/**
*
*/

// SPDX-License-Identifier: MIT
//
// Fair Tree is an all-inclusive ecosystem that is dedicated to the people. Run by an experienced team of developers we are on a mission to protect the Amazon Rainforest.
//


pragma solidity ^0.8.4;

// IERC20 interface taken from: https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/token/ERC20/IERC20.sol)
interface IERC20 {
function totalSupply() external view returns (uint256);
function balanceOf(address account) external view returns (uint256);
function transfer(address recipient, uint256 amount) external returns (bool);
function allowance(address owner, address spender) external view returns (uint256);
function approve(address spender, uint256 amount) external returns (bool);
function transferFrom(
address sender,
address recipient,
uint256 amount
) external returns (bool);
event Transfer(address indexed from, address indexed to, uint256 value);
event Approval(address indexed owner, address indexed spender, uint256 value);
}

// Context abstract contract taken from https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/utils/Context.sol
abstract contract Context {
function _msgSender() internal view virtual returns (address) {
return msg.sender;
}

function _msgData() internal view virtual returns (bytes calldata) {
return msg.data;
}
}

// SafeMath library taken from https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/utils/math/SafeMath.sol
library SafeMath {

function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a b;
require(c >= a, "SafeMath: addition overflow");

return c;
}

function sub(uint256 a, uint256 b) internal pure returns (uint256) {
return sub(a, b, "SafeMath: subtraction overflow");
}

function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
require(b <= a, errorMessage);
uint256 c = a - b;

return c;
}

function mul(uint256 a, uint256 b) internal pure returns (uint256) {
if (a == 0) {
return 0;
}

uint256 c = a * b;
require(c / a == b, "SafeMath: multiplication overflow");

return c;
}


function div(uint256 a, uint256 b) internal pure returns (uint256) {
return div(a, b, "SafeMath: division by zero");
}

function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
require(b > 0, errorMessage);
uint256 c = a / b;
// assert(a == b * c a % b); // There is no case in which this doesn't hold

return c;
}

function mod(uint256 a, uint256 b) internal pure returns (uint256) {
return mod(a, b, "SafeMath: modulo by zero");
}

function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
require(b != 0, errorMessage);
return a % b;
}
}

// Address library taken from https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/utils/Address.sol
library Address {
function isContract(address account) internal view returns (bool) {
// This method relies on extcodesize, which returns 0 for contracts in
// construction, since the code is only stored at the end of the
// constructor execution.

uint256 size;
assembly {
size := extcodesize(account)
}
return size > 0;
}

function sendValue(address payable recipient, uint256 amount) internal {
require(address(this).balance >= amount, "Address: insufficient balance");

(bool success, ) = recipient.call{value: amount}("");
require(success, "Address: unable to send value, recipient may have reverted");
}

function functionCall(address target, bytes memory data) internal returns (bytes memory) {
return functionCall(target, data, "Address: low-level call failed");
}

function functionCall(
address target,
bytes memory data,
string memory errorMessage
) internal returns (bytes memory) {
return functionCallWithValue(target, data, 0, errorMessage);
}

function functionCallWithValue(
address target,
bytes memory data,
uint256 value
) internal returns (bytes memory) {
return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
}

function functionCallWithValue(
address target,
bytes memory data,
uint256 value,
string memory errorMessage
) internal returns (bytes memory) {
require(address(this).balance >= value, "Address: insufficient balance for call");
require(isContract(target), "Address: call to non-contract");

(bool success, bytes memory returndata) = target.call{value: value}(data);
return _verifyCallResult(success, returndata, errorMessage);
}

function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
return functionStaticCall(target, data, "Address: low-level static call failed");
}

function functionStaticCall(
address target,
bytes memory data,
string memory errorMessage
) internal view returns (bytes memory) {
require(isContract(target), "Address: static call to non-contract");

(bool success, bytes memory returndata) = target.staticcall(data);
return _verifyCallResult(success, returndata, errorMessage);
}

function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
return functionDelegateCall(target, data, "Address: low-level delegate call failed");
}

function functionDelegateCall(
address target,
bytes memory data,
string memory errorMessage
) internal returns (bytes memory) {
require(isContract(target), "Address: delegate call to non-contract");

(bool success, bytes memory returndata) = target.delegatecall(data);
return _verifyCallResult(success, returndata, errorMessage);
}

function _verifyCallResult(
bool success,
bytes memory returndata,
string memory errorMessage
) private pure returns (bytes memory) {
if (success) {
return returndata;
} else {
// Look for revert reason and bubble it up if present
if (returndata.length > 0) {
// The easiest way to bubble the revert reason is using memory via assembly

assembly {
let returndata_size := mload(returndata)
revert(add(32, returndata), returndata_size)
}
} else {
revert(errorMessage);
}
}
}
}

