// This contract is part of Zellic’s smart contract dataset, which is a collection of publicly available contract code gathered as of March 2023. | |
// File: @openzeppelin/contracts/utils/Address.sol | |
// OpenZeppelin Contracts (last updated v4.7.0) (utils/Address.sol) | |
pragma solidity ^0.8.1; | |
/** | |
* @dev Collection of functions related to the address type | |
*/ | |
library Address { | |
/** | |
* @dev Returns true if `account` is a contract. | |
* | |
* [IMPORTANT] | |
* ==== | |
* It is unsafe to assume that an address for which this function returns | |
* false is an externally-owned account (EOA) and not a contract. | |
* | |
* Among others, `isContract` will return false for the following | |
* 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 | |
* ==== | |
* | |
* [IMPORTANT] | |
* ==== | |
* You shouldn't rely on `isContract` to protect against flash loan attacks! | |
* | |
* Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets | |
* like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract | |
* constructor. | |
* ==== | |
*/ | |
function isContract(address account) internal view returns (bool) { | |
// This method relies on extcodesize/address.code.length, which returns 0 | |
// for contracts in construction, since the code is only stored at the end | |
// of the constructor execution. | |
return account.code.length > 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, "Address: unable to send value, recipient may have reverted"); | |
} | |
/** | |
* @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, "Address: low-level call with value failed"); | |
} | |
/** | |
* @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, "Address: insufficient balance for 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, "Address: low-level static call failed"); | |
} | |
/** | |
* @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), "Address: static call to 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, "Address: low-level delegate 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), "Address: delegate call to non-contract"); | |
(bool success, bytes memory returndata) = target.delegatecall(data); | |
return verifyCallResult(success, returndata, errorMessage); | |
} | |
/** | |
* @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the | |
* revert reason using the provided one. | |
* | |
* _Available since v4.3._ | |
*/ | |
function verifyCallResult( | |
bool success, | |
bytes memory returndata, | |
string memory errorMessage | |
) internal 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 | |
/// @solidity memory-safe-assembly | |
assembly { | |
let returndata_size := mload(returndata) | |
revert(add(32, returndata), returndata_size) | |
} | |
} else { | |
revert(errorMessage); | |
} | |
} | |
} | |
} | |
// File: @openzeppelin/contracts/token/ERC20/extensions/draft-IERC20Permit.sol | |
// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/draft-IERC20Permit.sol) | |
pragma solidity ^0.8.0; | |
/** | |
* @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in | |
* https://eips.ethereum.org/EIPS/eip-2612[EIP-2612]. | |
* | |
* Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by | |
* presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't | |
* need to send a transaction, and thus is not required to hold Ether at all. | |
*/ | |
interface IERC20Permit { | |
/** | |
* @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens, | |
* given ``owner``'s signed approval. | |
* | |
* IMPORTANT: The same issues {IERC20-approve} has related to transaction | |
* ordering also apply here. | |
* | |
* Emits an {Approval} event. | |
* | |
* Requirements: | |
* | |
* - `spender` cannot be the zero address. | |
* - `deadline` must be a timestamp in the future. | |
* - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner` | |
* over the EIP712-formatted function arguments. | |
* - the signature must use ``owner``'s current nonce (see {nonces}). | |
* | |
* For more information on the signature format, see the | |
* https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP | |
* section]. | |
*/ | |
function permit( | |
address owner, | |
address spender, | |
uint256 value, | |
uint256 deadline, | |
uint8 v, | |
bytes32 r, | |
bytes32 s | |
) external; | |
/** | |
* @dev Returns the current nonce for `owner`. This value must be | |
* included whenever a signature is generated for {permit}. | |
* | |
* Every successful call to {permit} increases ``owner``'s nonce by one. This | |
* prevents a signature from being used multiple times. | |
