// SPDX-License-Identifier: AGPL-3.0-only
pragma solidity >=0.8.0;

/// @notice Modern and gas efficient ERC20 + EIP-2612 implementation.
/// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/tokens/ERC20.sol)
/// @author Modified from Uniswap (https://github.com/Uniswap/uniswap-v2-core/blob/master/contracts/UniswapV2ERC20.sol)
/// @dev Do not manually set balances without updating totalSupply, as the sum of all user balances must not exceed it.
abstract contract ERC20 {
    /*//////////////////////////////////////////////////////////////
                                 EVENTS
    //////////////////////////////////////////////////////////////*/

    event Transfer(address indexed from, address indexed to, uint256 amount);

    event Approval(address indexed owner, address indexed spender, uint256 amount);

    /*//////////////////////////////////////////////////////////////
                            METADATA STORAGE
    //////////////////////////////////////////////////////////////*/

    string public name;

    string public symbol;

    uint8 public immutable decimals;

    /*//////////////////////////////////////////////////////////////
                              ERC20 STORAGE
    //////////////////////////////////////////////////////////////*/

    uint256 public totalSupply;

    mapping(address => uint256) public balanceOf;

    mapping(address => mapping(address => uint256)) public allowance;

    /*//////////////////////////////////////////////////////////////
                            EIP-2612 STORAGE
    //////////////////////////////////////////////////////////////*/

    uint256 internal immutable INITIAL_CHAIN_ID;

    bytes32 internal immutable INITIAL_DOMAIN_SEPARATOR;

    mapping(address => uint256) public nonces;

    /*//////////////////////////////////////////////////////////////
                               CONSTRUCTOR
    //////////////////////////////////////////////////////////////*/

    constructor(
        string memory _name,
        string memory _symbol,
        uint8 _decimals
    ) {
        name = _name;
        symbol = _symbol;
        decimals = _decimals;

        INITIAL_CHAIN_ID = block.chainid;
        INITIAL_DOMAIN_SEPARATOR = computeDomainSeparator();
    }

    /*//////////////////////////////////////////////////////////////
                               ERC20 LOGIC
    //////////////////////////////////////////////////////////////*/

    function approve(address spender, uint256 amount) public virtual returns (bool) {
        allowance[msg.sender][spender] = amount;

        emit Approval(msg.sender, spender, amount);

        return true;
    }

    function transfer(address to, uint256 amount) public virtual returns (bool) {
        balanceOf[msg.sender] -= amount;

        // Cannot overflow because the sum of all user
        // balances can't exceed the max uint256 value.
        unchecked {
            balanceOf[to] += amount;
        }

        emit Transfer(msg.sender, to, amount);

        return true;
    }

    function transferFrom(
        address from,
        address to,
        uint256 amount
    ) public virtual returns (bool) {
        uint256 allowed = allowance[from][msg.sender]; // Saves gas for limited approvals.

        if (allowed != type(uint256).max) allowance[from][msg.sender] = allowed - amount;

        balanceOf[from] -= amount;

        // Cannot overflow because the sum of all user
        // balances can't exceed the max uint256 value.
        unchecked {
            balanceOf[to] += amount;
        }

        emit Transfer(from, to, amount);

        return true;
    }

    /*//////////////////////////////////////////////////////////////
                             EIP-2612 LOGIC
    //////////////////////////////////////////////////////////////*/

    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) public virtual {
        require(deadline >= block.timestamp, "PERMIT_DEADLINE_EXPIRED");

        // Unchecked because the only math done is incrementing
        // the owner's nonce which cannot realistically overflow.
        unchecked {
            address recoveredAddress = ecrecover(
                keccak256(
                    abi.encodePacked(
                        "\x19\x01",
                        DOMAIN_SEPARATOR(),
                        keccak256(
                            abi.encode(
                                keccak256(
                                    "Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)"
                                ),
                                owner,
                                spender,
                                value,
                                nonces[owner]++,
                                deadline
                            )
                        )
                    )
                ),
                v,
                r,
                s
            );

            require(recoveredAddress != address(0) && recoveredAddress == owner, "INVALID_SIGNER");

            allowance[recoveredAddress][spender] = value;
        }

        emit Approval(owner, spender, value);
    }

    function DOMAIN_SEPARATOR() public view virtual returns (bytes32) {
        return block.chainid == INITIAL_CHAIN_ID ? INITIAL_DOMAIN_SEPARATOR : computeDomainSeparator();
    }

    function computeDomainSeparator() internal view virtual returns (bytes32) {
        return
            keccak256(
                abi.encode(
                    keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"),
                    keccak256(bytes(name)),
                    keccak256("1"),
                    block.chainid,
                    address(this)
                )
            );
    }

