creation_sourcecode: // SPDX-License-Identifier: MIT
  // File: @openzeppelin/contracts/token/ERC20/IERC20.sol
  
  
  // 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: @openzeppelin/contracts/token/ERC20/extensions/IERC20Metadata.sol
  
  
  // OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/extensions/IERC20Metadata.sol)
  
  pragma solidity ^0.8.20;
  
  
  /**
   * @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: @openzeppelin/contracts/utils/structs/EnumerableSet.sol
  
  
  // OpenZeppelin Contracts (last updated v5.0.0) (utils/structs/EnumerableSet.sol)
  // This file was procedurally generated from scripts/generate/templates/EnumerableSet.js.
  
  pragma solidity ^0.8.20;
  
  /**
   * @dev Library for managing
   * https://en.wikipedia.org/wiki/Set_(abstract_data_type)[sets] of primitive
   * types.
   *
   * Sets have the following properties:
   *
   * - Elements are added, removed, and checked for existence in constant time
   * (O(1)).
   * - Elements are enumerated in O(n). No guarantees are made on the ordering.
   *
   * ```solidity
   * contract Example {
   *     // Add the library methods
   *     using EnumerableSet for EnumerableSet.AddressSet;
   *
   *     // Declare a set state variable
   *     EnumerableSet.AddressSet private mySet;
   * }
   * ```
   *
   * As of v3.3.0, sets of type `bytes32` (`Bytes32Set`), `address` (`AddressSet`)
   * and `uint256` (`UintSet`) are supported.
   *
   * [WARNING]
   * ====
   * Trying to delete such a structure from storage will likely result in data corruption, rendering the structure
   * unusable.
   * See https://github.com/ethereum/solidity/pull/11843[ethereum/solidity#11843] for more info.
   *
   * In order to clean an EnumerableSet, you can either remove all elements one by one or create a fresh instance using an
   * array of EnumerableSet.
   * ====
   */
  library EnumerableSet {
      // To implement this library for multiple types with as little code
      // repetition as possible, we write it in terms of a generic Set type with
      // bytes32 values.
      // The Set implementation uses private functions, and user-facing
      // implementations (such as AddressSet) are just wrappers around the
      // underlying Set.
      // This means that we can only create new EnumerableSets for types that fit
      // in bytes32.
  
      struct Set {
          // Storage of set values
          bytes32[] _values;
          // Position is the index of the value in the `values` array plus 1.
          // Position 0 is used to mean a value is not in the set.
          mapping(bytes32 value => uint256) _positions;
      }
  
      /**
       * @dev Add a value to a set. O(1).
       *
       * Returns true if the value was added to the set, that is if it was not
       * already present.
       */
      function _add(Set storage set, bytes32 value) private returns (bool) {
          if (!_contains(set, value)) {
              set._values.push(value);
              // The value is stored at length-1, but we add 1 to all indexes
              // and use 0 as a sentinel value
              set._positions[value] = set._values.length;
              return true;
          } else {
              return false;
          }
      }
  
      /**
       * @dev Removes a value from a set. O(1).
       *
       * Returns true if the value was removed from the set, that is if it was
       * present.
       */
      function _remove(Set storage set, bytes32 value) private returns (bool) {
          // We cache the value's position to prevent multiple reads from the same storage slot
          uint256 position = set._positions[value];
  
          if (position != 0) {
              // Equivalent to contains(set, value)
              // To delete an element from the _values array in O(1), we swap the element to delete with the last one in
              // the array, and then remove the last element (sometimes called as 'swap and pop').
              // This modifies the order of the array, as noted in {at}.
  
              uint256 valueIndex = position - 1;
              uint256 lastIndex = set._values.length - 1;
  
              if (valueIndex != lastIndex) {
                  bytes32 lastValue = set._values[lastIndex];
  
                  // Move the lastValue to the index where the value to delete is
                  set._values[valueIndex] = lastValue;
                  // Update the tracked position of the lastValue (that was just moved)
                  set._positions[lastValue] = position;
              }
  
              // Delete the slot where the moved value was stored
              set._values.pop();
  
