IVotes.sol

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (governance/utils/IVotes.sol)
pragma solidity ^0.8.20;

/**
 * @dev Common interface for {ERC20Votes}, {ERC721Votes}, and other {Votes}-enabled contracts.
 */
interface IVotes {
    /**
     * @dev The signature used has expired.
     */
    error VotesExpiredSignature(uint256 expiry);

    /**
     * @dev Emitted when an account changes their delegate.
     */
    event DelegateChanged(address indexed delegator, address indexed fromDelegate, address indexed toDelegate);

    /**
     * @dev Emitted when a token transfer or delegate change results in changes to a delegate's number of voting units.
     */
    event DelegateVotesChanged(address indexed delegate, uint256 previousVotes, uint256 newVotes);

    /**
     * @dev Returns the current amount of votes that `account` has.
     */
    function getVotes(address account) external view returns (uint256);

    /**
     * @dev Returns the amount of votes that `account` had at a specific moment in the past. If the `clock()` is
     * configured to use block numbers, this will return the value at the end of the corresponding block.
     */
    function getPastVotes(address account, uint256 timepoint) external view returns (uint256);

    /**
     * @dev Returns the total supply of votes available at a specific moment in the past. If the `clock()` is
     * configured to use block numbers, this will return the value at the end of the corresponding block.
     *
     * NOTE: This value is the sum of all available votes, which is not necessarily the sum of all delegated votes.
     * Votes that have not been delegated are still part of total supply, even though they would not participate in a
     * vote.
     */
    function getPastTotalSupply(uint256 timepoint) external view returns (uint256);

    /**
     * @dev Returns the delegate that `account` has chosen.
     */
    function delegates(address account) external view returns (address);

    /**
     * @dev Delegates votes from the sender to `delegatee`.
     */
    function delegate(address delegatee) external;

    /**
     * @dev Delegates votes from signer to `delegatee`.
     */
    function delegateBySig(address delegatee, uint256 nonce, uint256 expiry, uint8 v, bytes32 r, bytes32 s) external;
}