pragma solidity 0.8.0;

pragma solidity 0.8.0;
// SPDX-License-Identifier: Unlicensed

/*
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes calldata) {
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
        return msg.data;
    }
}

interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);

    /**
     * @dev Moves `amount` tokens from the caller's account to `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);

    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);

    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
}

/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
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 () {
        address msgSender = _msgSender();
        _owner = msgSender;
        emit OwnershipTransferred(address(0), 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 {
        emit OwnershipTransferred(_owner, address(0));
        _owner = 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");
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }
}

/**
 * @dev Wrappers over Solidity's arithmetic operations.
 *
 * NOTE: `SafeMath` is no longer needed starting with Solidity 0.8. The compiler
 * now has built in overflow checking.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            uint256 c = a + b;
            if (c < a) return (false, 0);
            return (true, c);
        }
    }

    /**
     * @dev Returns the substraction of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b > a) return (false, 0);
            return (true, a - b);
        }
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
            // benefit is lost if 'b' is also tested.
            // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
            if (a == 0) return (true, 0);
            uint256 c = a * b;
            if (c / a != b) return (false, 0);
            return (true, c);
        }
    }

    /**
     * @dev Returns the division of two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a / b);
        }
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a % b);
        }
    }

    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        return a + b;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        return a - b;
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        return a * b;
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator.
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return a / b;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        return a % b;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {trySub}.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        unchecked {
            require(b <= a, errorMessage);
            return a - b;
        }
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        unchecked {
            require(b > 0, errorMessage);
            return a / b;
        }
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting with custom message when dividing by zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryMod}.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        unchecked {
            require(b > 0, errorMessage);
            return a % b;
        }
    }
}



/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     */
    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;
        // solhint-disable-next-line no-inline-assembly
        assembly { size := extcodesize(account) }
        return size > 0;
    }

    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");

        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
        (bool success, ) = recipient.call{ value: amount }("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }

    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain`call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
      return functionCall(target, data, "Address: low-level call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    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");
    }

    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    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");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.call{ value: value }(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {
        require(isContract(target), "Address: static call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.staticcall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
        require(isContract(target), "Address: delegate call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (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

                // solhint-disable-next-line no-inline-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}


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);
}


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;
}


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;
}


contract BananaToken is Context, Ownable, IERC20 {

    // Libraries
	using SafeMath for uint256;
    using Address for address;
    
    // Attributes for ERC-20 token
    string private _name = "Island";
    string private _symbol = "ISLE";
    uint8 private _decimals = 9;
    
    mapping (address => uint256) private _balance;
    mapping (address => mapping (address => uint256)) private _allowances;
    
    uint256 private _total = 690000000 * 10**6 * 10**9;
    uint256 private maxTxAmount = 3450000 * 10**6 * 10**9;
    uint256 private numTokensSellToAddToLiquidity = 345000 * 10**6 * 10**9;
    uint256 private minHoldingThreshold = 100 * 10**6 * 10**9;
    
    // Island attributes
    uint8 public sandTax = 5;
    uint8 public burnableFundRate = 5;
    uint8 public operationalFundRate = 1;
    
    uint256 public sandFund;
    uint256 public burnableFund;
    uint256 public operationalFund;
    
    bool inSwapAndLiquify;
    bool public swapAndLiquifyEnabled = true;

    IUniswapV2Router02 public immutable uniSwapV2Router;
    address public immutable uniswapV2Pair;

	struct Entity {
		address _key;
		bool _isValid;
		uint256 _lastRewardedEventTimeStamp;
		uint256 _createdAt;
	}
	mapping (address => uint256) private addressToIndex;
	mapping (uint256 => Entity) private indexToEntity;
	uint256 private lastIndexUsed = 0;
	uint256 private lastEntryAllowed = 0;
	
	uint32 public perBatchSize = 100;
	
	event GrandPrizeReceivedAddresses (
    	address addressReceived,
    	uint256 amount
    );

    event MediumPrizeReceivedAddresses (
    	address[] addressesReceived,
    	uint256 amount
    );
    
    event SmallPrizePayoutComplete (
    	uint256 amount
    );
    
    event SwapAndLiquifyEnabledUpdated(bool enabled);
    event SwapAndLiquify(
        uint256 tokensSwapped,
        uint256 ethReceived,
        uint256 tokensIntoLiqudity
    );
    
    event MinEligibilityUpdated(
        uint256 amount
    );
    
    event OperationalFundWithdrawn(
        uint256 amount,
        address recepient,
        string reason
    );

    constructor () {
	    _balance[_msgSender()] = _total;
	    addEntity(_msgSender());
	    
	    sandFund = 0;
        burnableFund = 0;
        operationalFund = 0;
        inSwapAndLiquify = false;
	    
