// File: contracts/protocol/modules/v1/ClaimModule.sol



/*
    Copyright 2020 Set Labs Inc.
    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.
    SPDX-License-Identifier: Apache License, Version 2.0
*/

pragma solidity 0.6.10;
pragma experimental "ABIEncoderV2";

import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";

import { AddressArrayUtils } from "../../../lib/AddressArrayUtils.sol";
import { IClaimAdapter } from "../../../interfaces/IClaimAdapter.sol";
import { IController } from "../../../interfaces/IController.sol";
import { ISetToken } from "../../../interfaces/ISetToken.sol";
import { ModuleBase } from "../../lib/ModuleBase.sol";


/**
 * @title ClaimModule
 * @author Set Protocol
 *
 * Module that enables managers to claim tokens from external protocols given to the Set as part of participating in
 * incentivized activities of other protocols. The ClaimModule works in conjunction with ClaimAdapters, in which the
 * claimAdapterID / integrationNames are stored on the integration registry.
 *
 * Design:
 * The ecosystem is coalescing around a few standards of how reward programs are created, using forks of popular
 * contracts such as Synthetix's Mintr. Thus, the Claim architecture reflects a more functional vs external-protocol
 * approach where an adapter with common functionality can be used across protocols.
 *
 * Definitions:
 * Reward Pool: A reward pool is a contract associated with an external protocol's reward. Examples of reward pools
 *   include the Curve sUSDV2 Gauge or the Synthetix iBTC StakingReward contract.
 * Adapter: An adapter contains the logic and context for how a reward pool should be claimed - returning the requisite
 *   function signature. Examples of adapters include StakingRewardAdapter (for getting rewards from Synthetix-like
 *   reward contracts) and CurveClaimAdapter (for calling Curve Minter contract's mint function)
 * ClaimSettings: A reward pool can be associated with multiple awards. For example, a Curve liquidity gauge can be
 *   associated with the CURVE_CLAIM adapter to claim CRV and CURVE_DIRECT adapter to claim BPT.
 */
contract ClaimModule is ModuleBase {
    using AddressArrayUtils for address[];

    /* ============ Events ============ */

    event RewardClaimed(
        ISetToken indexed _setToken,
        address indexed _rewardPool,
        IClaimAdapter indexed _adapter,
        uint256 _amount
    );

    event AnyoneClaimUpdated(
        ISetToken indexed _setToken,
        bool _anyoneClaim
    );

    /* ============ Modifiers ============ */

    /**
     * Throws if claim is confined to the manager and caller is not the manager
     */
    modifier onlyValidCaller(ISetToken _setToken) {
        require(_isValidCaller(_setToken), "Must be valid caller");
        _;
    }

    /* ============ State Variables ============ */

    // Indicates if any address can call claim or just the manager of the SetToken
    mapping(ISetToken => bool) public anyoneClaim;

    // Map and array of rewardPool addresses to claim rewards for the SetToken
    mapping(ISetToken => address[]) public rewardPoolList;
    // Map from set tokens to rewards pool address to isAdded boolean. Used to check if a reward pool has been added in O(1) time
    mapping(ISetToken => mapping(address => bool)) public rewardPoolStatus;

    // Map and array of adapters associated to the rewardPool for the SetToken
    mapping(ISetToken => mapping(address => address[])) public claimSettings;
    // Map from set tokens to rewards pool address to claim adapters to isAdded boolean. Used to check if an adapter has been added in O(1) time
    mapping(ISetToken => mapping(address => mapping(address => bool))) public claimSettingsStatus;


    /* ============ Constructor ============ */

    constructor(IController _controller) public ModuleBase(_controller) {}

    /* ============ External Functions ============ */

    /**
     * Claim the rewards available on the rewardPool for the specified claim integration.
     * Callable only by manager unless manager has set anyoneClaim to true.
     *
     * @param _setToken             Address of SetToken
     * @param _rewardPool           Address of the rewardPool that identifies the contract governing claims
     * @param _integrationName      ID of claim module integration (mapping on integration registry)
     */
    function claim(
        ISetToken _setToken,
        address _rewardPool,
        string calldata _integrationName
    )
        external
        onlyValidAndInitializedSet(_setToken)
        onlyValidCaller(_setToken)
    {
        _claim(_setToken, _rewardPool, _integrationName);
    }

    /**
     * Claims rewards on all the passed rewardPool/claim integration pairs. Callable only by manager unless manager has
     * set anyoneClaim to true.
     *
     * @param _setToken             Address of SetToken
     * @param _rewardPools          Addresses of rewardPools that identifies the contract governing claims. Maps to same
     *                                  index integrationNames
     * @param _integrationNames     Human-readable names matching adapter used to collect claim on pool. Maps to same index
     *                                  in rewardPools
     */
    function batchClaim(
        ISetToken _setToken,
        address[] calldata _rewardPools,
        string[] calldata _integrationNames
    )
        external
        onlyValidAndInitializedSet(_setToken)
        onlyValidCaller(_setToken)
    {
        uint256 poolArrayLength = _validateBatchArrays(_rewardPools, _integrationNames);
        for (uint256 i = 0; i < poolArrayLength; i++) {
            _claim(_setToken, _rewardPools[i], _integrationNames[i]);
        }
    }

    /**
     * SET MANAGER ONLY. Update whether manager allows other addresses to call claim.
     *
     * @param _setToken             Address of SetToken
     */
    function updateAnyoneClaim(ISetToken _setToken, bool _anyoneClaim) external onlyManagerAndValidSet(_setToken) {
        anyoneClaim[_setToken] = _anyoneClaim;
        emit AnyoneClaimUpdated(_setToken, _anyoneClaim);
    }
    /**
     * SET MANAGER ONLY. Adds a new claim integration for an existent rewardPool. If rewardPool doesn't have existing
     * claims then rewardPool is added to rewardPoolLiost. The claim integration is associated to an adapter that
     * provides the functionality to claim the rewards for a specific token.
     *
     * @param _setToken             Address of SetToken
     * @param _rewardPool           Address of the rewardPool that identifies the contract governing claims
     * @param _integrationName      ID of claim module integration (mapping on integration registry)
     */
    function addClaim(
        ISetToken _setToken,
        address _rewardPool,
        string calldata _integrationName
    )
        external
        onlyManagerAndValidSet(_setToken)
    {
        _addClaim(_setToken, _rewardPool, _integrationName);
    }

    /**
     * SET MANAGER ONLY. Adds a new rewardPool to the list to perform claims for the SetToken indicating the list of
     * claim integrations. Each claim integration is associated to an adapter that provides the functionality to claim
     * the rewards for a specific token.
     *
     * @param _setToken             Address of SetToken
     * @param _rewardPools          Addresses of rewardPools that identifies the contract governing claims. Maps to same
     *                                  index integrationNames
     * @param _integrationNames     Human-readable names matching adapter used to collect claim on pool. Maps to same index
     *                                  in rewardPools
     */
    function batchAddClaim(
        ISetToken _setToken,
        address[] calldata _rewardPools,
        string[] calldata _integrationNames
    )
        external
        onlyManagerAndValidSet(_setToken)
    {
        _batchAddClaim(_setToken, _rewardPools, _integrationNames);
    }

    /**
     * SET MANAGER ONLY. Removes a claim integration from an existent rewardPool. If no claim remains for reward pool then
     * reward pool is removed from rewardPoolList.
     *
     * @param _setToken             Address of SetToken
     * @param _rewardPool           Address of the rewardPool that identifies the contract governing claims
     * @param _integrationName      ID of claim module integration (mapping on integration registry)
     */
    function removeClaim(
        ISetToken _setToken,
        address _rewardPool,
        string calldata _integrationName
    )
        external
        onlyManagerAndValidSet(_setToken)
    {
        _removeClaim(_setToken, _rewardPool, _integrationName);
    }

    /**
     * SET MANAGER ONLY. Batch removes claims from SetToken's settings.
     *
     * @param _setToken             Address of SetToken
     * @param _rewardPools          Addresses of rewardPools that identifies the contract governing claims. Maps to same index
     *                                  integrationNames
     * @param _integrationNames     Human-readable names matching adapter used to collect claim on pool. Maps to same index in
     *                                  rewardPools
     */
    function batchRemoveClaim(
        ISetToken _setToken,
        address[] calldata _rewardPools,
        string[] calldata _integrationNames
    )
        external
        onlyManagerAndValidSet(_setToken)
    {
        uint256 poolArrayLength = _validateBatchArrays(_rewardPools, _integrationNames);
        for (uint256 i = 0; i < poolArrayLength; i++) {
            _removeClaim(_setToken, _rewardPools[i], _integrationNames[i]);
        }
    }

    /**
     * SET MANAGER ONLY. Initializes this module to the SetToken.
     *
     * @param _setToken             Instance of the SetToken to issue
     * @param _anyoneClaim          Boolean indicating if anyone can claim or just manager
     * @param _rewardPools          Addresses of rewardPools that identifies the contract governing claims. Maps to same index
     *                                  integrationNames
     * @param _integrationNames     Human-readable names matching adapter used to collect claim on pool. Maps to same index in
     *                                  rewardPools
     */
    function initialize(
        ISetToken _setToken,
        bool _anyoneClaim,
        address[] calldata _rewardPools,
        string[] calldata _integrationNames
    )
        external
        onlySetManager(_setToken, msg.sender)
        onlyValidAndPendingSet(_setToken)
    {
        _batchAddClaim(_setToken, _rewardPools, _integrationNames);
        anyoneClaim[_setToken] = _anyoneClaim;
        _setToken.initializeModule();
    }

