Contract Name:
StableConvexXPool
Contract Source Code:
File 1 of 1 : StableConvexXPool
// SPDX-License-Identifier: MIT AND GPL-3.0 AND AGPLv3
// File: @openzeppelin/contracts/token/ERC20/IERC20.sol
pragma solidity ^0.8.0;
/**
* @dev Interface of the ERC20 standard as defined in the EIP.
*/
interface IERC20 {
/**
* @dev Returns the amount of tokens in existence.
*/
function totalSupply() external view returns (uint256);
/**
* @dev Returns the amount of tokens owned by `account`.
*/
function balanceOf(address account) external view returns (uint256);
/**
* @dev Moves `amount` tokens from the caller's account to `recipient`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transfer(address recipient, uint256 amount) external returns (bool);
/**
* @dev Returns the remaining number of tokens that `spender` will be
* allowed to spend on behalf of `owner` through {transferFrom}. This is
* zero by default.
*
* This value changes when {approve} or {transferFrom} are called.
*/
function allowance(address owner, address spender) external view returns (uint256);
/**
* @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* IMPORTANT: Beware that changing an allowance with this method brings the risk
* that someone may use both the old and the new allowance by unfortunate
* transaction ordering. One possible solution to mitigate this race
* condition is to first reduce the spender's allowance to 0 and set the
* desired value afterwards:
* https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
*
* Emits an {Approval} event.
*/
function approve(address spender, uint256 amount) external returns (bool);
/**
* @dev Moves `amount` tokens from `sender` to `recipient` using the
* allowance mechanism. `amount` is then deducted from the caller's
* allowance.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transferFrom(
address sender,
address recipient,
uint256 amount
) external returns (bool);
/**
* @dev Emitted when `value` tokens are moved from one account (`from`) to
* another (`to`).
*
* Note that `value` may be zero.
*/
event Transfer(address indexed from, address indexed to, uint256 value);
/**
* @dev Emitted when the allowance of a `spender` for an `owner` is set by
* a call to {approve}. `value` is the new allowance.
*/
event Approval(address indexed owner, address indexed spender, uint256 value);
}
// File: openzeppelin/contracts/utils/Address.sol
pragma solidity ^0.8.0;
/**
* @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
* ====
*/
function isContract(address account) internal view returns (bool) {
// This method relies on extcodesize, which returns 0 for contracts in
// construction, since the code is only stored at the end of the
// constructor execution.
uint256 size;
// solhint-disable-next-line no-inline-assembly
assembly { size := extcodesize(account) }
return size > 0;
}
/**
* @dev Replacement for Solidity's `transfer`: sends `amount` wei to
* `recipient`, forwarding all available gas and reverting on errors.
*
* https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
* of certain opcodes, possibly making contracts go over the 2300 gas limit
* imposed by `transfer`, making them unable to receive funds via
* `transfer`. {sendValue} removes this limitation.
*
* https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
*
* IMPORTANT: because control is transferred to `recipient`, care must be
* taken to not create reentrancy vulnerabilities. Consider using
* {ReentrancyGuard} or the
* https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
*/
function sendValue(address payable recipient, uint256 amount) internal {
require(address(this).balance >= amount, "Address: insufficient balance");
// solhint-disable-next-line avoid-low-level-calls, avoid-call-value
(bool success, ) = recipient.call{ value: amount }("");
require(success, "Address: unable to send value, recipient may have reverted");
}
/**
* @dev Performs a Solidity function call using a low level `call`. A
* plain`call` is an unsafe replacement for a function call: use this
* function instead.
*
* If `target` reverts with a revert reason, it is bubbled up by this
* function (like regular Solidity function calls).
*
* Returns the raw returned data. To convert to the expected return value,
* use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
*
* Requirements:
*
* - `target` must be a contract.
* - calling `target` with `data` must not revert.
*
* _Available since v3.1._
*/
function functionCall(address target, bytes memory data) internal returns (bytes memory) {
return functionCall(target, data, "Address: low-level call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
* `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
return functionCallWithValue(target, data, 0, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but also transferring `value` wei to `target`.
*
* Requirements:
*
* - the calling contract must have an ETH balance of at least `value`.
* - the called Solidity function must be `payable`.
*
* _Available since v3.1._
*/
function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
}
/**
* @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
* with `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
require(address(this).balance >= value, "Address: insufficient balance for call");
require(isContract(target), "Address: call to non-contract");
// solhint-disable-next-line avoid-low-level-calls
(bool success, bytes memory returndata) = target.call{ value: value }(data);
return _verifyCallResult(success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
return functionStaticCall(target, data, "Address: low-level static call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {
require(isContract(target), "Address: static call to non-contract");
// solhint-disable-next-line avoid-low-level-calls
(bool success, bytes memory returndata) = target.staticcall(data);
return _verifyCallResult(success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a delegate call.
*
* _Available since v3.4._
*/
function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
return functionDelegateCall(target, data, "Address: low-level delegate call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a delegate call.
*
* _Available since v3.4._
*/
function functionDelegateCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
require(isContract(target), "Address: delegate call to non-contract");
// solhint-disable-next-line avoid-low-level-calls
(bool success, bytes memory returndata) = target.delegatecall(data);
return _verifyCallResult(success, returndata, errorMessage);
}
function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
if (success) {
return returndata;
} else {
// Look for revert reason and bubble it up if present
if (returndata.length > 0) {
// The easiest way to bubble the revert reason is using memory via assembly
// solhint-disable-next-line no-inline-assembly
assembly {
let returndata_size := mload(returndata)
revert(add(32, returndata), returndata_size)
}
} else {
revert(errorMessage);
}
}
}
}
// File: openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol
pragma solidity ^0.8.0;
/**
* @title SafeERC20
* @dev Wrappers around ERC20 operations that throw on failure (when the token
* contract returns false). Tokens that return no value (and instead revert or
* throw on failure) are also supported, non-reverting calls are assumed to be
* successful.
* To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
* which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
*/
library SafeERC20 {
using Address for address;
function safeTransfer(IERC20 token, address to, uint256 value) internal {
_callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
}
function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
_callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
}
/**
* @dev Deprecated. This function has issues similar to the ones found in
* {IERC20-approve}, and its usage is discouraged.
*
* Whenever possible, use {safeIncreaseAllowance} and
* {safeDecreaseAllowance} instead.
