Contract Source Code:

// File contracts/libs/Context.sol

pragma solidity ^0.8.18;

/**
 * @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/libs/Ownable.sol

pragma solidity ^0.8.18;

/**
 * @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;

  mapping(address => bool) private _operators;

  /**
   * @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);
  event UpdateOperator(address indexed operator, bool authorized);

  /**
   * @dev Initializes the contract setting the deployer as the initial owner.
   */
  constructor(address initialOwner) {
    _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);
  }

  /**
   * @dev add / remove operators.
   * `operator`: operator address
   * `authorized`: authorized or not
   */
  function updateOperator(address operator, bool authorized) public onlyOwner {
    require(operator != address(0), "Ownable: operator is the zero address");
    emit UpdateOperator(operator, authorized);
    _operators[operator] = authorized;
  }

  /**
   * @dev Throws if called by any account other than the operators.
   */
  modifier onlyOperator() {
    require(_operators[_msgSender()], "Ownable: caller is not the operator");
    _;
  }
}


// File contracts/libs/Pausable.sol

pragma solidity ^0.8.18;

/**
 * @dev Contract module which allows children to implement an emergency stop
 * mechanism that can be triggered by an authorized account.
 *
 * This module is used through inheritance. It will make available the
 * modifiers `whenNotPaused` and `whenPaused`, which can be applied to
 * the functions of your contract. Note that they will not be pausable by
 * simply including this module, only once the modifiers are put in place.
 */
abstract contract Pausable is Context {
  /**
   * @dev Emitted when the pause is triggered by `account`.
   */
  event Paused(address account);

  /**
   * @dev Emitted when the pause is lifted by `account`.
   */
  event Unpaused(address account);

  bool private _paused;

  /**
   * @dev Initializes the contract in unpaused state.
   */
  constructor() {
    _paused = false;
  }

  /**
   * @dev Modifier to make a function callable only when the contract is not paused.
   *
   * Requirements:
   *
   * - The contract must not be paused.
   */
  modifier whenNotPaused() {
    _requireNotPaused();
    _;
  }

  /**
   * @dev Modifier to make a function callable only when the contract is paused.
   *
   * Requirements:
   *
   * - The contract must be paused.
   */
  modifier whenPaused() {
    _requirePaused();
    _;
  }

  /**
   * @dev Returns true if the contract is paused, and false otherwise.
   */
  function paused() public view virtual returns (bool) {
    return _paused;
  }

  /**
   * @dev Throws if the contract is paused.
   */
  function _requireNotPaused() internal view virtual {
    require(!paused(), "Pausable: paused");
  }

  /**
   * @dev Throws if the contract is not paused.
   */
  function _requirePaused() internal view virtual {
    require(paused(), "Pausable: not paused");
  }

  /**
   * @dev Triggers stopped state.
   *
   * Requirements:
   *
   * - The contract must not be paused.
   */
  function _pause() internal virtual whenNotPaused {
    _paused = true;
    emit Paused(_msgSender());
  }

  /**
   * @dev Returns to normal state.
   *
   * Requirements:
   *
   * - The contract must be paused.
   */
  function _unpause() internal virtual whenPaused {
    _paused = false;
    emit Unpaused(_msgSender());
  }
}


// File contracts/interfaces/IERC20.sol

pragma solidity ^0.8.0;

interface IERC20 {
  /**
   * @dev Returns the amount of tokens in existence.
   */
  function totalSupply() external view returns (uint256);

  /**
   * @dev Returns the token decimals.
   */
  function decimals() external view returns (uint8);

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

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

  /**
   * @dev Returns the bep token owner.
   */
  function getOwner() external view returns (address);

  /**
   * @dev Returns the amount of tokens owned by `account`.
   */
  function balanceOf(address account) external view returns (uint256);

  /**
   * @dev Moves `amount` tokens from the caller's account to `recipient`.
   *
   * Returns a boolean value indicating whether the operation succeeded.
   *
   * Emits a {Transfer} event.
   */
  function transfer(address recipient, uint256 amount) 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 `amount` 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 amount) external returns (bool);

  /**
   * @dev Moves `amount` tokens from `sender` to `recipient` using the
   * allowance mechanism. `amount` is then deducted from the caller's
   * allowance.
   *
   * Returns a boolean value indicating whether the operation succeeded.
   *
   * Emits a {Transfer} event.
   */
  function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);

