Contract Source Code:
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (access/Ownable.sol)
pragma solidity ^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.
*/
abstract contract Ownable is Context {
address private _owner;
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @dev Initializes the contract setting the deployer as the initial owner.
*/
constructor() {
_transferOwnership(_msgSender());
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
_checkOwner();
_;
}
/**
* @dev Returns the address of the current owner.
*/
function owner() public view virtual returns (address) {
return _owner;
}
/**
* @dev Throws if the sender is not the owner.
*/
function _checkOwner() internal view virtual {
require(owner() == _msgSender(), "Ownable: caller is not the owner");
}
/**
* @dev Leaves the contract without owner. It will not be possible to call
* `onlyOwner` functions. Can only be called by the current owner.
*
* NOTE: Renouncing ownership will leave the contract without an owner,
* thereby disabling any functionality that is only available to the owner.
*/
function renounceOwnership() public virtual onlyOwner {
_transferOwnership(address(0));
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Can only be called by the current owner.
*/
function transferOwnership(address newOwner) public virtual onlyOwner {
require(newOwner != address(0), "Ownable: new owner is the zero address");
_transferOwnership(newOwner);
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Internal function without access restriction.
*/
function _transferOwnership(address newOwner) internal virtual {
address oldOwner = _owner;
_owner = newOwner;
emit OwnershipTransferred(oldOwner, newOwner);
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (security/ReentrancyGuard.sol)
pragma solidity ^0.8.0;
/**
* @dev Contract module that helps prevent reentrant calls to a function.
*
* Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
* available, which can be applied to functions to make sure there are no nested
* (reentrant) calls to them.
*
* Note that because there is a single `nonReentrant` guard, functions marked as
* `nonReentrant` may not call one another. This can be worked around by making
* those functions `private`, and then adding `external` `nonReentrant` entry
* points to them.
*
* TIP: If you would like to learn more about reentrancy and alternative ways
* to protect against it, check out our blog post
* https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
*/
abstract contract ReentrancyGuard {
// Booleans are more expensive than uint256 or any type that takes up a full
// word because each write operation emits an extra SLOAD to first read the
// slot's contents, replace the bits taken up by the boolean, and then write
// back. This is the compiler's defense against contract upgrades and
// pointer aliasing, and it cannot be disabled.
// The values being non-zero value makes deployment a bit more expensive,
// but in exchange the refund on every call to nonReentrant will be lower in
// amount. Since refunds are capped to a percentage of the total
// transaction's gas, it is best to keep them low in cases like this one, to
// increase the likelihood of the full refund coming into effect.
uint256 private constant _NOT_ENTERED = 1;
uint256 private constant _ENTERED = 2;
uint256 private _status;
constructor() {
_status = _NOT_ENTERED;
}
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
* Calling a `nonReentrant` function from another `nonReentrant`
* function is not supported. It is possible to prevent this from happening
* by making the `nonReentrant` function external, and making it call a
* `private` function that does the actual work.
*/
modifier nonReentrant() {
_nonReentrantBefore();
_;
_nonReentrantAfter();
}
function _nonReentrantBefore() private {
// On the first call to nonReentrant, _status will be _NOT_ENTERED
require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
// Any calls to nonReentrant after this point will fail
_status = _ENTERED;
}
function _nonReentrantAfter() private {
// By storing the original value once again, a refund is triggered (see
// https://eips.ethereum.org/EIPS/eip-2200)
_status = _NOT_ENTERED;
}
/**
* @dev Returns true if the reentrancy guard is currently set to "entered", which indicates there is a
* `nonReentrant` function in the call stack.
*/
function _reentrancyGuardEntered() internal view returns (bool) {
return _status == _ENTERED;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.4) (token/ERC20/extensions/IERC20Permit.sol)
pragma solidity ^0.8.0;
/**
* @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
* https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
*
* Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
* presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
* need to send a transaction, and thus is not required to hold Ether at all.
*
* ==== Security Considerations
*
* There are two important considerations concerning the use of `permit`. The first is that a valid permit signature
* expresses an allowance, and it should not be assumed to convey additional meaning. In particular, it should not be
* considered as an intention to spend the allowance in any specific way. The second is that because permits have
* built-in replay protection and can be submitted by anyone, they can be frontrun. A protocol that uses permits should
* take this into consideration and allow a `permit` call to fail. Combining these two aspects, a pattern that may be
* generally recommended is:
*
* ```solidity
* function doThingWithPermit(..., uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s) public {
* try token.permit(msg.sender, address(this), value, deadline, v, r, s) {} catch {}
* doThing(..., value);
* }
*
* function doThing(..., uint256 value) public {
* token.safeTransferFrom(msg.sender, address(this), value);
* ...
* }
* ```
*
* Observe that: 1) `msg.sender` is used as the owner, leaving no ambiguity as to the signer intent, and 2) the use of
* `try/catch` allows the permit to fail and makes the code tolerant to frontrunning. (See also
* {SafeERC20-safeTransferFrom}).
*
* Additionally, note that smart contract wallets (such as Argent or Safe) are not able to produce permit signatures, so
* contracts should have entry points that don't rely on permit.
*/
interface IERC20Permit {
/**
* @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,
* given ``owner``'s signed approval.
*
* IMPORTANT: The same issues {IERC20-approve} has related to transaction
* ordering also apply here.
*
* Emits an {Approval} event.
*
* Requirements:
*
* - `spender` cannot be the zero address.
* - `deadline` must be a timestamp in the future.
* - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
* over the EIP712-formatted function arguments.
* - the signature must use ``owner``'s current nonce (see {nonces}).
*
* For more information on the signature format, see the
* https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
* section].
*
* CAUTION: See Security Considerations above.
*/
function permit(
address owner,
address spender,
uint256 value,
uint256 deadline,
uint8 v,
bytes32 r,
bytes32 s
) external;
/**
* @dev Returns the current nonce for `owner`. This value must be
* included whenever a signature is generated for {permit}.
*
* Every successful call to {permit} increases ``owner``'s nonce by one. This
* prevents a signature from being used multiple times.
*/
function nonces(address owner) external view returns (uint256);
/**
* @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.