*/
function safeApprove(IERC20 token, address spender, uint256 value) internal {
// safeApprove should only be called when setting an initial allowance,
// or when resetting it to zero. To increase and decrease it, use
// 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
// solhint-disable-next-line max-line-length
require((value == 0) || (token.allowance(address(this), spender) == 0),
"SafeERC20: approve from non-zero to non-zero allowance"
);
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
}
function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
uint256 newAllowance = token.allowance(address(this), spender) + value;
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
}
function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
unchecked {
uint256 oldAllowance = token.allowance(address(this), spender);
require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
uint256 newAllowance = oldAllowance - value;
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
}
}
/**
* @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
* on the return value: the return value is optional (but if data is returned, it must not be false).
* @param token The token targeted by the call.
* @param data The call data (encoded using abi.encode or one of its variants).
*/
function _callOptionalReturn(IERC20 token, bytes memory data) private {
// We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
// we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
// the target address contains contract code and also asserts for success in the low-level call.
bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
if (returndata.length > 0) { // Return data is optional
// solhint-disable-next-line max-line-length
require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
}
}
}
// File: contracts/BaseStrategy.sol
pragma solidity 0.8.4;
struct StrategyParams {
uint256 activation;
uint256 debtRatio;
uint256 minDebtPerHarvest;
uint256 maxDebtPerHarvest;
uint256 lastReport;
uint256 totalDebt;
uint256 totalGain;
uint256 totalLoss;
}
interface VaultAPI {
function decimals() external view returns (uint256);
function token() external view returns (address);
function vaultAdapter() external view returns (address);
function strategies(address _strategy) external view returns (StrategyParams memory);
/**
* View how much the Vault would increase this Strategy's borrow limit,
* based on its present performance (since its last report). Can be used to
* determine expectedReturn in your Strategy.
*/
function creditAvailable() external view returns (uint256);
/**
* View how much the Vault would like to pull back from the Strategy,
* based on its present performance (since its last report). Can be used to
* determine expectedReturn in your Strategy.
*/
function debtOutstanding() external view returns (uint256);
/**
* View how much the Vault expect this Strategy to return at the current
* block, based on its present performance (since its last report). Can be
* used to determine expectedReturn in your Strategy.
*/
function expectedReturn() external view returns (uint256);
/**
* This is the main contact point where the Strategy interacts with the
* Vault. It is critical that this call is handled as intended by the
* Strategy. Therefore, this function will be called by BaseStrategy to
* make sure the integration is correct.
*/
function report(
uint256 _gain,
uint256 _loss,
uint256 _debtPayment
) external returns (uint256);
/**
* This function should only be used in the scenario where the Strategy is
* being retired but no migration of the positions are possible, or in the
* extreme scenario that the Strategy needs to be put into "Emergency Exit"
* mode in order for it to exit as quickly as possible. The latter scenario
* could be for any reason that is considered "critical" that the Strategy
* exits its position as fast as possible, such as a sudden change in
* market conditions leading to losses, or an imminent failure in an
* external dependency.
*/
function revokeStrategy() external;
function governance() external view returns (address);
}
/**
* This interface is here for the keeper bot to use.
*/
interface StrategyAPI {
function name() external view returns (string memory);
function vault() external view returns (address);
function want() external view returns (address);
function keeper() external view returns (address);
function isActive() external view returns (bool);
function estimatedTotalAssets() external view returns (uint256);
function expectedReturn() external view returns (uint256);
function tendTrigger(uint256 callCost) external view returns (bool);
function tend() external;
function harvestTrigger(uint256 callCost) external view returns (bool);
function harvest() external;
event Harvested(uint256 profit, uint256 loss, uint256 debtPayment, uint256 debtOutstanding);
}
/**
* @title Yearn Base Strategy
* @author orig. yearn.finance, modified by gro-protocol
* @notice
* BaseStrategy implements all of the required functionality to interoperate
* closely with the Vault contract. This contract should be inherited and the
* abstract methods implemented to adapt the Strategy to the particular needs
* it has to create a return.
*
* Of special interest is the relationship between `harvest()` and
* `vault.report()'. `harvest()` may be called simply because enough time has
* elapsed since the last report, and not because any funds need to be moved
* or positions adjusted. This is critical so that the Vault may maintain an
* accurate picture of the Strategy's performance. See `vault.report()`,
* `harvest()`, and `harvestTrigger()` for further details.
*/
abstract contract BaseStrategy {
using SafeERC20 for IERC20;
VaultAPI public vault;
address public rewards;
address public keeper;
IERC20 public want;
// So indexers can keep track of this
event Harvested(uint256 profit, uint256 loss, uint256 debtPayment, uint256 debtOutstanding);
event UpdatedKeeper(address newKeeper);
event UpdatedRewards(address rewards);
event UpdatedMinReportDelay(uint256 delay);
event UpdatedMaxReportDelay(uint256 delay);
event UpdatedProfitFactor(uint256 profitFactor);
event UpdatedDebtThreshold(uint256 debtThreshold);
event EmergencyExitEnabled();
// The minimum number of seconds between harvest calls. See
// `setMinReportDelay()` for more details.
uint256 public minReportDelay;
// The maximum number of seconds between harvest calls. See
// `setMaxReportDelay()` for more details.
uint256 public maxReportDelay;
// The minimum multiple that `callCost` must be above the credit/profit to
// be "justifiable". See `setProfitFactor()` for more details.
uint256 public profitFactor;
// Use this to adjust the threshold at which running a debt causes a
// harvest trigger. See `setDebtThreshold()` for more details.
uint256 public debtThreshold;
// See note on `setEmergencyExit()`.
bool public emergencyExit;
// modifiers
modifier onlyAuthorized() {
require(msg.sender == keeper || msg.sender == owner(), "!authorized");
_;
}
modifier onlyOwner() {
require(msg.sender == owner(), "!authorized");
_;
}
constructor(address _vault) {
_initialize(_vault, msg.sender, msg.sender);
}
function name() external view virtual returns (string memory);
/**
* @notice
* Initializes the Strategy, this is called only once, when the
* contract is deployed.
* @param _vault The address of the Vault responsible for this Strategy.
*/
function _initialize(
address _vault,
address _rewards,
address _keeper
) internal {
require(address(want) == address(0), "Strategy already initialized");
vault = VaultAPI(_vault);
want = IERC20(vault.token());
want.safeApprove(_vault, type(uint256).max); // Give Vault unlimited access (might save gas)
rewards = _rewards;
keeper = _keeper;
// initialize variables
minReportDelay = 0;
maxReportDelay = 86400;
profitFactor = 100;
debtThreshold = 0;
}
function setKeeper(address _keeper) external onlyOwner {
require(_keeper != address(0));
keeper = _keeper;
emit UpdatedKeeper(_keeper);
}
/**
* @notice
* Used to change `minReportDelay`. `minReportDelay` is the minimum number
* of blocks that should pass for `harvest()` to be called.
