// SPDX-License-Identifier: MIT
pragma solidity 0.8.19;

/// @notice Simple ERC20 + EIP-2612 implementation.
/// @author Solady (https://github.com/vectorized/solady/blob/main/src/tokens/ERC20.sol)
/// @author Modified from Solmate (https://github.com/transmissions11/solmate/blob/main/src/tokens/ERC20.sol)
/// @author Modified from OpenZeppelin (https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/token/ERC20/ERC20.sol)
///
/// @dev Note:
/// The ERC20 standard allows minting and transferring to and from the zero address,
/// minting and transferring zero tokens, as well as self-approvals.
/// For performance, this implementation WILL NOT revert for such actions.
/// Please add any checks with overrides if desired.
abstract contract ERC20 {
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                       CUSTOM ERRORS                        */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev The total supply has overflowed.
    error TotalSupplyOverflow();

    /// @dev The allowance has overflowed.
    error AllowanceOverflow();

    /// @dev The allowance has underflowed.
    error AllowanceUnderflow();

    /// @dev Insufficient balance.
    error InsufficientBalance();

    /// @dev Insufficient allowance.
    error InsufficientAllowance();

    /// @dev The permit is invalid.
    error InvalidPermit();

    /// @dev The permit has expired.
    error PermitExpired();

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                           EVENTS                           */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Emitted when `amount` tokens is transferred from `from` to `to`.
    event Transfer(address indexed from, address indexed to, uint256 amount);

    /// @dev Emitted when `amount` tokens is approved by `owner` to be used by `spender`.
    event Approval(address indexed owner, address indexed spender, uint256 amount);

    /// @dev `keccak256(bytes("Transfer(address,address,uint256)"))`.
    uint256 private constant _TRANSFER_EVENT_SIGNATURE =
        0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef;

    /// @dev `keccak256(bytes("Approval(address,address,uint256)"))`.
    uint256 private constant _APPROVAL_EVENT_SIGNATURE =
        0x8c5be1e5ebec7d5bd14f71427d1e84f3dd0314c0f7b2291e5b200ac8c7c3b925;

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                          STORAGE                           */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev The storage slot for the total supply.
    uint256 private constant _TOTAL_SUPPLY_SLOT = 0x05345cdf77eb68f44c;

    /// @dev The balance slot of `owner` is given by:
    /// ```
    ///     mstore(0x0c, _BALANCE_SLOT_SEED)
    ///     mstore(0x00, owner)
    ///     let balanceSlot := keccak256(0x0c, 0x20)
    /// ```
    uint256 private constant _BALANCE_SLOT_SEED = 0x87a211a2;

    /// @dev The allowance slot of (`owner`, `spender`) is given by:
    /// ```
    ///     mstore(0x20, spender)
    ///     mstore(0x0c, _ALLOWANCE_SLOT_SEED)
    ///     mstore(0x00, owner)
    ///     let allowanceSlot := keccak256(0x0c, 0x34)
    /// ```
    uint256 private constant _ALLOWANCE_SLOT_SEED = 0x7f5e9f20;

    /// @dev The nonce slot of `owner` is given by:
    /// ```
    ///     mstore(0x0c, _NONCES_SLOT_SEED)
    ///     mstore(0x00, owner)
    ///     let nonceSlot := keccak256(0x0c, 0x20)
    /// ```
    uint256 private constant _NONCES_SLOT_SEED = 0x38377508;

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                       ERC20 METADATA                       */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Returns the name of the token.
    function name() public view virtual returns (string memory);

    /// @dev Returns the symbol of the token.
    function symbol() public view virtual returns (string memory);

    /// @dev Returns the decimals places of the token.
    function decimals() public view virtual returns (uint8) {
        return 18;
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                           ERC20                            */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Returns the amount of tokens in existence.
    function totalSupply() public view virtual returns (uint256 result) {
        /// @solidity memory-safe-assembly
        assembly {
            result := sload(_TOTAL_SUPPLY_SLOT)
        }
    }

    /// @dev Returns the amount of tokens owned by `owner`.
    function balanceOf(address owner) public view virtual returns (uint256 result) {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x0c, _BALANCE_SLOT_SEED)
            mstore(0x00, owner)
            result := sload(keccak256(0x0c, 0x20))
        }
    }

    /// @dev Returns the amount of tokens that `spender` can spend on behalf of `owner`.
    function allowance(address owner, address spender)
        public
        view
        virtual
        returns (uint256 result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x20, spender)
            mstore(0x0c, _ALLOWANCE_SLOT_SEED)
            mstore(0x00, owner)
            result := sload(keccak256(0x0c, 0x34))
        }
    }

    /// @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
    ///
    /// Emits a {Approval} event.
    function approve(address spender, uint256 amount) public virtual returns (bool) {
        /// @solidity memory-safe-assembly
        assembly {
            // Compute the allowance slot and store the amount.
            mstore(0x20, spender)
            mstore(0x0c, _ALLOWANCE_SLOT_SEED)
            mstore(0x00, caller())
            sstore(keccak256(0x0c, 0x34), amount)
            // Emit the {Approval} event.
            mstore(0x00, amount)
            log3(0x00, 0x20, _APPROVAL_EVENT_SIGNATURE, caller(), shr(96, mload(0x2c)))
        }
        return true;
    }