  /**
   * @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);
}


// File contracts/libs/Address.sol

pragma solidity ^0.8.18;

/**
 * @dev Collection of functions related to the address type
 */
library Address {
  /**
   * @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/v0.8.0/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 functionCallWithValue(target, data, 0, "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");
    (bool success, bytes memory returndata) = target.call{value: value}(data);
    return verifyCallResultFromTarget(target, 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) {
    (bool success, bytes memory returndata) = target.staticcall(data);
    return verifyCallResultFromTarget(target, 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) {
    (bool success, bytes memory returndata) = target.delegatecall(data);
    return verifyCallResultFromTarget(target, success, returndata, errorMessage);
  }

  /**
   * @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
   * the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
   *
   * _Available since v4.8._
   */
  function verifyCallResultFromTarget(
    address target,
    bool success,
    bytes memory returndata,
    string memory errorMessage
  ) internal view returns (bytes memory) {
    if (success) {
      if (returndata.length == 0) {
        // 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
        require(target.code.length > 0, "Address: call to non-contract");
      }
      return returndata;
    } else {
      _revert(returndata, errorMessage);
    }
  }

  /**
   * @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
   * revert reason or 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 {
      _revert(returndata, errorMessage);
    }
  }

  function _revert(bytes memory returndata, string memory errorMessage) 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(errorMessage);
    }
  }
}


// File contracts/libs/SafeERC20.sol

pragma solidity ^0.8.18;


/**
 * @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 contracts/libs/ReentrancyGuard.sol

pragma solidity ^0.8.18;

/**
 * @dev Contract module that helps prevent reentrant calls to a function.
 *
 * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
 * available, which can be applied to functions to make sure there are no nested
 * (reentrant) calls to them.
 *
 * Note that because there is a single `nonReentrant` guard, functions marked as
 * `nonReentrant` may not call one another. This can be worked around by making
 * those functions `private`, and then adding `external` `nonReentrant` entry
 * points to them.
 *
 * TIP: If you would like to learn more about reentrancy and alternative ways
 * to protect against it, check out our blog post
 * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
 */
abstract contract ReentrancyGuard {
  // Booleans are more expensive than uint256 or any type that takes up a full
  // word because each write operation emits an extra SLOAD to first read the
  // slot's contents, replace the bits taken up by the boolean, and then write
  // back. This is the compiler's defense against contract upgrades and
  // pointer aliasing, and it cannot be disabled.

  // The values being non-zero value makes deployment a bit more expensive,
  // but in exchange the refund on every call to nonReentrant will be lower in
  // amount. Since refunds are capped to a percentage of the total
  // transaction's gas, it is best to keep them low in cases like this one, to
  // increase the likelihood of the full refund coming into effect.
  uint256 private constant _NOT_ENTERED = 1;
  uint256 private constant _ENTERED = 2;

  uint256 private _status;

  constructor() {
    _status = _NOT_ENTERED;
  }

  /**
   * @dev Prevents a contract from calling itself, directly or indirectly.
   * Calling a `nonReentrant` function from another `nonReentrant`
   * function is not supported. It is possible to prevent this from happening
   * by making the `nonReentrant` function external, and making it call a
   * `private` function that does the actual work.
   */
  modifier nonReentrant() {
    _nonReentrantBefore();
    _;
    _nonReentrantAfter();
  }

  function _nonReentrantBefore() private {
    // On the first call to nonReentrant, _status will be _NOT_ENTERED
    require(_status != _ENTERED, "ReentrancyGuard: reentrant call");

    // Any calls to nonReentrant after this point will fail
    _status = _ENTERED;
  }

  function _nonReentrantAfter() private {
    // By storing the original value once again, a refund is triggered (see
    // https://eips.ethereum.org/EIPS/eip-2200)
    _status = _NOT_ENTERED;
  }

  /**
   * @dev Returns true if the reentrancy guard is currently set to "entered", which indicates there is a
   * `nonReentrant` function in the call stack.
   */
  function _reentrancyGuardEntered() internal view returns (bool) {
    return _status == _ENTERED;
  }
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.18;

contract TokenPreSale is Pausable, ReentrancyGuard, Ownable {
  using SafeERC20 for IERC20;
  using Address for address payable;

