// File: @balancer-labs/v2-interfaces/contracts/vault/IVault.sol



// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

pragma experimental ABIEncoderV2;

import "../solidity-utils/openzeppelin/IERC20.sol";
import "../solidity-utils/helpers/IAuthentication.sol";
import "../solidity-utils/helpers/ISignaturesValidator.sol";
import "../solidity-utils/helpers/ITemporarilyPausable.sol";
import "../solidity-utils/misc/IWETH.sol";

import "./IAsset.sol";
import "./IAuthorizer.sol";
import "./IFlashLoanRecipient.sol";
import "./IProtocolFeesCollector.sol";

pragma solidity ^0.7.0;

/**
 * @dev Full external interface for the Vault core contract - no external or public methods exist in the contract that
 * don't override one of these declarations.
 */
interface IVault is ISignaturesValidator, ITemporarilyPausable, IAuthentication {
    // Generalities about the Vault:
    //
    // - Whenever documentation refers to 'tokens', it strictly refers to ERC20-compliant token contracts. Tokens are
    // transferred out of the Vault by calling the `IERC20.transfer` function, and transferred in by calling
    // `IERC20.transferFrom`. In these cases, the sender must have previously allowed the Vault to use their tokens by
    // calling `IERC20.approve`. The only deviation from the ERC20 standard that is supported is functions not returning
    // a boolean value: in these scenarios, a non-reverting call is assumed to be successful.
    //
    // - All non-view functions in the Vault are non-reentrant: calling them while another one is mid-execution (e.g.
    // while execution control is transferred to a token contract during a swap) will result in a revert. View
    // functions can be called in a re-reentrant way, but doing so might cause them to return inconsistent results.
    // Contracts calling view functions in the Vault must make sure the Vault has not already been entered.
    //
    // - View functions revert if referring to either unregistered Pools, or unregistered tokens for registered Pools.

    // Authorizer
    //
    // Some system actions are permissioned, like setting and collecting protocol fees. This permissioning system exists
    // outside of the Vault in the Authorizer contract: the Vault simply calls the Authorizer to check if the caller
    // can perform a given action.

    /**
     * @dev Returns the Vault's Authorizer.
     */
    function getAuthorizer() external view returns (IAuthorizer);

    /**
     * @dev Sets a new Authorizer for the Vault. The caller must be allowed by the current Authorizer to do this.
     *
     * Emits an `AuthorizerChanged` event.
     */
    function setAuthorizer(IAuthorizer newAuthorizer) external;

    /**
     * @dev Emitted when a new authorizer is set by `setAuthorizer`.
     */
    event AuthorizerChanged(IAuthorizer indexed newAuthorizer);

    // Relayers
    //
    // Additionally, it is possible for an account to perform certain actions on behalf of another one, using their
    // Vault ERC20 allowance and Internal Balance. These accounts are said to be 'relayers' for these Vault functions,
    // and are expected to be smart contracts with sound authentication mechanisms. For an account to be able to wield
    // this power, two things must occur:
    //  - The Authorizer must grant the account the permission to be a relayer for the relevant Vault function. This
    //    means that Balancer governance must approve each individual contract to act as a relayer for the intended
    //    functions.
    //  - Each user must approve the relayer to act on their behalf.
    // This double protection means users cannot be tricked into approving malicious relayers (because they will not
    // have been allowed by the Authorizer via governance), nor can malicious relayers approved by a compromised
    // Authorizer or governance drain user funds, since they would also need to be approved by each individual user.

    /**
     * @dev Returns true if `user` has approved `relayer` to act as a relayer for them.
     */
    function hasApprovedRelayer(address user, address relayer) external view returns (bool);

    /**
     * @dev Allows `relayer` to act as a relayer for `sender` if `approved` is true, and disallows it otherwise.
     *
     * Emits a `RelayerApprovalChanged` event.
     */
    function setRelayerApproval(
        address sender,
        address relayer,
        bool approved
    ) external;

    /**
     * @dev Emitted every time a relayer is approved or disapproved by `setRelayerApproval`.
     */
    event RelayerApprovalChanged(address indexed relayer, address indexed sender, bool approved);

    // Internal Balance
    //
    // Users can deposit tokens into the Vault, where they are allocated to their Internal Balance, and later
    // transferred or withdrawn. It can also be used as a source of tokens when joining Pools, as a destination
    // when exiting them, and as either when performing swaps. This usage of Internal Balance results in greatly reduced
    // gas costs when compared to relying on plain ERC20 transfers, leading to large savings for frequent users.
    //
    // Internal Balance management features batching, which means a single contract call can be used to perform multiple
    // operations of different kinds, with different senders and recipients, at once.

    /**
     * @dev Returns `user`'s Internal Balance for a set of tokens.
     */
    function getInternalBalance(address user, IERC20[] memory tokens) external view returns (uint256[] memory);

    /**
     * @dev Performs a set of user balance operations, which involve Internal Balance (deposit, withdraw or transfer)
     * and plain ERC20 transfers using the Vault's allowance. This last feature is particularly useful for relayers, as
     * it lets integrators reuse a user's Vault allowance.
     *
     * For each operation, if the caller is not `sender`, it must be an authorized relayer for them.
     */
    function manageUserBalance(UserBalanceOp[] memory ops) external payable;

    /**
     * @dev Data for `manageUserBalance` operations, which include the possibility for ETH to be sent and received
     without manual WETH wrapping or unwrapping.
     */
    struct UserBalanceOp {
        UserBalanceOpKind kind;
        IAsset asset;
        uint256 amount;
        address sender;
        address payable recipient;
    }

    // There are four possible operations in `manageUserBalance`:
    //
    // - DEPOSIT_INTERNAL
    // Increases the Internal Balance of the `recipient` account by transferring tokens from the corresponding
    // `sender`. The sender must have allowed the Vault to use their tokens via `IERC20.approve()`.
    //
    // ETH can be used by passing the ETH sentinel value as the asset and forwarding ETH in the call: it will be wrapped
    // and deposited as WETH. Any ETH amount remaining will be sent back to the caller (not the sender, which is
    // relevant for relayers).
    //
    // Emits an `InternalBalanceChanged` event.
    //
    //
    // - WITHDRAW_INTERNAL
    // Decreases the Internal Balance of the `sender` account by transferring tokens to the `recipient`.
    //
    // ETH can be used by passing the ETH sentinel value as the asset. This will deduct WETH instead, unwrap it and send
    // it to the recipient as ETH.
    //
    // Emits an `InternalBalanceChanged` event.
    //
    //
    // - TRANSFER_INTERNAL
    // Transfers tokens from the Internal Balance of the `sender` account to the Internal Balance of `recipient`.
    //
    // Reverts if the ETH sentinel value is passed.
    //
    // Emits an `InternalBalanceChanged` event.
    //
    //
    // - TRANSFER_EXTERNAL
    // Transfers tokens from `sender` to `recipient`, using the Vault's ERC20 allowance. This is typically used by
    // relayers, as it lets them reuse a user's Vault allowance.
    //
    // Reverts if the ETH sentinel value is passed.
    //
    // Emits an `ExternalBalanceTransfer` event.

    enum UserBalanceOpKind { DEPOSIT_INTERNAL, WITHDRAW_INTERNAL, TRANSFER_INTERNAL, TRANSFER_EXTERNAL }

    /**
     * @dev Emitted when a user's Internal Balance changes, either from calls to `manageUserBalance`, or through
     * interacting with Pools using Internal Balance.
     *
     * Because Internal Balance works exclusively with ERC20 tokens, ETH deposits and withdrawals will use the WETH
     * address.
     */
    event InternalBalanceChanged(address indexed user, IERC20 indexed token, int256 delta);

    /**
     * @dev Emitted when a user's Vault ERC20 allowance is used by the Vault to transfer tokens to an external account.
     */
    event ExternalBalanceTransfer(IERC20 indexed token, address indexed sender, address recipient, uint256 amount);

    // Pools
    //
    // There are three specialization settings for Pools, which allow for cheaper swaps at the cost of reduced
    // functionality:
    //
    //  - General: no specialization, suited for all Pools. IGeneralPool is used for swap request callbacks, passing the
    // balance of all tokens in the Pool. These Pools have the largest swap costs (because of the extra storage reads),
    // which increase with the number of registered tokens.
    //
    //  - Minimal Swap Info: IMinimalSwapInfoPool is used instead of IGeneralPool, which saves gas by only passing the
    // balance of the two tokens involved in the swap. This is suitable for some pricing algorithms, like the weighted
    // constant product one popularized by Balancer V1. Swap costs are smaller compared to general Pools, and are
    // independent of the number of registered tokens.
    //
    //  - Two Token: only allows two tokens to be registered. This achieves the lowest possible swap gas cost. Like
    // minimal swap info Pools, these are called via IMinimalSwapInfoPool.

    enum PoolSpecialization { GENERAL, MINIMAL_SWAP_INFO, TWO_TOKEN }

    /**
     * @dev Registers the caller account as a Pool with a given specialization setting. Returns the Pool's ID, which
     * is used in all Pool-related functions. Pools cannot be deregistered, nor can the Pool's specialization be
     * changed.
     *
     * The caller is expected to be a smart contract that implements either `IGeneralPool` or `IMinimalSwapInfoPool`,
     * depending on the chosen specialization setting. This contract is known as the Pool's contract.
     *
     * Note that the same contract may register itself as multiple Pools with unique Pool IDs, or in other words,
     * multiple Pools may share the same contract.
     *
     * Emits a `PoolRegistered` event.
     */
    function registerPool(PoolSpecialization specialization) external returns (bytes32);

    /**
     * @dev Emitted when a Pool is registered by calling `registerPool`.
     */
    event PoolRegistered(bytes32 indexed poolId, address indexed poolAddress, PoolSpecialization specialization);

    /**
     * @dev Returns a Pool's contract address and specialization setting.
     */
    function getPool(bytes32 poolId) external view returns (address, PoolSpecialization);

    /**
     * @dev Registers `tokens` for the `poolId` Pool. Must be called by the Pool's contract.
     *
     * Pools can only interact with tokens they have registered. Users join a Pool by transferring registered tokens,
     * exit by receiving registered tokens, and can only swap registered tokens.
     *
     * Each token can only be registered once. For Pools with the Two Token specialization, `tokens` must have a length
     * of two, that is, both tokens must be registered in the same `registerTokens` call, and they must be sorted in
     * ascending order.
     *
     * The `tokens` and `assetManagers` arrays must have the same length, and each entry in these indicates the Asset
     * Manager for the corresponding token. Asset Managers can manage a Pool's tokens via `managePoolBalance`,
     * depositing and withdrawing them directly, and can even set their balance to arbitrary amounts. They are therefore
     * expected to be highly secured smart contracts with sound design principles, and the decision to register an
     * Asset Manager should not be made lightly.
     *
     * Pools can choose not to assign an Asset Manager to a given token by passing in the zero address. Once an Asset
     * Manager is set, it cannot be changed except by deregistering the associated token and registering again with a
     * different Asset Manager.
     *
     * Emits a `TokensRegistered` event.
     */
    function registerTokens(
        bytes32 poolId,
        IERC20[] memory tokens,
        address[] memory assetManagers
    ) external;

    /**
     * @dev Emitted when a Pool registers tokens by calling `registerTokens`.
     */
    event TokensRegistered(bytes32 indexed poolId, IERC20[] tokens, address[] assetManagers);

    /**
     * @dev Deregisters `tokens` for the `poolId` Pool. Must be called by the Pool's contract.
     *
     * Only registered tokens (via `registerTokens`) can be deregistered. Additionally, they must have zero total
     * balance. For Pools with the Two Token specialization, `tokens` must have a length of two, that is, both tokens
     * must be deregistered in the same `deregisterTokens` call.
     *
     * A deregistered token can be re-registered later on, possibly with a different Asset Manager.
     *
     * Emits a `TokensDeregistered` event.
     */
    function deregisterTokens(bytes32 poolId, IERC20[] memory tokens) external;

    /**
     * @dev Emitted when a Pool deregisters tokens by calling `deregisterTokens`.
     */
    event TokensDeregistered(bytes32 indexed poolId, IERC20[] tokens);

    /**
     * @dev Returns detailed information for a Pool's registered token.
     *
     * `cash` is the number of tokens the Vault currently holds for the Pool. `managed` is the number of tokens
     * withdrawn and held outside the Vault by the Pool's token Asset Manager. The Pool's total balance for `token`
     * equals the sum of `cash` and `managed`.
     *
     * Internally, `cash` and `managed` are stored using 112 bits. No action can ever cause a Pool's token `cash`,
     * `managed` or `total` balance to be greater than 2^112 - 1.
     *
     * `lastChangeBlock` is the number of the block in which `token`'s total balance was last modified (via either a
     * join, exit, swap, or Asset Manager update). This value is useful to avoid so-called 'sandwich attacks', for
     * example when developing price oracles. A change of zero (e.g. caused by a swap with amount zero) is considered a
     * change for this purpose, and will update `lastChangeBlock`.
     *
     * `assetManager` is the Pool's token Asset Manager.
     */
    function getPoolTokenInfo(bytes32 poolId, IERC20 token)
        external
        view
        returns (
            uint256 cash,
            uint256 managed,
            uint256 lastChangeBlock,
            address assetManager
        );