	    IUniswapV2Router02 _UniSwapV2Router = IUniswapV2Router02(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D);
        uniswapV2Pair = IUniswapV2Factory(_UniSwapV2Router.factory())
            .createPair(address(this), _UniSwapV2Router.WETH());
            
        uniSwapV2Router = _UniSwapV2Router;
        
        emit Transfer(address(0), _msgSender(), _total);
    }
    
    modifier lockTheSwap {
        inSwapAndLiquify = true;
        _;
        inSwapAndLiquify = false;
    }
    
    // --- section 1 --- : Standard ERC 20 functions

    function name() public view returns (string memory) {
        return _name;
    }

    function symbol() public view returns (string memory) {
        return _symbol;
    }

    function decimals() public view returns (uint8) {
        return _decimals;
    }
    
    function totalSupply() public view override returns (uint256) {
        return _total;
    }

    function balanceOf(address account) public view override returns (uint256) {
        return _balance[account];
    }
    
    function approve(address spender, uint256 amount) public override returns (bool) {
        _approve(_msgSender(), spender, amount);
        return true;
    }
    
    function transfer(address recipient, uint256 amount) public override returns (bool) {
        _transfer(_msgSender(), recipient, amount);
        return true;
    }

    function transferFrom(address sender, address recipient, uint256 amount) public override returns (bool) {
        _transfer(sender, recipient, amount);
        _approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, "ERC20: transfer amount exceeds allowance"));
        return true;
    }

    function allowance(address owner, address spender) public view override returns (uint256) {
        return _allowances[owner][spender];
    }

    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].add(addedValue));
        return true;
    }

    function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].sub(subtractedValue, "ERC20: decreased allowance below zero"));
        return true;
    }
    
    // --- section 2 --- : Island specific logics
    
    function burnToken(uint256 amount) public onlyOwner() virtual {
        require(amount <= _balance[address(this)], "Cannot burn more than avilable balancec");
        require(amount <= burnableFund, "Cannot burn more than burn fund");

        _balance[address(this)] = _balance[address(this)].sub(amount);
        _total = _total.sub(amount);
        burnableFund = burnableFund.sub(amount);

        emit Transfer(address(this), address(0), burnableFund);
    }
    
    function getCommunityIslandFund() public view returns (uint256) {
    	uint256 communityFund = burnableFund.add(sandFund).add(operationalFund);
    	return communityFund;
    }
    
    function getminHoldingThreshold() public view returns (uint256) {
        return minHoldingThreshold;
    }
    
    function getMaxTxnAmount() public view returns (uint256) {
        return maxTxAmount;
    }

    function setSwapAndLiquifyEnabled(bool _enabled) public onlyOwner() {
    	swapAndLiquifyEnabled = _enabled;
        emit SwapAndLiquifyEnabledUpdated(_enabled);
    }
    
    function setminHoldingThreshold(uint256 amount) public onlyOwner() {
        minHoldingThreshold = amount;
        emit MinEligibilityUpdated(amount);
    }
    
    function setMaxTxnAmount(uint256 amount) public onlyOwner() {
        maxTxAmount = amount;
    }
    
    function setBatchSize(uint32 newSize) public onlyOwner() {
        perBatchSize = newSize;
    }

    function withdrawOperationFund(uint256 amount, address walletAddress, string memory reason) public onlyOwner() {
        require(amount < operationalFund, "You cannot withdraw more funds that you have in island fund");
    	require(amount <= _balance[address(this)], "You cannot withdraw more funds that you have in operation fund");
    	
    	// track operation fund after withdrawal
    	operationalFund = operationalFund.sub(amount);
    	_balance[address(this)] = _balance[address(this)].sub(amount);
    	_balance[walletAddress] = _balance[walletAddress].add(amount);
    	
    	emit OperationalFundWithdrawn(amount, walletAddress, reason);
    }
    
    function swapAndLiquify(uint256 contractTokenBalance) private lockTheSwap {
        uint256 half = contractTokenBalance.div(2);
        uint256 otherHalf = contractTokenBalance.sub(half);

        uint256 initialBalance = address(this).balance;
        swapTokensForEth(half);
        uint256 newBalance = address(this).balance.sub(initialBalance);

        addLiquidity(otherHalf, newBalance);
        
        emit SwapAndLiquify(half, newBalance, otherHalf);
    }

    function swapTokensForEth(uint256 tokenAmount) private {
        address[] memory path = new address[](2);
        path[0] = address(this);
        path[1] = uniSwapV2Router.WETH();

