// SPDX-License-Identifier: MIT// OpenZeppelin Contracts (last updated v4.8.0) (utils/Address.sol)pragmasolidity ^0.8.1;/**
* @dev Collection of functions related to the address type
*/libraryAddress{
/**
* @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.
* ====
*/functionisContract(address account) internalviewreturns (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].
*/functionsendValue(addresspayable 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._
*/functionfunctionCall(address target, bytesmemory data) internalreturns (bytesmemory) {
return functionCallWithValue(target, data, 0, "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._
*/functionfunctionCall(address target,
bytesmemory data,
stringmemory errorMessage
) internalreturns (bytesmemory) {
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._
*/functionfunctionCallWithValue(address target,
bytesmemory data,
uint256 value
) internalreturns (bytesmemory) {
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._
*/functionfunctionCallWithValue(address target,
bytesmemory data,
uint256 value,
stringmemory errorMessage
) internalreturns (bytesmemory) {
require(address(this).balance>= value, "Address: insufficient balance for call");
(bool success, bytesmemory returndata) = target.call{value: value}(data);
return verifyCallResultFromTarget(target, success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/functionfunctionStaticCall(address target, bytesmemory data) internalviewreturns (bytesmemory) {
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._
*/functionfunctionStaticCall(address target,
bytesmemory data,
stringmemory errorMessage
) internalviewreturns (bytesmemory) {
(bool success, bytesmemory returndata) = target.staticcall(data);
return verifyCallResultFromTarget(target, success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a delegate call.
*
* _Available since v3.4._
*/functionfunctionDelegateCall(address target, bytesmemory data) internalreturns (bytesmemory) {
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._
*/functionfunctionDelegateCall(address target,
bytesmemory data,
stringmemory errorMessage
) internalreturns (bytesmemory) {
(bool success, bytesmemory returndata) = target.delegatecall(data);
return verifyCallResultFromTarget(target, success, returndata, errorMessage);
}
/**
* @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
* the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
*
* _Available since v4.8._
*/functionverifyCallResultFromTarget(address target,
bool success,
bytesmemory returndata,
stringmemory errorMessage
) internalviewreturns (bytesmemory) {
if (success) {
if (returndata.length==0) {
// only check isContract if the call was successful and the return data is empty// otherwise we already know that it was a contractrequire(isContract(target), "Address: call to non-contract");
}
return returndata;
} else {
_revert(returndata, errorMessage);
}
}
/**
* @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
* revert reason or using the provided one.
*
* _Available since v4.3._
*/functionverifyCallResult(bool success,
bytesmemory returndata,
stringmemory errorMessage
) internalpurereturns (bytesmemory) {
if (success) {
return returndata;
} else {
_revert(returndata, errorMessage);
}
}
function_revert(bytesmemory returndata, stringmemory errorMessage) privatepure{
// Look for revert reason and bubble it up if presentif (returndata.length>0) {
// The easiest way to bubble the revert reason is using memory via assembly/// @solidity memory-safe-assemblyassembly {
let returndata_size :=mload(returndata)
revert(add(32, returndata), returndata_size)
}
} else {
revert(errorMessage);
}
}
}
Contract Source Code
File 2 of 23: Context.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)pragmasolidity ^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.
*/abstractcontractContext{
function_msgSender() internalviewvirtualreturns (address) {
returnmsg.sender;
}
function_msgData() internalviewvirtualreturns (bytescalldata) {
returnmsg.data;
}
}
Contract Source Code
File 3 of 23: ERC165.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)pragmasolidity ^0.8.0;import"./IERC165.sol";
/**
* @dev Implementation of the {IERC165} interface.
*
* Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check
* for the additional interface id that will be supported. For example:
*
* ```solidity
* function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
* return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);
* }
* ```
*
* Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.
*/abstractcontractERC165isIERC165{
/**
* @dev See {IERC165-supportsInterface}.
*/functionsupportsInterface(bytes4 interfaceId) publicviewvirtualoverridereturns (bool) {
return interfaceId ==type(IERC165).interfaceId;
}
}
Contract Source Code
File 4 of 23: ERC20.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts (last updated v4.8.0) (token/ERC20/ERC20.sol)pragmasolidity ^0.8.0;import"./IERC20.sol";
import"./extensions/IERC20Metadata.sol";
import"../../utils/Context.sol";
/**
* @dev Implementation of the {IERC20} interface.
*
* This implementation is agnostic to the way tokens are created. This means
* that a supply mechanism has to be added in a derived contract using {_mint}.
* For a generic mechanism see {ERC20PresetMinterPauser}.
*
* TIP: For a detailed writeup see our guide
* https://forum.openzeppelin.com/t/how-to-implement-erc20-supply-mechanisms/226[How
* to implement supply mechanisms].
*
* We have followed general OpenZeppelin Contracts guidelines: functions revert
* instead returning `false` on failure. This behavior is nonetheless
* conventional and does not conflict with the expectations of ERC20
* applications.
*
* Additionally, an {Approval} event is emitted on calls to {transferFrom}.
* This allows applications to reconstruct the allowance for all accounts just
* by listening to said events. Other implementations of the EIP may not emit
* these events, as it isn't required by the specification.
*
* Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
* functions have been added to mitigate the well-known issues around setting
* allowances. See {IERC20-approve}.
*/contractERC20isContext, IERC20, IERC20Metadata{
mapping(address=>uint256) private _balances;
mapping(address=>mapping(address=>uint256)) private _allowances;
uint256private _totalSupply;
stringprivate _name;
stringprivate _symbol;
/**
* @dev Sets the values for {name} and {symbol}.
*
* The default value of {decimals} is 18. To select a different value for
* {decimals} you should overload it.
*
* All two of these values are immutable: they can only be set once during
* construction.
*/constructor(stringmemory name_, stringmemory symbol_) {
_name = name_;
_symbol = symbol_;
}
/**
* @dev Returns the name of the token.
*/functionname() publicviewvirtualoverridereturns (stringmemory) {
return _name;
}
/**
* @dev Returns the symbol of the token, usually a shorter version of the
* name.
*/functionsymbol() publicviewvirtualoverridereturns (stringmemory) {
return _symbol;
}
/**
* @dev Returns the number of decimals used to get its user representation.
* For example, if `decimals` equals `2`, a balance of `505` tokens should
* be displayed to a user as `5.05` (`505 / 10 ** 2`).
*
* Tokens usually opt for a value of 18, imitating the relationship between
* Ether and Wei. This is the value {ERC20} uses, unless this function is
* overridden;
*
* NOTE: This information is only used for _display_ purposes: it in
* no way affects any of the arithmetic of the contract, including
* {IERC20-balanceOf} and {IERC20-transfer}.
*/functiondecimals() publicviewvirtualoverridereturns (uint8) {
return18;
}
/**
* @dev See {IERC20-totalSupply}.
*/functiontotalSupply() publicviewvirtualoverridereturns (uint256) {
return _totalSupply;
}
/**
* @dev See {IERC20-balanceOf}.
*/functionbalanceOf(address account) publicviewvirtualoverridereturns (uint256) {
return _balances[account];
}
/**
* @dev See {IERC20-transfer}.
*
* Requirements:
*
* - `to` cannot be the zero address.
* - the caller must have a balance of at least `amount`.
*/functiontransfer(address to, uint256 amount) publicvirtualoverridereturns (bool) {
address owner = _msgSender();
_transfer(owner, to, amount);
returntrue;
}
/**
* @dev See {IERC20-allowance}.
*/functionallowance(address owner, address spender) publicviewvirtualoverridereturns (uint256) {
return _allowances[owner][spender];
}
/**
* @dev See {IERC20-approve}.
*
* NOTE: If `amount` is the maximum `uint256`, the allowance is not updated on
* `transferFrom`. This is semantically equivalent to an infinite approval.
*
* Requirements:
*
* - `spender` cannot be the zero address.
*/functionapprove(address spender, uint256 amount) publicvirtualoverridereturns (bool) {
address owner = _msgSender();
_approve(owner, spender, amount);
returntrue;
}
/**
* @dev See {IERC20-transferFrom}.
*
* Emits an {Approval} event indicating the updated allowance. This is not
* required by the EIP. See the note at the beginning of {ERC20}.
*
* NOTE: Does not update the allowance if the current allowance
* is the maximum `uint256`.
*
* Requirements:
*
* - `from` and `to` cannot be the zero address.
* - `from` must have a balance of at least `amount`.
* - the caller must have allowance for ``from``'s tokens of at least
* `amount`.
*/functiontransferFrom(addressfrom,
address to,
uint256 amount
) publicvirtualoverridereturns (bool) {
address spender = _msgSender();
_spendAllowance(from, spender, amount);
_transfer(from, to, amount);
returntrue;
}
/**
* @dev Atomically increases the allowance granted to `spender` by the caller.
*
* This is an alternative to {approve} that can be used as a mitigation for
* problems described in {IERC20-approve}.
*
* Emits an {Approval} event indicating the updated allowance.
*
* Requirements:
*
* - `spender` cannot be the zero address.
*/functionincreaseAllowance(address spender, uint256 addedValue) publicvirtualreturns (bool) {
address owner = _msgSender();
_approve(owner, spender, allowance(owner, spender) + addedValue);
returntrue;
}
/**
* @dev Atomically decreases the allowance granted to `spender` by the caller.
*
* This is an alternative to {approve} that can be used as a mitigation for
* problems described in {IERC20-approve}.
*
* Emits an {Approval} event indicating the updated allowance.
*
* Requirements:
*
* - `spender` cannot be the zero address.
* - `spender` must have allowance for the caller of at least
* `subtractedValue`.
*/functiondecreaseAllowance(address spender, uint256 subtractedValue) publicvirtualreturns (bool) {
address owner = _msgSender();
uint256 currentAllowance = allowance(owner, spender);
require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
unchecked {
_approve(owner, spender, currentAllowance - subtractedValue);
}
returntrue;
}
/**
* @dev Moves `amount` of tokens from `from` to `to`.
*
* This internal function is equivalent to {transfer}, and can be used to
* e.g. implement automatic token fees, slashing mechanisms, etc.
*
* Emits a {Transfer} event.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `from` must have a balance of at least `amount`.
*/function_transfer(addressfrom,
address to,
uint256 amount
) internalvirtual{
require(from!=address(0), "ERC20: transfer from the zero address");
require(to !=address(0), "ERC20: transfer to the zero address");
_beforeTokenTransfer(from, to, amount);
uint256 fromBalance = _balances[from];
require(fromBalance >= amount, "ERC20: transfer amount exceeds balance");
unchecked {
_balances[from] = fromBalance - amount;
// Overflow not possible: the sum of all balances is capped by totalSupply, and the sum is preserved by// decrementing then incrementing.
_balances[to] += amount;
}
emit Transfer(from, to, amount);
_afterTokenTransfer(from, to, amount);
}
/** @dev Creates `amount` tokens and assigns them to `account`, increasing
* the total supply.
*
* Emits a {Transfer} event with `from` set to the zero address.
*
* Requirements:
*
* - `account` cannot be the zero address.
*/function_mint(address account, uint256 amount) internalvirtual{
require(account !=address(0), "ERC20: mint to the zero address");
_beforeTokenTransfer(address(0), account, amount);
_totalSupply += amount;
unchecked {
// Overflow not possible: balance + amount is at most totalSupply + amount, which is checked above.