// Ownable abstract contract taken from https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/access/Ownable.sol
abstract contract Ownable is Context {
address private _owner;

event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

/**
* @dev Initializes the contract setting the deployer as the initial owner.
*/
constructor() {
_setOwner(_msgSender());
}

/**
* @dev Returns the address of the current owner.
*/
function owner() public view virtual returns (address) {
return _owner;
}

/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
require(owner() == _msgSender(), "Ownable: caller is not the owner");
_;
}

/**
* @dev Leaves the contract without owner. It will not be possible to call
* `onlyOwner` functions anymore. Can only be called by the current owner.
*
* NOTE: Renouncing ownership will leave the contract without an owner,
* thereby removing any functionality that is only available to the owner.
*/
function renounceOwnership() public virtual onlyOwner {
_setOwner(address(0));
}

/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Can only be called by the current owner.
*/
function transferOwnership(address newOwner) public virtual onlyOwner {
require(newOwner != address(0), "Ownable: new owner is the zero address");
_setOwner(newOwner);
}

function _setOwner(address newOwner) private {
address oldOwner = _owner;
_owner = newOwner;
emit OwnershipTransferred(oldOwner, newOwner);
}
}

// IUniswapV2Factory interface taken from: https://github.com/Uniswap/uniswap-v2-core/blob/master/contracts/interfaces/IUniswapV2Factory.sol
interface IUniswapV2Factory {
event PairCreated(address indexed token0, address indexed token1, address pair, uint);

function feeTo() external view returns (address);
function feeToSetter() external view returns (address);

function getPair(address tokenA, address tokenB) external view returns (address pair);
function allPairs(uint) external view returns (address pair);
function allPairsLength() external view returns (uint);

function createPair(address tokenA, address tokenB) external returns (address pair);

function setFeeTo(address) external;
function setFeeToSetter(address) external;
}

// IUniswapV2Pair interface taken from: https://github.com/Uniswap/uniswap-v2-core/blob/master/contracts/interfaces/IUniswapV2Pair.sol
interface IUniswapV2Pair {
event Approval(address indexed owner, address indexed spender, uint value);
event Transfer(address indexed from, address indexed to, uint value);

function name() external pure returns (string memory);
function symbol() external pure returns (string memory);
function decimals() external pure returns (uint8);
function totalSupply() external view returns (uint);
function balanceOf(address owner) external view returns (uint);
function allowance(address owner, address spender) external view returns (uint);

function approve(address spender, uint value) external returns (bool);
function transfer(address to, uint value) external returns (bool);
function transferFrom(address from, address to, uint value) external returns (bool);

function DOMAIN_SEPARATOR() external view returns (bytes32);
function PERMIT_TYPEHASH() external pure returns (bytes32);
function nonces(address owner) external view returns (uint);

function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external;

event Mint(address indexed sender, uint amount0, uint amount1);
event Burn(address indexed sender, uint amount0, uint amount1, address indexed to);
event Swap(
address indexed sender,
uint amount0In,
uint amount1In,
uint amount0Out,
uint amount1Out,
address indexed to
);
event Sync(uint112 reserve0, uint112 reserve1);

function MINIMUM_LIQUIDITY() external pure returns (uint);
function factory() external view returns (address);
function token0() external view returns (address);
function token1() external view returns (address);
function getReserves() external view returns (uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast);
function price0CumulativeLast() external view returns (uint);
function price1CumulativeLast() external view returns (uint);
function kLast() external view returns (uint);

function mint(address to) external returns (uint liquidity);
function burn(address to) external returns (uint amount0, uint amount1);
function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external;
function skim(address to) external;
function sync() external;

function initialize(address, address) external;
}

// IUniswapV2Router01 interface taken from: https://github.com/Uniswap/uniswap-v2-periphery/blob/master/contracts/interfaces/IUniswapV2Router01.sol
interface IUniswapV2Router01 {
function factory() external pure returns (address);
function WETH() external pure returns (address);

function addLiquidity(
address tokenA,
address tokenB,
uint amountADesired,
uint amountBDesired,
uint amountAMin,
uint amountBMin,
address to,
uint deadline
) external returns (uint amountA, uint amountB, uint liquidity);
function addLiquidityETH(
address token,
uint amountTokenDesired,
uint amountTokenMin,
uint amountETHMin,
address to,
uint deadline
) external payable returns (uint amountToken, uint amountETH, uint liquidity);
function removeLiquidity(
address tokenA,
address tokenB,
uint liquidity,
uint amountAMin,
uint amountBMin,
address to,
uint deadline
) external returns (uint amountA, uint amountB);
function removeLiquidityETH(
address token,
uint liquidity,
uint amountTokenMin,
uint amountETHMin,
address to,
uint deadline
) external returns (uint amountToken, uint amountETH);
function removeLiquidityWithPermit(
address tokenA,
address tokenB,
uint liquidity,
uint amountAMin,
uint amountBMin,
address to,
uint deadline,
bool approveMax, uint8 v, bytes32 r, bytes32 s
) external returns (uint amountA, uint amountB);
function removeLiquidityETHWithPermit(
address token,
uint liquidity,
uint amountTokenMin,
uint amountETHMin,
address to,
uint deadline,
bool approveMax, uint8 v, bytes32 r, bytes32 s
) external returns (uint amountToken, uint amountETH);
function swapExactTokensForTokens(
uint amountIn,
uint amountOutMin,
address[] calldata path,
address to,
uint deadline
) external returns (uint[] memory amounts);
function swapTokensForExactTokens(
uint amountOut,
uint amountInMax,
address[] calldata path,
address to,
uint deadline
) external returns (uint[] memory amounts);
function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline)
external
payable
returns (uint[] memory amounts);
function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline)
external
returns (uint[] memory amounts);
function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline)
external
returns (uint[] memory amounts);
function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline)
external
payable
returns (uint[] memory amounts);

