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

interface IManagedPool is IBasePool {
    event GradualSwapFeeUpdateScheduled(
        uint256 startTime,
        uint256 endTime,
        uint256 startSwapFeePercentage,
        uint256 endSwapFeePercentage
    );
    event GradualWeightUpdateScheduled(
        uint256 startTime,
        uint256 endTime,
        uint256[] startWeights,
        uint256[] endWeights
    );
    event SwapEnabledSet(bool swapEnabled);
    event JoinExitEnabledSet(bool joinExitEnabled);
    event MustAllowlistLPsSet(bool mustAllowlistLPs);
    event AllowlistAddressAdded(address indexed member);
    event AllowlistAddressRemoved(address indexed member);
    event ManagementAumFeePercentageChanged(uint256 managementAumFeePercentage);
    event ManagementAumFeeCollected(uint256 bptAmount);
    event CircuitBreakerSet(
        IERC20 indexed token,
        uint256 bptPrice,
        uint256 lowerBoundPercentage,
        uint256 upperBoundPercentage
    );
    event TokenAdded(IERC20 indexed token, uint256 normalizedWeight);
    event TokenRemoved(IERC20 indexed token);

    /**
     * @notice Returns the effective BPT supply.
     *
     * @dev The Pool owes debt to the Protocol and the Pool's owner in the form of unminted BPT, which will be minted
     * immediately before the next join or exit. We need to take these into account since, even if they don't yet exist,
     * they will effectively be included in any Pool operation that involves BPT.
     *
     * In the vast majority of cases, this function should be used instead of `totalSupply()`.
     *
     * WARNING: since this function reads balances directly from the Vault, it is potentially subject to manipulation
     * via reentrancy. See https://forum.balancer.fi/t/reentrancy-vulnerability-scope-expanded/4345 for reference.
     *
     * To call this function safely, attempt to trigger the reentrancy guard in the Vault by calling a non-reentrant
     * function before calling `getActualSupply`. That will make the transaction revert in an unsafe context.
     * (See `whenNotInVaultContext` in `ManagedPoolSettings`).
     */
    function getActualSupply() external view returns (uint256);

    // Swap fee percentage

    /**
     * @notice Schedule a gradual swap fee update.
     * @dev The swap fee will change from the given starting value (which may or may not be the current
     * value) to the given ending fee percentage, over startTime to endTime.
     *
     * Note that calling this with a starting swap fee different from the current value will immediately change the
     * current swap fee to `startSwapFeePercentage`, before commencing the gradual change at `startTime`.
     * Emits the GradualSwapFeeUpdateScheduled event.
     * This is a permissioned function.
     *
     * @param startTime - The timestamp when the swap fee change will begin.
     * @param endTime - The timestamp when the swap fee change will end (must be >= startTime).
     * @param startSwapFeePercentage - The starting value for the swap fee change.
     * @param endSwapFeePercentage - The ending value for the swap fee change. If the current timestamp >= endTime,
     * `getSwapFeePercentage()` will return this value.
     */
    function updateSwapFeeGradually(
        uint256 startTime,
        uint256 endTime,
        uint256 startSwapFeePercentage,
        uint256 endSwapFeePercentage
    ) external;

    /**
     * @notice Returns the current gradual swap fee update parameters.
     * @dev The current swap fee can be retrieved via `getSwapFeePercentage()`.
     * @return startTime - The timestamp when the swap fee update will begin.
     * @return endTime - The timestamp when the swap fee update will end.
     * @return startSwapFeePercentage - The starting swap fee percentage (could be different from the current value).
     * @return endSwapFeePercentage - The final swap fee percentage, when the current timestamp >= endTime.
     */
    function getGradualSwapFeeUpdateParams()
        external
        view
        returns (
            uint256 startTime,
            uint256 endTime,
            uint256 startSwapFeePercentage,
            uint256 endSwapFeePercentage
        );

    // Token weights

    /**
     * @notice Schedule a gradual weight change.
     * @dev The weights will change from their current values to the given endWeights, over startTime to endTime.
     * This is a permissioned function.
     *
     * Since, unlike with swap fee updates, we generally do not want to allow instantaneous weight changes,
     * the weights always start from their current values. This also guarantees a smooth transition when
     * updateWeightsGradually is called during an ongoing weight change.
     * @param startTime - The timestamp when the weight change will begin.
     * @param endTime - The timestamp when the weight change will end (can be >= startTime).
     * @param tokens - The tokens associated with the target weights (must match the current pool tokens).
     * @param endWeights - The target weights. If the current timestamp >= endTime, `getNormalizedWeights()`
     * will return these values.
     */
    function updateWeightsGradually(
        uint256 startTime,
        uint256 endTime,
        IERC20[] memory tokens,
        uint256[] memory endWeights
    ) external;