    /**
     * Removes this module from the SetToken, via call by the SetToken.
     */
    function removeModule() external override {
        delete anyoneClaim[ISetToken(msg.sender)];

        // explicitly delete all elements for gas refund
        address[] memory setTokenPoolList = rewardPoolList[ISetToken(msg.sender)];
        for (uint256 i = 0; i < setTokenPoolList.length; i++) {

            address[] storage adapterList = claimSettings[ISetToken(msg.sender)][setTokenPoolList[i]];
            for (uint256 j = 0; j < adapterList.length; j++) {

                address toRemove = adapterList[j];
                claimSettingsStatus[ISetToken(msg.sender)][setTokenPoolList[i]][toRemove] = false;

                delete adapterList[j];
            }
            delete claimSettings[ISetToken(msg.sender)][setTokenPoolList[i]];
        }

        for (uint256 i = 0; i < rewardPoolList[ISetToken(msg.sender)].length; i++) {
            address toRemove = rewardPoolList[ISetToken(msg.sender)][i];
            rewardPoolStatus[ISetToken(msg.sender)][toRemove] = false;

            delete rewardPoolList[ISetToken(msg.sender)][i];
        }
        delete rewardPoolList[ISetToken(msg.sender)];
    }

    /**
     * Get list of rewardPools to perform claims for the SetToken.
     *
     * @param _setToken             Address of SetToken
     * @return                      Array of rewardPool addresses to claim rewards for the SetToken
     */
    function getRewardPools(ISetToken _setToken) external view returns (address[] memory) {
        return rewardPoolList[_setToken];
    }

    /**
     * Get boolean indicating if the rewardPool is in the list to perform claims for the SetToken.
     *
     * @param _setToken             Address of SetToken
     * @param _rewardPool           Address of rewardPool
     * @return                      Boolean indicating if the rewardPool is in the list for claims.
     */
    function isRewardPool(ISetToken _setToken, address _rewardPool) public view returns (bool) {
        return rewardPoolStatus[_setToken][_rewardPool];
    }

    /**
     * Get list of claim integration of the rewardPool for the SetToken.
     *
     * @param _setToken             Address of SetToken
     * @param _rewardPool           Address of rewardPool
     * @return                      Array of adapter addresses associated to the rewardPool for the SetToken
     */
    function getRewardPoolClaims(ISetToken _setToken, address _rewardPool) external view returns (address[] memory) {
        return claimSettings[_setToken][_rewardPool];
    }

    /**
     * Get boolean indicating if the adapter address of the claim integration is associated to the rewardPool.
     *
     * @param _setToken             Address of SetToken
     * @param _rewardPool           Address of rewardPool
     * @param _integrationName      ID of claim module integration (mapping on integration registry)
     * @return                      Boolean indicating if the claim integration is associated to the rewardPool.
     */
    function isRewardPoolClaim(
        ISetToken _setToken,
        address _rewardPool,
        string calldata _integrationName
    )
        external
        view
        returns (bool)
    {
        address adapter = getAndValidateAdapter(_integrationName);
        return claimSettingsStatus[_setToken][_rewardPool][adapter];
    }

    /**
     * Get the rewards available to be claimed by the claim integration on the rewardPool.
     *
     * @param _setToken             Address of SetToken
     * @param _rewardPool           Address of the rewardPool that identifies the contract governing claims
     * @param _integrationName      ID of claim module integration (mapping on integration registry)
     * @return rewards              Amount of units available to be claimed
     */
    function getRewards(
        ISetToken _setToken,
        address _rewardPool,
        string calldata _integrationName
    )
        external
        view
        returns (uint256)
    {
        IClaimAdapter adapter = _getAndValidateIntegrationAdapter(_setToken, _rewardPool, _integrationName);
        return adapter.getRewardsAmount(_setToken, _rewardPool);
    }

    /* ============ Internal Functions ============ */

    /**
     * Claim the rewards, if available, on the rewardPool using the specified adapter. Interact with the adapter to get
     * the rewards available, the calldata for the SetToken to invoke the claim and the token associated to the claim.
     *
     * @param _setToken             Address of SetToken
     * @param _rewardPool           Address of the rewardPool that identifies the contract governing claims
     * @param _integrationName      Human readable name of claim integration
     */
    function _claim(ISetToken _setToken, address _rewardPool, string calldata _integrationName) internal {
        require(isRewardPool(_setToken, _rewardPool), "RewardPool not present");
        IClaimAdapter adapter = _getAndValidateIntegrationAdapter(_setToken, _rewardPool, _integrationName);

        IERC20 rewardsToken = IERC20(adapter.getTokenAddress(_rewardPool));
        uint256 initRewardsBalance = rewardsToken.balanceOf(address(_setToken));

        (
            address callTarget,
            uint256 callValue,
            bytes memory callByteData
        ) = adapter.getClaimCallData(
            _setToken,
            _rewardPool
        );

        _setToken.invoke(callTarget, callValue, callByteData);

        uint256 finalRewardsBalance = rewardsToken.balanceOf(address(_setToken));

        emit RewardClaimed(_setToken, _rewardPool, adapter, finalRewardsBalance.sub(initRewardsBalance));
    }

    /**
     * Gets the adapter and validate it is associated to the list of claim integration of a rewardPool.
     *
     * @param _setToken             Address of SetToken
     * @param _rewardsPool          Sddress of rewards pool
     * @param _integrationName      ID of claim module integration (mapping on integration registry)
     */
    function _getAndValidateIntegrationAdapter(
        ISetToken _setToken,
        address _rewardsPool,
        string calldata _integrationName
    )
        internal
        view
        returns (IClaimAdapter)
    {
        address adapter = getAndValidateAdapter(_integrationName);
        require(claimSettingsStatus[_setToken][_rewardsPool][adapter], "Adapter integration not present");
        return IClaimAdapter(adapter);
    }

    /**
     * Validates and store the adapter address used to claim rewards for the passed rewardPool. If after adding
     * adapter to pool length of adapters is 1 then add to rewardPoolList as well.
     *
     * @param _setToken                 Address of SetToken
     * @param _rewardPool               Address of the rewardPool that identifies the contract governing claims
     * @param _integrationName          ID of claim module integration (mapping on integration registry)
     */
    function _addClaim(ISetToken _setToken, address _rewardPool, string calldata _integrationName) internal {
        address adapter = getAndValidateAdapter(_integrationName);
        address[] storage _rewardPoolClaimSettings = claimSettings[_setToken][_rewardPool];

        require(!claimSettingsStatus[_setToken][_rewardPool][adapter], "Integration names must be unique");
        _rewardPoolClaimSettings.push(adapter);
        claimSettingsStatus[_setToken][_rewardPool][adapter] = true;

        if (!rewardPoolStatus[_setToken][_rewardPool]) {
            rewardPoolList[_setToken].push(_rewardPool);
            rewardPoolStatus[_setToken][_rewardPool] = true;
        }
    }

    /**
     * Internal version. Adds a new rewardPool to the list to perform claims for the SetToken indicating the list of claim
     * integrations. Each claim integration is associated to an adapter that provides the functionality to claim the rewards
     * for a specific token.
     *
     * @param _setToken             Address of SetToken
     * @param _rewardPools          Addresses of rewardPools that identifies the contract governing claims. Maps to same
     *                                  index integrationNames
     * @param _integrationNames     Human-readable names matching adapter used to collect claim on pool. Maps to same index
     *                                  in rewardPools
     */
    function _batchAddClaim(
        ISetToken _setToken,
        address[] calldata _rewardPools,
        string[] calldata _integrationNames
    )
        internal
    {
        uint256 poolArrayLength = _validateBatchArrays(_rewardPools, _integrationNames);
        for (uint256 i = 0; i < poolArrayLength; i++) {
            _addClaim(_setToken, _rewardPools[i], _integrationNames[i]);
        }
    }

    /**
     * Validates and stores the adapter address used to claim rewards for the passed rewardPool. If no adapters
     * left after removal then remove rewardPool from rewardPoolList and delete entry in claimSettings.
     *
     * @param _setToken                 Address of SetToken
     * @param _rewardPool               Address of the rewardPool that identifies the contract governing claims
     * @param _integrationName          ID of claim module integration (mapping on integration registry)
     */
    function _removeClaim(ISetToken _setToken, address _rewardPool, string calldata _integrationName) internal {
        address adapter = getAndValidateAdapter(_integrationName);

        require(claimSettingsStatus[_setToken][_rewardPool][adapter], "Integration must be added");
        claimSettings[_setToken][_rewardPool].removeStorage(adapter);
        claimSettingsStatus[_setToken][_rewardPool][adapter] = false;

        if (claimSettings[_setToken][_rewardPool].length == 0) {
            rewardPoolList[_setToken].removeStorage(_rewardPool);
            rewardPoolStatus[_setToken][_rewardPool] = false;
        }
    }