function quote(uint amountA, uint reserveA, uint reserveB) external pure returns (uint amountB);
function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) external pure returns (uint amountOut);
function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) external pure returns (uint amountIn);
function getAmountsOut(uint amountIn, address[] calldata path) external view returns (uint[] memory amounts);
function getAmountsIn(uint amountOut, address[] calldata path) external view returns (uint[] memory amounts);
}

// IUniswapV2Router02 interface taken from: https://github.com/Uniswap/uniswap-v2-periphery/blob/master/contracts/interfaces/IUniswapV2Router02.sol
interface IUniswapV2Router02 is IUniswapV2Router01 {
function removeLiquidityETHSupportingFeeOnTransferTokens(
address token,
uint liquidity,
uint amountTokenMin,
uint amountETHMin,
address to,
uint deadline
) external returns (uint amountETH);
function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
address token,
uint liquidity,
uint amountTokenMin,
uint amountETHMin,
address to,
uint deadline,
bool approveMax, uint8 v, bytes32 r, bytes32 s
) external returns (uint amountETH);

function swapExactTokensForTokensSupportingFeeOnTransferTokens(
uint amountIn,
uint amountOutMin,
address[] calldata path,
address to,
uint deadline
) external;
function swapExactETHForTokensSupportingFeeOnTransferTokens(
uint amountOutMin,
address[] calldata path,
address to,
uint deadline
) external payable;
function swapExactTokensForETHSupportingFeeOnTransferTokens(
uint amountIn,
uint amountOutMin,
address[] calldata path,
address to,
uint deadline
) external;
}

/**
* @dev The official FAIRTREEToken smart contract
*/
contract FAIRTREEToken is Context, IERC20, Ownable {
using SafeMath for uint256;
using Address for address;

// General Info
string private _name = "FAIRTREE";
string private _symbol = "FAIRTREE";
uint8 private _decimals = 9;

// Liquidity Settings
IUniswapV2Router02 public _pancakeswapV2Router; // The address of the PancakeSwap V2 Router
address public _pancakeswapV2LiquidityPair; // The address of the PancakeSwap V2 liquidity pairing for FAIRTREE/WBNB

bool currentlySwapping;

modifier lockSwapping {
currentlySwapping = true;
_;
currentlySwapping = false;
}
event SwapAndLiquify(
uint256 tokensSwapped,
uint256 bnbReceived,
uint256 tokensIntoLiqudity
);

// Addresses
address payable public _marketingAddress = payable(0xDDb6Bd06dDEaB80CA0fb0259Cc8B09725249F255); // Marketing address used to pay for marketing
address payable public _burnAddress = payable(0x000000000000000000000000000000000000dEaD); // Burn address used to burn a portion of tokens

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

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

// Supply
uint256 private constant MAX = ~uint256(0);
uint256 private _tTotal = 1 * 10**15 * 10**9;
uint256 private _rTotal = (MAX - (MAX % _tTotal));
uint256 private _totalReflections; // Total reflections

// Token Tax Settings
uint256 public _taxFee = 7; // 7% tax
uint256 public _sellTaxFee = 14; // 14% tax
uint256 public _whaleSellTaxFee = 21; // 21% tax
uint256 private _previousTaxFee;

// Token Limits
uint256 public _maxTxAmount = 1 * 10**15 * 10**9; // 1 quadrillion
uint256 public _tokenSwapThreshold = 100 * 10**9 * 10**9; // 100 billion

// Timer Constants
uint private constant DAY = 86400; // How many seconds in a day

// Anti-Whale Settings
uint256 public _whaleSellThreshold = 500 * 10**9 * 10**9; // 500 billion
uint public _whaleSellTimer = DAY; // 24 hours
mapping (address => uint256) private _amountSold;
mapping (address => uint) private _timeSinceFirstSell;

