// SPDX-License-Identifier: MIT

pragma solidity ^0.8.17;

/// @notice Modern, minimalist, and gas efficient ERC-721 implementation.
/// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/tokens/ERC721.sol)
abstract contract ERC721 {
    /*//////////////////////////////////////////////////////////////
                                 EVENTS
    //////////////////////////////////////////////////////////////*/

    event Transfer(address indexed from, address indexed to, uint256 indexed id);

    event Approval(address indexed owner, address indexed spender, uint256 indexed id);

    event ApprovalForAll(address indexed owner, address indexed operator, bool approved);

    /*//////////////////////////////////////////////////////////////
                         METADATA STORAGE/LOGIC
    //////////////////////////////////////////////////////////////*/

    string public name;

    string public symbol;

    function tokenURI(uint256 id) public view virtual returns (string memory);

    /*//////////////////////////////////////////////////////////////
                      ERC721 BALANCE/OWNER STORAGE
    //////////////////////////////////////////////////////////////*/

    mapping(uint256 => address) internal _ownerOf;

    mapping(address => uint256) internal _balanceOf;

    function ownerOf(uint256 id) public view virtual returns (address owner) {
        require((owner = _ownerOf[id]) != address(0), "NOT_MINTED");
    }

    function balanceOf(address owner) public view virtual returns (uint256) {
        require(owner != address(0), "ZERO_ADDRESS");

        return _balanceOf[owner];
    }

    /*//////////////////////////////////////////////////////////////
                         ERC721 APPROVAL STORAGE
    //////////////////////////////////////////////////////////////*/

    mapping(uint256 => address) public getApproved;

    mapping(address => mapping(address => bool)) public isApprovedForAll;

    /*//////////////////////////////////////////////////////////////
                               CONSTRUCTOR
    //////////////////////////////////////////////////////////////*/

    constructor(string memory _name, string memory _symbol) {
        name = _name;
        symbol = _symbol;
    }

    /*//////////////////////////////////////////////////////////////
                              ERC721 LOGIC
    //////////////////////////////////////////////////////////////*/

    function approve(address spender, uint256 id) public virtual {
        address owner = _ownerOf[id];

        require(msg.sender == owner || isApprovedForAll[owner][msg.sender], "NOT_AUTHORIZED");

        getApproved[id] = spender;

        emit Approval(owner, spender, id);
    }

    function setApprovalForAll(address operator, bool approved) public virtual {
        isApprovedForAll[msg.sender][operator] = approved;

        emit ApprovalForAll(msg.sender, operator, approved);
    }

    function transferFrom(
        address from,
        address to,
        uint256 id
    ) public virtual {
        require(from == _ownerOf[id], "WRONG_FROM");

        require(to != address(0), "INVALID_RECIPIENT");

        require(
            msg.sender == from || isApprovedForAll[from][msg.sender] || msg.sender == getApproved[id],
            "NOT_AUTHORIZED"
        );

        // Underflow of the sender's balance is impossible because we check for
        // ownership above and the recipient's balance can't realistically overflow.
        unchecked {
            _balanceOf[from]--;

            _balanceOf[to]++;
        }

        _ownerOf[id] = to;

        delete getApproved[id];

        emit Transfer(from, to, id);
    }

    function safeTransferFrom(
        address from,
        address to,
        uint256 id
    ) public virtual {
        transferFrom(from, to, id);

        require(
            to.code.length == 0 ||
                ERC721TokenReceiver(to).onERC721Received(msg.sender, from, id, "") ==
                ERC721TokenReceiver.onERC721Received.selector,
            "UNSAFE_RECIPIENT"
        );
    }

    function safeTransferFrom(
        address from,
        address to,
        uint256 id,
        bytes calldata data
    ) public virtual {
        transferFrom(from, to, id);

        require(
            to.code.length == 0 ||
                ERC721TokenReceiver(to).onERC721Received(msg.sender, from, id, data) ==
                ERC721TokenReceiver.onERC721Received.selector,
            "UNSAFE_RECIPIENT"
        );
    }