    /**
     * @notice Returns all normalized weights, in the same order as the Pool's tokens.
     */
    function getNormalizedWeights() external view returns (uint256[] memory);

    /**
     * @notice Returns the current gradual weight change update parameters.
     * @dev The current weights can be retrieved via `getNormalizedWeights()`.
     * @return startTime - The timestamp when the weight update will begin.
     * @return endTime - The timestamp when the weight update will end.
     * @return startWeights - The starting weights, when the weight change was initiated.
     * @return endWeights - The final weights, when the current timestamp >= endTime.
     */
    function getGradualWeightUpdateParams()
        external
        view
        returns (
            uint256 startTime,
            uint256 endTime,
            uint256[] memory startWeights,
            uint256[] memory endWeights
        );

    // Join and Exit enable/disable

    /**
     * @notice Enable or disable joins and exits. Note that this does not affect Recovery Mode exits.
     * @dev Emits the JoinExitEnabledSet event. This is a permissioned function.
     * @param joinExitEnabled - The new value of the join/exit enabled flag.
     */
    function setJoinExitEnabled(bool joinExitEnabled) external;

    /**
     * @notice Returns whether joins and exits are enabled.
     */
    function getJoinExitEnabled() external view returns (bool);

    // Swap enable/disable

    /**
     * @notice Enable or disable trading.
     * @dev Emits the SwapEnabledSet event. This is a permissioned function.
     * @param swapEnabled - The new value of the swap enabled flag.
     */
    function setSwapEnabled(bool swapEnabled) external;

    /**
     * @notice Returns whether swaps are enabled.
     */
    function getSwapEnabled() external view returns (bool);

    // LP Allowlist

    /**
     * @notice Enable or disable the LP allowlist.
     * @dev Note that any addresses added to the allowlist will be retained if the allowlist is toggled off and
     * back on again, because this action does not affect the list of LP addresses.
     * Emits the MustAllowlistLPsSet event. This is a permissioned function.
     * @param mustAllowlistLPs - The new value of the mustAllowlistLPs flag.
     */
    function setMustAllowlistLPs(bool mustAllowlistLPs) external;

    /**
     * @notice Adds an address to the LP allowlist.
     * @dev Will fail if the address is already allowlisted.
     * Emits the AllowlistAddressAdded event. This is a permissioned function.
     * @param member - The address to be added to the allowlist.
     */
    function addAllowedAddress(address member) external;

    /**
     * @notice Removes an address from the LP allowlist.
     * @dev Will fail if the address was not previously allowlisted.
     * Emits the AllowlistAddressRemoved event. This is a permissioned function.
     * @param member - The address to be removed from the allowlist.
     */
    function removeAllowedAddress(address member) external;

    /**
     * @notice Returns whether the allowlist for LPs is enabled.
     */
    function getMustAllowlistLPs() external view returns (bool);

    /**
     * @notice Check whether an LP address is on the allowlist.
     * @dev This simply checks the list, regardless of whether the allowlist feature is enabled.
     * @param member - The address to check against the allowlist.
     * @return true if the given address is on the allowlist.
     */
    function isAddressOnAllowlist(address member) external view returns (bool);

    // Management fees

    /**
     * @notice Collect any accrued AUM fees and send them to the pool manager.
     * @dev This can be called by anyone to collect accrued AUM fees - and will be called automatically
     * whenever the supply changes (e.g., joins and exits, add and remove token), and before the fee
     * percentage is changed by the manager, to prevent fees from being applied retroactively.
     *
     * Correct behavior depends on the current supply, which is potentially manipulable if the pool
     * is reentered during execution of a Vault hook. This is protected where overridden in ManagedPoolSettings,
     * and so is safe to call on ManagedPool.
     *
     * See https://forum.balancer.fi/t/reentrancy-vulnerability-scope-expanded/4345 for reference.
     *
     * @return The amount of BPT minted to the manager.
     */
    function collectAumManagementFees() external returns (uint256);

    /**
     * @notice Setter for the yearly percentage AUM management fee, which is payable to the pool manager.
     * @dev Attempting to collect AUM fees in excess of the maximum permitted percentage will revert.
     * To avoid retroactive fee increases, we force collection at the current fee percentage before processing
     * the update. Emits the ManagementAumFeePercentageChanged event. This is a permissioned function.
     *
     * To prevent changing management fees retroactively, this triggers payment of protocol fees before applying
     * the change. Correct behavior depends on the current supply, which is potentially manipulable if the pool
     * is reentered during execution of a Vault hook. This is protected where overridden in ManagedPoolSettings,
     * and so is safe to call on ManagedPool.
     *
     * See https://forum.balancer.fi/t/reentrancy-vulnerability-scope-expanded/4345 for reference.
     *
     * @param managementAumFeePercentage - The new management AUM fee percentage.
     * @return amount - The amount of BPT minted to the manager before the update, if any.
     */
    function setManagementAumFeePercentage(uint256 managementAumFeePercentage) external returns (uint256);

