// SPDX-License-Identifier: MIT

pragma solidity ^0.6.0;

/**
 * @dev Library for managing
 * https://en.wikipedia.org/wiki/Set_(abstract_data_type)[sets] of primitive
 * types.
 *
 * Sets have the following properties:
 *
 * - Elements are added, removed, and checked for existence in constant time
 * (O(1)).
 * - Elements are enumerated in O(n). No guarantees are made on the ordering.
 *
 * ```
 * contract Example {
 *     // Add the library methods
 *     using EnumerableSet for EnumerableSet.AddressSet;
 *
 *     // Declare a set state variable
 *     EnumerableSet.AddressSet private mySet;
 * }
 * ```
 *
 * As of v3.0.0, only sets of type `address` (`AddressSet`) and `uint256`
 * (`UintSet`) are supported.
 */
library EnumerableSet {
    // To implement this library for multiple types with as little code
    // repetition as possible, we write it in terms of a generic Set type with
    // bytes32 values.
    // The Set implementation uses private functions, and user-facing
    // implementations (such as AddressSet) are just wrappers around the
    // underlying Set.
    // This means that we can only create new EnumerableSets for types that fit
    // in bytes32.

    struct Set {
        // Storage of set values
        bytes32[] _values;

        // Position of the value in the `values` array, plus 1 because index 0
        // means a value is not in the set.
        mapping (bytes32 => uint256) _indexes;
    }

    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function _add(Set storage set, bytes32 value) private returns (bool) {
        if (!_contains(set, value)) {
            set._values.push(value);
            // The value is stored at length-1, but we add 1 to all indexes
            // and use 0 as a sentinel value
            set._indexes[value] = set._values.length;
            return true;
        } else {
            return false;
        }
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function _remove(Set storage set, bytes32 value) private returns (bool) {
        // We read and store the value's index to prevent multiple reads from the same storage slot
        uint256 valueIndex = set._indexes[value];

        if (valueIndex != 0) { // Equivalent to contains(set, value)
            // To delete an element from the _values array in O(1), we swap the element to delete with the last one in
            // the array, and then remove the last element (sometimes called as 'swap and pop').
            // This modifies the order of the array, as noted in {at}.

            uint256 toDeleteIndex = valueIndex - 1;
            uint256 lastIndex = set._values.length - 1;

            // When the value to delete is the last one, the swap operation is unnecessary. However, since this occurs
            // so rarely, we still do the swap anyway to avoid the gas cost of adding an 'if' statement.

            bytes32 lastvalue = set._values[lastIndex];

            // Move the last value to the index where the value to delete is
            set._values[toDeleteIndex] = lastvalue;
            // Update the index for the moved value
            set._indexes[lastvalue] = toDeleteIndex + 1; // All indexes are 1-based

            // Delete the slot where the moved value was stored
            set._values.pop();

            // Delete the index for the deleted slot
            delete set._indexes[value];

            return true;
        } else {
            return false;
        }
    }

    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function _contains(Set storage set, bytes32 value) private view returns (bool) {
        return set._indexes[value] != 0;
    }

    /**
     * @dev Returns the number of values on the set. O(1).
     */
    function _length(Set storage set) private view returns (uint256) {
        return set._values.length;
    }

   /**
    * @dev Returns the value stored at position `index` in the set. O(1).
    *
    * Note that there are no guarantees on the ordering of values inside the
    * array, and it may change when more values are added or removed.
    *
    * Requirements:
    *
    * - `index` must be strictly less than {length}.
    */
    function _at(Set storage set, uint256 index) private view returns (bytes32) {
        require(set._values.length > index, "EnumerableSet: index out of bounds");
        return set._values[index];
    }

    // AddressSet

    struct AddressSet {
        Set _inner;
    }

    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(AddressSet storage set, address value) internal returns (bool) {
        return _add(set._inner, bytes32(uint256(value)));
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(AddressSet storage set, address value) internal returns (bool) {
        return _remove(set._inner, bytes32(uint256(value)));
    }

    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(AddressSet storage set, address value) internal view returns (bool) {
        return _contains(set._inner, bytes32(uint256(value)));
    }

    /**
     * @dev Returns the number of values in the set. O(1).
     */
    function length(AddressSet storage set) internal view returns (uint256) {
        return _length(set._inner);
    }