_balances[account] += amount;
}
emit Transfer(address(0), account, amount);
_afterTokenTransfer(address(0), account, amount);
}
/**
* @dev Destroys `amount` tokens from `account`, reducing the
* total supply.
*
* Emits a {Transfer} event with `to` set to the zero address.
*
* Requirements:
*
* - `account` cannot be the zero address.
* - `account` must have at least `amount` tokens.
*/function_burn(address account, uint256 amount) internalvirtual{
require(account !=address(0), "ERC20: burn from the zero address");
_beforeTokenTransfer(account, address(0), amount);
uint256 accountBalance = _balances[account];
require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
unchecked {
_balances[account] = accountBalance - amount;
// Overflow not possible: amount <= accountBalance <= totalSupply.
_totalSupply -= amount;
}
emit Transfer(account, address(0), amount);
_afterTokenTransfer(account, address(0), amount);
}
/**
* @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
*
* This internal function is equivalent to `approve`, and can be used to
* e.g. set automatic allowances for certain subsystems, etc.
*
* Emits an {Approval} event.
*
* Requirements:
*
* - `owner` cannot be the zero address.
* - `spender` cannot be the zero address.
*/function_approve(address owner,
address spender,
uint256 amount
) internalvirtual{
require(owner !=address(0), "ERC20: approve from the zero address");
require(spender !=address(0), "ERC20: approve to the zero address");
_allowances[owner][spender] = amount;
emit Approval(owner, spender, amount);
}
/**
* @dev Updates `owner` s allowance for `spender` based on spent `amount`.
*
* Does not update the allowance amount in case of infinite allowance.
* Revert if not enough allowance is available.
*
* Might emit an {Approval} event.
*/function_spendAllowance(address owner,
address spender,
uint256 amount
) internalvirtual{
uint256 currentAllowance = allowance(owner, spender);
if (currentAllowance !=type(uint256).max) {
require(currentAllowance >= amount, "ERC20: insufficient allowance");
unchecked {
_approve(owner, spender, currentAllowance - amount);
}
}
}
/**
* @dev Hook that is called before any transfer of tokens. This includes
* minting and burning.
*
* Calling conditions:
*
* - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
* will be transferred to `to`.
* - when `from` is zero, `amount` tokens will be minted for `to`.
* - when `to` is zero, `amount` of ``from``'s tokens will be burned.
* - `from` and `to` are never both zero.
*
* To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
*/function_beforeTokenTransfer(addressfrom,
address to,
uint256 amount
) internalvirtual{}
/**
* @dev Hook that is called after any transfer of tokens. This includes
* minting and burning.
*
* Calling conditions:
*
* - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
* has been transferred to `to`.
* - when `from` is zero, `amount` tokens have been minted for `to`.
* - when `to` is zero, `amount` of ``from``'s tokens have been burned.
* - `from` and `to` are never both zero.
*
* To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
*/function_afterTokenTransfer(addressfrom,
address to,
uint256 amount
) internalvirtual{}
}
Contract Source Code
File 5 of 23: ERC721.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts (last updated v4.8.2) (token/ERC721/ERC721.sol)pragmasolidity ^0.8.0;import"./IERC721.sol";
import"./IERC721Receiver.sol";
import"./extensions/IERC721Metadata.sol";
import"../../utils/Address.sol";
import"../../utils/Context.sol";
import"../../utils/Strings.sol";
import"../../utils/introspection/ERC165.sol";
/**
* @dev Implementation of https://eips.ethereum.org/EIPS/eip-721[ERC721] Non-Fungible Token Standard, including
* the Metadata extension, but not including the Enumerable extension, which is available separately as
* {ERC721Enumerable}.
*/contractERC721isContext, ERC165, IERC721, IERC721Metadata{
usingAddressforaddress;
usingStringsforuint256;
// Token namestringprivate _name;
// Token symbolstringprivate _symbol;
// Mapping from token ID to owner addressmapping(uint256=>address) private _owners;
// Mapping owner address to token countmapping(address=>uint256) private _balances;
// Mapping from token ID to approved addressmapping(uint256=>address) private _tokenApprovals;
// Mapping from owner to operator approvalsmapping(address=>mapping(address=>bool)) private _operatorApprovals;
/**
* @dev Initializes the contract by setting a `name` and a `symbol` to the token collection.
*/constructor(stringmemory name_, stringmemory symbol_) {
_name = name_;
_symbol = symbol_;
}
/**
* @dev See {IERC165-supportsInterface}.
*/functionsupportsInterface(bytes4 interfaceId) publicviewvirtualoverride(ERC165, IERC165) returns (bool) {
return
interfaceId ==type(IERC721).interfaceId||
interfaceId ==type(IERC721Metadata).interfaceId||super.supportsInterface(interfaceId);
}
/**
* @dev See {IERC721-balanceOf}.
*/functionbalanceOf(address owner) publicviewvirtualoverridereturns (uint256) {
require(owner !=address(0), "ERC721: address zero is not a valid owner");
return _balances[owner];
}
/**
* @dev See {IERC721-ownerOf}.
*/functionownerOf(uint256 tokenId) publicviewvirtualoverridereturns (address) {
address owner = _ownerOf(tokenId);
require(owner !=address(0), "ERC721: invalid token ID");
return owner;
}
/**
* @dev See {IERC721Metadata-name}.
*/functionname() publicviewvirtualoverridereturns (stringmemory) {
return _name;
}
/**
* @dev See {IERC721Metadata-symbol}.
*/functionsymbol() publicviewvirtualoverridereturns (stringmemory) {
return _symbol;
}
/**
* @dev See {IERC721Metadata-tokenURI}.
*/functiontokenURI(uint256 tokenId) publicviewvirtualoverridereturns (stringmemory) {
_requireMinted(tokenId);
stringmemory baseURI = _baseURI();
returnbytes(baseURI).length>0 ? string(abi.encodePacked(baseURI, tokenId.toString())) : "";
}
/**
* @dev Base URI for computing {tokenURI}. If set, the resulting URI for each
* token will be the concatenation of the `baseURI` and the `tokenId`. Empty
* by default, can be overridden in child contracts.
*/function_baseURI() internalviewvirtualreturns (stringmemory) {
return"";
}
/**
* @dev See {IERC721-approve}.
*/functionapprove(address to, uint256 tokenId) publicvirtualoverride{
address owner = ERC721.ownerOf(tokenId);
require(to != owner, "ERC721: approval to current owner");
require(
_msgSender() == owner || isApprovedForAll(owner, _msgSender()),
"ERC721: approve caller is not token owner or approved for all"
);
_approve(to, tokenId);
}
/**
* @dev See {IERC721-getApproved}.
*/functiongetApproved(uint256 tokenId) publicviewvirtualoverridereturns (address) {
_requireMinted(tokenId);
return _tokenApprovals[tokenId];
}
/**
* @dev See {IERC721-setApprovalForAll}.
*/functionsetApprovalForAll(address operator, bool approved) publicvirtualoverride{
_setApprovalForAll(_msgSender(), operator, approved);
}
/**
* @dev See {IERC721-isApprovedForAll}.
*/functionisApprovedForAll(address owner, address operator) publicviewvirtualoverridereturns (bool) {
return _operatorApprovals[owner][operator];
}
/**
* @dev See {IERC721-transferFrom}.
*/functiontransferFrom(addressfrom,
address to,
uint256 tokenId
) publicvirtualoverride{
//solhint-disable-next-line max-line-lengthrequire(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: caller is not token owner or approved");
_transfer(from, to, tokenId);
}
/**
* @dev See {IERC721-safeTransferFrom}.
*/functionsafeTransferFrom(addressfrom,
address to,
uint256 tokenId
) publicvirtualoverride{
safeTransferFrom(from, to, tokenId, "");
}
/**
* @dev See {IERC721-safeTransferFrom}.
*/functionsafeTransferFrom(addressfrom,
address to,
uint256 tokenId,
bytesmemory data
) publicvirtualoverride{
require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: caller is not token owner or approved");
_safeTransfer(from, to, tokenId, data);
}
/**
* @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.
*
* `data` is additional data, it has no specified format and it is sent in call to `to`.
*
* This internal function is equivalent to {safeTransferFrom}, and can be used to e.g.
* implement alternative mechanisms to perform token transfer, such as signature-based.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must exist and be owned by `from`.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
*
* Emits a {Transfer} event.
*/function_safeTransfer(addressfrom,
address to,
uint256 tokenId,
bytesmemory data
) internalvirtual{
_transfer(from, to, tokenId);
require(_checkOnERC721Received(from, to, tokenId, data), "ERC721: transfer to non ERC721Receiver implementer");
}
/**
* @dev Returns the owner of the `tokenId`. Does NOT revert if token doesn't exist
*/function_ownerOf(uint256 tokenId) internalviewvirtualreturns (address) {
return _owners[tokenId];
}
/**
* @dev Returns whether `tokenId` exists.
*
* Tokens can be managed by their owner or approved accounts via {approve} or {setApprovalForAll}.
*
* Tokens start existing when they are minted (`_mint`),
* and stop existing when they are burned (`_burn`).
*/function_exists(uint256 tokenId) internalviewvirtualreturns (bool) {
return _ownerOf(tokenId) !=address(0);
}
/**
* @dev Returns whether `spender` is allowed to manage `tokenId`.
*
* Requirements:
*
* - `tokenId` must exist.
*/function_isApprovedOrOwner(address spender, uint256 tokenId) internalviewvirtualreturns (bool) {
address owner = ERC721.ownerOf(tokenId);
return (spender == owner || isApprovedForAll(owner, spender) || getApproved(tokenId) == spender);
}
/**
* @dev Safely mints `tokenId` and transfers it to `to`.
*
* Requirements:
*
* - `tokenId` must not exist.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
*
* Emits a {Transfer} event.
*/function_safeMint(address to, uint256 tokenId) internalvirtual{
_safeMint(to, tokenId, "");
}
/**
* @dev Same as {xref-ERC721-_safeMint-address-uint256-}[`_safeMint`], with an additional `data` parameter which is
* forwarded in {IERC721Receiver-onERC721Received} to contract recipients.
*/function_safeMint(address to,
uint256 tokenId,
bytesmemory data
) internalvirtual{
_mint(to, tokenId);
require(
_checkOnERC721Received(address(0), to, tokenId, data),
"ERC721: transfer to non ERC721Receiver implementer"
);
}
/**
* @dev Mints `tokenId` and transfers it to `to`.
*
* WARNING: Usage of this method is discouraged, use {_safeMint} whenever possible
*
* Requirements:
*
* - `tokenId` must not exist.
* - `to` cannot be the zero address.
*
* Emits a {Transfer} event.
*/function_mint(address to, uint256 tokenId) internalvirtual{
require(to !=address(0), "ERC721: mint to the zero address");
require(!_exists(tokenId), "ERC721: token already minted");
_beforeTokenTransfer(address(0), to, tokenId, 1);
// Check that tokenId was not minted by `_beforeTokenTransfer` hookrequire(!_exists(tokenId), "ERC721: token already minted");
unchecked {
// Will not overflow unless all 2**256 token ids are minted to the same owner.// Given that tokens are minted one by one, it is impossible in practice that// this ever happens. Might change if we allow batch minting.// The ERC fails to describe this case.