    /**
     * @dev Returns a Pool's registered tokens, the total balance for each, and the latest block when *any* of
     * the tokens' `balances` changed.
     *
     * The order of the `tokens` array is the same order that will be used in `joinPool`, `exitPool`, as well as in all
     * Pool hooks (where applicable). Calls to `registerTokens` and `deregisterTokens` may change this order.
     *
     * If a Pool only registers tokens once, and these are sorted in ascending order, they will be stored in the same
     * order as passed to `registerTokens`.
     *
     * Total balances include both tokens held by the Vault and those withdrawn by the Pool's Asset Managers. These are
     * the amounts used by joins, exits and swaps. For a detailed breakdown of token balances, use `getPoolTokenInfo`
     * instead.
     */
    function getPoolTokens(bytes32 poolId)
        external
        view
        returns (
            IERC20[] memory tokens,
            uint256[] memory balances,
            uint256 lastChangeBlock
        );

    /**
     * @dev Called by users to join a Pool, which transfers tokens from `sender` into the Pool's balance. This will
     * trigger custom Pool behavior, which will typically grant something in return to `recipient` - often tokenized
     * Pool shares.
     *
     * If the caller is not `sender`, it must be an authorized relayer for them.
     *
     * The `assets` and `maxAmountsIn` arrays must have the same length, and each entry indicates the maximum amount
     * to send for each asset. The amounts to send are decided by the Pool and not the Vault: it just enforces
     * these maximums.
     *
     * If joining a Pool that holds WETH, it is possible to send ETH directly: the Vault will do the wrapping. To enable
     * this mechanism, the IAsset sentinel value (the zero address) must be passed in the `assets` array instead of the
     * WETH address. Note that it is not possible to combine ETH and WETH in the same join. Any excess ETH will be sent
     * back to the caller (not the sender, which is important for relayers).
     *
     * `assets` must have the same length and order as the array returned by `getPoolTokens`. This prevents issues when
     * interacting with Pools that register and deregister tokens frequently. If sending ETH however, the array must be
     * sorted *before* replacing the WETH address with the ETH sentinel value (the zero address), which means the final
     * `assets` array might not be sorted. Pools with no registered tokens cannot be joined.
     *
     * If `fromInternalBalance` is true, the caller's Internal Balance will be preferred: ERC20 transfers will only
     * be made for the difference between the requested amount and Internal Balance (if any). Note that ETH cannot be
     * withdrawn from Internal Balance: attempting to do so will trigger a revert.
     *
     * This causes the Vault to call the `IBasePool.onJoinPool` hook on the Pool's contract, where Pools implement
     * their own custom logic. This typically requires additional information from the user (such as the expected number
     * of Pool shares). This can be encoded in the `userData` argument, which is ignored by the Vault and passed
     * directly to the Pool's contract, as is `recipient`.
     *
     * Emits a `PoolBalanceChanged` event.
     */
    function joinPool(
        bytes32 poolId,
        address sender,
        address recipient,
        JoinPoolRequest memory request
    ) external payable;

    struct JoinPoolRequest {
        IAsset[] assets;
        uint256[] maxAmountsIn;
        bytes userData;
        bool fromInternalBalance;
    }

    /**
     * @dev Called by users to exit a Pool, which transfers tokens from the Pool's balance to `recipient`. This will
     * trigger custom Pool behavior, which will typically ask for something in return from `sender` - often tokenized
     * Pool shares. The amount of tokens that can be withdrawn is limited by the Pool's `cash` balance (see
     * `getPoolTokenInfo`).
     *
     * If the caller is not `sender`, it must be an authorized relayer for them.
     *
     * The `tokens` and `minAmountsOut` arrays must have the same length, and each entry in these indicates the minimum
     * token amount to receive for each token contract. The amounts to send are decided by the Pool and not the Vault:
     * it just enforces these minimums.
     *
     * If exiting a Pool that holds WETH, it is possible to receive ETH directly: the Vault will do the unwrapping. To
     * enable this mechanism, the IAsset sentinel value (the zero address) must be passed in the `assets` array instead
     * of the WETH address. Note that it is not possible to combine ETH and WETH in the same exit.
     *
     * `assets` must have the same length and order as the array returned by `getPoolTokens`. This prevents issues when
     * interacting with Pools that register and deregister tokens frequently. If receiving ETH however, the array must
     * be sorted *before* replacing the WETH address with the ETH sentinel value (the zero address), which means the
     * final `assets` array might not be sorted. Pools with no registered tokens cannot be exited.
     *
     * If `toInternalBalance` is true, the tokens will be deposited to `recipient`'s Internal Balance. Otherwise,
     * an ERC20 transfer will be performed. Note that ETH cannot be deposited to Internal Balance: attempting to
     * do so will trigger a revert.
     *
     * `minAmountsOut` is the minimum amount of tokens the user expects to get out of the Pool, for each token in the
     * `tokens` array. This array must match the Pool's registered tokens.
     *
     * This causes the Vault to call the `IBasePool.onExitPool` hook on the Pool's contract, where Pools implement
     * their own custom logic. This typically requires additional information from the user (such as the expected number
     * of Pool shares to return). This can be encoded in the `userData` argument, which is ignored by the Vault and
     * passed directly to the Pool's contract.
     *
     * Emits a `PoolBalanceChanged` event.
     */
    function exitPool(
        bytes32 poolId,
        address sender,
        address payable recipient,
        ExitPoolRequest memory request
    ) external;

    struct ExitPoolRequest {
        IAsset[] assets;
        uint256[] minAmountsOut;
        bytes userData;
        bool toInternalBalance;
    }

    /**
     * @dev Emitted when a user joins or exits a Pool by calling `joinPool` or `exitPool`, respectively.
     */
    event PoolBalanceChanged(
        bytes32 indexed poolId,
        address indexed liquidityProvider,
        IERC20[] tokens,
        int256[] deltas,
        uint256[] protocolFeeAmounts
    );

    enum PoolBalanceChangeKind { JOIN, EXIT }

    // Swaps
    //
    // Users can swap tokens with Pools by calling the `swap` and `batchSwap` functions. To do this,
    // they need not trust Pool contracts in any way: all security checks are made by the Vault. They must however be
    // aware of the Pools' pricing algorithms in order to estimate the prices Pools will quote.
    //
    // The `swap` function executes a single swap, while `batchSwap` can perform multiple swaps in sequence.
    // In each individual swap, tokens of one kind are sent from the sender to the Pool (this is the 'token in'),
    // and tokens of another kind are sent from the Pool to the recipient in exchange (this is the 'token out').
    // More complex swaps, such as one token in to multiple tokens out can be achieved by batching together
    // individual swaps.
    //
    // There are two swap kinds:
    //  - 'given in' swaps, where the amount of tokens in (sent to the Pool) is known, and the Pool determines (via the
    // `onSwap` hook) the amount of tokens out (to send to the recipient).
    //  - 'given out' swaps, where the amount of tokens out (received from the Pool) is known, and the Pool determines
    // (via the `onSwap` hook) the amount of tokens in (to receive from the sender).
    //
    // Additionally, it is possible to chain swaps using a placeholder input amount, which the Vault replaces with
    // the calculated output of the previous swap. If the previous swap was 'given in', this will be the calculated
    // tokenOut amount. If the previous swap was 'given out', it will use the calculated tokenIn amount. These extended
    // swaps are known as 'multihop' swaps, since they 'hop' through a number of intermediate tokens before arriving at
    // the final intended token.
    //
    // In all cases, tokens are only transferred in and out of the Vault (or withdrawn from and deposited into Internal
    // Balance) after all individual swaps have been completed, and the net token balance change computed. This makes
    // certain swap patterns, such as multihops, or swaps that interact with the same token pair in multiple Pools, cost
    // much less gas than they would otherwise.
    //
    // It also means that under certain conditions it is possible to perform arbitrage by swapping with multiple
    // Pools in a way that results in net token movement out of the Vault (profit), with no tokens being sent in (only
    // updating the Pool's internal accounting).
    //
    // To protect users from front-running or the market changing rapidly, they supply a list of 'limits' for each token
    // involved in the swap, where either the maximum number of tokens to send (by passing a positive value) or the
    // minimum amount of tokens to receive (by passing a negative value) is specified.
    //
    // Additionally, a 'deadline' timestamp can also be provided, forcing the swap to fail if it occurs after
    // this point in time (e.g. if the transaction failed to be included in a block promptly).
    //
    // If interacting with Pools that hold WETH, it is possible to both send and receive ETH directly: the Vault will do
    // the wrapping and unwrapping. To enable this mechanism, the IAsset sentinel value (the zero address) must be
    // passed in the `assets` array instead of the WETH address. Note that it is possible to combine ETH and WETH in the
    // same swap. Any excess ETH will be sent back to the caller (not the sender, which is relevant for relayers).
    //
    // Finally, Internal Balance can be used when either sending or receiving tokens.

    enum SwapKind { GIVEN_IN, GIVEN_OUT }

    /**
     * @dev Performs a swap with a single Pool.
     *
     * If the swap is 'given in' (the number of tokens to send to the Pool is known), it returns the amount of tokens
     * taken from the Pool, which must be greater than or equal to `limit`.
     *
     * If the swap is 'given out' (the number of tokens to take from the Pool is known), it returns the amount of tokens
     * sent to the Pool, which must be less than or equal to `limit`.
     *
     * Internal Balance usage and the recipient are determined by the `funds` struct.
     *
     * Emits a `Swap` event.
     */
    function swap(
        SingleSwap memory singleSwap,
        FundManagement memory funds,
        uint256 limit,
        uint256 deadline
    ) external payable returns (uint256);

    /**
     * @dev Data for a single swap executed by `swap`. `amount` is either `amountIn` or `amountOut` depending on
     * the `kind` value.
     *
     * `assetIn` and `assetOut` are either token addresses, or the IAsset sentinel value for ETH (the zero address).
     * Note that Pools never interact with ETH directly: it will be wrapped to or unwrapped from WETH by the Vault.
     *
     * The `userData` field is ignored by the Vault, but forwarded to the Pool in the `onSwap` hook, and may be
     * used to extend swap behavior.
     */
    struct SingleSwap {
        bytes32 poolId;
        SwapKind kind;
        IAsset assetIn;
        IAsset assetOut;
        uint256 amount;
        bytes userData;
    }

    /**
     * @dev Performs a series of swaps with one or multiple Pools. In each individual swap, the caller determines either
     * the amount of tokens sent to or received from the Pool, depending on the `kind` value.
     *
     * Returns an array with the net Vault asset balance deltas. Positive amounts represent tokens (or ETH) sent to the
     * Vault, and negative amounts represent tokens (or ETH) sent by the Vault. Each delta corresponds to the asset at
     * the same index in the `assets` array.
     *
     * Swaps are executed sequentially, in the order specified by the `swaps` array. Each array element describes a
     * Pool, the token to be sent to this Pool, the token to receive from it, and an amount that is either `amountIn` or
     * `amountOut` depending on the swap kind.
     *
     * Multihop swaps can be executed by passing an `amount` value of zero for a swap. This will cause the amount in/out
     * of the previous swap to be used as the amount in for the current one. In a 'given in' swap, 'tokenIn' must equal
     * the previous swap's `tokenOut`. For a 'given out' swap, `tokenOut` must equal the previous swap's `tokenIn`.
     *
     * The `assets` array contains the addresses of all assets involved in the swaps. These are either token addresses,
     * or the IAsset sentinel value for ETH (the zero address). Each entry in the `swaps` array specifies tokens in and
     * out by referencing an index in `assets`. Note that Pools never interact with ETH directly: it will be wrapped to
     * or unwrapped from WETH by the Vault.
     *
     * Internal Balance usage, sender, and recipient are determined by the `funds` struct. The `limits` array specifies
     * the minimum or maximum amount of each token the vault is allowed to transfer.
     *
     * `batchSwap` can be used to make a single swap, like `swap` does, but doing so requires more gas than the
     * equivalent `swap` call.
     *
     * Emits `Swap` events.
     */
    function batchSwap(
        SwapKind kind,
        BatchSwapStep[] memory swaps,
        IAsset[] memory assets,
        FundManagement memory funds,
        int256[] memory limits,
        uint256 deadline
    ) external payable returns (int256[] memory);

    /**
     * @dev Data for each individual swap executed by `batchSwap`. The asset in and out fields are indexes into the
     * `assets` array passed to that function, and ETH assets are converted to WETH.
     *
     * If `amount` is zero, the multihop mechanism is used to determine the actual amount based on the amount in/out
     * from the previous swap, depending on the swap kind.
     *
     * The `userData` field is ignored by the Vault, but forwarded to the Pool in the `onSwap` hook, and may be
     * used to extend swap behavior.
     */
    struct BatchSwapStep {
        bytes32 poolId;
        uint256 assetInIndex;
        uint256 assetOutIndex;
        uint256 amount;
        bytes userData;
    }