    /*//////////////////////////////////////////////////////////////
                              ERC165 LOGIC
    //////////////////////////////////////////////////////////////*/

    function supportsInterface(bytes4 interfaceId) public view virtual returns (bool) {
        return
            interfaceId == 0x01ffc9a7 || // ERC165 Interface ID for ERC165
            interfaceId == 0x80ac58cd || // ERC165 Interface ID for ERC721
            interfaceId == 0x5b5e139f; // ERC165 Interface ID for ERC721Metadata
    }

    /*//////////////////////////////////////////////////////////////
                        INTERNAL MINT/BURN LOGIC
    //////////////////////////////////////////////////////////////*/

    function _mint(address to, uint256 id) internal virtual {
        require(to != address(0), "INVALID_RECIPIENT");

        require(_ownerOf[id] == address(0), "ALREADY_MINTED");

        // Counter overflow is incredibly unrealistic.
        unchecked {
            _balanceOf[to]++;
        }

        _ownerOf[id] = to;

        emit Transfer(address(0), to, id);
    }

    function _burn(uint256 id) internal virtual {
        address owner = _ownerOf[id];

        require(owner != address(0), "NOT_MINTED");

        // Ownership check above ensures no underflow.
        unchecked {
            _balanceOf[owner]--;
        }

        delete _ownerOf[id];

        delete getApproved[id];

        emit Transfer(owner, address(0), id);
    }

    /*//////////////////////////////////////////////////////////////
                        INTERNAL SAFE MINT LOGIC
    //////////////////////////////////////////////////////////////*/

    function _safeMint(address to, uint256 id) internal virtual {
        _mint(to, id);

        require(
            to.code.length == 0 ||
                ERC721TokenReceiver(to).onERC721Received(msg.sender, address(0), id, "") ==
                ERC721TokenReceiver.onERC721Received.selector,
            "UNSAFE_RECIPIENT"
        );
    }

    function _safeMint(
        address to,
        uint256 id,
        bytes memory data
    ) internal virtual {
        _mint(to, id);

        require(
            to.code.length == 0 ||
                ERC721TokenReceiver(to).onERC721Received(msg.sender, address(0), id, data) ==
                ERC721TokenReceiver.onERC721Received.selector,
            "UNSAFE_RECIPIENT"
        );
    }
}

/// @notice A generic interface for a contract which properly accepts ERC721 tokens.
/// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/tokens/ERC721.sol)
abstract contract ERC721TokenReceiver {
    function onERC721Received(
        address,
        address,
        uint256,
        bytes calldata
    ) external virtual returns (bytes4) {
        return ERC721TokenReceiver.onERC721Received.selector;
    }
}

// OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)

// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)

/**
 * @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;
    }
}

/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
abstract contract Ownable is Context {
    address private _owner;

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

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

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        _checkOwner();
        _;
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if the sender is not the owner.
     */
    function _checkOwner() internal view virtual {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        _transferOwnership(address(0));
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        _transferOwnership(newOwner);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Internal function without access restriction.
     */
    function _transferOwnership(address newOwner) internal virtual {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}

// Interface for Molecule Protocol Smart Contract
interface IMoleculeController {
    // Human readable name of the controller
    // string public _controllerName;
    // // selected logic combinations
    // uint32[] private _selected;

    // Gated: gated by logic
    // Blocked: always return `false`
    // Bypassed: always return `true`
    enum Status {
        Gated,
        Blocked,
        Bypassed
    }

    // // list id => atomic logic contract address
    // mapping(uint32 => address) private _logicContract;
    // // list id => allow- (true) or block- (false) list
    // mapping(uint32 => bool) private _isAllowList;
    // // list id => list name
    // mapping(uint32 => string) private _name;
    // // list id => logic modifier: add negation if true or false for as-is
    // mapping(uint32 => bool) private _reverseLogic; // NOT used, always false

    // event emitted when the controller name is changed
    event ControllerNameUpdated(string name);
    // event emitted when a new list is added
    event LogicAdded(
        uint32 indexed id,
        address indexed logicContract,
        bool isAllowList,
        string name,
        bool reverseLogic
    );
    // event emitted when a list is removed
    event LogicRemoved(uint32 indexed id);
    // event emitted when a new logic combination is selected
    event Selected(uint32[] ids);
    // event emitted when status changed
    event StatusChanged(Status status);

    // Use default logic combination
    function check(address toCheck) external view returns (bool);

