// File: @openzeppelin/contracts/access/Ownable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)

pragma solidity ^0.8.0;

import "../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.
 *
 * By default, the owner account will be the one that deploys the contract. 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;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor() {
        _transferOwnership(_msgSender());
    }

    /**
     * @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 {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        _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 {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        _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: @openzeppelin/contracts/utils/Address.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (utils/Address.sol)

pragma solidity ^0.8.1;

/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     *
     * [IMPORTANT]
     * ====
     * You shouldn't rely on `isContract` to protect against flash loan attacks!
     *
     * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
     * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
     * constructor.
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize/address.code.length, which returns 0
        // for contracts in construction, since the code is only stored at the end
        // of the constructor execution.

        return account.code.length > 0;
    }

    /**
     * @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://diligence.consensys.net/posts/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/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");

        (bool success, ) = recipient.call{value: amount}("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }

    /**
     * @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, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * 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.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionCall(target, data, "Address: low-level call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }

    /**
     * @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`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }

    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        require(isContract(target), "Address: call to non-contract");

        (bool success, bytes memory returndata) = target.call{value: value}(data);
        return verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        require(isContract(target), "Address: static call to non-contract");

        (bool success, bytes memory returndata) = target.staticcall(data);
        return verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(isContract(target), "Address: delegate call to non-contract");

        (bool success, bytes memory returndata) = target.delegatecall(data);
        return verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
     * revert reason using the provided one.
     *
     * _Available since v4.3._
     */
    function verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly
                /// @solidity memory-safe-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

// File: @openzeppelin/contracts/utils/Context.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)

pragma solidity ^0.8.0;

/**
 * @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: contracts/ABC.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.8.9;

import "./ERC20.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/utils/Address.sol";

contract ABC is ERC20, Ownable {
    uint256 private constant MAX_BPS = 100_00;

    uint256 public immutable start;
    uint256 public immutable end;
    uint256 public immutable initialPenalty;

    uint96 public fee;
    address public pair;
    bool private active;

    mapping(address => bool) public whitelisted;

    constructor() ERC20("ABC Token", "ABC", 18) {
        start = block.timestamp;
        initialPenalty = 7_00; // 7%
        end = block.timestamp + 30 days;
        fee = 3_33; // 3.33%
        active = false;

        require(initialPenalty <= MAX_BPS, "max penalty is 100%");
        require(fee <= MAX_BPS, "max fee is 100%");
        require(start <= end, "start must be <= end");

        whitelisted[msg.sender] = true;

        _mint(msg.sender, 250_000_000e18);
    }

    function currentPenalty() public view returns (uint256 _penalty) {
        if (block.timestamp < end) {
            unchecked {
                uint256 _remaining = end - block.timestamp;
                _penalty = (initialPenalty * _remaining) / (end - start);
            }
        }
    }

    function _transfer(address sender_, address recipient_, uint256 amount_) internal override {
        if (!whitelisted[sender_]) {
            require(active, "!active");

            uint256 _feeAmount = (amount_ * fee) / MAX_BPS;

            // Burn penalty
            if (sender_ != pair && block.timestamp < end) {
                uint256 _burnt = (amount_ * currentPenalty()) / MAX_BPS;

                if (_burnt > 0) {
                    super._transfer(sender_, address(0), _burnt);

                    // `_burnt` is always <= `amount_`
                    unchecked {
                        amount_ -= _burnt;
                    }
                }
            }

            // Collect fee
            if (_feeAmount > 0) {
                super._transfer(sender_, owner(), _feeAmount);
                // `_feeAmount` is always <= `amount_`
                unchecked {
                    amount_ -= _feeAmount;
                }
            }
        }

        super._transfer(sender_, recipient_, amount_);
    }

    function updatePair(address pair_) external onlyOwner {
        pair = pair_;
        active = true;
    }

    function updateFee(uint96 fee_) external onlyOwner {
        require(fee_ <= MAX_BPS, "max fee is 100%");
        fee = fee_;
    }

    function toggleWhitelist(address address_) external onlyOwner {
        whitelisted[address_] = !whitelisted[address_];
    }

    function sweep(IERC20 token_) external onlyOwner {
        if (address(token_) == address(0)) {
            Address.sendValue(payable(owner()), address(this).balance);
        } else {
            token_.transfer(owner(), token_.balanceOf(address(this)));
        }
    }
}