    /// @dev Atomically increases the allowance granted to `spender` by the caller.
    ///
    /// Emits a {Approval} event.
    function increaseAllowance(address spender, uint256 difference) public virtual returns (bool) {
        /// @solidity memory-safe-assembly
        assembly {
            // Compute the allowance slot and load its value.
            mstore(0x20, spender)
            mstore(0x0c, _ALLOWANCE_SLOT_SEED)
            mstore(0x00, caller())
            let allowanceSlot := keccak256(0x0c, 0x34)
            let allowanceBefore := sload(allowanceSlot)
            // Add to the allowance.
            let allowanceAfter := add(allowanceBefore, difference)
            // Revert upon overflow.
            if lt(allowanceAfter, allowanceBefore) {
                mstore(0x00, 0xf9067066) // `AllowanceOverflow()`.
                revert(0x1c, 0x04)
            }
            // Store the updated allowance.
            sstore(allowanceSlot, allowanceAfter)
            // Emit the {Approval} event.
            mstore(0x00, allowanceAfter)
            log3(0x00, 0x20, _APPROVAL_EVENT_SIGNATURE, caller(), shr(96, mload(0x2c)))
        }
        return true;
    }

    /// @dev Atomically decreases the allowance granted to `spender` by the caller.
    ///
    /// Emits a {Approval} event.
    function decreaseAllowance(address spender, uint256 difference) public virtual returns (bool) {
        /// @solidity memory-safe-assembly
        assembly {
            // Compute the allowance slot and load its value.
            mstore(0x20, spender)
            mstore(0x0c, _ALLOWANCE_SLOT_SEED)
            mstore(0x00, caller())
            let allowanceSlot := keccak256(0x0c, 0x34)
            let allowanceBefore := sload(allowanceSlot)
            // Revert if will underflow.
            if lt(allowanceBefore, difference) {
                mstore(0x00, 0x8301ab38) // `AllowanceUnderflow()`.
                revert(0x1c, 0x04)
            }
            // Subtract and store the updated allowance.
            let allowanceAfter := sub(allowanceBefore, difference)
            sstore(allowanceSlot, allowanceAfter)
            // Emit the {Approval} event.
            mstore(0x00, allowanceAfter)
            log3(0x00, 0x20, _APPROVAL_EVENT_SIGNATURE, caller(), shr(96, mload(0x2c)))
        }
        return true;
    }

    /// @dev Transfer `amount` tokens from the caller to `to`.
    ///
    /// Requirements:
    /// - `from` must at least have `amount`.
    ///
    /// Emits a {Transfer} event.
    function transfer(address to, uint256 amount) public virtual returns (bool) {
        _beforeTokenTransfer(msg.sender, to, amount);
        /// @solidity memory-safe-assembly
        assembly {
            // Compute the balance slot and load its value.
            mstore(0x0c, _BALANCE_SLOT_SEED)
            mstore(0x00, caller())
            let fromBalanceSlot := keccak256(0x0c, 0x20)
            let fromBalance := sload(fromBalanceSlot)
            // Revert if insufficient balance.
            if gt(amount, fromBalance) {
                mstore(0x00, 0xf4d678b8) // `InsufficientBalance()`.
                revert(0x1c, 0x04)
            }
            // Subtract and store the updated balance.
            sstore(fromBalanceSlot, sub(fromBalance, amount))
            // Compute the balance slot of `to`.
            mstore(0x00, to)
            let toBalanceSlot := keccak256(0x0c, 0x20)
            // Add and store the updated balance of `to`.
            // Will not overflow because the sum of all user balances
            // cannot exceed the maximum uint256 value.
            sstore(toBalanceSlot, add(sload(toBalanceSlot), amount))
            // Emit the {Transfer} event.
            mstore(0x20, amount)
            log3(0x20, 0x20, _TRANSFER_EVENT_SIGNATURE, caller(), shr(96, mload(0x0c)))
        }
        _afterTokenTransfer(msg.sender, to, amount);
        return true;
    }

    /// @dev Transfers `amount` tokens from `from` to `to`.
    ///
    /// Note: Does not update the allowance if it is the maximum uint256 value.
    ///
    /// Requirements:
    /// - `from` must at least have `amount`.
    /// - The caller must have at least `amount` of allowance to transfer the tokens of `from`.
    ///
    /// Emits a {Transfer} event.
    function transferFrom(address from, address to, uint256 amount) public virtual returns (bool) {
        _beforeTokenTransfer(from, to, amount);
        /// @solidity memory-safe-assembly
        assembly {
            let from_ := shl(96, from)
            // Compute the allowance slot and load its value.
            mstore(0x20, caller())
            mstore(0x0c, or(from_, _ALLOWANCE_SLOT_SEED))
            let allowanceSlot := keccak256(0x0c, 0x34)
            let allowance_ := sload(allowanceSlot)
            // If the allowance is not the maximum uint256 value.
            if iszero(eq(allowance_, not(0))) {
                // Revert if the amount to be transferred exceeds the allowance.
                if gt(amount, allowance_) {
                    mstore(0x00, 0x13be252b) // `InsufficientAllowance()`.
                    revert(0x1c, 0x04)
                }
                // Subtract and store the updated allowance.
                sstore(allowanceSlot, sub(allowance_, amount))
            }
            // Compute the balance slot and load its value.
            mstore(0x0c, or(from_, _BALANCE_SLOT_SEED))
            let fromBalanceSlot := keccak256(0x0c, 0x20)
            let fromBalance := sload(fromBalanceSlot)
            // Revert if insufficient balance.
            if gt(amount, fromBalance) {
                mstore(0x00, 0xf4d678b8) // `InsufficientBalance()`.
                revert(0x1c, 0x04)
            }
            // Subtract and store the updated balance.
            sstore(fromBalanceSlot, sub(fromBalance, amount))
            // Compute the balance slot of `to`.
            mstore(0x00, to)
            let toBalanceSlot := keccak256(0x0c, 0x20)
            // Add and store the updated balance of `to`.
            // Will not overflow because the sum of all user balances
            // cannot exceed the maximum uint256 value.
            sstore(toBalanceSlot, add(sload(toBalanceSlot), amount))
            // Emit the {Transfer} event.
            mstore(0x20, amount)
            log3(0x20, 0x20, _TRANSFER_EVENT_SIGNATURE, shr(96, from_), shr(96, mload(0x0c)))
        }
        _afterTokenTransfer(from, to, amount);
        return true;
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                          EIP-2612                          */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Returns the current nonce for `owner`.
    /// This value is used to compute the signature for EIP-2612 permit.
    function nonces(address owner) public view virtual returns (uint256 result) {
        /// @solidity memory-safe-assembly
        assembly {
            // Compute the nonce slot and load its value.
            mstore(0x0c, _NONCES_SLOT_SEED)
            mstore(0x00, owner)
            result := sload(keccak256(0x0c, 0x20))
        }
    }

