/**
 *Submitted for verification at Etherscan.io on 2022-02-27
*/

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @dev String operations.
 */
library Strings {
	bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef";

	/**
	 * @dev Converts a `uint256` to its ASCII `string` decimal representation.
	 */
	function toString(uint256 value) internal pure returns (string memory) {
		// Inspired by OraclizeAPI's implementation - MIT licence
		// https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol

		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);
	}

	/**
	 * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
	 */
	function toHexString(uint256 value) internal pure returns (string memory) {
		if (value == 0) {
			return "0x00";
		}
		uint256 temp = value;
		uint256 length = 0;
		while (temp != 0) {
			length++;
			temp >>= 8;
		}
		return toHexString(value, length);
	}

	/**
	 * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
	 */
	function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
		bytes memory buffer = new bytes(2 * length + 2);
		buffer[0] = "0";
		buffer[1] = "x";
		for (uint256 i = 2 * length + 1; i > 1; --i) {
			buffer[i] = _HEX_SYMBOLS[value & 0xf];
			value >>= 4;
		}
		require(value == 0, "Strings: hex length insufficient");
		return string(buffer);
	}
}

/**
 * @dev Interface of the ERC165 standard, as defined in the
 * https://eips.ethereum.org/EIPS/eip-165[EIP].
 *
 * Implementers can declare support of contract interfaces, which can then be
 * queried by others ({ERC165Checker}).
 *
 * For an implementation, see {ERC165}.
 */
interface IERC165 {
	/**
	 * @dev Returns true if this contract implements the interface defined by
	 * `interfaceId`. See the corresponding
	 * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
	 * to learn more about how these ids are created.
	 *
	 * This function call must use less than 30 000 gas.
	 */
	function supportsInterface(bytes4 interfaceId) external view returns (bool);
}

/**
 * @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 that helps prevent reentrant calls to a function.
 *
 * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
 * available, which can be applied to functions to make sure there are no nested
 * (reentrant) calls to them.
 *
 * Note that because there is a single `nonReentrant` guard, functions marked as
 * `nonReentrant` may not call one another. This can be worked around by making
 * those functions `private`, and then adding `external` `nonReentrant` entry
 * points to them.
 *
 * TIP: If you would like to learn more about reentrancy and alternative ways
 * to protect against it, check out our blog post
 * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
 */
abstract contract ReentrancyGuard {
	// Booleans are more expensive than uint256 or any type that takes up a full
	// word because each write operation emits an extra SLOAD to first read the
	// slot's contents, replace the bits taken up by the boolean, and then write
	// back. This is the compiler's defense against contract upgrades and
	// pointer aliasing, and it cannot be disabled.

	// The values being non-zero value makes deployment a bit more expensive,
	// but in exchange the refund on every call to nonReentrant will be lower in
	// amount. Since refunds are capped to a percentage of the total
	// transaction's gas, it is best to keep them low in cases like this one, to
	// increase the likelihood of the full refund coming into effect.
	uint256 private constant _NOT_ENTERED = 1;
	uint256 private constant _ENTERED = 2;

	uint256 private _status;

	constructor() {
		_status = _NOT_ENTERED;
	}

	/**
	 * @dev Prevents a contract from calling itself, directly or indirectly.
	 * Calling a `nonReentrant` function from another `nonReentrant`
	 * function is not supported. It is possible to prevent this from happening
	 * by making the `nonReentrant` function external, and making it call a
	 * `private` function that does the actual work.
	 */
	modifier nonReentrant() {
		// On the first call to nonReentrant, _notEntered will be true
		require(_status != _ENTERED, "ReentrancyGuard: reentrant call");

		// Any calls to nonReentrant after this point will fail
		_status = _ENTERED;

		_;

		// By storing the original value once again, a refund is triggered (see
		// https://eips.ethereum.org/EIPS/eip-2200)
		_status = _NOT_ENTERED;
	}
}