_balances[to] +=1;
}
_owners[tokenId] = to;
emit Transfer(address(0), to, tokenId);
_afterTokenTransfer(address(0), to, tokenId, 1);
}
/**
* @dev Destroys `tokenId`.
* The approval is cleared when the token is burned.
* This is an internal function that does not check if the sender is authorized to operate on the token.
*
* Requirements:
*
* - `tokenId` must exist.
*
* Emits a {Transfer} event.
*/function_burn(uint256 tokenId) internalvirtual{
address owner = ERC721.ownerOf(tokenId);
_beforeTokenTransfer(owner, address(0), tokenId, 1);
// Update ownership in case tokenId was transferred by `_beforeTokenTransfer` hook
owner = ERC721.ownerOf(tokenId);
// Clear approvalsdelete _tokenApprovals[tokenId];
unchecked {
// Cannot overflow, as that would require more tokens to be burned/transferred// out than the owner initially received through minting and transferring in.
_balances[owner] -=1;
}
delete _owners[tokenId];
emit Transfer(owner, address(0), tokenId);
_afterTokenTransfer(owner, address(0), tokenId, 1);
}
/**
* @dev Transfers `tokenId` from `from` to `to`.
* As opposed to {transferFrom}, this imposes no restrictions on msg.sender.
*
* Requirements:
*
* - `to` cannot be the zero address.
* - `tokenId` token must be owned by `from`.
*
* Emits a {Transfer} event.
*/function_transfer(addressfrom,
address to,
uint256 tokenId
) internalvirtual{
require(ERC721.ownerOf(tokenId) ==from, "ERC721: transfer from incorrect owner");
require(to !=address(0), "ERC721: transfer to the zero address");
_beforeTokenTransfer(from, to, tokenId, 1);
// Check that tokenId was not transferred by `_beforeTokenTransfer` hookrequire(ERC721.ownerOf(tokenId) ==from, "ERC721: transfer from incorrect owner");
// Clear approvals from the previous ownerdelete _tokenApprovals[tokenId];
unchecked {
// `_balances[from]` cannot overflow for the same reason as described in `_burn`:// `from`'s balance is the number of token held, which is at least one before the current// transfer.// `_balances[to]` could overflow in the conditions described in `_mint`. That would require// all 2**256 token ids to be minted, which in practice is impossible.
_balances[from] -=1;
_balances[to] +=1;
}
_owners[tokenId] = to;
emit Transfer(from, to, tokenId);
_afterTokenTransfer(from, to, tokenId, 1);
}
/**
* @dev Approve `to` to operate on `tokenId`
*
* Emits an {Approval} event.
*/function_approve(address to, uint256 tokenId) internalvirtual{
_tokenApprovals[tokenId] = to;
emit Approval(ERC721.ownerOf(tokenId), to, tokenId);
}
/**
* @dev Approve `operator` to operate on all of `owner` tokens
*
* Emits an {ApprovalForAll} event.
*/function_setApprovalForAll(address owner,
address operator,
bool approved
) internalvirtual{
require(owner != operator, "ERC721: approve to caller");
_operatorApprovals[owner][operator] = approved;
emit ApprovalForAll(owner, operator, approved);
}
/**
* @dev Reverts if the `tokenId` has not been minted yet.
*/function_requireMinted(uint256 tokenId) internalviewvirtual{
require(_exists(tokenId), "ERC721: invalid token ID");
}
/**
* @dev Internal function to invoke {IERC721Receiver-onERC721Received} on a target address.
* The call is not executed if the target address is not a contract.
*
* @param from address representing the previous owner of the given token ID
* @param to target address that will receive the tokens
* @param tokenId uint256 ID of the token to be transferred
* @param data bytes optional data to send along with the call
* @return bool whether the call correctly returned the expected magic value
*/function_checkOnERC721Received(addressfrom,
address to,
uint256 tokenId,
bytesmemory data
) privatereturns (bool) {
if (to.isContract()) {
try IERC721Receiver(to).onERC721Received(_msgSender(), from, tokenId, data) returns (bytes4 retval) {
return retval == IERC721Receiver.onERC721Received.selector;
} catch (bytesmemory reason) {
if (reason.length==0) {
revert("ERC721: transfer to non ERC721Receiver implementer");
} else {
/// @solidity memory-safe-assemblyassembly {
revert(add(32, reason), mload(reason))
}
}
}
} else {
returntrue;
}
}
/**
* @dev Hook that is called before any token transfer. This includes minting and burning. If {ERC721Consecutive} is
* used, the hook may be called as part of a consecutive (batch) mint, as indicated by `batchSize` greater than 1.
*
* Calling conditions:
*
* - When `from` and `to` are both non-zero, ``from``'s tokens will be transferred to `to`.
* - When `from` is zero, the tokens will be minted for `to`.
* - When `to` is zero, ``from``'s tokens will be burned.
* - `from` and `to` are never both zero.
* - `batchSize` is non-zero.
*
* To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
*/function_beforeTokenTransfer(addressfrom,
address to,
uint256 firstTokenId,
uint256 batchSize
) internalvirtual{}
/**
* @dev Hook that is called after any token transfer. This includes minting and burning. If {ERC721Consecutive} is
* used, the hook may be called as part of a consecutive (batch) mint, as indicated by `batchSize` greater than 1.
*
* Calling conditions:
*
* - When `from` and `to` are both non-zero, ``from``'s tokens were transferred to `to`.
* - When `from` is zero, the tokens were minted for `to`.
* - When `to` is zero, ``from``'s tokens were burned.
* - `from` and `to` are never both zero.
* - `batchSize` is non-zero.
*
* To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
*/function_afterTokenTransfer(addressfrom,
address to,
uint256 firstTokenId,
uint256 batchSize
) internalvirtual{}
/**
* @dev Unsafe write access to the balances, used by extensions that "mint" tokens using an {ownerOf} override.
*
* WARNING: Anyone calling this MUST ensure that the balances remain consistent with the ownership. The invariant
* being that for any address `a` the value returned by `balanceOf(a)` must be equal to the number of tokens such
* that `ownerOf(tokenId)` is `a`.
*/// solhint-disable-next-line func-name-mixedcasefunction__unsafe_increaseBalance(address account, uint256 amount) internal{
_balances[account] += amount;
}
}
Contract Source Code
File 6 of 23: ERC721Enumerable.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts (last updated v4.8.0) (token/ERC721/extensions/ERC721Enumerable.sol)pragmasolidity ^0.8.0;import"../ERC721.sol";
import"./IERC721Enumerable.sol";
/**
* @dev This implements an optional extension of {ERC721} defined in the EIP that adds
* enumerability of all the token ids in the contract as well as all token ids owned by each
* account.
*/abstractcontractERC721EnumerableisERC721, IERC721Enumerable{
// Mapping from owner to list of owned token IDsmapping(address=>mapping(uint256=>uint256)) private _ownedTokens;
// Mapping from token ID to index of the owner tokens listmapping(uint256=>uint256) private _ownedTokensIndex;
// Array with all token ids, used for enumerationuint256[] private _allTokens;
// Mapping from token id to position in the allTokens arraymapping(uint256=>uint256) private _allTokensIndex;
/**
* @dev See {IERC165-supportsInterface}.
*/functionsupportsInterface(bytes4 interfaceId) publicviewvirtualoverride(IERC165, ERC721) returns (bool) {
return interfaceId ==type(IERC721Enumerable).interfaceId||super.supportsInterface(interfaceId);
}
/**
* @dev See {IERC721Enumerable-tokenOfOwnerByIndex}.
*/functiontokenOfOwnerByIndex(address owner, uint256 index) publicviewvirtualoverridereturns (uint256) {
require(index < ERC721.balanceOf(owner), "ERC721Enumerable: owner index out of bounds");
return _ownedTokens[owner][index];
}
/**
* @dev See {IERC721Enumerable-totalSupply}.
*/functiontotalSupply() publicviewvirtualoverridereturns (uint256) {
return _allTokens.length;
}
/**
* @dev See {IERC721Enumerable-tokenByIndex}.
*/functiontokenByIndex(uint256 index) publicviewvirtualoverridereturns (uint256) {
require(index < ERC721Enumerable.totalSupply(), "ERC721Enumerable: global index out of bounds");
return _allTokens[index];
}
/**
* @dev See {ERC721-_beforeTokenTransfer}.
*/function_beforeTokenTransfer(addressfrom,
address to,
uint256 firstTokenId,
uint256 batchSize
) internalvirtualoverride{
super._beforeTokenTransfer(from, to, firstTokenId, batchSize);
if (batchSize >1) {
// Will only trigger during construction. Batch transferring (minting) is not available afterwards.revert("ERC721Enumerable: consecutive transfers not supported");
}
uint256 tokenId = firstTokenId;
if (from==address(0)) {
_addTokenToAllTokensEnumeration(tokenId);
} elseif (from!= to) {
_removeTokenFromOwnerEnumeration(from, tokenId);
}
if (to ==address(0)) {
_removeTokenFromAllTokensEnumeration(tokenId);
} elseif (to !=from) {
_addTokenToOwnerEnumeration(to, tokenId);
}
}
/**
* @dev Private function to add a token to this extension's ownership-tracking data structures.
* @param to address representing the new owner of the given token ID
* @param tokenId uint256 ID of the token to be added to the tokens list of the given address
*/function_addTokenToOwnerEnumeration(address to, uint256 tokenId) private{
uint256 length = ERC721.balanceOf(to);
_ownedTokens[to][length] = tokenId;
_ownedTokensIndex[tokenId] = length;
}
/**
* @dev Private function to add a token to this extension's token tracking data structures.
* @param tokenId uint256 ID of the token to be added to the tokens list
*/function_addTokenToAllTokensEnumeration(uint256 tokenId) private{
_allTokensIndex[tokenId] = _allTokens.length;
_allTokens.push(tokenId);
}
/**
* @dev Private function to remove a token from this extension's ownership-tracking data structures. Note that
* while the token is not assigned a new owner, the `_ownedTokensIndex` mapping is _not_ updated: this allows for
* gas optimizations e.g. when performing a transfer operation (avoiding double writes).
* This has O(1) time complexity, but alters the order of the _ownedTokens array.
* @param from address representing the previous owner of the given token ID
* @param tokenId uint256 ID of the token to be removed from the tokens list of the given address
*/function_removeTokenFromOwnerEnumeration(addressfrom, uint256 tokenId) private{
// To prevent a gap in from's tokens array, we store the last token in the index of the token to delete, and// then delete the last slot (swap and pop).uint256 lastTokenIndex = ERC721.balanceOf(from) -1;
uint256 tokenIndex = _ownedTokensIndex[tokenId];
// When the token to delete is the last token, the swap operation is unnecessaryif (tokenIndex != lastTokenIndex) {
uint256 lastTokenId = _ownedTokens[from][lastTokenIndex];
_ownedTokens[from][tokenIndex] = lastTokenId; // Move the last token to the slot of the to-delete token
_ownedTokensIndex[lastTokenId] = tokenIndex; // Update the moved token's index
}
// This also deletes the contents at the last position of the arraydelete _ownedTokensIndex[tokenId];
delete _ownedTokens[from][lastTokenIndex];
}
/**
* @dev Private function to remove a token from this extension's token tracking data structures.
* This has O(1) time complexity, but alters the order of the _allTokens array.