  // uint256 public CLAIM_INTERVAL = 2592000;
  uint256 public round;
  bool public isOpenPublic; // change from private sale to public pre sale

  IERC20 public saleToken;
  address public receiverEth;
  address[] private idoUsers;

  struct Presale {
    uint256 presaleStartTime;
    uint256 presaleEndTime;
    uint256 priceRate;
    uint256 maxTokensToSell;
    uint256 inSale;
    uint256 vestingStartTime;
    uint256 totalVestingMonths;
    uint256 unlockPercentage;
    uint256 remainingPercentage;
  }

  struct Vesting {
    address buyer;
    uint256 maxPurchasable;
    uint256 totalAmount;
    // uint256 claimedAmount;
    // uint256 balance;
    // uint256 cliffDuration;
  }

  mapping(uint256 => Presale) public presaleRound;
  mapping(address => Vesting) public usersVesting;

  event PresaleUpdated(uint256 prevValue, uint256 newValue, uint256 timestamp);
  event UnlockPreSale(bool isOpenPresale, uint256 timestamp);
  // event TokensClaimed(address indexed account, uint256 indexed id, uint256 amount, uint256 timestamp);
  event TokensBought(address indexed account, uint256 tokensBought, uint256 timestamp);
  event ReceivedEther(address indexed account, uint256 amount);
  // event Claim(address indexed account, uint256 amount);
  event WithdrawPool(address indexed recipient, uint256 amount);
  event PresalePaused(uint256 timestamp);
  event PresaleUnpaused(uint256 timestamp);

  error SaleTokenInvalid(address saleToken);
  // error LessPayment();
  error OverLimited();
  error InvalidTimeBuy();

  constructor(
    address initialOwner,
    address _receiverEth,
    // uint256 _maxTokensToSell,
    // uint256 _totalVestingMonths,
    // uint256 _unlockPercentage,
    // uint256 _remainingPercentage,
    uint256 _priceRate
  ) Ownable(initialOwner) {
    // require(_maxTokensToSell > 0, "amount tokens to sell must be greater than 0");

    // Make this contract initialized
    receiverEth = _receiverEth;
    uint256 PRECISION_FACTOR = uint256(10 ** (uint256(30) - uint256(18)));

    // init presale
    Presale storage presale = presaleRound[round];

    presale.priceRate = _priceRate * PRECISION_FACTOR;
    // presale.maxTokensToSell = _maxTokensToSell;
    // presale.inSale = _maxTokensToSell;
    // presale.totalVestingMonths = _totalVestingMonths;
    // presale.unlockPercentage = _unlockPercentage;
    // presale.remainingPercentage = _remainingPercentage;
  }

  function getAllUsersVesting() external view returns (Vesting[] memory) {
    Vesting[] memory usersVestingInfo = new Vesting[](idoUsers.length);

    for (uint256 i = 0; i < idoUsers.length; i++) {
        usersVestingInfo[i] = usersVesting[idoUsers[i]];
    }

    return usersVestingInfo;
  }

  /**
   * @dev To update the vesting start time
   * @param _vestingStartTime New vesting start time
   */
  // function changeVestingStartTime(uint256 _vestingStartTime) external onlyOwner {
  //   Presale storage presale = presaleRound[round];

  //   require(presale.presaleEndTime > 0, "Presale have not started");
  //   require(_vestingStartTime >= presale.presaleEndTime, "Vesting starts before Presale ends");

  //   uint256 prevValue = presale.vestingStartTime;
  //   presale.vestingStartTime = _vestingStartTime;

  //   emit PresaleUpdated(prevValue, _vestingStartTime, block.timestamp);
  // }

  /**
   * @dev To update the presale price rate
   * @param _priceRate New price rate
   */
  function changePriceRate(uint256 _priceRate) external onlyOwner {
    Presale storage presale = presaleRound[round];

    require(presale.presaleEndTime > 0, "Presale have not started");
    require(_priceRate > 0, "IDOPreSale: price rate invalid");

    uint256 prevValue = presale.priceRate;
    presale.priceRate = _priceRate;

    emit PresaleUpdated(prevValue, _priceRate, block.timestamp);
  }

  /**
   * @dev To update the presale start time
   * @param _presaleStartTime New presale start time
   * @param _presaleEndTime New presale end time
   */
  function setPresaleTime(uint256 _presaleStartTime, uint256 _presaleEndTime) external onlyOwner {
    require(block.timestamp < _presaleStartTime && _presaleStartTime <= _presaleEndTime, "Invalid timestamp");