*/
// solhint-disable-next-line func-name-mixedcase
function DOMAIN_SEPARATOR() external view returns (bytes32);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/IERC20.sol)
pragma solidity ^0.8.0;
/**
* @dev Interface of the ERC20 standard as defined in the EIP.
*/
interface IERC20 {
/**
* @dev Emitted when `value` tokens are moved from one account (`from`) to
* another (`to`).
*
* Note that `value` may be zero.
*/
event Transfer(address indexed from, address indexed to, uint256 value);
/**
* @dev Emitted when the allowance of a `spender` for an `owner` is set by
* a call to {approve}. `value` is the new allowance.
*/
event Approval(address indexed owner, address indexed spender, uint256 value);
/**
* @dev Returns the amount of tokens in existence.
*/
function totalSupply() external view returns (uint256);
/**
* @dev Returns the amount of tokens owned by `account`.
*/
function balanceOf(address account) external view returns (uint256);
/**
* @dev Moves `amount` tokens from the caller's account to `to`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transfer(address to, uint256 amount) external returns (bool);
/**
* @dev Returns the remaining number of tokens that `spender` will be
* allowed to spend on behalf of `owner` through {transferFrom}. This is
* zero by default.
*
* This value changes when {approve} or {transferFrom} are called.
*/
function allowance(address owner, address spender) external view returns (uint256);
/**
* @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* IMPORTANT: Beware that changing an allowance with this method brings the risk
* that someone may use both the old and the new allowance by unfortunate
* transaction ordering. One possible solution to mitigate this race
* condition is to first reduce the spender's allowance to 0 and set the
* desired value afterwards:
* https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
*
* Emits an {Approval} event.
*/
function approve(address spender, uint256 amount) external returns (bool);
/**
* @dev Moves `amount` tokens from `from` to `to` using the
* allowance mechanism. `amount` is then deducted from the caller's
* allowance.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transferFrom(address from, address to, uint256 amount) external returns (bool);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.3) (token/ERC20/utils/SafeERC20.sol)
pragma solidity ^0.8.0;
import "../IERC20.sol";
import "../extensions/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.
*/
library SafeERC20 {
using Address for address;
/**
* @dev Transfer `value` amount of `token` from the calling contract to `to`. If `token` returns no value,
* non-reverting calls are assumed to be successful.
*/
function safeTransfer(IERC20 token, address to, uint256 value) internal {
_callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
}
/**
* @dev Transfer `value` amount of `token` from `from` to `to`, spending the approval given by `from` to the
* calling contract. If `token` returns no value, non-reverting calls are assumed to be successful.
*/
function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
_callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
}
/**
* @dev Deprecated. This function has issues similar to the ones found in
* {IERC20-approve}, and its usage is discouraged.
*
* Whenever possible, use {safeIncreaseAllowance} and
* {safeDecreaseAllowance} instead.
*/
function safeApprove(IERC20 token, address spender, uint256 value) internal {
// safeApprove should only be called when setting an initial allowance,
// or when resetting it to zero. To increase and decrease it, use
// 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
require(
(value == 0) || (token.allowance(address(this), spender) == 0),
"SafeERC20: approve from non-zero to non-zero allowance"
);
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
}
/**
* @dev Increase the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
* non-reverting calls are assumed to be successful.
*/
function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
uint256 oldAllowance = token.allowance(address(this), spender);
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance + value));
}
/**
* @dev Decrease the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
* non-reverting calls are assumed to be successful.
*/
function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
unchecked {
uint256 oldAllowance = token.allowance(address(this), spender);
require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance - value));
}
}
/**
* @dev Set the calling contract's allowance toward `spender` to `value`. If `token` returns no value,
* non-reverting calls are assumed to be successful. Meant to be used with tokens that require the approval
* to be set to zero before setting it to a non-zero value, such as USDT.
*/
function forceApprove(IERC20 token, address spender, uint256 value) internal {
bytes memory approvalCall = abi.encodeWithSelector(token.approve.selector, spender, value);
if (!_callOptionalReturnBool(token, approvalCall)) {
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, 0));
_callOptionalReturn(token, approvalCall);
}
}
/**
* @dev Use a ERC-2612 signature to set the `owner` approval toward `spender` on `token`.
* Revert on invalid signature.
*/
function safePermit(
IERC20Permit token,
address owner,
address spender,
uint256 value,
uint256 deadline,
uint8 v,
bytes32 r,
bytes32 s
) internal {
uint256 nonceBefore = token.nonces(owner);
token.permit(owner, spender, value, deadline, v, r, s);
uint256 nonceAfter = token.nonces(owner);
require(nonceAfter == nonceBefore + 1, "SafeERC20: permit did not succeed");
}
/**
* @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
* on the return value: the return value is optional (but if data is returned, it must not be false).
* @param token The token targeted by the call.
* @param data The call data (encoded using abi.encode or one of its variants).
*/
function _callOptionalReturn(IERC20 token, bytes memory data) private {
// We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
// we're implementing it ourselves. We use {Address-functionCall} to perform this call, which verifies that
// the target address contains contract code and also asserts for success in the low-level call.
bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
require(returndata.length == 0 || abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation 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).
*
* This is a variant of {_callOptionalReturn} that silents catches all reverts and returns a bool instead.
*/
function _callOptionalReturnBool(IERC20 token, bytes memory data) private returns (bool) {
// 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 cannot use {Address-functionCall} here since this should return false
// and not revert is the subcall reverts.
(bool success, bytes memory returndata) = address(token).call(data);
return
success && (returndata.length == 0 || abi.decode(returndata, (bool))) && Address.isContract(address(token));
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/Address.sol)
pragma solidity ^0.8.1;
/**
* @dev Collection of functions related to the address type
*/
library Address {
/**
* @dev Returns true if `account` is a contract.
*
* [IMPORTANT]
* ====
* It is unsafe to assume that an address for which this function returns
* false is an externally-owned account (EOA) and not a contract.
*
* Among others, `isContract` will return false for the following
* types of addresses:
*
* - an externally-owned account
* - a contract in construction
* - an address where a contract will be created
* - an address where a contract lived, but was destroyed
*
* Furthermore, `isContract` will also return true if the target contract within
* the same transaction is already scheduled for destruction by `SELFDESTRUCT`,
* which only has an effect at the end of a transaction.