    /*//////////////////////////////////////////////////////////////
                        INTERNAL MINT/BURN LOGIC
    //////////////////////////////////////////////////////////////*/

    function _mint(address to, uint256 amount) internal virtual {
        totalSupply += amount;

        // Cannot overflow because the sum of all user
        // balances can't exceed the max uint256 value.
        unchecked {
            balanceOf[to] += amount;
        }

        emit Transfer(address(0), to, amount);
    }

    function _burn(address from, uint256 amount) internal virtual {
        balanceOf[from] -= amount;

        // Cannot underflow because a user's balance
        // will never be larger than the total supply.
        unchecked {
            totalSupply -= amount;
        }

        emit Transfer(from, address(0), amount);
    }
}

// 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 <0.9.0;

/**
 * @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
}

// 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 <0.9.0;

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

// 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 <0.9.0;

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);
}

// SPDX-License-Identifier: GPL-3.0-or-later

pragma solidity >=0.7.0 <0.9.0;

import "openzeppelin-contracts/contracts/token/ERC20/IERC20.sol";

import "./IVault.sol";

interface IBalancerPoolToken is IERC20 {
    function getVault() external view returns (IVault);
}

// 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 <0.9.0;
pragma experimental ABIEncoderV2;

import "./IBalancerPoolToken.sol";
import "./IPoolSwapStructs.sol";
import "./IVault.sol";

/**
 * @dev Interface for adding and removing liquidity that all Pool contracts should implement. Note that this is not
 * the complete Pool contract interface, as it is missing the swap hooks. Pool contracts should also inherit from
 * either IGeneralPool or IMinimalSwapInfoPool
 */
interface IBasePool is IPoolSwapStructs, IBalancerPoolToken {
    /**
     * @dev Called by the Vault when a user calls `IVault.joinPool` to add liquidity to this Pool. Returns how many of
     * each registered token the user should provide, as well as the amount of protocol fees the Pool owes to the Vault.
     * The Vault will then take tokens from `sender` and add them to the Pool's balances, as well as collect
     * the reported amount in protocol fees, which the pool should calculate based on `protocolSwapFeePercentage`.
     *
     * Protocol fees are reported and charged on join events so that the Pool is free of debt whenever new users join.
     *
     * `sender` is the account performing the join (from which tokens will be withdrawn), and `recipient` is the account
     * designated to receive any benefits (typically pool shares). `balances` contains the total balances
     * for each token the Pool registered in the Vault, in the same order that `IVault.getPoolTokens` would return.
     *
     * `lastChangeBlock` is the last block in which *any* of the Pool's registered tokens last changed its total
     * balance.
     *
     * `userData` contains any pool-specific instructions needed to perform the calculations, such as the type of
     * join (e.g., proportional given an amount of pool shares, single-asset, multi-asset, etc.)
     *
     * Contracts implementing this function should check that the caller is indeed the Vault before performing any
     * state-changing operations, such as minting pool shares.
     */
    function onJoinPool(
        bytes32 poolId,
        address sender,
        address recipient,
        uint256[] memory balances,
        uint256 lastChangeBlock,
        uint256 protocolSwapFeePercentage,
        bytes memory userData
    ) external returns (uint256[] memory amountsIn, uint256[] memory dueProtocolFeeAmounts);

    /**
     * @dev Called by the Vault when a user calls `IVault.exitPool` to remove liquidity from this Pool. Returns how many
     * tokens the Vault should deduct from the Pool's balances, as well as the amount of protocol fees the Pool owes
     * to the Vault. The Vault will then take tokens from the Pool's balances and send them to `recipient`,
     * as well as collect the reported amount in protocol fees, which the Pool should calculate based on
     * `protocolSwapFeePercentage`.
     *
     * Protocol fees are charged on exit events to guarantee that users exiting the Pool have paid their share.
     *
     * `sender` is the account performing the exit (typically the pool shareholder), and `recipient` is the account
     * to which the Vault will send the proceeds. `balances` contains the total token balances for each token
     * the Pool registered in the Vault, in the same order that `IVault.getPoolTokens` would return.
     *
     * `lastChangeBlock` is the last block in which *any* of the Pool's registered tokens last changed its total
     * balance.
     *
     * `userData` contains any pool-specific instructions needed to perform the calculations, such as the type of
     * exit (e.g., proportional given an amount of pool shares, single-asset, multi-asset, etc.)
     *
     * Contracts implementing this function should check that the caller is indeed the Vault before performing any
     * state-changing operations, such as burning pool shares.
     */
    function onExitPool(
        bytes32 poolId,
        address sender,
        address recipient,
        uint256[] memory balances,
        uint256 lastChangeBlock,
        uint256 protocolSwapFeePercentage,
        bytes memory userData
    ) external returns (uint256[] memory amountsOut, uint256[] memory dueProtocolFeeAmounts);