   /**
    * @dev Returns the value stored at position `index` in the set. O(1).
    *
    * Note that there are no guarantees on the ordering of values inside the
    * array, and it may change when more values are added or removed.
    *
    * Requirements:
    *
    * - `index` must be strictly less than {length}.
    */
    function at(AddressSet storage set, uint256 index) internal view returns (address) {
        return address(uint256(_at(set._inner, index)));
    }


    // UintSet

    struct UintSet {
        Set _inner;
    }

    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(UintSet storage set, uint256 value) internal returns (bool) {
        return _add(set._inner, bytes32(value));
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(UintSet storage set, uint256 value) internal returns (bool) {
        return _remove(set._inner, bytes32(value));
    }

    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(UintSet storage set, uint256 value) internal view returns (bool) {
        return _contains(set._inner, bytes32(value));
    }

    /**
     * @dev Returns the number of values on the set. O(1).
     */
    function length(UintSet storage set) internal view returns (uint256) {
        return _length(set._inner);
    }

   /**
    * @dev Returns the value stored at position `index` in the set. O(1).
    *
    * Note that there are no guarantees on the ordering of values inside the
    * array, and it may change when more values are added or removed.
    *
    * Requirements:
    *
    * - `index` must be strictly less than {length}.
    */
    function at(UintSet storage set, uint256 index) internal view returns (uint256) {
        return uint256(_at(set._inner, index));
    }
}

// SPDX-License-Identifier: GPL-3.0

/*
    This file is part of the Enzyme Protocol.

    (c) Enzyme Council <council@enzyme.finance>

    For the full license information, please view the LICENSE
    file that was distributed with this source code.
*/

pragma solidity 0.6.12;

import "../../core/fund/comptroller/IComptroller.sol";
import "../../core/fund/vault/IVault.sol";
import "../IExtension.sol";

/// @title ExtensionBase Contract
/// @author Enzyme Council <security@enzyme.finance>
/// @notice Base class for an extension
abstract contract ExtensionBase is IExtension {
    mapping(address => address) internal comptrollerProxyToVaultProxy;

    /// @notice Allows extension to run logic during fund activation
    /// @dev Unimplemented by default, may be overridden.
    function activateForFund(bool) external virtual override {
        return;
    }

    /// @notice Allows extension to run logic during fund deactivation (destruct)
    /// @dev Unimplemented by default, may be overridden.
    function deactivateForFund() external virtual override {
        return;
    }

    /// @notice Receives calls from ComptrollerLib.callOnExtension()
    /// and dispatches the appropriate action
    /// @dev Unimplemented by default, may be overridden.
    function receiveCallFromComptroller(
        address,
        uint256,
        bytes calldata
    ) external virtual override {
        revert("receiveCallFromComptroller: Unimplemented for Extension");
    }

    /// @notice Allows extension to run logic during fund configuration
    /// @dev Unimplemented by default, may be overridden.
    function setConfigForFund(bytes calldata) external virtual override {
        return;
    }

    /// @dev Helper to validate a ComptrollerProxy-VaultProxy relation, which we store for both
    /// gas savings and to guarantee a spoofed ComptrollerProxy does not change getVaultProxy().
    /// Will revert without reason if the expected interfaces do not exist.
    function __setValidatedVaultProxy(address _comptrollerProxy)
        internal
        returns (address vaultProxy_)
    {
        require(
            comptrollerProxyToVaultProxy[_comptrollerProxy] == address(0),
            "__setValidatedVaultProxy: Already set"
        );

        vaultProxy_ = IComptroller(_comptrollerProxy).getVaultProxy();
        require(vaultProxy_ != address(0), "__setValidatedVaultProxy: Missing vaultProxy");

        require(
            _comptrollerProxy == IVault(vaultProxy_).getAccessor(),
            "__setValidatedVaultProxy: Not the VaultProxy accessor"
        );

        comptrollerProxyToVaultProxy[_comptrollerProxy] = vaultProxy_;

        return vaultProxy_;
    }

    ///////////////////
    // STATE GETTERS //
    ///////////////////

    /// @notice Gets the verified VaultProxy for a given ComptrollerProxy
    /// @param _comptrollerProxy The ComptrollerProxy of the fund
    /// @return vaultProxy_ The VaultProxy of the fund
    function getVaultProxyForFund(address _comptrollerProxy)
        public
        view
        returns (address vaultProxy_)
    {
        return comptrollerProxyToVaultProxy[_comptrollerProxy];
    }
}

// SPDX-License-Identifier: GPL-3.0

/*
    This file is part of the Enzyme Protocol.