* ====
*
* [IMPORTANT]
* ====
* You shouldn't rely on `isContract` to protect against flash loan attacks!
*
* Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
* like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
* constructor.
* ====
*/
function isContract(address account) internal view returns (bool) {
// This method relies on extcodesize/address.code.length, which returns 0
// for contracts in construction, since the code is only stored at the end
// of the constructor execution.
return account.code.length > 0;
}
/**
* @dev Replacement for Solidity's `transfer`: sends `amount` wei to
* `recipient`, forwarding all available gas and reverting on errors.
*
* https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
* of certain opcodes, possibly making contracts go over the 2300 gas limit
* imposed by `transfer`, making them unable to receive funds via
* `transfer`. {sendValue} removes this limitation.
*
* https://consensys.net/diligence/blog/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/v0.8.0/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
*/
function sendValue(address payable recipient, uint256 amount) internal {
require(address(this).balance >= amount, "Address: insufficient balance");
(bool success, ) = recipient.call{value: amount}("");
require(success, "Address: unable to send value, recipient may have reverted");
}
/**
* @dev Performs a Solidity function call using a low level `call`. A
* plain `call` is an unsafe replacement for a function call: use this
* function instead.
*
* If `target` reverts with a revert reason, it is bubbled up by this
* function (like regular Solidity function calls).
*
* Returns the raw returned data. To convert to the expected return value,
* use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
*
* Requirements:
*
* - `target` must be a contract.
* - calling `target` with `data` must not revert.
*
* _Available since v3.1._
*/
function functionCall(address target, bytes memory data) internal returns (bytes memory) {
return 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._
*/
function functionCall(
address target,
bytes memory data,
string memory errorMessage
) internal returns (bytes memory) {
return functionCallWithValue(target, data, 0, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but also transferring `value` wei to `target`.
*
* Requirements:
*
* - the calling contract must have an ETH balance of at least `value`.
* - the called Solidity function must be `payable`.
*
* _Available since v3.1._
*/
function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
}
/**
* @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
* with `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCallWithValue(
address target,
bytes memory data,
uint256 value,
string memory errorMessage
) internal returns (bytes memory) {
require(address(this).balance >= value, "Address: insufficient balance for call");
(bool success, bytes memory 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._
*/
function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
return functionStaticCall(target, data, "Address: low-level static call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(
address target,
bytes memory data,
string memory errorMessage
) internal view returns (bytes memory) {
(bool success, bytes memory 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._
*/
function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
return functionDelegateCall(target, data, "Address: low-level delegate call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a delegate call.
*
* _Available since v3.4._
*/
function functionDelegateCall(
address target,
bytes memory data,
string memory errorMessage
) internal returns (bytes memory) {
(bool success, bytes memory 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._
*/
function verifyCallResultFromTarget(
address target,
bool success,
bytes memory returndata,
string memory errorMessage
) internal view returns (bytes memory) {
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 contract
require(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._
*/
function verifyCallResult(
bool success,
bytes memory returndata,
string memory errorMessage
) internal pure returns (bytes memory) {
if (success) {
return returndata;
} else {
_revert(returndata, errorMessage);
}
}
function _revert(bytes memory returndata, string memory errorMessage) private pure {
// Look for revert reason and bubble it up if present
if (returndata.length > 0) {
// The easiest way to bubble the revert reason is using memory via assembly
/// @solidity memory-safe-assembly
assembly {
let returndata_size := mload(returndata)
revert(add(32, returndata), returndata_size)
}
} else {
revert(errorMessage);
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.4) (utils/Context.sol)
pragma solidity ^0.8.0;
/**
* @dev Provides information about the current execution context, including the
* sender of the transaction and its data. While these are generally available
* via msg.sender and msg.data, they should not be accessed in such a direct
* manner, since when dealing with meta-transactions the account sending and
* paying for execution may not be the actual sender (as far as an application
* is concerned).
*
* This contract is only required for intermediate, library-like contracts.
*/
abstract contract Context {
function _msgSender() internal view virtual returns (address) {
return msg.sender;
}
function _msgData() internal view virtual returns (bytes calldata) {
return msg.data;
}
function _contextSuffixLength() internal view virtual returns (uint256) {
return 0;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/math/Math.sol)
pragma solidity ^0.8.0;
/**
* @dev Standard math utilities missing in the Solidity language.
*/
library Math {
enum Rounding {
Down, // Toward negative infinity
Up, // Toward infinity
Zero // Toward zero
}
/**
* @dev Returns the largest of two numbers.
*/
function max(uint256 a, uint256 b) internal pure returns (uint256) {
return a > b ? a : b;
}
/**
* @dev Returns the smallest of two numbers.
*/
function min(uint256 a, uint256 b) internal pure returns (uint256) {
return a < b ? a : b;
}
/**
* @dev Returns the average of two numbers. The result is rounded towards
* zero.
*/
function average(uint256 a, uint256 b) internal pure returns (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.
*/
function ceilDiv(uint256 a, uint256 b) internal pure returns (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.
*/
function mulDiv(uint256 x, uint256 y, uint256 denominator) internal pure returns (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 product
uint256 prod1; // Most significant 256 bits of the product
assembly {
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) {
// Solidity will revert if denominator == 0, unlike the div opcode on its own.
// The surrounding unchecked block does not change this fact.
// See https://docs.soliditylang.org/en/latest/control-structures.html#checked-or-unchecked-arithmetic.
return prod0 / denominator;
}
// Make sure the result is less than 2^256. Also prevents denominator == 0.
require(denominator > prod1, "Math: mulDiv overflow");
///////////////////////////////////////////////
// 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.
*/
function mulDiv(uint256 x, uint256 y, uint256 denominator, Rounding rounding) internal pure returns (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).
*/
function sqrt(uint256 a) internal pure returns (uint256) {
if (a == 0) {
return 0;
}
// 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.
*/
function sqrt(uint256 a, Rounding rounding) internal pure returns (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.
*/
function log2(uint256 value) internal pure returns (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.
*/
function log2(uint256 value, Rounding rounding) internal pure returns (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.