    /**
     * @dev Returns this Pool's ID, used when interacting with the Vault (to e.g. join the Pool or swap with it).
     */
    function getPoolId() external view returns (bytes32);

    /**
     * @dev Returns the current swap fee percentage as a 18 decimal fixed point number, so e.g. 1e17 corresponds to a
     * 10% swap fee.
     */
    function getSwapFeePercentage() external view returns (uint256);

    /**
     * @dev Returns the scaling factors of each of the Pool's tokens. This is an implementation detail that is typically
     * not relevant for outside parties, but which might be useful for some types of Pools.
     */
    function getScalingFactors() external view returns (uint256[] memory);

    function queryJoin(
        bytes32 poolId,
        address sender,
        address recipient,
        uint256[] memory balances,
        uint256 lastChangeBlock,
        uint256 protocolSwapFeePercentage,
        bytes memory userData
    ) external returns (uint256 bptOut, uint256[] memory amountsIn);

    function queryExit(
        bytes32 poolId,
        address sender,
        address recipient,
        uint256[] memory balances,
        uint256 lastChangeBlock,
        uint256 protocolSwapFeePercentage,
        bytes memory userData
    ) external returns (uint256 bptIn, uint256[] memory amountsOut);
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);

    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);

    /**
     * @dev Moves `amount` tokens from the caller's account to `to`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address to, uint256 amount) external returns (bool);

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);

    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);

    /**
     * @dev Moves `amount` tokens from `from` to `to` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(
        address from,
        address to,
        uint256 amount
    ) external returns (bool);
}

// SPDX-License-Identifier: 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 <0.9.0;

// Inspired by Aave Protocol's IFlashLoanReceiver.

import "openzeppelin-contracts/contracts/token/ERC20/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;
}

// SPDX-License-Identifier: GPL-3
pragma solidity 0.8.19;

import { IBasePool } from "src/interfaces/balancer/IBasePool.sol";
import { IRewardPool4626 } from "src/interfaces/aura/IRewardPool4626.sol";

interface IMigrator {
    /**
     * @notice Represents the addresses, migration details, and calculations required for migration
     */
    struct MigrationParams {
        // 80/20 TOKEN/WETH Balancer Pool Token
        IBasePool balancerPoolToken;
        // ERC4626 Aura pool address
        IRewardPool4626 auraPool;
        // Amount of LP tokens to be migrated
        uint256 poolTokensIn;
        // Minimum amount of Tokens to be received from the LP
        uint256 amountCompanionMinimumOut;
        // Minimum amount of WETH to be received from the LP
        uint256 amountWETHMinimumOut;
        // Amount of WETH required to create an 80/20 TOKEN/WETH balance
        uint256 wethRequired;
        // Minimum amount of Tokens from swapping excess WETH due to the 80/20 TOKEN/WETH rebalance (amountWethMin is always > wethRequired)
        uint256 minAmountTokenOut;
        // Amount of BPT to be received given the rebalanced Token and WETH amounts
        uint256 amountBalancerLiquidityOut;
        // Amount of auraBPT to be received given the amount of BPT deposited
        uint256 amountAuraSharesMinimum;
        // Indicates whether to stake the migrated BPT in the Aura pool
        bool stake;
    }

    /**
     * @notice Emitted when an account migrates from UniV2 LP to BPT or auraBPT
     * @param account The account migrating
     * @param poolToken The UniV2 LP token address
     * @param balancerPoolToken The balancer pool address
     * @param poolTokenAmount Amount of UniV2 LP tokens migrated
     * @param balancerPoolTokenAmount The amount of BPT or auraBPT received
     * @param staked Indicates if the account staked BPT in the Aura pool
     */
    event Migrated(
        address indexed account,
        address indexed poolToken,
        address indexed balancerPoolToken,
        uint256 poolTokenAmount,
        uint256 balancerPoolTokenAmount,
        bool staked
    );

    /**
     * @notice Migrate UniV2 LP position into BPT position
     * @param params Migration addresses, details, and calculations
     */
    function migrate(MigrationParams calldata params) external;
}

// 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 <0.9.0;
pragma experimental ABIEncoderV2;

import "openzeppelin-contracts/contracts/token/ERC20/IERC20.sol";

import "./IVault.sol";