    (c) Enzyme Council <council@enzyme.finance>

    For the full license information, please view the LICENSE
    file that was distributed with this source code.
*/

pragma solidity 0.6.12;

import "../../core/fund-deployer/IFundDeployer.sol";

/// @title FundDeployerOwnerMixin Contract
/// @author Enzyme Council <security@enzyme.finance>
/// @notice A mixin contract that defers ownership to the owner of FundDeployer
abstract contract FundDeployerOwnerMixin {
    address internal immutable FUND_DEPLOYER;

    modifier onlyFundDeployerOwner() {
        require(
            msg.sender == getOwner(),
            "onlyFundDeployerOwner: Only the FundDeployer owner can call this function"
        );
        _;
    }

    constructor(address _fundDeployer) public {
        FUND_DEPLOYER = _fundDeployer;
    }

    /// @notice Gets the owner of this contract
    /// @return owner_ The owner
    /// @dev Ownership is deferred to the owner of the FundDeployer contract
    function getOwner() public view returns (address owner_) {
        return IFundDeployer(FUND_DEPLOYER).getOwner();
    }

    ///////////////////
    // STATE GETTERS //
    ///////////////////

    /// @notice Gets the `FUND_DEPLOYER` variable
    /// @return fundDeployer_ The `FUND_DEPLOYER` variable value
    function getFundDeployer() external view returns (address fundDeployer_) {
        return FUND_DEPLOYER;
    }
}

// SPDX-License-Identifier: GPL-3.0

/*
    This file is part of the Enzyme Protocol.

    (c) Enzyme Council <council@enzyme.finance>

    For the full license information, please view the LICENSE
    file that was distributed with this source code.
*/

pragma solidity 0.6.12;

/// @title IComptroller Interface
/// @author Enzyme Council <security@enzyme.finance>
interface IComptroller {
    enum VaultAction {
        None,
        BurnShares,
        MintShares,
        TransferShares,
        ApproveAssetSpender,
        WithdrawAssetTo,
        AddTrackedAsset,
        RemoveTrackedAsset
    }

    function activate(address, bool) external;

    function calcGav(bool) external returns (uint256, bool);

    function calcGrossShareValue(bool) external returns (uint256, bool);

    function callOnExtension(
        address,
        uint256,
        bytes calldata
    ) external;

    function configureExtensions(bytes calldata, bytes calldata) external;

    function destruct() external;

    function getDenominationAsset() external view returns (address);

    function getVaultProxy() external view returns (address);

    function init(address, uint256) external;

    function permissionedVaultAction(VaultAction, bytes calldata) external;
}

// SPDX-License-Identifier: GPL-3.0

/*
    This file is part of the Enzyme Protocol.

    (c) Enzyme Council <council@enzyme.finance>

    For the full license information, please view the LICENSE
    file that was distributed with this source code.
*/

pragma solidity 0.6.12;

/// @title IExtension Interface
/// @author Enzyme Council <security@enzyme.finance>
/// @notice Interface for all extensions
interface IExtension {
    function activateForFund(bool _isMigration) external;

    function deactivateForFund() external;

    function receiveCallFromComptroller(
        address _comptrollerProxy,
        uint256 _actionId,
        bytes calldata _callArgs
    ) external;

    function setConfigForFund(bytes calldata _configData) external;
}

// SPDX-License-Identifier: GPL-3.0

/*
    This file is part of the Enzyme Protocol.

    (c) Enzyme Council <council@enzyme.finance>

    For the full license information, please view the LICENSE
    file that was distributed with this source code.
*/

pragma solidity 0.6.12;

/// @title IFundDeployer Interface
/// @author Enzyme Council <security@enzyme.finance>
interface IFundDeployer {
    enum ReleaseStatus {PreLaunch, Live, Paused}

    function getOwner() external view returns (address);

    function getReleaseStatus() external view returns (ReleaseStatus);

    function isRegisteredVaultCall(address, bytes4) external view returns (bool);
}

// SPDX-License-Identifier: GPL-3.0

/*
    This file is part of the Enzyme Protocol.