*
* For external keepers (such as the Keep3r network), this is the minimum
* time between jobs to wait. (see `harvestTrigger()`
* for more details.)
*
* @param _delay The minimum number of seconds to wait between harvests.
*/
function setMinReportDelay(uint256 _delay) external onlyAuthorized {
minReportDelay = _delay;
emit UpdatedMinReportDelay(_delay);
}
/**
* @notice
* Used to change `maxReportDelay`. `maxReportDelay` is the maximum number
* of blocks that should pass for `harvest()` to be called.
*
* For external keepers (such as the Keep3r network), this is the maximum
* time between jobs to wait. (see `harvestTrigger()`
* for more details.)
*
* @param _delay The maximum number of seconds to wait between harvests.
*/
function setMaxReportDelay(uint256 _delay) external onlyAuthorized {
maxReportDelay = _delay;
emit UpdatedMaxReportDelay(_delay);
}
/**
* @notice
* Used to change `profitFactor`. `profitFactor` is used to determine
* if it's worthwhile to harvest, given gas costs. (See `harvestTrigger()`
* for more details.)
*
* @param _profitFactor A ratio to multiply anticipated
* `harvest()` gas cost against.
*/
function setProfitFactor(uint256 _profitFactor) external onlyAuthorized {
profitFactor = _profitFactor;
emit UpdatedProfitFactor(_profitFactor);
}
/**
* @notice
* Sets how far the Strategy can go into loss without a harvest and report
* being required.
*
* By default this is 0, meaning any losses would cause a harvest which
* will subsequently report the loss to the Vault for tracking. (See
* `harvestTrigger()` for more details.)
*
* @param _debtThreshold How big of a loss this Strategy may carry without
* being required to report to the Vault.
*/
function setDebtThreshold(uint256 _debtThreshold) external onlyAuthorized {
debtThreshold = _debtThreshold;
emit UpdatedDebtThreshold(_debtThreshold);
}
/**
* Resolve owner address from Vault contract, used to make assertions
* on protected functions in the Strategy.
*/
function owner() internal view returns (address) {
return vault.governance();
}
/**
* @notice
* Provide an accurate estimate for the total amount of assets
* (principle + return) that this Strategy is currently managing,
* denominated in terms of `want` tokens.
*
* This total should be "realizable" e.g. the total value that could
* *actually* be obtained from this Strategy if it were to divest its
* entire position based on current on-chain conditions.
* @dev
* Care must be taken in using this function, since it relies on external
* systems, which could be manipulated by the attacker to give an inflated
* (or reduced) value produced by this function, based on current on-chain
* conditions (e.g. this function is possible to influence through
* flashloan attacks, oracle manipulations, or other DeFi attack
* mechanisms).
*
* It is up to owner to use this function to correctly order this
* Strategy relative to its peers in the withdrawal queue to minimize
* losses for the Vault based on sudden withdrawals. This value should be
* higher than the total debt of the Strategy and higher than its expected
* value to be "safe".
* @return The estimated total assets in this Strategy.
*/
function estimatedTotalAssets() public view virtual returns (uint256);
/*
* @notice
* Provide an indication of whether this strategy is currently "active"
* in that it is managing an active position, or will manage a position in
* the future. This should correlate to `harvest()` activity, so that Harvest
* events can be tracked externally by indexing agents.
* @return True if the strategy is actively managing a position.
*/
function isActive() public view returns (bool) {
return vault.strategies(address(this)).debtRatio > 0 || estimatedTotalAssets() > 0;
}
/**
* Perform any Strategy unwinding or other calls necessary to capture the
* "free return" this Strategy has generated since the last time its core
* position(s) were adjusted. Examples include unwrapping extra rewards.
* This call is only used during "normal operation" of a Strategy, and
* should be optimized to minimize losses as much as possible.
*
* This method returns any realized profits and/or realized losses
* incurred, and should return the total amounts of profits/losses/debt
* payments (in `want` tokens) for the Vault's accounting (e.g.
* `want.balanceOf(this) >= _debtPayment + _profit - _loss`).
*
* `_debtOutstanding` will be 0 if the Strategy is not past the configured
* debt limit, otherwise its value will be how far past the debt limit
* the Strategy is. The Strategy's debt limit is configured in the Vault.
*
* NOTE: `_debtPayment` should be less than or equal to `_debtOutstanding`.
* It is okay for it to be less than `_debtOutstanding`, as that
* should only used as a guide for how much is left to pay back.
* Payments should be made to minimize loss from slippage, debt,
* withdrawal fees, etc.
*
* See `vault.debtOutstanding()`.
*/
function prepareReturn(uint256 _debtOutstanding)
internal
virtual
returns (
uint256 _profit,
uint256 _loss,
uint256 _debtPayment
);
/**
* Perform any adjustments to the core position(s) of this Strategy given
* what change the Vault made in the "investable capital" available to the
* Strategy. Note that all "free capital" in the Strategy after the report
* was made is available for reinvestment. Also note that this number
* could be 0, and you should handle that scenario accordingly.
*
* See comments regarding `_debtOutstanding` on `prepareReturn()`.
*/
function adjustPosition(uint256 _debtOutstanding) internal virtual;
/**
* Liquidate up to `_amountNeeded` of `want` of this strategy's positions,
* irregardless of slippage. Any excess will be re-invested with `adjustPosition()`.
* This function should return the amount of `want` tokens made available by the
* liquidation. If there is a difference between them, `_loss` indicates whether the
* difference is due to a realized loss, or if there is some other sitution at play
* (e.g. locked funds) where the amount made available is less than what is needed.
* This function is used during emergency exit instead of `prepareReturn()` to
* liquidate all of the Strategy's positions back to the Vault.
*
* NOTE: The invariant `_liquidatedAmount + _loss <= _amountNeeded` should always be maintained
*/
function liquidatePosition(uint256 _amountNeeded)
internal
virtual
returns (uint256 _liquidatedAmount, uint256 _loss);
/**
* @notice
* Provide a signal to the keeper that `tend()` should be called. The
* keeper will provide the estimated gas cost that they would pay to call
* `tend()`, and this function should use that estimate to make a
* determination if calling it is "worth it" for the keeper. This is not
* the only consideration into issuing this trigger, for example if the
* position would be negatively affected if `tend()` is not called
* shortly, then this can return `true` even if the keeper might be
* "at a loss" (keepers are always reimbursed by Yearn).
* @dev
* `callCost` must be priced in terms of `want`.