              // Delete the tracked position for the deleted slot
              delete set._positions[value];
  
              return true;
          } else {
              return false;
          }
      }
  
      /**
       * @dev Returns true if the value is in the set. O(1).
       */
      function _contains(Set storage set, bytes32 value) private view returns (bool) {
          return set._positions[value] != 0;
      }
  
      /**
       * @dev Returns the number of values on the set. O(1).
       */
      function _length(Set storage set) private view returns (uint256) {
          return set._values.length;
      }
  
      /**
       * @dev Returns the value stored at position `index` in the set. O(1).
       *
       * Note that there are no guarantees on the ordering of values inside the
       * array, and it may change when more values are added or removed.
       *
       * Requirements:
       *
       * - `index` must be strictly less than {length}.
       */
      function _at(Set storage set, uint256 index) private view returns (bytes32) {
          return set._values[index];
      }
  
      /**
       * @dev Return the entire set in an array
       *
       * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
       * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
       * this function has an unbounded cost, and using it as part of a state-changing function may render the function
       * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
       */
      function _values(Set storage set) private view returns (bytes32[] memory) {
          return set._values;
      }
  
      // Bytes32Set
  
      struct Bytes32Set {
          Set _inner;
      }
  
      /**
       * @dev Add a value to a set. O(1).
       *
       * Returns true if the value was added to the set, that is if it was not
       * already present.
       */
      function add(Bytes32Set storage set, bytes32 value) internal returns (bool) {
          return _add(set._inner, value);
      }
  
      /**
       * @dev Removes a value from a set. O(1).
       *
       * Returns true if the value was removed from the set, that is if it was
       * present.
       */
      function remove(Bytes32Set storage set, bytes32 value) internal returns (bool) {
          return _remove(set._inner, value);
      }
  
      /**
       * @dev Returns true if the value is in the set. O(1).
       */
      function contains(Bytes32Set storage set, bytes32 value) internal view returns (bool) {
          return _contains(set._inner, value);
      }
  
      /**
       * @dev Returns the number of values in the set. O(1).
       */
      function length(Bytes32Set storage set) internal view returns (uint256) {
          return _length(set._inner);
      }
  
      /**
       * @dev Returns the value stored at position `index` in the set. O(1).
       *
       * Note that there are no guarantees on the ordering of values inside the
       * array, and it may change when more values are added or removed.
       *
       * Requirements:
       *
       * - `index` must be strictly less than {length}.
       */
      function at(Bytes32Set storage set, uint256 index) internal view returns (bytes32) {
          return _at(set._inner, index);
      }
  
      /**
       * @dev Return the entire set in an array
       *
       * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
       * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
       * this function has an unbounded cost, and using it as part of a state-changing function may render the function
       * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
       */
      function values(Bytes32Set storage set) internal view returns (bytes32[] memory) {
          bytes32[] memory store = _values(set._inner);
          bytes32[] memory result;
  
          /// @solidity memory-safe-assembly
          assembly {
              result := store
          }
  
          return result;
      }
  
      // AddressSet
  
      struct AddressSet {
          Set _inner;
      }
  
      /**
       * @dev Add a value to a set. O(1).
       *
       * Returns true if the value was added to the set, that is if it was not
       * already present.
       */
      function add(AddressSet storage set, address value) internal returns (bool) {
          return _add(set._inner, bytes32(uint256(uint160(value))));
      }
  
      /**
       * @dev Removes a value from a set. O(1).
       *
       * Returns true if the value was removed from the set, that is if it was
       * present.
       */
      function remove(AddressSet storage set, address value) internal returns (bool) {
          return _remove(set._inner, bytes32(uint256(uint160(value))));
      }
  
      /**
       * @dev Returns true if the value is in the set. O(1).
       */
      function contains(AddressSet storage set, address value) internal view returns (bool) {
          return _contains(set._inner, bytes32(uint256(uint160(value))));
      }
  
      /**
       * @dev Returns the number of values in the set. O(1).
       */
      function length(AddressSet storage set) internal view returns (uint256) {
          return _length(set._inner);
      }
  
      /**
       * @dev Returns the value stored at position `index` in the set. O(1).
       *
       * Note that there are no guarantees on the ordering of values inside the
       * array, and it may change when more values are added or removed.
       *
       * Requirements:
       *
       * - `index` must be strictly less than {length}.
       */
      function at(AddressSet storage set, uint256 index) internal view returns (address) {
          return address(uint160(uint256(_at(set._inner, index))));
      }
  