    (c) Enzyme Council <council@enzyme.finance>

    For the full license information, please view the LICENSE
    file that was distributed with this source code.
*/

pragma solidity 0.6.12;

/// @title IMigratableVault Interface
/// @author Enzyme Council <security@enzyme.finance>
/// @dev DO NOT EDIT CONTRACT
interface IMigratableVault {
    function canMigrate(address _who) external view returns (bool canMigrate_);

    function init(
        address _owner,
        address _accessor,
        string calldata _fundName
    ) external;

    function setAccessor(address _nextAccessor) external;

    function setVaultLib(address _nextVaultLib) external;
}

// SPDX-License-Identifier: GPL-3.0

/*
    This file is part of the Enzyme Protocol.

    (c) Enzyme Council <council@enzyme.finance>

    For the full license information, please view the LICENSE
    file that was distributed with this source code.
*/

pragma solidity 0.6.12;

import "./IPolicyManager.sol";

/// @title Policy Interface
/// @author Enzyme Council <security@enzyme.finance>
interface IPolicy {
    function activateForFund(address _comptrollerProxy, address _vaultProxy) external;

    function addFundSettings(address _comptrollerProxy, bytes calldata _encodedSettings) external;

    function identifier() external pure returns (string memory identifier_);

    function implementedHooks()
        external
        view
        returns (IPolicyManager.PolicyHook[] memory implementedHooks_);

    function updateFundSettings(
        address _comptrollerProxy,
        address _vaultProxy,
        bytes calldata _encodedSettings
    ) external;

    function validateRule(
        address _comptrollerProxy,
        address _vaultProxy,
        IPolicyManager.PolicyHook _hook,
        bytes calldata _encodedArgs
    ) external returns (bool isValid_);
}

// SPDX-License-Identifier: GPL-3.0

/*
    This file is part of the Enzyme Protocol.

    (c) Enzyme Council <council@enzyme.finance>

    For the full license information, please view the LICENSE
    file that was distributed with this source code.
*/

pragma solidity 0.6.12;
pragma experimental ABIEncoderV2;

/// @title PolicyManager Interface
/// @author Enzyme Council <security@enzyme.finance>
/// @notice Interface for the PolicyManager
interface IPolicyManager {
    enum PolicyHook {
        BuySharesSetup,
        PreBuyShares,
        PostBuyShares,
        BuySharesCompleted,
        PreCallOnIntegration,
        PostCallOnIntegration
    }

    function validatePolicies(
        address,
        PolicyHook,
        bytes calldata
    ) external;
}

// SPDX-License-Identifier: GPL-3.0

/*
    This file is part of the Enzyme Protocol.

    (c) Enzyme Council <council@enzyme.finance>

    For the full license information, please view the LICENSE
    file that was distributed with this source code.
*/

pragma solidity 0.6.12;

import "../../../../persistent/utils/IMigratableVault.sol";

/// @title IVault Interface
/// @author Enzyme Council <security@enzyme.finance>
interface IVault is IMigratableVault {
    function addTrackedAsset(address) external;

    function approveAssetSpender(
        address,
        address,
        uint256
    ) external;

    function burnShares(address, uint256) external;

    function callOnContract(address, bytes calldata) external;

    function getAccessor() external view returns (address);

    function getOwner() external view returns (address);

    function getTrackedAssets() external view returns (address[] memory);

    function isTrackedAsset(address) external view returns (bool);

    function mintShares(address, uint256) external;

    function removeTrackedAsset(address) external;

    function transferShares(
        address,
        address,
        uint256
    ) external;

    function withdrawAssetTo(
        address,
        address,
        uint256
    ) external;
}

// SPDX-License-Identifier: GPL-3.0

/*
    This file is part of the Enzyme Protocol.