    /// @dev Sets `value` as the allowance of `spender` over the tokens of `owner`,
    /// authorized by a signed approval by `owner`.
    ///
    /// Emits a {Approval} event.
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) public virtual {
        bytes32 domainSeparator = DOMAIN_SEPARATOR();
        /// @solidity memory-safe-assembly
        assembly {
            // Grab the free memory pointer.
            let m := mload(0x40)
            // Revert if the block timestamp greater than `deadline`.
            if gt(timestamp(), deadline) {
                mstore(0x00, 0x1a15a3cc) // `PermitExpired()`.
                revert(0x1c, 0x04)
            }
            // Clean the upper 96 bits.
            owner := shr(96, shl(96, owner))
            spender := shr(96, shl(96, spender))
            // Compute the nonce slot and load its value.
            mstore(0x0c, _NONCES_SLOT_SEED)
            mstore(0x00, owner)
            let nonceSlot := keccak256(0x0c, 0x20)
            let nonceValue := sload(nonceSlot)
            // Increment and store the updated nonce.
            sstore(nonceSlot, add(nonceValue, 1))
            // Prepare the inner hash.
            // `keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)")`.
            // forgefmt: disable-next-item
            mstore(m, 0x6e71edae12b1b97f4d1f60370fef10105fa2faae0126114a169c64845d6126c9)
            mstore(add(m, 0x20), owner)
            mstore(add(m, 0x40), spender)
            mstore(add(m, 0x60), value)
            mstore(add(m, 0x80), nonceValue)
            mstore(add(m, 0xa0), deadline)
            // Prepare the outer hash.
            mstore(0, 0x1901)
            mstore(0x20, domainSeparator)
            mstore(0x40, keccak256(m, 0xc0))
            // Prepare the ecrecover calldata.
            mstore(0, keccak256(0x1e, 0x42))
            mstore(0x20, and(0xff, v))
            mstore(0x40, r)
            mstore(0x60, s)
            pop(staticcall(gas(), 1, 0, 0x80, 0x20, 0x20))
            // If the ecrecover fails, the returndatasize will be 0x00,
            // `owner` will be be checked if it equals the hash at 0x00,
            // which evaluates to false (i.e. 0), and we will revert.
            // If the ecrecover succeeds, the returndatasize will be 0x20,
            // `owner` will be compared against the returned address at 0x20.
            if iszero(eq(mload(returndatasize()), owner)) {
                mstore(0x00, 0xddafbaef) // `InvalidPermit()`.
                revert(0x1c, 0x04)
            }
            // Compute the allowance slot and store the value.
            // The `owner` is already at slot 0x20.
            mstore(0x40, or(shl(160, _ALLOWANCE_SLOT_SEED), spender))
            sstore(keccak256(0x2c, 0x34), value)
            // Emit the {Approval} event.
            log3(add(m, 0x60), 0x20, _APPROVAL_EVENT_SIGNATURE, owner, spender)
            mstore(0x40, m) // Restore the free memory pointer.
            mstore(0x60, 0) // Restore the zero pointer.
        }
    }