      /**
       * @dev Return the entire set in an array
       *
       * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
       * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
       * this function has an unbounded cost, and using it as part of a state-changing function may render the function
       * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
       */
      function values(AddressSet storage set) internal view returns (address[] memory) {
          bytes32[] memory store = _values(set._inner);
          address[] memory result;
  
          /// @solidity memory-safe-assembly
          assembly {
              result := store
          }
  
          return result;
      }
  
      // UintSet
  
      struct UintSet {
          Set _inner;
      }
  
      /**
       * @dev Add a value to a set. O(1).
       *
       * Returns true if the value was added to the set, that is if it was not
       * already present.
       */
      function add(UintSet storage set, uint256 value) internal returns (bool) {
          return _add(set._inner, bytes32(value));
      }
  
      /**
       * @dev Removes a value from a set. O(1).
       *
       * Returns true if the value was removed from the set, that is if it was
       * present.
       */
      function remove(UintSet storage set, uint256 value) internal returns (bool) {
          return _remove(set._inner, bytes32(value));
      }
  
      /**
       * @dev Returns true if the value is in the set. O(1).
       */
      function contains(UintSet storage set, uint256 value) internal view returns (bool) {
          return _contains(set._inner, bytes32(value));
      }
  
      /**
       * @dev Returns the number of values in the set. O(1).
       */
      function length(UintSet storage set) internal view returns (uint256) {
          return _length(set._inner);
      }
  
      /**
       * @dev Returns the value stored at position `index` in the set. O(1).
       *
       * Note that there are no guarantees on the ordering of values inside the
       * array, and it may change when more values are added or removed.
       *
       * Requirements:
       *
       * - `index` must be strictly less than {length}.
       */
      function at(UintSet storage set, uint256 index) internal view returns (uint256) {
          return uint256(_at(set._inner, index));
      }
  
      /**
       * @dev Return the entire set in an array
       *
       * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
       * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
       * this function has an unbounded cost, and using it as part of a state-changing function may render the function
       * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
       */
      function values(UintSet storage set) internal view returns (uint256[] memory) {
          bytes32[] memory store = _values(set._inner);
          uint256[] memory result;
  
          /// @solidity memory-safe-assembly
          assembly {
              result := store
          }
  
          return result;
      }
  }
  
  // File: @openzeppelin/contracts/utils/Context.sol
  
  
  // OpenZeppelin Contracts (last updated v5.0.1) (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;
      }
  
      function _contextSuffixLength() internal view virtual returns (uint256) {
          return 0;
      }
  }
  
  // File: @openzeppelin/contracts/security/Pausable.sol
  
  
  // OpenZeppelin Contracts (last updated v4.7.0) (security/Pausable.sol)
  
  pragma solidity ^0.8.0;
  
  
  /**
   * @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: @openzeppelin/contracts/security/ReentrancyGuard.sol
  
  
  // OpenZeppelin Contracts (last updated v4.9.0) (security/ReentrancyGuard.sol)
  
  pragma solidity ^0.8.0;
  
  /**
   * @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;
      }
  }
  
  // File: @openzeppelin/contracts/access/Ownable.sol
  
  
  // OpenZeppelin Contracts (last updated v5.0.0) (access/Ownable.sol)
  
  pragma solidity ^0.8.20;
  
  
  /**
   * @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: @openzeppelin/contracts/token/ERC20/extensions/IERC20Permit.sol
  
  
  // 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: @openzeppelin/contracts/utils/Address.sol
  
  
  // 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: @openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol
  
  
  // OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/utils/SafeERC20.sol)
  
  pragma solidity ^0.8.20;
  
  
  
  
  /**
   * @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: Presale.sol
  
  
  pragma solidity ^0.8.9;
  
  
  
  
  