    (c) Enzyme Council <council@enzyme.finance>

    For the full license information, please view the LICENSE
    file that was distributed with this source code.
*/

pragma solidity 0.6.12;
pragma experimental ABIEncoderV2;

import "@openzeppelin/contracts/utils/EnumerableSet.sol";
import "../../core/fund/vault/IVault.sol";
import "../utils/ExtensionBase.sol";
import "../utils/FundDeployerOwnerMixin.sol";
import "./IPolicy.sol";
import "./IPolicyManager.sol";

/// @title PolicyManager Contract
/// @author Enzyme Council <security@enzyme.finance>
/// @notice Manages policies for funds
contract PolicyManager is IPolicyManager, ExtensionBase, FundDeployerOwnerMixin {
    using EnumerableSet for EnumerableSet.AddressSet;

    event PolicyDeregistered(address indexed policy, string indexed identifier);

    event PolicyDisabledForFund(address indexed comptrollerProxy, address indexed policy);

    event PolicyEnabledForFund(
        address indexed comptrollerProxy,
        address indexed policy,
        bytes settingsData
    );

    event PolicyRegistered(
        address indexed policy,
        string indexed identifier,
        PolicyHook[] implementedHooks
    );

    EnumerableSet.AddressSet private registeredPolicies;
    mapping(address => mapping(PolicyHook => bool)) private policyToHookToIsImplemented;
    mapping(address => EnumerableSet.AddressSet) private comptrollerProxyToPolicies;

    modifier onlyBuySharesHooks(address _policy) {
        require(
            !policyImplementsHook(_policy, PolicyHook.PreCallOnIntegration) &&
                !policyImplementsHook(_policy, PolicyHook.PostCallOnIntegration),
            "onlyBuySharesHooks: Disallowed hook"
        );
        _;
    }

    modifier onlyEnabledPolicyForFund(address _comptrollerProxy, address _policy) {
        require(
            policyIsEnabledForFund(_comptrollerProxy, _policy),
            "onlyEnabledPolicyForFund: Policy not enabled"
        );
        _;
    }

    constructor(address _fundDeployer) public FundDeployerOwnerMixin(_fundDeployer) {}

    // EXTERNAL FUNCTIONS

    /// @notice Validates and initializes policies as necessary prior to fund activation
    /// @param _isMigratedFund True if the fund is migrating to this release
    /// @dev Caller is expected to be a valid ComptrollerProxy, but there isn't a need to validate.
    function activateForFund(bool _isMigratedFund) external override {
        address vaultProxy = __setValidatedVaultProxy(msg.sender);

        // Policies must assert that they are congruent with migrated vault state
        if (_isMigratedFund) {
            address[] memory enabledPolicies = getEnabledPoliciesForFund(msg.sender);
            for (uint256 i; i < enabledPolicies.length; i++) {
                __activatePolicyForFund(msg.sender, vaultProxy, enabledPolicies[i]);
            }
        }
    }

    /// @notice Deactivates policies for a fund by destroying storage
    function deactivateForFund() external override {
        delete comptrollerProxyToVaultProxy[msg.sender];

        for (uint256 i = comptrollerProxyToPolicies[msg.sender].length(); i > 0; i--) {
            comptrollerProxyToPolicies[msg.sender].remove(
                comptrollerProxyToPolicies[msg.sender].at(i - 1)
            );
        }
    }

    /// @notice Disables a policy for a fund
    /// @param _comptrollerProxy The ComptrollerProxy of the fund
    /// @param _policy The policy address to disable
    function disablePolicyForFund(address _comptrollerProxy, address _policy)
        external
        onlyBuySharesHooks(_policy)
        onlyEnabledPolicyForFund(_comptrollerProxy, _policy)
    {
        __validateIsFundOwner(getVaultProxyForFund(_comptrollerProxy), msg.sender);

        comptrollerProxyToPolicies[_comptrollerProxy].remove(_policy);

        emit PolicyDisabledForFund(_comptrollerProxy, _policy);
    }

    /// @notice Enables a policy for a fund
    /// @param _comptrollerProxy The ComptrollerProxy of the fund
    /// @param _policy The policy address to enable
    /// @param _settingsData The encoded settings data with which to configure the policy
    /// @dev Disabling a policy does not delete fund config on the policy, so if a policy is
    /// disabled and then enabled again, its initial state will be the previous config. It is the
    /// policy's job to determine how to merge that config with the _settingsData param in this function.
    function enablePolicyForFund(
        address _comptrollerProxy,
        address _policy,
        bytes calldata _settingsData
    ) external onlyBuySharesHooks(_policy) {
        address vaultProxy = getVaultProxyForFund(_comptrollerProxy);
        __validateIsFundOwner(vaultProxy, msg.sender);