    /**
     * @notice Returns the management AUM fee percentage as an 18-decimal fixed point number and the timestamp of the
     * last collection of AUM fees.
     */
    function getManagementAumFeeParams()
        external
        view
        returns (uint256 aumFeePercentage, uint256 lastCollectionTimestamp);

    // Circuit Breakers

    /**
     * @notice Set a circuit breaker for one or more tokens.
     * @dev This is a permissioned function. The lower and upper bounds are percentages, corresponding to a
     * relative change in the token's spot price: e.g., a lower bound of 0.8 means the breaker should prevent
     * trades that result in the value of the token dropping 20% or more relative to the rest of the pool.
     */
    function setCircuitBreakers(
        IERC20[] memory tokens,
        uint256[] memory bptPrices,
        uint256[] memory lowerBoundPercentages,
        uint256[] memory upperBoundPercentages
    ) external;

    /**
     * @notice Return the full circuit breaker state for the given token.
     * @dev These are the reference values (BPT price and reference weight) passed in when the breaker was set,
     * along with the percentage bounds. It also returns the current BPT price bounds, needed to check whether
     * the circuit breaker should trip.
     */
    function getCircuitBreakerState(IERC20 token)
        external
        view
        returns (
            uint256 bptPrice,
            uint256 referenceWeight,
            uint256 lowerBound,
            uint256 upperBound,
            uint256 lowerBptPriceBound,
            uint256 upperBptPriceBound
        );

    // Add/remove tokens

    /**
     * @notice Adds a token to the Pool's list of tradeable tokens. This is a permissioned function.
     *
     * @dev By adding a token to the Pool's composition, the weights of all other tokens will be decreased. The new
     * token will have no balance - it is up to the owner to provide some immediately after calling this function.
     * Note however that regular join functions will not work while the new token has no balance: the only way to
     * deposit an initial amount is by using an Asset Manager.
     *
     * Token addition is forbidden during a weight change, or if one is scheduled to happen in the future.
     *
     * The caller may additionally pass a non-zero `mintAmount` to have some BPT be minted for them, which might be
     * useful in some scenarios to account for the fact that the Pool will have more tokens.
     *
     * Emits the TokenAdded event. This is a permissioned function.
     *
     * Correct behavior depends on the token balances from the Vault, which may be out of sync with the state of
     * the pool during execution of a Vault hook. This is protected where overridden in ManagedPoolSettings,
     * and so is safe to call on ManagedPool.
     *
     * See https://forum.balancer.fi/t/reentrancy-vulnerability-scope-expanded/4345 for reference.
     *
     * @param tokenToAdd - The ERC20 token to be added to the Pool.
     * @param assetManager - The Asset Manager for the token.
     * @param tokenToAddNormalizedWeight - The normalized weight of `token` relative to the other tokens in the Pool.
     * @param mintAmount - The amount of BPT to be minted as a result of adding `token` to the Pool.
     * @param recipient - The address to receive the BPT minted by the Pool.
     */
    function addToken(
        IERC20 tokenToAdd,
        address assetManager,
        uint256 tokenToAddNormalizedWeight,
        uint256 mintAmount,
        address recipient
    ) external;

    /**
     * @notice Removes a token from the Pool's list of tradeable tokens.
     * @dev Tokens can only be removed if the Pool has more than 2 tokens, as it can never have fewer than 2 (not
     * including BPT). Token removal is also forbidden during a weight change, or if one is scheduled to happen in
     * the future.
     *
     * Emits the TokenRemoved event. This is a permissioned function.
     * Correct behavior depends on the token balances from the Vault, which may be out of sync with the state of
     * the pool during execution of a Vault hook. This is protected where overridden in ManagedPoolSettings,
     * and so is safe to call on ManagedPool.
     *
     * See https://forum.balancer.fi/t/reentrancy-vulnerability-scope-expanded/4345 for reference.
     *
     * The caller may additionally pass a non-zero `burnAmount` to burn some of their BPT, which might be useful
     * in some scenarios to account for the fact that the Pool now has fewer tokens. This is a permissioned function.
     * @param tokenToRemove - The ERC20 token to be removed from the Pool.
     * @param burnAmount - The amount of BPT to be burned after removing `token` from the Pool.
     * @param sender - The address to burn BPT from.
     */
    function removeToken(
        IERC20 tokenToRemove,
        uint256 burnAmount,
        address sender
    ) external;
}