    /**
     * @dev Emitted for each individual swap performed by `swap` or `batchSwap`.
     */
    event Swap(
        bytes32 indexed poolId,
        IERC20 indexed tokenIn,
        IERC20 indexed tokenOut,
        uint256 amountIn,
        uint256 amountOut
    );

    /**
     * @dev All tokens in a swap are either sent from the `sender` account to the Vault, or from the Vault to the
     * `recipient` account.
     *
     * If the caller is not `sender`, it must be an authorized relayer for them.
     *
     * If `fromInternalBalance` is true, the `sender`'s Internal Balance will be preferred, performing an ERC20
     * transfer for the difference between the requested amount and the User's Internal Balance (if any). The `sender`
     * must have allowed the Vault to use their tokens via `IERC20.approve()`. This matches the behavior of
     * `joinPool`.
     *
     * If `toInternalBalance` is true, tokens will be deposited to `recipient`'s internal balance instead of
     * transferred. This matches the behavior of `exitPool`.
     *
     * Note that ETH cannot be deposited to or withdrawn from Internal Balance: attempting to do so will trigger a
     * revert.
     */
    struct FundManagement {
        address sender;
        bool fromInternalBalance;
        address payable recipient;
        bool toInternalBalance;
    }

    /**
     * @dev Simulates a call to `batchSwap`, returning an array of Vault asset deltas. Calls to `swap` cannot be
     * simulated directly, but an equivalent `batchSwap` call can and will yield the exact same result.
     *
     * Each element in the array corresponds to the asset at the same index, and indicates the number of tokens (or ETH)
     * the Vault would take from the sender (if positive) or send to the recipient (if negative). The arguments it
     * receives are the same that an equivalent `batchSwap` call would receive.
     *
     * Unlike `batchSwap`, this function performs no checks on the sender or recipient field in the `funds` struct.
     * This makes it suitable to be called by off-chain applications via eth_call without needing to hold tokens,
     * approve them for the Vault, or even know a user's address.
     *
     * Note that this function is not 'view' (due to implementation details): the client code must explicitly execute
     * eth_call instead of eth_sendTransaction.
     */
    function queryBatchSwap(
        SwapKind kind,
        BatchSwapStep[] memory swaps,
        IAsset[] memory assets,
        FundManagement memory funds
    ) external returns (int256[] memory assetDeltas);

    // Flash Loans

    /**
     * @dev Performs a 'flash loan', sending tokens to `recipient`, executing the `receiveFlashLoan` hook on it,
     * and then reverting unless the tokens plus a proportional protocol fee have been returned.
     *
     * The `tokens` and `amounts` arrays must have the same length, and each entry in these indicates the loan amount
     * for each token contract. `tokens` must be sorted in ascending order.
     *
     * The 'userData' field is ignored by the Vault, and forwarded as-is to `recipient` as part of the
     * `receiveFlashLoan` call.
     *
     * Emits `FlashLoan` events.
     */
    function flashLoan(
        IFlashLoanRecipient recipient,
        IERC20[] memory tokens,
        uint256[] memory amounts,
        bytes memory userData
    ) external;

    /**
     * @dev Emitted for each individual flash loan performed by `flashLoan`.
     */
    event FlashLoan(IFlashLoanRecipient indexed recipient, IERC20 indexed token, uint256 amount, uint256 feeAmount);

    // Asset Management
    //
    // Each token registered for a Pool can be assigned an Asset Manager, which is able to freely withdraw the Pool's
    // tokens from the Vault, deposit them, or assign arbitrary values to its `managed` balance (see
    // `getPoolTokenInfo`). This makes them extremely powerful and dangerous. Even if an Asset Manager only directly
    // controls one of the tokens in a Pool, a malicious manager could set that token's balance to manipulate the
    // prices of the other tokens, and then drain the Pool with swaps. The risk of using Asset Managers is therefore
    // not constrained to the tokens they are managing, but extends to the entire Pool's holdings.
    //
    // However, a properly designed Asset Manager smart contract can be safely used for the Pool's benefit,
    // for example by lending unused tokens out for interest, or using them to participate in voting protocols.
    //
    // This concept is unrelated to the IAsset interface.

    /**
     * @dev Performs a set of Pool balance operations, which may be either withdrawals, deposits or updates.
     *
     * Pool Balance management features batching, which means a single contract call can be used to perform multiple
     * operations of different kinds, with different Pools and tokens, at once.
     *
     * For each operation, the caller must be registered as the Asset Manager for `token` in `poolId`.
     */
    function managePoolBalance(PoolBalanceOp[] memory ops) external;

    struct PoolBalanceOp {
        PoolBalanceOpKind kind;
        bytes32 poolId;
        IERC20 token;
        uint256 amount;
    }

    /**
     * Withdrawals decrease the Pool's cash, but increase its managed balance, leaving the total balance unchanged.
     *
     * Deposits increase the Pool's cash, but decrease its managed balance, leaving the total balance unchanged.
     *
     * Updates don't affect the Pool's cash balance, but because the managed balance changes, it does alter the total.
     * The external amount can be either increased or decreased by this call (i.e., reporting a gain or a loss).
     */
    enum PoolBalanceOpKind { WITHDRAW, DEPOSIT, UPDATE }

    /**
     * @dev Emitted when a Pool's token Asset Manager alters its balance via `managePoolBalance`.
     */
    event PoolBalanceManaged(
        bytes32 indexed poolId,
        address indexed assetManager,
        IERC20 indexed token,
        int256 cashDelta,
        int256 managedDelta
    );

    // Protocol Fees
    //
    // Some operations cause the Vault to collect tokens in the form of protocol fees, which can then be withdrawn by
    // permissioned accounts.
    //
    // There are two kinds of protocol fees:
    //
    //  - flash loan fees: charged on all flash loans, as a percentage of the amounts lent.
    //
    //  - swap fees: a percentage of the fees charged by Pools when performing swaps. For a number of reasons, including
    // swap gas costs and interface simplicity, protocol swap fees are not charged on each individual swap. Rather,
    // Pools are expected to keep track of how much they have charged in swap fees, and pay any outstanding debts to the
    // Vault when they are joined or exited. This prevents users from joining a Pool with unpaid debt, as well as
    // exiting a Pool in debt without first paying their share.

    /**
     * @dev Returns the current protocol fee module.
     */
    function getProtocolFeesCollector() external view returns (IProtocolFeesCollector);

    /**
     * @dev Safety mechanism to pause most Vault operations in the event of an emergency - typically detection of an
     * error in some part of the system.
     *
     * The Vault can only be paused during an initial time period, after which pausing is forever disabled.
     *
     * While the contract is paused, the following features are disabled:
     * - depositing and transferring internal balance
     * - transferring external balance (using the Vault's allowance)
     * - swaps
     * - joining Pools
     * - Asset Manager interactions
     *
     * Internal Balance can still be withdrawn, and Pools exited.
     */
    function setPaused(bool paused) external;

    /**
     * @dev Returns the Vault's WETH instance.
     */
    function WETH() external view returns (IWETH);
    // solhint-disable-previous-line func-name-mixedcase
}

// File: @balancer-labs/v2-solidity-utils/contracts/openzeppelin/ReentrancyGuard.sol



// SPDX-License-Identifier: MIT

// Based on the ReentrancyGuard library from OpenZeppelin Contracts, altered to reduce bytecode size.
// Modifier code is inlined by the compiler, which causes its code to appear multiple times in the codebase. By using
// private functions, we achieve the same end result with slightly higher runtime gas costs, but reduced bytecode size.

pragma solidity ^0.7.0;

import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";

/**
 * @dev Contract module that helps prevent reentrant calls to a function.
 *
 * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
 * available, which can be applied to functions to make sure there are no nested
 * (reentrant) calls to them.
 *
 * Note that because there is a single `nonReentrant` guard, functions marked as
 * `nonReentrant` may not call one another. This can be worked around by making
 * those functions `private`, and then adding `external` `nonReentrant` entry
 * points to them.
 *
 * TIP: If you would like to learn more about reentrancy and alternative ways
 * to protect against it, check out our blog post
 * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
 */
abstract contract ReentrancyGuard {
    // Booleans are more expensive than uint256 or any type that takes up a full
    // word because each write operation emits an extra SLOAD to first read the
    // slot's contents, replace the bits taken up by the boolean, and then write
    // back. This is the compiler's defense against contract upgrades and
    // pointer aliasing, and it cannot be disabled.

    // The values being non-zero value makes deployment a bit more expensive,
    // but in exchange the refund on every call to nonReentrant will be lower in
    // amount. Since refunds are capped to a percentage of the total
    // transaction's gas, it is best to keep them low in cases like this one, to
    // increase the likelihood of the full refund coming into effect.
    uint256 private constant _NOT_ENTERED = 1;
    uint256 private constant _ENTERED = 2;

    uint256 private _status;

    constructor() {
        _status = _NOT_ENTERED;
    }

    /**
     * @dev Prevents a contract from calling itself, directly or indirectly.
     * Calling a `nonReentrant` function from another `nonReentrant`
     * function is not supported. It is possible to prevent this from happening
     * by making the `nonReentrant` function external, and make it call a
     * `private` function that does the actual work.
     */
    modifier nonReentrant() {
        _enterNonReentrant();
        _;
        _exitNonReentrant();
    }

    function _enterNonReentrant() private {
        // On the first call to nonReentrant, _status will be _NOT_ENTERED
        _require(_status != _ENTERED, Errors.REENTRANCY);

        // Any calls to nonReentrant after this point will fail
        _status = _ENTERED;
    }

    function _exitNonReentrant() private {
        // By storing the original value once again, a refund is triggered (see
        // https://eips.ethereum.org/EIPS/eip-2200)
        _status = _NOT_ENTERED;
    }
}

// File: @balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/IAuthentication.sol



// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

pragma solidity ^0.7.0;

interface IAuthentication {
    /**
     * @dev Returns the action identifier associated with the external function described by `selector`.
     */
    function getActionId(bytes4 selector) external view returns (bytes32);
}

// File: @balancer-labs/v2-interfaces/contracts/solidity-utils/openzeppelin/IERC20.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.7.0;

/**
 * @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: @balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/ISignaturesValidator.sol



// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

pragma solidity ^0.7.0;

/**
 * @dev Interface for the SignatureValidator helper, used to support meta-transactions.
 */
interface ISignaturesValidator {
    /**
     * @dev Returns the EIP712 domain separator.
     */
    function getDomainSeparator() external view returns (bytes32);

    /**
     * @dev Returns the next nonce used by an address to sign messages.
     */
    function getNextNonce(address user) external view returns (uint256);
}

// File: @balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/ITemporarilyPausable.sol



// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

pragma solidity ^0.7.0;

/**
 * @dev Interface for the TemporarilyPausable helper.
 */
interface ITemporarilyPausable {
    /**
     * @dev Emitted every time the pause state changes by `_setPaused`.
     */
    event PausedStateChanged(bool paused);

    /**
     * @dev Returns the current paused state.
     */
    function getPausedState()
        external
        view
        returns (
            bool paused,
            uint256 pauseWindowEndTime,
            uint256 bufferPeriodEndTime
        );
}

// File: @balancer-labs/v2-interfaces/contracts/solidity-utils/misc/IWETH.sol



// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

pragma solidity ^0.7.0;

import "../openzeppelin/IERC20.sol";

/**
 * @dev Interface for WETH9.
 * See https://github.com/gnosis/canonical-weth/blob/0dd1ea3e295eef916d0c6223ec63141137d22d67/contracts/WETH9.sol
 */
interface IWETH is IERC20 {
    function deposit() external payable;

    function withdraw(uint256 amount) external;
}

// File: @balancer-labs/v2-interfaces/contracts/vault/IAsset.sol



// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

pragma solidity ^0.7.0;

/**
 * @dev This is an empty interface used to represent either ERC20-conforming token contracts or ETH (using the zero
 * address sentinel value). We're just relying on the fact that `interface` can be used to declare new address-like
 * types.
 *
 * This concept is unrelated to a Pool's Asset Managers.
 */
interface IAsset {
    // solhint-disable-previous-line no-empty-blocks
}

// File: @balancer-labs/v2-interfaces/contracts/vault/IAuthorizer.sol



// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

pragma solidity ^0.7.0;

interface IAuthorizer {
    /**
     * @dev Returns true if `account` can perform the action described by `actionId` in the contract `where`.
     */
    function canPerform(
        bytes32 actionId,
        address account,
        address where
    ) external view returns (bool);
}

// File: @balancer-labs/v2-interfaces/contracts/vault/IFlashLoanRecipient.sol



// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

pragma solidity ^0.7.0;

// Inspired by Aave Protocol's IFlashLoanReceiver.