/**
 * @dev Elliptic Curve Digital Signature Algorithm (ECDSA) operations.
 *
 * These functions can be used to verify that a message was signed by the holder
 * of the private keys of a given address.
 */
library ECDSA {
	enum RecoverError {
		NoError,
		InvalidSignature,
		InvalidSignatureLength,
		InvalidSignatureS,
		InvalidSignatureV
	}

	function _throwError(RecoverError error) private pure {
		if (error == RecoverError.NoError) {
			return; // no error: do nothing
		} else if (error == RecoverError.InvalidSignature) {
			revert("ECDSA: invalid signature");
		} else if (error == RecoverError.InvalidSignatureLength) {
			revert("ECDSA: invalid signature length");
		} else if (error == RecoverError.InvalidSignatureS) {
			revert("ECDSA: invalid signature 's' value");
		} else if (error == RecoverError.InvalidSignatureV) {
			revert("ECDSA: invalid signature 'v' value");
		}
	}

	/**
	 * @dev Returns the address that signed a hashed message (`hash`) with
	 * `signature` or error string. This address can then be used for verification purposes.
	 *
	 * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
	 * this function rejects them by requiring the `s` value to be in the lower
	 * half order, and the `v` value to be either 27 or 28.
	 *
	 * IMPORTANT: `hash` _must_ be the result of a hash operation for the
	 * verification to be secure: it is possible to craft signatures that
	 * recover to arbitrary addresses for non-hashed data. A safe way to ensure
	 * this is by receiving a hash of the original message (which may otherwise
	 * be too long), and then calling {toEthSignedMessageHash} on it.
	 *
	 * Documentation for signature generation:
	 * - with https://web3js.readthedocs.io/en/v1.3.4/web3-eth-accounts.html#sign[Web3.js]
	 * - with https://docs.ethers.io/v5/api/signer/#Signer-signMessage[ethers]
	 *
	 * _Available since v4.3._
	 */
	function tryRecover(bytes32 hash, bytes memory signature) internal pure returns (address, RecoverError) {
		// Check the signature length
		// - case 65: r,s,v signature (standard)
		// - case 64: r,vs signature (cf https://eips.ethereum.org/EIPS/eip-2098) _Available since v4.1._
		if (signature.length == 65) {
			bytes32 r;
			bytes32 s;
			uint8 v;
			// ecrecover takes the signature parameters, and the only way to get them
			// currently is to use assembly.
			assembly {
				r := mload(add(signature, 0x20))
				s := mload(add(signature, 0x40))
				v := byte(0, mload(add(signature, 0x60)))
			}
			return tryRecover(hash, v, r, s);
		} else if (signature.length == 64) {
			bytes32 r;
			bytes32 vs;
			// ecrecover takes the signature parameters, and the only way to get them
			// currently is to use assembly.
			assembly {
				r := mload(add(signature, 0x20))
				vs := mload(add(signature, 0x40))
			}
			return tryRecover(hash, r, vs);
		} else {
			return (address(0), RecoverError.InvalidSignatureLength);
		}
	}

	/**
	 * @dev Returns the address that signed a hashed message (`hash`) with
	 * `signature`. This address can then be used for verification purposes.
	 *
	 * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
	 * this function rejects them by requiring the `s` value to be in the lower
	 * half order, and the `v` value to be either 27 or 28.
	 *
	 * IMPORTANT: `hash` _must_ be the result of a hash operation for the
	 * verification to be secure: it is possible to craft signatures that
	 * recover to arbitrary addresses for non-hashed data. A safe way to ensure
	 * this is by receiving a hash of the original message (which may otherwise
	 * be too long), and then calling {toEthSignedMessageHash} on it.
	 */
	function recover(bytes32 hash, bytes memory signature) internal pure returns (address) {
		(address recovered, RecoverError error) = tryRecover(hash, signature);
		_throwError(error);
		return recovered;
	}