    /**
     * For batch functions validate arrays are of equal length and not empty. Return length of array for iteration.
     *
     * @param _rewardPools              Addresses of the rewardPool that identifies the contract governing claims
     * @param _integrationNames         IDs of claim module integration (mapping on integration registry)
     * @return                          Length of arrays
     */
    function _validateBatchArrays(
        address[] memory _rewardPools,
        string[] calldata _integrationNames
    )
        internal
        pure
        returns(uint256)
    {
        uint256 poolArrayLength = _rewardPools.length;
        require(poolArrayLength == _integrationNames.length, "Array length mismatch");
        require(poolArrayLength > 0, "Arrays must not be empty");
        return poolArrayLength;
    }

    /**
     * If claim is confined to the manager, manager must be caller
     *
     * @param _setToken             Address of SetToken
     * @return bool                 Whether or not the caller is valid
     */
    function _isValidCaller(ISetToken _setToken) internal view returns(bool) {
        return anyoneClaim[_setToken] || isSetManager(_setToken, msg.sender);
    }
}
// File: @openzeppelin/contracts/token/ERC20/IERC20.sol



// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <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: contracts/lib/AddressArrayUtils.sol



/*
    Copyright 2020 Set Labs Inc.

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.

    SPDX-License-Identifier: Apache License, Version 2.0

*/

pragma solidity 0.6.10;

/**
 * @title AddressArrayUtils
 * @author Set Protocol
 *
 * Utility functions to handle Address Arrays
 *
 * CHANGELOG:
 * - 4/21/21: Added validatePairsWithArray methods
 */
library AddressArrayUtils {

    /**
     * Finds the index of the first occurrence of the given element.
     * @param A The input array to search
     * @param a The value to find
     * @return Returns (index and isIn) for the first occurrence starting from index 0
     */
    function indexOf(address[] memory A, address a) internal pure returns (uint256, bool) {
        uint256 length = A.length;
        for (uint256 i = 0; i < length; i++) {
            if (A[i] == a) {
                return (i, true);
            }
        }
        return (uint256(-1), false);
    }

    /**
    * Returns true if the value is present in the list. Uses indexOf internally.
    * @param A The input array to search
    * @param a The value to find
    * @return Returns isIn for the first occurrence starting from index 0
    */
    function contains(address[] memory A, address a) internal pure returns (bool) {
        (, bool isIn) = indexOf(A, a);
        return isIn;
    }

    /**
    * Returns true if there are 2 elements that are the same in an array
    * @param A The input array to search
    * @return Returns boolean for the first occurrence of a duplicate
    */
    function hasDuplicate(address[] memory A) internal pure returns(bool) {
        require(A.length > 0, "A is empty");

        for (uint256 i = 0; i < A.length - 1; i++) {
            address current = A[i];
            for (uint256 j = i + 1; j < A.length; j++) {
                if (current == A[j]) {
                    return true;
                }
            }
        }
        return false;
    }

    /**
     * @param A The input array to search
     * @param a The address to remove
     * @return Returns the array with the object removed.
     */
    function remove(address[] memory A, address a)
        internal
        pure
        returns (address[] memory)
    {
        (uint256 index, bool isIn) = indexOf(A, a);
        if (!isIn) {
            revert("Address not in array.");
        } else {
            (address[] memory _A,) = pop(A, index);
            return _A;
        }
    }

    /**
     * @param A The input array to search
     * @param a The address to remove
     */
    function removeStorage(address[] storage A, address a)
        internal
    {
        (uint256 index, bool isIn) = indexOf(A, a);
        if (!isIn) {
            revert("Address not in array.");
        } else {
            uint256 lastIndex = A.length - 1; // If the array would be empty, the previous line would throw, so no underflow here
            if (index != lastIndex) { A[index] = A[lastIndex]; }
            A.pop();
        }
    }

    /**
    * Removes specified index from array
    * @param A The input array to search
    * @param index The index to remove
    * @return Returns the new array and the removed entry
    */
    function pop(address[] memory A, uint256 index)
        internal
        pure
        returns (address[] memory, address)
    {
        uint256 length = A.length;
        require(index < A.length, "Index must be < A length");
        address[] memory newAddresses = new address[](length - 1);
        for (uint256 i = 0; i < index; i++) {
            newAddresses[i] = A[i];
        }
        for (uint256 j = index + 1; j < length; j++) {
            newAddresses[j - 1] = A[j];
        }
        return (newAddresses, A[index]);
    }

    /**
     * Returns the combination of the two arrays
     * @param A The first array
     * @param B The second array
     * @return Returns A extended by B
     */
    function extend(address[] memory A, address[] memory B) internal pure returns (address[] memory) {
        uint256 aLength = A.length;
        uint256 bLength = B.length;
        address[] memory newAddresses = new address[](aLength + bLength);
        for (uint256 i = 0; i < aLength; i++) {
            newAddresses[i] = A[i];
        }
        for (uint256 j = 0; j < bLength; j++) {
            newAddresses[aLength + j] = B[j];
        }
        return newAddresses;
    }

    /**
     * Validate that address and uint array lengths match. Validate address array is not empty
     * and contains no duplicate elements.
     *
     * @param A         Array of addresses
     * @param B         Array of uint
     */
    function validatePairsWithArray(address[] memory A, uint[] memory B) internal pure {
        require(A.length == B.length, "Array length mismatch");
        _validateLengthAndUniqueness(A);
    }

    /**
     * Validate that address and bool array lengths match. Validate address array is not empty
     * and contains no duplicate elements.
     *
     * @param A         Array of addresses
     * @param B         Array of bool
     */
    function validatePairsWithArray(address[] memory A, bool[] memory B) internal pure {
        require(A.length == B.length, "Array length mismatch");
        _validateLengthAndUniqueness(A);
    }

    /**
     * Validate that address and string array lengths match. Validate address array is not empty
     * and contains no duplicate elements.
     *
     * @param A         Array of addresses
     * @param B         Array of strings
     */
    function validatePairsWithArray(address[] memory A, string[] memory B) internal pure {
        require(A.length == B.length, "Array length mismatch");
        _validateLengthAndUniqueness(A);
    }

    /**
     * Validate that address array lengths match, and calling address array are not empty
     * and contain no duplicate elements.
     *
     * @param A         Array of addresses
     * @param B         Array of addresses
     */
    function validatePairsWithArray(address[] memory A, address[] memory B) internal pure {
        require(A.length == B.length, "Array length mismatch");
        _validateLengthAndUniqueness(A);
    }

    /**
     * Validate that address and bytes array lengths match. Validate address array is not empty
     * and contains no duplicate elements.
     *
     * @param A         Array of addresses
     * @param B         Array of bytes
     */
    function validatePairsWithArray(address[] memory A, bytes[] memory B) internal pure {
        require(A.length == B.length, "Array length mismatch");
        _validateLengthAndUniqueness(A);
    }

    /**
     * Validate address array is not empty and contains no duplicate elements.
     *
     * @param A          Array of addresses
     */
    function _validateLengthAndUniqueness(address[] memory A) internal pure {
        require(A.length > 0, "Array length must be > 0");
        require(!hasDuplicate(A), "Cannot duplicate addresses");
    }
}

// File: contracts/interfaces/IClaimAdapter.sol



/*
    Copyright 2020 Set Labs Inc.

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.

    SPDX-License-Identifier: Apache License, Version 2.0
*/

import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";

import { ISetToken } from "../interfaces/ISetToken.sol";

pragma solidity 0.6.10;

/**
 * @title IClaimAdapter
 * @author Set Protocol
 *
 */
interface IClaimAdapter {

    /**
     * Generates the calldata for claiming tokens from the rewars pool
     *
     * @param _setToken     the set token that is owed the tokens
     * @param _rewardPool   the rewards pool to claim from  
     *
     * @return _subject     the rewards pool to call
     * @return _value       the amount of ether to send in the call
     * @return _calldata    the calldata to use
     */
    function getClaimCallData(
        ISetToken _setToken,
        address _rewardPool
    ) external view returns(address _subject, uint256 _value, bytes memory _calldata);

    /**
     * Gets the amount of unclaimed rewards
     *
     * @param _setToken     the set token that is owed the tokens
     * @param _rewardPool   the rewards pool to check
     *
     * @return uint256      the amount of unclaimed rewards
     */
    function getRewardsAmount(ISetToken _setToken, address _rewardPool) external view returns(uint256);

    /**
     * Gets the rewards token
     *
     * @param _rewardPool   the rewards pool to check
     *
     * @return IERC20       the reward token
     */
    function getTokenAddress(address _rewardPool) external view returns(IERC20);
}

// File: contracts/interfaces/IController.sol



/*
    Copyright 2020 Set Labs Inc.

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.