// BUYBACK
bool public _enableBuyback = false; // Disabled on deployment
uint256 public _buybackBNBThreshold = 1 * 10**18; // 1 BNB will be required to be inside the contract before a buyback will be performed
uint256 public _buybackUpperLimit = 1 * 10**9 * 10**9; // 1 billion $FAIRTREE will be used to buy at maximum in any one trade
uint256 public _buybackBNBPercentage = 1; // 1% of BNB is used to buyback tokens

// LIQUIDITY
bool public _enableLiquidity = false; // Controls whether the contract will swap tokens

// LOTTERY
bool public _enableLottery = false; // Disabled on deployment
uint256 private _lotteryPool = 0; // How many reflections are in the lottery pool
uint public _lotteryChance = 25; // 1% chance to win on a buy
uint256 public _lotteryThreshold = 10 * 10**6 * 10**9; // 10 million tokens required to be in the pool before lottery can be triggered
uint256 public _lotteryMinimumSpend = 10 * 10**6 * 10**9; // 10 million tokens required to buy before before lottery can be triggered
address public _previousWinner;
uint256 public _previousWonAmount;
uint public _previousWinTime;
uint public _lastRoll;
uint256 private _nonce;

event LotteryAward(
address winner,
uint256 amount,
uint time
);

constructor () {
// Mint the total reflection balance to the deployer of this contract
_rOwned[_msgSender()] = _rTotal;

// Exclude the owner and the contract from paying fees
_isExcludedFromFees[owner()] = true;
_isExcludedFromFees[address(this)] = true;

// Set up the pancakeswap V2 router
IUniswapV2Router02 pancakeswapV2Router = IUniswapV2Router02(0x10ED43C718714eb63d5aA57B78B54704E256024E);
_pancakeswapV2LiquidityPair = IUniswapV2Factory(pancakeswapV2Router.factory())
.createPair(address(this), pancakeswapV2Router.WETH());
_pancakeswapV2Router = pancakeswapV2Router;

emit Transfer(address(0), _msgSender(), _tTotal);
}

/**
* @notice Required to recieve BNB from PancakeSwap V2 Router when swaping
*/
receive() external payable {}

/**
* @notice Withdraws BNB from the contract
*/
function withdrawBNB(uint256 amount) public onlyOwner() {
if(amount == 0) payable(owner()).transfer(address(this).balance);
else payable(owner()).transfer(amount);
}

/**
* @notice Withdraws non-FAIRTREE tokens that are stuck as to not interfere with the liquidity
*/
function withdrawForeignToken(address token) public onlyOwner() {
require(address(this) != address(token), "Cannot withdraw native token");
IERC20(address(token)).transfer(msg.sender, IERC20(token).balanceOf(address(this)));
}

/**
* @notice Transfers BNB to an address
*/
function transferBNBToAddress(address payable recipient, uint256 amount) private {
recipient.transfer(amount);
}

/**
* @notice Allows the contract to change the router, in the instance when PancakeSwap upgrades making the contract future proof
*/
function setRouterAddress(address router) public onlyOwner() {
// Connect to the new router
IUniswapV2Router02 newPancakeSwapRouter = IUniswapV2Router02(router);

// Grab an existing pair, or create one if it doesnt exist
address newPair = IUniswapV2Factory(newPancakeSwapRouter.factory()).getPair(address(this), newPancakeSwapRouter.WETH());
if(newPair == address(0)){
newPair = IUniswapV2Factory(newPancakeSwapRouter.factory()).createPair(address(this), newPancakeSwapRouter.WETH());
}
_pancakeswapV2LiquidityPair = newPair;

_pancakeswapV2Router = newPancakeSwapRouter;
}

function name() external view returns (string memory) {
return _name;
}

function symbol() external view returns (string memory) {
return _symbol;
}

function decimals() external view returns (uint8) {
return _decimals;
}

function totalSupply() external view override returns (uint256) {
return _tTotal;
}

function balanceOf(address account) public view override returns (uint256) {
if (_isExcluded[account]) return _tOwned[account];
return tokenFromReflection(_rOwned[account]);
}

function transfer(address recipient, uint256 amount) external override returns (bool) {
_transfer(_msgSender(), recipient, amount);
return true;
}

function allowance(address owner, address spender) external view override returns (uint256) {
return _allowances[owner][spender];
}

function approve(address spender, uint256 amount) external override returns (bool) {
_approve(_msgSender(), spender, amount);
return true;
}

function transferFrom(address sender, address recipient, uint256 amount) external override returns (bool) {
_transfer(sender, recipient, amount);
_approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, "ERC20: transfer amount exceeds allowance"));
return true;
}

function increaseAllowance(address spender, uint256 addedValue) external virtual returns (bool) {
_approve(_msgSender(), spender, _allowances[_msgSender()][spender].add(addedValue));
return true;
}

function decreaseAllowance(address spender, uint256 subtractedValue) external virtual returns (bool) {
_approve(_msgSender(), spender, _allowances[_msgSender()][spender].sub(subtractedValue, "ERC20: decreased allowance below zero"));
return true;
}

function _approve(address owner, address spender, uint256 amount) private {
require(owner != address(0), "ERC20: approve from the zero address");
require(spender != address(0), "ERC20: approve to the zero address");