interface IPoolSwapStructs {
    // This is not really an interface - it just defines common structs used by other interfaces: IGeneralPool and
    // IMinimalSwapInfoPool.
    //
    // This data structure represents a request for a token swap, where `kind` indicates the swap type ('given in' or
    // 'given out') which indicates whether or not the amount sent by the pool is known.
    //
    // The pool receives `tokenIn` and sends `tokenOut`. `amount` is the number of `tokenIn` tokens the pool will take
    // in, or the number of `tokenOut` tokens the Pool will send out, depending on the given swap `kind`.
    //
    // All other fields are not strictly necessary for most swaps, but are provided to support advanced scenarios in
    // some Pools.
    //
    // `poolId` is the ID of the Pool involved in the swap - this is useful for Pool contracts that implement more than
    // one Pool.
    //
    // The meaning of `lastChangeBlock` depends on the Pool specialization:
    //  - Two Token or Minimal Swap Info: the last block in which either `tokenIn` or `tokenOut` changed its total
    //    balance.
    //  - General: the last block in which *any* of the Pool's registered tokens changed its total balance.
    //
    // `from` is the origin address for the funds the Pool receives, and `to` is the destination address
    // where the Pool sends the outgoing tokens.
    //
    // `userData` is extra data provided by the caller - typically a signature from a trusted party.
    struct SwapRequest {
        IVault.SwapKind kind;
        IERC20 tokenIn;
        IERC20 tokenOut;
        uint256 amount;
        // Misc data
        bytes32 poolId;
        uint256 lastChangeBlock;
        address from;
        address to;
        bytes userData;
    }
}

// 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 <0.9.0;
pragma experimental ABIEncoderV2;

import "openzeppelin-contracts/contracts/token/ERC20/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);
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.15;

interface IRewardPool4626 {
    function withdraw(uint256 assets, address receiver, address owner) external returns (uint256 shares);

    function deposit(uint256 assets, address receiver) external returns (uint256 shares);

    function asset() external view returns (address);

    function balanceOf(address account) external view returns (uint256);

    function processIdleRewards() external;

    function previewDeposit(uint256 assets) external view returns (uint256);
}

// 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 <0.9.0;

/**
 * @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);
}

// 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 <0.9.0;

/**
 * @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
        );
}

// SPDX-License-Identifier: GPL-3.0

pragma solidity >=0.5.0;

interface IUniswapV2Factory {
    event PairCreated(address indexed token0, address indexed token1, address pair, uint);

    function feeTo() external view returns (address);

    function feeToSetter() external view returns (address);

    function getPair(address tokenA, address tokenB) external view returns (address pair);

    function allPairs(uint) external view returns (address pair);

    function allPairsLength() external view returns (uint);

    function createPair(address tokenA, address tokenB) external returns (address pair);

    function setFeeTo(address) external;

    function setFeeToSetter(address) external;
}

// SPDX-License-Identifier: GPL-3.0

pragma solidity >=0.5.0;

interface IUniswapV2Pair {
    event Approval(address indexed owner, address indexed spender, uint value);
    event Transfer(address indexed from, address indexed to, uint value);

    function name() external pure returns (string memory);

    function symbol() external pure returns (string memory);

    function decimals() external pure returns (uint8);

    function totalSupply() external view returns (uint);

    function balanceOf(address owner) external view returns (uint);

    function allowance(address owner, address spender) external view returns (uint);

    function approve(address spender, uint value) external returns (bool);

    function transfer(address to, uint value) external returns (bool);

    function transferFrom(address from, address to, uint value) external returns (bool);

    function DOMAIN_SEPARATOR() external view returns (bytes32);

    function PERMIT_TYPEHASH() external pure returns (bytes32);

    function nonces(address owner) external view returns (uint);

    function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external;

    event Mint(address indexed sender, uint amount0, uint amount1);
    event Burn(address indexed sender, uint amount0, uint amount1, address indexed to);
    event Swap(
        address indexed sender,
        uint amount0In,
        uint amount1In,
        uint amount0Out,
        uint amount1Out,
        address indexed to
    );
    event Sync(uint112 reserve0, uint112 reserve1);

    function MINIMUM_LIQUIDITY() external pure returns (uint);

    function factory() external view returns (address);

    function token0() external view returns (address);

    function token1() external view returns (address);

    function getReserves() external view returns (uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast);

    function price0CumulativeLast() external view returns (uint);

    function price1CumulativeLast() external view returns (uint);

    function kLast() external view returns (uint);

    function mint(address to) external returns (uint liquidity);

    function burn(address to) external returns (uint amount0, uint amount1);

    function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external;

    function skim(address to) external;

    function sync() external;

    function initialize(address, address) external;
}

// SPDX-License-Identifier: GPL-3.0

pragma solidity >=0.6.2;

interface IUniswapV2Router01 {
    function factory() external pure returns (address);

    function WETH() external pure returns (address);

    function addLiquidity(
        address tokenA,
        address tokenB,
        uint amountADesired,
        uint amountBDesired,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB, uint liquidity);

    function addLiquidityETH(
        address token,
        uint amountTokenDesired,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external payable returns (uint amountToken, uint amountETH, uint liquidity);

    function removeLiquidity(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB);

    function removeLiquidityETH(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountToken, uint amountETH);

    function removeLiquidityWithPermit(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline,
        bool approveMax,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external returns (uint amountA, uint amountB);