        __enablePolicyForFund(_comptrollerProxy, _policy, _settingsData);

        __activatePolicyForFund(_comptrollerProxy, vaultProxy, _policy);
    }

    /// @notice Enable policies for use in a fund
    /// @param _configData Encoded config data
    /// @dev Only called during init() on ComptrollerProxy deployment
    function setConfigForFund(bytes calldata _configData) external override {
        (address[] memory policies, bytes[] memory settingsData) = abi.decode(
            _configData,
            (address[], bytes[])
        );

        // Sanity check
        require(
            policies.length == settingsData.length,
            "setConfigForFund: policies and settingsData array lengths unequal"
        );

        // Enable each policy with settings
        for (uint256 i; i < policies.length; i++) {
            __enablePolicyForFund(msg.sender, policies[i], settingsData[i]);
        }
    }

    /// @notice Updates policy settings for a fund
    /// @param _comptrollerProxy The ComptrollerProxy of the fund
    /// @param _policy The Policy contract to update
    /// @param _settingsData The encoded settings data with which to update the policy config
    function updatePolicySettingsForFund(
        address _comptrollerProxy,
        address _policy,
        bytes calldata _settingsData
    ) external onlyBuySharesHooks(_policy) onlyEnabledPolicyForFund(_comptrollerProxy, _policy) {
        address vaultProxy = getVaultProxyForFund(_comptrollerProxy);
        __validateIsFundOwner(vaultProxy, msg.sender);

        IPolicy(_policy).updateFundSettings(_comptrollerProxy, vaultProxy, _settingsData);
    }

    /// @notice Validates all policies that apply to a given hook for a fund
    /// @param _comptrollerProxy The ComptrollerProxy of the fund
    /// @param _hook The PolicyHook for which to validate policies
    /// @param _validationData The encoded data with which to validate the filtered policies
    function validatePolicies(
        address _comptrollerProxy,
        PolicyHook _hook,
        bytes calldata _validationData
    ) external override {
        address vaultProxy = getVaultProxyForFund(_comptrollerProxy);
        address[] memory policies = getEnabledPoliciesForFund(_comptrollerProxy);
        for (uint256 i; i < policies.length; i++) {
            if (!policyImplementsHook(policies[i], _hook)) {
                continue;
            }

            require(
                IPolicy(policies[i]).validateRule(
                    _comptrollerProxy,
                    vaultProxy,
                    _hook,
                    _validationData
                ),
                string(
                    abi.encodePacked(
                        "Rule evaluated to false: ",
                        IPolicy(policies[i]).identifier()
                    )
                )
            );
        }
    }

    // PRIVATE FUNCTIONS

    /// @dev Helper to activate a policy for a fund
    function __activatePolicyForFund(
        address _comptrollerProxy,
        address _vaultProxy,
        address _policy
    ) private {
        IPolicy(_policy).activateForFund(_comptrollerProxy, _vaultProxy);
    }

    /// @dev Helper to set config and enable policies for a fund
    function __enablePolicyForFund(
        address _comptrollerProxy,
        address _policy,
        bytes memory _settingsData
    ) private {
        require(
            !policyIsEnabledForFund(_comptrollerProxy, _policy),
            "__enablePolicyForFund: policy already enabled"
        );
        require(policyIsRegistered(_policy), "__enablePolicyForFund: Policy is not registered");

        // Set fund config on policy
        if (_settingsData.length > 0) {
            IPolicy(_policy).addFundSettings(_comptrollerProxy, _settingsData);
        }

        // Add policy
        comptrollerProxyToPolicies[_comptrollerProxy].add(_policy);

        emit PolicyEnabledForFund(_comptrollerProxy, _policy, _settingsData);
    }

    /// @dev Helper to validate fund owner.
    /// Preferred to a modifier because allows gas savings if re-using _vaultProxy.
    function __validateIsFundOwner(address _vaultProxy, address _who) private view {
        require(
            _who == IVault(_vaultProxy).getOwner(),
            "Only the fund owner can call this function"
        );
    }