* @param tokenId uint256 ID of the token to be removed from the tokens list
*/function_removeTokenFromAllTokensEnumeration(uint256 tokenId) private{
// To prevent a gap in the tokens array, we store the last token in the index of the token to delete, and// then delete the last slot (swap and pop).uint256 lastTokenIndex = _allTokens.length-1;
uint256 tokenIndex = _allTokensIndex[tokenId];
// When the token to delete is the last token, the swap operation is unnecessary. However, since this occurs so// rarely (when the last minted token is burnt) that we still do the swap here to avoid the gas cost of adding// an 'if' statement (like in _removeTokenFromOwnerEnumeration)uint256 lastTokenId = _allTokens[lastTokenIndex];
_allTokens[tokenIndex] = lastTokenId; // Move the last token to the slot of the to-delete token
_allTokensIndex[lastTokenId] = tokenIndex; // Update the moved token's index// This also deletes the contents at the last position of the arraydelete _allTokensIndex[tokenId];
_allTokens.pop();
}
}
Contract Source Code
File 7 of 23: IERC165.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)pragmasolidity ^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}.
*/interfaceIERC165{
/**
* @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.
*/functionsupportsInterface(bytes4 interfaceId) externalviewreturns (bool);
}
Contract Source Code
File 8 of 23: IERC20.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol)pragmasolidity ^0.8.0;/**
* @dev Interface of the ERC20 standard as defined in the EIP.
*/interfaceIERC20{
/**
* @dev Emitted when `value` tokens are moved from one account (`from`) to
* another (`to`).
*
* Note that `value` may be zero.
*/eventTransfer(addressindexedfrom, addressindexed 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.
*/eventApproval(addressindexed owner, addressindexed spender, uint256 value);
/**
* @dev Returns the amount of tokens in existence.
*/functiontotalSupply() externalviewreturns (uint256);
/**
* @dev Returns the amount of tokens owned by `account`.
*/functionbalanceOf(address account) externalviewreturns (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.
*/functiontransfer(address to, uint256 amount) externalreturns (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.
*/functionallowance(address owner, address spender) externalviewreturns (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.
*/functionapprove(address spender, uint256 amount) externalreturns (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.
*/functiontransferFrom(addressfrom,
address to,
uint256 amount
) externalreturns (bool);
}
Contract Source Code
File 9 of 23: IERC20Metadata.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol)pragmasolidity ^0.8.0;import"../IERC20.sol";
/**
* @dev Interface for the optional metadata functions from the ERC20 standard.
*
* _Available since v4.1._
*/interfaceIERC20MetadataisIERC20{
/**
* @dev Returns the name of the token.
*/functionname() externalviewreturns (stringmemory);
/**
* @dev Returns the symbol of the token.
*/functionsymbol() externalviewreturns (stringmemory);
/**
* @dev Returns the decimals places of the token.
*/functiondecimals() externalviewreturns (uint8);
}
Contract Source Code
File 10 of 23: IERC721.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts (last updated v4.8.0) (token/ERC721/IERC721.sol)pragmasolidity ^0.8.0;import"../../utils/introspection/IERC165.sol";
/**
* @dev Required interface of an ERC721 compliant contract.
*/interfaceIERC721isIERC165{
/**
* @dev Emitted when `tokenId` token is transferred from `from` to `to`.
*/eventTransfer(addressindexedfrom, addressindexed to, uint256indexed tokenId);
/**
* @dev Emitted when `owner` enables `approved` to manage the `tokenId` token.
*/eventApproval(addressindexed owner, addressindexed approved, uint256indexed tokenId);
/**
* @dev Emitted when `owner` enables or disables (`approved`) `operator` to manage all of its assets.
*/eventApprovalForAll(addressindexed owner, addressindexed operator, bool approved);
/**
* @dev Returns the number of tokens in ``owner``'s account.
*/functionbalanceOf(address owner) externalviewreturns (uint256 balance);
/**
* @dev Returns the owner of the `tokenId` token.
*
* Requirements:
*
* - `tokenId` must exist.
*/functionownerOf(uint256 tokenId) externalviewreturns (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.
*/functionsafeTransferFrom(addressfrom,
address to,
uint256 tokenId,
bytescalldata 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.
*/functionsafeTransferFrom(addressfrom,
address to,
uint256 tokenId
) external;
/**
* @dev Transfers `tokenId` token from `from` to `to`.
*
* WARNING: Note that the caller is responsible to confirm that the recipient is capable of receiving ERC721
* or else they may be permanently lost. Usage of {safeTransferFrom} prevents loss, though the caller must
* understand this adds an external call which potentially creates a reentrancy vulnerability.
*
* 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.
*/functiontransferFrom(addressfrom,
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.
*/functionapprove(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.
*/functionsetApprovalForAll(address operator, bool _approved) external;
/**
* @dev Returns the account approved for `tokenId` token.
*
* Requirements:
*
* - `tokenId` must exist.
*/functiongetApproved(uint256 tokenId) externalviewreturns (address operator);
/**
* @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.
*
* See {setApprovalForAll}
*/functionisApprovedForAll(address owner, address operator) externalviewreturns (bool);
}
Contract Source Code
File 11 of 23: IERC721Enumerable.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts (last updated v4.5.0) (token/ERC721/extensions/IERC721Enumerable.sol)pragmasolidity ^0.8.0;import"../IERC721.sol";
/**
* @title ERC-721 Non-Fungible Token Standard, optional enumeration extension
* @dev See https://eips.ethereum.org/EIPS/eip-721
*/interfaceIERC721EnumerableisIERC721{
/**
* @dev Returns the total amount of tokens stored by the contract.
*/functiontotalSupply() externalviewreturns (uint256);
/**
* @dev Returns a token ID owned by `owner` at a given `index` of its token list.
* Use along with {balanceOf} to enumerate all of ``owner``'s tokens.
*/functiontokenOfOwnerByIndex(address owner, uint256 index) externalviewreturns (uint256);
/**
* @dev Returns a token ID at a given `index` of all the tokens stored by the contract.
* Use along with {totalSupply} to enumerate all tokens.
*/functiontokenByIndex(uint256 index) externalviewreturns (uint256);
}
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC721/IERC721Receiver.sol)pragmasolidity ^0.8.0;/**
* @title ERC721 token receiver interface
* @dev Interface for any contract that wants to support safeTransfers
* from ERC721 asset contracts.
*/interfaceIERC721Receiver{
/**
* @dev Whenever an {IERC721} `tokenId` token is transferred to this contract via {IERC721-safeTransferFrom}
* by `operator` from `from`, this function is called.
*
* It must return its Solidity selector to confirm the token transfer.
* If any other value is returned or the interface is not implemented by the recipient, the transfer will be reverted.
*
* The selector can be obtained in Solidity with `IERC721Receiver.onERC721Received.selector`.
*/functiononERC721Received(address operator,
addressfrom,
uint256 tokenId,
bytescalldata data
) externalreturns (bytes4);
}
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts (last updated v4.8.0) (utils/math/Math.sol)pragmasolidity ^0.8.0;/**
* @dev Standard math utilities missing in the Solidity language.
*/libraryMath{
enumRounding {
Down, // Toward negative infinity
Up, // Toward infinity
Zero // Toward zero
}
/**
* @dev Returns the largest of two numbers.
*/functionmax(uint256 a, uint256 b) internalpurereturns (uint256) {
return a > b ? a : b;
}
/**
* @dev Returns the smallest of two numbers.
*/functionmin(uint256 a, uint256 b) internalpurereturns (uint256) {
return a < b ? a : b;
}
/**
* @dev Returns the average of two numbers. The result is rounded towards
* zero.
*/functionaverage(uint256 a, uint256 b) internalpurereturns (uint256) {
// (a + b) / 2 can overflow.return (a & b) + (a ^ b) /2;
}
/**
* @dev Returns the ceiling of the division of two numbers.
*
* This differs from standard division with `/` in that it rounds up instead
* of rounding down.
*/functionceilDiv(uint256 a, uint256 b) internalpurereturns (uint256) {
// (a + b - 1) / b can overflow on addition, so we distribute.return a ==0 ? 0 : (a -1) / b +1;
}
/**
* @notice Calculates floor(x * y / denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
* @dev Original credit to Remco Bloemen under MIT license (https://xn--2-umb.com/21/muldiv)
* with further edits by Uniswap Labs also under MIT license.
*/functionmulDiv(uint256 x,
uint256 y,
uint256 denominator
) internalpurereturns (uint256 result) {
unchecked {
// 512-bit multiply [prod1 prod0] = x * y. Compute the product mod 2^256 and mod 2^256 - 1, then use// use the Chinese Remainder Theorem to reconstruct the 512 bit result. The result is stored in two 256// variables such that product = prod1 * 2^256 + prod0.uint256 prod0; // Least significant 256 bits of the productuint256 prod1; // Most significant 256 bits of the productassembly {
let mm :=mulmod(x, y, not(0))
prod0 :=mul(x, y)
prod1 :=sub(sub(mm, prod0), lt(mm, prod0))
}
// Handle non-overflow cases, 256 by 256 division.if (prod1 ==0) {
return prod0 / denominator;
}
// Make sure the result is less than 2^256. Also prevents denominator == 0.require(denominator > prod1);
///////////////////////////////////////////////// 512 by 256 division.///////////////////////////////////////////////// Make division exact by subtracting the remainder from [prod1 prod0].uint256 remainder;
assembly {
// Compute remainder using mulmod.
remainder :=mulmod(x, y, denominator)
// Subtract 256 bit number from 512 bit number.
prod1 :=sub(prod1, gt(remainder, prod0))
prod0 :=sub(prod0, remainder)
}
// Factor powers of two out of denominator and compute largest power of two divisor of denominator. Always >= 1.// See https://cs.stackexchange.com/q/138556/92363.// Does not overflow because the denominator cannot be zero at this stage in the function.uint256 twos = denominator & (~denominator +1);
assembly {
// Divide denominator by twos.
denominator :=div(denominator, twos)
// Divide [prod1 prod0] by twos.
prod0 :=div(prod0, twos)
// Flip twos such that it is 2^256 / twos. If twos is zero, then it becomes one.
twos :=add(div(sub(0, twos), twos), 1)
}
// Shift in bits from prod1 into prod0.
prod0 |= prod1 * twos;
// Invert denominator mod 2^256. Now that denominator is an odd number, it has an inverse modulo 2^256 such// that denominator * inv = 1 mod 2^256. Compute the inverse by starting with a seed that is correct for// four bits. That is, denominator * inv = 1 mod 2^4.uint256 inverse = (3* denominator) ^2;
// Use the Newton-Raphson iteration to improve the precision. Thanks to Hensel's lifting lemma, this also works// in modular arithmetic, doubling the correct bits in each step.
inverse *=2- denominator * inverse; // inverse mod 2^8
inverse *=2- denominator * inverse; // inverse mod 2^16
inverse *=2- denominator * inverse; // inverse mod 2^32
inverse *=2- denominator * inverse; // inverse mod 2^64
inverse *=2- denominator * inverse; // inverse mod 2^128
inverse *=2- denominator * inverse; // inverse mod 2^256// Because the division is now exact we can divide by multiplying with the modular inverse of denominator.// This will give us the correct result modulo 2^256. Since the preconditions guarantee that the outcome is// less than 2^256, this is the final result. We don't need to compute the high bits of the result and prod1// is no longer required.
result = prod0 * inverse;
return result;
}
}
/**
* @notice Calculates x * y / denominator with full precision, following the selected rounding direction.