    SPDX-License-Identifier: Apache License, Version 2.0
*/
pragma solidity 0.6.10;

interface IController {
    function addSet(address _setToken) external;
    function feeRecipient() external view returns(address);
    function getModuleFee(address _module, uint256 _feeType) external view returns(uint256);
    function isModule(address _module) external view returns(bool);
    function isSet(address _setToken) external view returns(bool);
    function isSystemContract(address _contractAddress) external view returns (bool);
    function resourceId(uint256 _id) external view returns(address);
}
// File: contracts/interfaces/ISetToken.sol



/*
    Copyright 2020 Set Labs Inc.

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.

    SPDX-License-Identifier: Apache License, Version 2.0
*/
pragma solidity 0.6.10;
pragma experimental "ABIEncoderV2";

import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";

/**
 * @title ISetToken
 * @author Set Protocol
 *
 * Interface for operating with SetTokens.
 */
interface ISetToken is IERC20 {

    /* ============ Enums ============ */

    enum ModuleState {
        NONE,
        PENDING,
        INITIALIZED
    }

    /* ============ Structs ============ */
    /**
     * The base definition of a SetToken Position
     *
     * @param component           Address of token in the Position
     * @param module              If not in default state, the address of associated module
     * @param unit                Each unit is the # of components per 10^18 of a SetToken
     * @param positionState       Position ENUM. Default is 0; External is 1
     * @param data                Arbitrary data
     */
    struct Position {
        address component;
        address module;
        int256 unit;
        uint8 positionState;
        bytes data;
    }

    /**
     * A struct that stores a component's cash position details and external positions
     * This data structure allows O(1) access to a component's cash position units and 
     * virtual units.
     *
     * @param virtualUnit               Virtual value of a component's DEFAULT position. Stored as virtual for efficiency
     *                                  updating all units at once via the position multiplier. Virtual units are achieved
     *                                  by dividing a "real" value by the "positionMultiplier"
     * @param componentIndex            
     * @param externalPositionModules   List of external modules attached to each external position. Each module
     *                                  maps to an external position
     * @param externalPositions         Mapping of module => ExternalPosition struct for a given component
     */
    struct ComponentPosition {
      int256 virtualUnit;
      address[] externalPositionModules;
      mapping(address => ExternalPosition) externalPositions;
    }

    /**
     * A struct that stores a component's external position details including virtual unit and any
     * auxiliary data.
     *
     * @param virtualUnit       Virtual value of a component's EXTERNAL position.
     * @param data              Arbitrary data
     */
    struct ExternalPosition {
      int256 virtualUnit;
      bytes data;
    }


    /* ============ Functions ============ */
    
    function addComponent(address _component) external;
    function removeComponent(address _component) external;
    function editDefaultPositionUnit(address _component, int256 _realUnit) external;
    function addExternalPositionModule(address _component, address _positionModule) external;
    function removeExternalPositionModule(address _component, address _positionModule) external;
    function editExternalPositionUnit(address _component, address _positionModule, int256 _realUnit) external;
    function editExternalPositionData(address _component, address _positionModule, bytes calldata _data) external;

    function invoke(address _target, uint256 _value, bytes calldata _data) external returns(bytes memory);

    function editPositionMultiplier(int256 _newMultiplier) external;

    function mint(address _account, uint256 _quantity) external;
    function burn(address _account, uint256 _quantity) external;

    function lock() external;
    function unlock() external;

    function addModule(address _module) external;
    function removeModule(address _module) external;
    function initializeModule() external;

    function setManager(address _manager) external;

    function manager() external view returns (address);
    function moduleStates(address _module) external view returns (ModuleState);
    function getModules() external view returns (address[] memory);
    
    function getDefaultPositionRealUnit(address _component) external view returns(int256);
    function getExternalPositionRealUnit(address _component, address _positionModule) external view returns(int256);
    function getComponents() external view returns(address[] memory);
    function getExternalPositionModules(address _component) external view returns(address[] memory);
    function getExternalPositionData(address _component, address _positionModule) external view returns(bytes memory);
    function isExternalPositionModule(address _component, address _module) external view returns(bool);
    function isComponent(address _component) external view returns(bool);
    
    function positionMultiplier() external view returns (int256);
    function getPositions() external view returns (Position[] memory);
    function getTotalComponentRealUnits(address _component) external view returns(int256);

    function isInitializedModule(address _module) external view returns(bool);
    function isPendingModule(address _module) external view returns(bool);
    function isLocked() external view returns (bool);
}
// File: contracts/protocol/lib/ModuleBase.sol



/*
    Copyright 2020 Set Labs Inc.

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.

    SPDX-License-Identifier: Apache License, Version 2.0
*/

pragma solidity 0.6.10;

import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";

import { AddressArrayUtils } from "../../lib/AddressArrayUtils.sol";
import { ExplicitERC20 } from "../../lib/ExplicitERC20.sol";
import { IController } from "../../interfaces/IController.sol";
import { IModule } from "../../interfaces/IModule.sol";
import { ISetToken } from "../../interfaces/ISetToken.sol";
import { Invoke } from "./Invoke.sol";
import { Position } from "./Position.sol";
import { PreciseUnitMath } from "../../lib/PreciseUnitMath.sol";
import { ResourceIdentifier } from "./ResourceIdentifier.sol";
import { SafeCast } from "@openzeppelin/contracts/utils/SafeCast.sol";
import { SafeMath } from "@openzeppelin/contracts/math/SafeMath.sol";
import { SignedSafeMath } from "@openzeppelin/contracts/math/SignedSafeMath.sol";

/**
 * @title ModuleBase
 * @author Set Protocol
 *
 * Abstract class that houses common Module-related state and functions.
 *
 * CHANGELOG:
 * - 4/21/21: Delegated modifier logic to internal helpers to reduce contract size
 *
 */
abstract contract ModuleBase is IModule {
    using AddressArrayUtils for address[];
    using Invoke for ISetToken;
    using Position for ISetToken;
    using PreciseUnitMath for uint256;
    using ResourceIdentifier for IController;
    using SafeCast for int256;
    using SafeCast for uint256;
    using SafeMath for uint256;
    using SignedSafeMath for int256;

    /* ============ State Variables ============ */

    // Address of the controller
    IController public controller;

    /* ============ Modifiers ============ */

    modifier onlyManagerAndValidSet(ISetToken _setToken) {
        _validateOnlyManagerAndValidSet(_setToken);
        _;
    }

    modifier onlySetManager(ISetToken _setToken, address _caller) {
        _validateOnlySetManager(_setToken, _caller);
        _;
    }

    modifier onlyValidAndInitializedSet(ISetToken _setToken) {
        _validateOnlyValidAndInitializedSet(_setToken);
        _;
    }

    /**
     * Throws if the sender is not a SetToken's module or module not enabled
     */
    modifier onlyModule(ISetToken _setToken) {
        _validateOnlyModule(_setToken);
        _;
    }

    /**
     * Utilized during module initializations to check that the module is in pending state
     * and that the SetToken is valid
     */
    modifier onlyValidAndPendingSet(ISetToken _setToken) {
        _validateOnlyValidAndPendingSet(_setToken);
        _;
    }

    /* ============ Constructor ============ */

    /**
     * Set state variables and map asset pairs to their oracles
     *
     * @param _controller             Address of controller contract
     */
    constructor(IController _controller) public {
        controller = _controller;
    }

    /* ============ Internal Functions ============ */

    /**
     * Transfers tokens from an address (that has set allowance on the module).
     *
     * @param  _token          The address of the ERC20 token
     * @param  _from           The address to transfer from
     * @param  _to             The address to transfer to
     * @param  _quantity       The number of tokens to transfer
     */
    function transferFrom(IERC20 _token, address _from, address _to, uint256 _quantity) internal {
        ExplicitERC20.transferFrom(_token, _from, _to, _quantity);
    }

    /**
     * Gets the integration for the module with the passed in name. Validates that the address is not empty
     */
    function getAndValidateAdapter(string memory _integrationName) internal view returns(address) { 
        bytes32 integrationHash = getNameHash(_integrationName);
        return getAndValidateAdapterWithHash(integrationHash);
    }

    /**
     * Gets the integration for the module with the passed in hash. Validates that the address is not empty
     */
    function getAndValidateAdapterWithHash(bytes32 _integrationHash) internal view returns(address) { 
        address adapter = controller.getIntegrationRegistry().getIntegrationAdapterWithHash(
            address(this),
            _integrationHash
        );

        require(adapter != address(0), "Must be valid adapter"); 
        return adapter;
    }

    /**
     * Gets the total fee for this module of the passed in index (fee % * quantity)
     */
    function getModuleFee(uint256 _feeIndex, uint256 _quantity) internal view returns(uint256) {
        uint256 feePercentage = controller.getModuleFee(address(this), _feeIndex);
        return _quantity.preciseMul(feePercentage);
    }

    /**
     * Pays the _feeQuantity from the _setToken denominated in _token to the protocol fee recipient
     */
    function payProtocolFeeFromSetToken(ISetToken _setToken, address _token, uint256 _feeQuantity) internal {
        if (_feeQuantity > 0) {
            _setToken.strictInvokeTransfer(_token, controller.feeRecipient(), _feeQuantity); 
        }
    }

    /**
     * Returns true if the module is in process of initialization on the SetToken
     */
    function isSetPendingInitialization(ISetToken _setToken) internal view returns(bool) {
        return _setToken.isPendingModule(address(this));
    }