import "../solidity-utils/openzeppelin/IERC20.sol";

interface IFlashLoanRecipient {
    /**
     * @dev When `flashLoan` is called on the Vault, it invokes the `receiveFlashLoan` hook on the recipient.
     *
     * At the time of the call, the Vault will have transferred `amounts` for `tokens` to the recipient. Before this
     * call returns, the recipient must have transferred `amounts` plus `feeAmounts` for each token back to the
     * Vault, or else the entire flash loan will revert.
     *
     * `userData` is the same value passed in the `IVault.flashLoan` call.
     */
    function receiveFlashLoan(
        IERC20[] memory tokens,
        uint256[] memory amounts,
        uint256[] memory feeAmounts,
        bytes memory userData
    ) external;
}

// File: @balancer-labs/v2-interfaces/contracts/vault/IProtocolFeesCollector.sol



// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

pragma solidity ^0.7.0;
pragma experimental ABIEncoderV2;

import "../solidity-utils/openzeppelin/IERC20.sol";

import "./IVault.sol";
import "./IAuthorizer.sol";

interface IProtocolFeesCollector {
    event SwapFeePercentageChanged(uint256 newSwapFeePercentage);
    event FlashLoanFeePercentageChanged(uint256 newFlashLoanFeePercentage);

    function withdrawCollectedFees(
        IERC20[] calldata tokens,
        uint256[] calldata amounts,
        address recipient
    ) external;

    function setSwapFeePercentage(uint256 newSwapFeePercentage) external;

    function setFlashLoanFeePercentage(uint256 newFlashLoanFeePercentage) external;

    function getSwapFeePercentage() external view returns (uint256);

    function getFlashLoanFeePercentage() external view returns (uint256);

    function getCollectedFeeAmounts(IERC20[] memory tokens) external view returns (uint256[] memory feeAmounts);

    function getAuthorizer() external view returns (IAuthorizer);

    function vault() external view returns (IVault);
}

// File: @balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol



// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

pragma solidity ^0.7.0;

// solhint-disable

/**
 * @dev Reverts if `condition` is false, with a revert reason containing `errorCode`. Only codes up to 999 are
 * supported.
 */
function _require(bool condition, uint256 errorCode) pure {
    if (!condition) _revert(errorCode);
}

/**
 * @dev Reverts with a revert reason containing `errorCode`. Only codes up to 999 are supported.
 */
function _revert(uint256 errorCode) pure {
    // We're going to dynamically create a revert string based on the error code, with the following format:
    // 'BAL#{errorCode}'
    // where the code is left-padded with zeroes to three digits (so they range from 000 to 999).
    //
    // We don't have revert strings embedded in the contract to save bytecode size: it takes much less space to store a
    // number (8 to 16 bits) than the individual string characters.
    //
    // The dynamic string creation algorithm that follows could be implemented in Solidity, but assembly allows for a
    // much denser implementation, again saving bytecode size. Given this function unconditionally reverts, this is a
    // safe place to rely on it without worrying about how its usage might affect e.g. memory contents.
    assembly {
        // First, we need to compute the ASCII representation of the error code. We assume that it is in the 0-999
        // range, so we only need to convert three digits. To convert the digits to ASCII, we add 0x30, the value for
        // the '0' character.

        let units := add(mod(errorCode, 10), 0x30)

        errorCode := div(errorCode, 10)
        let tenths := add(mod(errorCode, 10), 0x30)

        errorCode := div(errorCode, 10)
        let hundreds := add(mod(errorCode, 10), 0x30)

        // With the individual characters, we can now construct the full string. The "BAL#" part is a known constant
        // (0x42414c23): we simply shift this by 24 (to provide space for the 3 bytes of the error code), and add the
        // characters to it, each shifted by a multiple of 8.
        // The revert reason is then shifted left by 200 bits (256 minus the length of the string, 7 characters * 8 bits
        // per character = 56) to locate it in the most significant part of the 256 slot (the beginning of a byte
        // array).

        let revertReason := shl(200, add(0x42414c23000000, add(add(units, shl(8, tenths)), shl(16, hundreds))))

        // We can now encode the reason in memory, which can be safely overwritten as we're about to revert. The encoded
        // message will have the following layout:
        // [ revert reason identifier ] [ string location offset ] [ string length ] [ string contents ]

        // The Solidity revert reason identifier is 0x08c739a0, the function selector of the Error(string) function. We
        // also write zeroes to the next 28 bytes of memory, but those are about to be overwritten.
        mstore(0x0, 0x08c379a000000000000000000000000000000000000000000000000000000000)
        // Next is the offset to the location of the string, which will be placed immediately after (20 bytes away).
        mstore(0x04, 0x0000000000000000000000000000000000000000000000000000000000000020)
        // The string length is fixed: 7 characters.
        mstore(0x24, 7)
        // Finally, the string itself is stored.
        mstore(0x44, revertReason)

        // Even if the string is only 7 bytes long, we need to return a full 32 byte slot containing it. The length of
        // the encoded message is therefore 4 + 32 + 32 + 32 = 100.
        revert(0, 100)
    }
}

library Errors {
    // Math
    uint256 internal constant ADD_OVERFLOW = 0;
    uint256 internal constant SUB_OVERFLOW = 1;
    uint256 internal constant SUB_UNDERFLOW = 2;
    uint256 internal constant MUL_OVERFLOW = 3;
    uint256 internal constant ZERO_DIVISION = 4;
    uint256 internal constant DIV_INTERNAL = 5;
    uint256 internal constant X_OUT_OF_BOUNDS = 6;
    uint256 internal constant Y_OUT_OF_BOUNDS = 7;
    uint256 internal constant PRODUCT_OUT_OF_BOUNDS = 8;
    uint256 internal constant INVALID_EXPONENT = 9;

    // Input
    uint256 internal constant OUT_OF_BOUNDS = 100;
    uint256 internal constant UNSORTED_ARRAY = 101;
    uint256 internal constant UNSORTED_TOKENS = 102;
    uint256 internal constant INPUT_LENGTH_MISMATCH = 103;
    uint256 internal constant ZERO_TOKEN = 104;

    // Shared pools
    uint256 internal constant MIN_TOKENS = 200;
    uint256 internal constant MAX_TOKENS = 201;
    uint256 internal constant MAX_SWAP_FEE_PERCENTAGE = 202;
    uint256 internal constant MIN_SWAP_FEE_PERCENTAGE = 203;
    uint256 internal constant MINIMUM_BPT = 204;
    uint256 internal constant CALLER_NOT_VAULT = 205;
    uint256 internal constant UNINITIALIZED = 206;
    uint256 internal constant BPT_IN_MAX_AMOUNT = 207;
    uint256 internal constant BPT_OUT_MIN_AMOUNT = 208;
    uint256 internal constant EXPIRED_PERMIT = 209;
    uint256 internal constant NOT_TWO_TOKENS = 210;
    uint256 internal constant DISABLED = 211;

    // Pools
    uint256 internal constant MIN_AMP = 300;
    uint256 internal constant MAX_AMP = 301;
    uint256 internal constant MIN_WEIGHT = 302;
    uint256 internal constant MAX_STABLE_TOKENS = 303;
    uint256 internal constant MAX_IN_RATIO = 304;
    uint256 internal constant MAX_OUT_RATIO = 305;
    uint256 internal constant MIN_BPT_IN_FOR_TOKEN_OUT = 306;
    uint256 internal constant MAX_OUT_BPT_FOR_TOKEN_IN = 307;
    uint256 internal constant NORMALIZED_WEIGHT_INVARIANT = 308;
    uint256 internal constant INVALID_TOKEN = 309;
    uint256 internal constant UNHANDLED_JOIN_KIND = 310;
    uint256 internal constant ZERO_INVARIANT = 311;
    uint256 internal constant ORACLE_INVALID_SECONDS_QUERY = 312;
    uint256 internal constant ORACLE_NOT_INITIALIZED = 313;
    uint256 internal constant ORACLE_QUERY_TOO_OLD = 314;
    uint256 internal constant ORACLE_INVALID_INDEX = 315;
    uint256 internal constant ORACLE_BAD_SECS = 316;
    uint256 internal constant AMP_END_TIME_TOO_CLOSE = 317;
    uint256 internal constant AMP_ONGOING_UPDATE = 318;
    uint256 internal constant AMP_RATE_TOO_HIGH = 319;
    uint256 internal constant AMP_NO_ONGOING_UPDATE = 320;
    uint256 internal constant STABLE_INVARIANT_DIDNT_CONVERGE = 321;
    uint256 internal constant STABLE_GET_BALANCE_DIDNT_CONVERGE = 322;
    uint256 internal constant RELAYER_NOT_CONTRACT = 323;
    uint256 internal constant BASE_POOL_RELAYER_NOT_CALLED = 324;
    uint256 internal constant REBALANCING_RELAYER_REENTERED = 325;
    uint256 internal constant GRADUAL_UPDATE_TIME_TRAVEL = 326;
    uint256 internal constant SWAPS_DISABLED = 327;
    uint256 internal constant CALLER_IS_NOT_LBP_OWNER = 328;
    uint256 internal constant PRICE_RATE_OVERFLOW = 329;
    uint256 internal constant INVALID_JOIN_EXIT_KIND_WHILE_SWAPS_DISABLED = 330;
    uint256 internal constant WEIGHT_CHANGE_TOO_FAST = 331;
    uint256 internal constant LOWER_GREATER_THAN_UPPER_TARGET = 332;
    uint256 internal constant UPPER_TARGET_TOO_HIGH = 333;
    uint256 internal constant UNHANDLED_BY_LINEAR_POOL = 334;
    uint256 internal constant OUT_OF_TARGET_RANGE = 335;
    uint256 internal constant UNHANDLED_EXIT_KIND = 336;
    uint256 internal constant UNAUTHORIZED_EXIT = 337;
    uint256 internal constant MAX_MANAGEMENT_SWAP_FEE_PERCENTAGE = 338;
    uint256 internal constant UNHANDLED_BY_MANAGED_POOL = 339;
    uint256 internal constant UNHANDLED_BY_PHANTOM_POOL = 340;
    uint256 internal constant TOKEN_DOES_NOT_HAVE_RATE_PROVIDER = 341;
    uint256 internal constant INVALID_INITIALIZATION = 342;
    uint256 internal constant OUT_OF_NEW_TARGET_RANGE = 343;
    uint256 internal constant FEATURE_DISABLED = 344;
    uint256 internal constant UNINITIALIZED_POOL_CONTROLLER = 345;
    uint256 internal constant SET_SWAP_FEE_DURING_FEE_CHANGE = 346;
    uint256 internal constant SET_SWAP_FEE_PENDING_FEE_CHANGE = 347;
    uint256 internal constant CHANGE_TOKENS_DURING_WEIGHT_CHANGE = 348;
    uint256 internal constant CHANGE_TOKENS_PENDING_WEIGHT_CHANGE = 349;
    uint256 internal constant MAX_WEIGHT = 350;
    uint256 internal constant UNAUTHORIZED_JOIN = 351;
    uint256 internal constant MAX_MANAGEMENT_AUM_FEE_PERCENTAGE = 352;

    // Lib
    uint256 internal constant REENTRANCY = 400;
    uint256 internal constant SENDER_NOT_ALLOWED = 401;
    uint256 internal constant PAUSED = 402;
    uint256 internal constant PAUSE_WINDOW_EXPIRED = 403;
    uint256 internal constant MAX_PAUSE_WINDOW_DURATION = 404;
    uint256 internal constant MAX_BUFFER_PERIOD_DURATION = 405;
    uint256 internal constant INSUFFICIENT_BALANCE = 406;
    uint256 internal constant INSUFFICIENT_ALLOWANCE = 407;
    uint256 internal constant ERC20_TRANSFER_FROM_ZERO_ADDRESS = 408;
    uint256 internal constant ERC20_TRANSFER_TO_ZERO_ADDRESS = 409;
    uint256 internal constant ERC20_MINT_TO_ZERO_ADDRESS = 410;
    uint256 internal constant ERC20_BURN_FROM_ZERO_ADDRESS = 411;
    uint256 internal constant ERC20_APPROVE_FROM_ZERO_ADDRESS = 412;
    uint256 internal constant ERC20_APPROVE_TO_ZERO_ADDRESS = 413;
    uint256 internal constant ERC20_TRANSFER_EXCEEDS_ALLOWANCE = 414;
    uint256 internal constant ERC20_DECREASED_ALLOWANCE_BELOW_ZERO = 415;
    uint256 internal constant ERC20_TRANSFER_EXCEEDS_BALANCE = 416;
    uint256 internal constant ERC20_BURN_EXCEEDS_ALLOWANCE = 417;
    uint256 internal constant SAFE_ERC20_CALL_FAILED = 418;
    uint256 internal constant ADDRESS_INSUFFICIENT_BALANCE = 419;
    uint256 internal constant ADDRESS_CANNOT_SEND_VALUE = 420;
    uint256 internal constant SAFE_CAST_VALUE_CANT_FIT_INT256 = 421;
    uint256 internal constant GRANT_SENDER_NOT_ADMIN = 422;
    uint256 internal constant REVOKE_SENDER_NOT_ADMIN = 423;
    uint256 internal constant RENOUNCE_SENDER_NOT_ALLOWED = 424;
    uint256 internal constant BUFFER_PERIOD_EXPIRED = 425;
    uint256 internal constant CALLER_IS_NOT_OWNER = 426;
    uint256 internal constant NEW_OWNER_IS_ZERO = 427;
    uint256 internal constant CODE_DEPLOYMENT_FAILED = 428;
    uint256 internal constant CALL_TO_NON_CONTRACT = 429;
    uint256 internal constant LOW_LEVEL_CALL_FAILED = 430;
    uint256 internal constant NOT_PAUSED = 431;
    uint256 internal constant ADDRESS_ALREADY_ALLOWLISTED = 432;
    uint256 internal constant ADDRESS_NOT_ALLOWLISTED = 433;
    uint256 internal constant ERC20_BURN_EXCEEDS_BALANCE = 434;
    uint256 internal constant INVALID_OPERATION = 435;
    uint256 internal constant CODEC_OVERFLOW = 436;
    uint256 internal constant IN_RECOVERY_MODE = 437;
    uint256 internal constant NOT_IN_RECOVERY_MODE = 438;
    uint256 internal constant INDUCED_FAILURE = 439;
    uint256 internal constant EXPIRED_SIGNATURE = 440;
    uint256 internal constant MALFORMED_SIGNATURE = 441;
    uint256 internal constant SAFE_CAST_VALUE_CANT_FIT_UINT64 = 442;
    uint256 internal constant UNHANDLED_FEE_TYPE = 443;

