// Contract: MonstersAndVillains
// Target function: function getStateMachine() external view returns(uint256)
 types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize, which returns 0 for contracts in
        // construction, since the code is only stored at the end of the
        // constructor execution.

        uint256 size;
        assembly {
            size := extcodesize(account)
        }
        return size > 0;
    }

    /**
     * @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://diligence.consensys.net/posts/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/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");

        (bool success, ) = recipient.call{value: amount}("");
        require(success, "Addr: cant send val, rcpt revert");
    }

    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain `call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionCall(target, data, "Address: low-level call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Addr: low-level call value fail");
    }

    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(address(this).balance >= value, "Addr: insufficient balance call");
        require(isContract(target), "Address: call to non-contract");

        (bool success, bytes memory returndata) = target.call{value: value}(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Addr: low-level static call fail");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        require(isContract(target), "Addr: static call non-contract");

        (bool success, bytes memory returndata) = target.staticcall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Addr: low-level del call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(isContract(target), "Addr: delegate call non-contract");

        (bool success, bytes memory returndata) = target.delegatecall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    function _verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) private pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            // 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

                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}

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() {
        _setOwner(_msgSender());
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        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 {
        _setOwner(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 0x address");
        _setOwner(newOwner);
    }

    function _setOwner(address newOwner) private {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}

abstract contract Functional {
    function toString(uint256 value) internal pure returns (string memory) {
        if (value == 0) {
            return "0";
        }
        uint256 temp = value;
        uint256 digits;
        while (temp != 0) {
            digits++;
            temp /= 10;
        }
        bytes memory buffer = new bytes(digits);
        while (value != 0) {
            digits -= 1;
            buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));
            value /= 10;
        }
        return string(buffer);
    }
    
    bool private _reentryKey = false;
    modifier reentryLock {
        require(!_reentryKey, "attempt reenter locked function");
        _reentryKey = true;
        _;
        _reentryKey = false;
    }
}

// ******************************************************************************************************************************
// **************************************************  Start of Main Contract ***************************************************
// ******************************************************************************************************************************

contract MonstersAndVillains is IERC721, Ownable, Functional {

    using Address for address;
    
    // Token name
    string private _name;

    // Token symbol
    string private _symbol;
    
    // URI Root Location for Json Files
    string private _baseURI;

    // Mapping from token ID to owner address
    mapping(uint256 => address) private _owners;

    // Mapping owner address to token count
    mapping(address => uint256) private _balances;

    // Mapping from token ID to approved address
    mapping(uint256 => address) private _tokenApprovals;

    // Mapping from owner to operator approvals
    mapping(address => mapping(address => bool)) private _operatorApprovals;
    
    mapping(uint256 => uint256[4]) private _burned_for_villain;
    mapping(uint256 => uint256[8]) private _burned_for_super;

    mapping(address => bool) private _whitelist;
    mapping(address => uint256) public wlmints;

    // Specific Functionality
    bool public mintActive;
    bool public villActive;
    bool public suprActive;
    bool public WLActive;

    uint256 public price;
    uint256 public totalMint;
    uint256 public numberMinted;
    uint256 public numVillains;
    uint256 public numSupers;
    
    uint256 public numberBurned;

    

    /**
     * @dev Initializes the contract by setting a `name` and a `symbol` to the token collection.
     */
    constructor() {
        _name = "Monsters and Villains";
        _symbol = "M&V";
        _baseURI = "https://egonauts.io/monsters/metadata/";
        
        totalMint = 1024;
        price = 100 * (10 ** 15); // 0.1
    }

    //@dev See {IERC165-supportsInterface}. Interfaces Supported by this Standard
    function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
        return  interfaceId == type(IERC721).interfaceId ||
                interfaceId == type(IERC721Metadata).interfaceId ||
                interfaceId == type(IERC165).interfaceId ||
                interfaceId == MonstersAndVillains.onERC721Received.selector;
    }
    