*
* This call and `harvestTrigger()` should never return `true` at the same
* time.
* @param callCost The keeper's estimated cast cost to call `tend()`.
* @return `true` if `tend()` should be called, `false` otherwise.
*/
function tendTrigger(uint256 callCost) public view virtual returns (bool);
/**
* @notice
* Adjust the Strategy's position. The purpose of tending isn't to
* realize gains, but to maximize yield by reinvesting any returns.
*
* See comments on `adjustPosition()`.
*
*/
function tend() external onlyAuthorized {
// Don't take profits with this call, but adjust for better gains
adjustPosition(vault.debtOutstanding());
}
/**
* @notice
* Provide a signal to the keeper that `harvest()` should be called. The
* keeper will provide the estimated gas cost that they would pay to call
* `harvest()`, and this function should use that estimate to make a
* determination if calling it is "worth it" for the keeper. This is not
* the only consideration into issuing this trigger, for example if the
* position would be negatively affected if `harvest()` is not called
* shortly, then this can return `true` even if the keeper might be "at a
* loss" (keepers are always reimbursed by Yearn).
* @dev
* `callCost` must be priced in terms of `want`.
*
* This call and `tendTrigger` should never return `true` at the
* same time.
*
* See `min/maxReportDelay`, `profitFactor`, `debtThreshold`
* -controlled parameters that will influence whether this call
* returns `true` or not. These parameters will be used in conjunction
* with the parameters reported to the Vault (see `params`) to determine
* if calling `harvest()` is merited.
*
* It is expected that an external system will check `harvestTrigger()`.
* This could be a script run off a desktop or cloud bot (e.g.
* https://github.com/iearn-finance/yearn-vaults/blob/master/scripts/keep.py),
* or via an integration with the Keep3r network (e.g.
* https://github.com/Macarse/GenericKeep3rV2/blob/master/contracts/keep3r/GenericKeep3rV2.sol).
* @param callCost The keeper's estimated cast cost to call `harvest()`.
* @return `true` if `harvest()` should be called, `false` otherwise.
*/
function harvestTrigger(uint256 callCost) public view virtual returns (bool) {
StrategyParams memory params = vault.strategies(address(this));
// Should not trigger if Strategy is not activated
if (params.activation == 0) return false;
// Should not trigger if we haven't waited long enough since previous harvest
if (block.timestamp - params.lastReport < minReportDelay) return false;
// Should trigger if hasn't been called in a while
if (block.timestamp - params.lastReport >= maxReportDelay) return true;
// If some amount is owed, pay it back
// NOTE: Since debt is based on deposits, it makes sense to guard against large
// changes to the value from triggering a harvest directly through user
// behavior. This should ensure reasonable resistance to manipulation
// from user-initiated withdrawals as the outstanding debt fluctuates.
uint256 outstanding = vault.debtOutstanding();
if (outstanding > debtThreshold) return true;
// Check for profits and losses
uint256 total = estimatedTotalAssets();
// Trigger if we have a loss to report
if (total + debtThreshold < params.totalDebt) return true;
uint256 profit = 0;
if (total > params.totalDebt) profit = total - params.totalDebt; // We've earned a profit!
// Otherwise, only trigger if it "makes sense" economically (gas cost
// is <N% of value moved)
uint256 credit = vault.creditAvailable();
return (profitFactor * callCost < credit + profit);
}
/**
* @notice
* Harvests the Strategy, recognizing any profits or losses and adjusting
* the Strategy's position.
*
* In the rare case the Strategy is in emergency shutdown, this will exit
* the Strategy's position.
*
* @dev
* When `harvest()` is called, the Strategy reports to the Vault (via
* `vault.report()`), so in some cases `harvest()` must be called in order
* to take in profits, to borrow newly available funds from the Vault, or
* otherwise adjust its position. In other cases `harvest()` must be
* called to report to the Vault on the Strategy's position, especially if
* any losses have occurred.
*/
function harvest() external {
require(msg.sender == vault.vaultAdapter(), "harvest: Call from vault");
uint256 profit = 0;
uint256 loss = 0;
uint256 debtOutstanding = vault.debtOutstanding();
uint256 debtPayment = 0;
if (emergencyExit) {
// Free up as much capital as possible
uint256 totalAssets = estimatedTotalAssets();
// NOTE: use the larger of total assets or debt outstanding to book losses properly
(debtPayment, loss) = liquidatePosition(totalAssets > debtOutstanding ? totalAssets : debtOutstanding);
// NOTE: take up any remainder here as profit
if (debtPayment > debtOutstanding) {
profit = debtPayment - debtOutstanding;
debtPayment = debtOutstanding;
}
} else {
// Free up returns for Vault to pull
(profit, loss, debtPayment) = prepareReturn(debtOutstanding);
}
// Allow Vault to take up to the "harvested" balance of this contract,
// which is the amount it has earned since the last time it reported to
// the Vault.
debtOutstanding = vault.report(profit, loss, debtPayment);
// Check if free returns are left, and re-invest them
adjustPosition(debtOutstanding);
emit Harvested(profit, loss, debtPayment, debtOutstanding);
}
/**
* @notice
* Withdraws `_amountNeeded` to `vault`.
*
* This may only be called by the Vault.
* @param _amountNeeded How much `want` to withdraw.
* @return _loss Any realized losses
*/
function withdraw(uint256 _amountNeeded) external returns (uint256 _loss) {
require(msg.sender == address(vault), "!vault");
// Liquidate as much as possible to `want`, up to `_amountNeeded`
uint256 amountFreed;
(amountFreed, _loss) = liquidatePosition(_amountNeeded);
// Send it directly back (NOTE: Using `msg.sender` saves some gas here)
want.safeTransfer(msg.sender, amountFreed);
// NOTE: Reinvest anything leftover on next `tend`/`harvest`
}
/**
* Do anything necessary to prepare this Strategy for migration, such as
* transferring any reserve or LP tokens, CDPs, or other tokens or stores of
* value.
*/
function prepareMigration(address _newStrategy) internal virtual;
/**
* @notice
* Transfers all `want` from this Strategy to `_newStrategy`.
*
* This may only be called by owner or the Vault.
* @dev
* The new Strategy's Vault must be the same as this Strategy's Vault.
* @param _newStrategy The Strategy to migrate to.
*/
function migrate(address _newStrategy) external {
require(msg.sender == address(vault));
require(BaseStrategy(_newStrategy).vault() == vault);
prepareMigration(_newStrategy);
want.safeTransfer(_newStrategy, want.balanceOf(address(this)));
}
/**
* @notice
* Activates emergency exit. Once activated, the Strategy will exit its
* position upon the next harvest, depositing all funds into the Vault as
* quickly as is reasonable given on-chain conditions.