        _approve(address(this), address(uniSwapV2Router), tokenAmount);

        // make the swap
        uniSwapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(
            tokenAmount,
            0, // accept any amount of ETH
            path,
            address(this),
            block.timestamp
        );
    }

    //to recieve WETH from Uniswap when swaping
    receive() external payable {}

    function addLiquidity(uint256 tokenAmount, uint256 ethAmount) private {
        // approve token transfer to cover all possible scenarios
        _approve(address(this), address(uniSwapV2Router), tokenAmount);

        // add the liquidity
        uniSwapV2Router.addLiquidityETH{value: ethAmount}(
            address(this),
            tokenAmount,
            0, // slippage is unavoidable
            0, // slippage is unavoidable
            owner(),
            block.timestamp
        );
    }
    
    // --- section 3 --- : Executions
    
    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 _transfer(address fromAddress, address toAddress, uint256 amount) private {
        require(fromAddress != address(0), "ERC20: transfer from the zero address");
        require(toAddress != address(0), "ERC20: transfer to the zero address");
        require(amount > 0, "Transfer amount must be greater than zero");
        if(fromAddress != owner() && toAddress != owner())
            require(amount <= maxTxAmount, "Transfer amount exceeds the maxTxAmount.");
        require(amount <= _balance[fromAddress], "Transfer amount exceeds the balance.");

        // This is contract's balance without any reserved funds such as island Fund
        uint256 contractTokenBalance = balanceOf(address(this)).sub(getCommunityIslandFund());
        bool overMinTokenBalance = contractTokenBalance >= numTokensSellToAddToLiquidity;
        
        // Dynamically hydrate LP. Standard practice in recent altcoin
        if (
            overMinTokenBalance &&
            !inSwapAndLiquify &&
            fromAddress != uniswapV2Pair &&
            swapAndLiquifyEnabled
        ) {
            contractTokenBalance = numTokensSellToAddToLiquidity;
            swapAndLiquify(contractTokenBalance);
        }
        
        _balance[fromAddress] = _balance[fromAddress].sub(amount);
        uint256 transactionTokenAmount = _getValues(amount);
        _balance[toAddress] = _balance[toAddress].add(transactionTokenAmount);

        // Add and remove wallet address from SAND eligibility
        if (_balance[toAddress] >= minHoldingThreshold && toAddress != address(this)){
        	addEntity(toAddress);
        }
        if (_balance[fromAddress] < minHoldingThreshold && fromAddress != address(this)) {
        	removeEntity(fromAddress);
        }
        
        shuffleEntities(amount, transactionTokenAmount);

        emit Transfer(fromAddress, toAddress, transactionTokenAmount);
    }

    function _getValues(uint256 amount) private returns (uint256) {
    	uint256 sandTaxFee = _extractSandFund(amount);
        uint256 operationalTax = _extractOperationalFund(amount);
    	uint256 burnableFundTax = _extractBurnableFund(amount);

    	uint256 businessTax = operationalTax.add(burnableFundTax).add(sandTaxFee);
    	uint256 transactionAmount = amount.sub(businessTax);

		return transactionAmount;
    }

    function _extractSandFund(uint256 amount) private returns (uint256) {
    	uint256 sandFundContribution = _getExtractableFund(amount, sandTax);
    	// Track of sandContribution
    	sandFund = sandFund.add(sandFundContribution);
    	_balance[address(this)] = _balance[address(this)].add(sandFundContribution);
    	
    	return sandFundContribution;
    }

    function _extractOperationalFund(uint256 amount) private returns (uint256) {
        
        (uint256 operationalFundContribution) = _getExtractableFund(amount, operationalFundRate);
    	
    	operationalFund = operationalFund.add(operationalFundContribution);
    	_balance[address(this)] = _balance[address(this)].add(operationalFundContribution);

    	return operationalFundContribution;
    }

    function _extractBurnableFund(uint256 amount) private returns (uint256) {
    	(uint256 burnableFundContribution) = _getExtractableFund(amount, burnableFundRate);
    	burnableFund = burnableFund.add(burnableFundContribution);
    	_balance[address(this)] = _balance[address(this)].add(burnableFundContribution);
    	return burnableFundContribution;
    }

    function _getExtractableFund(uint256 amount, uint8 rate) private pure returns (uint256) {
    	return amount.mul(rate).div(10**2);
    }
    
