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// The cut part of the code
pragma solidity ^0.6.12;

import "./Context.sol";
import "./SafeMath.sol";
import "./Ownable.sol";
import "../interfaces/IERC20.sol";

abstract contract ReflectToken is Context, IERC20, Ownable {
    using SafeMath for uint256;

mapping (address => uint256) private _rOwned;
    mapping (address => uint256) private _tOwned;
    mapping (address => mapping (address => uint256)) private _allowances;

mapping (address => bool) private _isExcluded;
    address[] private _excluded;

uint8 private constant _decimals = 18;
    uint256 private _tTotal;
    uint256 private _rTotal;
    uint256 private _tFeeTotal;

string private _name;
    string private _symbol;

/**
     * @dev Sets the values for {name} and {symbol}.
     *
     * The default value of {decimals} is 18. To select a different value for
     * {decimals} you should overload it.
     *
     * All two of these values are immutable: they can only be set once during
     * construction.
     */
    constructor (string memory name_, string memory symbol_, uint256 tTotal_) public {
        _name = name_;
        _symbol = symbol_;
        _tTotal = tTotal_;
        uint256 MAX = type(uint256).max;
        _rTotal = (MAX - (MAX % _tTotal));
        _rOwned[_msgSender()] = _rTotal;
        emit Transfer(address(0), _msgSender(), _tTotal);
    }

/**
     * @dev Amount of tokens to be charged as a reflection fee. Must be in range 0..amount.
     */
    function _calculateReflectionFee(address sender, address recipient, uint256 amount) internal virtual view returns (uint256);

/**
     * @dev Amount of tokens to be charged and stored in this contract. Must be in range 0..amount.
     */
    function _calculateAccumulationFee(address sender, address recipient, uint256 amount) internal virtual view returns (uint256);

/**
     * @dev Distributes reflection rewards.
     * @param rFee Fee taken from the sender"s account.
     * @param tFee Fee with considering of a rate (real amount of tokens).
     */
    function _reflectFee(uint256 rFee, uint256 tFee) private {
        _rTotal = _rTotal.sub(rFee);
        _tFeeTotal = _tFeeTotal.add(tFee);
    }

/**
     * @dev Accumulates accumulation fee on the contract"s balance with considering of its involvement in rewards reflection.
     */
    function _accumulateFee(uint256 rAccumulation, uint256 tAccumulation) private {
        _rOwned[address(this)] = _rOwned[address(this)].add(rAccumulation);
        if(_isExcluded[address(this)]) {
            _tOwned[address(this)] = _tOwned[address(this)].add(tAccumulation);
        }
    }

/**
     * @dev Returns results of `_getTValues` and `_getRValues` methods.
     */
    function _getValues(address sender, address recipient, uint256 tAmount) private view returns (uint256, uint256, uint256, uint256, uint256, uint256, uint256) {
        (uint256 tTransferAmount, uint256 tFee, uint256 tAccumulation) = _getTValues(sender, recipient, tAmount);
        (uint256 rAmount, uint256 rTransferAmount, uint256 rFee, uint256 rAccumulation) = _getRValues(tAmount, tFee, tAccumulation);
        return (rAmount, rTransferAmount, rFee, rAccumulation, tTransferAmount, tFee, tAccumulation);
    }

/**
     * @dev Computes and returns transfer amount, reflection fee, accumulation fee in tokens.
     */
    function _getTValues(address sender, address recipient, uint256 tAmount) private view returns (uint256, uint256, uint256) {
        uint256 tFee = _calculateReflectionFee(sender, recipient, tAmount);
        uint256 tAccumulation = _calculateAccumulationFee(sender, recipient, tAmount);
        uint256 tTransferAmount = tAmount.sub(tFee).sub(tAccumulation);
        return (tTransferAmount, tFee, tAccumulation);
    }

/**
     * @dev Computes and returns amount, transfer amount, reflection fee, accumulation fee in reflection.
     */
    function _getRValues(uint256 tAmount, uint256 tFee, uint256 tAccumulation) private view returns (uint256, uint256, uint256, uint256) {
        uint256 currentRate = _getRate();
        uint256 rAmount = tAmount.mul(currentRate);
        uint256 rFee = tFee.mul(currentRate);
        uint256 rAccumulation = tAccumulation.mul(currentRate);
        uint256 rTransferAmount = rAmount.sub(rFee).sub(rAccumulation);
        return (rAmount, rTransferAmount, rFee, rAccumulation);
    }

/**
     * @dev Returns reflection to token rate.
     */
    function _getRate() private view returns(uint256) {
        (uint256 rSupply, uint256 tSupply) = _getCurrentSupply();
        return rSupply.div(tSupply);
    }

/**
     * @dev Returns current supply.
     */
    function _getCurrentSupply() private view returns(uint256, uint256) {
        uint256 rSupply = _rTotal;
        uint256 tSupply = _tTotal;
        uint256 len = _excluded.length;
        for (uint256 i = 0; i < len; i++) {
            address account = _excluded[i];
            uint256 rBalance = _rOwned[account];
            uint256 tBalance = _tOwned[account];
            if (rBalance > rSupply || tBalance > tSupply) return (_rTotal, _tTotal);
            rSupply = rSupply.sub(rBalance);
            tSupply = tSupply.sub(tBalance);
        }
        if (rSupply < _rTotal.div(_tTotal)) return (_rTotal, _tTotal);
        return (rSupply, tSupply);
    }
}