*/ | |
function nonces(address owner) external view returns (uint256); | |
/** | |
* @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}. | |
*/ | |
// solhint-disable-next-line func-name-mixedcase | |
function DOMAIN_SEPARATOR() external view returns (bytes32); | |
} | |
// File: @openzeppelin/contracts/security/ReentrancyGuard.sol | |
// OpenZeppelin Contracts (last updated v4.8.0) (security/ReentrancyGuard.sol) | |
pragma solidity ^0.8.0; | |
/** | |
* @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() { | |
_nonReentrantBefore(); | |
_; | |
_nonReentrantAfter(); | |
} | |
function _nonReentrantBefore() private { | |
// On the first call to nonReentrant, _status will be _NOT_ENTERED | |
require(_status != _ENTERED, "ReentrancyGuard: reentrant call"); | |
// Any calls to nonReentrant after this point will fail | |
_status = _ENTERED; | |
} | |
function _nonReentrantAfter() private { | |
// By storing the original value once again, a refund is triggered (see | |
// https://eips.ethereum.org/EIPS/eip-2200) | |
_status = _NOT_ENTERED; | |
} | |
} | |
// File: @openzeppelin/contracts/utils/introspection/IERC165.sol | |
// OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol) | |
pragma solidity ^0.8.0; | |
/** | |
* @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); | |
} | |
// File: @openzeppelin/contracts/token/ERC721/IERC721.sol | |
// OpenZeppelin Contracts (last updated v4.7.0) (token/ERC721/IERC721.sol) | |
pragma solidity ^0.8.0; | |
/** | |
* @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`. | |
* | |
* 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 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 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 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 the account approved for `tokenId` token. | |
* | |
* Requirements: | |
* | |
* - `tokenId` must exist. | |
*/ | |
function getApproved(uint256 tokenId) external view returns (address operator); | |
/** | |
* @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); | |
} | |
// File: @openzeppelin/contracts/token/ERC20/IERC20.sol | |
// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol) | |
pragma solidity ^0.8.0; | |
/** | |
* @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); | |
} | |
// File: @openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol | |
// OpenZeppelin Contracts (last updated v4.8.0) (token/ERC20/utils/SafeERC20.sol) | |
pragma solidity ^0.8.0; | |
/** | |
* @title SafeERC20 | |
* @dev Wrappers around ERC20 operations that throw on failure (when the token | |
* contract returns false). Tokens that return no value (and instead revert or | |
* throw on failure) are also supported, non-reverting calls are assumed to be | |
* successful. | |
* To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract, | |
* which allows you to call the safe operations as `token.safeTransfer(...)`, etc. | |
*/ | |
library SafeERC20 { | |
using Address for address; | |
function safeTransfer( | |
IERC20 token, | |
address to, | |
uint256 value | |
) internal { | |
_callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value)); | |
} | |
function safeTransferFrom( | |
IERC20 token, | |
address from, | |
address to, | |
uint256 value | |
) internal { | |
_callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value)); | |
} | |
/** | |
* @dev Deprecated. This function has issues similar to the ones found in | |
* {IERC20-approve}, and its usage is discouraged. | |
* | |
* Whenever possible, use {safeIncreaseAllowance} and | |
* {safeDecreaseAllowance} instead. | |
*/ | |
function safeApprove( | |
IERC20 token, | |
address spender, | |
uint256 value | |
) internal { | |
// safeApprove should only be called when setting an initial allowance, | |
// or when resetting it to zero. To increase and decrease it, use | |
// 'safeIncreaseAllowance' and 'safeDecreaseAllowance' | |
require( | |
(value == 0) || (token.allowance(address(this), spender) == 0), | |
"SafeERC20: approve from non-zero to non-zero allowance" | |
); | |
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value)); | |
} | |
function safeIncreaseAllowance( | |
IERC20 token, | |
address spender, | |
uint256 value | |
) internal { | |
uint256 newAllowance = token.allowance(address(this), spender) + value; | |
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance)); | |
} | |
function safeDecreaseAllowance( | |
IERC20 token, | |
address spender, | |
uint256 value | |
) internal { | |
unchecked { | |
uint256 oldAllowance = token.allowance(address(this), spender); | |