    /// @dev Returns the EIP-2612 domains separator.
    function DOMAIN_SEPARATOR() public view virtual returns (bytes32 result) {
        /// @solidity memory-safe-assembly
        assembly {
            result := mload(0x40) // Grab the free memory pointer.
        }
        //  We simply calculate it on-the-fly to allow for cases where the `name` may change.
        bytes32 nameHash = keccak256(bytes(name()));
        /// @solidity memory-safe-assembly
        assembly {
            let m := result
            // `keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)")`.
            // forgefmt: disable-next-item
            mstore(m, 0x8b73c3c69bb8fe3d512ecc4cf759cc79239f7b179b0ffacaa9a75d522b39400f)
            mstore(add(m, 0x20), nameHash)
            // `keccak256("1")`.
            // forgefmt: disable-next-item
            mstore(add(m, 0x40), 0xc89efdaa54c0f20c7adf612882df0950f5a951637e0307cdcb4c672f298b8bc6)
            mstore(add(m, 0x60), chainid())
            mstore(add(m, 0x80), address())
            result := keccak256(m, 0xa0)
        }
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                  INTERNAL MINT FUNCTIONS                   */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Mints `amount` tokens to `to`, increasing the total supply.
    ///
    /// Emits a {Transfer} event.
    function _mint(address to, uint256 amount) internal virtual {
        _beforeTokenTransfer(address(0), to, amount);
        /// @solidity memory-safe-assembly
        assembly {
            let totalSupplyBefore := sload(_TOTAL_SUPPLY_SLOT)
            let totalSupplyAfter := add(totalSupplyBefore, amount)
            // Revert if the total supply overflows.
            if lt(totalSupplyAfter, totalSupplyBefore) {
                mstore(0x00, 0xe5cfe957) // `TotalSupplyOverflow()`.
                revert(0x1c, 0x04)
            }
            // Store the updated total supply.
            sstore(_TOTAL_SUPPLY_SLOT, totalSupplyAfter)
            // Compute the balance slot and load its value.
            mstore(0x0c, _BALANCE_SLOT_SEED)
            mstore(0x00, to)
            let toBalanceSlot := keccak256(0x0c, 0x20)
            // Add and store the updated balance.
            sstore(toBalanceSlot, add(sload(toBalanceSlot), amount))
            // Emit the {Transfer} event.
            mstore(0x20, amount)
            log3(0x20, 0x20, _TRANSFER_EVENT_SIGNATURE, 0, shr(96, mload(0x0c)))
        }
        _afterTokenTransfer(address(0), to, amount);
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                  INTERNAL BURN FUNCTIONS                   */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Burns `amount` tokens from `from`, reducing the total supply.
    ///
    /// Emits a {Transfer} event.
    function _burn(address from, uint256 amount) internal virtual {
        _beforeTokenTransfer(from, address(0), amount);
        /// @solidity memory-safe-assembly
        assembly {
            // Compute the balance slot and load its value.
            mstore(0x0c, _BALANCE_SLOT_SEED)
            mstore(0x00, from)
            let fromBalanceSlot := keccak256(0x0c, 0x20)
            let fromBalance := sload(fromBalanceSlot)
            // Revert if insufficient balance.
            if gt(amount, fromBalance) {
                mstore(0x00, 0xf4d678b8) // `InsufficientBalance()`.
                revert(0x1c, 0x04)
            }
            // Subtract and store the updated balance.
            sstore(fromBalanceSlot, sub(fromBalance, amount))
            // Subtract and store the updated total supply.
            sstore(_TOTAL_SUPPLY_SLOT, sub(sload(_TOTAL_SUPPLY_SLOT), amount))
            // Emit the {Transfer} event.
            mstore(0x00, amount)
            log3(0x00, 0x20, _TRANSFER_EVENT_SIGNATURE, shr(96, shl(96, from)), 0)
        }
        _afterTokenTransfer(from, address(0), amount);
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                INTERNAL TRANSFER FUNCTIONS                 */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Moves `amount` of tokens from `from` to `to`.
    function _transfer(address from, address to, uint256 amount) internal virtual {
        _beforeTokenTransfer(from, to, amount);
        /// @solidity memory-safe-assembly
        assembly {
            let from_ := shl(96, from)
            // Compute the balance slot and load its value.
            mstore(0x0c, or(from_, _BALANCE_SLOT_SEED))
            let fromBalanceSlot := keccak256(0x0c, 0x20)
            let fromBalance := sload(fromBalanceSlot)
            // Revert if insufficient balance.
            if gt(amount, fromBalance) {
                mstore(0x00, 0xf4d678b8) // `InsufficientBalance()`.
                revert(0x1c, 0x04)
            }
            // Subtract and store the updated balance.
            sstore(fromBalanceSlot, sub(fromBalance, amount))
            // Compute the balance slot of `to`.
            mstore(0x00, to)
            let toBalanceSlot := keccak256(0x0c, 0x20)
            // Add and store the updated balance of `to`.
            // Will not overflow because the sum of all user balances
            // cannot exceed the maximum uint256 value.
            sstore(toBalanceSlot, add(sload(toBalanceSlot), amount))
            // Emit the {Transfer} event.
            mstore(0x20, amount)
            log3(0x20, 0x20, _TRANSFER_EVENT_SIGNATURE, shr(96, from_), shr(96, mload(0x0c)))
        }
        _afterTokenTransfer(from, to, amount);
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                INTERNAL ALLOWANCE FUNCTIONS                */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Updates the allowance of `owner` for `spender` based on spent `amount`.
    function _spendAllowance(address owner, address spender, uint256 amount) internal virtual {
        /// @solidity memory-safe-assembly
        assembly {
            // Compute the allowance slot and load its value.
            mstore(0x20, spender)
            mstore(0x0c, _ALLOWANCE_SLOT_SEED)
            mstore(0x00, owner)
            let allowanceSlot := keccak256(0x0c, 0x34)
            let allowance_ := sload(allowanceSlot)
            // If the allowance is not the maximum uint256 value.
            if iszero(eq(allowance_, not(0))) {
                // Revert if the amount to be transferred exceeds the allowance.
                if gt(amount, allowance_) {
                    mstore(0x00, 0x13be252b) // `InsufficientAllowance()`.
                    revert(0x1c, 0x04)
                }
                // Subtract and store the updated allowance.
                sstore(allowanceSlot, sub(allowance_, amount))
            }
        }
    }

    /// @dev Sets `amount` as the allowance of `spender` over the tokens of `owner`.
    ///
    /// Emits a {Approval} event.
    function _approve(address owner, address spender, uint256 amount) internal virtual {
        /// @solidity memory-safe-assembly
        assembly {
            let owner_ := shl(96, owner)
            // Compute the allowance slot and store the amount.
            mstore(0x20, spender)
            mstore(0x0c, or(owner_, _ALLOWANCE_SLOT_SEED))
            sstore(keccak256(0x0c, 0x34), amount)
            // Emit the {Approval} event.
            mstore(0x00, amount)
            log3(0x00, 0x20, _APPROVAL_EVENT_SIGNATURE, shr(96, owner_), shr(96, mload(0x2c)))
        }
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                     HOOKS TO OVERRIDE                      */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Hook that is called before any transfer of tokens.
    /// This includes minting and burning.
    function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual {}

    /// @dev Hook that is called after any transfer of tokens.
    /// This includes minting and burning.
    function _afterTokenTransfer(address from, address to, uint256 amount) internal virtual {}
}