*/
function log10(uint256 value) internal pure returns (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.
*/
function log10(uint256 value, Rounding rounding) internal pure returns (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.
*/
function log256(uint256 value) internal pure returns (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 256, following the selected rounding direction, of a positive value.
* Returns 0 if given 0.
*/
function log256(uint256 value, Rounding rounding) internal pure returns (uint256) {
unchecked {
uint256 result = log256(value);
return result + (rounding == Rounding.Up && 1 << (result << 3) < value ? 1 : 0);
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/math/SafeMath.sol)
pragma solidity ^0.8.0;
// CAUTION
// This version of SafeMath should only be used with Solidity 0.8 or later,
// because it relies on the compiler's built in overflow checks.
/**
* @dev Wrappers over Solidity's arithmetic operations.
*
* NOTE: `SafeMath` is generally not needed starting with Solidity 0.8, since the compiler
* now has built in overflow checking.
*/
library SafeMath {
/**
* @dev Returns the addition of two unsigned integers, with an overflow flag.
*
* _Available since v3.4._
*/
function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
unchecked {
uint256 c = a + b;
if (c < a) return (false, 0);
return (true, c);
}
}
/**
* @dev Returns the subtraction of two unsigned integers, with an overflow flag.
*
* _Available since v3.4._
*/
function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
unchecked {
if (b > a) return (false, 0);
return (true, a - b);
}
}
/**
* @dev Returns the multiplication of two unsigned integers, with an overflow flag.
*
* _Available since v3.4._
*/
function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
unchecked {
// Gas optimization: this is cheaper than requiring 'a' not being zero, but the
// benefit is lost if 'b' is also tested.
// See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
if (a == 0) return (true, 0);
uint256 c = a * b;
if (c / a != b) return (false, 0);
return (true, c);
}
}
/**
* @dev Returns the division of two unsigned integers, with a division by zero flag.
*
* _Available since v3.4._
*/
function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
unchecked {
if (b == 0) return (false, 0);
return (true, a / b);
}
}
/**
* @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
*
* _Available since v3.4._
*/
function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
unchecked {
if (b == 0) return (false, 0);
return (true, a % b);
}
}
/**
* @dev Returns the addition of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `+` operator.
*
* Requirements:
*
* - Addition cannot overflow.
*/
function add(uint256 a, uint256 b) internal pure returns (uint256) {
return a + b;
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting on
* overflow (when the result is negative).
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
*
* - Subtraction cannot overflow.
*/
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
return a - b;
}
/**
* @dev Returns the multiplication of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `*` operator.
*
* Requirements:
*
* - Multiplication cannot overflow.
*/
function mul(uint256 a, uint256 b) internal pure returns (uint256) {
return a * b;
}
/**
* @dev Returns the integer division of two unsigned integers, reverting on
* division by zero. The result is rounded towards zero.
*
* Counterpart to Solidity's `/` operator.
*
* Requirements:
*
* - The divisor cannot be zero.
*/
function div(uint256 a, uint256 b) internal pure returns (uint256) {
return a / b;
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* reverting when dividing by zero.
*
* Counterpart to Solidity's `%` operator. This function uses a `revert`
* opcode (which leaves remaining gas untouched) while Solidity uses an
* invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
*
* - The divisor cannot be zero.
*/
function mod(uint256 a, uint256 b) internal pure returns (uint256) {
return a % b;
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting with custom message on
* overflow (when the result is negative).
*
* CAUTION: This function is deprecated because it requires allocating memory for the error
* message unnecessarily. For custom revert reasons use {trySub}.
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
*
* - Subtraction cannot overflow.
*/
function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
unchecked {
require(b <= a, errorMessage);
return a - b;
}
}
/**
* @dev Returns the integer division of two unsigned integers, reverting with custom message on
* division by zero. The result is rounded towards zero.
*
* Counterpart to Solidity's `/` operator. Note: this function uses a
* `revert` opcode (which leaves remaining gas untouched) while Solidity
* uses an invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
*
* - The divisor cannot be zero.
*/
function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
unchecked {
require(b > 0, errorMessage);
return a / b;
}
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* reverting with custom message when dividing by zero.
*
* CAUTION: This function is deprecated because it requires allocating memory for the error
* message unnecessarily. For custom revert reasons use {tryMod}.
*
* Counterpart to Solidity's `%` operator. This function uses a `revert`
* opcode (which leaves remaining gas untouched) while Solidity uses an
* invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
*
* - The divisor cannot be zero.