    // Vault
    uint256 internal constant INVALID_POOL_ID = 500;
    uint256 internal constant CALLER_NOT_POOL = 501;
    uint256 internal constant SENDER_NOT_ASSET_MANAGER = 502;
    uint256 internal constant USER_DOESNT_ALLOW_RELAYER = 503;
    uint256 internal constant INVALID_SIGNATURE = 504;
    uint256 internal constant EXIT_BELOW_MIN = 505;
    uint256 internal constant JOIN_ABOVE_MAX = 506;
    uint256 internal constant SWAP_LIMIT = 507;
    uint256 internal constant SWAP_DEADLINE = 508;
    uint256 internal constant CANNOT_SWAP_SAME_TOKEN = 509;
    uint256 internal constant UNKNOWN_AMOUNT_IN_FIRST_SWAP = 510;
    uint256 internal constant MALCONSTRUCTED_MULTIHOP_SWAP = 511;
    uint256 internal constant INTERNAL_BALANCE_OVERFLOW = 512;
    uint256 internal constant INSUFFICIENT_INTERNAL_BALANCE = 513;
    uint256 internal constant INVALID_ETH_INTERNAL_BALANCE = 514;
    uint256 internal constant INVALID_POST_LOAN_BALANCE = 515;
    uint256 internal constant INSUFFICIENT_ETH = 516;
    uint256 internal constant UNALLOCATED_ETH = 517;
    uint256 internal constant ETH_TRANSFER = 518;
    uint256 internal constant CANNOT_USE_ETH_SENTINEL = 519;
    uint256 internal constant TOKENS_MISMATCH = 520;
    uint256 internal constant TOKEN_NOT_REGISTERED = 521;
    uint256 internal constant TOKEN_ALREADY_REGISTERED = 522;
    uint256 internal constant TOKENS_ALREADY_SET = 523;
    uint256 internal constant TOKENS_LENGTH_MUST_BE_2 = 524;
    uint256 internal constant NONZERO_TOKEN_BALANCE = 525;
    uint256 internal constant BALANCE_TOTAL_OVERFLOW = 526;
    uint256 internal constant POOL_NO_TOKENS = 527;
    uint256 internal constant INSUFFICIENT_FLASH_LOAN_BALANCE = 528;

    // Fees
    uint256 internal constant SWAP_FEE_PERCENTAGE_TOO_HIGH = 600;
    uint256 internal constant FLASH_LOAN_FEE_PERCENTAGE_TOO_HIGH = 601;
    uint256 internal constant INSUFFICIENT_FLASH_LOAN_FEE_AMOUNT = 602;
    uint256 internal constant AUM_FEE_PERCENTAGE_TOO_HIGH = 603;

    // Misc
    uint256 internal constant SHOULD_NOT_HAPPEN = 999;
}

// File: @balancer-labs/v2-vault/contracts/authorizer/TimelockExecutor.sol



// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

pragma solidity ^0.7.0;

import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/Address.sol";
import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/ReentrancyGuard.sol";

import "./TimelockAuthorizer.sol";

contract TimelockExecutor is ReentrancyGuard {
    TimelockAuthorizer public immutable authorizer;

    constructor() {
        authorizer = TimelockAuthorizer(msg.sender);
    }

    function execute(address target, bytes memory data) external nonReentrant returns (bytes memory result) {
        require(msg.sender == address(authorizer), "ERR_SENDER_NOT_AUTHORIZER");
        return Address.functionCall(target, data);
    }
}

// File: @balancer-labs/v2-solidity-utils/contracts/openzeppelin/Address.sol



// SPDX-License-Identifier: MIT

// Based on the Address library from OpenZeppelin Contracts, altered by removing the `isContract` checks on
// `functionCall` and `functionDelegateCall` in order to save gas, as the recipients are known to be contracts.

pragma solidity ^0.7.0;

import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";

/**
 * @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;
    }

    // solhint-disable max-line-length

    /**
     * @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, Errors.ADDRESS_INSUFFICIENT_BALANCE);

        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
        (bool success, ) = recipient.call{ value: amount }("");
        _require(success, Errors.ADDRESS_CANNOT_SEND_VALUE);
    }

    /**
     * @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:
     *
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.call(data);
        return verifyCallResult(success, returndata);
    }

    // solhint-enable max-line-length

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but passing some native ETH as msg.value to the call.
     *
     * _Available since v3.4._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value
    ) internal returns (bytes memory) {
        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.call{ value: value }(data);
        return verifyCallResult(success, returndata);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return verifyCallResult(success, returndata);
    }

    /**
     * @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling up the
     * revert reason or using the one provided.
     *
     * _Available since v4.3._
     */
    function verifyCallResult(bool success, bytes memory returndata) internal 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(Errors.LOW_LEVEL_CALL_FAILED);
            }
        }
    }
}

// File: @balancer-labs/v2-vault/contracts/authorizer/TimelockAuthorizer.sol



// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

pragma solidity ^0.7.0;
pragma experimental ABIEncoderV2;

import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/IAuthentication.sol";
import "@balancer-labs/v2-interfaces/contracts/vault/IVault.sol";
import "@balancer-labs/v2-interfaces/contracts/vault/IAuthorizer.sol";

import "@balancer-labs/v2-solidity-utils/contracts/helpers/InputHelpers.sol";
import "@balancer-labs/v2-solidity-utils/contracts/math/Math.sol";
import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/Address.sol";
import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/ReentrancyGuard.sol";
import "./TimelockExecutor.sol";

/**
 * @title Timelock Authorizer
 * @author Balancer Labs
 * @dev Authorizer with timelocks (delays).
 *
 * Users are allowed to perform actions if they have the permission to do so.
 *
 * This Authorizer implementation allows defining a delay per action identifier. If a delay is set for an action, users
 * are instead allowed to schedule an execution that will be run in the future by the Authorizer instead of executing it
 * directly themselves.
 *
 * Glossary:
 * - Action: Operation that can be performed to a target contract. These are identified by a unique bytes32 `actionId`
 *   defined by each target contract following `IAuthentication.getActionId`.
 * - Scheduled execution: The Authorizer can define different delays per `actionId` in order to determine that a
 *   specific time window must pass before these can be executed. When a delay is set for an `actionId`, executions
 *   must be scheduled. These executions are identified with an unsigned integer called `scheduledExecutionId`.
 * - Permission: Unique identifier to refer to a user (who) that is allowed to perform an action (what) in a specific
 *   target contract (where). This identifier is called `permissionId` and is computed as
 *   `keccak256(actionId, account, where)`.
 *
 * Permission granularity:
 *   In addition to the who/what/where of a permission, an extra notion of a "specifier" is introduced to enable more
 *   granular configuration. This concept is used within the Authorizer to provide clarity among four ambiguous actions:
 *   granting/revoking permissions, executing scheduled actions, and setting action delays. For example, in managing
 *   the permission to set action delays, it is desirable to delineate whether an account can set delays for all
 *   actions indiscriminately or only for a specific action ID. In this case, the permission's "baseActionId" is the
 *   action ID for scheduling a delay change, and the "specifier" is the action ID for which the delay will be changed.
 *   The "baseActionId" and "specifier" of a permission are combined into a single "extended" `actionId`
 *   by calling `getExtendedActionId(baseActionId, specifier)`.
 *
 * Note that the TimelockAuthorizer doesn't make use of reentrancy guards on the majority of external functions.
 * The only function which makes an external non-view call (and so could initate a reentrancy attack) is `execute`
 * which executes a scheduled execution and so this is the only protected function.
 * In fact a number of the TimelockAuthorizer's functions may only be called through a scheduled execution so reentrancy
 * is necessary in order to be able to call these.
 */
contract TimelockAuthorizer is IAuthorizer, IAuthentication, ReentrancyGuard {
    using Address for address;

    /**
     * @notice An action specifier which grants a general permission to perform all variants of the base action.
     */
    bytes32
        public constant GENERAL_PERMISSION_SPECIFIER = 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff;
    // solhint-disable-previous-line max-line-length

    /**
     * @notice A sentinel value for `where` that will match any address.
     */
    address public constant EVERYWHERE = address(-1);

    // We institute a maximum delay to ensure that actions cannot be accidentally/maliciously disabled through setting
    // an arbitrarily long delay.
    uint256 public constant MAX_DELAY = 2 * (365 days);
    // We need a minimum delay period to ensure that scheduled actions may be properly scrutinised.
    uint256 public constant MIN_DELAY = 5 days;

    struct ScheduledExecution {
        address where;
        bytes data;
        bool executed;
        bool cancelled;
        bool protected;
        uint256 executableAt;
    }

    // solhint-disable var-name-mixedcase
    bytes32 public immutable GRANT_ACTION_ID;
    bytes32 public immutable REVOKE_ACTION_ID;
    bytes32 public immutable EXECUTE_ACTION_ID;
    bytes32 public immutable SCHEDULE_DELAY_ACTION_ID;

    // These action ids do not need to be used by external actors as the action ids above do.
    // Instead they're saved just for gas savings so we can keep them private.
    bytes32 private immutable _GENERAL_GRANT_ACTION_ID;
    bytes32 private immutable _GENERAL_REVOKE_ACTION_ID;

    TimelockExecutor private immutable _executor;
    IAuthentication private immutable _vault;
    uint256 private immutable _rootTransferDelay;

    address private _root;
    address private _pendingRoot;
    ScheduledExecution[] private _scheduledExecutions;
    mapping(bytes32 => bool) private _isPermissionGranted;
    mapping(bytes32 => uint256) private _delaysPerActionId;

    /**
     * @notice Emitted when a new execution `scheduledExecutionId` is scheduled.
     */
    event ExecutionScheduled(bytes32 indexed actionId, uint256 indexed scheduledExecutionId);

    /**
     * @notice Emitted when an execution `scheduledExecutionId` is executed.
     */
    event ExecutionExecuted(uint256 indexed scheduledExecutionId);

    /**
     * @notice Emitted when an execution `scheduledExecutionId` is cancelled.
     */
    event ExecutionCancelled(uint256 indexed scheduledExecutionId);

    /**
     * @notice Emitted when a new `delay` is set in order to perform action `actionId`.
     */
    event ActionDelaySet(bytes32 indexed actionId, uint256 delay);

    /**
     * @notice Emitted when `account` is granted permission to perform action `actionId` in target `where`.
     */
    event PermissionGranted(bytes32 indexed actionId, address indexed account, address indexed where);

    /**
     * @notice Emitted when `account`'s permission to perform action `actionId` in target `where` is revoked.
     */
    event PermissionRevoked(bytes32 indexed actionId, address indexed account, address indexed where);

    /**
     * @notice Emitted when a new `root` is set.
     */
    event RootSet(address indexed root);

    /**
     * @notice Emitted when a new `pendingRoot` is set. The new account must claim ownership for it to take effect.
     */
    event PendingRootSet(address indexed pendingRoot);

    modifier onlyExecutor() {
        _require(msg.sender == address(_executor), Errors.SENDER_NOT_ALLOWED);
        _;
    }

    constructor(
        address admin,
        IAuthentication vault,
        uint256 rootTransferDelay
    ) {
        _setRoot(admin);
        _vault = vault;
        _executor = new TimelockExecutor();
        _rootTransferDelay = rootTransferDelay;

        bytes32 grantActionId = getActionId(TimelockAuthorizer.grantPermissions.selector);
        bytes32 revokeActionId = getActionId(TimelockAuthorizer.revokePermissions.selector);
        bytes32 generalGrantActionId = getExtendedActionId(grantActionId, GENERAL_PERMISSION_SPECIFIER);
        bytes32 generalRevokeActionId = getExtendedActionId(revokeActionId, GENERAL_PERMISSION_SPECIFIER);