    function removeLiquidityETHWithPermit(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external returns (uint amountToken, uint amountETH);

    function swapExactTokensForTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);

    function swapTokensForExactTokens(
        uint amountOut,
        uint amountInMax,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);

    function swapExactETHForTokens(
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external payable returns (uint[] memory amounts);

    function swapTokensForExactETH(
        uint amountOut,
        uint amountInMax,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);

    function swapExactTokensForETH(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);

    function swapETHForExactTokens(
        uint amountOut,
        address[] calldata path,
        address to,
        uint deadline
    ) external payable returns (uint[] memory amounts);

    function quote(uint amountA, uint reserveA, uint reserveB) external pure returns (uint amountB);

    function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) external pure returns (uint amountOut);

    function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) external pure returns (uint amountIn);

    function getAmountsOut(uint amountIn, address[] calldata path) external view returns (uint[] memory amounts);

    function getAmountsIn(uint amountOut, address[] calldata path) external view returns (uint[] memory amounts);
}

// SPDX-License-Identifier: GPL-3.0

pragma solidity >=0.6.2;

import "./IUniswapV2Router01.sol";

interface IUniswapV2Router02 is IUniswapV2Router01 {
    function removeLiquidityETHSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountETH);

    function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external returns (uint amountETH);

    function swapExactTokensForTokensSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;

    function swapExactETHForTokensSupportingFeeOnTransferTokens(
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external payable;

    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
}

// 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 "openzeppelin-contracts/contracts/token/ERC20/IERC20.sol";
import "../helpers/IAuthentication.sol";
import "../helpers/ISignaturesValidator.sol";
import "../helpers/ITemporarilyPausable.sol";
import "./IWETH.sol";

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

pragma solidity >=0.7.0 <0.9.0;

/**
 * @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
}

// 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 <0.9.0;

import "openzeppelin-contracts/contracts/token/ERC20/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;
}

// SPDX-License-Identifier: GPL-3
pragma solidity 0.8.19;

import { WETH } from "solmate/src/tokens/WETH.sol";
import { ERC20 } from "solmate/src/tokens/ERC20.sol";
import { IERC20 } from "openzeppelin-contracts/contracts/token/ERC20/IERC20.sol";
import { SafeTransferLib } from "solmate/src/utils/SafeTransferLib.sol";

import { IUniswapV2Pair } from "src/interfaces/univ2/IUniswapV2Pair.sol";
import { IUniswapV2Factory } from "src/interfaces/univ2/IUniswapV2Factory.sol";
import { IUniswapV2Router02 } from "src/interfaces/univ2/IUniswapV2Router02.sol";
import { IAsset } from "src/interfaces/balancer/IAsset.sol";
import { IVault } from "src/interfaces/balancer/IVault.sol";
import { WeightedPoolUserData } from "src/interfaces/balancer/WeightedPoolUserData.sol";

import { IMigrator } from "src/interfaces/IMigrator.sol";

/**
 * @title UniV2 LP to Balancer LP migrator
 * @notice Tool to facilitate migrating UniV2 LPs to Balancer or Aura
 * @dev LP: IUniswapV2Pair LP Token
 * @dev BPT: 20WETH-80TOKEN Balancer Pool Token
 * @dev auraBPT: 20WETH-80TOKEN Aura Deposit Vault
 */
contract Migrator is IMigrator {
    using SafeTransferLib for ERC20;
    
    // WETH token
    WETH public immutable weth;
    // Balancer vault
    IVault public immutable balancerVault;
    // Router for the UniV2 LP token
    IUniswapV2Router02 public immutable router;
    // Factory for the UniV2 LP token
    IUniswapV2Factory public immutable factory;

    constructor(address wethAddress, address balancerVaultAddress, address routerAddress) {
        weth =          WETH(payable(wethAddress));
        balancerVault = IVault(balancerVaultAddress);
        router =        IUniswapV2Router02(routerAddress);
        factory =       IUniswapV2Factory(router.factory());
    }
    
    /**
     * @inheritdoc IMigrator
     */
    function migrate(MigrationParams calldata params) external {
        // If the user is staking, then the Aura pool asset must be the same as the Balancer pool token
        if (params.stake) {
            require(address(params.balancerPoolToken) == params.auraPool.asset(), "Invalid Aura pool");
        }

        // Grab the two tokens in the balancer vault. If the vault has more than two tokens, the migration will fail.
        bytes32 poolId = params.balancerPoolToken.getPoolId();
        (IERC20[] memory balancerPoolTokens, /* uint256[] memory balances */, /* uint256 lastChangeBlock */) = balancerVault.getPoolTokens(poolId);
        require(balancerPoolTokens.length == 2, "Invalid balancer pool");