  
  
  contract Presale is Pausable, Ownable, ReentrancyGuard {
      using EnumerableSet for EnumerableSet.AddressSet;
      using SafeERC20 for IERC20Metadata;
  
      uint256 public constant PERCENTAGE_DENOMINATOR = 10000;
      uint256 public constant TOTAL_MAX_ALLOCATION = 1500000000 * 10 ** 18;
      uint256 public ethUSD;
  
      uint256 public ogRoundTokenLimited;
      uint256 public publicRoundTokenLimited;
  
      uint256 public pricePerToken;
      uint8 public tokenDecimals;
      uint8 public nativeDecimals;
  
      uint256 public ogRoundStartedAt;
      uint256 public publicRoundStartedAt;
  
      uint256 public ogRoundDuration;
      uint256 public publicRoundDuration;
  
      bool public isOGRound;
      bool public isPublicRound;
      mapping(address => bool) public ogWhitelist;
      mapping(address => uint256) public ogWhitelistTokenlimited;
  
      EnumerableSet.AddressSet allBuyerList; /// wallet history who purchased and requested tokens.
  
      mapping(address => uint256) public tokensRequested;
      mapping(address => bool) public isBonusRequested;
      mapping(address => uint256) public bonusRequested;
  
      IERC20Metadata public token;
      IERC20Metadata public usdc;
      IERC20Metadata public usdt;
  
      uint256 public totalTokensRequested;
  
      uint256 public presaleExpireTime;
  
      uint256 public bonusPercent;
      uint256 public fundsRaised;
  
      mapping(string => address) public referrersWithRefCodes; // refCode => referrer;
      mapping(address => mapping(address => bool)) public hasReferred; // referrer => referee => bool
  
      mapping(address => bool) public isReferrer; // referrer => bool;
  
      mapping(address => bool) public isUsedRefCode; // referee => bool;
  
      mapping(address => uint256) public refereeCount; // referrer => referee count
      mapping(string => uint256) public numOfReferee; // referrer ref code => referee count;
      mapping(string => uint256) public refereeAmount; // referrer => referred amount;
      
      address public fundingWallet;
  
      constructor(
          address _usdc,
          address _usdt,
          address _fundingWallet
      ) Ownable(msg.sender){
          pricePerToken = 800; // 0.0008 USD
  
          usdc = IERC20Metadata(_usdc);
          usdt = IERC20Metadata(_usdt);
  
          bonusPercent = 500;
  
          ogRoundDuration = 3600; // 1 hour
          publicRoundDuration = 169200; // 47 hours
  
          isOGRound = false;
          isPublicRound = false;
  
          tokenDecimals = 18;
          nativeDecimals = usdc.decimals();
  
          ethUSD = 3680 * 10 ** 6; // 3680 USD
  
          publicRoundTokenLimited = 12500000 * 10 ** tokenDecimals;
  
          fundingWallet = _fundingWallet;
      }
  
  
      /// @notice pause the presale
      function pause() public onlyOwner {
          _pause();
      }
  
      /// @notice unpause the presale
      function unpause() public onlyOwner {
          _unpause();
      }
  
      /// @notice get the presale data
      /// @return the price, hard limit, duration and hold limit
      function data() external view returns (uint256, uint256) {
          return (pricePerToken, publicRoundTokenLimited);
      }
  
      function setStartOGRound() external onlyOwner {
          isOGRound = true;
          ogRoundStartedAt = block.timestamp;
          isPublicRound = false;
      }
  
      function setStartPublicRound() external onlyOwner {
          isPublicRound = true;
          publicRoundStartedAt = block.timestamp;
          isOGRound = false;
      }
  
      function endOGRound() public onlyOwner {
          if (isOGRound) {
              isOGRound = false;
          }
      }
  
      function endPublicRound() public onlyOwner {
          if (isPublicRound) {
              isPublicRound = false;
          }
      }
  
      function setOGRoundDuration(uint256 _duration) external onlyOwner {
          ogRoundDuration = _duration;
      }
  
      function setPublicRoundDuration(uint256 _duration) external onlyOwner {
          publicRoundDuration = _duration;
      }
  
      function setOGRoundTokenLimited(
          address[] memory _whitelisted,
          uint256[] memory _ogRoundTokenLimited
      ) external onlyOwner {
          for (uint256 i = 0; i < _whitelisted.length; ++i) {
              if (ogWhitelist[_whitelisted[i]] == true) {
                  ogWhitelistTokenlimited[_whitelisted[i]] = _ogRoundTokenLimited[i];
              }
          }
      }
  