*
* @dev
* See `vault.setEmergencyShutdown()` and `harvest()` for further details.
*/
function setEmergencyExit() external onlyAuthorized {
emergencyExit = true;
vault.revokeStrategy();
emit EmergencyExitEnabled();
}
/**
* Override this to add all tokens/tokenized positions this contract
* manages on a *persistent* basis (e.g. not just for swapping back to
* want ephemerally).
*
* NOTE: Do *not* include `want`, already included in `sweep` below.
*
* Example:
*
* function protectedTokens() internal override view returns (address[] memory) {
* address[] memory protected = new address[](3);
* protected[0] = tokenA;
* protected[1] = tokenB;
* protected[2] = tokenC;
* return protected;
* }
*/
function protectedTokens() internal view virtual returns (address[] memory);
/**
* @notice
* Removes tokens from this Strategy that are not the type of tokens
* managed by this Strategy. This may be used in case of accidentally
* sending the wrong kind of token to this Strategy.
*
* Tokens will be sent to `owner()`.
*
* This will fail if an attempt is made to sweep `want`, or any tokens
* that are protected by this Strategy.
*
* This may only be called by owner.
* @dev
* Implement `protectedTokens()` to specify any additional tokens that
* should be protected from sweeping in addition to `want`.
* @param _token The token to transfer out of this vault.
*/
function sweep(address _token) external onlyOwner {
require(_token != address(want), "!want");
require(_token != address(vault), "!shares");
address[] memory _protectedTokens = protectedTokens();
for (uint256 i; i < _protectedTokens.length; i++) require(_token != _protectedTokens[i], "!protected");
IERC20(_token).safeTransfer(owner(), IERC20(_token).balanceOf(address(this)));
}
}
// File: contracts/interfaces/IERC20Detailed.sol
pragma solidity 0.8.4;
interface IERC20Detailed {
function name() external view returns (string memory);
function symbol() external view returns (string memory);
function decimals() external view returns (uint8);
}
// File: contracts/interfaces/ICurve.sol
pragma solidity 0.8.4;
interface ICurve3Pool {
function coins(uint256 i) external view returns (address);
function get_virtual_price() external view returns (uint256);
function get_dy(
int128 i,
int128 j,
uint256 dx
) external view returns (uint256);
function calc_withdraw_one_coin(uint256 _token_amount, int128 i) external view returns (uint256);
function calc_token_amount(uint256[3] calldata inAmounts, bool deposit) external view returns (uint256);
function balances(uint256 i) external view returns (uint256);
}
interface ICurve3Deposit {
function exchange(
int128 i,
int128 j,
uint256 dx,
uint256 min_dy
) external;
function add_liquidity(uint256[3] calldata uamounts, uint256 min_mint_amount) external;
function remove_liquidity(uint256 amount, uint256[3] calldata min_uamounts) external;
function remove_liquidity_imbalance(uint256[3] calldata amounts, uint256 max_burn_amount) external;
function remove_liquidity_one_coin(
uint256 _token_amount,
int128 i,
uint256 min_uamount
) external;
function get_dy(
int128 i,
int128 j,
uint256 dx
) external view returns (uint256);
}
interface ICurveMetaPool {
function coins(uint256 i) external view returns (address);
function get_virtual_price() external view returns (uint256);
function get_dy_underlying(
int128 i,
int128 j,
uint256 dx
) external view returns (uint256);
function calc_withdraw_one_coin(uint256 _token_amount, int128 i) external view returns (uint256);
function calc_token_amount(uint256[2] calldata inAmounts, bool deposit) external view returns (uint256);
function exchange(
int128 i,
int128 j,
uint256 dx,
uint256 min_dy
) external;
function add_liquidity(uint256[2] calldata uamounts, uint256 min_mint_amount) external;
function remove_liquidity_one_coin(
uint256 _token_amount,
int128 i,
uint256 min_uamount
) external;
}
interface ICurveZap {
function add_liquidity(uint256[4] calldata uamounts, uint256 min_mint_amount) external;
function remove_liquidity(uint256 amount, uint256[4] calldata min_uamounts) external;
function remove_liquidity_imbalance(uint256[4] calldata amounts, uint256 max_burn_amount) external;
function remove_liquidity_one_coin(
uint256 _token_amount,
int128 i,
uint256 min_uamount
) external;
function calc_withdraw_one_coin(uint256 _token_amount, int128 i) external view returns (uint256);
function calc_token_amount(uint256[4] calldata inAmounts, bool deposit) external view returns (uint256);
function pool() external view returns (address);
}
// File: contracts/interfaces/UniSwap/IUni.sol
pragma solidity 0.8.4;
interface IUni {
function getAmountsOut(uint256 amountIn, address[] calldata path) external view returns (uint256[] memory amounts);
function swapExactTokensForTokens(
uint256 amountIn,
uint256 amountOutMin,
address[] calldata path,
address to,
uint256 deadline
) external returns (uint256[] memory amounts);
}
// File: @openzeppelin/contracts/utils/math/Math.sol
pragma solidity ^0.8.0;
/**
* @dev Standard math utilities missing in the Solidity language.
*/
library Math {
/**
* @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 / b + (a % b == 0 ? 0 : 1);
}
}
// File: contracts/strategies/StableConvexXPool.sol
pragma solidity 0.8.4;
/// Convex booster interface
interface Booster {
struct PoolInfo {
address lptoken;
address token;
address gauge;
address crvRewards;
address stash;
bool shutdown;
}
function poolInfo(uint256)
external
view
returns (
address,
address,
address,
address,
address,
bool
);
// deposit lp tokens and stake
function deposit(
uint256 _pid,
uint256 _amount,
bool _stake
) external returns (bool);
}
/// Convex rewards interface
interface Rewards {
function balanceOf(address account) external view returns (uint256);
function earned(address account) external view returns (uint256);
function withdrawAndUnwrap(uint256 amount, bool claim) external returns (bool);
function withdrawAllAndUnwrap(bool claim) external;
function getReward() external returns (bool);
}
/** @title StableConvexXPool
* @notice Convex strategy based of yearns convex contract that allows usage of one of the 3 pool
* stables as want, rather than a metapool lp token. This strategy can swap between meta pool
* and convex strategies to opimize yield/risk, and routes all assets through the following flow:
* 3crv => metaLp => convex.