    Presale storage presale = presaleRound[round];
    uint256 prevValue = presale.presaleStartTime;
    presale.presaleStartTime = _presaleStartTime;
    presale.presaleEndTime = _presaleEndTime;

    emit PresaleUpdated(prevValue, _presaleStartTime, _presaleEndTime);
  }

  function setSaleToken(IERC20 _saleToken) external onlyOwner {
    require(address(_saleToken) != address(0), "IDO: sale token is zero address");
    saleToken = _saleToken;
  }

  function setReceiver(address _receiverEth) external onlyOwner {
    require(_receiverEth != address(0), "IDO: sale token is zero address");
    receiverEth = _receiverEth;
  }

  /**
   * @dev To update the private sale to pre sale
   */
  function setUnlockPublicSale() external onlyOwner {
    isOpenPublic = !isOpenPublic;

    emit UnlockPreSale(isOpenPublic, block.timestamp);
  }

  /**
   * @dev To pause the presale
   */
  function pausePresale() external onlyOwner {
    super._pause();
    emit PresalePaused(block.timestamp);
  }

  /**
   * @dev To unpause the presale
   */
  function unPausePresale() external onlyOwner {
    super._unpause();
    emit PresaleUnpaused(block.timestamp);
  }

  function purchaseWithEth() external payable nonReentrant whenNotPaused {
    Presale storage presale = presaleRound[round];
    uint256 maxPurchasable = usersVesting[_msgSender()].maxPurchasable + msg.value;

    if (block.timestamp <= presale.presaleStartTime || block.timestamp >= presale.presaleEndTime) {
      revert InvalidTimeBuy();
    }

    // if (maxPurchasable > 50 ether) {
    //   revert OverLimited();
    // }

    // uint256 minimumEther = 0.002 * 10 ** 18;
    uint256 amount = msg.value * presale.priceRate;
    uint256 PRECISION_FACTOR = uint256(10 ** (uint256(30) - uint256(18)));

    amount = amount / PRECISION_FACTOR;
    presale.inSale += amount;

    // if (msg.value < minimumEther) {
    //   revert LessPayment();
    // }

    // if(presale.inSale == 0) {
    //   presale.presaleEndTime = block.timestamp;
    // }

    if (usersVesting[_msgSender()].totalAmount > 0) {
      usersVesting[_msgSender()].totalAmount += amount;
      // usersVesting[_msgSender()].balance = usersVesting[_msgSender()].totalAmount;
      usersVesting[_msgSender()].maxPurchasable = maxPurchasable;
    } else {
      usersVesting[_msgSender()] = Vesting({
        buyer: _msgSender(),
        maxPurchasable: maxPurchasable,
        totalAmount: amount
        // claimedAmount: 0,
        // balance: amount,
        // cliffDuration: CLAIM_INTERVAL
      });

      idoUsers.push(_msgSender());
    }

    // payable(receiverEth).sendValue(msg.value);

    emit TokensBought(_msgSender(), amount, block.timestamp);
  }

  function emergencyWithdrawETH(address payable recipient, uint256 amount) public onlyOwner {
    require(recipient != address(0), "recipient: recipient ether is the zero address");
    require(amount > 0, "Ether amount is zero");
    require(address(this).balance >= amount, "Not enough funds");

    // Effects
    uint256 balanceBeforeTransfer = address(this).balance;

    // Interactions
    (bool success, ) = recipient.call{value: amount}("");
    require(success, "ETH Payment failed");

    // Verify balance reduced correctly (optional safety check)
    assert(address(this).balance == balanceBeforeTransfer - amount);

    emit WithdrawPool(recipient, amount);
  }

  function emergencyWithdraw(address recipient, uint256 _amount) public onlyOwner {
    if (address(saleToken) == address(0)) {
      revert SaleTokenInvalid(address(0));
    }

    require(recipient != address(0), "recipient: recipient ether is the zero address");
    require(_amount > 0, "ERC20: amount is zero");
    require(saleToken.balanceOf(address(this)) >= _amount, "insufficient balance");

    saleToken.safeTransfer(recipient, _amount);

    emit WithdrawPool(recipient, _amount);
  }

  // function claimableBalace(address account) public view returns (uint256 claimable) {
  //   Vesting memory userVesting = usersVesting[account];
  //   Presale memory presale = presaleRound[round];