require(oldAllowance >= value, "SafeERC20: decreased allowance below zero"); | |
uint256 newAllowance = oldAllowance - value; | |
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance)); | |
} | |
} | |
function safePermit( | |
IERC20Permit token, | |
address owner, | |
address spender, | |
uint256 value, | |
uint256 deadline, | |
uint8 v, | |
bytes32 r, | |
bytes32 s | |
) internal { | |
uint256 nonceBefore = token.nonces(owner); | |
token.permit(owner, spender, value, deadline, v, r, s); | |
uint256 nonceAfter = token.nonces(owner); | |
require(nonceAfter == nonceBefore + 1, "SafeERC20: permit did not succeed"); | |
} | |
/** | |
* @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement | |
* on the return value: the return value is optional (but if data is returned, it must not be false). | |
* @param token The token targeted by the call. | |
* @param data The call data (encoded using abi.encode or one of its variants). | |
*/ | |
function _callOptionalReturn(IERC20 token, bytes memory data) private { | |
// We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since | |
// we're implementing it ourselves. We use {Address-functionCall} to perform this call, which verifies that | |
// the target address contains contract code and also asserts for success in the low-level call. | |
bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed"); | |
if (returndata.length > 0) { | |
// Return data is optional | |
require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed"); | |
} | |
} | |
} | |
// File: @openzeppelin/contracts/utils/Context.sol | |
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol) | |
pragma solidity ^0.8.0; | |
/** | |
* @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; | |
} | |
} | |
// File: @openzeppelin/contracts/access/Ownable.sol | |
// OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol) | |
pragma solidity ^0.8.0; | |
/** | |
* @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); | |
} | |
} | |
// File: contracts/WCAMundialStaking.sol | |
//SPDX-License-Identifier: MIT | |
pragma solidity ^0.8.17; | |
contract WCAMundialStaking is ReentrancyGuard, Ownable { | |
using SafeERC20 for IERC20; | |
// Interfaces for ERC721 and ERC20 | |
IERC721 public immutable nftCollection; | |
IERC20 public immutable rewardsToken; | |
// Constructor function to set the rewards token and the NFT collection addresses | |
constructor(IERC721 _nftCollection, IERC20 _rewardsToken) { | |
nftCollection = _nftCollection; | |
rewardsToken = _rewardsToken; | |
} | |
address public manager; | |
uint256 public startClaimTimestamp = 1685570400; // Jun 01 2023 | |
uint256 public startUnstakeTimestamp = 1671577200; // Dec 21 2022 | |
uint256 public endRewardsTimestamp = 1676761200; // Feb 19 2023 | |
// Almost 20 Token rewards per day => 0.00023149 * 10**18 | |
uint256 public rewardsPerSeconds = 231490000000000; | |
uint256 public rewardExponent = 10**10; | |
// Rewards have vesting of 0.13% per day => 0.00000154% per second => 1.54 * 10^-8 => 154 * 10^-10 | |
uint256 public rewardsLockSeconds = 154; | |
bool public _stakingLive = false; | |
mapping(uint256 => uint256) public tokenIdTimeStaked; | |
mapping(uint256 => address) public tokenIdToStaker; | |
mapping(address => uint256[]) public stakerToTokenIds; | |
mapping(address => uint256) public stakerRewards; | |
mapping(address => uint256) public stakerRewardsClaimed; | |
// Modifiers | |
modifier onlyOwnerOrManager() { | |
require(owner() == msg.sender || manager == msg.sender, "Unauthorized"); | |
_; | |
} | |
modifier canClaim() { | |
require(block.timestamp >= startClaimTimestamp, "You can't already claim your rewards"); | |
_; | |
} | |
modifier canUnstake() { | |
require(block.timestamp >= startUnstakeTimestamp, "You can't already unstake your NFTs"); | |
_; | |
} | |
modifier stakingIsLive() { | |
require(_stakingLive, "Staking isn't live"); | |
_; | |
} | |
function setManager(address _manager) external onlyOwner { | |
manager = _manager; | |
} | |
function setRewardsPerSecond(uint256 _rewardsPerSeconds) external onlyOwnerOrManager { | |
rewardsPerSeconds = _rewardsPerSeconds; | |
} | |
function setRewardExponent(uint256 _rewardExponent) external onlyOwnerOrManager { | |
rewardExponent = _rewardExponent; | |
} | |
function setStartClaimTimestamp(uint256 _timestamp) external onlyOwnerOrManager { | |
require(_timestamp >= endRewardsTimestamp, "Start claim timestamp must be after end rewards timestamp"); | |
startClaimTimestamp = _timestamp; | |
} | |