*/
contract StableConvexXPool is BaseStrategy {
using SafeERC20 for IERC20;
/*///////////////////////////////////////////////////////////////
CONTRACT VARIABLES
//////////////////////////////////////////////////////////////*/
// Contract addresses
address public constant BOOSTER = address(0xF403C135812408BFbE8713b5A23a04b3D48AAE31);
address public constant CVX = address(0x4e3FBD56CD56c3e72c1403e103b45Db9da5B9D2B);
address public constant CRV = address(0xD533a949740bb3306d119CC777fa900bA034cd52);
address public constant WETH = address(0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2);
address public constant DAI = address(0x6B175474E89094C44Da98b954EedeAC495271d0F);
address public constant USDC = address(0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48);
address public constant USDT = address(0xdAC17F958D2ee523a2206206994597C13D831ec7);
address public constant CRV_3POOL = address(0xbEbc44782C7dB0a1A60Cb6fe97d0b483032FF1C7);
IERC20 public constant CRV_3POOL_TOKEN = IERC20(address(0x6c3F90f043a72FA612cbac8115EE7e52BDe6E490));
// Dexes for selling reward tokens
address public constant UNISWAP = address(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D);
address public constant SUSHISWAP = address(0xd9e1cE17f2641f24aE83637ab66a2cca9C378B9F);
// meta pool token layout: [minor stable, 3Crv]
int128 public constant CRV3_INDEX = 1;
uint256 public constant CRV_METAPOOL_LEN = 2;
// 3pool token layout: [dai, usdc, usdt]
uint256 public constant CRV_3POOL_LEN = 3;
uint256 public constant TO_ETH = 0;
uint256 public constant TO_WANT = 1;
// Want tokens index in 3 pool
int128 public immutable WANT_INDEX;
address public curve; // meta pool
IERC20 public lpToken; // meta pool lp token
uint256 public pId; // convex lp token pid
address public rewardContract; // convex reward contract for lp token
uint256 public newPId;
address public newCurve;
IERC20 public newLPToken;
address public newRewardContract;
address[] public dex;
uint256 constant totalCliffs = 1000;
uint256 constant maxSupply = 1e8 * 1e18;
uint256 constant reductionPerCliff = 1e5 * 1e18;
// when withdrawing we try to withdraw an additional x BP to cover withdrawal fees etc
uint256 public slippageRecover = 4;
uint256 public slippage = 10; // how much slippage to we accept
/*///////////////////////////////////////////////////////////////
EVENTS
//////////////////////////////////////////////////////////////*/
event LogSetNewPool(uint256 indexed newPId, address newLPToken, address newRewardContract, address newCurve);
event LogSwitchDex(uint256 indexed id, address newDex);
event LogSetNewDex(uint256 indexed id, address newDex);
event LogChangePool(uint256 indexed newPId, address newLPToken, address newRewardContract, address newCurve);
event LogSetNewSlippageRecover(uint256 slippage);
event LogSetNewSlippage(uint256 slippage);
constructor(address _vault, int128 wantIndex) BaseStrategy(_vault) {
profitFactor = 1000;
uint8 decimals = IERC20Detailed(address(want)).decimals();
debtThreshold = 1_00_000 * (uint256(10)**decimals);
dex = new address[](2);
_switchDex(0, UNISWAP);
_switchDex(1, SUSHISWAP);
require(
(address(want) == DAI && wantIndex == 0) ||
(address(want) == USDC && wantIndex == 1) ||
(address(want) == USDT && wantIndex == 2),
"want and wantIndex does not match"
);
WANT_INDEX = wantIndex;
want.safeApprove(CRV_3POOL, type(uint256).max);
}
/*///////////////////////////////////////////////////////////////
SETTERS
//////////////////////////////////////////////////////////////*/
/** @notice Set a new curve meta pool and convex target for the strategy
* @dev The migration will take place during the next harvest cycle (see prepareReturn)
*/
function setNewPool(uint256 _newPId, address _newCurve) external onlyAuthorized {
require(_newPId != pId, "setMetaPool: same id");
(address lp, , , address reward, , bool shutdown) = Booster(BOOSTER).poolInfo(_newPId);
require(!shutdown, "setMetaPool: pool is shutdown");
IERC20 _newLPToken = IERC20(lp);
newLPToken = _newLPToken;
newRewardContract = reward;
newPId = _newPId;
newCurve = _newCurve;
if (CRV_3POOL_TOKEN.allowance(address(this), newCurve) == 0) {
CRV_3POOL_TOKEN.safeApprove(newCurve, type(uint256).max);
}
if (_newLPToken.allowance(address(this), BOOSTER) == 0) {
_newLPToken.safeApprove(BOOSTER, type(uint256).max);
}
emit LogSetNewPool(_newPId, lp, reward, _newCurve);
}
/** @notice Set how much to lp tokens to withdraw in excess
* @dev curve estimates for calc token amounts are slightly off, correct them by x BP
*/
function setSlippageRecover(uint256 _slippage) external onlyAuthorized {
slippageRecover = _slippage;
emit LogSetNewSlippageRecover(_slippage);
}
/** @notice Amount of slippage we accept
* @dev Since slippage isnt usefull when calculated on chain against an amm, we use
* a straight forward heuristic - assume stable coin price of 1 usd and apply
* slippage against virtual price of lp token
*/
function setSlippage(uint256 _slippage) external onlyAuthorized {
slippage = _slippage;
emit LogSetNewSlippage(_slippage);
}
/** @notice Swap which dex is traded against
*/
function switchDex(uint256 id, address newDex) external onlyAuthorized {
_switchDex(id, newDex);
emit LogSetNewDex(id, newDex);
}
/** @notice Internal switch dex logic
*/
function _switchDex(uint256 id, address newDex) private {
dex[id] = newDex;
IERC20 token;
if (id == 0) {
token = IERC20(CRV);
} else {
token = IERC20(CVX);
}
if (token.allowance(address(this), newDex) == 0) {
token.approve(newDex, type(uint256).max);
}
emit LogSwitchDex(id, newDex);
}
/*///////////////////////////////////////////////////////////////
GETTERS
//////////////////////////////////////////////////////////////*/
function name() external pure override returns (string memory) {
return "StrategyConvexXPool";
}