/// @notice Simple single owner authorization mixin.
/// @author Solady (https://github.com/vectorized/solady/blob/main/src/auth/Ownable.sol)
/// @dev While the ownable portion follows
/// [EIP-173](https://eips.ethereum.org/EIPS/eip-173) for compatibility,
/// the nomenclature for the 2-step ownership handover may be unique to this codebase.
abstract contract Ownable {
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                       CUSTOM ERRORS                        */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev The caller is not authorized to call the function.
    error Unauthorized();

    /// @dev The `newOwner` cannot be the zero address.
    error NewOwnerIsZeroAddress();

    /// @dev The `pendingOwner` does not have a valid handover request.
    error NoHandoverRequest();

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                           EVENTS                           */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev The ownership is transferred from `oldOwner` to `newOwner`.
    /// This event is intentionally kept the same as OpenZeppelin's Ownable to be
    /// compatible with indexers and [EIP-173](https://eips.ethereum.org/EIPS/eip-173),
    /// despite it not being as lightweight as a single argument event.
    event OwnershipTransferred(address indexed oldOwner, address indexed newOwner);

    /// @dev An ownership handover to `pendingOwner` has been requested.
    event OwnershipHandoverRequested(address indexed pendingOwner);

    /// @dev The ownership handover to `pendingOwner` has been canceled.
    event OwnershipHandoverCanceled(address indexed pendingOwner);

    /// @dev `keccak256(bytes("OwnershipTransferred(address,address)"))`.
    uint256 private constant _OWNERSHIP_TRANSFERRED_EVENT_SIGNATURE =
        0x8be0079c531659141344cd1fd0a4f28419497f9722a3daafe3b4186f6b6457e0;

    /// @dev `keccak256(bytes("OwnershipHandoverRequested(address)"))`.
    uint256 private constant _OWNERSHIP_HANDOVER_REQUESTED_EVENT_SIGNATURE =
        0xdbf36a107da19e49527a7176a1babf963b4b0ff8cde35ee35d6cd8f1f9ac7e1d;

    /// @dev `keccak256(bytes("OwnershipHandoverCanceled(address)"))`.
    uint256 private constant _OWNERSHIP_HANDOVER_CANCELED_EVENT_SIGNATURE =
        0xfa7b8eab7da67f412cc9575ed43464468f9bfbae89d1675917346ca6d8fe3c92;

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                          STORAGE                           */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev The owner slot is given by: `not(_OWNER_SLOT_NOT)`.
    /// It is intentionally chosen to be a high value
    /// to avoid collision with lower slots.
    /// The choice of manual storage layout is to enable compatibility
    /// with both regular and upgradeable contracts.
    uint256 private constant _OWNER_SLOT_NOT = 0x8b78c6d8;

    /// The ownership handover slot of `newOwner` is given by:
    /// ```
    ///     mstore(0x00, or(shl(96, user), _HANDOVER_SLOT_SEED))
    ///     let handoverSlot := keccak256(0x00, 0x20)
    /// ```
    /// It stores the expiry timestamp of the two-step ownership handover.
    uint256 private constant _HANDOVER_SLOT_SEED = 0x389a75e1;

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                     INTERNAL FUNCTIONS                     */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Initializes the owner directly without authorization guard.
    /// This function must be called upon initialization,
    /// regardless of whether the contract is upgradeable or not.
    /// This is to enable generalization to both regular and upgradeable contracts,
    /// and to save gas in case the initial owner is not the caller.
    /// For performance reasons, this function will not check if there
    /// is an existing owner.
    function _initializeOwner(address newOwner) internal virtual {
        /// @solidity memory-safe-assembly
        assembly {
            // Clean the upper 96 bits.
            newOwner := shr(96, shl(96, newOwner))
            // Store the new value.
            sstore(not(_OWNER_SLOT_NOT), newOwner)
            // Emit the {OwnershipTransferred} event.
            log3(0, 0, _OWNERSHIP_TRANSFERRED_EVENT_SIGNATURE, 0, newOwner)
        }
    }

    /// @dev Sets the owner directly without authorization guard.
    function _setOwner(address newOwner) internal virtual {
        /// @solidity memory-safe-assembly
        assembly {
            let ownerSlot := not(_OWNER_SLOT_NOT)
            // Clean the upper 96 bits.
            newOwner := shr(96, shl(96, newOwner))
            // Emit the {OwnershipTransferred} event.
            log3(0, 0, _OWNERSHIP_TRANSFERRED_EVENT_SIGNATURE, sload(ownerSlot), newOwner)
            // Store the new value.
            sstore(ownerSlot, newOwner)
        }
    }

    /// @dev Throws if the sender is not the owner.
    function _checkOwner() internal view virtual {
        /// @solidity memory-safe-assembly
        assembly {
            // If the caller is not the stored owner, revert.
            if iszero(eq(caller(), sload(not(_OWNER_SLOT_NOT)))) {
                mstore(0x00, 0x82b42900) // `Unauthorized()`.
                revert(0x1c, 0x04)
            }
        }
    }

    /// @dev Returns how long a two-step ownership handover is valid for in seconds.
    /// Override to return a different value if needed.
    /// Made internal to conserve bytecode. Wrap it in a public function if needed.
    function _ownershipHandoverValidFor() internal view virtual returns (uint64) {
        return 48 * 3600;
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                  PUBLIC UPDATE FUNCTIONS                   */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Allows the owner to transfer the ownership to `newOwner`.
    function transferOwnership(address newOwner) public payable virtual onlyOwner {
        /// @solidity memory-safe-assembly
        assembly {
            if iszero(shl(96, newOwner)) {
                mstore(0x00, 0x7448fbae) // `NewOwnerIsZeroAddress()`.
                revert(0x1c, 0x04)
            }
        }
        _setOwner(newOwner);
    }

    /// @dev Allows the owner to renounce their ownership.
    function renounceOwnership() public payable virtual onlyOwner {
        _setOwner(address(0));
    }