    ///////////////////////
    // POLICIES REGISTRY //
    ///////////////////////

    /// @notice Remove policies from the list of registered policies
    /// @param _policies Addresses of policies to be registered
    function deregisterPolicies(address[] calldata _policies) external onlyFundDeployerOwner {
        require(_policies.length > 0, "deregisterPolicies: _policies cannot be empty");

        for (uint256 i; i < _policies.length; i++) {
            require(
                policyIsRegistered(_policies[i]),
                "deregisterPolicies: policy is not registered"
            );

            registeredPolicies.remove(_policies[i]);

            emit PolicyDeregistered(_policies[i], IPolicy(_policies[i]).identifier());
        }
    }

    /// @notice Add policies to the list of registered policies
    /// @param _policies Addresses of policies to be registered
    function registerPolicies(address[] calldata _policies) external onlyFundDeployerOwner {
        require(_policies.length > 0, "registerPolicies: _policies cannot be empty");

        for (uint256 i; i < _policies.length; i++) {
            require(
                !policyIsRegistered(_policies[i]),
                "registerPolicies: policy already registered"
            );

            registeredPolicies.add(_policies[i]);

            // Store the hooks that a policy implements for later use.
            // Fronts the gas for calls to check if a hook is implemented, and guarantees
            // that the implementsHooks return value does not change post-registration.
            IPolicy policyContract = IPolicy(_policies[i]);
            PolicyHook[] memory implementedHooks = policyContract.implementedHooks();
            for (uint256 j; j < implementedHooks.length; j++) {
                policyToHookToIsImplemented[_policies[i]][implementedHooks[j]] = true;
            }

            emit PolicyRegistered(_policies[i], policyContract.identifier(), implementedHooks);
        }
    }

    ///////////////////
    // STATE GETTERS //
    ///////////////////

    /// @notice Get all registered policies
    /// @return registeredPoliciesArray_ A list of all registered policy addresses
    function getRegisteredPolicies()
        external
        view
        returns (address[] memory registeredPoliciesArray_)
    {
        registeredPoliciesArray_ = new address[](registeredPolicies.length());
        for (uint256 i; i < registeredPoliciesArray_.length; i++) {
            registeredPoliciesArray_[i] = registeredPolicies.at(i);
        }
    }

    /// @notice Get a list of enabled policies for a given fund
    /// @param _comptrollerProxy The ComptrollerProxy of the fund
    /// @return enabledPolicies_ An array of enabled policy addresses
    function getEnabledPoliciesForFund(address _comptrollerProxy)
        public
        view
        returns (address[] memory enabledPolicies_)
    {
        enabledPolicies_ = new address[](comptrollerProxyToPolicies[_comptrollerProxy].length());
        for (uint256 i; i < enabledPolicies_.length; i++) {
            enabledPolicies_[i] = comptrollerProxyToPolicies[_comptrollerProxy].at(i);
        }
    }

    /// @notice Checks if a policy implements a particular hook
    /// @param _policy The address of the policy to check
    /// @param _hook The PolicyHook to check
    /// @return implementsHook_ True if the policy implements the hook
    function policyImplementsHook(address _policy, PolicyHook _hook)
        public
        view
        returns (bool implementsHook_)
    {
        return policyToHookToIsImplemented[_policy][_hook];
    }

    /// @notice Check if a policy is enabled for the fund
    /// @param _comptrollerProxy The ComptrollerProxy of the fund to check
    /// @param _policy The address of the policy to check
    /// @return isEnabled_ True if the policy is enabled for the fund
    function policyIsEnabledForFund(address _comptrollerProxy, address _policy)
        public
        view
        returns (bool isEnabled_)
    {
        return comptrollerProxyToPolicies[_comptrollerProxy].contains(_policy);
    }

    /// @notice Check whether a policy is registered
    /// @param _policy The address of the policy to check
    /// @return isRegistered_ True if the policy is registered
    function policyIsRegistered(address _policy) public view returns (bool isRegistered_) {
        return registeredPolicies.contains(_policy);
    }
}

{
  "compilationTarget": {
    "contracts/release/extensions/policy-manager/PolicyManager.sol": "PolicyManager"
  },
  "evmVersion": "istanbul",
  "libraries": {},
  "metadata": {
    "bytecodeHash": "ipfs",
    "useLiteralContent": true
  },
  "optimizer": {
    "details": {
      "constantOptimizer": true,
      "cse": true,
      "deduplicate": true,
      "jumpdestRemover": true,
      "orderLiterals": true,
      "peephole": true,
      "yul": false
    },
    "runs": 200
  },
  "remappings": []
}