdrawn.
  /// @param _owner The address of a token holder.
  /// @return The amount of dividend in wei that `_owner` has withdrawn.
  function withdrawnDividendOf(address _owner) external view returns(uint256);

  /// @notice View the amount of dividend in wei that an address has earned in total.
  /// @dev accumulativeDividendOf(_owner) = withdrawableDividendOf(_owner) + withdrawnDividendOf(_owner)
  /// @param _owner The address of a token holder.
  /// @return The amount of dividend in wei that `_owner` has earned in total.
  function accumulativeDividendOf(address _owner) external view returns(uint256);
}
// File: lib/openzeppelin-contracts/contracts/token/ERC20/extensions/IERC20Metadata.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/extensions/IERC20Metadata.sol)

pragma solidity ^0.8.20;

import {IERC20} from "../IERC20.sol";

/**
 * @dev Interface for the optional metadata functions from the ERC20 standard.
 */
interface IERC20Metadata is IERC20 {
    /**
     * @dev Returns the name of the token.
     */
    function name() external view returns (string memory);

    /**
     * @dev Returns the symbol of the token.
     */
    function symbol() external view returns (string memory);

    /**
     * @dev Returns the decimals places of the token.
     */
    function decimals() external view returns (uint8);
}

// File: lib/openzeppelin-contracts/contracts/interfaces/draft-IERC6093.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (interfaces/draft-IERC6093.sol)
pragma solidity ^0.8.20;

/**
 * @dev Standard ERC20 Errors
 * Interface of the https://eips.ethereum.org/EIPS/eip-6093[ERC-6093] custom errors for ERC20 tokens.
 */
interface IERC20Errors {
    /**
     * @dev Indicates an error related to the current `balance` of a `sender`. Used in transfers.
     * @param sender Address whose tokens are being transferred.
     * @param balance Current balance for the interacting account.
     * @param needed Minimum amount required to perform a transfer.
     */
    error ERC20InsufficientBalance(address sender, uint256 balance, uint256 needed);

    /**
     * @dev Indicates a failure with the token `sender`. Used in transfers.
     * @param sender Address whose tokens are being transferred.
     */
    error ERC20InvalidSender(address sender);

    /**
     * @dev Indicates a failure with the token `receiver`. Used in transfers.
     * @param receiver Address to which tokens are being transferred.
     */
    error ERC20InvalidReceiver(address receiver);

    /**
     * @dev Indicates a failure with the `spender`’s `allowance`. Used in transfers.
     * @param spender Address that may be allowed to operate on tokens without being their owner.
     * @param allowance Amount of tokens a `spender` is allowed to operate with.
     * @param needed Minimum amount required to perform a transfer.
     */
    error ERC20InsufficientAllowance(address spender, uint256 allowance, uint256 needed);

    /**
     * @dev Indicates a failure with the `approver` of a token to be approved. Used in approvals.
     * @param approver Address initiating an approval operation.
     */
    error ERC20InvalidApprover(address approver);

    /**
     * @dev Indicates a failure with the `spender` to be approved. Used in approvals.
     * @param spender Address that may be allowed to operate on tokens without being their owner.
     */
    error ERC20InvalidSpender(address spender);
}

/**
 * @dev Standard ERC721 Errors
 * Interface of the https://eips.ethereum.org/EIPS/eip-6093[ERC-6093] custom errors for ERC721 tokens.
 */
interface IERC721Errors {
    /**
     * @dev Indicates that an address can't be an owner. For example, `address(0)` is a forbidden owner in EIP-20.
     * Used in balance queries.
     * @param owner Address of the current owner of a token.
     */
    error ERC721InvalidOwner(address owner);

    /**
     * @dev Indicates a `tokenId` whose `owner` is the zero address.
     * @param tokenId Identifier number of a token.
     */
    error ERC721NonexistentToken(uint256 tokenId);

    /**
     * @dev Indicates an error related to the ownership over a particular token. Used in transfers.
     * @param sender Address whose tokens are being transferred.
     * @param tokenId Identifier number of a token.
     * @param owner Address of the current owner of a token.
     */
    error ERC721IncorrectOwner(address sender, uint256 tokenId, address owner);

    /**
     * @dev Indicates a failure with the token `sender`. Used in transfers.
     * @param sender Address whose tokens are being transferred.
     */
    error ERC721InvalidSender(address sender);

    /**
     * @dev Indicates a failure with the token `receiver`. Used in transfers.
     * @param receiver Address to which tokens are being transferred.
     */
    error ERC721InvalidReceiver(address receiver);

    /**
     * @dev Indicates a failure with the `operator`’s approval. Used in transfers.
     * @param operator Address that may be allowed to operate on tokens without being their owner.
     * @param tokenId Identifier number of a token.
     */
    error ERC721InsufficientApproval(address operator, uint256 tokenId);

    /**
     * @dev Indicates a failure with the `approver` of a token to be approved. Used in approvals.
     * @param approver Address initiating an approval operation.
     */
    error ERC721InvalidApprover(address approver);

    /**
     * @dev Indicates a failure with the `operator` to be approved. Used in approvals.
     * @param operator Address that may be allowed to operate on tokens without being their owner.
     */
    error ERC721InvalidOperator(address operator);
}

/**
 * @dev Standard ERC1155 Errors
 * Interface of the https://eips.ethereum.org/EIPS/eip-6093[ERC-6093] custom errors for ERC1155 tokens.
 */
interface IERC1155Errors {
    /**
     * @dev Indicates an error related to the current `balance` of a `sender`. Used in transfers.
     * @param sender Address whose tokens are being transferred.
     * @param balance Current balance for the interacting account.
     * @param needed Minimum amount required to perform a transfer.
     * @param tokenId Identifier number of a token.
     */
    error ERC1155InsufficientBalance(address sender, uint256 balance, uint256 needed, uint256 tokenId);

    /**
     * @dev Indicates a failure with the token `sender`. Used in transfers.
     * @param sender Address whose tokens are being transferred.
     */
    error ERC1155InvalidSender(address sender);

    /**
     * @dev Indicates a failure with the token `receiver`. Used in transfers.
     * @param receiver Address to which tokens are being transferred.
     */
    error ERC1155InvalidReceiver(address receiver);

    /**
     * @dev Indicates a failure with the `operator`’s approval. Used in transfers.
     * @param operator Address that may be allowed to operate on tokens without being their owner.
     * @param owner Address of the current owner of a token.
     */
    error ERC1155MissingApprovalForAll(address operator, address owner);

    /**
     * @dev Indicates a failure with the `approver` of a token to be approved. Used in approvals.
     * @param approver Address initiating an approval operation.
     */
    error ERC1155InvalidApprover(address approver);

    /**
     * @dev Indicates a failure with the `operator` to be approved. Used in approvals.
     * @param operator Address that may be allowed to operate on tokens without being their owner.
     */
    error ERC1155InvalidOperator(address operator);

    /**
     * @dev Indicates an array length mismatch between ids and values in a safeBatchTransferFrom operation.
     * Used in batch transfers.
     * @param idsLength Length of the array of token identifiers
     * @param valuesLength Length of the array of token amounts
     */
    error ERC1155InvalidArrayLength(uint256 idsLength, uint256 valuesLength);
}