    /// @dev Request a two-step ownership handover to the caller.
    /// The request will automatically expire in 48 hours (172800 seconds) by default.
    function requestOwnershipHandover() public payable virtual {
        unchecked {
            uint256 expires = block.timestamp + _ownershipHandoverValidFor();
            /// @solidity memory-safe-assembly
            assembly {
                // Compute and set the handover slot to `expires`.
                mstore(0x0c, _HANDOVER_SLOT_SEED)
                mstore(0x00, caller())
                sstore(keccak256(0x0c, 0x20), expires)
                // Emit the {OwnershipHandoverRequested} event.
                log2(0, 0, _OWNERSHIP_HANDOVER_REQUESTED_EVENT_SIGNATURE, caller())
            }
        }
    }

    /// @dev Cancels the two-step ownership handover to the caller, if any.
    function cancelOwnershipHandover() public payable virtual {
        /// @solidity memory-safe-assembly
        assembly {
            // Compute and set the handover slot to 0.
            mstore(0x0c, _HANDOVER_SLOT_SEED)
            mstore(0x00, caller())
            sstore(keccak256(0x0c, 0x20), 0)
            // Emit the {OwnershipHandoverCanceled} event.
            log2(0, 0, _OWNERSHIP_HANDOVER_CANCELED_EVENT_SIGNATURE, caller())
        }
    }

    /// @dev Allows the owner to complete the two-step ownership handover to `pendingOwner`.
    /// Reverts if there is no existing ownership handover requested by `pendingOwner`.
    function completeOwnershipHandover(address pendingOwner) public payable virtual onlyOwner {
        /// @solidity memory-safe-assembly
        assembly {
            // Compute and set the handover slot to 0.
            mstore(0x0c, _HANDOVER_SLOT_SEED)
            mstore(0x00, pendingOwner)
            let handoverSlot := keccak256(0x0c, 0x20)
            // If the handover does not exist, or has expired.
            if gt(timestamp(), sload(handoverSlot)) {
                mstore(0x00, 0x6f5e8818) // `NoHandoverRequest()`.
                revert(0x1c, 0x04)
            }
            // Set the handover slot to 0.
            sstore(handoverSlot, 0)
        }
        _setOwner(pendingOwner);
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                   PUBLIC READ FUNCTIONS                    */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Returns the owner of the contract.
    function owner() public view virtual returns (address result) {
        /// @solidity memory-safe-assembly
        assembly {
            result := sload(not(_OWNER_SLOT_NOT))
        }
    }

    /// @dev Returns the expiry timestamp for the two-step ownership handover to `pendingOwner`.
    function ownershipHandoverExpiresAt(address pendingOwner)
        public
        view
        virtual
        returns (uint256 result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            // Compute the handover slot.
            mstore(0x0c, _HANDOVER_SLOT_SEED)
            mstore(0x00, pendingOwner)
            // Load the handover slot.
            result := sload(keccak256(0x0c, 0x20))
        }
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                         MODIFIERS                          */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Marks a function as only callable by the owner.
    modifier onlyOwner() virtual {
        _checkOwner();
        _;
    }
}

// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/IERC20.sol)

/**
 * @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 amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

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

contract BBC is ERC20, Ownable {
    struct User {
        bool isBlacklisted;
        bool isAutomatedMarketMaker;
        bool isExcludedFromFees;
        bool isExcludedFromMaxTransactionAmount;
    }

    struct Fees {
        uint8 buy;
        uint8 sell;
    }

    struct Settings {
        bool limitsInEffect;
        bool blacklistRenounced;
        bool feeChangeRenounced;
        bool tradingActive;
        /// @dev Upon enabling trading, record the end block for bot protection fee
        /// @dev This fee is a 90% fee that is reduced by 5% every block for 18 blocks.
        uint216 endBlock;
    }

    /// @dev Constant to access the allowance slot
    uint256 private constant _ALLOWANCE_SLOT_SEED = 0x7f5e9f20;
    uint256 public constant MAX_SUPPLY = 10_000_000 * 1e18;
    address public constant BURN_ADDRESS = address(0xdead);

    uint256 public maxTransactionAmount;
    uint256 public maxWallet;

    uint256 public tokensForBotProtection;

    Fees public feeAmounts;

    Settings private settings = Settings({
        limitsInEffect: true,
        blacklistRenounced: false,
        feeChangeRenounced: false,
        tradingActive: false,
        endBlock: uint216(0)
    });

    mapping(address => User) private _users;

    event ExcludeFromFees(address indexed account, bool isExcluded);
    event ExcludeFromMaxTransaction(address indexed account, bool isExcluded);
    event FeesUpdated(uint8 buyFee, uint8 sellFee);
    event MaxTransactionAmountUpdated(uint256 newAmount, uint256 oldAmount);
    event MaxWalletAmountUpdated(uint256 newAmount, uint256 oldAmount);
    event SetAutomatedMarketMakerPair(address indexed pair, bool value);

    error BBC__BlacklistModificationDisabled();
    error BBC__BuyAmountGreaterThanMax();
    error BBC__CannotTransferFromAddressZero();
    error BBC__CannotTransferToAddressZero();
    error BBC__ErrorWithdrawingEth();
    error BBC__FeeChangeRenounced();
    error BBC__MaxFeeFivePercent();
    error BBC__MaxTransactionTooLow();
    error BBC__MaxWalletAmountExceeded();
    error BBC__MaxWalletAmountTooLow();
    error BBC__OnlyOwner();
    error BBC__ReceiverBlacklisted();
    error BBC__SellAmountGreaterThanMax();
    error BBC__SenderBlacklisted();
    error BBC__TokenAddressCannotBeAddressZero();
    error BBC__TradingNotActive();

    constructor(address ownerWallet) {
        _initializeOwner(ownerWallet);

        maxTransactionAmount = MAX_SUPPLY / 100; // 1%
        maxWallet = MAX_SUPPLY / 100; // 1%

        feeAmounts = Fees({buy: 0, sell: 5});