*/
function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
unchecked {
require(b > 0, errorMessage);
return a % b;
}
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
interface IBasisAsset {
function mint(address recipient, uint256 amount) external returns (bool);
function burn(uint256 amount) external;
function burnFrom(address from, uint256 amount) external;
function isOperator() external returns (bool);
function operator() external view returns (address);
function transferOperator(address newOperator_) external;
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
interface IMasonry {
function balanceOf(address _andras) external view returns (uint256);
function earned(address _andras) external view returns (uint256);
function canWithdraw(address _andras) external view returns (bool);
function canClaimReward(address _andras) external view returns (bool);
function epoch() external view returns (uint256);
function nextEpochPoint() external view returns (uint256);
function getTombPrice() external view returns (uint256);
function setOperator(address _operator) external;
function setLockUp(uint256 _withdrawLockupEpochs, uint256 _rewardLockupEpochs) external;
function stake(uint256 _amount) external;
function withdraw(uint256 _amount) external;
function exit() external;
function claimReward() external;
function allocateSeigniorage(uint256 _amount) external;
function governanceRecoverUnsupported(address _token, uint256 _amount, address _to) external;
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
interface IOracle {
function update() external;
function consult(address _token, uint256 _amountIn) external view returns (uint256 amountOut);
function twap(address _token, uint256 _amountIn) external view returns (uint256 _amountOut);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
library Babylonian {
function sqrt(uint256 y) internal pure returns (uint256 z) {
if (y > 3) {
z = y;
uint256 x = y / 2 + 1;
while (x < z) {
z = x;
x = (y / x + x) / 2;
}
} else if (y != 0) {
z = 1;
}
// else z = 0
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "@openzeppelin/contracts/utils/Context.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
contract Operator is Context, Ownable {
address private _operator;
event OperatorTransferred(address indexed previousOperator, address indexed newOperator);
constructor() {
_operator = _msgSender();
emit OperatorTransferred(address(0), _operator);
}
function operator() public view returns (address) {
return _operator;
}
modifier onlyOperator() {
require(_operator == msg.sender, "operator: caller is not the operator");
_;
}
function isOperator() public view returns (bool) {
return _msgSender() == _operator;
}
function transferOperator(address newOperator_) public onlyOwner {
_transferOperator(newOperator_);
}
function _transferOperator(address newOperator_) internal {
require(newOperator_ != address(0), "operator: zero address given for new operator");
emit OperatorTransferred(address(0), newOperator_);
_operator = newOperator_;
}
function _renounceOperator() public onlyOwner {
emit OperatorTransferred(_operator, address(0));
_operator = address(0);
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "@openzeppelin/contracts/utils/math/Math.sol";
import "@openzeppelin/contracts/utils/math/SafeMath.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import "@openzeppelin/contracts/security/ReentrancyGuard.sol";
import "./lib/Babylonian.sol";
import "./owner/Operator.sol";
import "./utils/ContractGuard.sol";
import "./interfaces/IBasisAsset.sol";
import "./interfaces/IOracle.sol";
import "./interfaces/IMasonry.sol";
import "./owner/Operator.sol";
contract Treasury is ContractGuard, Operator {
using SafeERC20 for IERC20;
using Address for address;
using SafeMath for uint256;
/* ========= CONSTANT VARIABLES ======== */
uint256 public constant PERIOD = 6 hours;
/* ========== STATE VARIABLES ========== */
// flags
bool public initialized = false;
// epoch
uint256 public startTime;
uint256 public epoch = 0;
uint256 public epochSupplyContractionLeft = 0;
//=================================================================// exclusions from total supply
address[] public excludedFromTotalSupply = [
address(0x29D0762f7bE8409d0aC34A3595AF62E8c0120950) // SnakeGenesisRewardPool
];
// core components
address public snake;
address public bsnake;
address public gsnake;
address public masonry;
address public snakeOracle;
// price
uint256 public snakePriceOne;
uint256 public snakePriceCeiling;
uint256 public seigniorageSaved;
uint256[] public supplyTiers;
uint256[] public maxExpansionTiers;
uint256 public maxSupplyExpansionPercent;
uint256 public bondDepletionFloorPercent;
uint256 public seigniorageExpansionFloorPercent;
uint256 public maxSupplyContractionPercent;
uint256 public maxDebtRatioPercent;
// 14 first epochs (0.5 week) with 4.5% expansion regardless of SNAKE price
uint256 public bootstrapEpochs;
uint256 public bootstrapSupplyExpansionPercent;
/* =================== Added variables =================== */
uint256 public previousEpochSnakePrice;
uint256 public maxDiscountRate; // when purchasing bond
uint256 public maxPremiumRate; // when redeeming bond
uint256 public discountPercent;
uint256 public premiumThreshold;
uint256 public premiumPercent;
uint256 public mintingFactorForPayingDebt; // print extra SNAKE during debt phase
address public daoFund;
uint256 public daoFundSharedPercent;
//=================================================//
address public devFund;
uint256 public devFundSharedPercent;
address public teamFund;
uint256 public teamFundSharedPercent;
/* =================== Events =================== */
event Initialized(address indexed executor, uint256 at);
event BurnedBonds(address indexed from, uint256 bondAmount);
event RedeemedBonds(address indexed from, uint256 snakeAmount, uint256 bondAmount);
event BoughtBonds(address indexed from, uint256 snakeAmount, uint256 bondAmount);