        // These don't technically need to be granted as `admin` will be the new root, and can grant these permissions
        // directly to themselves. By granting here improves ergonomics, especially in testing, as the admin is now
        // ready to grant any permission.
        _grantPermission(generalGrantActionId, admin, EVERYWHERE);
        _grantPermission(generalRevokeActionId, admin, EVERYWHERE);

        GRANT_ACTION_ID = grantActionId;
        REVOKE_ACTION_ID = revokeActionId;
        EXECUTE_ACTION_ID = getActionId(TimelockAuthorizer.execute.selector);
        SCHEDULE_DELAY_ACTION_ID = getActionId(TimelockAuthorizer.scheduleDelayChange.selector);
        _GENERAL_GRANT_ACTION_ID = generalGrantActionId;
        _GENERAL_REVOKE_ACTION_ID = generalRevokeActionId;
    }

    /**
     * @notice Returns true if `account` is the root.
     */
    function isRoot(address account) public view returns (bool) {
        return account == _root;
    }

    /**
     * @notice Returns true if `account` is the pending root.
     */
    function isPendingRoot(address account) public view returns (bool) {
        return account == _pendingRoot;
    }

    /**
     * @notice Returns the delay required to transfer the root address.
     */
    function getRootTransferDelay() public view returns (uint256) {
        return _rootTransferDelay;
    }

    /**
     * @notice Returns the vault address.
     */
    function getVault() external view returns (address) {
        return address(_vault);
    }

    /**
     * @notice Returns the executor address.
     */
    function getExecutor() external view returns (address) {
        return address(_executor);
    }

    /**
     * @notice Returns the root address.
     */
    function getRoot() external view returns (address) {
        return _root;
    }

    /**
     * @notice Returns the currently pending new root address.
     */
    function getPendingRoot() external view returns (address) {
        return _pendingRoot;
    }

    /**
     * @notice Returns the action ID for function selector `selector`.
     */
    function getActionId(bytes4 selector) public view override returns (bytes32) {
        return keccak256(abi.encodePacked(bytes32(uint256(address(this))), selector));
    }

    /**
     * @notice Returns the action ID for granting a permission for action `actionId`.
     */
    function getGrantPermissionActionId(bytes32 actionId) public view returns (bytes32) {
        return getExtendedActionId(GRANT_ACTION_ID, actionId);
    }

    /**
     * @notice Returns the action ID for revoking a permission for action `actionId`.
     */
    function getRevokePermissionActionId(bytes32 actionId) public view returns (bytes32) {
        return getExtendedActionId(REVOKE_ACTION_ID, actionId);
    }

    /**
     * @notice Returns the action ID for executing the scheduled action with execution ID `executionId`.
     */
    function getExecuteExecutionActionId(uint256 executionId) public view returns (bytes32) {
        return getExtendedActionId(EXECUTE_ACTION_ID, bytes32(executionId));
    }

    /**
     * @notice Returns the action ID for scheduling setting a new delay for action `actionId`.
     */
    function getScheduleDelayActionId(bytes32 actionId) public view returns (bytes32) {
        return getExtendedActionId(SCHEDULE_DELAY_ACTION_ID, actionId);
    }

    /**
     * @notice Returns the extended action ID for base action ID `baseActionId` with specific params `specifier`.
     */
    function getExtendedActionId(bytes32 baseActionId, bytes32 specifier) public pure returns (bytes32) {
        return keccak256(abi.encodePacked(baseActionId, specifier));
    }

    /**
     * @notice Returns the execution delay for action `actionId`.
     */
    function getActionIdDelay(bytes32 actionId) external view returns (uint256) {
        return _delaysPerActionId[actionId];
    }

    /**
     * @notice Returns the permission ID for action `actionId`, account `account` and target `where`.
     */
    function getPermissionId(
        bytes32 actionId,
        address account,
        address where
    ) public pure returns (bytes32) {
        return keccak256(abi.encodePacked(actionId, account, where));
    }

    /**
     * @notice Returns true if `account` has the permission defined by action `actionId` and target `where`.
     * @dev This function is specific for the strict permission defined by the tuple `(actionId, where)`: `account` may
     * instead hold the global permission for the action `actionId`, also granting them permission on `where`, but this
     * function would return false regardless.
     *
     * For this reason, it's recommended to use `hasPermission` if checking whether `account` is allowed to perform
     * a given action.
     */
    function isPermissionGrantedOnTarget(
        bytes32 actionId,
        address account,
        address where
    ) external view returns (bool) {
        return _isPermissionGranted[getPermissionId(actionId, account, where)];
    }

    /**
     * @notice Returns true if `account` has permission over the action `actionId` in target `where`.
     */
    function hasPermission(
        bytes32 actionId,
        address account,
        address where
    ) public view returns (bool) {
        return
            _isPermissionGranted[getPermissionId(actionId, account, where)] ||
            _isPermissionGranted[getPermissionId(actionId, account, EVERYWHERE)];
    }

    /**
     * @notice Returns true if `account` is allowed to grant permissions for action `actionId` in target `where`.
     */
    function isGranter(
        bytes32 actionId,
        address account,
        address where
    ) public view returns (bool) {
        return _hasPermissionSpecificallyOrGenerally(GRANT_ACTION_ID, account, where, actionId);
    }

    /**
     * @notice Returns true if `account` is allowed to revoke permissions for action `actionId` in target `where`.
     */
    function isRevoker(
        bytes32 actionId,
        address account,
        address where
    ) public view returns (bool) {
        return _hasPermissionSpecificallyOrGenerally(REVOKE_ACTION_ID, account, where, actionId);
    }

    /**
     * @notice Returns true if `account` can perform action `actionId` in target `where`.
     */
    function canPerform(
        bytes32 actionId,
        address account,
        address where
    ) public view override returns (bool) {
        return
            _delaysPerActionId[actionId] > 0 ? account == address(_executor) : hasPermission(actionId, account, where);
    }

    /**
     * @notice Returns true if `account` can grant permissions for action `actionId` in target `where`.
     */
    function canGrant(
        bytes32 actionId,
        address account,
        address where
    ) public view returns (bool) {
        return _canPerformSpecificallyOrGenerally(GRANT_ACTION_ID, account, where, actionId);
    }

    /**
     * @notice Returns true if `account` can revoke permissions for action `actionId` in target `where`.
     */
    function canRevoke(
        bytes32 actionId,
        address account,
        address where
    ) public view returns (bool) {
        return _canPerformSpecificallyOrGenerally(REVOKE_ACTION_ID, account, where, actionId);
    }

    /**
     * @notice Returns the scheduled execution `scheduledExecutionId`.
     */
    function getScheduledExecution(uint256 scheduledExecutionId) external view returns (ScheduledExecution memory) {
        return _scheduledExecutions[scheduledExecutionId];
    }

    /**
     * @notice Returns true if execution `scheduledExecutionId` can be executed.
     * Only true if it is not already executed or cancelled, and if the execution delay has passed.
     */
    function canExecute(uint256 scheduledExecutionId) external view returns (bool) {
        require(scheduledExecutionId < _scheduledExecutions.length, "ACTION_DOES_NOT_EXIST");
        ScheduledExecution storage scheduledExecution = _scheduledExecutions[scheduledExecutionId];
        return
            !scheduledExecution.executed &&
            !scheduledExecution.cancelled &&
            block.timestamp >= scheduledExecution.executableAt;
        // solhint-disable-previous-line not-rely-on-time
    }

    /**
     * @notice Schedules an execution to change the root address to `newRoot`.
     */
    function scheduleRootChange(address newRoot, address[] memory executors)
        external
        returns (uint256 scheduledExecutionId)
    {
        _require(isRoot(msg.sender), Errors.SENDER_NOT_ALLOWED);
        bytes32 actionId = getActionId(this.setPendingRoot.selector);
        bytes memory data = abi.encodeWithSelector(this.setPendingRoot.selector, newRoot);
        return _scheduleWithDelay(actionId, address(this), data, getRootTransferDelay(), executors);
    }

    /**
     * @notice Sets the pending root address to `pendingRoot`.
     * @dev This function can never be called directly - it is only ever called as part of a scheduled execution by
     * the TimelockExecutor after after calling `scheduleRootChange`.
     *
     * Once set as the pending root, `pendingRoot` may then call `claimRoot` to become the new root.
     */
    function setPendingRoot(address pendingRoot) external onlyExecutor {
        _setPendingRoot(pendingRoot);
    }

    /**
     * @notice Transfers root powers from the current to the pending root address.
     * @dev This function prevents accidentally transferring root to an invalid address.
     * To become root, the pending root must call this function to ensure that it's able to interact with this contract.
     */
    function claimRoot() external {
        address currentRoot = _root;
        address pendingRoot = _pendingRoot;
        _require(msg.sender == pendingRoot, Errors.SENDER_NOT_ALLOWED);

        // Grant powers to new root to grant or revoke any permission over any contract.
        _grantPermission(_GENERAL_GRANT_ACTION_ID, pendingRoot, EVERYWHERE);
        _grantPermission(_GENERAL_REVOKE_ACTION_ID, pendingRoot, EVERYWHERE);

        // Revoke these powers from the outgoing root.
        _revokePermission(_GENERAL_GRANT_ACTION_ID, currentRoot, EVERYWHERE);
        _revokePermission(_GENERAL_REVOKE_ACTION_ID, currentRoot, EVERYWHERE);

        // Complete the root transfer and reset the pending root.
        _setRoot(pendingRoot);
        _setPendingRoot(address(0));
    }

    /**
     * @notice Sets a new delay `delay` for action `actionId`.
     * @dev This function can never be called directly - it is only ever called as part of a scheduled execution by
     * the TimelockExecutor after after calling `scheduleDelayChange`.
     */
    function setDelay(bytes32 actionId, uint256 delay) external onlyExecutor {
        bytes32 setAuthorizerActionId = _vault.getActionId(IVault.setAuthorizer.selector);
        bool isAllowed = actionId == setAuthorizerActionId || delay <= _delaysPerActionId[setAuthorizerActionId];
        require(isAllowed, "DELAY_EXCEEDS_SET_AUTHORIZER");

        _delaysPerActionId[actionId] = delay;
        emit ActionDelaySet(actionId, delay);
    }

    /**
     * @notice Schedules an execution to set action `actionId`'s delay to `newDelay`.
     */
    function scheduleDelayChange(
        bytes32 actionId,
        uint256 newDelay,
        address[] memory executors
    ) external returns (uint256 scheduledExecutionId) {
        require(newDelay <= MAX_DELAY, "DELAY_TOO_LARGE");
        _require(isRoot(msg.sender), Errors.SENDER_NOT_ALLOWED);

        // The delay change is scheduled so that it's never possible to execute an action in a shorter time than the
        // current delay.
        //
        // If we're reducing the action's delay then we must first wait for the difference between the two delays.
        // This means that if we immediately schedule the action for execution once the delay is reduced, then
        // these two delays combined will result in the original delay.
        //
        // If we're increasing the delay on an action, we could execute this change immediately as it's impossible to
        // perform an action sooner by increasing its delay. Requiring a potentially long delay before increasing the
        // delay just adds unnecessary friction to increasing security for sensitive actions.
        //
        // We also enforce a minimum delay period to allow proper scrutiny of the change of the action's delay.

        uint256 actionDelay = _delaysPerActionId[actionId];
        uint256 executionDelay = newDelay < actionDelay ? Math.max(actionDelay - newDelay, MIN_DELAY) : MIN_DELAY;

        bytes32 scheduleDelayActionId = getScheduleDelayActionId(actionId);
        bytes memory data = abi.encodeWithSelector(this.setDelay.selector, actionId, newDelay);
        return _scheduleWithDelay(scheduleDelayActionId, address(this), data, executionDelay, executors);
    }

    /**
     * @notice Schedules an arbitrary execution of `data` in target `where`.
     */
    function schedule(
        address where,
        bytes memory data,
        address[] memory executors
    ) external returns (uint256 scheduledExecutionId) {
        // Allowing scheduling arbitrary calls into the TimelockAuthorizer is dangerous.
        //
        // It is expected that only the `root` account can initiate a root transfer as this condition is enforced
        // by the `scheduleRootChange` function which is the expected method of scheduling a call to `setPendingRoot`.
        // If a call to `setPendingRoot` could be scheduled using this function as well as `scheduleRootChange` then
        // accounts other than `root` could initiate a root transfer (provided they had the necessary permission).
        // Similarly, `setDelay` can only be called if scheduled via `scheduleDelayChange`.
        //
        // For this reason we disallow this function from scheduling calls to functions on the Authorizer to ensure that
        // these actions can only be scheduled through specialised functions.
        require(where != address(this), "CANNOT_SCHEDULE_AUTHORIZER_ACTIONS");