    /**
     * Returns true if the address is the SetToken's manager
     */
    function isSetManager(ISetToken _setToken, address _toCheck) internal view returns(bool) {
        return _setToken.manager() == _toCheck;
    }

    /**
     * Returns true if SetToken must be enabled on the controller 
     * and module is registered on the SetToken
     */
    function isSetValidAndInitialized(ISetToken _setToken) internal view returns(bool) {
        return controller.isSet(address(_setToken)) &&
            _setToken.isInitializedModule(address(this));
    }

    /**
     * Hashes the string and returns a bytes32 value
     */
    function getNameHash(string memory _name) internal pure returns(bytes32) {
        return keccak256(bytes(_name));
    }

    /* ============== Modifier Helpers ===============
     * Internal functions used to reduce bytecode size
     */

    /**
     * Caller must SetToken manager and SetToken must be valid and initialized
     */
    function _validateOnlyManagerAndValidSet(ISetToken _setToken) internal view {
       require(isSetManager(_setToken, msg.sender), "Must be the SetToken manager");
       require(isSetValidAndInitialized(_setToken), "Must be a valid and initialized SetToken");
    }

    /**
     * Caller must SetToken manager
     */
    function _validateOnlySetManager(ISetToken _setToken, address _caller) internal view {
        require(isSetManager(_setToken, _caller), "Must be the SetToken manager");
    }

    /**
     * SetToken must be valid and initialized
     */
    function _validateOnlyValidAndInitializedSet(ISetToken _setToken) internal view {
        require(isSetValidAndInitialized(_setToken), "Must be a valid and initialized SetToken");
    }

    /**
     * Caller must be initialized module and module must be enabled on the controller
     */
    function _validateOnlyModule(ISetToken _setToken) internal view {
        require(
            _setToken.moduleStates(msg.sender) == ISetToken.ModuleState.INITIALIZED,
            "Only the module can call"
        );

        require(
            controller.isModule(msg.sender),
            "Module must be enabled on controller"
        );
    }

    /**
     * SetToken must be in a pending state and module must be in pending state
     */
    function _validateOnlyValidAndPendingSet(ISetToken _setToken) internal view {
        require(controller.isSet(address(_setToken)), "Must be controller-enabled SetToken");
        require(isSetPendingInitialization(_setToken), "Must be pending initialization");
    }
}
// File: contracts/lib/ExplicitERC20.sol



/*
    Copyright 2020 Set Labs Inc.

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.

    SPDX-License-Identifier: Apache License, Version 2.0
*/

pragma solidity 0.6.10;

import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import { SafeERC20 } from "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
import { SafeMath } from "@openzeppelin/contracts/math/SafeMath.sol";

/**
 * @title ExplicitERC20
 * @author Set Protocol
 *
 * Utility functions for ERC20 transfers that require the explicit amount to be transferred.
 */
library ExplicitERC20 {
    using SafeMath for uint256;

    /**
     * When given allowance, transfers a token from the "_from" to the "_to" of quantity "_quantity".
     * Ensures that the recipient has received the correct quantity (ie no fees taken on transfer)
     *
     * @param _token           ERC20 token to approve
     * @param _from            The account to transfer tokens from
     * @param _to              The account to transfer tokens to
     * @param _quantity        The quantity to transfer
     */
    function transferFrom(
        IERC20 _token,
        address _from,
        address _to,
        uint256 _quantity
    )
        internal
    {
        // Call specified ERC20 contract to transfer tokens (via proxy).
        if (_quantity > 0) {
            uint256 existingBalance = _token.balanceOf(_to);

            SafeERC20.safeTransferFrom(
                _token,
                _from,
                _to,
                _quantity
            );

            uint256 newBalance = _token.balanceOf(_to);

            // Verify transfer quantity is reflected in balance
            require(
                newBalance == existingBalance.add(_quantity),
                "Invalid post transfer balance"
            );
        }
    }
}

// File: contracts/interfaces/IModule.sol



/*
    Copyright 2020 Set Labs Inc.

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.

    SPDX-License-Identifier: Apache License, Version 2.0
*/
pragma solidity 0.6.10;


/**
 * @title IModule
 * @author Set Protocol
 *
 * Interface for interacting with Modules.
 */
interface IModule {
    /**
     * Called by a SetToken to notify that this module was removed from the Set token. Any logic can be included
     * in case checks need to be made or state needs to be cleared.
     */
    function removeModule() external;
}
// File: contracts/protocol/lib/Invoke.sol



/*
    Copyright 2020 Set Labs Inc.

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.

    SPDX-License-Identifier: Apache License, Version 2.0
*/

pragma solidity 0.6.10;

import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import { SafeMath } from "@openzeppelin/contracts/math/SafeMath.sol";

import { ISetToken } from "../../interfaces/ISetToken.sol";


/**
 * @title Invoke
 * @author Set Protocol
 *
 * A collection of common utility functions for interacting with the SetToken's invoke function
 */
library Invoke {
    using SafeMath for uint256;

    /* ============ Internal ============ */

    /**
     * Instructs the SetToken to set approvals of the ERC20 token to a spender.
     *
     * @param _setToken        SetToken instance to invoke
     * @param _token           ERC20 token to approve
     * @param _spender         The account allowed to spend the SetToken's balance
     * @param _quantity        The quantity of allowance to allow
     */
    function invokeApprove(
        ISetToken _setToken,
        address _token,
        address _spender,
        uint256 _quantity
    )
        internal
    {
        bytes memory callData = abi.encodeWithSignature("approve(address,uint256)", _spender, _quantity);
        _setToken.invoke(_token, 0, callData);
    }

    /**
     * Instructs the SetToken to transfer the ERC20 token to a recipient.
     *
     * @param _setToken        SetToken instance to invoke
     * @param _token           ERC20 token to transfer
     * @param _to              The recipient account
     * @param _quantity        The quantity to transfer
     */
    function invokeTransfer(
        ISetToken _setToken,
        address _token,
        address _to,
        uint256 _quantity
    )
        internal
    {
        if (_quantity > 0) {
            bytes memory callData = abi.encodeWithSignature("transfer(address,uint256)", _to, _quantity);
            _setToken.invoke(_token, 0, callData);
        }
    }

    /**
     * Instructs the SetToken to transfer the ERC20 token to a recipient.
     * The new SetToken balance must equal the existing balance less the quantity transferred
     *
     * @param _setToken        SetToken instance to invoke
     * @param _token           ERC20 token to transfer
     * @param _to              The recipient account
     * @param _quantity        The quantity to transfer
     */
    function strictInvokeTransfer(
        ISetToken _setToken,
        address _token,
        address _to,
        uint256 _quantity
    )
        internal
    {
        if (_quantity > 0) {
            // Retrieve current balance of token for the SetToken
            uint256 existingBalance = IERC20(_token).balanceOf(address(_setToken));

            Invoke.invokeTransfer(_setToken, _token, _to, _quantity);

            // Get new balance of transferred token for SetToken
            uint256 newBalance = IERC20(_token).balanceOf(address(_setToken));

            // Verify only the transfer quantity is subtracted
            require(
                newBalance == existingBalance.sub(_quantity),
                "Invalid post transfer balance"
            );
        }
    }

    /**
     * Instructs the SetToken to unwrap the passed quantity of WETH
     *
     * @param _setToken        SetToken instance to invoke
     * @param _weth            WETH address
     * @param _quantity        The quantity to unwrap
     */
    function invokeUnwrapWETH(ISetToken _setToken, address _weth, uint256 _quantity) internal {
        bytes memory callData = abi.encodeWithSignature("withdraw(uint256)", _quantity);
        _setToken.invoke(_weth, 0, callData);
    }

    /**
     * Instructs the SetToken to wrap the passed quantity of ETH
     *
     * @param _setToken        SetToken instance to invoke
     * @param _weth            WETH address
     * @param _quantity        The quantity to unwrap
     */
    function invokeWrapWETH(ISetToken _setToken, address _weth, uint256 _quantity) internal {
        bytes memory callData = abi.encodeWithSignature("deposit()");
        _setToken.invoke(_weth, _quantity, callData);
    }
}
// File: contracts/protocol/lib/Position.sol



/*
    Copyright 2020 Set Labs Inc.

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.