      function setOGRoundSingleTokenLimited(
          address[] memory _whitelisted,
          uint256 _ogRoundTokenLimited
      ) external onlyOwner {
          for (uint256 i = 0; i < _whitelisted.length; ++i) {
              if (ogWhitelist[_whitelisted[i]] == true) {
                  ogWhitelistTokenlimited[_whitelisted[i]] = _ogRoundTokenLimited;
              }
          }
      }
  
      function setPublicRoundTokenLimited(uint256 _publicRoundTokenLimited) external onlyOwner {
          publicRoundTokenLimited = _publicRoundTokenLimited;
      }
  
      function setPresaleToken(address _token) external onlyOwner {
          require(_token != address(0), "Token shouldn't be zero");
          token = IERC20Metadata(_token);
          tokenDecimals = token.decimals();
      }
  
      function setUSDCToken(address _usdc) external onlyOwner {
          require(_usdc != address(0), "USDC shouldn't be zero");
          usdc = IERC20Metadata(_usdc);
          nativeDecimals = usdc.decimals();
      }
  
      function setUSDTToken(address _usdt) external onlyOwner {
          require(_usdt != address(0), "USDT shouldn't be zero");
          usdt = IERC20Metadata(_usdt);
          nativeDecimals = usdt.decimals();
      }
  
      function setFundingWallet(address _fundingWallet) external onlyOwner {
          require(_fundingWallet != address(0), "Funding Wallet shouldn't be zero");
          fundingWallet = _fundingWallet;
      }
  
      function setBonusPercent(uint256 _rate) external onlyOwner {
          require(_rate >= 100 && _rate < PERCENTAGE_DENOMINATOR, "Rate should be less than 100%");
          bonusPercent = _rate;
      }
  
      /// @notice set the price of the token
      /// @param _pricePerToken the price per token
      function setPrice(uint256 _pricePerToken) external onlyOwner {
          pricePerToken = _pricePerToken;
      }
  
      function setETHUSDPrice(uint256 _ethUSD) external onlyOwner {
          ethUSD = _ethUSD * 10 * nativeDecimals;
      }
  
      /// @notice withdraw tokens stored in the contract
      function withdrawTokens(address _token, address _to, uint256 _amount) external onlyOwner {
          IERC20Metadata(_token).safeTransfer(_to, _amount);
      }
  
      /// @notice withdraw usdc stored in the contract
      function withdrawUSDC(address _to) external onlyOwner {
          usdc.safeTransfer(_to, usdc.balanceOf(address(this)));
      }
  
      function withdrawUSDT(address _to) external onlyOwner {
          usdt.safeTransfer(_to, usdt.balanceOf(address(this)));
      }
  
      function registerToOGWhitelist(address[] memory _accounts) external onlyOwner {
          for (uint256 i = 0; i < _accounts.length; ++i) {
              ogWhitelist[_accounts[i]] = true;
          }
      }
  
      function removeFromOGWhitelist(address[] memory _accounts) external onlyOwner {
          for (uint256 i = 0; i < _accounts.length; ++i) {
              ogWhitelist[_accounts[i]] = false;
          }
      }
  
      function _isEligibleTokens(address _account, uint256 _value, uint256 _tokenLimit) internal view returns (bool) {
          return tokensRequested[_account] + _value <= _tokenLimit;
      }
  
      function _isValidReferralCode(string memory _refCode) internal view returns (bool) {
          if (bytes(_refCode).length < 5) return false;
          if (referrersWithRefCodes[_refCode] == address(0)) return false;
          return true;
      }
  
      function _isOGRound() internal view returns (bool) {
          return isOGRound && ((ogRoundStartedAt + ogRoundDuration) >= block.timestamp) && (block.timestamp >= ogRoundStartedAt);
      }
  
      function _isPublicRound() internal view returns (bool) {
          return isPublicRound && ((publicRoundStartedAt + publicRoundDuration) >= block.timestamp) && (block.timestamp >= publicRoundStartedAt);
      }
  
      receive() external payable {}
  
      fallback() external {}
  
      function withdrawETH(address _to) external onlyOwner {
          (bool success, ) = payable(_to).call{value: address(this).balance}("");
          if (!success) {
              revert("Transfer Failed");
          }
      }
  