        _users[ownerWallet] = User({
            isExcludedFromFees: true,
            isExcludedFromMaxTransactionAmount: true,
            isAutomatedMarketMaker: false,
            isBlacklisted: false
        });
        _users[address(this)] = User({
            isExcludedFromFees: true,
            isExcludedFromMaxTransactionAmount: true,
            isAutomatedMarketMaker: false,
            isBlacklisted: false
        });
        _users[BURN_ADDRESS] = User({
            isExcludedFromFees: true,
            isExcludedFromMaxTransactionAmount: true,
            isAutomatedMarketMaker: false,
            isBlacklisted: false
        });
        _users[address(ownerWallet)] = User({
            isExcludedFromFees: true,
            isExcludedFromMaxTransactionAmount: true,
            isAutomatedMarketMaker: false,
            isBlacklisted: false
        });

        _mint(ownerWallet, MAX_SUPPLY);
    }

    receive() external payable {}

    function name() public pure override returns (string memory) {
        return "Big Bald Cock";
    }

    function symbol() public pure override returns (string memory) {
        return "BBC";
    }

    function enableTrading() public {
        _requireIsOwner();
        settings.endBlock = uint216(block.number) + 19;
        settings.tradingActive = true;
    }

    // remove limits after token is stable
    function removeLimits() external {
        _requireIsOwner();
        settings.limitsInEffect = false;
    }

    function updateMaxTransactionAmount(uint256 newAmount) external {
        _requireIsOwner();
        if (newAmount < MAX_SUPPLY * 5 / 1000) {
            revert BBC__MaxTransactionTooLow();
        }
        uint256 oldMaxTransactionAmount = maxTransactionAmount;
        maxTransactionAmount = newAmount;
        emit MaxTransactionAmountUpdated(newAmount, oldMaxTransactionAmount);
    }

    function updateMaxWalletAmount(uint256 newNum) external {
        _requireIsOwner();
        if (newNum < MAX_SUPPLY / 100) {
            revert BBC__MaxWalletAmountTooLow();
        }
        uint256 oldMaxWallet = maxWallet;
        maxWallet = newNum;
        emit MaxWalletAmountUpdated(newNum, oldMaxWallet);
    }

    function updateBuyFees(uint8 burnFee) external {
        _requireIsOwner();

        if (settings.feeChangeRenounced) {
            revert BBC__FeeChangeRenounced();
        }

        if (burnFee > 5) {
            revert BBC__MaxFeeFivePercent();
        }

        uint8 sellFee = feeAmounts.sell;

        feeAmounts =
            Fees({buy: burnFee, sell: sellFee});
        emit FeesUpdated(burnFee, sellFee);
    }

    function updateSellFees(uint8 burnFee) external {
        _requireIsOwner();

        if (settings.feeChangeRenounced) {
            revert BBC__FeeChangeRenounced();
        }

        if (burnFee > 5) {
            revert BBC__MaxFeeFivePercent();
        }

        uint8 buyFee = feeAmounts.buy;

        feeAmounts =
            Fees({buy: buyFee, sell: burnFee});
        emit FeesUpdated(buyFee, burnFee);
    }

    function excludeFromFees(address account, bool excluded) external {
        _requireIsOwner();
        _users[account].isExcludedFromFees = excluded;
        emit ExcludeFromFees(account, excluded);
    }

    function excludeFromMaxTransaction(address account, bool isExcluded) external {
        _requireIsOwner();
        _users[account].isExcludedFromMaxTransactionAmount = isExcluded;
        emit ExcludeFromMaxTransaction(account, isExcluded);
    }

    function setAutomatedMarketMakerPair(address pair, bool value) external {
        _requireIsOwner();

        _users[pair].isAutomatedMarketMaker = value;
        emit SetAutomatedMarketMakerPair(pair, value);
    }

    function withdrawStuckBBC(uint256 amount) external {
        _requireIsOwner();
        uint256 transferAmount;
        if (amount == 0) {
            transferAmount = balanceOf(address(this));
        } else {
            transferAmount = amount;
        }
        super._transfer(address(this), msg.sender, transferAmount);
    }

    function withdrawStuckToken(address _token) external {
        _requireIsOwner();
        if (_token == address(0)) {
            revert BBC__TokenAddressCannotBeAddressZero();
        }
        uint256 _contractBalance = IERC20(_token).balanceOf(address(this));
        IERC20(_token).transfer(msg.sender, _contractBalance);
    }

    function withdrawStuckEth() external {
        _requireIsOwner();
        (bool success,) = msg.sender.call{value: address(this).balance}("");
        if (!success) {
            revert BBC__ErrorWithdrawingEth();
        }
    }

    function renounceBlacklist() external {
        _requireIsOwner();
        settings.blacklistRenounced = true;
    }

    function renounceFeeChange() external {
        _requireIsOwner();
        settings.feeChangeRenounced = true;
    }

    function blacklist(address account) external {
        _requireIsOwner();
        if (settings.blacklistRenounced) {
            revert BBC__BlacklistModificationDisabled();
        }
        _users[account].isBlacklisted = true;
    }