_allowances[owner][spender] = amount;
emit Approval(owner, spender, amount);
}

function getTotalReflections() external view returns (uint256) {
return _totalReflections;
}

function isExcludedFromFee(address account) external view returns(bool) {
return _isExcludedFromFees[account];
}

function isExcludedFromReflection(address account) external view returns(bool) {
return _isExcluded[account];
}

function getLotteryTokens() public view returns (uint256) {
return tokenFromReflection(_lotteryPool);
}

function buybackUpperLimitAmount() external view returns (uint256) {
return _buybackUpperLimit;
}

function amountSold(address account) external view returns (uint256) {
return _amountSold[account];
}

function getTimeSinceFirstSell(address account) external view returns (uint) {
return _timeSinceFirstSell[account];
}

function excludeFromFee(address account) external onlyOwner() {
_isExcludedFromFees[account] = true;
}

function includeInFee(address account) external onlyOwner() {
_isExcludedFromFees[account] = false;
}

function setTaxFeePercent(uint256 taxFee) external onlyOwner() {
_taxFee = taxFee;
}

function setSellTaxFeePerecent(uint256 taxFee) external onlyOwner() {
_sellTaxFee = taxFee;
}

function setWhaleSellTaxFeePerecent(uint256 taxFee) external onlyOwner() {
_whaleSellTaxFee = taxFee;
}

function setMaxTxAmount(uint256 maxTxAmount) external onlyOwner() {
_maxTxAmount = maxTxAmount;
}

function setTokenSwapThreshold(uint256 tokenSwapThreshold) external onlyOwner() {
_tokenSwapThreshold = tokenSwapThreshold;
}

function setMarketingAddress(address marketingAddress) external onlyOwner() {
_marketingAddress = payable(marketingAddress);
}

function setBuyback(bool b) external onlyOwner() {
_enableBuyback = b;
}

function setBuybackBNBThreshold(uint256 bnbAmount) external onlyOwner() {
_buybackBNBThreshold = bnbAmount;
}

function setBuybackUpperLimit(uint256 buybackLimit) external onlyOwner() {
_buybackUpperLimit = buybackLimit;
}

function setBuybackBNBPercentage(uint256 percentage) external onlyOwner() {
_buybackBNBPercentage = percentage;
}

function setLiquidity(bool b) external onlyOwner() {
_enableLiquidity = b;
}

function setWhaleSellThreshold(uint256 amount) external onlyOwner() {
_whaleSellThreshold = amount;
}

function setWhaleSellTimer(uint time) external onlyOwner() {
_whaleSellTimer = time;
}

function setLottery(bool b) external onlyOwner() {
_enableLottery = b;
}

function setLotteryChance(uint chance) external onlyOwner() {
_lotteryChance = chance;
}

function setLotteryThreshold(uint256 threshold) external onlyOwner() {
_lotteryThreshold = threshold;
}

function setLotteryMinimumSpend(uint256 minimumSpend) external onlyOwner() {
_lotteryMinimumSpend = minimumSpend;
}

/**
* @notice Converts a token value to a reflection value
*/
function reflectionFromToken(uint256 tAmount, bool deductTransferFee) public view returns(uint256) {
require(tAmount <= _tTotal, "Amount must be less than supply");
if (!deductTransferFee) {
(uint256 rAmount,,,,) = _getValues(tAmount);
return rAmount;
} else {
(,uint256 rTransferAmount,,,) = _getValues(tAmount);
return rTransferAmount;
}
}

/**
* @notice Converts a reflection value to a token value
*/
function tokenFromReflection(uint256 rAmount) public view returns(uint256) {
require(rAmount <= _rTotal, "Amount must be less than total reflections");
uint256 currentRate = _getRate();
return rAmount.div(currentRate);
}

/**
* @notice Generates a random number between 1 and 1000
*/
function random() private returns (uint) {
uint r = uint(uint256(keccak256(abi.encodePacked(block.difficulty, block.timestamp, _nonce))) % 1000);
r = r.add(1);
_nonce ;
return r;
}

/**
* @notice Removes all fees and stores their previous values to be later restored
*/
function removeAllFees() private {
if(_taxFee == 0) return;

_previousTaxFee = _taxFee;
_taxFee = 0;
}

/**
* @notice Restores the fees
*/
function restoreAllFees() private {
_taxFee = _previousTaxFee;
}

/**
* @notice Calculates whether the lottery is hit using a random number
*/
function calculateLotteryReward() private returns (uint256) {
// If the transfer is a buy, and the lottery pool is above a certain token threshold, start to award it
uint256 reward = 0;
uint256 lotteryTokens = getLotteryTokens();
if (lotteryTokens >= _lotteryThreshold) {
// Generates a random number between 1 and 1000
_lastRoll = random();
if(_lastRoll <= _lotteryChance) {
reward = lotteryTokens;
}
}
return reward;
}