*/functionmulDiv(uint256 x,
uint256 y,
uint256 denominator,
Rounding rounding
) internalpurereturns (uint256) {
uint256 result = mulDiv(x, y, denominator);
if (rounding == Rounding.Up &&mulmod(x, y, denominator) >0) {
result +=1;
}
return result;
}
/**
* @dev Returns the square root of a number. If the number is not a perfect square, the value is rounded down.
*
* Inspired by Henry S. Warren, Jr.'s "Hacker's Delight" (Chapter 11).
*/functionsqrt(uint256 a) internalpurereturns (uint256) {
if (a ==0) {
return0;
}
// For our first guess, we get the biggest power of 2 which is smaller than the square root of the target.//// We know that the "msb" (most significant bit) of our target number `a` is a power of 2 such that we have// `msb(a) <= a < 2*msb(a)`. This value can be written `msb(a)=2**k` with `k=log2(a)`.//// This can be rewritten `2**log2(a) <= a < 2**(log2(a) + 1)`// → `sqrt(2**k) <= sqrt(a) < sqrt(2**(k+1))`// → `2**(k/2) <= sqrt(a) < 2**((k+1)/2) <= 2**(k/2 + 1)`//// Consequently, `2**(log2(a) / 2)` is a good first approximation of `sqrt(a)` with at least 1 correct bit.uint256 result =1<< (log2(a) >>1);
// At this point `result` is an estimation with one bit of precision. We know the true value is a uint128,// since it is the square root of a uint256. Newton's method converges quadratically (precision doubles at// every iteration). We thus need at most 7 iteration to turn our partial result with one bit of precision// into the expected uint128 result.unchecked {
result = (result + a / result) >>1;
result = (result + a / result) >>1;
result = (result + a / result) >>1;
result = (result + a / result) >>1;
result = (result + a / result) >>1;
result = (result + a / result) >>1;
result = (result + a / result) >>1;
return min(result, a / result);
}
}
/**
* @notice Calculates sqrt(a), following the selected rounding direction.
*/functionsqrt(uint256 a, Rounding rounding) internalpurereturns (uint256) {
unchecked {
uint256 result = sqrt(a);
return result + (rounding == Rounding.Up && result * result < a ? 1 : 0);
}
}
/**
* @dev Return the log in base 2, rounded down, of a positive value.
* Returns 0 if given 0.
*/functionlog2(uint256 value) internalpurereturns (uint256) {
uint256 result =0;
unchecked {
if (value >>128>0) {
value >>=128;
result +=128;
}
if (value >>64>0) {
value >>=64;
result +=64;
}
if (value >>32>0) {
value >>=32;
result +=32;
}
if (value >>16>0) {
value >>=16;
result +=16;
}
if (value >>8>0) {
value >>=8;
result +=8;
}
if (value >>4>0) {
value >>=4;
result +=4;
}
if (value >>2>0) {
value >>=2;
result +=2;
}
if (value >>1>0) {
result +=1;
}
}
return result;
}
/**
* @dev Return the log in base 2, following the selected rounding direction, of a positive value.
* Returns 0 if given 0.
*/functionlog2(uint256 value, Rounding rounding) internalpurereturns (uint256) {
unchecked {
uint256 result =log2(value);
return result + (rounding == Rounding.Up &&1<< result < value ? 1 : 0);
}
}
/**
* @dev Return the log in base 10, rounded down, of a positive value.
* Returns 0 if given 0.
*/functionlog10(uint256 value) internalpurereturns (uint256) {
uint256 result =0;
unchecked {
if (value >=10**64) {
value /=10**64;
result +=64;
}
if (value >=10**32) {
value /=10**32;
result +=32;
}
if (value >=10**16) {
value /=10**16;
result +=16;
}
if (value >=10**8) {
value /=10**8;
result +=8;
}
if (value >=10**4) {
value /=10**4;
result +=4;
}
if (value >=10**2) {
value /=10**2;
result +=2;
}
if (value >=10**1) {
result +=1;
}
}
return result;
}
/**
* @dev Return the log in base 10, following the selected rounding direction, of a positive value.
* Returns 0 if given 0.
*/functionlog10(uint256 value, Rounding rounding) internalpurereturns (uint256) {
unchecked {
uint256 result = log10(value);
return result + (rounding == Rounding.Up &&10**result < value ? 1 : 0);
}
}
/**
* @dev Return the log in base 256, rounded down, of a positive value.
* Returns 0 if given 0.
*
* Adding one to the result gives the number of pairs of hex symbols needed to represent `value` as a hex string.
*/functionlog256(uint256 value) internalpurereturns (uint256) {
uint256 result =0;
unchecked {
if (value >>128>0) {
value >>=128;
result +=16;
}
if (value >>64>0) {
value >>=64;
result +=8;
}
if (value >>32>0) {
value >>=32;
result +=4;
}
if (value >>16>0) {
value >>=16;
result +=2;
}
if (value >>8>0) {
result +=1;
}
}
return result;
}
/**
* @dev Return the log in base 10, following the selected rounding direction, of a positive value.
* Returns 0 if given 0.
*/functionlog256(uint256 value, Rounding rounding) internalpurereturns (uint256) {
unchecked {
uint256 result = log256(value);
return result + (rounding == Rounding.Up &&1<< (result *8) < value ? 1 : 0);
}
}
}
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)pragmasolidity ^0.8.0;import"../utils/Context.sol";
/**
* @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.
*/abstractcontractOwnableisContext{
addressprivate _owner;
eventOwnershipTransferred(addressindexed previousOwner, addressindexed 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.
*/modifieronlyOwner() {
_checkOwner();
_;
}
/**
* @dev Returns the address of the current owner.
*/functionowner() publicviewvirtualreturns (address) {
return _owner;
}
/**
* @dev Throws if the sender is not the owner.
*/function_checkOwner() internalviewvirtual{
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.
*/functionrenounceOwnership() publicvirtualonlyOwner{
_transferOwnership(address(0));
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Can only be called by the current owner.
*/functiontransferOwnership(address newOwner) publicvirtualonlyOwner{
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) internalvirtual{
address oldOwner = _owner;
_owner = newOwner;
emit OwnershipTransferred(oldOwner, newOwner);
}
}
Contract Source Code
File 18 of 23: ReentrancyGuard.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts (last updated v4.8.0) (security/ReentrancyGuard.sol)pragmasolidity ^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].
*/abstractcontractReentrancyGuard{
// 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.uint256privateconstant _NOT_ENTERED =1;
uint256privateconstant _ENTERED =2;
uint256private _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.
*/modifiernonReentrant() {
_nonReentrantBefore();
_;
_nonReentrantAfter();
}
function_nonReentrantBefore() private{
// On the first call to nonReentrant, _status will be _NOT_ENTEREDrequire(_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;
}
}
Contract Source Code
File 19 of 23: SafeERC20.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts (last updated v4.8.0) (token/ERC20/utils/SafeERC20.sol)pragmasolidity ^0.8.0;import"../IERC20.sol";
import"../extensions/draft-IERC20Permit.sol";
import"../../../utils/Address.sol";
/**
* @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.
*/librarySafeERC20{
usingAddressforaddress;
functionsafeTransfer(
IERC20 token,
address to,
uint256 value
) internal{
_callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
}
functionsafeTransferFrom(
IERC20 token,
addressfrom,
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.
*/functionsafeApprove(
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));
}
functionsafeIncreaseAllowance(
IERC20 token,
address spender,
uint256 value
) internal{
uint256 newAllowance = token.allowance(address(this), spender) + value;
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
}
functionsafeDecreaseAllowance(
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));
}
}
functionsafePermit(
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, bytesmemory 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.bytesmemory returndata =address(token).functionCall(data, "SafeERC20: low-level call failed");
if (returndata.length>0) {
// Return data is optionalrequire(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
}
}
}
Contract Source Code
File 20 of 23: Strings.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts (last updated v4.8.0) (utils/Strings.sol)pragmasolidity ^0.8.0;import"./math/Math.sol";
/**
* @dev String operations.
*/libraryStrings{
bytes16privateconstant _SYMBOLS ="0123456789abcdef";
uint8privateconstant _ADDRESS_LENGTH =20;
/**
* @dev Converts a `uint256` to its ASCII `string` decimal representation.
*/functiontoString(uint256 value) internalpurereturns (stringmemory) {
unchecked {
uint256 length = Math.log10(value) +1;
stringmemory buffer =newstring(length);
uint256 ptr;
/// @solidity memory-safe-assemblyassembly {
ptr :=add(buffer, add(32, length))
}
while (true) {
ptr--;
/// @solidity memory-safe-assemblyassembly {
mstore8(ptr, byte(mod(value, 10), _SYMBOLS))
}
value /=10;
if (value ==0) break;
}
return buffer;
}
}
/**
* @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
*/functiontoHexString(uint256 value) internalpurereturns (stringmemory) {
unchecked {
return toHexString(value, Math.log256(value) +1);
}
}
/**
* @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
*/functiontoHexString(uint256 value, uint256 length) internalpurereturns (stringmemory) {
bytesmemory buffer =newbytes(2* length +2);
buffer[0] ="0";
buffer[1] ="x";
for (uint256 i =2* length +1; i >1; --i) {
buffer[i] = _SYMBOLS[value &0xf];
value >>=4;
}
require(value ==0, "Strings: hex length insufficient");
returnstring(buffer);
}
/**
* @dev Converts an `address` with fixed length of 20 bytes to its not checksummed ASCII `string` hexadecimal representation.
*/functiontoHexString(address addr) internalpurereturns (stringmemory) {
return toHexString(uint256(uint160(addr)), _ADDRESS_LENGTH);
}
}
Contract Source Code
File 21 of 23: draft-IERC20Permit.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/draft-IERC20Permit.sol)pragmasolidity ^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.
*/interfaceIERC20Permit{
/**
* @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].
*/functionpermit(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.