function estimatedTotalAssets() public view override returns (uint256 estimated) {
estimated = _estimatedTotalAssets(true);
}
/** @notice Get total estimated assets in strategy
* @dev If no curve/convex target is set return balance of strategy
* @param includeReward Include convex rewards in total assets
*/
function _estimatedTotalAssets(bool includeReward) private view returns (uint256 estimated) {
if (rewardContract != address(0)) {
uint256 lpAmount = Rewards(rewardContract).balanceOf(address(this));
if (lpAmount > 0) {
uint256 crv3Amount = ICurveMetaPool(curve).calc_withdraw_one_coin(lpAmount, CRV3_INDEX);
estimated = ICurve3Pool(CRV_3POOL).calc_withdraw_one_coin(crv3Amount, WANT_INDEX);
}
if (includeReward) {
estimated += _claimableBasic(TO_WANT);
}
}
estimated += want.balanceOf(address(this));
}
/*///////////////////////////////////////////////////////////////
EMERGENCY
//////////////////////////////////////////////////////////////*/
/** @notice Forcefully withdraw and sell rewards from convex and curve pools
* @dev Should only be used post emergency state being triggered to ensure all assets are withdrawn
*/
function forceWithdraw() external onlyAuthorized {
_withdrawAll();
}
/*///////////////////////////////////////////////////////////////
CURVE/CONVEX
//////////////////////////////////////////////////////////////*/
/** @notice Interal change pool Logic
*/
function _changePool() private {
uint256 _newPId = newPId;
address _newCurve = newCurve;
IERC20 _newLPToken = newLPToken;
address _newReward = newRewardContract;
pId = _newPId;
curve = _newCurve;
lpToken = _newLPToken;
rewardContract = _newReward;
newCurve = address(0);
newPId = 0;
newLPToken = IERC20(address(0));
newRewardContract = address(0);
emit LogChangePool(_newPId, address(_newLPToken), _newReward, _newCurve);
}
/** @notice Remove all assets into want and sell of rewards
*/
function _withdrawAll() private {
Rewards(rewardContract).withdrawAllAndUnwrap(true);
_sellBasic();
// remove liquidity from metapool
uint256 lpAmount = lpToken.balanceOf(address(this));
ICurveMetaPool _meta = ICurveMetaPool(curve);
uint256 vp = _meta.get_virtual_price();
_meta.remove_liquidity_one_coin(lpAmount, CRV3_INDEX, 0);
// calc min amounts
uint256 minAmount = (lpAmount * vp) / 1E18;
minAmount =
(minAmount - (minAmount * slippage) / 10000) /
(1E18 / 10**IERC20Detailed(address(want)).decimals());
// remove liquidity from 3pool
lpAmount = CRV_3POOL_TOKEN.balanceOf(address(this));
ICurve3Deposit(CRV_3POOL).remove_liquidity_one_coin(lpAmount, WANT_INDEX, minAmount);
}
/** @notice Calculate meta pool token value of want
*/
function wantToLp(uint256 amount) private view returns (uint256 lpAmount) {
uint256[CRV_3POOL_LEN] memory amountsCRV3;
amountsCRV3[uint256(int256(WANT_INDEX))] = amount;
uint256 crv3Amount = ICurve3Pool(CRV_3POOL).calc_token_amount(amountsCRV3, false);
uint256[CRV_METAPOOL_LEN] memory amountsMP;
amountsMP[uint256(int256(CRV3_INDEX))] = crv3Amount;
lpAmount = ICurveMetaPool(curve).calc_token_amount(amountsMP, false);
}
/*///////////////////////////////////////////////////////////////
DEX
//////////////////////////////////////////////////////////////*/
/** @notice Sell reward tokens (crv + cvx)
*/
function _sellBasic() private {
uint256 crv = IERC20(CRV).balanceOf(address(this));
if (crv > 0) {
IUni(dex[0]).swapExactTokensForTokens(
crv,
uint256(0),
_getPath(CRV, TO_WANT),
address(this),
block.timestamp
);
}
uint256 cvx = IERC20(CVX).balanceOf(address(this));
if (cvx > 0) {
IUni(dex[1]).swapExactTokensForTokens(
cvx,
uint256(0),
_getPath(CVX, TO_WANT),
address(this),
block.timestamp
);
}
}
/** @notice Calculate values of rewards tokens (crv + cvx)
*/
function _claimableBasic(uint256 toIndex) private view returns (uint256) {
uint256 crv = Rewards(rewardContract).earned(address(this));
// calculations pulled directly from CVX's contract for minting CVX per CRV claimed
uint256 supply = IERC20(CVX).totalSupply();
uint256 cvx;
uint256 cliff = supply / reductionPerCliff;
// mint if below total cliffs
if (cliff < totalCliffs) {
// for reduction% take inverse of current cliff
uint256 reduction = totalCliffs - cliff;
// reduce
cvx = (crv * reduction) / totalCliffs;
// supply cap check
uint256 amtTillMax = maxSupply - supply;
if (cvx > amtTillMax) {
cvx = amtTillMax;
}
}
uint256 crvValue;
if (crv > 0) {
uint256[] memory crvSwap = IUni(dex[0]).getAmountsOut(crv, _getPath(CRV, toIndex));
crvValue = crvSwap[crvSwap.length - 1];
}
uint256 cvxValue;
if (cvx > 0) {
uint256[] memory cvxSwap = IUni(dex[1]).getAmountsOut(cvx, _getPath(CVX, toIndex));
cvxValue = cvxSwap[cvxSwap.length - 1];
}
return crvValue + cvxValue;
}
/*///////////////////////////////////////////////////////////////
CORE
//////////////////////////////////////////////////////////////*/
/** @notice Add available assets to the curve/convex pool
* @param _debtOutstanding any debt that is owed to the vault,
* should be 0 at this point
*/
function adjustPosition(uint256 _debtOutstanding) internal override {
if (emergencyExit) return;
uint256 wantBal = want.balanceOf(address(this));
if (wantBal > 0) {
uint256[CRV_3POOL_LEN] memory amountsCRV3;
amountsCRV3[uint256(int256(WANT_INDEX))] = wantBal;
ICurve3Deposit(CRV_3POOL).add_liquidity(amountsCRV3, 0);
uint256 crv3Bal = CRV_3POOL_TOKEN.balanceOf(address(this));
if (crv3Bal > 0) {
uint256[CRV_METAPOOL_LEN] memory amountsMP;
amountsMP[uint256(int256(CRV3_INDEX))] = crv3Bal;
ICurveMetaPool _meta = ICurveMetaPool(curve);
uint256 vp = _meta.get_virtual_price();
uint256 minAmount = (wantBal * (1E36 / 10**IERC20Detailed(address(want)).decimals())) / vp;
minAmount = minAmount - (minAmount * slippage) / 10000;
_meta.add_liquidity(amountsMP, minAmount);
uint256 lpBal = lpToken.balanceOf(address(this));
if (lpBal > 0) {
Booster(BOOSTER).deposit(pId, lpBal, true);
}
}
}
}