    // Standard Withdraw function for the owner to pull the contract
    function withdraw() external onlyOwner {
        uint256 fundsAvailable = address(this).balance;
        bool success;
        (success, ) = _msgSender().call{value: fundsAvailable}("");
        require(success, "Transaction Unsuccessful");
    }   
    
    function airDropSingle(address _to, uint256 _qty) external onlyOwner {
        require((numberMinted + _qty) > numberMinted, "Math overflow error");
        require((numberMinted + _qty) <= totalMint, "Cannot fill order");
        
        for(uint256 i = 0; i < _qty; i++) {
            _safeMint(_to, numberMinted + 1);
            numberMinted ++;
        }
    }
    
    function airDrop(address[] memory _to, uint256[] memory _qty) external onlyOwner {
        // use with care, qty is not being calculated for a check.
        require( _to.length == _qty.length, "array lengths must match");

        for(uint256 i = 0; i < _qty.length; i++) {
            for(uint256 j = 0; j < _qty[i]; j++) {
                _safeMint( _to[i], numberMinted + 1 );
                numberMinted ++;
            }
        }
    }
    
    function mint(uint256 qty) external payable reentryLock {
        require(mintActive, "Not open to the public");
        require(qty <= 10, "10 at a time or less, please");
        require(qty + numberMinted <= totalMint, "Sold Out");
        require((numberMinted + qty) > numberMinted, "Math overflow error");
        require(msg.value == qty * price, "Wrong amount sent");

        for(uint256 i = 0; i < qty; i++) {
            _safeMint(_msgSender(), numberMinted + 1);
            numberMinted ++;
        }
    }

    function whitelistMint(uint256 qty) external payable reentryLock {
        require(WLActive, "Whitelist not open");
        require(_whitelist[_msgSender()] == true, "Not Whitelisted");
        require( qty + wlmints[_msgSender()] <= 6, "Over max whitelist mints");
        require(qty + numberMinted <= totalMint, "Sold Out");
        require((numberMinted + qty) > numberMinted, "Math overflow error");
        require(msg.value == qty * price, "Wrong amount sent");

        wlmints[_msgSender()] += qty;

        for(uint256 i = 0; i < qty; i++) {
            _safeMint(_msgSender(), numberMinted + 1);
            numberMinted ++;
        }
    }

    function mintVillain(uint256 t1, uint256 t2, uint256 t3, uint256 t4) external reentryLock {
        require(villActive, "Not open to the public");
        // Validate ownership in wallet
        require(ownerOf(t1) == _msgSender(), "you don't own that");
        require(ownerOf(t2) == _msgSender(), "you don't own that");
        require(ownerOf(t3) == _msgSender(), "you don't own that");
        require(ownerOf(t4) == _msgSender(), "you don't own that");
        // Validate token Ids are the right type
        require(t1 < 1025, "Wrong Type");
        require(t2 < 1025, "Wrong Type");
        require(t3 < 1025, "Wrong Type");
        require(t4 < 1025, "Wrong Type");
        // Make the sacrifice
        _burn(t1);
        _burn(t2);
        _burn(t3);
        _burn(t4);
        // grant evolved villain
        numVillains ++;
        uint256 tokenid = numVillains + 1024;
        _safeMint(_msgSender(), tokenid);

        // update the traits that went into building this tokenid
        _burned_for_villain[tokenid] = [t1, t2, t3, t4];
    }
    
    function mintSuperVillain(uint256 v1, uint256 v2) external reentryLock {
        require(suprActive, "Not open to the public");
        // Validate Ownership
        require(ownerOf(v1) == _msgSender(), "you don't own that");
        require(ownerOf(v2) == _msgSender(), "you don't own that");
        // Validate correct type
        require( (v1 > 1024)&&(v1 < 2000), "Wrong Type");
        require( (v2 > 1024)&&(v2 < 2000), "Wrong Type");
        // Make the sacrifice
        _burn(v1);
        _burn(v2);
        // grant evolved superVillain
        numSupers ++;
        uint256 tokenid = numSupers + 2000;
        _safeMint(_msgSender(), tokenid);

        // update the traits that went into building this tokenid
        for (uint256 i; i < 8; i++){
            if (i<4){
                _burned_for_super[tokenid][i] = _burned_for_villain[v1][i];
            } else {
                _burned_for_super[tokenid][i] = _burned_for_villain[v2][i-4];
            }
        }
        
    }

    // allows holders to burn their own tokens if desired
    function burn(uint256 tokenID) external {
        require(_msgSender() == ownerOf(tokenID));
        _burn(tokenID);
    }