*/functionnonces(address owner) externalviewreturns (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-mixedcasefunctionDOMAIN_SEPARATOR() externalviewreturns (bytes32);
}
Contract Source Code
File 22 of 23: fixedQiVault.sol
// SPDX-License-Identifier: MITpragmasolidity 0.8.11;import"@openzeppelin/contracts/access/Ownable.sol";
import"./fixedVault.sol";
/// @title Fixed Interest Vault/// @notice Single collateral lending manager with fixed rate interest.contractstableQiVaultisfixedVault, Ownable{
/// @dev Used to restrain the fee. Can only be up to 5% of the amount.uint256constant FEE_MAX =500;
stringprivate oracleType;
constructor(address ethPriceSourceAddress,
uint256 minimumCollateralPercentage,
stringmemory name,
stringmemory symbol,
address _mai,
address _collateral,
stringmemory baseURI
)
fixedVault(
ethPriceSourceAddress,
minimumCollateralPercentage,
name,
symbol,
_mai,
_collateral,
baseURI
)
{
createVault();
addFrontEnd(0);
}
eventUpdatedClosingFee(uint256 newFee);
eventUpdatedOpeningFee(uint256 newFee);
eventWithdrawInterest(uint256 earned);
eventUpdatedMinDebt(uint256 newMinDebt);
eventUpdatedMaxDebt(uint256 newMaxDebt);
eventUpdatedDebtRatio(uint256 _debtRatio);
eventUpdatedGainRatio(uint256 _gainRatio);
eventUpdatedEthPriceSource(address _ethPriceSourceAddress);
eventAddedFrontEnd(uint256 promoter);
eventRemovedFrontEnd(uint256 promoter);
eventUpdatedFrontEnd(uint256 promoter, uint256 newFee);
eventUpdatedFees(uint256 _adminFee, uint256 _refFee);
eventUpdatedMinCollateralRatio(uint256 newMinCollateralRatio);
eventUpdatedStabilityPool(address pool);
eventUpdatedInterestRate(uint256 interestRate);
eventBurnedToken(uint256 amount);
eventUpdatedTokenURI(string uri);
eventUpdatedAdmin(address newAdmin);
eventUpdatedRef(address newRef);
eventUpdatedOracleName(string oracle);
eventUpdatedRouter(address router);
eventUpdatedCustomURI(bool custom);
modifieronlyOperators() {
require(ref ==msg.sender|| adm ==msg.sender|| owner() ==msg.sender, "Needs to be called by operators");
_;
}
modifieronlyAdmin() {
require(adm ==msg.sender, "Needs to be called by admin");
_;
}
/// @param _oracle name of the oracle used by the contract/// @notice sets the oracle name used by the contract. for visual purposes.functionupdateOracleName(stringmemory _oracle) externalonlyOwner{
oracleType = _oracle;
emit UpdatedOracleName(_oracle);
}
/// @param _gainRatio sets the bonus earned from a liquidator/// @notice implements a setter for the bonus earned by a liquidator/// @dev fails if the bonus is less than 1functionsetGainRatio(uint256 _gainRatio) externalonlyOwner{
require(_gainRatio >=1000, "gainRatio cannot be less than or equal to 1000");
gainRatio = _gainRatio;
emit UpdatedGainRatio(gainRatio);
}
/// @param _debtRatio sets the ratio of debt paid back by a liquidator/// @notice sets the ratio of the debt to be paid back/// @dev it divides the debt. 1/debtRatio.functionsetDebtRatio(uint256 _debtRatio) externalonlyOwner{
require(_debtRatio !=0, "Debt Ratio cannot be 0");
debtRatio = _debtRatio;
emit UpdatedDebtRatio(debtRatio);
}
/// @param ethPriceSourceAddress is the address that provides the price of the collateral/// @notice sets the address used as oracle/// @dev Oracle price feed is used in here. Interface's available in the at /interfaces/IPriceSourceAll.solfunctionchangeEthPriceSource(address ethPriceSourceAddress)
externalonlyOwner{
require(ethPriceSourceAddress !=address(0), "Ethpricesource cannot be zero address" );
ethPriceSource = IPriceSource(ethPriceSourceAddress);
emit UpdatedEthPriceSource(ethPriceSourceAddress);
}
/// @param _pool is the address that can execute liquidations/// @notice sets the address used as stability pool for liquidations/// @dev if not set to address(0) then _pool is the only address able to liquidatefunctionsetStabilityPool(address _pool) externalonlyOwner{
require(_pool !=address(0), "StabilityPool cannot be zero address" );
stabilityPool = _pool;
emit UpdatedStabilityPool(stabilityPool);
}
/// @param _admin is the ratio earned by the address that maintains the market/// @param _ref is the ratio earned by the address that provides the borrowable asset/// @notice sets the interest rate split between the admin and ref/// @dev if not set to address(0) then _pool is the only address able to liquidatefunctionsetFees(uint256 _admin, uint256 _ref) externalonlyOwner{
require((_admin+_ref)==TEN_THOUSAND, "setFees: must equal 10000.");
adminFee=_admin;
refFee=_ref;
emit UpdatedFees(adminFee, refFee);
}
/// @param minimumCollateralPercentage is the CDR that limits the amount borrowed/// @notice sets the CDR/// @dev only callable by owner of the contractfunctionsetMinCollateralRatio(uint256 minimumCollateralPercentage)
externalonlyOwner{
_minimumCollateralPercentage = minimumCollateralPercentage;
emit UpdatedMinCollateralRatio(_minimumCollateralPercentage);
}
/// @param _minDebt is minimum debt able to be borrowed by a vault./// @notice sets the minimum debt./// @dev dust protectionfunctionsetMinDebt(uint256 _minDebt)
externalonlyOwner{
require(_minDebt >=0, "setMinDebt: must be over 0.");
minDebt = _minDebt;
emit UpdatedMinDebt(minDebt);
}
/// @param _maxDebt is maximum debt able to be borrowed by a vault./// @notice sets the maximum debt./// @dev whale and liquidity protection.functionsetMaxDebt(uint256 _maxDebt)
externalonlyOwner{
require(_maxDebt >=0, "setMaxDebt: must be over 0.");
maxDebt = _maxDebt;
emit UpdatedMaxDebt(maxDebt);
}
/// @param _ref is the address that provides the borrowable asset/// @notice sets the address that earns interest for providing a borrowable asset/// @dev cannot be address(0)functionsetRef(address _ref) externalonlyOwner{
require(_ref !=address(0), "Reference Address cannot be zero");
ref = _ref;
emit UpdatedRef(ref);
}
/// @param _adm is the ratio earned by the address that maintains the market/// @notice sets the address that earns interest for maintaining the market/// @dev cannot be address(0)functionsetAdmin(address _adm) externalonlyOwner{
require(_adm !=address(0), "Admin Address cannot be zero");
adm = _adm;
emit UpdatedAdmin(adm);
}
/// @param _openingFee is the fee charged to a vault when borrowing./// @notice sets opening fee./// @dev can only be up to 5% (FEE_MAX) of the amount.functionsetOpeningFee(uint256 _openingFee) externalonlyOwner{
require(_openingFee >=0&& _openingFee <= FEE_MAX, "setOpeningFee: cannot be more than 5%");
openingFee = _openingFee;
// emit eventemit UpdatedOpeningFee(openingFee);
}
/// @param _closingFee is the fee charged to a vault when repaying./// @notice sets closing fee./// @dev can only be up to 5% (FEE_MAX) of the amount.functionsetClosingFee(uint256 _closingFee) externalonlyOwner{
require(_closingFee >=0&& _closingFee <= FEE_MAX, "setClosingFee: cannot be more than 5%");
closingFee = _closingFee;
// emit eventemit UpdatedClosingFee(closingFee);
}
/// @param _promoter is a front end for the contract/// @notice adds a front end to earn opening/closing fees from borrowing/repaying./// @dev can only be up to 5% (FEE_MAX) of the amount.functionaddFrontEnd(uint256 _promoter) publiconlyOwner{
require(_exists(_promoter), "addFrontEnd: Vault does not exist");
require(promoter[_promoter] ==0, "addFrontEnd: already added");
promoter[_promoter] = TEN_THOUSAND;
emit AddedFrontEnd(_promoter);
}
/// @param _promoter is a front end for the contract/// @param cashback is the amount of fee not taken from a user./// @notice updates the cashback variable for a given front end/// @dev can only be updated by the front end vault's ownerfunctionupdateFrontEnd(uint256 _promoter, uint256 cashback) externalfrontExists(_promoter) onlyVaultOwner(_promoter) {
require(cashback >0&& cashback <= TEN_THOUSAND, "updateFrontEnd: cannot be 0");
promoter[_promoter] = cashback;
emit UpdatedFrontEnd(_promoter, cashback);
}
/// @param _promoter is a front end for the contract/// @notice removes the ability for a front end to earn feesfunctionremoveFrontEnd(uint256 _promoter) externalfrontExists(_promoter) onlyOwner{
require(_exists(_promoter), "removeFrontEnd: Vault does not exist");
require(promoter[_promoter] >0, "removeFrontEnd: not a front end");
promoter[_promoter] =0;
emit RemovedFrontEnd(_promoter);
}
/// @notice withdraws earned interest by vault.functionwithdrawInterest() externalonlyOperatorsnonReentrant{
uint256 adm_fee = maiDebt*adminFee / TEN_THOUSAND;
// Transfer
mai.transfer(ref, (maiDebt-adm_fee) ); // cheaper and equivalent.