	/**
	 * @dev Overload of {ECDSA-tryRecover} that receives the `r` and `vs` short-signature fields separately.
	 *
	 * See https://eips.ethereum.org/EIPS/eip-2098[EIP-2098 short signatures]
	 *
	 * _Available since v4.3._
	 */
	function tryRecover(
		bytes32 hash,
		bytes32 r,
		bytes32 vs
	) internal pure returns (address, RecoverError) {
		bytes32 s;
		uint8 v;
		assembly {
			s := and(vs, 0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff)
			v := add(shr(255, vs), 27)
		}
		return tryRecover(hash, v, r, s);
	}

	/**
	 * @dev Overload of {ECDSA-recover} that receives the `r and `vs` short-signature fields separately.
	 *
	 * _Available since v4.2._
	 */
	function recover(
		bytes32 hash,
		bytes32 r,
		bytes32 vs
	) internal pure returns (address) {
		(address recovered, RecoverError error) = tryRecover(hash, r, vs);
		_throwError(error);
		return recovered;
	}

	/**
	 * @dev Overload of {ECDSA-tryRecover} that receives the `v`,
	 * `r` and `s` signature fields separately.
	 *
	 * _Available since v4.3._
	 */
	function tryRecover(
		bytes32 hash,
		uint8 v,
		bytes32 r,
		bytes32 s
	) internal pure returns (address, RecoverError) {
		// EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
		// unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
		// the valid range for s in (301): 0 < s < secp256k1n ÷ 2 + 1, and for v in (302): v ∈ {27, 28}. Most
		// signatures from current libraries generate a unique signature with an s-value in the lower half order.
		//
		// If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
		// with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
		// vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
		// these malleable signatures as well.
		if (uint256(s) > 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0) {
			return (address(0), RecoverError.InvalidSignatureS);
		}
		if (v != 27 && v != 28) {
			return (address(0), RecoverError.InvalidSignatureV);
		}

		// If the signature is valid (and not malleable), return the signer address
		address signer = ecrecover(hash, v, r, s);
		if (signer == address(0)) {
			return (address(0), RecoverError.InvalidSignature);
		}

		return (signer, RecoverError.NoError);
	}

	/**
	 * @dev Overload of {ECDSA-recover} that receives the `v`,
	 * `r` and `s` signature fields separately.
	 */
	function recover(
		bytes32 hash,
		uint8 v,
		bytes32 r,
		bytes32 s
	) internal pure returns (address) {
		(address recovered, RecoverError error) = tryRecover(hash, v, r, s);
		_throwError(error);
		return recovered;
	}

	/**
	 * @dev Returns an Ethereum Signed Message, created from a `hash`. This
	 * produces hash corresponding to the one signed with the
	 * https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
	 * JSON-RPC method as part of EIP-191.
	 *
	 * See {recover}.
	 */
	function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32) {
		// 32 is the length in bytes of hash,
		// enforced by the type signature above
		return keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n32", hash));
	}

	/**
	 * @dev Returns an Ethereum Signed Message, created from `s`. This
	 * produces hash corresponding to the one signed with the
	 * https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
	 * JSON-RPC method as part of EIP-191.
	 *
	 * See {recover}.
	 */
	function toEthSignedMessageHash(bytes memory s) internal pure returns (bytes32) {
		return keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n", Strings.toString(s.length), s));
	}

	/**
	 * @dev Returns an Ethereum Signed Typed Data, created from a
	 * `domainSeparator` and a `structHash`. This produces hash corresponding
	 * to the one signed with the
	 * https://eips.ethereum.org/EIPS/eip-712[`eth_signTypedData`]
	 * JSON-RPC method as part of EIP-712.
	 *
	 * See {recover}.
	 */
	function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash) internal pure returns (bytes32) {
		return keccak256(abi.encodePacked("\x19\x01", domainSeparator, structHash));
	}
}

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
	/**
	 * @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 `recipient`.
	 *
	 * Returns a boolean value indicating whether the operation succeeded.
	 *
	 * Emits a {Transfer} event.
	 */
	function transfer(address recipient, 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 `sender` to `recipient` 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 sender,
		address recipient,
		uint256 amount
	) external returns (bool);