/**
* @notice Collects all the necessary transfer values
*/
function _getValues(uint256 tAmount) private view returns (uint256, uint256, uint256, uint256, uint256) {
(uint256 tTransferAmount, uint256 tFee) = _getTValues(tAmount);
(uint256 rAmount, uint256 rTransferAmount, uint256 rFee) = _getRValues(tAmount, tFee, _getRate());
return (rAmount, rTransferAmount, rFee, tTransferAmount, tFee);
}

/**
* @notice Calculates transfer token values
*/
function _getTValues(uint256 tAmount) private view returns (uint256, uint256) {
uint256 tFee = tAmount.mul(_taxFee).div(100);
uint256 tTransferAmount = tAmount.sub(tFee);
return (tTransferAmount, tFee);
}

/**
* @notice Calculates transfer reflection values
*/
function _getRValues(uint256 tAmount, uint256 tFee, uint256 currentRate) private pure returns (uint256, uint256, uint256) {
uint256 rAmount = tAmount.mul(currentRate);
uint256 rFee = tFee.mul(currentRate);
uint256 rTransferAmount = rAmount.sub(rFee);
return (rAmount, rTransferAmount, rFee);
}

/**
* @notice Calculates the rate of reflections to tokens
*/
function _getRate() private view returns(uint256) {
(uint256 rSupply, uint256 tSupply) = _getCurrentSupply();
return rSupply.div(tSupply);
}

/**
* @notice Gets the current supply values
*/
function _getCurrentSupply() private view returns(uint256, uint256) {
uint256 rSupply = _rTotal;
uint256 tSupply = _tTotal;
for (uint256 i = 0; i < _excluded.length; i ) {
if (_rOwned[_excluded[i]] > rSupply || _tOwned[_excluded[i]] > tSupply) return (_rTotal, _tTotal);
rSupply = rSupply.sub(_rOwned[_excluded[i]]);
tSupply = tSupply.sub(_tOwned[_excluded[i]]);
}
if (rSupply < _rTotal.div(_tTotal)) return (_rTotal, _tTotal);
return (rSupply, tSupply);
}

/**
* @notice Excludes an address from receiving reflections
*/
function excludeFromReward(address account) external onlyOwner() {
require(!_isExcluded[account], "Account is already excluded");
if(_rOwned[account] > 0) {
_tOwned[account] = tokenFromReflection(_rOwned[account]);
}
_isExcluded[account] = true;
_excluded.push(account);
}

/**
* @notice Includes an address back into the reflection system
*/
function includeInReward(address account) external onlyOwner() {
require(_isExcluded[account], "Account is already included");
for (uint256 i = 0; i < _excluded.length; i ) {
if (_excluded[i] == account) {
_excluded[i] = _excluded[_excluded.length - 1];
_tOwned[account] = 0;
_isExcluded[account] = false;
_excluded.pop();
break;
}
}
}

/**
* @notice Transfers a winner an extra amount of tokens
*/
function _lotteryTransfer(address winner, uint256 tAmount) private {
if (_isExcluded[winner]) {
_tOwned[winner] = _tOwned[winner].add(tAmount);
}
_rOwned[winner] = _rOwned[winner].add(_lotteryPool);
_lotteryPool = 0;
_previousWinner = winner;
_previousWonAmount = tAmount;
_previousWinTime = block.timestamp;
emit LotteryAward(winner, tAmount, block.timestamp);
emit Transfer(address(this), winner, tAmount);
}

/**
* @notice Handles the before and after of a token transfer, such as taking fees and firing off a swap and liquify event
*/
function _transfer(address from, address to, uint256 amount) private {
require(from != address(0), "ERC20: transfer from the zero address");
require(to != address(0), "ERC20: transfer to the zero address");
require(amount > 0, "Transfer amount must be greater than zero");

// Only the owner of this contract can bypass the max transfer amount
if(from != owner() && to != owner()) {
require(amount <= _maxTxAmount, "Transfer amount exceeds the maxTxAmount.");
}

// LOTTERY MECHANISM
// If the transaction is a buy, then we roll to see if we award any extra tokens
if(_enableLottery && amount >= _lotteryMinimumSpend && from == _pancakeswapV2LiquidityPair) {
uint256 lotteryReward = calculateLotteryReward();
if (lotteryReward > 0) {
_lotteryTransfer(to, lotteryReward);
}
}

// Gets the contracts FAIRTREE balance for buybacks, charity, liquidity and marketing
uint256 tokenBalance = balanceOf(address(this));
if(tokenBalance >= _maxTxAmount)
{
tokenBalance = _maxTxAmount;
}