mai.transfer(adm, adm_fee);
emit WithdrawInterest(maiDebt);
maiDebt =0;
}
/// @param _iR is the fixed interest charged by a vault/// @notice sets the interest charged by a vault.functionsetInterestRate(uint256 _iR) externalonlyOwner{
iR = _iR;
emit UpdatedInterestRate(iR);
}
/// @param amountToken is the amount of borrowable asset that is removed from the debt ceiling./// @notice removes debt ceiling from the vault./// @dev returns the asset to the owner so it can be redeployed at a later time.functionburn(uint256 amountToken) externalonlyAdmin{
// Burnrequire(amountToken <= mai.balanceOf(address(this)), "burn: Balance not enough");
mai.transfer(ref, amountToken);
emit BurnedToken(amountToken);
}
/// @param _baseURI is the url for the nft metadata/// @notice updates the metadata/// @dev it currently uses an ipfs jsonfunctionsetTokenURI(stringcalldata _baseURI) externalonlyOwner{
baseURI = _baseURI;
emit UpdatedTokenURI(baseURI);
}
functionsetRouter(address _router) externalonlyOwner{
router=_router;
emit UpdatedRouter(router);
}
functionsetCustomURI(bool _custom) externalonlyOwner{
custom=_custom;
emit UpdatedCustomURI(custom);
}
}
Contract Source Code
File 23 of 23: fixedVault.sol
// SPDX-License-Identifier: MITpragmasolidity 0.8.11;import"@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import"@openzeppelin/contracts/token/ERC20/ERC20.sol";
import"@openzeppelin/contracts/security/ReentrancyGuard.sol";
import"../interfaces/external/IPriceSourceAll.sol";
import"../token/ERC721/MyVaultV5.sol";
contractfixedVaultisReentrancyGuard, VaultNFTv5{
usingSafeERC20forERC20;
/// @dev Constants used across the contract.uint256constant TEN_THOUSAND =10000;
uint256constant ONE_YEAR =31556952;
uint256constant THOUSAND =1000;
IPriceSource public ethPriceSource;
uint256public _minimumCollateralPercentage;
uint256public vaultCount;
uint256public closingFee;
uint256public openingFee;
uint256public minDebt;
uint256public maxDebt;
uint256constantpublic tokenPeg =1e8; // $1uint256public iR;
mapping(uint256=>uint256) public vaultCollateral;
mapping(uint256=>uint256) public accumulatedVaultDebt;
mapping(uint256=>uint256) public lastInterest;
mapping(uint256=>uint256) public promoter;
uint256public adminFee; // 10% of the earned interestuint256public refFee; // 90% of the earned interestuint256public debtRatio;
uint256public gainRatio;
ERC20 public collateral;
ERC20 public mai;
uint256public decimalDifferenceRaisedToTen;
uint256public priceSourceDecimals;
uint256public totalBorrowed;
mapping(address=>uint256) public maticDebt;
uint256public maiDebt;
addresspublic stabilityPool;
addresspublic adm;
addresspublic ref;
addresspublic router;
uint8public version =8;
eventCreateVault(uint256 vaultID, address creator);
eventDestroyVault(uint256 vaultID);
eventDepositCollateral(uint256 vaultID, uint256 amount);
eventWithdrawCollateral(uint256 vaultID, uint256 amount);
eventBorrowToken(uint256 vaultID, uint256 amount);
eventPayBackToken(uint256 vaultID, uint256 amount, uint256 closingFee);
eventLiquidateVault(uint256 vaultID,
address owner,
address buyer,
uint256 debtRepaid,
uint256 collateralLiquidated,
uint256 closingFee
);
eventBoughtRiskyDebtVault(uint256 riskyVault, uint256 newVault, address riskyVaultBuyer, uint256 amountPaidtoBuy);
constructor(address ethPriceSourceAddress,
uint256 minimumCollateralPercentage,
stringmemory name,
stringmemory symbol,
address _mai,
address _collateral,
stringmemory baseURI
) VaultNFTv5(name, symbol, baseURI) {
require(ethPriceSourceAddress !=address(0));
require(minimumCollateralPercentage !=0);
closingFee =50; // 0.5%
openingFee =0; // 0.0%
ethPriceSource = IPriceSource(ethPriceSourceAddress);
stabilityPool =address(0);
maxDebt =500000ether; //Keeping maxDebt at 500K * 10^(18)
debtRatio =2; // 1/2, pay back 50%
gainRatio =1100; // /10 so 1.1
_minimumCollateralPercentage = minimumCollateralPercentage;
collateral = ERC20(_collateral);
mai = ERC20(_mai);
priceSourceDecimals =8;
/*
This works only for collaterals with decimals < 18
*/
decimalDifferenceRaisedToTen =10**(mai.decimals() - collateral.decimals());
adm =msg.sender;
ref =msg.sender;
}
modifieronlyVaultOwner(uint256 vaultID) {
require(_exists(vaultID), "Vault does not exist");
require(ownerOf(vaultID) ==msg.sender, "Vault is not owned by you");
_;
}
modifieronlyRouter() {
require(
router ==address(0) ||msg.sender== router,
"must use router"
);
_;
}
modifiervaultExists(uint256 vaultID) {
require(_exists(vaultID), "Vault does not exist");
_;
}
modifierfrontExists(uint256 vaultID) {
require(_exists(vaultID), "front end vault does not exist");
require(promoter[vaultID] <= TEN_THOUSAND && promoter[vaultID] >0, "Front end not added");
_;
}
/// @notice Return the current debt available to borrow./// @dev checks the outstanding balance of the borrowable asset within the contract./// @return available balance of borrowable asset.functiongetDebtCeiling() publicviewreturns (uint256) {
return mai.balanceOf(address(this));
}
/// @param vaultID is the token id of the vault being checked./// @notice Returns true if a vault exists/// @dev the erc721 spec allows users to burn/destroy their nft/// @return boolean if the vault existsfunctionexists(uint256 vaultID) externalviewreturns (bool) {
return _exists(vaultID);
}
/// @notice Returns the total value locked in the vault, based on the oracle price./// @return uint256 total value locked in vaultfunctiongetTotalValueLocked() externalviewreturns (uint256) {
return ( getEthPriceSource() * decimalDifferenceRaisedToTen * collateral.balanceOf(address(this)) ) ; //extra 1e8, to get fraction in ui// 1e8 * 1eDelta
}
/// @notice Return the fee charged when repaying a vault./// @return uint256 is the fee charged to a vault when repaying.functiongetClosingFee() externalviewreturns (uint256) {
return closingFee;
}
/// @notice Return the peg maintained by the vault./// @return uint256 is the value with 8 decimals used to calculate borrowable debt.functiongetTokenPriceSource() publicviewreturns (uint256) {
return tokenPeg;
}
/// @notice Return the collateral value/// @return uint256 is the value retrieved from the oracle used/// to calculate the available borrowable amounts.functiongetEthPriceSource() publicviewreturns (uint256) {
return ethPriceSource.latestAnswer();
}
/// @param vaultID is the token id of the vault being checked./// @notice Returns the debt owned by the vault and the interest accrued over time./// @return uint256 fee earned in the time between updates/// @return uint256 debt owed by the vault for further calculation.function_vaultDebtAndFee(uint256 vaultID)
internalviewreturns (uint256, uint256)
{
uint256 currentTime =block.timestamp;
uint256 debt = accumulatedVaultDebt[vaultID];
uint256 fee =0;
if (lastInterest[vaultID] !=0&& iR >0) {
uint256 timeDelta = currentTime - lastInterest[vaultID];
uint256 feeAccrued = (((iR * debt) * timeDelta) / ONE_YEAR) / TEN_THOUSAND;
fee = feeAccrued;
debt = feeAccrued + debt;
}
return (fee, debt);
}
/// @param vaultID is the token id of the vault being checked./// @notice Returns the debt owned by the vault without tracking the interest/// @return uint256 debt owed by the vault for further calculation.functionvaultDebt(uint256 vaultID) publicviewreturns (uint256) {
(, uint256 debt) = _vaultDebtAndFee(vaultID);
return debt;
}
/// @param vaultID is the token id of the vault being checked./// @notice Adds the interest charged to the vault over the previous time called./// @return uint256 latest vault debtfunctionupdateVaultDebt(uint256 vaultID) publicreturns (uint256) {
(uint256 fee, uint256 debt) = _vaultDebtAndFee(vaultID);
maiDebt = maiDebt + fee;
totalBorrowed = totalBorrowed + fee;
if(iR >0) {
lastInterest[vaultID] =block.timestamp;
}
// we can just update the current vault debt here instead
accumulatedVaultDebt[vaultID] = debt;
return debt;
}
/// @param _collateral is the amount of collateral tokens to be valued./// @param _debt is the debt owed by the vault./// @notice Returns collateral value and debt based on the oracle prices/// @return uint256 coolateral value * 100. used to calculate the CDR/// @return uint256 debt value. Uses token price source to derive.functioncalculateCollateralProperties(uint256 _collateral, uint256 _debt)
privateviewreturns (uint256, uint256)
{
require(getEthPriceSource() !=0);
require(getTokenPriceSource() !=0);
uint256 collateralValue = _collateral *
getEthPriceSource() *
decimalDifferenceRaisedToTen;
require(collateralValue >= _collateral);
uint256 debtValue = _debt * getTokenPriceSource();
require(debtValue >= _debt);
uint256 collateralValueTimes100 = collateralValue *100;
require(collateralValueTimes100 > collateralValue);
return (collateralValueTimes100, debtValue);
}
/// @param _collateral is the amount of collateral tokens held by vault./// @param debt is the debt owed by the vault./// @notice Calculates if the CDR is valid before taking a further action with a user/// @return boolean describing if the new CDR is valid.functionisValidCollateral(uint256 _collateral, uint256 debt)
publicviewreturns (bool)
{
(
uint256 collateralValueTimes100,
uint256 debtValue
) = calculateCollateralProperties(_collateral, debt);
uint256 collateralPercentage = collateralValueTimes100 / debtValue;
return collateralPercentage >= _minimumCollateralPercentage;
}
/// @param fee is the amount of basis points (BP) to charge/// @param amount is the total value to calculate the BPs from/// @param promoFee is the fee charged by the front end/// @notice Returns fee to charge based on the collateral amount/// @return uint256 fee to charge the collateral./// @dev fee can be called on web app to compare charges.functioncalculateFee(uint256 fee,
uint256 amount,
uint256 promoFee
) publicviewreturns (uint256) {
uint256 _fee;
if (promoFee>0) {
_fee = ((amount * fee * getTokenPriceSource() * promoFee) /
(getEthPriceSource() * TEN_THOUSAND * TEN_THOUSAND));
} else {
_fee = (amount * fee * getTokenPriceSource()) /
(getEthPriceSource() * TEN_THOUSAND);
}
return _fee / decimalDifferenceRaisedToTen;
}
/// @notice Creates a new ERC721 Vault NFT/// @return uint256 the token id of the vault created.functioncreateVault() publicreturns (uint256) {
uint256 id = vaultCount;
vaultCount = vaultCount +1;
require(vaultCount >= id);
_mint(msg.sender, id);
emit CreateVault(id, msg.sender);
return id;
}
/// @notice Destroys an ERC721 Vault NFT/// @param vaultID the vault ID to destroy/// @dev vault must not have any debt owed to be able to be destroyed.functiondestroyVault(uint256 vaultID)
externalonlyVaultOwner(vaultID)
nonReentrant{
require(vaultDebt(vaultID) ==0, "Vault has outstanding debt");
if (vaultCollateral[vaultID] !=0) {
// withdraw leftover collateral
collateral.safeTransfer(ownerOf(vaultID), vaultCollateral[vaultID]);
}
_burn(vaultID);
delete vaultCollateral[vaultID];
delete accumulatedVaultDebt[vaultID];
delete lastInterest[vaultID];
emit DestroyVault(vaultID);
}
/// @param vaultID is the token id of the vault being interacted with./// @param amount is the amount of collateral to deposit from msg.sender/// @notice Adds collateral to a specific vault by token id/// @dev Any address can deposit into a vaultfunctiondepositCollateral(uint256 vaultID, uint256 amount)
externalvaultExists(vaultID)
onlyRouter{
uint256 newCollateral = vaultCollateral[vaultID] + (amount);
require(newCollateral >= vaultCollateral[vaultID]);
vaultCollateral[vaultID] = newCollateral;
collateral.safeTransferFrom(msg.sender, address(this), amount);
emit DepositCollateral(vaultID, amount);
}
/// @param vaultID is the token id of the vault being interacted with./// @param amount is the amount of collateral to withdraw/// @notice withdraws collateral to a specific vault by token id/// @dev If there is debt, then it can only withdraw up to the min CDR.functionwithdrawCollateral(uint256 vaultID, uint256 amount)
externalonlyVaultOwner(vaultID)
nonReentrant{
require(
vaultCollateral[vaultID] >= amount,
"Vault does not have enough collateral"
);
uint256 newCollateral = vaultCollateral[vaultID] - amount;
uint256 debt = updateVaultDebt(vaultID);
if (debt !=0) {
require(
isValidCollateral(newCollateral, debt),
"Withdrawal would put vault below minimum collateral percentage"
);
}
vaultCollateral[vaultID] = newCollateral;
collateral.safeTransfer(msg.sender, amount);
emit WithdrawCollateral(vaultID, amount);
}
/// @param vaultID is the token id of the vault being interacted with./// @param amount is the amount of borrowable asset to borrow/// @notice borrows asset based on the collateral held and the price of the collateral./// @dev Borrowing is limited by the CDR of the vault/// If there's opening fee, it will be charged here.functionborrowToken(uint256 vaultID,
uint256 amount,
uint256 _front
) externalfrontExists(_front)
onlyVaultOwner(vaultID)
nonReentrant{
require(amount >0, "Must borrow non-zero amount");
require(
amount <= getDebtCeiling(),
"borrowToken: Cannot mint over available supply."
);
uint256 newDebt = updateVaultDebt(vaultID) + amount;
require(newDebt<=maxDebt, "borrowToken: max loan cap reached.");
require(newDebt > vaultDebt(vaultID));
require(
isValidCollateral(vaultCollateral[vaultID], newDebt),
"Borrow would put vault below minimum collateral percentage"
);
require(
((vaultDebt(vaultID)) + amount) >= minDebt,
"Vault debt can't be under minDebt"
);
accumulatedVaultDebt[vaultID] = newDebt;
uint256 _openingFee = calculateFee(openingFee, newDebt, promoter[_front]);
vaultCollateral[vaultID] = vaultCollateral[vaultID] - (_openingFee);
vaultCollateral[_front] = vaultCollateral[_front] + (_openingFee);
// mai
mai.safeTransfer(msg.sender, amount);
totalBorrowed = totalBorrowed + (amount);
emit BorrowToken(vaultID, amount);
}
functionpaybackTokenAll(uint256 vaultID,
uint256 deadline,
uint256 _front
) externalfrontExists(_front) vaultExists(vaultID) onlyRouter{
require(
deadline >=block.timestamp,
"paybackTokenAll: deadline expired."