	/**
	 * @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 Required interface of an ERC721 compliant contract.
 */
interface IERC721 is IERC165 {
	/**
	 * @dev Emitted when `tokenId` token is transferred from `from` to `to`.
	 */
	event Transfer(address indexed from, address indexed to, uint256 indexed tokenId);

	/**
	 * @dev Emitted when `owner` enables `approved` to manage the `tokenId` token.
	 */
	event Approval(address indexed owner, address indexed approved, uint256 indexed tokenId);

	/**
	 * @dev Emitted when `owner` enables or disables (`approved`) `operator` to manage all of its assets.
	 */
	event ApprovalForAll(address indexed owner, address indexed operator, bool approved);

	/**
	 * @dev Returns the number of tokens in ``owner``'s account.
	 */
	function balanceOf(address owner) external view returns (uint256 balance);

	/**
	 * @dev Returns the owner of the `tokenId` token.
	 *
	 * Requirements:
	 *
	 * - `tokenId` must exist.
	 */
	function ownerOf(uint256 tokenId) external view returns (address owner);

	/**
	 * @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
	 * are aware of the ERC721 protocol to prevent tokens from being forever locked.
	 *
	 * Requirements:
	 *
	 * - `from` cannot be the zero address.
	 * - `to` cannot be the zero address.
	 * - `tokenId` token must exist and be owned by `from`.
	 * - If the caller is not `from`, it must be have been allowed to move this token by either {approve} or {setApprovalForAll}.
	 * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
	 *
	 * Emits a {Transfer} event.
	 */
	function safeTransferFrom(
		address from,
		address to,
		uint256 tokenId
	) external;

	/**
	 * @dev Transfers `tokenId` token from `from` to `to`.
	 *
	 * WARNING: Usage of this method is discouraged, use {safeTransferFrom} whenever possible.
	 *
	 * Requirements:
	 *
	 * - `from` cannot be the zero address.
	 * - `to` cannot be the zero address.
	 * - `tokenId` token must be owned by `from`.
	 * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
	 *
	 * Emits a {Transfer} event.
	 */
	function transferFrom(
		address from,
		address to,
		uint256 tokenId
	) external;

	/**
	 * @dev Gives permission to `to` to transfer `tokenId` token to another account.
	 * The approval is cleared when the token is transferred.
	 *
	 * Only a single account can be approved at a time, so approving the zero address clears previous approvals.
	 *
	 * Requirements:
	 *
	 * - The caller must own the token or be an approved operator.
	 * - `tokenId` must exist.
	 *
	 * Emits an {Approval} event.
	 */
	function approve(address to, uint256 tokenId) external;

	/**
	 * @dev Returns the account approved for `tokenId` token.
	 *
	 * Requirements:
	 *
	 * - `tokenId` must exist.
	 */
	function getApproved(uint256 tokenId) external view returns (address operator);

	/**
	 * @dev Approve or remove `operator` as an operator for the caller.
	 * Operators can call {transferFrom} or {safeTransferFrom} for any token owned by the caller.
	 *
	 * Requirements:
	 *
	 * - The `operator` cannot be the caller.
	 *
	 * Emits an {ApprovalForAll} event.
	 */
	function setApprovalForAll(address operator, bool _approved) external;

	/**
	 * @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.
	 *
	 * See {setApprovalForAll}
	 */
	function isApprovedForAll(address owner, address operator) external view returns (bool);

	/**
	 * @dev Safely transfers `tokenId` token from `from` to `to`.
	 *
	 * Requirements:
	 *
	 * - `from` cannot be the zero address.
	 * - `to` cannot be the zero address.
	 * - `tokenId` token must exist and be owned by `from`.
	 * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
	 * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
	 *
	 * Emits a {Transfer} event.
	 */
	function safeTransferFrom(
		address from,
		address to,
		uint256 tokenId,
		bytes calldata data
	) external;
}