event TreasuryFunded(uint256 timestamp, uint256 seigniorage);
event MasonryFunded(uint256 timestamp, uint256 seigniorage);
event DaoFundFunded(uint256 timestamp, uint256 seigniorage);
event DevFundFunded(uint256 timestamp, uint256 seigniorage);
event TeamFundFunded(uint256 timestamp, uint256 seigniorage);
/* =================== Modifier =================== */
modifier checkCondition {
require(block.timestamp >= startTime, "Treasury: not started yet");
_;
}
modifier checkEpoch {
require(block.timestamp >= nextEpochPoint(), "Treasury: not opened yet");
_;
epoch = epoch.add(1);
epochSupplyContractionLeft = (getSnakePrice() > snakePriceCeiling) ? 0 : getSnakeCirculatingSupply().mul(maxSupplyContractionPercent).div(10000);
}
modifier checkOperator {
require(
IBasisAsset(snake).operator() == address(this) &&
IBasisAsset(bsnake).operator() == address(this) &&
IBasisAsset(gsnake).operator() == address(this) &&
Operator(masonry).operator() == address(this),
"Treasury: need more permission"
);
_;
}
modifier notInitialized {
require(!initialized, "Treasury: already initialized");
_;
}
/* ========== VIEW FUNCTIONS ========== */
function isInitialized() public view returns (bool) {
return initialized;
}
// epoch
function nextEpochPoint() public view returns (uint256) {
return startTime.add(epoch.mul(PERIOD));
}
// oracle
function getSnakePrice() public view returns (uint256 snakePrice) {
try IOracle(snakeOracle).consult(snake, 1e18) returns (uint256 price) {
return uint256(price);
} catch {
revert("Treasury: failed to consult SNAKE price from the oracle");
}
}
function getSnakeUpdatedPrice() public view returns (uint256 _snakePrice) {
try IOracle(snakeOracle).twap(snake, 1e18) returns (uint256 price) {
return uint256(price);
} catch {
revert("Treasury: failed to consult SNAKE price from the oracle");
}
}
// budget
function getReserve() public view returns (uint256) {
return seigniorageSaved;
}
function getBurnableSnakeLeft() public view returns (uint256 _burnableSnakeLeft) {
uint256 _snakePrice = getSnakePrice();
if (_snakePrice <= snakePriceOne) {
uint256 _snakeSupply = getSnakeCirculatingSupply();
uint256 _bondMaxSupply = _snakeSupply.mul(maxDebtRatioPercent).div(10000);
uint256 _bondSupply = IERC20(bsnake).totalSupply();
if (_bondMaxSupply > _bondSupply) {
uint256 _maxMintableBond = _bondMaxSupply.sub(_bondSupply);
uint256 _maxBurnableSnake = _maxMintableBond.mul(_snakePrice).div(1e18);
_burnableSnakeLeft = Math.min(epochSupplyContractionLeft, _maxBurnableSnake);
}
}
}
function getRedeemableBonds() public view returns (uint256 _redeemableBonds) {
uint256 _snakePrice = getSnakePrice();
if (_snakePrice > snakePriceCeiling) {
uint256 _totalSnake = IERC20(snake).balanceOf(address(this));
uint256 _rate = getBondPremiumRate();
if (_rate > 0) {
_redeemableBonds = _totalSnake.mul(1e18).div(_rate);
}
}
}
function getBondDiscountRate() public view returns (uint256 _rate) {
uint256 _snakePrice = getSnakePrice();
if (_snakePrice <= snakePriceOne) {
if (discountPercent == 0) {
// no discount
_rate = snakePriceOne;
} else {
uint256 _bondAmount = snakePriceOne.mul(1e18).div(_snakePrice); // to burn 1 SNAKE
uint256 _discountAmount = _bondAmount.sub(snakePriceOne).mul(discountPercent).div(10000);
_rate = snakePriceOne.add(_discountAmount);
if (maxDiscountRate > 0 && _rate > maxDiscountRate) {
_rate = maxDiscountRate;
}
}
}
}
function getBondPremiumRate() public view returns (uint256 _rate) {
uint256 _snakePrice = getSnakePrice();
if (_snakePrice > snakePriceCeiling) {
uint256 _snakePricePremiumThreshold = snakePriceOne.mul(premiumThreshold).div(100);
if (_snakePrice >= _snakePricePremiumThreshold) {
//Price > 1.10
uint256 _premiumAmount = _snakePrice.sub(snakePriceOne).mul(premiumPercent).div(10000);
_rate = snakePriceOne.add(_premiumAmount);
if (maxPremiumRate > 0 && _rate > maxPremiumRate) {
_rate = maxPremiumRate;
}
} else {
// no premium bonus
_rate = snakePriceOne;
}
}
}
/* ========== GOVERNANCE ========== */
function initialize(
address _snake,
address _bsnake,
address _gsnake,
address _snakeOracle,
address _masonry,
uint256 _startTime
) public notInitialized onlyOperator {
snake = _snake;
bsnake = _bsnake;
gsnake = _gsnake;
snakeOracle = _snakeOracle;
masonry = _masonry;
startTime = _startTime;
snakePriceOne = 10 ** 18;
snakePriceCeiling = 1000300000000000000; // 1.003 as its stable pool
// snakePriceCeiling = snakePriceOne.mul(101).div(100);
// Dynamic max expansion percent
supplyTiers = [0 ether, 500000 ether, 750000 ether, 1000000 ether, 1200000 ether, 1500000 ether, 2000000 ether];
maxExpansionTiers = [100, 90, 80, 70, 60, 50, 20];
maxSupplyExpansionPercent = 150; // Upto 1.5% supply for expansion
bondDepletionFloorPercent = 10000; // 100% of Bond supply for depletion floor
seigniorageExpansionFloorPercent = 3500; // At least 35% of expansion reserved for masonry
maxSupplyContractionPercent = 1000; // Upto 10.0% supply for contraction (to burn SNAKE and mint bsnake)
maxDebtRatioPercent = 3500; // Upto 35% supply of bsnake to purchase
premiumThreshold = 110;
premiumPercent = 7000;
// First 12 epochs with 1.5% expansion
bootstrapEpochs = 12;
bootstrapSupplyExpansionPercent = 150;
// set seigniorageSaved to it's balance
seigniorageSaved = IERC20(snake).balanceOf(address(this));
initialized = true;
emit Initialized(msg.sender, block.number);
}
function setOperator(address _operator) external onlyOperator {
transferOperator(_operator);
}
function renounceOperator() external onlyOperator {
_renounceOperator();
}
function setMasonry(address _masonry) external onlyOperator {
masonry = _masonry;
}
function setSnakeOracle(address _snakeOracle) external onlyOperator {
snakeOracle = _snakeOracle;
}
function setSnakePriceCeiling(uint256 _snakePriceCeiling) external onlyOperator {
require(_snakePriceCeiling >= snakePriceOne && _snakePriceCeiling <= snakePriceOne.mul(120).div(100), "out of range"); // [$1.0, $1.2]
snakePriceCeiling = _snakePriceCeiling;