);
uint256 _amount = updateVaultDebt(vaultID);
payBackToken(vaultID, _amount, _front);
}
/// @param vaultID is the token id of the vault being interacted with./// @param amount is the amount of borrowable asset to repay/// @param _front is the front end that will get the opening/// @notice payback asset to close loan./// @dev If there is debt, then it can only withdraw up to the min CDR.functionpayBackToken(uint256 vaultID,
uint256 amount,
uint256 _front
) publicfrontExists(_front) vaultExists(vaultID) onlyRouter{
require(mai.balanceOf(msg.sender) >= amount, "Token balance too low");
uint256 vaultDebtNow = updateVaultDebt(vaultID);
require(
vaultDebtNow >= amount,
"Vault debt less than amount to pay back"
);
require(
((vaultDebtNow) - amount) >= minDebt || amount == (vaultDebtNow),
"Vault debt can't be under minDebt"
);
uint256 _closingFee = calculateFee(
closingFee,
amount,
promoter[_front]
);
accumulatedVaultDebt[vaultID] = vaultDebtNow - amount;
vaultCollateral[vaultID] = vaultCollateral[vaultID] - _closingFee;
vaultCollateral[_front] = vaultCollateral[_front] + _closingFee;
totalBorrowed = totalBorrowed - amount;
//mai
mai.safeTransferFrom(msg.sender, address(this), amount);
emit PayBackToken(vaultID, amount, _closingFee);
}
/// @notice withdraws liquidator earnings./// @dev reverts if there's no collateral to withdraw.functiongetPaid() externalnonReentrant{
require(maticDebt[msg.sender] !=0, "Don't have anything for you.");
uint256 amount = maticDebt[msg.sender];
maticDebt[msg.sender] =0;
collateral.safeTransfer(msg.sender, amount);
}
/// @param pay is address of the person to getPaid/// @notice withdraws liquidator earnings./// @dev reverts if there's no collateral to withdraw.functiongetPaid(address pay) externalnonReentrant{
require(maticDebt[pay] !=0, "Don't have anything for you.");
uint256 amount = maticDebt[pay];
maticDebt[pay] =0;
collateral.safeTransfer(pay, amount);
}
/// @param vaultID is the token id of the vault being interacted with./// @notice Calculates cost to liquidate a vault/// @dev Can be used to calculate balance required to liquidate a vault. functioncheckCost(uint256 vaultID) publicviewreturns (uint256) {
uint256 vaultDebtNow = vaultDebt(vaultID);
if (
vaultCollateral[vaultID] ==0||
vaultDebtNow ==0||!checkLiquidation(vaultID)
) {
return0;
}
(,
uint256 debtValue
) = calculateCollateralProperties(
vaultCollateral[vaultID],
vaultDebtNow
);
if (debtValue ==0) {
return0;
}
debtValue = debtValue / (10**priceSourceDecimals);
uint256 halfDebt = debtValue / debtRatio; //debtRatio (2)if (halfDebt <= minDebt) {
halfDebt = debtValue;
}
return (halfDebt);
}
/// @param vaultID is the token id of the vault being interacted with./// @notice Calculates collateral to extract when liquidating a vault/// @dev Can be used to calculate earnings from liquidating a vault. functioncheckExtract(uint256 vaultID) publicviewreturns (uint256) {
if (vaultCollateral[vaultID] ==0||!checkLiquidation(vaultID)) {
return0;
}
uint256 vaultDebtNow = vaultDebt(vaultID);
(, uint256 debtValue) = calculateCollateralProperties(
vaultCollateral[vaultID],
vaultDebtNow
);
uint256 halfDebt = debtValue / debtRatio; //debtRatio (2)if (halfDebt ==0) {
return0;
}
if ((halfDebt) / (10**priceSourceDecimals) <= minDebt) {
// full liquidation if under the min debt.return (debtValue * ( gainRatio)) / (THOUSAND) / (getEthPriceSource()) / decimalDifferenceRaisedToTen;
} else {
return (halfDebt * (gainRatio)) / THOUSAND / (getEthPriceSource()) / decimalDifferenceRaisedToTen;
}
}
/// @param vaultID is the token id of the vault being interacted with./// @notice Calculates the collateral percentage of a vault.functioncheckCollateralPercentage(uint256 vaultID)
publicviewvaultExists(vaultID)
returns (uint256)
{
uint256 vaultDebtNow = vaultDebt(vaultID);
if (vaultCollateral[vaultID] ==0|| vaultDebtNow ==0) {
return0;
}
(
uint256 collateralValueTimes100,
uint256 debtValue
) = calculateCollateralProperties(
vaultCollateral[vaultID],
vaultDebtNow
);
return collateralValueTimes100 / (debtValue);
}
/// @param vaultID is the token id of the vault being interacted with./// @notice Calculates if a vault is liquidatable./// @return bool if vault is liquidatable or not.functioncheckLiquidation(uint256 vaultID)
publicviewvaultExists(vaultID)
returns (bool)
{
uint256 vaultDebtNow = vaultDebt(vaultID);
if (vaultCollateral[vaultID] ==0|| vaultDebtNow ==0) {
returnfalse;
}
(
uint256 collateralValueTimes100,
uint256 debtValue
) = calculateCollateralProperties(
vaultCollateral[vaultID],
vaultDebtNow
);
uint256 collateralPercentage = collateralValueTimes100 / (debtValue);
if (collateralPercentage < _minimumCollateralPercentage) {
returntrue;
} else {
returnfalse;
}
}
/// @param vaultID is the token id of the vault being interacted with./// @notice Calculates if a vault is risky and can be bought./// @return bool if vault is risky or not.functioncheckRiskyVault(uint256 vaultID) publicviewvaultExists(vaultID) returns (bool) {
uint256 vaultDebtNow = vaultDebt(vaultID);
if (vaultCollateral[vaultID] ==0|| vaultDebtNow ==0) {
returnfalse;
}
(
uint256 collateralValueTimes100,
uint256 debtValue
) = calculateCollateralProperties(
vaultCollateral[vaultID],
vaultDebtNow
);
uint256 collateralPercentage = collateralValueTimes100 / (debtValue);
if ((collateralPercentage*10) <= gainRatio) {
returntrue;
} else {
returnfalse;
}
}
/// @param vaultID is the token id of the vault being interacted with./// @notice Pays back the part of the debt owed by the vault and removes a /// comparable amount of collateral plus bonus/// @dev if vault CDR is under the bonus ratio,/// then it will only be able to be bought through buy risky./// Amount to pay back is based on debtRatio variable.functionliquidateVault(uint256 vaultID, uint256 _front)
externalfrontExists(_front)
vaultExists(vaultID)
{
require(
stabilityPool ==address(0) ||msg.sender== stabilityPool,
"liquidation is disabled for public"
);
uint256 vaultDebtNow = updateVaultDebt(vaultID);
(
uint256 collateralValueTimes100,
uint256 debtValue
) = calculateCollateralProperties(
vaultCollateral[vaultID],
vaultDebtNow
);
require(vaultDebtNow !=0, "Vault debt is 0");
uint256 collateralPercentage = collateralValueTimes100 / (debtValue);
require(
collateralPercentage < _minimumCollateralPercentage,
"Vault is not below minimum collateral percentage"
);
require(collateralPercentage *10> gainRatio , "Vault is not above gain ratio");
debtValue = debtValue / (10**priceSourceDecimals);
uint256 halfDebt = debtValue / (debtRatio); //debtRatio (2)if (halfDebt <= minDebt) {
halfDebt = debtValue;
}
require(
mai.balanceOf(msg.sender) >= halfDebt,
"Token balance too low to pay off outstanding debt"
);
totalBorrowed = totalBorrowed - (halfDebt);
uint256 maticExtract = checkExtract(vaultID);
accumulatedVaultDebt[vaultID] = vaultDebtNow - (halfDebt); // we paid back half of its debt.uint256 _closingFee = calculateFee(closingFee, halfDebt, promoter[_front]);
vaultCollateral[vaultID] = vaultCollateral[vaultID] - (_closingFee);
vaultCollateral[_front] = vaultCollateral[_front] + (_closingFee);
// deduct the amount from the vault's collateral
vaultCollateral[vaultID] = vaultCollateral[vaultID] - (maticExtract);
// let liquidator take the collateral
maticDebt[msg.sender] = maticDebt[msg.sender] + (maticExtract);
//mai
mai.safeTransferFrom(msg.sender, address(this), halfDebt);
emit LiquidateVault(
vaultID,
ownerOf(vaultID),
msg.sender,
halfDebt,
maticExtract,
_closingFee
);
}
/// @param vaultID is the token id of the vault being interacted with./// @notice Pays back the debt owed to bring it back to min CDR. /// And transfers ownership of it to the liquidator with a new vault/// @return uint256 new vault created with the debt and collateral./// @dev this function can only be called if vault CDR is under the bonus ratio./// address who calls it will now own the debt and the collateral.functionbuyRiskDebtVault(uint256 vaultID) externalvaultExists(vaultID) nonReentrantreturns(uint256) {
require(
stabilityPool ==address(0) ||msg.sender== stabilityPool,
"buy risky is disabled for public"
);
uint256 vaultDebtNow = updateVaultDebt(vaultID);
require(vaultDebtNow !=0, "Vault debt is 0");
(
uint256 collateralValueTimes100,
uint256 debtValue
) = calculateCollateralProperties(
vaultCollateral[vaultID],
vaultDebtNow
);
uint256 collateralPercentage = collateralValueTimes100 / (debtValue);
require(
(collateralPercentage*10) <= gainRatio,
"Vault is not below risky collateral percentage"
);
uint256 maiDebtTobePaid = (debtValue / (10**priceSourceDecimals)) -
(collateralValueTimes100 /
( _minimumCollateralPercentage * (10**priceSourceDecimals)));
//have enough MAI to bring vault to X CDR (presumably min)require(mai.balanceOf(msg.sender) >= maiDebtTobePaid, "Not enough mai to buy the risky vault");
//mai
mai.safeTransferFrom(msg.sender, address(this), maiDebtTobePaid);
totalBorrowed = totalBorrowed - (maiDebtTobePaid);
// newVault for msg.senderuint256 newVault = createVault();
// updating vault collateral and debt details for the transfer of risky vault
vaultCollateral[newVault] = vaultCollateral[vaultID];
accumulatedVaultDebt[newVault] = vaultDebtNow - maiDebtTobePaid;
lastInterest[newVault] =block.timestamp;
// resetting the vaultID vault infodelete vaultCollateral[vaultID];
delete accumulatedVaultDebt[vaultID];
// lastInterest of vaultID would be block.timestamp, not reseting its timestampemit BoughtRiskyDebtVault(vaultID, newVault, msg.sender, maiDebtTobePaid);
return newVault;
}
}