/**
 * @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 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 {
		_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);
	}
}

contract WastedWorld is Ownable, ReentrancyGuard {
	uint256 public constant SECONDS_IN_DAY = 24 * 60 * 60;
	uint256 public constant ACCELERATED_YIELD_DAYS = 2;
	uint256 public constant ACCELERATED_YIELD_MULTIPLIER = 2;
	uint256 public acceleratedYield;

	address public signerAddress;
	address[] public authorisedLog;

	bool public stakingLaunched;
	bool public depositPaused;

	struct Staker {
	  uint256 currentYield;
	  uint256 accumulatedAmount;
	  uint256 lastCheckpoint;
	}

	mapping(address => bool) isWWNftContract;
	mapping(address => mapping(address => uint256[])) stakedTokensForAddress;
	mapping(address => uint256) public _baseRates;
	mapping(address => Staker) private _stakers;
	mapping(address => mapping(uint256 => address)) private _ownerOfToken;
	mapping(address => mapping(uint256 => uint256)) private _tokensMultiplier;
	mapping(address => bool) private _authorised;

	event Deposit(address indexed staker,address contractAddress,uint256 tokensAmount);
	event Withdraw(address indexed staker,address contractAddress,uint256 tokensAmount);
	event AutoDeposit(address indexed contractAddress,uint256 tokenId,address indexed owner);
	event WithdrawStuckERC721(address indexed receiver, address indexed tokenAddress, uint256 indexed tokenId);

	constructor(
	  address _pre,
	  address _signer
	) {
		_baseRates[_pre] = 4200 ether;
		isWWNftContract[_pre] = true;

		signerAddress = _signer;
	}

	modifier authorised() {
	  require(_authorised[_msgSender()], "The token contract is not authorised");
		_;
	}

	function deposit(
	  address contractAddress,
	  uint256[] memory tokenIds,
	  uint256[] memory tokenTraits,
	  bytes calldata signature
	) public nonReentrant {
	  require(!depositPaused, "Deposit paused");
	  require(stakingLaunched, "Staking is not launched yet");
	  require(
		contractAddress != address(0) &&
		isWWNftContract[contractAddress],
		"Unknown contract"
	  );

	  if (tokenTraits.length > 0) {
		require(_validateSignature(
		  signature,
		  contractAddress,
		  tokenIds,
		  tokenTraits
		), "Invalid data provided");
		_setTokensValues(contractAddress, tokenIds, tokenTraits);
	  }

	  Staker storage user = _stakers[_msgSender()];
	  uint256 newYield = user.currentYield;

	  for (uint256 i; i < tokenIds.length; i++) {
		require(IERC721(contractAddress).ownerOf(tokenIds[i]) == _msgSender(), "Not the owner");
		IERC721(contractAddress).safeTransferFrom(_msgSender(), address(this), tokenIds[i]);

		_ownerOfToken[contractAddress][tokenIds[i]] = _msgSender();

		newYield += getTokenYield(contractAddress, tokenIds[i]);
		stakedTokensForAddress[_msgSender()][contractAddress].push(tokenIds[i]);
	  }

	  accumulate(_msgSender());
	  user.currentYield = newYield;

	  emit Deposit(_msgSender(), contractAddress, tokenIds.length);
	}

	function withdraw(
	  address contractAddress,
	  uint256[] memory tokenIds
	) public nonReentrant {
	  require(
		contractAddress != address(0) &&
		isWWNftContract[contractAddress],
		"Unknown contract"
	  );
	  Staker storage user = _stakers[_msgSender()];
	  uint256 newYield = user.currentYield;

	  for (uint256 i; i < tokenIds.length; i++) {
		require(IERC721(contractAddress).ownerOf(tokenIds[i]) == address(this), "Not the owner");