      function _createRefCode(address _referrer, string memory _refCode) internal returns (bool) {
          require(bytes(_refCode).length >= 5, "Invalid Referral Code");
          require(!isReferrer[_referrer] && referrersWithRefCodes[_refCode] == address(0), "You created referral code already");
          referrersWithRefCodes[_refCode] = _referrer;
          isReferrer[_referrer] = true;
          return true;
      }
  
      function deposit(
          uint256 _amount,
          address _referrer,
          string memory _refCode,
          uint256 _chain
      ) external payable nonReentrant whenNotPaused {
          require(_amount > 0, "Not acceptable to require 0 token!");
  
          uint256 tokens = (((_amount * 10 ** tokenDecimals) * 10 ** nativeDecimals) / pricePerToken) / (10 ** nativeDecimals);        
  
          require(totalTokensRequested + tokens <= TOTAL_MAX_ALLOCATION, "More than overall presale allocation!");
  
          if (_referrer != address(0) && !isReferrer[_referrer]) {
              _createRefCode(_referrer, _refCode);
          }
  
          require(referrersWithRefCodes[_refCode] != msg.sender, "You are using your own referral code!");
  
          if (_isOGRound()) {
              require(ogWhitelist[msg.sender], "You have no permission for OG Round!");
              _depositUSDC(msg.sender, _amount, _refCode, ogWhitelistTokenlimited[msg.sender], _chain);
          } else if (_isPublicRound()) {
              _depositUSDC(msg.sender, _amount, _refCode, publicRoundTokenLimited, _chain);
          } else {
              revert("Presale is not allowed!");
          }
  
          if(totalTokensRequested >= TOTAL_MAX_ALLOCATION) {
              endOGRound();
              endPublicRound();
          }
      }
  
      function _depositUSDC(
          address _account,
          uint256 _usdcAmount,
          string memory _refCode,
          uint256 _tokenLimit,
          uint256 _chain
      ) internal returns (bool) {
  
          uint256 tokens = (((_usdcAmount * 10 ** tokenDecimals) * 10 ** nativeDecimals) / pricePerToken) / (10 ** nativeDecimals);
  
          uint256 bonusAmount = (tokens * bonusPercent) / PERCENTAGE_DENOMINATOR;
  
          uint256 ethAmount = (_usdcAmount * 10 ** tokenDecimals) / ethUSD;
          
          if (!_isValidReferralCode(_refCode)) {
              bonusAmount = 0;
          }
  
          if (!_isEligibleTokens(_account, tokens, _tokenLimit)) {
              revert("Account limit exceeded!");
          }
  
          if (tokens == 0) {
              revert("Insufficient token out value");
          }
  
          // based on which chain, USDC = 1, USDT = 2, ETH = 3
          if (_chain == 1) {
              usdc.safeTransferFrom(_account, fundingWallet, _usdcAmount);
          } else if (_chain == 2) {
              usdt.safeTransferFrom(_account, fundingWallet, _usdcAmount);
          } else if (_chain == 3) {
              require(msg.value == ethAmount, "Incorrect ETH amount sent");
              (bool success, ) = payable(fundingWallet).call{value: msg.value}("");
              require(success, "ETH transfer failed");
          } else {
              revert("Invalid chain identifier");
          }
              
          tokensRequested[_account] += tokens;
          totalTokensRequested += tokens;
  
          if (_isValidReferralCode(_refCode)) {
              address referrer = referrersWithRefCodes[_refCode];
              if (referrer != address(0)) {
                  isBonusRequested[_account] = true;
                  bonusRequested[_account] += bonusAmount;
  
                  isBonusRequested[referrer] = true;
                  bonusRequested[referrer] += bonusAmount;
  
                  isUsedRefCode[_account] = true;
                  refereeAmount[_refCode] += _usdcAmount;
              
                  if (!hasReferred[referrer][_account]) {
                      refereeCount[referrer] += 1;
                      numOfReferee[_refCode] += 1;
                      hasReferred[referrer][_account] = true;
                  }
              }
          }
  
          if (!allBuyerList.contains(msg.sender)) {
              allBuyerList.add(msg.sender);
          }
  