// AUTO-LIQUIDITY MECHANISM
// Check that the contract balance has reached the threshold required to execute a swap and liquify event
// Do not execute the swap and liquify if there is already a swap happening
// Do not allow the adding of liquidity if the sender is the PancakeSwap V2 liquidity pool
if (_enableLiquidity && tokenBalance >= _tokenSwapThreshold && !currentlySwapping && from != _pancakeswapV2LiquidityPair) {
tokenBalance = _tokenSwapThreshold;
swapAndLiquify(tokenBalance);
}

// BUYBACK MECHANISM
// If buyback is enabled, and someone is sending tokens to the liquidity pool (i.e. a sell), then we buy back tokens.
// Do not execute the buyback if there is already a swap happening
if (_enableBuyback && !currentlySwapping && to == _pancakeswapV2LiquidityPair) {
uint256 balance = address(this).balance;

// Only execute a buyback when the contract has more than 1.0 BNB
if (balance > _buybackBNBThreshold) {
if (balance >= _buybackUpperLimit) {
balance = _buybackUpperLimit;
}

// Buy back tokens with 1% of the BNB inside the contract
buyBackTokens(balance.mul(_buybackBNBPercentage).div(100));
}
}

// If any account belongs to _isExcludedFromFee account then remove the fee
bool takeFee = !(_isExcludedFromFees[from] || _isExcludedFromFees[to]);

// ANTI-WHALE TAX MECHANISM
// If we are taking fees and sending tokens to the liquidity pool (i.e. a sell), check for anti-whale tax
if (takeFee && to == _pancakeswapV2LiquidityPair) {

// We will assume that the normal sell tax rate will apply
uint256 fee = _sellTaxFee;

// Get the time difference in seconds between now and the first sell
uint delta = block.timestamp.sub(_timeSinceFirstSell[from]);

// Get the new total to see if it has spilled over the threshold
uint256 newTotal = _amountSold[from].add(amount);

// If a known wallet started their selling within the whale sell timer window, check if they're trying to spill over the threshold
// If they are then increase the tax amount
if (delta > 0 && delta < _whaleSellTimer && _timeSinceFirstSell[from] != 0) {
if (newTotal > _whaleSellThreshold) {
fee = _whaleSellTaxFee;
}
_amountSold[from] = newTotal;
} else if (_timeSinceFirstSell[from] == 0 && newTotal > _whaleSellThreshold) {
fee = _whaleSellTaxFee;
_amountSold[from] = newTotal;
} else {
// Otherwise we reset their sold amount and timer
_timeSinceFirstSell[from] = block.timestamp;
_amountSold[from] = amount;
}

// Set the tax rate to the sell tax rate, if the whale sell tax rate applies then we set that
_previousTaxFee = _taxFee;
_taxFee = fee;
}

// Remove fees completely from the transfer if either wallet are excluded
if (!takeFee) {
removeAllFees();
}

// Transfer the token amount from sender to receipient.
_tokenTransfer(from, to, amount);

// If we removed the fees for this transaction, then restore them for future transactions
if (!takeFee) {
restoreAllFees();
}

// If this transaction was a sell, and we took a fee, restore the fee amount back to the original buy amount
if (takeFee && to == _pancakeswapV2LiquidityPair) {
_taxFee = _previousTaxFee;
}

}

/**
* @notice Handles the actual token transfer
*/
function _tokenTransfer(address sender, address recipient, uint256 tAmount) private {
// Calculate the values required to execute a transfer
(uint256 tTransferAmount, uint256 tFee) = _getTValues(tAmount);
(uint256 rAmount, uint256 rTransferAmount,) = _getRValues(tAmount, tFee, _getRate());

// Transfer from sender to recipient
if (_isExcluded[sender]) {
_tOwned[sender] = _tOwned[sender].sub(tAmount);
}
_rOwned[sender] = _rOwned[sender].sub(rAmount);

if (_isExcluded[recipient]) {
_tOwned[recipient] = _tOwned[recipient].add(tTransferAmount);
}
_rOwned[recipient] = _rOwned[recipient].add(rTransferAmount);

// This is always 1% of a transaction worth of tokens
if (tFee > 0) {
uint256 tPortion = tFee.div(_taxFee);

// Burn some of the taxed tokens
_burnTokens(tPortion);

// Reflect some of the taxed tokens
_reflectTokens(tPortion);

// Take the rest of the taxed tokens for the other functions
_takeTokens(tFee.sub(tPortion).sub(tPortion).sub(tPortion), tPortion);
}

// Emit an event
emit Transfer(sender, recipient, tTransferAmount);
}

/**
* @notice Burns FAIRTREE tokens straight to the burn address
*/
function _burnTokens(uint256 tFee) private {
uint256 rFee = tFee.mul(_getRate());
_rOwned[_burnAddress] = _rOwned[_burnAddress].add(rFee);
if(_isExcluded[_burnAddress]) {
_tOwned[_burnAddress] = _tOwned[_burnAddress].add(tFee);
}
}