        // We also disallow the TimelockExecutor from attempting to call into itself. Otherwise the above protection
        // could be bypassed by wrapping a call to `setPendingRoot` inside of a call causing the TimelockExecutor to
        // reenter itself, essentially hiding the fact that `where == address(this)` inside `data`.
        //
        // Note: The TimelockExecutor only accepts calls from the TimelockAuthorizer (i.e. not from itself) so this
        // scenario should be impossible but this check is cheap so we enforce it here as well anyway.
        require(where != address(_executor), "ATTEMPTING_EXECUTOR_REENTRANCY");

        bytes32 actionId = IAuthentication(where).getActionId(_decodeSelector(data));
        _require(hasPermission(actionId, msg.sender, where), Errors.SENDER_NOT_ALLOWED);
        return _schedule(actionId, where, data, executors);
    }

    /**
     * @notice Executes a scheduled action `scheduledExecutionId`.
     */
    function execute(uint256 scheduledExecutionId) external nonReentrant returns (bytes memory result) {
        require(scheduledExecutionId < _scheduledExecutions.length, "ACTION_DOES_NOT_EXIST");
        ScheduledExecution storage scheduledExecution = _scheduledExecutions[scheduledExecutionId];
        require(!scheduledExecution.executed, "ACTION_ALREADY_EXECUTED");
        require(!scheduledExecution.cancelled, "ACTION_ALREADY_CANCELLED");

        // solhint-disable-next-line not-rely-on-time
        require(block.timestamp >= scheduledExecution.executableAt, "ACTION_NOT_EXECUTABLE");
        if (scheduledExecution.protected) {
            bytes32 executeScheduledActionId = getExecuteExecutionActionId(scheduledExecutionId);
            bool isAllowed = hasPermission(executeScheduledActionId, msg.sender, address(this));
            _require(isAllowed, Errors.SENDER_NOT_ALLOWED);
        }

        scheduledExecution.executed = true;
        // Note that this is the only place in the entire contract we perform a non-view call to an external contract.
        result = _executor.execute(scheduledExecution.where, scheduledExecution.data);
        emit ExecutionExecuted(scheduledExecutionId);
    }

    /**
     * @notice Cancels a scheduled action `scheduledExecutionId`.
     * @dev The permission to cancel a scheduled action is the same one used to schedule it.
     *
     * Note that in the case of cancelling a malicious granting or revocation of permissions to an address,
     * we must assume that the granter/revoker status of all non-malicious addresses will be revoked as calls to
     * manageGranter/manageRevoker have no delays associated with them.
     */
    function cancel(uint256 scheduledExecutionId) external {
        require(scheduledExecutionId < _scheduledExecutions.length, "ACTION_DOES_NOT_EXIST");
        ScheduledExecution storage scheduledExecution = _scheduledExecutions[scheduledExecutionId];

        require(!scheduledExecution.executed, "ACTION_ALREADY_EXECUTED");
        require(!scheduledExecution.cancelled, "ACTION_ALREADY_CANCELLED");

        // The permission to cancel a scheduled action is the same one used to schedule it.
        // The root address may cancel any action even without this permission.
        IAuthentication target = IAuthentication(scheduledExecution.where);
        bytes32 actionId = target.getActionId(_decodeSelector(scheduledExecution.data));
        _require(
            hasPermission(actionId, msg.sender, scheduledExecution.where) || isRoot(msg.sender),
            Errors.SENDER_NOT_ALLOWED
        );

        scheduledExecution.cancelled = true;
        emit ExecutionCancelled(scheduledExecutionId);
    }

    /**
     * @notice Sets `account`'s granter status to `allowed` for action `actionId` in target `where`.
     * @dev Note that granters can revoke the granter status of other granters, even removing the root.
     * However the root can always rejoin, and then remove any malicious granters.
     *
     * Note that there are no delays associated with adding or removing granters. This is based on the assumption that
     * any action which a malicous user could exploit to damage the protocol will have a sufficiently long delay
     * associated with either granting permission for or exercising that permission such that the root will be able to
     * reestablish control and cancel the action before it can be executed.
     */
    function manageGranter(
        bytes32 actionId,
        address account,
        address where,
        bool allowed
    ) external {
        // Root may grant or revoke granter status from any address.
        // Granters may only revoke a granter status from any address.
        bool isAllowed = isRoot(msg.sender) || (!allowed && isGranter(actionId, msg.sender, where));
        _require(isAllowed, Errors.SENDER_NOT_ALLOWED);

        bytes32 grantPermissionsActionId = getGrantPermissionActionId(actionId);
        (allowed ? _grantPermission : _revokePermission)(grantPermissionsActionId, account, where);
    }

    /**
     * @notice Grants multiple permissions to a single `account`.
     * @dev This function can only be used for actions that have no grant delay. For those that do, use
     * `scheduleGrantPermission` instead.
     */
    function grantPermissions(
        bytes32[] memory actionIds,
        address account,
        address[] memory where
    ) external {
        InputHelpers.ensureInputLengthMatch(actionIds.length, where.length);
        for (uint256 i = 0; i < actionIds.length; i++) {
            // For permissions that have a delay when granting, `canGrant` will return false. `scheduleGrantPermission`
            // will succeed as it checks `isGranter` instead.
            // Note that `canGrant` will return true for the executor if the permission has a delay.
            _require(canGrant(actionIds[i], msg.sender, where[i]), Errors.SENDER_NOT_ALLOWED);
            _grantPermission(actionIds[i], account, where[i]);
        }
    }

    /**
     * @notice Schedules a grant permission to `account` for action `actionId` in target `where`.
     */
    function scheduleGrantPermission(
        bytes32 actionId,
        address account,
        address where,
        address[] memory executors
    ) external returns (uint256 scheduledExecutionId) {
        _require(isGranter(actionId, msg.sender, where), Errors.SENDER_NOT_ALLOWED);
        bytes memory data = abi.encodeWithSelector(this.grantPermissions.selector, _ar(actionId), account, _ar(where));
        bytes32 grantPermissionId = getGrantPermissionActionId(actionId);
        return _schedule(grantPermissionId, address(this), data, executors);
    }

    /**
     * @notice Sets `account`'s revoker status to `allowed` for action `actionId` in target `where`.
     * @dev Note that revokers can revoke the revoker status of other revokers, even banning the root.
     * However the root can always rejoin, and then remove any malicious revokers.
     *
     * Note that there are no delays associated with adding or removing revokers. This is based on the assumption that
     * any permissions for which revocation from key addresses would be dangerous (e.g. preventing the BalancerMinter
     * from minting BAL) have sufficiently long delays associated with revoking them that the root will be able to
     * reestablish control and cancel the revocation before the scheduled revocation can be executed.
     */
    function manageRevoker(
        bytes32 actionId,
        address account,
        address where,
        bool allowed
    ) external {
        // Root may grant or revoke revoker status from any address.
        // Revokers may only revoke a revoker status from any address.
        bool isAllowed = isRoot(msg.sender) || (!allowed && isRevoker(actionId, msg.sender, where));
        _require(isAllowed, Errors.SENDER_NOT_ALLOWED);

        bytes32 revokePermissionsActionId = getRevokePermissionActionId(actionId);
        (allowed ? _grantPermission : _revokePermission)(revokePermissionsActionId, account, where);
    }

    /**
     * @notice Revokes multiple permissions from a single `account`.
     * @dev This function can only be used for actions that have no revoke delay. For those that do, use
     * `scheduleRevokePermission` instead.
     */
    function revokePermissions(
        bytes32[] memory actionIds,
        address account,
        address[] memory where
    ) external {
        InputHelpers.ensureInputLengthMatch(actionIds.length, where.length);
        for (uint256 i = 0; i < actionIds.length; i++) {
            // For permissions that have a delay when granting, `canRevoke` will return false.
            // `scheduleRevokePermission` will succeed as it checks `isRevoker` instead.
            // Note that `canRevoke` will return true for the executor if the permission has a delay.
            _require(canRevoke(actionIds[i], msg.sender, where[i]), Errors.SENDER_NOT_ALLOWED);
            _revokePermission(actionIds[i], account, where[i]);
        }
    }

    /**
     * @notice Schedules a revoke permission from `account` for action `actionId` in target `where`.
     */
    function scheduleRevokePermission(
        bytes32 actionId,
        address account,
        address where,
        address[] memory executors
    ) external returns (uint256 scheduledExecutionId) {
        _require(isRevoker(actionId, msg.sender, where), Errors.SENDER_NOT_ALLOWED);
        bytes memory data = abi.encodeWithSelector(this.revokePermissions.selector, _ar(actionId), account, _ar(where));
        bytes32 revokePermissionId = getRevokePermissionActionId(actionId);
        return _schedule(revokePermissionId, address(this), data, executors);
    }

    /**
     * @notice Revokes multiple permissions from the caller.
     * @dev Note that the caller can always renounce permissions, even if revoking them would typically be
     * subject to a delay.
     */
    function renouncePermissions(bytes32[] memory actionIds, address[] memory where) external {
        InputHelpers.ensureInputLengthMatch(actionIds.length, where.length);
        for (uint256 i = 0; i < actionIds.length; i++) {
            _revokePermission(actionIds[i], msg.sender, where[i]);
        }
    }

    function _grantPermission(
        bytes32 actionId,
        address account,
        address where
    ) private {
        bytes32 permission = getPermissionId(actionId, account, where);
        if (!_isPermissionGranted[permission]) {
            _isPermissionGranted[permission] = true;
            emit PermissionGranted(actionId, account, where);
        }
    }

    function _revokePermission(
        bytes32 actionId,
        address account,
        address where
    ) private {
        bytes32 permission = getPermissionId(actionId, account, where);
        if (_isPermissionGranted[permission]) {
            _isPermissionGranted[permission] = false;
            emit PermissionRevoked(actionId, account, where);
        }
    }

    function _schedule(
        bytes32 actionId,
        address where,
        bytes memory data,
        address[] memory executors
    ) private returns (uint256 scheduledExecutionId) {
        uint256 delay = _delaysPerActionId[actionId];
        require(delay > 0, "CANNOT_SCHEDULE_ACTION");
        return _scheduleWithDelay(actionId, where, data, delay, executors);
    }

    function _scheduleWithDelay(
        bytes32 actionId,
        address where,
        bytes memory data,
        uint256 delay,
        address[] memory executors
    ) private returns (uint256 scheduledExecutionId) {
        scheduledExecutionId = _scheduledExecutions.length;
        emit ExecutionScheduled(actionId, scheduledExecutionId);

        // solhint-disable-next-line not-rely-on-time
        uint256 executableAt = block.timestamp + delay;
        bool protected = executors.length > 0;

        _scheduledExecutions.push(
            ScheduledExecution({
                where: where,
                data: data,
                executed: false,
                cancelled: false,
                protected: protected,
                executableAt: executableAt
            })
        );

        bytes32 executeActionId = getExecuteExecutionActionId(scheduledExecutionId);
        for (uint256 i = 0; i < executors.length; i++) {
            _grantPermission(executeActionId, executors[i], address(this));
        }
    }

    /**
     * @notice Returns if `account` has permission to perform the action `(baseActionId, specifier)` on target `where`.
     * @dev This function differs from `_canPerformSpecificallyOrGenerally` as it *doesn't* take into account whether
     * there is a delay for the action associated with the permission being checked.
     *
     * The address `account` may have the permission associated with the provided action but that doesn't necessarily
     * mean that it may perform that action. If there is no delay associated with this action, `account` may perform the
     * action directly. If there is a delay, then `account` is instead able to schedule that action to be performed
     * at a later date.
     *
     * This function returns true in both cases.
     */
    function _hasPermissionSpecificallyOrGenerally(
        bytes32 baseActionId,
        address account,
        address where,
        bytes32 specifier
    ) internal view returns (bool) {
        bytes32 specificActionId = getExtendedActionId(baseActionId, specifier);
        bytes32 generalActionId = getExtendedActionId(baseActionId, GENERAL_PERMISSION_SPECIFIER);
        return hasPermission(specificActionId, account, where) || hasPermission(generalActionId, account, where);
    }

    /**
     * @notice Returns if `account` can perform the action `(baseActionId, specifier)` on target `where`.
     * @dev This function differs from `_hasPermissionSpecificallyOrGenerally` as it *does* take into account whether
     * there is a delay for the action associated with the permission being checked.
     *
     * The address `account` may have the permission associated with the provided action but that doesn't necessarily
     * mean that it may perform that action. If there is no delay associated with this action, `account` may perform the
     * action directly. If there is a delay, then `account` is instead able to schedule that action to be performed
     * at a later date.
     *
     * This function only returns true only in the first case (except for actions performed by the authorizer timelock).
     */
    function _canPerformSpecificallyOrGenerally(
        bytes32 baseActionId,
        address account,
        address where,
        bytes32 specifier
    ) internal view returns (bool) {
        // If there is a delay defined for the specific action ID, then the sender must be the authorizer (scheduled
        // execution)
        bytes32 specificActionId = getExtendedActionId(baseActionId, specifier);
        if (_delaysPerActionId[specificActionId] > 0) {
            return account == address(_executor);
        }