		_ownerOfToken[contractAddress][tokenIds[i]] = address(0);

		if (user.currentYield != 0) {
		  uint256 tokenYield = getTokenYield(contractAddress, tokenIds[i]);
		  newYield -= tokenYield;
		}

		stakedTokensForAddress[_msgSender()][contractAddress] = _moveTokenInTheList(stakedTokensForAddress[_msgSender()][contractAddress], tokenIds[i]);
		stakedTokensForAddress[_msgSender()][contractAddress].pop();

		IERC721(contractAddress).safeTransferFrom(address(this), _msgSender(), tokenIds[i]);
	  }

	  accumulate(_msgSender());
	  user.currentYield = newYield;

	  emit Withdraw(_msgSender(), contractAddress, tokenIds.length);
	}

	function registerDeposit(address owner, address contractAddress, uint256 tokenId) public authorised {
	  require(
		contractAddress != address(0) &&
		isWWNftContract[contractAddress],
		"Unknown contract"
	  );
	  require(IERC721(contractAddress).ownerOf(tokenId) == address(this), "!Owner");
	  require(ownerOf(contractAddress, tokenId) == address(0), "Already deposited");

	  _ownerOfToken[contractAddress][tokenId] = owner;

	  Staker storage user = _stakers[owner];
	  uint256 newYield = user.currentYield;

	  newYield += getTokenYield(contractAddress, tokenId);
	  stakedTokensForAddress[owner][contractAddress].push(tokenId);

	  accumulate(owner);
	  user.currentYield = newYield;

	  emit AutoDeposit(contractAddress, tokenId, _msgSender());
	}

	function getAccumulatedAmount(address staker) external view returns (uint256) {
	  return _stakers[staker].accumulatedAmount + getCurrentReward(staker);
	}

	function getTokenYield(address contractAddress, uint256 tokenId) public view returns (uint256) {
	  uint256 tokenYield = _tokensMultiplier[contractAddress][tokenId];
	  if (tokenYield == 0) { tokenYield = _baseRates[contractAddress]; }

	  return tokenYield;
	}

	function getStakerYield(address staker) public view returns (uint256) {
	  return _stakers[staker].currentYield;
	}

	function getStakerTokens(address staker, address contractAddress) public view returns (uint256[] memory) {
	  return (stakedTokensForAddress[staker][contractAddress]);
	}

	function isMultiplierSet(address contractAddress, uint256 tokenId) public view returns (bool) {
	  return _tokensMultiplier[contractAddress][tokenId] > 0;
	}

	function _moveTokenInTheList(uint256[] memory list, uint256 tokenId) internal pure returns (uint256[] memory) {
	  uint256 tokenIndex = 0;
	  uint256 lastTokenIndex = list.length - 1;
	  uint256 length = list.length;

	  for(uint256 i = 0; i < length; i++) {
		if (list[i] == tokenId) {
		  tokenIndex = i + 1;
		  break;
		}
	  }
	  require(tokenIndex != 0, "msg.sender is not the owner");

	  tokenIndex -= 1;

	  if (tokenIndex != lastTokenIndex) {
		list[tokenIndex] = list[lastTokenIndex];
		list[lastTokenIndex] = tokenId;
	  }

	  return list;
	}

	function _validateSignature(
	  bytes calldata signature,
	  address contractAddress,
	  uint256[] memory tokenIds,
	  uint256[] memory tokenTraits
	  ) internal view returns (bool) {
	  bytes32 dataHash = keccak256(abi.encodePacked(contractAddress, tokenIds, tokenTraits));
	  bytes32 message = ECDSA.toEthSignedMessageHash(dataHash);

	  address receivedAddress = ECDSA.recover(message, signature);
	  return (receivedAddress != address(0) && receivedAddress == signerAddress);
	}

	function _setTokensValues(
	  address contractAddress,
	  uint256[] memory tokenIds,
	  uint256[] memory tokenTraits
	) internal {
	  require(tokenIds.length == tokenTraits.length, "Wrong arrays provided");
	  for (uint256 i; i < tokenIds.length; i++) {
		if (tokenTraits[i] != 0 && tokenTraits[i] <= 8000 ether) {
		  _tokensMultiplier[contractAddress][tokenIds[i]] = tokenTraits[i];
		}
	  }
	}