        // Find the companion token
        IERC20 companionToken;
        if (balancerPoolTokens[0] == IERC20(address(weth))) {
            companionToken = balancerPoolTokens[1];
        } else if (balancerPoolTokens[1] == IERC20(address(weth))) {
            companionToken = balancerPoolTokens[0];
        } else {
            // If neither token is WETH, then the migration will fail
            revert("Balancer pool must contain WETH");
        }

        // Verify there is a matching UniV2 pool (ordering is handled upstream by the factory)
        address poolToken = factory.getPair(address(companionToken), address(weth));

        require(poolToken != address(0), "Pool address verification failed");
        
        // Transfer the pool tokens to this contract before we conduct any mutations
        ERC20(address(poolToken)).safeTransferFrom(msg.sender, address(this), params.poolTokensIn);

        // Check if the pool token has been approved for the router
        if (IUniswapV2Pair(poolToken).allowance(address(this), address(router)) < params.poolTokensIn) {
            ERC20(address(poolToken)).safeApprove(address(router), type(uint256).max);
        }

        // The ordering of `tokenA` and `tokenB` is handled upstream by the router
        router.removeLiquidity({
            tokenA:     address(companionToken),
            tokenB:     address(weth),
            liquidity:  params.poolTokensIn,
            amountAMin: params.amountCompanionMinimumOut,
            amountBMin: params.amountWETHMinimumOut,
            to:         address(this),
            deadline:   block.timestamp
        });

        require(weth.balanceOf(address(this)) > params.wethRequired, "Contract doesn't have enough weth");

        // Check if the WETH token has been approved for the balancer vault
        if (ERC20(address(weth)).allowance(address(this), address(balancerVault)) < weth.balanceOf(address(this))) {
            ERC20(address(weth)).safeApprove(address(balancerVault), type(uint256).max);
        }

        balancerVault.swap({
            singleSwap:  IVault.SingleSwap({
                poolId: poolId,
                kind: IVault.SwapKind.GIVEN_IN,
                assetIn:  IAsset(address(weth)),
                assetOut: IAsset(address(companionToken)),
                // Swap the amount of WETH not needed for the Balancer pool deposit
                amount: weth.balanceOf(address(this)) - params.wethRequired,
                userData: bytes("")
            }),
            funds: IVault.FundManagement({
                sender: address(this),
                fromInternalBalance: false,
                recipient: payable(address(this)),
                toInternalBalance: false
            }),
            limit: params.minAmountTokenOut,
            deadline: block.timestamp
        });

        IAsset[] memory assets = new IAsset[](2);
        assets[0] = IAsset(address(balancerPoolTokens[0]));
        assets[1] = IAsset(address(balancerPoolTokens[1]));

        uint256[] memory maximumAmountsIn = new uint256[](2);
        
        // Make sure the amounts in are in the correct order
        if (balancerPoolTokens[0] == IERC20(address(weth))) {
            maximumAmountsIn[0] = weth.balanceOf(address(this));
            maximumAmountsIn[1] = companionToken.balanceOf(address(this));
        } else {
            maximumAmountsIn[0] = companionToken.balanceOf(address(this));
            maximumAmountsIn[1] = weth.balanceOf(address(this));
        }

        // Approve the balancer vault to spend the companion token
        ERC20(address(companionToken)).safeApprove(address(balancerVault), 0);
        ERC20(address(companionToken)).safeApprove(address(balancerVault), companionToken.balanceOf(address(this)));        

        balancerVault.joinPool({
            poolId: poolId,
            sender: address(this),
            recipient: address(this),
            request: IVault.JoinPoolRequest({
                assets: assets,
                maxAmountsIn: maximumAmountsIn,
                userData: abi.encode(
                    WeightedPoolUserData.JoinKind.EXACT_TOKENS_IN_FOR_BPT_OUT,
                    maximumAmountsIn,
                    params.amountBalancerLiquidityOut
                ),
                fromInternalBalance: false
            })
        });

        // Get the amount of BPT received since joinPool does not return the amount
        uint256 balancerPoolTokensReceived = params.balancerPoolToken.balanceOf(address(this));

        // If the user is staking, we deposit BPT into the Aura pool on the user's behalf
        // Otherwise, we transfer the BPT to the user
        if (params.stake) {
            ERC20(address(params.balancerPoolToken)).safeApprove(address(params.auraPool), balancerPoolTokensReceived);
            uint256 shares = params.auraPool.deposit(balancerPoolTokensReceived, msg.sender);
            require(shares >= params.amountAuraSharesMinimum, "Invalid auraBpt amount out");
        } else {
            ERC20(address(params.balancerPoolToken)).safeTransfer(msg.sender, balancerPoolTokensReceived);
        }

        // Indicate who migrated, UniV2 pool source, balancer pool destination, amounts in and out, and whether the user is staking
        emit Migrated(msg.sender, poolToken, address(params.balancerPoolToken), params.poolTokensIn, balancerPoolTokensReceived, params.stake);
    }
}