/** @notice Atempt to remove assets from the curve/convex pool,
* reports a loss is we withdraw less than the required amount
* @param _amountNeeded Amount to remove
*/
function liquidatePosition(uint256 _amountNeeded)
internal
override
returns (uint256 _liquidatedAmount, uint256 _loss)
{
uint256 _wantBal = want.balanceOf(address(this));
if (_wantBal < _amountNeeded) {
_liquidatedAmount = _withdrawSome(_amountNeeded - _wantBal);
_liquidatedAmount = _liquidatedAmount + _wantBal;
_liquidatedAmount = Math.min(_liquidatedAmount, _amountNeeded);
if (_liquidatedAmount < _amountNeeded) {
_loss = _amountNeeded - _liquidatedAmount;
}
} else {
_liquidatedAmount = _amountNeeded;
}
}
/** @notice Withdraw assets from curve/convex pool
* @param _amount Amount to withdraw
*/
function _withdrawSome(uint256 _amount) private returns (uint256) {
uint256 lpAmount = wantToLp(_amount);
lpAmount = lpAmount + (lpAmount * slippageRecover) / 10000;
uint256 poolBal = Rewards(rewardContract).balanceOf(address(this));
if (poolBal < lpAmount) {
lpAmount = poolBal;
}
if (poolBal == 0) return 0;
uint256 before = want.balanceOf(address(this));
// withdraw from convex
Rewards(rewardContract).withdrawAndUnwrap(lpAmount, false);
// remove liquidity from metapool
lpAmount = lpToken.balanceOf(address(this));
ICurveMetaPool _meta = ICurveMetaPool(curve);
uint256 vp = _meta.get_virtual_price();
_meta.remove_liquidity_one_coin(lpAmount, CRV3_INDEX, 0);
// calc min amounts using the metaLp token as the basis
uint256 minAmount = (lpAmount * vp) / 1E18;
minAmount =
(minAmount - (minAmount * slippage) / 10000) /
(1E18 / 10**IERC20Detailed(address(want)).decimals());
// remove liquidity from 3pool
lpAmount = CRV_3POOL_TOKEN.balanceOf(address(this));
ICurve3Deposit(CRV_3POOL).remove_liquidity_one_coin(lpAmount, WANT_INDEX, minAmount);
return want.balanceOf(address(this)) - before;
}
/** @notice Do strategy accounting to determine potential gains/losses and
* pay back any outstanding debt to the vault.
* @dev If a new curve/convex pair has been set, the the strategy will remove
* all assets from the old pair, sell of all rewards and prepare the migration
* to the new pair in this function.
* @param _debtOutstanding Amount of debt owed to the vault
*/
function prepareReturn(uint256 _debtOutstanding)
internal
override
returns (
uint256 _profit,
uint256 _loss,
uint256 _debtPayment
)
{
uint256 total;
uint256 wantBal;
uint256 beforeTotal;
uint256 debt = vault.strategies(address(this)).totalDebt;
if (curve == address(0)) {
// invest into strategy first time
_changePool();
return (0, 0, 0);
} else if (newCurve != address(0)) {
// swap the pool
beforeTotal = _estimatedTotalAssets(true);
_withdrawAll();
_changePool();
wantBal = want.balanceOf(address(this));
total = wantBal;
if (beforeTotal < debt) {
total = Math.max(beforeTotal, total);
} else if (beforeTotal > debt && total < debt) {
total = debt;
}
} else {
Rewards(rewardContract).getReward();
_sellBasic();
total = _estimatedTotalAssets(false);
wantBal = want.balanceOf(address(this));
}
_debtPayment = _debtOutstanding;
if (total > debt) {
_profit = total - debt;
uint256 amountToFree = _profit + _debtPayment;
if (amountToFree > 0 && wantBal < amountToFree) {
_withdrawSome(amountToFree - wantBal);
total = _estimatedTotalAssets(false);
wantBal = want.balanceOf(address(this));
if (total <= debt) {
_profit = 0;
_loss = debt - total;
} else {
_profit = total - debt;
}
amountToFree = _profit + _debtPayment;
if (wantBal < amountToFree) {
if (_profit > wantBal) {
_profit = wantBal;
_debtPayment = 0;
} else {
_debtPayment = Math.min(wantBal - _profit, _debtPayment);
}
}
}
} else {
_loss = debt - total;
uint256 amountToFree = _debtPayment;
if (amountToFree > 0 && wantBal < amountToFree) {
_withdrawSome(amountToFree - wantBal);
wantBal = want.balanceOf(address(this));
if (wantBal < amountToFree) {
_debtPayment = wantBal;
}
}
}
}
function tendTrigger(uint256 callCost) public pure override returns (bool) {
callCost;
return false;
}
/** @notice Check if strategy need to be harvested
* @param callCost Estimated cost of calling harvest in ETH
*/
function harvestTrigger(uint256 callCost) public view override returns (bool) {
StrategyParams memory params = vault.strategies(address(this));
if (params.activation == 0) return false;
if (block.timestamp - params.lastReport < minReportDelay) return false;
if (block.timestamp - params.lastReport >= maxReportDelay) return true;
uint256 outstanding = vault.debtOutstanding();
if (outstanding > debtThreshold) return true;
uint256 total = estimatedTotalAssets();
if (total + debtThreshold < params.totalDebt) return true;
uint256 profit;
if (total > params.totalDebt) {
profit = total - params.totalDebt;
}
return (profitFactor * callCost < _wantToETH(profit));
}
/*///////////////////////////////////////////////////////////////
UTILITY
//////////////////////////////////////////////////////////////*/
/** @notice Get path for uni style pool swap
*/
function _getPath(address from, uint256 toIndex) private view returns (address[] memory path) {
if (toIndex == TO_ETH) {
path = new address[](2);
path[0] = from;
path[1] = WETH;
}
if (toIndex == TO_WANT) {
path = new address[](3);
path[0] = from;
path[1] = WETH;
path[2] = address(want);
}
}
function prepareMigration(address _newStrategy) internal override {
_newStrategy;
_withdrawAll();
}
function protectedTokens() internal pure override returns (address[] memory) {
address[] memory protected = new address[](2);
protected[0] = CRV;
protected[1] = CVX;
return protected;
}
function _wantToETH(uint256 wantAmount) private view returns (uint256) {
if (wantAmount > 0) {
address[] memory path = new address[](2);
path[0] = address(want);
path[1] = WETH;
uint256[] memory amounts = IUni(dex[0]).getAmountsOut(wantAmount, path);
return amounts[1];
}
}
}