// SPDX-License-Identifier: AGPL-3.0-only

pragma solidity 0.8.10;

import {DataTypes} from '../libraries/DataTypes.sol';

/**
 * @title IFollowNFT
 * @author Lens Protocol
 *
 * @notice This is the interface for the FollowNFT contract, which is cloned upon the first follow for any profile.
 */
interface IFollowNFT {
    /**
     * @notice Initializes the follow NFT, setting the feed as the privileged minter, initializing the name and
     * symbol in the LensNFTBase contract.
     *
     * @param profileId The token ID of the profile in the hub associated with this followNFT, used for transfer hooks.
     * @param name The name to set for this NFT.
     * @param symbol The symbol to set for this NFT.
     */
    function initialize(
        uint256 profileId,
        string calldata name,
        string calldata symbol
    ) external;

    /**
     * @notice Mints a follow NFT to the specified address. This can only be called by the hub, and is called
     * upon follow.
     *
     * @param to The address to mint the NFT to.
     */
    function mint(address to) external;

    /**
     * @notice Delegates the caller's governance power to the given delegatee address.
     *
     * @param delegatee The delegatee address to delegate governance power to.
     */
    function delegate(address delegatee) external;

    /**
     * @notice Delegates the delegator's governance power via meta-tx to the given delegatee address.
     *
     * @param delegator The delegator address, who is the signer.
     * @param delegatee The delegatee address, who is receiving the governance power delegation.
     * @param sig The EIP712Signature struct containing the necessary parameters to recover the delegator's signature.
     */
    function delegateBySig(
        address delegator,
        address delegatee,
        DataTypes.EIP712Signature calldata sig
    ) external;

    /**
     * @notice Returns the governance power for a given user at a specified block number.
     *
     * @param user The user to query governance power for.
     * @param blockNumber The block number to query the user's governance power at.
     */
    function getPowerByBlockNumber(address user, uint256 blockNumber) external returns (uint256);

    /**
     * @notice Returns the total delegated supply at a specified block number. This is the sum of all
     * current available voting power at a given block.
     *
     * @param blockNumber The block number to query the delegated supply at.
     */
    function getDelegatedSupplyByBlockNumber(uint256 blockNumber) external returns (uint256);

}