          fundsRaised += _usdcAmount;
  
          return true;
      }
  
      /*
       * view functions
       */
  
      function getUSDCForTokens(uint256 _tokensAmount) external view returns (uint256) {
          return (pricePerToken * _tokensAmount) / (10 ** tokenDecimals);
      }
  
      function getBalanceOfUSDC(address _wallet) external view returns (uint256) {
          return usdc.balanceOf(_wallet);
      }
  
      function getTokensRequestedOfWallet(address _account) external view returns (uint256) {
          return tokensRequested[_account];
      }
  
      function getBonusRequested(address _account) external view returns (uint256) {
          return bonusRequested[_account];
      }
  
      function getPricePerToken() external view returns (uint256) {
          return pricePerToken;
      }
  
      function getOGRoundTokenLimited(address _account) external view returns (uint256) {
          return ogWhitelistTokenlimited[_account];
      }
  
      function getPublicRoundTokenLimited() external view returns (uint256) {
          return publicRoundTokenLimited;
      }
  
      function getOGRoundStartedAt() external view returns (uint256) {
          return ogRoundStartedAt;
      }
  
      function getPublicRoundStartedAt() external view returns (uint256) {
          return publicRoundStartedAt;
      }
  
      function getOGRoundDuration() external view returns (uint256) {
          return ogRoundDuration;
      }
  
      function getPublicRoundDuration() external view returns (uint256) {
          return publicRoundDuration;
      }
  
      function getReferreeCount(address _referrer) external view returns (uint256) {
          return refereeCount[_referrer];
      }
  
      function getReferralInfo(string memory _refCode) external view returns (uint256 numOfReferees, uint256 totalRefereeAmount) {
          return (numOfReferee[_refCode], refereeAmount[_refCode]/(10**nativeDecimals));
      }
  
      function getBuyers() external view returns (address[] memory) {
          return allBuyerList.values();
      }
  
      function getBuyerLength() external view returns (uint256) {
          return allBuyerList.length();
      }
  
      function isTokenBuyer(address _account) external view returns (bool) {
          return tokensRequested[_account] > 0;
      }
  
      function isOGWhitelisted(address _account) external view returns (bool) {
          return ogWhitelist[_account];
      }
  
      function checkOGRound() external view returns (bool) {
          return _isOGRound();
      }
  
      function checkPublicRound() external view returns (bool) {
          return _isPublicRound();
      }
  
      function addUsersWithReferralCodes(
          address[] memory _users,
          string[] memory _refCodes
      ) external onlyOwner {
          require(_users.length == _refCodes.length, "Arrays must have the same length");
  
          for (uint256 i = 0; i < _users.length; ++i) {
              require(bytes(_refCodes[i]).length >= 5, "Invalid Referral Code");
              require(!isReferrer[_users[i]], "Referrer already exists");
              require(referrersWithRefCodes[_refCodes[i]] == address(0), "Referral code already used");
  
              referrersWithRefCodes[_refCodes[i]] = _users[i];
              isReferrer[_users[i]] = true;
          }
      }
  
      function updateOldRecords(
          address[] memory users,
          uint256[] memory tokensRequestedList,
          uint256[] memory _bonusRequestedList,
          uint256[] memory refereeCountList,
          uint256 fundsAmount
      ) external onlyOwner {
          require(users.length == tokensRequestedList.length, "Arrays must have the same length");
          require(users.length == _bonusRequestedList.length, "Arrays must have the same length");
          require(users.length == refereeCountList.length, "Arrays must have the same length");
  
          for (uint256 i = 0; i < users.length; i++) {
              address user = users[i];
              uint256 tokenRequested = tokensRequestedList[i];
              uint256 _bonusRequested = _bonusRequestedList[i];
              uint256 _refereeCount = refereeCountList[i];
  
              totalTokensRequested += tokenRequested;
              tokensRequested[user] = tokenRequested;
              isBonusRequested[user] = true;
              bonusRequested[user] = _bonusRequested;
              refereeCount[user] = _refereeCount;
              if (!allBuyerList.contains(user)) {
                  allBuyerList.add(user);
              }
          }
  
          fundsRaised = fundsAmount;
      }
  }