        // If there is no delay, we check if the account has that permission
        if (hasPermission(specificActionId, account, where)) {
            return true;
        }

        // If the account doesn't have the explicit permission, we repeat for the general permission
        bytes32 generalActionId = getExtendedActionId(baseActionId, GENERAL_PERMISSION_SPECIFIER);
        return canPerform(generalActionId, account, where);
    }

    /**
     * @dev Sets the root address to `root`.
     */
    function _setRoot(address root) internal {
        _root = root;
        emit RootSet(root);
    }

    /**
     * @dev Sets the pending root address to `pendingRoot`.
     */
    function _setPendingRoot(address pendingRoot) internal {
        _pendingRoot = pendingRoot;
        emit PendingRootSet(pendingRoot);
    }

    function _decodeSelector(bytes memory data) internal pure returns (bytes4) {
        // The bytes4 type is left-aligned and padded with zeros: we make use of that property to build the selector
        if (data.length < 4) return bytes4(0);
        return bytes4(data[0]) | (bytes4(data[1]) >> 8) | (bytes4(data[2]) >> 16) | (bytes4(data[3]) >> 24);
    }

    function _ar(bytes32 item) private pure returns (bytes32[] memory result) {
        result = new bytes32[](1);
        result[0] = item;
    }

    function _ar(address item) private pure returns (address[] memory result) {
        result = new address[](1);
        result[0] = item;
    }
}

// File: @balancer-labs/v2-solidity-utils/contracts/helpers/InputHelpers.sol



// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

pragma solidity ^0.7.0;

import "@balancer-labs/v2-interfaces/contracts/solidity-utils/openzeppelin/IERC20.sol";
import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";

library InputHelpers {
    function ensureInputLengthMatch(uint256 a, uint256 b) internal pure {
        _require(a == b, Errors.INPUT_LENGTH_MISMATCH);
    }

    function ensureInputLengthMatch(
        uint256 a,
        uint256 b,
        uint256 c
    ) internal pure {
        _require(a == b && b == c, Errors.INPUT_LENGTH_MISMATCH);
    }

    function ensureArrayIsSorted(IERC20[] memory array) internal pure {
        address[] memory addressArray;
        // solhint-disable-next-line no-inline-assembly
        assembly {
            addressArray := array
        }
        ensureArrayIsSorted(addressArray);
    }

    function ensureArrayIsSorted(address[] memory array) internal pure {
        if (array.length < 2) {
            return;
        }

        address previous = array[0];
        for (uint256 i = 1; i < array.length; ++i) {
            address current = array[i];
            _require(previous < current, Errors.UNSORTED_ARRAY);
            previous = current;
        }
    }
}

// File: @balancer-labs/v2-solidity-utils/contracts/math/Math.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.7.0;

import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";

/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow checks.
 * Adapted from OpenZeppelin's SafeMath library.
 */
library Math {
    /**
     * @dev Returns the absolute value of a signed integer.
     */
    function abs(int256 a) internal pure returns (uint256) {
        return a > 0 ? uint256(a) : uint256(-a);
    }

    /**
     * @dev Returns the addition of two unsigned integers of 256 bits, reverting on overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        _require(c >= a, Errors.ADD_OVERFLOW);
        return c;
    }

    /**
     * @dev Returns the addition of two signed integers, reverting on overflow.
     */
    function add(int256 a, int256 b) internal pure returns (int256) {
        int256 c = a + b;
        _require((b >= 0 && c >= a) || (b < 0 && c < a), Errors.ADD_OVERFLOW);
        return c;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers of 256 bits, reverting on overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        _require(b <= a, Errors.SUB_OVERFLOW);
        uint256 c = a - b;
        return c;
    }

    /**
     * @dev Returns the subtraction of two signed integers, reverting on overflow.
     */
    function sub(int256 a, int256 b) internal pure returns (int256) {
        int256 c = a - b;
        _require((b >= 0 && c <= a) || (b < 0 && c > a), Errors.SUB_OVERFLOW);
        return c;
    }

    /**
     * @dev Returns the largest of two numbers of 256 bits.
     */
    function max(uint256 a, uint256 b) internal pure returns (uint256) {
        return a >= b ? a : b;
    }

    /**
     * @dev Returns the smallest of two numbers of 256 bits.
     */
    function min(uint256 a, uint256 b) internal pure returns (uint256) {
        return a < b ? a : b;
    }

    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a * b;
        _require(a == 0 || c / a == b, Errors.MUL_OVERFLOW);
        return c;
    }

    function div(
        uint256 a,
        uint256 b,
        bool roundUp
    ) internal pure returns (uint256) {
        return roundUp ? divUp(a, b) : divDown(a, b);
    }

    function divDown(uint256 a, uint256 b) internal pure returns (uint256) {
        _require(b != 0, Errors.ZERO_DIVISION);
        return a / b;
    }

    function divUp(uint256 a, uint256 b) internal pure returns (uint256) {
        _require(b != 0, Errors.ZERO_DIVISION);

        if (a == 0) {
            return 0;
        } else {
            return 1 + (a - 1) / b;
        }
    }
}

// File: contracts/20220704-timelock-authorizer-migrator/TimelockAuthorizerMigrator.sol



// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

pragma solidity ^0.7.0;
pragma experimental ABIEncoderV2;

import "@balancer-labs/v2-interfaces/contracts/vault/IBasicAuthorizer.sol";
import "@balancer-labs/v2-interfaces/contracts/vault/IVault.sol";

import "@balancer-labs/v2-solidity-utils/contracts/math/Math.sol";

import "@balancer-labs/v2-vault/contracts/authorizer/TimelockAuthorizer.sol";

contract TimelockAuthorizerMigrator {
    bytes32
        public constant GENERAL_PERMISSION_SPECIFIER = 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff;
    // solhint-disable-previous-line max-line-length
    address public constant EVERYWHERE = address(-1);
    uint256 public constant CHANGE_ROOT_DELAY = 4 weeks;
    bytes32 public constant DEFAULT_ADMIN_ROLE = 0x00;

    IVault public immutable vault;
    address public immutable root;
    IBasicAuthorizer public immutable oldAuthorizer;
    TimelockAuthorizer public immutable newAuthorizer;

    uint256 public rootChangeExecutionId;

    struct RoleData {
        address grantee;
        bytes32 role;
        address target;
    }

    struct DelayData {
        bytes32 actionId;
        uint256 newDelay;
    }

    /**
     * @dev Reverts if _rolesData contains a role for an account which doesn't hold the same role on the old Authorizer.
     */
    constructor(
        IVault _vault,
        address _root,
        IBasicAuthorizer _oldAuthorizer,
        RoleData[] memory _rolesData,
        RoleData[] memory _grantersData,
        RoleData[] memory _revokersData,
        DelayData[] memory _executeDelaysData,
        DelayData[] memory _grantDelaysData
    ) {
        // At creation, the migrator will be the root of the TimelockAuthorizer.
        // Once the migration is complete, the root permission will be transferred to `_root`.
        TimelockAuthorizer _newAuthorizer = new TimelockAuthorizer(address(this), _vault, CHANGE_ROOT_DELAY);
        newAuthorizer = _newAuthorizer;
        oldAuthorizer = _oldAuthorizer;
        root = _root;
        vault = _vault;

        for (uint256 i = 0; i < _rolesData.length; i++) {
            RoleData memory roleData = _rolesData[i];
            // We require that any permissions being copied from the old Authorizer must exist on the old Authorizer.
            // This simplifies verification of the permissions being added to the new TimelockAuthorizer.
            require(_oldAuthorizer.canPerform(roleData.role, roleData.grantee, roleData.target), "UNEXPECTED_ROLE");
            _newAuthorizer.grantPermissions(_arr(roleData.role), roleData.grantee, _arr(roleData.target));
        }
        for (uint256 i = 0; i < _grantersData.length; i++) {
            // There's no concept of a "granter" on the old Authorizer so we cannot verify these onchain.
            // We must manually verify that these permissions are set sensibly.
            _newAuthorizer.manageGranter(
                _grantersData[i].role,
                _grantersData[i].grantee,
                _grantersData[i].target,
                true
            );
        }
        for (uint256 i = 0; i < _revokersData.length; i++) {
            // Similarly to granters, we must manually verify that these permissions are set sensibly.
            _newAuthorizer.manageRevoker(
                _revokersData[i].role,
                _revokersData[i].grantee,
                _revokersData[i].target,
                true
            );
        }

        // Setting the initial value for a delay requires us to wait 3 days before we can complete setting it.
        // We schedule them now to ensure that they're ready to execute once `CHANGE_ROOT_DELAY` has passed.
        for (uint256 i = 0; i < _executeDelaysData.length; i++) {
            // We're not wanting to set a delay greater than 1 month initially so fail early if we're doing so.
            require(_executeDelaysData[i].newDelay <= 30 days, "UNEXPECTED_LARGE_DELAY");
            _newAuthorizer.scheduleDelayChange(
                _executeDelaysData[i].actionId,
                _executeDelaysData[i].newDelay,
                _arr(address(this))
            );
        }
        for (uint256 i = 0; i < _grantDelaysData.length; i++) {
            // We're not wanting to set a delay greater than 1 month initially so fail early if we're doing so.
            require(_grantDelaysData[i].newDelay <= 30 days, "UNEXPECTED_LARGE_DELAY");
            _newAuthorizer.scheduleDelayChange(
                _newAuthorizer.getGrantPermissionActionId(_grantDelaysData[i].actionId),
                _grantDelaysData[i].newDelay,
                _arr(address(this))
            );
        }

        // Enqueue a root change execution in the new authorizer to set it to the desired root address.
        // We only allow the migrator to execute this transaction to avoid it being triggered too early.
        rootChangeExecutionId = _newAuthorizer.scheduleRootChange(_root, _arr(address(this)));
    }

    /**
     * @notice Executes the scheduled setup of delays on the new authorizer
     */
    function executeDelays() external {
        require(newAuthorizer.canExecute(0), "CANNOT_TRIGGER_DELAYS_MIGRATION_YET");
        // As execution IDs are sequential, we can just iterate from 0 to the first non-delay (root transfer) execution.
        for (uint256 i = 0; i < rootChangeExecutionId; i++) {
            newAuthorizer.execute(i);
        }
    }

    /**
     * @notice Begins transfer of root powers from the migrator to the specified address.
     * @dev The setup of delays on the new authorizer must be executed before calling this function.
     */
    function startRootTransfer() external {
        // Check that the delays have been set up on the new authorizer.
        // Checking the first delay has been set is sufficient.
        // This check is shortcircuited if there are no delays to set up (`rootChangeExecutionId == 0`).
        require(
            rootChangeExecutionId == 0 || newAuthorizer.getScheduledExecution(0).executed,
            "DELAYS_NOT_MIGRATED_YET"
        );

        // Finally trigger the first step of transferring root ownership over the TimelockAuthorizer to `root`.
        // Before the migration can be finalized, `root` must call `claimRoot` on the `TimelockAuthorizer`.
        require(newAuthorizer.canExecute(rootChangeExecutionId), "CANNOT_TRIGGER_ROOT_CHANGE_YET");
        newAuthorizer.execute(rootChangeExecutionId);
    }

    /**
     * @notice Complete the authorizer migration by updating the Vault to point to the new authorizer.
     * @dev `root` must call `claimRoot` on `newAuthorizer` before we update the Vault to point at it.
     */
    function finalizeMigration() external {
        // Safety check to avoid us migrating to a authorizer with an invalid root.
        // `root` must call `claimRoot` on `newAuthorizer` before we update the Vault to point at it.
        require(newAuthorizer.isRoot(root), "ROOT_NOT_CLAIMED_YET");

        // Ensure the migrator contract has authority to change the vault's authorizer
        bytes32 setAuthorizerId = IAuthentication(address(vault)).getActionId(IVault.setAuthorizer.selector);
        bool canSetAuthorizer = oldAuthorizer.canPerform(setAuthorizerId, address(this), address(vault));
        require(canSetAuthorizer, "MIGRATOR_CANNOT_SET_AUTHORIZER");

        // Finally change the authorizer in the vault.
        vault.setAuthorizer(newAuthorizer);
    }

    // Helper functions

    function _arr(bytes32 a) internal pure returns (bytes32[] memory arr) {
        arr = new bytes32[](1);
        arr[0] = a;
    }

    function _arr(address a) internal pure returns (address[] memory arr) {
        arr = new address[](1);
        arr[0] = a;
    }
}

// File: @balancer-labs/v2-interfaces/contracts/vault/IBasicAuthorizer.sol



// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

pragma solidity ^0.7.0;

import "./IAuthorizer.sol";

interface IBasicAuthorizer is IAuthorizer {
    // solhint-disable-next-line func-name-mixedcase
    function DEFAULT_ADMIN_ROLE() external returns (bytes32);

    function getRoleAdmin(bytes32 role) external view returns (bytes32);

    function getRoleMember(bytes32 role, uint256 index) external view returns (address);

    function getRoleMemberCount(bytes32 role) external view returns (uint256);
}