// File: contracts/ERC20.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.7;

import {IERC20} from "./interfaces/IERC20.sol";

/*
    ███████╗██████╗  ██████╗    ██████╗  ██████╗
    ██╔════╝██╔══██╗██╔════╝    ╚════██╗██╔═████╗
    █████╗  ██████╔╝██║          █████╔╝██║██╔██║
    ██╔══╝  ██╔══██╗██║         ██╔═══╝ ████╔╝██║
    ███████╗██║  ██║╚██████╗    ███████╗╚██████╔╝
    ╚══════╝╚═╝  ╚═╝ ╚═════╝    ╚══════╝ ╚═════╝
*/

/**
 *  @title Modern ERC-20 implementation.
 *  @dev   Acknowledgements to Solmate, OpenZeppelin, and DSS for inspiring this code.
 */
contract ERC20 is IERC20 {
    /**************/
    /*** ERC-20 ***/
    /**************/

    string public override name;
    string public override symbol;

    uint8 public immutable override decimals;

    uint256 public override totalSupply;

    mapping(address => uint256) public override balanceOf;

    mapping(address => mapping(address => uint256)) public override allowance;

    /**
     *  @param name_     The name of the token.
     *  @param symbol_   The symbol of the token.
     *  @param decimals_ The decimal precision used by the token.
     */
    constructor(
        string memory name_,
        string memory symbol_,
        uint8 decimals_
    ) {
        name = name_;
        symbol = symbol_;
        decimals = decimals_;
    }

    /**************************/
    /*** External Functions ***/
    /**************************/

    function approve(address spender_, uint256 amount_) public virtual override returns (bool success_) {
        _approve(msg.sender, spender_, amount_);
        return true;
    }

    function decreaseAllowance(address spender_, uint256 subtractedAmount_)
        public
        virtual
        override
        returns (bool success_)
    {
        _decreaseAllowance(msg.sender, spender_, subtractedAmount_);
        return true;
    }

    function increaseAllowance(address spender_, uint256 addedAmount_) public virtual override returns (bool success_) {
        _approve(msg.sender, spender_, allowance[msg.sender][spender_] + addedAmount_);
        return true;
    }

    function transfer(address recipient_, uint256 amount_) public virtual override returns (bool success_) {
        _transfer(msg.sender, recipient_, amount_);
        return true;
    }

    function transferFrom(
        address owner_,
        address recipient_,
        uint256 amount_
    ) public virtual override returns (bool success_) {
        _decreaseAllowance(owner_, msg.sender, amount_);
        _transfer(owner_, recipient_, amount_);
        return true;
    }

    /**************************/
    /*** Internal Functions ***/
    /**************************/

    function _approve(
        address owner_,
        address spender_,
        uint256 amount_
    ) internal {
        emit Approval(owner_, spender_, allowance[owner_][spender_] = amount_);
    }

    function _burn(address owner_, uint256 amount_) internal {
        balanceOf[owner_] -= amount_;

        // Cannot underflow because a user's balance will never be larger than the total supply.
        unchecked {
            totalSupply -= amount_;
        }

        emit Transfer(owner_, address(0), amount_);
    }

    function _decreaseAllowance(
        address owner_,
        address spender_,
        uint256 subtractedAmount_
    ) internal {
        uint256 spenderAllowance = allowance[owner_][spender_]; // Cache to memory.

        if (spenderAllowance != type(uint256).max) {
            _approve(owner_, spender_, spenderAllowance - subtractedAmount_);
        }
    }

    function _mint(address recipient_, uint256 amount_) internal {
        totalSupply += amount_;

        // Cannot overflow because totalSupply would first overflow in the statement above.
        unchecked {
            balanceOf[recipient_] += amount_;
        }

        emit Transfer(address(0), recipient_, amount_);
    }

    function _transfer(
        address owner_,
        address recipient_,
        uint256 amount_
    ) internal virtual {
        balanceOf[owner_] -= amount_;

        // Cannot overflow because minting prevents overflow of totalSupply, and sum of user balances == totalSupply.
        unchecked {
            balanceOf[recipient_] += amount_;
        }

        emit Transfer(owner_, recipient_, amount_);
    }
}

// File: contracts/interfaces/IERC20.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.7;