    // @dev unblacklist address; not affected by blacklistRenounced
    function unblacklist(address account) external {
        _requireIsOwner();
        _users[account].isBlacklisted = false;
    }

    function isExcludedFromFees(address account) external view returns (bool) {
        return _users[account].isExcludedFromFees;
    }

    function isExcludedFromMaxTransactionAmount(address account) external view returns (bool) {
        return _users[account].isExcludedFromMaxTransactionAmount;
    }

    function isAutomatedMarketMakerPair(address pair) external view returns (bool) {
        return _users[pair].isAutomatedMarketMaker;
    }

    function isBlacklisted(address account) external view returns (bool) {
        return _users[account].isBlacklisted;
    }

    function isBlacklistRenounced() external view returns (bool) {
        return settings.blacklistRenounced;
    }

    function isFeeChangeRenounced() external view returns (bool) {
        return settings.feeChangeRenounced;
    }

    function isTradingActive() external view returns (bool) {
        return settings.tradingActive;
    }

    function isLimitInEffect() external view returns (bool) {
        return settings.limitsInEffect;
    }

    function transfer(address to, uint256 amount) public override returns (bool) {
        _transfer(msg.sender, to, amount);
        return true;
    }

    function transferFrom(address from, address to, uint256 amount) public override returns (bool) {
        // Check allowance and reduce it if used, reverts with `InsufficientAllowance()` if not approved.
        assembly {
            let from_ := shl(96, from)
            // Compute the allowance slot and load its value.
            mstore(0x20, caller())
            mstore(0x0c, or(from_, _ALLOWANCE_SLOT_SEED))
            let allowanceSlot := keccak256(0x0c, 0x34)
            let allowance_ := sload(allowanceSlot)
            // If the allowance is not the maximum uint256 value.
            if iszero(eq(allowance_, not(0))) {
                // Revert if the amount to be transferred exceeds the allowance.
                if gt(amount, allowance_) {
                    mstore(0x00, 0x13be252b) // `InsufficientAllowance()`.
                    revert(0x1c, 0x04)
                }
                // Subtract and store the updated allowance.
                sstore(allowanceSlot, sub(allowance_, amount))
            }
        }
        _transfer(from, to, amount);
        return true;
    }

    function _transfer(address from, address to, uint256 amount) internal override {
        // Ignore mints, burns not enabled
        if (from == address(0)) {
            revert BBC__CannotTransferFromAddressZero();
        }
        if (to == address(0)) {
            revert BBC__CannotTransferToAddressZero();
        }

        User memory fromData = _users[from];
        User memory toData = _users[to];
        Settings memory settingCache = settings;

        if (!settingCache.tradingActive) {
            if (!fromData.isExcludedFromFees) {
                if (!toData.isExcludedFromFees) {
                    revert BBC__TradingNotActive();
                }
            }
        }

        // Apply blacklist protection
        if (fromData.isBlacklisted) {
            revert BBC__SenderBlacklisted();
        }
        if (toData.isBlacklisted) {
            revert BBC__ReceiverBlacklisted();
        }

        // If zero amount, continue
        if (amount == 0) {
            return;
        }

        bool excludedFromFees = fromData.isExcludedFromFees || toData.isExcludedFromFees;

        // Cache transaction type for reference.
        // 1 = Buy
        // 2 = Sell
        // 3 = Transfer
        uint8 txType = 3;

        if (fromData.isAutomatedMarketMaker) {
            // Buys originate from the AMM pair
            txType = 1;
        } else if (toData.isAutomatedMarketMaker) {
            // Sells send funds to AMM pair
            txType = 2;
        }

        if (settingCache.limitsInEffect) {
            //when buy
            if (txType == 1 && !toData.isExcludedFromMaxTransactionAmount) {
                if (amount > maxTransactionAmount) {
                    revert BBC__BuyAmountGreaterThanMax();
                }
                if (amount + balanceOf(to) > maxWallet) {
                    revert BBC__MaxWalletAmountExceeded();
                }
            }
            //when sell
            else if (txType == 2 && !fromData.isExcludedFromMaxTransactionAmount) {
                if (amount > maxTransactionAmount) {
                    revert BBC__SellAmountGreaterThanMax();
                }
            } else if (!toData.isExcludedFromMaxTransactionAmount) {
                if (amount + balanceOf(to) > maxWallet) {
                    revert BBC__MaxWalletAmountExceeded();
                }
            }
        }
        

        if (txType < 3) {
            uint256 fees = 0;
            // only take fees on buys/sells, do not take on wallet transfers
            if (!excludedFromFees) {
                Fees memory feeCache = feeAmounts;
                // on sell
                if (txType == 2) {
                    if (feeCache.sell > 0) {
                        fees = amount * feeCache.sell / 100;
                    }
                }
                // on buy
                else if (txType == 1) {
                    if (feeCache.buy > 0) {
                        fees = amount * feeCache.buy / 100;
                    }
                }

                if (block.number < settingCache.endBlock) {
                    uint256 blocksLeft = settingCache.endBlock - block.number;
                    uint256 botFeeMultiplier = 90;

                    // Apply sniper protection - first 18 blocks have a fee reduced 5% each block.
                    if (blocksLeft < 18) {
                        botFeeMultiplier -= (5 * (18 - blocksLeft));
                    }
                    uint256 botFee = (amount * botFeeMultiplier) / 100;
                    super._transfer(from, owner(), botFee);
                    amount -= botFee;
                    tokensForBotProtection += botFee;
                }

                amount -= fees;

                // We burn all extra fees after bot protection has ended.
                if (fees > 0) {
                    super._transfer(from, BURN_ADDRESS, fees);
                }
            }
        }
        super._transfer(from, to, amount);
    }

    function _requireIsOwner() internal view {
        if (msg.sender != owner()) {
            revert BBC__OnlyOwner();
        }
    }
}

{
  "compilationTarget": {
    "BBC.sol": "BBC"
  },
  "evmVersion": "paris",
  "libraries": {},
  "metadata": {
    "bytecodeHash": "ipfs"
  },
  "optimizer": {
    "enabled": false,
    "runs": 200
  },
  "remappings": []
}