}
function setMaxSupplyExpansionPercents(uint256 _maxSupplyExpansionPercent) external onlyOperator {
require(_maxSupplyExpansionPercent >= 10 && _maxSupplyExpansionPercent <= 1000, "_maxSupplyExpansionPercent: out of range"); // [0.1%, 10%]
maxSupplyExpansionPercent = _maxSupplyExpansionPercent;
}
// =================== ALTER THE NUMBERS IN LOGIC!!!! =================== //
function setSupplyTiersEntry(uint8 _index, uint256 _value) external onlyOperator returns (bool) {
require(_index >= 0, "Index has to be higher than 0");
require(_index < 7, "Index has to be lower than count of tiers");
if (_index > 0) {
require(_value > supplyTiers[_index - 1]);
}
if (_index < 6) {
require(_value < supplyTiers[_index + 1]);
}
supplyTiers[_index] = _value;
return true;
}
function setMaxExpansionTiersEntry(uint8 _index, uint256 _value) external onlyOperator returns (bool) {
require(_index >= 0, "Index has to be higher than 0");
require(_index < 7, "Index has to be lower than count of tiers");
require(_value >= 10 && _value <= 1000, "_value: out of range"); // [0.1%, 10%]
maxExpansionTiers[_index] = _value;
return true;
}
function setBondDepletionFloorPercent(uint256 _bondDepletionFloorPercent) external onlyOperator {
require(_bondDepletionFloorPercent >= 500 && _bondDepletionFloorPercent <= 10000, "out of range"); // [5%, 100%]
bondDepletionFloorPercent = _bondDepletionFloorPercent;
}
function setMaxSupplyContractionPercent(uint256 _maxSupplyContractionPercent) external onlyOperator {
require(_maxSupplyContractionPercent >= 100 && _maxSupplyContractionPercent <= 1500, "out of range"); // [0.1%, 15%]
maxSupplyContractionPercent = _maxSupplyContractionPercent;
}
function setMaxDebtRatioPercent(uint256 _maxDebtRatioPercent) external onlyOperator {
require(_maxDebtRatioPercent >= 1000 && _maxDebtRatioPercent <= 10000, "out of range"); // [10%, 100%]
maxDebtRatioPercent = _maxDebtRatioPercent;
}
function setBootstrap(uint256 _bootstrapEpochs, uint256 _bootstrapSupplyExpansionPercent) external onlyOperator {
require(_bootstrapEpochs <= 120, "_bootstrapEpochs: out of range"); // <= 1 month
require(_bootstrapSupplyExpansionPercent >= 100 && _bootstrapSupplyExpansionPercent <= 1000, "_bootstrapSupplyExpansionPercent: out of range"); // [1%, 10%]
bootstrapEpochs = _bootstrapEpochs;
bootstrapSupplyExpansionPercent = _bootstrapSupplyExpansionPercent;
}
//======================================================================
function setExtraFunds(
address _daoFund,
uint256 _daoFundSharedPercent,
address _devFund,
uint256 _devFundSharedPercent,
address _teamFund,
uint256 _teamFundSharedPercent
) external onlyOperator {
require(_daoFund != address(0), "zero");
require(_daoFundSharedPercent <= 1500, "out of range");
require(_devFund != address(0), "zero");
require(_devFundSharedPercent <= 350, "out of range");
require(_teamFund != address(0), "zero");
require(_teamFundSharedPercent <= 550, "out of range");
daoFund = _daoFund;
daoFundSharedPercent = _daoFundSharedPercent;
devFund = _devFund;
devFundSharedPercent = _devFundSharedPercent;
teamFund = _teamFund;
teamFundSharedPercent = _teamFundSharedPercent;
}
function setMaxDiscountRate(uint256 _maxDiscountRate) external onlyOperator {
require(_maxDiscountRate <= 20000, "_maxDiscountRate is over 200%");
maxDiscountRate = _maxDiscountRate;
}
function setMaxPremiumRate(uint256 _maxPremiumRate) external onlyOperator {
require(_maxPremiumRate <= 20000, "_maxPremiumRate is over 200%");
maxPremiumRate = _maxPremiumRate;
}
function setDiscountPercent(uint256 _discountPercent) external onlyOperator {
require(_discountPercent <= 20000, "_discountPercent is over 200%");
discountPercent = _discountPercent;
}
function setPremiumThreshold(uint256 _premiumThreshold) external onlyOperator {
require(_premiumThreshold >= snakePriceCeiling, "_premiumThreshold exceeds snakePriceCeiling");
require(_premiumThreshold <= 150, "_premiumThreshold is higher than 1.5");
premiumThreshold = _premiumThreshold;
}
function setPremiumPercent(uint256 _premiumPercent) external onlyOperator {
require(_premiumPercent <= 20000, "_premiumPercent is over 200%");
premiumPercent = _premiumPercent;
}
function setMintingFactorForPayingDebt(uint256 _mintingFactorForPayingDebt) external onlyOperator {
require(_mintingFactorForPayingDebt >= 10000 && _mintingFactorForPayingDebt <= 20000, "_mintingFactorForPayingDebt: out of range"); // [100%, 200%]
mintingFactorForPayingDebt = _mintingFactorForPayingDebt;
}
/* ========== MUTABLE FUNCTIONS ========== */
function _updateSnakePrice() internal {
try IOracle(snakeOracle).update() {} catch {}
}
function getSnakeCirculatingSupply() public view returns (uint256) {
IERC20 snakeErc20 = IERC20(snake);
uint256 totalSupply = snakeErc20.totalSupply();
uint256 balanceExcluded = 0;
for (uint8 entryId = 0; entryId < excludedFromTotalSupply.length; ++entryId) {
balanceExcluded = balanceExcluded.add(snakeErc20.balanceOf(excludedFromTotalSupply[entryId]));
}
return totalSupply.sub(balanceExcluded);
}
function buyBonds(uint256 _snakeAmount, uint256 targetPrice) external onlyOneBlock checkCondition checkOperator {
require(_snakeAmount > 0, "Treasury: cannot purchase bonds with zero amount");
uint256 snakePrice = getSnakePrice();
require(snakePrice == targetPrice, "Treasury: SNAKE price moved");
require(
snakePrice < snakePriceOne, // price < $1
"Treasury: snakePrice not eligible for bond purchase"
);
require(_snakeAmount <= epochSupplyContractionLeft, "Treasury: not enough bond left to purchase");
uint256 _rate = getBondDiscountRate();
require(_rate > 0, "Treasury: invalid bond rate");
uint256 _bondAmount = _snakeAmount.mul(_rate).div(1e18);
uint256 snakeSupply = getSnakeCirculatingSupply();
uint256 newBondSupply = IERC20(bsnake).totalSupply().add(_bondAmount);
require(newBondSupply <= snakeSupply.mul(maxDebtRatioPercent).div(10000), "over max debt ratio");
IBasisAsset(snake).burnFrom(msg.sender, _snakeAmount);