/// @title Interface of the ERC20 standard as defined in the EIP, including EIP-2612 permit functionality.
interface IERC20 {
    /**************/
    /*** Events ***/
    /**************/

    /**
     *  @dev   Emitted when one account has set the allowance of another account over their tokens.
     *  @param owner_   Account that tokens are approved from.
     *  @param spender_ Account that tokens are approved for.
     *  @param amount_  Amount of tokens that have been approved.
     */
    event Approval(address indexed owner_, address indexed spender_, uint256 amount_);

    /**
     *  @dev   Emitted when tokens have moved from one account to another.
     *  @param owner_     Account that tokens have moved from.
     *  @param recipient_ Account that tokens have moved to.
     *  @param amount_    Amount of tokens that have been transferred.
     */
    event Transfer(address indexed owner_, address indexed recipient_, uint256 amount_);

    /**************************/
    /*** External Functions ***/
    /**************************/

    /**
     *  @dev    Function that allows one account to set the allowance of another account over their tokens.
     *          Emits an {Approval} event.
     *  @param  spender_ Account that tokens are approved for.
     *  @param  amount_  Amount of tokens that have been approved.
     *  @return success_ Boolean indicating whether the operation succeeded.
     */
    function approve(address spender_, uint256 amount_) external returns (bool success_);

    /**
     *  @dev    Function that allows one account to decrease the allowance of another account over their tokens.
     *          Emits an {Approval} event.
     *  @param  spender_          Account that tokens are approved for.
     *  @param  subtractedAmount_ Amount to decrease approval by.
     *  @return success_          Boolean indicating whether the operation succeeded.
     */
    function decreaseAllowance(address spender_, uint256 subtractedAmount_) external returns (bool success_);

    /**
     *  @dev    Function that allows one account to increase the allowance of another account over their tokens.
     *          Emits an {Approval} event.
     *  @param  spender_     Account that tokens are approved for.
     *  @param  addedAmount_ Amount to increase approval by.
     *  @return success_     Boolean indicating whether the operation succeeded.
     */
    function increaseAllowance(address spender_, uint256 addedAmount_) external returns (bool success_);

    /**
     *  @dev    Moves an amount of tokens from `msg.sender` to a specified account.
     *          Emits a {Transfer} event.
     *  @param  recipient_ Account that receives tokens.
     *  @param  amount_    Amount of tokens that are transferred.
     *  @return success_   Boolean indicating whether the operation succeeded.
     */
    function transfer(address recipient_, uint256 amount_) external returns (bool success_);

    /**
     *  @dev    Moves a pre-approved amount of tokens from a sender to a specified account.
     *          Emits a {Transfer} event.
     *          Emits an {Approval} event.
     *  @param  owner_     Account that tokens are moving from.
     *  @param  recipient_ Account that receives tokens.
     *  @param  amount_    Amount of tokens that are transferred.
     *  @return success_   Boolean indicating whether the operation succeeded.
     */
    function transferFrom(
        address owner_,
        address recipient_,
        uint256 amount_
    ) external returns (bool success_);

    /**********************/
    /*** View Functions ***/
    /**********************/

    /**
     *  @dev    Returns the allowance that one account has given another over their tokens.
     *  @param  owner_     Account that tokens are approved from.
     *  @param  spender_   Account that tokens are approved for.
     *  @return allowance_ Allowance that one account has given another over their tokens.
     */
    function allowance(address owner_, address spender_) external view returns (uint256 allowance_);

    /**
     *  @dev    Returns the amount of tokens owned by a given account.
     *  @param  account_ Account that owns the tokens.
     *  @return balance_ Amount of tokens owned by a given account.
     */
    function balanceOf(address account_) external view returns (uint256 balance_);

    /**
     *  @dev    Returns the decimal precision used by the token.
     *  @return decimals_ The decimal precision used by the token.
     */
    function decimals() external view returns (uint8 decimals_);

    /**
     *  @dev    Returns the name of the token.
     *  @return name_ The name of the token.
     */
    function name() external view returns (string memory name_);

    /**
     *  @dev    Returns the symbol of the token.
     *  @return symbol_ The symbol of the token.
     */
    function symbol() external view returns (string memory symbol_);

    /**
     *  @dev    Returns the total amount of tokens in existence.
     *  @return totalSupply_ The total amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256 totalSupply_);
}