    SPDX-License-Identifier: Apache License, Version 2.0
*/

pragma solidity 0.6.10;
pragma experimental "ABIEncoderV2";

import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import { SafeCast } from "@openzeppelin/contracts/utils/SafeCast.sol";
import { SafeMath } from "@openzeppelin/contracts/math/SafeMath.sol";
import { SignedSafeMath } from "@openzeppelin/contracts/math/SignedSafeMath.sol";

import { ISetToken } from "../../interfaces/ISetToken.sol";
import { PreciseUnitMath } from "../../lib/PreciseUnitMath.sol";


/**
 * @title Position
 * @author Set Protocol
 *
 * Collection of helper functions for handling and updating SetToken Positions
 *
 * CHANGELOG:
 *  - Updated editExternalPosition to work when no external position is associated with module
 */
library Position {
    using SafeCast for uint256;
    using SafeMath for uint256;
    using SafeCast for int256;
    using SignedSafeMath for int256;
    using PreciseUnitMath for uint256;

    /* ============ Helper ============ */

    /**
     * Returns whether the SetToken has a default position for a given component (if the real unit is > 0)
     */
    function hasDefaultPosition(ISetToken _setToken, address _component) internal view returns(bool) {
        return _setToken.getDefaultPositionRealUnit(_component) > 0;
    }

    /**
     * Returns whether the SetToken has an external position for a given component (if # of position modules is > 0)
     */
    function hasExternalPosition(ISetToken _setToken, address _component) internal view returns(bool) {
        return _setToken.getExternalPositionModules(_component).length > 0;
    }
    
    /**
     * Returns whether the SetToken component default position real unit is greater than or equal to units passed in.
     */
    function hasSufficientDefaultUnits(ISetToken _setToken, address _component, uint256 _unit) internal view returns(bool) {
        return _setToken.getDefaultPositionRealUnit(_component) >= _unit.toInt256();
    }

    /**
     * Returns whether the SetToken component external position is greater than or equal to the real units passed in.
     */
    function hasSufficientExternalUnits(
        ISetToken _setToken,
        address _component,
        address _positionModule,
        uint256 _unit
    )
        internal
        view
        returns(bool)
    {
       return _setToken.getExternalPositionRealUnit(_component, _positionModule) >= _unit.toInt256();    
    }

    /**
     * If the position does not exist, create a new Position and add to the SetToken. If it already exists,
     * then set the position units. If the new units is 0, remove the position. Handles adding/removing of 
     * components where needed (in light of potential external positions).
     *
     * @param _setToken           Address of SetToken being modified
     * @param _component          Address of the component
     * @param _newUnit            Quantity of Position units - must be >= 0
     */
    function editDefaultPosition(ISetToken _setToken, address _component, uint256 _newUnit) internal {
        bool isPositionFound = hasDefaultPosition(_setToken, _component);
        if (!isPositionFound && _newUnit > 0) {
            // If there is no Default Position and no External Modules, then component does not exist
            if (!hasExternalPosition(_setToken, _component)) {
                _setToken.addComponent(_component);
            }
        } else if (isPositionFound && _newUnit == 0) {
            // If there is a Default Position and no external positions, remove the component
            if (!hasExternalPosition(_setToken, _component)) {
                _setToken.removeComponent(_component);
            }
        }

        _setToken.editDefaultPositionUnit(_component, _newUnit.toInt256());
    }

    /**
     * Update an external position and remove and external positions or components if necessary. The logic flows as follows:
     * 1) If component is not already added then add component and external position. 
     * 2) If component is added but no existing external position using the passed module exists then add the external position.
     * 3) If the existing position is being added to then just update the unit and data
     * 4) If the position is being closed and no other external positions or default positions are associated with the component
     *    then untrack the component and remove external position.
     * 5) If the position is being closed and other existing positions still exist for the component then just remove the
     *    external position.
     *
     * @param _setToken         SetToken being updated
     * @param _component        Component position being updated
     * @param _module           Module external position is associated with
     * @param _newUnit          Position units of new external position
     * @param _data             Arbitrary data associated with the position
     */
    function editExternalPosition(
        ISetToken _setToken,
        address _component,
        address _module,
        int256 _newUnit,
        bytes memory _data
    )
        internal
    {
        if (_newUnit != 0) {
            if (!_setToken.isComponent(_component)) {
                _setToken.addComponent(_component);
                _setToken.addExternalPositionModule(_component, _module);
            } else if (!_setToken.isExternalPositionModule(_component, _module)) {
                _setToken.addExternalPositionModule(_component, _module);
            }
            _setToken.editExternalPositionUnit(_component, _module, _newUnit);
            _setToken.editExternalPositionData(_component, _module, _data);
        } else {
            require(_data.length == 0, "Passed data must be null");
            // If no default or external position remaining then remove component from components array
            if (_setToken.getExternalPositionRealUnit(_component, _module) != 0) {
                address[] memory positionModules = _setToken.getExternalPositionModules(_component);
                if (_setToken.getDefaultPositionRealUnit(_component) == 0 && positionModules.length == 1) {
                    require(positionModules[0] == _module, "External positions must be 0 to remove component");
                    _setToken.removeComponent(_component);
                }
                _setToken.removeExternalPositionModule(_component, _module);
            }
        }
    }

    /**
     * Get total notional amount of Default position
     *
     * @param _setTokenSupply     Supply of SetToken in precise units (10^18)
     * @param _positionUnit       Quantity of Position units
     *
     * @return                    Total notional amount of units
     */
    function getDefaultTotalNotional(uint256 _setTokenSupply, uint256 _positionUnit) internal pure returns (uint256) {
        return _setTokenSupply.preciseMul(_positionUnit);
    }

    /**
     * Get position unit from total notional amount
     *
     * @param _setTokenSupply     Supply of SetToken in precise units (10^18)
     * @param _totalNotional      Total notional amount of component prior to
     * @return                    Default position unit
     */
    function getDefaultPositionUnit(uint256 _setTokenSupply, uint256 _totalNotional) internal pure returns (uint256) {
        return _totalNotional.preciseDiv(_setTokenSupply);
    }

    /**
     * Get the total tracked balance - total supply * position unit
     *
     * @param _setToken           Address of the SetToken
     * @param _component          Address of the component
     * @return                    Notional tracked balance
     */
    function getDefaultTrackedBalance(ISetToken _setToken, address _component) internal view returns(uint256) {
        int256 positionUnit = _setToken.getDefaultPositionRealUnit(_component); 
        return _setToken.totalSupply().preciseMul(positionUnit.toUint256());
    }

    /**
     * Calculates the new default position unit and performs the edit with the new unit
     *
     * @param _setToken                 Address of the SetToken
     * @param _component                Address of the component
     * @param _setTotalSupply           Current SetToken supply
     * @param _componentPreviousBalance Pre-action component balance
     * @return                          Current component balance
     * @return                          Previous position unit
     * @return                          New position unit
     */
    function calculateAndEditDefaultPosition(
        ISetToken _setToken,
        address _component,
        uint256 _setTotalSupply,
        uint256 _componentPreviousBalance
    )
        internal
        returns(uint256, uint256, uint256)
    {
        uint256 currentBalance = IERC20(_component).balanceOf(address(_setToken));
        uint256 positionUnit = _setToken.getDefaultPositionRealUnit(_component).toUint256();

        uint256 newTokenUnit;
        if (currentBalance > 0) {
            newTokenUnit = calculateDefaultEditPositionUnit(
                _setTotalSupply,
                _componentPreviousBalance,
                currentBalance,
                positionUnit
            );
        } else {
            newTokenUnit = 0;
        }

        editDefaultPosition(_setToken, _component, newTokenUnit);

        return (currentBalance, positionUnit, newTokenUnit);
    }

    /**
     * Calculate the new position unit given total notional values pre and post executing an action that changes SetToken state
     * The intention is to make updates to the units without accidentally picking up airdropped assets as well.
     *
     * @param _setTokenSupply     Supply of SetToken in precise units (10^18)
     * @param _preTotalNotional   Total notional amount of component prior to executing action
     * @param _postTotalNotional  Total notional amount of component after the executing action
     * @param _prePositionUnit    Position unit of SetToken prior to executing action
     * @return                    New position unit
     */
    function calculateDefaultEditPositionUnit(
        uint256 _setTokenSupply,
        uint256 _preTotalNotional,
        uint256 _postTotalNotional,
        uint256 _prePositionUnit
    )
        internal
        pure
        returns (uint256)
    {
        // If pre action total notional amount is greater then subtract post action total notional and calculate new position units
        uint256 airdroppedAmount = _preTotalNotional.sub(_prePositionUnit.preciseMul(_setTokenSupply));
        return _postTotalNotional.sub(airdroppedAmount).preciseDiv(_setTokenSupply);
    }
}

// File: contracts/lib/PreciseUnitMath.sol



/*
    Copyright 2020 Set Labs Inc.

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.