// SPDX-License-Identifier: AGPL-3.0-only
pragma solidity >=0.8.0;

import {ERC20} from "../tokens/ERC20.sol";

/// @notice Safe ETH and ERC20 transfer library that gracefully handles missing return values.
/// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/utils/SafeTransferLib.sol)
/// @dev Use with caution! Some functions in this library knowingly create dirty bits at the destination of the free memory pointer.
/// @dev Note that none of the functions in this library check that a token has code at all! That responsibility is delegated to the caller.
library SafeTransferLib {
    /*//////////////////////////////////////////////////////////////
                             ETH OPERATIONS
    //////////////////////////////////////////////////////////////*/

    function safeTransferETH(address to, uint256 amount) internal {
        bool success;

        /// @solidity memory-safe-assembly
        assembly {
            // Transfer the ETH and store if it succeeded or not.
            success := call(gas(), to, amount, 0, 0, 0, 0)
        }

        require(success, "ETH_TRANSFER_FAILED");
    }

    /*//////////////////////////////////////////////////////////////
                            ERC20 OPERATIONS
    //////////////////////////////////////////////////////////////*/

    function safeTransferFrom(
        ERC20 token,
        address from,
        address to,
        uint256 amount
    ) internal {
        bool success;

        /// @solidity memory-safe-assembly
        assembly {
            // Get a pointer to some free memory.
            let freeMemoryPointer := mload(0x40)

            // Write the abi-encoded calldata into memory, beginning with the function selector.
            mstore(freeMemoryPointer, 0x23b872dd00000000000000000000000000000000000000000000000000000000)
            mstore(add(freeMemoryPointer, 4), from) // Append the "from" argument.
            mstore(add(freeMemoryPointer, 36), to) // Append the "to" argument.
            mstore(add(freeMemoryPointer, 68), amount) // Append the "amount" argument.

            success := and(
                // Set success to whether the call reverted, if not we check it either
                // returned exactly 1 (can't just be non-zero data), or had no return data.
                or(and(eq(mload(0), 1), gt(returndatasize(), 31)), iszero(returndatasize())),
                // We use 100 because the length of our calldata totals up like so: 4 + 32 * 3.
                // We use 0 and 32 to copy up to 32 bytes of return data into the scratch space.
                // Counterintuitively, this call must be positioned second to the or() call in the
                // surrounding and() call or else returndatasize() will be zero during the computation.
                call(gas(), token, 0, freeMemoryPointer, 100, 0, 32)
            )
        }

        require(success, "TRANSFER_FROM_FAILED");
    }

    function safeTransfer(
        ERC20 token,
        address to,
        uint256 amount
    ) internal {
        bool success;

        /// @solidity memory-safe-assembly
        assembly {
            // Get a pointer to some free memory.
            let freeMemoryPointer := mload(0x40)

            // Write the abi-encoded calldata into memory, beginning with the function selector.
            mstore(freeMemoryPointer, 0xa9059cbb00000000000000000000000000000000000000000000000000000000)
            mstore(add(freeMemoryPointer, 4), to) // Append the "to" argument.
            mstore(add(freeMemoryPointer, 36), amount) // Append the "amount" argument.

            success := and(
                // Set success to whether the call reverted, if not we check it either
                // returned exactly 1 (can't just be non-zero data), or had no return data.
                or(and(eq(mload(0), 1), gt(returndatasize(), 31)), iszero(returndatasize())),
                // We use 68 because the length of our calldata totals up like so: 4 + 32 * 2.
                // We use 0 and 32 to copy up to 32 bytes of return data into the scratch space.
                // Counterintuitively, this call must be positioned second to the or() call in the
                // surrounding and() call or else returndatasize() will be zero during the computation.
                call(gas(), token, 0, freeMemoryPointer, 68, 0, 32)
            )
        }

        require(success, "TRANSFER_FAILED");
    }

    function safeApprove(
        ERC20 token,
        address to,
        uint256 amount
    ) internal {
        bool success;

        /// @solidity memory-safe-assembly
        assembly {
            // Get a pointer to some free memory.
            let freeMemoryPointer := mload(0x40)

            // Write the abi-encoded calldata into memory, beginning with the function selector.
            mstore(freeMemoryPointer, 0x095ea7b300000000000000000000000000000000000000000000000000000000)
            mstore(add(freeMemoryPointer, 4), to) // Append the "to" argument.
            mstore(add(freeMemoryPointer, 36), amount) // Append the "amount" argument.