    // Use custom logic combination, passed in as an array of list ids
    function check(
        uint32[] memory ids,
        address toCheck
    ) external view returns (bool);

    // Get the current selected logic combination
    function selected() external view returns (uint32[] memory);

    // Get the current status of the contract
    function status() external view returns (Status);

    // Owner only functions
    // Control the status of the contract
    function setStatus(Status status) external;

    // Preselect logic combinations
    function select(uint32[] memory ids) external;

    // Add a new logic
    function addLogic(
        uint32 id,
        address logicContract,
        string memory name,
        bool reverseLogic
    ) external;

    // Remove a logic
    function removeLogic(uint32 id) external;

    // Add new logics in batch
    function addLogicBatch(
        uint32[] memory ids,
        address[] memory logicContracts,
        string[] memory names,
        bool[] memory reverseLogics
    ) external;

    // Remove logics in batch
    function removeLogicBatch(uint32[] memory ids) external;
}

contract ERC721m is ERC721, Ownable {
    enum MoleculeType {
        Approve,
        Burn,
        Mint,
        Transfer
    }

    // Custom error definitions
    error AccountNotAllowedToMint(address to);
    error AccountNotAllowedToBurn(address burner);
    error SenderNotAllowedToTransfer(address sender);
    error OwnerNotAllowedToApprove(address owner);
    error SpenderNotAllowedToReceive(address spender);

    // Molecule addresses
    address public _moleculeApprove;
    address public _moleculeBurn;
    address public _moleculeMint;
    address public _moleculeTransfer;

    event MoleculeUpdated(address molecule, MoleculeType mtype);

    constructor(
        string memory _name,
        string memory _symbol
    ) ERC721(_name, _symbol) {}

    function mint(address to, uint256 tokenId) external {
        if (_moleculeMint != address(0)) {
            if (!IMoleculeController(_moleculeMint).check(to)) {
                revert AccountNotAllowedToMint(to);
            }
        }
        _safeMint(to, tokenId);
    }

    function burn(uint256 tokenId) external {
        address tokenOwner = ownerOf(tokenId);
        if (_moleculeBurn != address(0)) {
            if (!IMoleculeController(_moleculeBurn).check(tokenOwner)) {
                revert AccountNotAllowedToBurn(tokenOwner);
            }
        }
        _burn(tokenId);
    }

    // Transfer function: not internal in solmate contract
    function transferFrom(
        address from,
        address to,
        uint256 tokenId
    ) public virtual override {
        if (_moleculeTransfer != address(0)) {
            if (!IMoleculeController(_moleculeTransfer).check(from)) {
                revert SenderNotAllowedToTransfer(from);
            }
            if (!IMoleculeController(_moleculeTransfer).check(to)) {
                revert SpenderNotAllowedToReceive(to);
            }
        }
        super.transferFrom(from, to, tokenId);
    }

    // @internal functions: applying gating at the internal function level, will apply to both transferFrom and safeTransferFrom
    // Approve function
    function approve(address to, uint256 tokenId) public virtual override {
        if (_moleculeApprove != address(0)) {
            address tokenOwner = ownerOf(tokenId);
            if (!IMoleculeController(_moleculeApprove).check(tokenOwner)) {
                revert OwnerNotAllowedToApprove(tokenOwner);
            }
            if (!IMoleculeController(_moleculeApprove).check(to)) {
                revert SpenderNotAllowedToReceive(to);
            }
        }
        super.approve(to, tokenId);
    }

    // Owner only functions
    // Molecule ERC721 token
    function updateMolecule(
        address molecule,
        MoleculeType mtype
    ) external onlyOwner {
        // allows 0x0 address to be set to remove molecule access control
        if (mtype == MoleculeType.Approve) {
            _moleculeApprove = molecule;
        } else if (mtype == MoleculeType.Burn) {
            _moleculeBurn = molecule;
        } else if (mtype == MoleculeType.Mint) {
            _moleculeMint = molecule;
        } else if (mtype == MoleculeType.Transfer) {
            _moleculeTransfer = molecule;
        }
        emit MoleculeUpdated(molecule, mtype);
    }

    function tokenURI(
        uint256 id
    ) public view virtual override returns (string memory) {}
}