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// SPDX-License-Identifier: MIT
pragma solidity ^0.8.18;
import "@openzeppelin/contracts/token/ERC20/extensions/ERC20Votes.sol";

abstract contract ERC20VotesEscrowed is ERC20Votes {

function getAddresses() internal view virtual returns(address[] memory);

function escrowBalance(address holder) internal view virtual returns(uint256);

// to be called after tokens have been transferred to this escrow contract
    function setUpVotingPower() internal {
        address[] memory addresses = getAddresses();

for (uint i = 0; i < addresses.length; i++) {
            address a = addresses[i];
            _jankyMoveVotingPower(address(this), a, escrowBalance(a));
        }
    }

function _afterTokenTransfer(address _from, address _to, uint256 _amount) internal override {
        // if it's the escrow contract, don't transfer any voting power when it leaves escrow, the 
        // power will remain with whoever it's been delegated to already
        if (address(this) != _from) {
            super._afterTokenTransfer(_from, _to, _amount);
        }
    }

function _delegate(address _delegator, address _delegatee) internal override {
        super._delegate(_delegator, _delegatee);

// adds the escrow balance to the new delegatee's voting power
        address currentDelegate = delegates(_delegator);
        uint256 escrow = escrowBalance(_delegator);
        _jankyMoveVotingPower(currentDelegate, _delegatee, escrow);
    }

// Moves voting power with the normally private `_moveVotingPower` function 
    // by calling the `_afterTokenTransfer` function.
    //
    // see https://github.com/OpenZeppelin/openzeppelin-contracts/blob/dfef6a68ee18dbd2e1f5a099061a3b8a0e404485/contracts/token/ERC20/extensions/ERC20Votes.sol#LL217C6-L217C6
    // see https://github.com/OpenZeppelin/openzeppelin-contracts/blob/dfef6a68ee18dbd2e1f5a099061a3b8a0e404485/contracts/token/ERC20/ERC20.sol#L364
    function _jankyMoveVotingPower(address _src, address _dst, uint256 _amount) internal {
        super._afterTokenTransfer(_src, _dst, _amount);
    }
}