  //   if (
  //     userVesting.balance == 0 ||
  //     presale.unlockPercentage == 0 ||
  //     presale.vestingStartTime > block.timestamp
  //   ) {
  //     return 0;
  //   }

  //   uint256 elapsedTime = block.timestamp - presale.vestingStartTime;

  //   if (elapsedTime < userVesting.cliffDuration) {
  //     claimable = (userVesting.totalAmount * presale.unlockPercentage) / 10000;
  //   } else {
  //     uint256 remainingMonths = (CLAIM_INTERVAL + elapsedTime - userVesting.cliffDuration) / CLAIM_INTERVAL;
  //     uint256 remainingPercentageForMonth = presale.remainingPercentage / presale.totalVestingMonths;
  //     claimable = (userVesting.totalAmount * remainingMonths * remainingPercentageForMonth) / 10000;
  //     claimable += (userVesting.totalAmount * presale.unlockPercentage) / 10000; // Add the cliff claimable amount
  //   }

  //   claimable -= userVesting.claimedAmount;

  //   if (claimable > userVesting.balance) {
  //     claimable = userVesting.balance;
  //   }
  // }

  // function nextClaimTime(address account) public view returns (uint256 nextTime, uint256 amount) {
  //   nextTime = 0;
  //   amount = 0;

  //   Vesting memory userVesting = usersVesting[account];
  //   Presale memory presale = presaleRound[round];

  //   if (
  //     userVesting.balance == 0 ||
  //     presale.unlockPercentage == 0 ||
  //     presale.remainingPercentage == 0 ||
  //     CLAIM_INTERVAL == 0
  //   ) {
  //     return (nextTime, amount);
  //   }

  //   uint256 lockedAmount = userVesting.balance - claimableBalace(account);
  //   uint256 elapsedTime = block.timestamp < presale.vestingStartTime ? 0 : block.timestamp - presale.vestingStartTime;
  //   uint256 remainingPercentageForMonth = presale.remainingPercentage / presale.totalVestingMonths;

  //   if (block.timestamp < presale.vestingStartTime) {
  //     amount = (userVesting.totalAmount * presale.unlockPercentage) / 10000;
  //   } else {
  //     amount = (userVesting.totalAmount * remainingPercentageForMonth) / 10000;
  //   }

  //   if (lockedAmount < amount) {
  //     amount = lockedAmount;
  //   }

  //   if (amount > 0) {
  //     if (block.timestamp < presale.vestingStartTime) {
  //       nextTime = presale.vestingStartTime;
  //     } else {
  //       nextTime = (elapsedTime / CLAIM_INTERVAL) + 1;
  //       nextTime = (nextTime * CLAIM_INTERVAL) + presale.vestingStartTime;
  //     }
  //   }
  // }

  // function claimAll() external nonReentrant whenNotPaused {
  //   uint256 claimable = claimableBalace(msg.sender);
  //   _claim(claimable);
  // }

  // function claim(uint256 _amount) external nonReentrant whenNotPaused {
  //   require(claimableBalace(msg.sender) >= _amount, "insufficient balance");
  //   _claim(_amount);
  // }

  // function _claim(uint256 _amount) internal {
  //   if (address(saleToken) == address(0)) {
  //     revert SaleTokenInvalid(address(0));
  //   }

  //   require(_amount > 0, "you don't have enough claimable amount");
  //   require(saleToken.balanceOf(address(this)) >= _amount, "insufficient balance");

  //   Vesting storage userVesting = usersVesting[msg.sender];

  //   unchecked {
  //     // Overflow not possible: amount < user balance
  //     userVesting.balance = userVesting.balance - _amount;
  //     userVesting.claimedAmount = userVesting.claimedAmount + _amount;
  //   }

  //   saleToken.safeTransfer(msg.sender, _amount);

  //   emit Claim(msg.sender, _amount);
  // }

  function balanceOf(address account) public view returns (uint256) {
    Vesting memory userVesting = usersVesting[account];
    return userVesting.totalAmount;
  }

  receive() external payable {
    emit ReceivedEther(msg.sender, msg.value);
  }
}