    SPDX-License-Identifier: Apache License, Version 2.0
*/

pragma solidity 0.6.10;
pragma experimental ABIEncoderV2;

import { SafeCast } from "@openzeppelin/contracts/utils/SafeCast.sol";
import { SafeMath } from "@openzeppelin/contracts/math/SafeMath.sol";
import { SignedSafeMath } from "@openzeppelin/contracts/math/SignedSafeMath.sol";


/**
 * @title PreciseUnitMath
 * @author Set Protocol
 *
 * Arithmetic for fixed-point numbers with 18 decimals of precision. Some functions taken from
 * dYdX's BaseMath library.
 *
 * CHANGELOG:
 * - 9/21/20: Added safePower function
 * - 4/21/21: Added approximatelyEquals function
 * - 12/13/21: Added preciseDivCeil (int overloads) function
 * - 12/13/21: Added abs function
 */
library PreciseUnitMath {
    using SafeMath for uint256;
    using SignedSafeMath for int256;
    using SafeCast for int256;

    // The number One in precise units.
    uint256 constant internal PRECISE_UNIT = 10 ** 18;
    int256 constant internal PRECISE_UNIT_INT = 10 ** 18;

    // Max unsigned integer value
    uint256 constant internal MAX_UINT_256 = type(uint256).max;
    // Max and min signed integer value
    int256 constant internal MAX_INT_256 = type(int256).max;
    int256 constant internal MIN_INT_256 = type(int256).min;

    /**
     * @dev Getter function since constants can't be read directly from libraries.
     */
    function preciseUnit() internal pure returns (uint256) {
        return PRECISE_UNIT;
    }

    /**
     * @dev Getter function since constants can't be read directly from libraries.
     */
    function preciseUnitInt() internal pure returns (int256) {
        return PRECISE_UNIT_INT;
    }

    /**
     * @dev Getter function since constants can't be read directly from libraries.
     */
    function maxUint256() internal pure returns (uint256) {
        return MAX_UINT_256;
    }

    /**
     * @dev Getter function since constants can't be read directly from libraries.
     */
    function maxInt256() internal pure returns (int256) {
        return MAX_INT_256;
    }

    /**
     * @dev Getter function since constants can't be read directly from libraries.
     */
    function minInt256() internal pure returns (int256) {
        return MIN_INT_256;
    }

    /**
     * @dev Multiplies value a by value b (result is rounded down). It's assumed that the value b is the significand
     * of a number with 18 decimals precision.
     */
    function preciseMul(uint256 a, uint256 b) internal pure returns (uint256) {
        return a.mul(b).div(PRECISE_UNIT);
    }

    /**
     * @dev Multiplies value a by value b (result is rounded towards zero). It's assumed that the value b is the
     * significand of a number with 18 decimals precision.
     */
    function preciseMul(int256 a, int256 b) internal pure returns (int256) {
        return a.mul(b).div(PRECISE_UNIT_INT);
    }

    /**
     * @dev Multiplies value a by value b (result is rounded up). It's assumed that the value b is the significand
     * of a number with 18 decimals precision.
     */
    function preciseMulCeil(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a == 0 || b == 0) {
            return 0;
        }
        return a.mul(b).sub(1).div(PRECISE_UNIT).add(1);
    }

    /**
     * @dev Divides value a by value b (result is rounded down).
     */
    function preciseDiv(uint256 a, uint256 b) internal pure returns (uint256) {
        return a.mul(PRECISE_UNIT).div(b);
    }


    /**
     * @dev Divides value a by value b (result is rounded towards 0).
     */
    function preciseDiv(int256 a, int256 b) internal pure returns (int256) {
        return a.mul(PRECISE_UNIT_INT).div(b);
    }

    /**
     * @dev Divides value a by value b (result is rounded up or away from 0).
     */
    function preciseDivCeil(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b != 0, "Cant divide by 0");

        return a > 0 ? a.mul(PRECISE_UNIT).sub(1).div(b).add(1) : 0;
    }

    /**
     * @dev Divides value a by value b (result is rounded up or away from 0). When `a` is 0, 0 is
     * returned. When `b` is 0, method reverts with divide-by-zero error.
     */
    function preciseDivCeil(int256 a, int256 b) internal pure returns (int256) {
        require(b != 0, "Cant divide by 0");
        
        a = a.mul(PRECISE_UNIT_INT);
        int256 c = a.div(b);

        if (a % b != 0) {
            // a ^ b == 0 case is covered by the previous if statement, hence it won't resolve to --c
            (a ^ b > 0) ? ++c : --c;
        }

        return c;
    }

    /**
     * @dev Divides value a by value b (result is rounded down - positive numbers toward 0 and negative away from 0).
     */
    function divDown(int256 a, int256 b) internal pure returns (int256) {
        require(b != 0, "Cant divide by 0");
        require(a != MIN_INT_256 || b != -1, "Invalid input");

        int256 result = a.div(b);
        if (a ^ b < 0 && a % b != 0) {
            result -= 1;
        }

        return result;
    }

    /**
     * @dev Multiplies value a by value b where rounding is towards the lesser number.
     * (positive values are rounded towards zero and negative values are rounded away from 0).
     */
    function conservativePreciseMul(int256 a, int256 b) internal pure returns (int256) {
        return divDown(a.mul(b), PRECISE_UNIT_INT);
    }

    /**
     * @dev Divides value a by value b where rounding is towards the lesser number.
     * (positive values are rounded towards zero and negative values are rounded away from 0).
     */
    function conservativePreciseDiv(int256 a, int256 b) internal pure returns (int256) {
        return divDown(a.mul(PRECISE_UNIT_INT), b);
    }

    /**
    * @dev Performs the power on a specified value, reverts on overflow.
    */
    function safePower(
        uint256 a,
        uint256 pow
    )
        internal
        pure
        returns (uint256)
    {
        require(a > 0, "Value must be positive");

        uint256 result = 1;
        for (uint256 i = 0; i < pow; i++){
            uint256 previousResult = result;

            // Using safemath multiplication prevents overflows
            result = previousResult.mul(a);
        }

        return result;
    }

    /**
     * @dev Returns true if a =~ b within range, false otherwise.
     */
    function approximatelyEquals(uint256 a, uint256 b, uint256 range) internal pure returns (bool) {
        return a <= b.add(range) && a >= b.sub(range);
    }

    /**
     * Returns the absolute value of int256 `a` as a uint256
     */
    function abs(int256 a) internal pure returns (uint) {
        return a >= 0 ? a.toUint256() : a.mul(-1).toUint256();
    }

    /**
     * Returns the negation of a
     */
    function neg(int256 a) internal pure returns (int256) {
        require(a > MIN_INT_256, "Inversion overflow");
        return -a;
    }
}

// File: contracts/protocol/lib/ResourceIdentifier.sol



/*
    Copyright 2020 Set Labs Inc.

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.

    SPDX-License-Identifier: Apache License, Version 2.0
*/

pragma solidity 0.6.10;

import { IController } from "../../interfaces/IController.sol";
import { IIntegrationRegistry } from "../../interfaces/IIntegrationRegistry.sol";
import { IPriceOracle } from "../../interfaces/IPriceOracle.sol";
import { ISetValuer } from "../../interfaces/ISetValuer.sol";

/**
 * @title ResourceIdentifier
 * @author Set Protocol
 *
 * A collection of utility functions to fetch information related to Resource contracts in the system
 */
library ResourceIdentifier {

    // IntegrationRegistry will always be resource ID 0 in the system
    uint256 constant internal INTEGRATION_REGISTRY_RESOURCE_ID = 0;
    // PriceOracle will always be resource ID 1 in the system
    uint256 constant internal PRICE_ORACLE_RESOURCE_ID = 1;
    // SetValuer resource will always be resource ID 2 in the system
    uint256 constant internal SET_VALUER_RESOURCE_ID = 2;

    /* ============ Internal ============ */

    /**
     * Gets the instance of integration registry stored on Controller. Note: IntegrationRegistry is stored as index 0 on
     * the Controller
     */
    function getIntegrationRegistry(IController _controller) internal view returns (IIntegrationRegistry) {
        return IIntegrationRegistry(_controller.resourceId(INTEGRATION_REGISTRY_RESOURCE_ID));
    }

    /**
     * Gets instance of price oracle on Controller. Note: PriceOracle is stored as index 1 on the Controller
     */
    function getPriceOracle(IController _controller) internal view returns (IPriceOracle) {
        return IPriceOracle(_controller.resourceId(PRICE_ORACLE_RESOURCE_ID));
    }

    /**
     * Gets the instance of Set valuer on Controller. Note: SetValuer is stored as index 2 on the Controller
     */
    function getSetValuer(IController _controller) internal view returns (ISetValuer) {
        return ISetValuer(_controller.resourceId(SET_VALUER_RESOURCE_ID));
    }
}
// File: @openzeppelin/contracts/utils/SafeCast.sol



// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;


/**
 * @dev Wrappers over Solidity's uintXX/intXX casting operators with added overflow
 * checks.
 *
 * Downcasting from uint256/int256 in Solidity does not revert on overflow. This can
 * easily result in undesired exploitation or bugs, since developers usually
 * assume that overflows raise errors. `SafeCast` restores this intuition by
 * reverting the transaction when such an operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 *
 * Can be combined with {SafeMath} and {SignedSafeMath} to extend it to smaller types, by performing
 * all math on `uint256` and `int256` and then downcasting.
 */
library SafeCast {

    /**
     * @dev Returns the downcasted uint128 from uint256, reverting on
     * overflow (when the input is greater than largest uint128).
     *
     * Counterpart to Solidity's `uint128` operator.
     *
     * Requirements:
     *
     * - input must fit into 128 bits
     */
    function toUint128(uint256 value) internal pure returns (uint128) {
        require(value < 2**128, "SafeCast: value doesn\'t fit in 128 bits");
        return uint128(value);
    }

    /**
     * @dev Returns the downcasted uint64 from uint256, reverting on
     * overflow (when the input is greater than largest uint64).
     *
     * Counterpart to Solidity's `uint64` operator.
     *
     * Requirements:
     *
     * - input must fit into 64 bits
     */
    function toUint64(uint256 value) internal pure returns (uint64) {
        require(value < 2**64, "SafeCast: value doesn\'t fit in 64 bits");
        return uint64(value);
    }