	function getCurrentReward(address staker) public view returns (uint256) {
	  Staker memory user = _stakers[staker];
	  if (user.lastCheckpoint == 0) { return 0; }
	  if (user.lastCheckpoint < acceleratedYield && block.timestamp < acceleratedYield) {
		return (block.timestamp - user.lastCheckpoint) * user.currentYield / SECONDS_IN_DAY * ACCELERATED_YIELD_MULTIPLIER;
	  }
	  if (user.lastCheckpoint < acceleratedYield && block.timestamp > acceleratedYield) {
		uint256 currentReward;
		currentReward += (acceleratedYield - user.lastCheckpoint) * user.currentYield / SECONDS_IN_DAY * ACCELERATED_YIELD_MULTIPLIER;
		currentReward += (block.timestamp - acceleratedYield) * user.currentYield / SECONDS_IN_DAY;
		return currentReward;
	  }
	  return (block.timestamp - user.lastCheckpoint) * user.currentYield / SECONDS_IN_DAY;
	}

	function accumulate(address staker) internal {
	  _stakers[staker].accumulatedAmount += getCurrentReward(staker);
	  _stakers[staker].lastCheckpoint = block.timestamp;
	}

	/**
	* @dev Returns token owner address (returns address(0) if token is not inside the gateway)
	*/
	function ownerOf(address contractAddress, uint256 tokenId) public view returns (address) {
	  return _ownerOfToken[contractAddress][tokenId];
	}

	function addNFTContract(address _contract, uint256 _baseReward) public onlyOwner {
	  _baseRates[_contract] = _baseReward;
	  isWWNftContract[_contract] = true;
	}

	/**
	* @dev Admin function to authorise the contract address
	*/
	function authorise(address toAuth) public onlyOwner {
	  _authorised[toAuth] = true;
	  authorisedLog.push(toAuth);
	}

	/**
	* @dev Function allows admin add unauthorised address.
	*/
	function unauthorise(address addressToUnAuth) public onlyOwner {
	  _authorised[addressToUnAuth] = false;
	}

	/**
	* @dev Function allows admin withdraw ERC721 in case of emergency.
	*/
	function emergencyWithdraw(address tokenAddress, uint256[] memory tokenIds) public onlyOwner {
	  require(tokenIds.length <= 50, "50 is max per tx");
	  pauseDeposit(true);
	  for (uint256 i; i < tokenIds.length; i++) {
		address receiver = _ownerOfToken[tokenAddress][tokenIds[i]];
		if (receiver != address(0) && IERC721(tokenAddress).ownerOf(tokenIds[i]) == address(this)) {
		  IERC721(tokenAddress).transferFrom(address(this), receiver, tokenIds[i]);
		  emit WithdrawStuckERC721(receiver, tokenAddress, tokenIds[i]);
		}
	  }
	}

	/**
	* @dev Function allows to pause deposits if needed. Withdraw remains active.
	*/
	function pauseDeposit(bool _pause) public onlyOwner {
	  depositPaused = _pause;
	}

	/**
	* @dev Function allows to pause deposits if needed. Withdraw remains active.
	*/
	function updateSignerAddress(address _signer) public onlyOwner {
	  signerAddress = _signer;
	}

	function launchStaking() public onlyOwner {
	  require(!stakingLaunched, "Staking has been launched already");
	  stakingLaunched = true;
	  acceleratedYield = block.timestamp + (SECONDS_IN_DAY * ACCELERATED_YIELD_DAYS);
	}

	function updateBaseYield(address _contract, uint256 _yield) public onlyOwner {
	  _baseRates[_contract] = _yield;
	}

	function onERC721Received(address, address, uint256, bytes calldata) external pure returns(bytes4){
	  return bytes4(keccak256("onERC721Received(address,address,uint256,bytes)"));
	}
}

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