/**
* @notice Increases the rate of how many reflections each token is worth
*/
function _reflectTokens(uint256 tFee) private {
uint256 rFee = tFee.mul(_getRate());
_rTotal = _rTotal.sub(rFee);
_totalReflections = _totalReflections.add(tFee);
}

/**
* @notice The contract takes a portion of tokens from taxed transactions
*/
function _takeTokens(uint256 tTakeAmount, uint256 tLottery) private {
uint256 currentRate = _getRate();
uint256 rTakeAmount = tTakeAmount.mul(currentRate);
_rOwned[address(this)] = _rOwned[address(this)].add(rTakeAmount);
if(_isExcluded[address(this)]) {
_tOwned[address(this)] = _tOwned[address(this)].add(tTakeAmount);
}

// Add a portion to the lottery pool to be rewarded to a lucky buyer
uint256 rLottery = tLottery.mul(currentRate);
_lotteryPool = _lotteryPool.add(rLottery);
}

/**
* @notice Buys tokens using the contract balance
*/
function buyBackTokens(uint256 amount) private lockSwapping {
if (amount > 0) {
swapBNBForTokens(amount);
}
}

/**
* @notice Generates BNB by selling tokens and pairs some of the received BNB with tokens to add and grow the liquidity pool
*/
function swapAndLiquify(uint256 tokenAmount) private lockSwapping {
// Split the contract balance into the swap portion and the liquidity portion
uint256 eigth = tokenAmount.div(8); // 1/8 of the tokens, used for liquidity
uint256 swapAmount = tokenAmount.sub(eigth); // 7/8 of the tokens, used to swap for BNB

// Capture the contract's current BNB balance so that we know exactly the amount of BNB that the
// swap creates. This way the liquidity event wont include any BNB that has been collected by other means.
uint256 initialBalance = address(this).balance;

// Swap 7/8ths of FAIRTREE tokens for BNB
swapTokensForBNB(swapAmount);

// How much BNB did we just receive
uint256 receivedBNB = address(this).balance.sub(initialBalance);

// A seventh of the received BNB will be paired with the eigth of tokens left behind
uint256 liquidityBNB = receivedBNB.div(7);

// Add liquidity via the PancakeSwap V2 Router
addLiquidity(eigth, liquidityBNB);

// We now have 6/7ths left of BNB (converted from FAIRTREE)
// We want to send 4/7ths to the marketing wallet and keep 2/7ths within the contract for buyback
uint256 marketingBNB = receivedBNB.div(7).mul(4);

// Send the remaining BNB to the marketing wallet
transferBNBToAddress(_marketingAddress, marketingBNB);

emit SwapAndLiquify(swapAmount, liquidityBNB, eigth);
}

/**
* @notice Swap tokens for BNB storing the resulting BNB in the contract
*/
function swapTokensForBNB(uint256 tokenAmount) private {
// Generate the Pancakeswap pair for DHT/WBNB
address[] memory path = new address[](2);
path[0] = address(this);
path[1] = _pancakeswapV2Router.WETH(); // WETH = WBNB on BSC

_approve(address(this), address(_pancakeswapV2Router), tokenAmount);

// Execute the swap
_pancakeswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(
tokenAmount,
0, // Accept any amount of BNB
path,
address(this),
block.timestamp.add(300)
);
}

/**
* @notice Swaps BNB for tokens and immedietely burns them
*/
function swapBNBForTokens(uint256 amount) private {
// generate the uniswap pair path of token -> weth
address[] memory path = new address[](2);
path[0] = _pancakeswapV2Router.WETH();
path[1] = address(this);

_pancakeswapV2Router.swapExactETHForTokensSupportingFeeOnTransferTokens{value: amount}(
0, // Accept any amount of FAIRTREE
path,
_burnAddress, // Burn address
block.timestamp.add(300)
);
}

/**
* @notice Adds liquidity to the PancakeSwap V2 LP
*/
function addLiquidity(uint256 tokenAmount, uint256 bnbAmount) private {
// Approve token transfer to cover all possible scenarios
_approve(address(this), address(_pancakeswapV2Router), tokenAmount);

// Adds the liquidity and gives the LP tokens to the owner of this contract
// The LP tokens need to be manually locked
_pancakeswapV2Router.addLiquidityETH{value: bnbAmount}(
address(this),
tokenAmount,
0, // Take any amount of tokens (ratio varies)
0, // Take any amount of BNB (ratio varies)
owner(),
block.timestamp.add(300)
);
}

/**
* @notice Allows a user to voluntarily reflect their tokens to everyone else
*/
function reflect(uint256 tAmount) public {
require(!_isExcluded[_msgSender()], "Excluded addresses cannot call this function");
(uint256 rAmount,,,,) = _getValues(tAmount);
_rOwned[_msgSender()] = _rOwned[_msgSender()].sub(rAmount);
_rTotal = _rTotal.sub(rAmount);
_totalReflections = _totalReflections.add(tAmount);
}
}