IBasisAsset(bsnake).mint(msg.sender, _bondAmount);
epochSupplyContractionLeft = epochSupplyContractionLeft.sub(_snakeAmount);
_updateSnakePrice();
emit BoughtBonds(msg.sender, _snakeAmount, _bondAmount);
}
function redeemBonds(uint256 _bondAmount, uint256 targetPrice) external onlyOneBlock checkCondition checkOperator {
require(_bondAmount > 0, "Treasury: cannot redeem bonds with zero amount");
uint256 snakePrice = getSnakePrice();
require(snakePrice == targetPrice, "Treasury: SNAKE price moved");
require(
snakePrice > snakePriceCeiling, // price > $1.01
"Treasury: snakePrice not eligible for bond purchase"
);
uint256 _rate = getBondPremiumRate();
require(_rate > 0, "Treasury: invalid bond rate");
uint256 _snakeAmount = _bondAmount.mul(_rate).div(1e18);
require(IERC20(snake).balanceOf(address(this)) >= _snakeAmount, "Treasury: treasury has no more budget");
seigniorageSaved = seigniorageSaved.sub(Math.min(seigniorageSaved, _snakeAmount));
IBasisAsset(bsnake).burnFrom(msg.sender, _bondAmount);
IERC20(snake).safeTransfer(msg.sender, _snakeAmount);
_updateSnakePrice();
emit RedeemedBonds(msg.sender, _snakeAmount, _bondAmount);
}
function _sendToMasonry(uint256 _amount) internal {
IBasisAsset(snake).mint(address(this), _amount);
uint256 _daoFundSharedAmount = 0;
if (daoFundSharedPercent > 0) {
_daoFundSharedAmount = _amount.mul(daoFundSharedPercent).div(10000);
IERC20(snake).transfer(daoFund, _daoFundSharedAmount);
emit DaoFundFunded(block.timestamp, _daoFundSharedAmount);
}
uint256 _devFundSharedAmount = 0;
if (devFundSharedPercent > 0) {
_devFundSharedAmount = _amount.mul(devFundSharedPercent).div(10000);
IERC20(snake).transfer(devFund, _devFundSharedAmount);
emit DevFundFunded(block.timestamp, _devFundSharedAmount);
}
uint256 _teamFundSharedAmount = 0;
if (teamFundSharedPercent > 0) {
_teamFundSharedAmount = _amount.mul(teamFundSharedPercent).div(10000);
IERC20(snake).transfer(teamFund, _teamFundSharedAmount);
emit TeamFundFunded(block.timestamp, _teamFundSharedAmount);
}
_amount = _amount.sub(_daoFundSharedAmount).sub(_devFundSharedAmount).sub(_teamFundSharedAmount);
IERC20(snake).safeApprove(masonry, 0);
IERC20(snake).safeApprove(masonry, _amount);
IMasonry(masonry).allocateSeigniorage(_amount);
emit MasonryFunded(block.timestamp, _amount);
}
function _calculateMaxSupplyExpansionPercent(uint256 _snakeSupply) internal returns (uint256) {
for (uint8 tierId = 6; tierId >= 0; --tierId) {
if (_snakeSupply >= supplyTiers[tierId]) {
maxSupplyExpansionPercent = maxExpansionTiers[tierId];
break;
}
}
return maxSupplyExpansionPercent;
}
function allocateSeigniorage() external onlyOneBlock checkCondition checkEpoch checkOperator {
_updateSnakePrice();
previousEpochSnakePrice = getSnakePrice();
uint256 snakeSupply = getSnakeCirculatingSupply().sub(seigniorageSaved);
if (epoch < bootstrapEpochs) {
// 14 first epochs with 6% expansion
_sendToMasonry(snakeSupply.mul(bootstrapSupplyExpansionPercent).div(10000));
} else {
if (previousEpochSnakePrice > snakePriceCeiling) {
// Expansion ($SNAKE Price > 1 $FTM): there is some seigniorage to be allocated
uint256 bondSupply = IERC20(bsnake).totalSupply();
uint256 _percentage = previousEpochSnakePrice.sub(snakePriceOne);
uint256 _savedForBond;
uint256 _savedForMasonry;
uint256 _mse = _calculateMaxSupplyExpansionPercent(snakeSupply).mul(1e14);
if (_percentage > _mse) {
_percentage = _mse;
}
if (seigniorageSaved >= bondSupply.mul(bondDepletionFloorPercent).div(10000)) {
// saved enough to pay debt, mint as usual rate
_savedForMasonry = snakeSupply.mul(_percentage).div(1e18);
} else {
// have not saved enough to pay debt, mint more
uint256 _seigniorage = snakeSupply.mul(_percentage).div(1e18);
_savedForMasonry = _seigniorage.mul(seigniorageExpansionFloorPercent).div(10000);
_savedForBond = _seigniorage.sub(_savedForMasonry);
if (mintingFactorForPayingDebt > 0) {
_savedForBond = _savedForBond.mul(mintingFactorForPayingDebt).div(10000);
}
}
if (_savedForMasonry > 0) {
_sendToMasonry(_savedForMasonry);
}
if (_savedForBond > 0) {
seigniorageSaved = seigniorageSaved.add(_savedForBond);
IBasisAsset(snake).mint(address(this), _savedForBond);
emit TreasuryFunded(block.timestamp, _savedForBond);
}
}
}
}
//===================================================================================================================================
function governanceRecoverUnsupported(
IERC20 _token,
uint256 _amount,
address _to
) external onlyOperator {
// do not allow to drain core tokens
require(address(_token) != address(snake), "snake");
require(address(_token) != address(bsnake), "bond");
require(address(_token) != address(gsnake), "share");
_token.safeTransfer(_to, _amount);
}
function masonrySetOperator(address _operator) external onlyOperator {
IMasonry(masonry).setOperator(_operator);
}
function masonrySetLockUp(uint256 _withdrawLockupEpochs, uint256 _rewardLockupEpochs) external onlyOperator {
IMasonry(masonry).setLockUp(_withdrawLockupEpochs, _rewardLockupEpochs);
}
function masonryAllocateSeigniorage(uint256 amount) external onlyOperator {
IMasonry(masonry).allocateSeigniorage(amount);
}
function masonryGovernanceRecoverUnsupported(
address _token,
uint256 _amount,
address _to
) external onlyOperator {
IMasonry(masonry).governanceRecoverUnsupported(_token, _amount, _to);
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
contract ContractGuard {
mapping(uint256 => mapping(address => bool)) private _status;
function checkSameOriginReentranted() internal view returns (bool) {
return _status[block.number][tx.origin];
}
function checkSameSenderReentranted() internal view returns (bool) {
return _status[block.number][msg.sender];
}
modifier onlyOneBlock() {
require(!checkSameOriginReentranted(), "ContractGuard: one block, one function");
require(!checkSameSenderReentranted(), "ContractGuard: one block, one function");
_;
_status[block.number][tx.origin] = true;
_status[block.number][msg.sender] = true;
}
}