    /**
     * @dev Returns the downcasted uint32 from uint256, reverting on
     * overflow (when the input is greater than largest uint32).
     *
     * Counterpart to Solidity's `uint32` operator.
     *
     * Requirements:
     *
     * - input must fit into 32 bits
     */
    function toUint32(uint256 value) internal pure returns (uint32) {
        require(value < 2**32, "SafeCast: value doesn\'t fit in 32 bits");
        return uint32(value);
    }

    /**
     * @dev Returns the downcasted uint16 from uint256, reverting on
     * overflow (when the input is greater than largest uint16).
     *
     * Counterpart to Solidity's `uint16` operator.
     *
     * Requirements:
     *
     * - input must fit into 16 bits
     */
    function toUint16(uint256 value) internal pure returns (uint16) {
        require(value < 2**16, "SafeCast: value doesn\'t fit in 16 bits");
        return uint16(value);
    }

    /**
     * @dev Returns the downcasted uint8 from uint256, reverting on
     * overflow (when the input is greater than largest uint8).
     *
     * Counterpart to Solidity's `uint8` operator.
     *
     * Requirements:
     *
     * - input must fit into 8 bits.
     */
    function toUint8(uint256 value) internal pure returns (uint8) {
        require(value < 2**8, "SafeCast: value doesn\'t fit in 8 bits");
        return uint8(value);
    }

    /**
     * @dev Converts a signed int256 into an unsigned uint256.
     *
     * Requirements:
     *
     * - input must be greater than or equal to 0.
     */
    function toUint256(int256 value) internal pure returns (uint256) {
        require(value >= 0, "SafeCast: value must be positive");
        return uint256(value);
    }

    /**
     * @dev Returns the downcasted int128 from int256, reverting on
     * overflow (when the input is less than smallest int128 or
     * greater than largest int128).
     *
     * Counterpart to Solidity's `int128` operator.
     *
     * Requirements:
     *
     * - input must fit into 128 bits
     *
     * _Available since v3.1._
     */
    function toInt128(int256 value) internal pure returns (int128) {
        require(value >= -2**127 && value < 2**127, "SafeCast: value doesn\'t fit in 128 bits");
        return int128(value);
    }

    /**
     * @dev Returns the downcasted int64 from int256, reverting on
     * overflow (when the input is less than smallest int64 or
     * greater than largest int64).
     *
     * Counterpart to Solidity's `int64` operator.
     *
     * Requirements:
     *
     * - input must fit into 64 bits
     *
     * _Available since v3.1._
     */
    function toInt64(int256 value) internal pure returns (int64) {
        require(value >= -2**63 && value < 2**63, "SafeCast: value doesn\'t fit in 64 bits");
        return int64(value);
    }

    /**
     * @dev Returns the downcasted int32 from int256, reverting on
     * overflow (when the input is less than smallest int32 or
     * greater than largest int32).
     *
     * Counterpart to Solidity's `int32` operator.
     *
     * Requirements:
     *
     * - input must fit into 32 bits
     *
     * _Available since v3.1._
     */
    function toInt32(int256 value) internal pure returns (int32) {
        require(value >= -2**31 && value < 2**31, "SafeCast: value doesn\'t fit in 32 bits");
        return int32(value);
    }

    /**
     * @dev Returns the downcasted int16 from int256, reverting on
     * overflow (when the input is less than smallest int16 or
     * greater than largest int16).
     *
     * Counterpart to Solidity's `int16` operator.
     *
     * Requirements:
     *
     * - input must fit into 16 bits
     *
     * _Available since v3.1._
     */
    function toInt16(int256 value) internal pure returns (int16) {
        require(value >= -2**15 && value < 2**15, "SafeCast: value doesn\'t fit in 16 bits");
        return int16(value);
    }

    /**
     * @dev Returns the downcasted int8 from int256, reverting on
     * overflow (when the input is less than smallest int8 or
     * greater than largest int8).
     *
     * Counterpart to Solidity's `int8` operator.
     *
     * Requirements:
     *
     * - input must fit into 8 bits.
     *
     * _Available since v3.1._
     */
    function toInt8(int256 value) internal pure returns (int8) {
        require(value >= -2**7 && value < 2**7, "SafeCast: value doesn\'t fit in 8 bits");
        return int8(value);
    }

    /**
     * @dev Converts an unsigned uint256 into a signed int256.
     *
     * Requirements:
     *
     * - input must be less than or equal to maxInt256.
     */
    function toInt256(uint256 value) internal pure returns (int256) {
        require(value < 2**255, "SafeCast: value doesn't fit in an int256");
        return int256(value);
    }
}

// File: @openzeppelin/contracts/math/SafeMath.sol



// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when an
 * operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 */
library SafeMath {
    /**
     * @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) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");

        return c;
    }

    /**
     * @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 sub(a, b, "SafeMath: subtraction overflow");
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        uint256 c = a - b;

        return c;
    }

    /**
     * @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) {
        // 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 0;
        }

        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");

        return c;
    }

    /**
     * @dev Returns the integer division of two unsigned integers. Reverts 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) internal pure returns (uint256) {
        return div(a, b, "SafeMath: division by zero");
    }

    /**
     * @dev Returns the integer division of two unsigned integers. Reverts 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) {
        require(b > 0, errorMessage);
        uint256 c = a / b;
        // assert(a == b * c + a % b); // There is no case in which this doesn't hold

        return c;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * Reverts 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 mod(a, b, "SafeMath: modulo by zero");
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * Reverts with custom message 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, string memory errorMessage) internal pure returns (uint256) {
        require(b != 0, errorMessage);
        return a % b;
    }
}

// File: @openzeppelin/contracts/math/SignedSafeMath.sol



// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

/**
 * @title SignedSafeMath
 * @dev Signed math operations with safety checks that revert on error.
 */
library SignedSafeMath {
    int256 constant private _INT256_MIN = -2**255;

    /**
     * @dev Returns the multiplication of two signed integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(int256 a, int256 b) internal pure returns (int256) {
        // 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 0;
        }

        require(!(a == -1 && b == _INT256_MIN), "SignedSafeMath: multiplication overflow");

        int256 c = a * b;
        require(c / a == b, "SignedSafeMath: multiplication overflow");

        return c;
    }

    /**
     * @dev Returns the integer division of two signed integers. Reverts 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(int256 a, int256 b) internal pure returns (int256) {
        require(b != 0, "SignedSafeMath: division by zero");
        require(!(b == -1 && a == _INT256_MIN), "SignedSafeMath: division overflow");

        int256 c = a / b;

        return c;
    }

    /**
     * @dev Returns the subtraction of two signed integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(int256 a, int256 b) internal pure returns (int256) {
        int256 c = a - b;
        require((b >= 0 && c <= a) || (b < 0 && c > a), "SignedSafeMath: subtraction overflow");

        return c;
    }

    /**
     * @dev Returns the addition of two signed integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(int256 a, int256 b) internal pure returns (int256) {
        int256 c = a + b;
        require((b >= 0 && c >= a) || (b < 0 && c < a), "SignedSafeMath: addition overflow");

        return c;
    }
}

// File: @openzeppelin/contracts/token/ERC20/SafeERC20.sol



// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

import "./IERC20.sol";
import "../../math/SafeMath.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 SafeMath for uint256;
    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).add(value);
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }

    function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).sub(value, "SafeERC20: decreased allowance below zero");
        _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: @openzeppelin/contracts/utils/Address.sol



// SPDX-License-Identifier: MIT

pragma solidity >=0.6.2 <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);
    }

    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: contracts/interfaces/IIntegrationRegistry.sol



/*
    Copyright 2020 Set Labs Inc.

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.

    SPDX-License-Identifier: Apache License, Version 2.0
*/
pragma solidity 0.6.10;

interface IIntegrationRegistry {
    function addIntegration(address _module, string memory _id, address _wrapper) external;
    function getIntegrationAdapter(address _module, string memory _id) external view returns(address);
    function getIntegrationAdapterWithHash(address _module, bytes32 _id) external view returns(address);
    function isValidIntegration(address _module, string memory _id) external view returns(bool);
}
// File: contracts/interfaces/IPriceOracle.sol



/*
    Copyright 2020 Set Labs Inc.

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.

    SPDX-License-Identifier: Apache License, Version 2.0
*/
pragma solidity 0.6.10;

/**
 * @title IPriceOracle
 * @author Set Protocol
 *
 * Interface for interacting with PriceOracle
 */
interface IPriceOracle {

    /* ============ Functions ============ */

    function getPrice(address _assetOne, address _assetTwo) external view returns (uint256);
    function masterQuoteAsset() external view returns (address);
}
// File: contracts/interfaces/ISetValuer.sol



/*
    Copyright 2020 Set Labs Inc.

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.

    SPDX-License-Identifier: Apache License, Version 2.0
*/
pragma solidity 0.6.10;

import { ISetToken } from "../interfaces/ISetToken.sol";

interface ISetValuer {
    function calculateSetTokenValuation(ISetToken _setToken, address _quoteAsset) external view returns (uint256);
}