function setEndRewardsTimestamp(uint256 _timestamp) external onlyOwnerOrManager { | |
endRewardsTimestamp = _timestamp; | |
} | |
function setStartUnstakeTimestamp(uint256 _timestamp) external onlyOwnerOrManager { | |
startUnstakeTimestamp = _timestamp; | |
} | |
function toggleStakingLive() external onlyOwnerOrManager { | |
_stakingLive = !_stakingLive; | |
} | |
function bonus(address _address, uint256 _bonus) external onlyOwnerOrManager { | |
stakerRewards[_address] += _bonus; | |
} | |
function reduce(address _address, uint256 _reduce) external onlyOwnerOrManager { | |
stakerRewards[_address] -= _reduce; | |
} | |
function getTotalRewards(address staker) public view returns (uint256) { | |
return getAvailableRewards(staker) + stakerRewardsClaimed[staker]; | |
} | |
function getStakedCount(address staker) external view returns (uint256) { | |
return stakerToTokenIds[staker].length; | |
} | |
function getStakedTokens(address staker) external view returns (uint256[] memory) { | |
return stakerToTokenIds[staker]; | |
} | |
function stakeByIds(uint256[] calldata tokenIds) external stakingIsLive { | |
for (uint256 i = 0; i < tokenIds.length; i++) { | |
uint256 tokenId = tokenIds[i]; | |
require(nftCollection.ownerOf(tokenId) == msg.sender && tokenIdToStaker[tokenId] == address(0), "You don't own this token!"); | |
nftCollection.transferFrom(msg.sender, address(this), tokenId); | |
stakerToTokenIds[msg.sender].push(tokenId); | |
tokenIdTimeStaked[tokenId] = block.timestamp; | |
tokenIdToStaker[tokenId] = msg.sender; | |
} | |
} | |
function removeTokenIdFromArray(uint256[] storage array, uint256 tokenId) internal { | |
uint256 length = array.length; | |
for (uint256 i = 0; i < length; i++) { | |
if (array[i] == tokenId) { | |
length--; | |
if (i < length) { | |
array[i] = array[length]; | |
} | |
array.pop(); | |
break; | |
} | |
} | |
} | |
function unstakeByIds(uint256[] calldata tokenIds) public canUnstake nonReentrant { | |
for (uint256 i = 0; i < tokenIds.length; i++) { | |
uint256 tokenId = tokenIds[i]; | |
require(tokenIdToStaker[tokenId] == msg.sender, "You don't own this token!"); | |
stakerRewards[msg.sender] += getRewardsByTokenId(tokenId); | |
removeTokenIdFromArray(stakerToTokenIds[msg.sender], tokenId); | |
tokenIdToStaker[tokenId] = address(0); | |
nftCollection.transferFrom(address(this), msg.sender, tokenId); | |
} | |
} | |
function getRewardsByTokenId(uint256 _tokenId) public view returns (uint256) { | |
uint256 timestamp = block.timestamp; | |
if (tokenIdToStaker[_tokenId] == address(0) || tokenIdTimeStaked[_tokenId] > endRewardsTimestamp) { | |
return 0; | |
} | |
if (timestamp > endRewardsTimestamp) { | |
timestamp = endRewardsTimestamp; | |
} | |
return ((timestamp - tokenIdTimeStaked[_tokenId]) * rewardsPerSeconds); | |
} | |
function getAvailableRewards(address _staker) public view returns (uint256) { | |
uint256 tokenRewards = 0; | |
for (uint256 i = stakerToTokenIds[_staker].length; i > 0; i--) { | |
uint256 tokenId = stakerToTokenIds[msg.sender][i - 1]; | |
tokenRewards += getRewardsByTokenId(tokenId); | |
} | |
if (tokenRewards == 0 && stakerRewards[_staker] == 0) { | |
return 0; | |
} | |
uint256 availableRewards = stakerRewards[_staker] + tokenRewards - stakerRewardsClaimed[_staker]; | |
return availableRewards; | |
} | |
function getClaimableRewards(address _staker) public view returns (uint256) { | |
// Calculate the percentage of rewards to unlock based on the time passed since the start of the claim | |
if (block.timestamp < startClaimTimestamp) { | |
return 0; | |
} | |
uint256 totalRewards = getTotalRewards(_staker); | |
uint256 secondsFromClaimStart = block.timestamp - startClaimTimestamp; | |
uint256 rewardsToUnlock = ((totalRewards / rewardExponent) * secondsFromClaimStart * rewardsLockSeconds) - stakerRewardsClaimed[_staker]; | |
// If the rewards to unlock are more than the total rewards, return the total rewards | |
if (rewardsToUnlock > totalRewards) { | |
return totalRewards; | |
} | |
require(rewardsToUnlock <= totalRewards, "You can't claim more than you have"); | |
// Else return the rewards to unlock | |
return rewardsToUnlock; | |
} | |
function claimRewards() external canClaim nonReentrant { | |
uint256 rewardsToUnlock = getClaimableRewards(msg.sender); | |
// Require that the sender has claimed in the past | |
require(rewardsToUnlock > 0, "You have no rewards to claim"); | |
stakerRewardsClaimed[msg.sender] += rewardsToUnlock; | |
// Send token from owner to staker | |
rewardsToken.transferFrom(owner(), msg.sender, rewardsToUnlock); | |
} | |
} |