            success := and(
                // Set success to whether the call reverted, if not we check it either
                // returned exactly 1 (can't just be non-zero data), or had no return data.
                or(and(eq(mload(0), 1), gt(returndatasize(), 31)), iszero(returndatasize())),
                // We use 68 because the length of our calldata totals up like so: 4 + 32 * 2.
                // We use 0 and 32 to copy up to 32 bytes of return data into the scratch space.
                // Counterintuitively, this call must be positioned second to the or() call in the
                // surrounding and() call or else returndatasize() will be zero during the computation.
                call(gas(), token, 0, freeMemoryPointer, 68, 0, 32)
            )
        }

        require(success, "APPROVE_FAILED");
    }
}

// SPDX-License-Identifier: AGPL-3.0-only
pragma solidity >=0.8.0;

import {ERC20} from "./ERC20.sol";

import {SafeTransferLib} from "../utils/SafeTransferLib.sol";

/// @notice Minimalist and modern Wrapped Ether implementation.
/// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/tokens/WETH.sol)
/// @author Inspired by WETH9 (https://github.com/dapphub/ds-weth/blob/master/src/weth9.sol)
contract WETH is ERC20("Wrapped Ether", "WETH", 18) {
    using SafeTransferLib for address;

    event Deposit(address indexed from, uint256 amount);

    event Withdrawal(address indexed to, uint256 amount);

    function deposit() public payable virtual {
        _mint(msg.sender, msg.value);

        emit Deposit(msg.sender, msg.value);
    }

    function withdraw(uint256 amount) public virtual {
        _burn(msg.sender, amount);

        emit Withdrawal(msg.sender, amount);

        msg.sender.safeTransferETH(amount);
    }

    receive() external payable virtual {
        deposit();
    }
}

// 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 <0.9.0;

import "openzeppelin-contracts/contracts/token/ERC20/IERC20.sol";

library WeightedPoolUserData {
    // In order to preserve backwards compatibility, make sure new join and exit kinds are added at the end of the enum.
    enum JoinKind {
        INIT,
        EXACT_TOKENS_IN_FOR_BPT_OUT,
        TOKEN_IN_FOR_EXACT_BPT_OUT,
        ALL_TOKENS_IN_FOR_EXACT_BPT_OUT
    }
    enum ExitKind {
        EXACT_BPT_IN_FOR_ONE_TOKEN_OUT,
        EXACT_BPT_IN_FOR_TOKENS_OUT,
        BPT_IN_FOR_EXACT_TOKENS_OUT
    }

    function joinKind(bytes memory self) internal pure returns (JoinKind) {
        return abi.decode(self, (JoinKind));
    }

    function exitKind(bytes memory self) internal pure returns (ExitKind) {
        return abi.decode(self, (ExitKind));
    }

    // Joins

    function initialAmountsIn(bytes memory self) internal pure returns (uint256[] memory amountsIn) {
        (, amountsIn) = abi.decode(self, (JoinKind, uint256[]));
    }

    function exactTokensInForBptOut(bytes memory self)
        internal
        pure
        returns (uint256[] memory amountsIn, uint256 minBPTAmountOut)
    {
        (, amountsIn, minBPTAmountOut) = abi.decode(self, (JoinKind, uint256[], uint256));
    }

    function tokenInForExactBptOut(bytes memory self) internal pure returns (uint256 bptAmountOut, uint256 tokenIndex) {
        (, bptAmountOut, tokenIndex) = abi.decode(self, (JoinKind, uint256, uint256));
    }

    function allTokensInForExactBptOut(bytes memory self) internal pure returns (uint256 bptAmountOut) {
        (, bptAmountOut) = abi.decode(self, (JoinKind, uint256));
    }

    // Exits

    function exactBptInForTokenOut(bytes memory self) internal pure returns (uint256 bptAmountIn, uint256 tokenIndex) {
        (, bptAmountIn, tokenIndex) = abi.decode(self, (ExitKind, uint256, uint256));
    }

    function exactBptInForTokensOut(bytes memory self) internal pure returns (uint256 bptAmountIn) {
        (, bptAmountIn) = abi.decode(self, (ExitKind, uint256));
    }

    function bptInForExactTokensOut(bytes memory self)
        internal
        pure
        returns (uint256[] memory amountsOut, uint256 maxBPTAmountIn)
    {
        (, amountsOut, maxBPTAmountIn) = abi.decode(self, (ExitKind, uint256[], uint256));
    }
}

{
  "compilationTarget": {
    "src/Migrator.sol": "Migrator"
  },
  "evmVersion": "paris",
  "libraries": {},
  "metadata": {
    "bytecodeHash": "ipfs"
  },
  "optimizer": {
    "enabled": true,
    "runs": 200
  },
  "remappings": [
    ":ds-test/=lib/forge-std/lib/ds-test/src/",
    ":forge-std/=lib/forge-std/src/",
    ":openzeppelin-contracts/=lib/openzeppelin-contracts/",
    ":openzeppelin-contracts/contracts/=lib/openzeppelin-contracts/contracts/",
    ":solmate/=lib/solmate/"
  ]
}