    // --- Section 4 --- : SAND functions. 
    // Off-chain bot calls payoutLargeRedistribution, payoutMediumRedistribution, payoutSmallRedistribution in order
    
    function payoutLargeRedistribution(uint256 eventTimeStamp) public onlyOwner() returns (bool success) {
        uint256 seed = 69;
        uint256 largePrize = sandFund.div(4);
        uint randNum = uint(keccak256(abi.encodePacked(block.timestamp, msg.sender, seed))) % lastIndexUsed;
        
        Entity memory bigPrizeEligibleEntity = getEntity(randNum, false);
        while (bigPrizeEligibleEntity._isValid != true) {
            randNum = uint(keccak256(abi.encodePacked(block.timestamp, msg.sender, seed))) % lastIndexUsed;
            bigPrizeEligibleEntity = getEntity(randNum, false);
        }
        
        address bigPrizeEligibleAddress = bigPrizeEligibleEntity._key;
        
        sandFund = sandFund.sub(largePrize);
        _balance[bigPrizeEligibleAddress] = _balance[bigPrizeEligibleAddress].add(sandFund);
        _balance[address(this)] = _balance[address(this)].sub(largePrize);
        indexToEntity[addressToIndex[bigPrizeEligibleAddress]]._lastRewardedEventTimeStamp = eventTimeStamp;
        
        emit GrandPrizeReceivedAddresses(bigPrizeEligibleAddress, largePrize);
        
        return true;
    }
    
    function payoutMediumRedistribution(uint256 eventTimeStamp) public onlyOwner() returns (bool success) {
        // Should be executed after grand prize is received
        uint256 mediumPrize = sandFund.div(3).mul(2);
        uint256 eligibleHolderCount = 100;
        uint256 totalDisbursed = 0;
        uint256 seed = 69;
        address[] memory eligibleAddresses = new address[](100);
        uint8 counter = 0;
        
        // Not likely scenarios where there are less than 100 eligible accounts
        if (getEntityListLength() <= 100) {
            //  If eligible acccount counts are less than 100, evenly split
    		eligibleHolderCount = getEntityListLength();
    		mediumPrize = mediumPrize.div(eligibleHolderCount);
    		while (counter < eligibleHolderCount) {
    	    
        	    if (indexToEntity[counter + 1]._isValid) {
        	        eligibleAddresses[counter] = indexToEntity[counter + 1]._key;
        	        totalDisbursed = totalDisbursed.add(mediumPrize);
        	        _balance[indexToEntity[counter + 1]._key] = _balance[indexToEntity[counter + 1]._key].add(mediumPrize);
        	        indexToEntity[counter + 1]._lastRewardedEventTimeStamp = eventTimeStamp;
        	        counter++;
        	    }
        	    seed = seed.add(1);
        	}
        	
        	sandFund = sandFund.sub(totalDisbursed);
        	_balance[address(this)] = _balance[address(this)].sub(totalDisbursed);
        	
        	emit MediumPrizeReceivedAddresses(eligibleAddresses, mediumPrize);
        	
        	return true;
    	}
    	
    	mediumPrize = mediumPrize.div(eligibleHolderCount);
    	
    	// Max iteration should never be comparably larger than 100
    	while (counter < eligibleHolderCount) {
    	    uint randNum = uint(keccak256(abi.encodePacked(block.timestamp, msg.sender, seed))) % lastIndexUsed;
    	    
    	    if (indexToEntity[randNum]._isValid) {
    	        eligibleAddresses[counter] = indexToEntity[randNum]._key;
    	        totalDisbursed = totalDisbursed.add(mediumPrize);
    	        _balance[indexToEntity[randNum]._key] = _balance[indexToEntity[randNum]._key].add(mediumPrize);
    	        indexToEntity[randNum]._lastRewardedEventTimeStamp = eventTimeStamp;
    	        counter++;
    	    }
    	    seed = seed.add(1);
    	}
    	
    	sandFund = sandFund.sub(totalDisbursed);
        _balance[address(this)] = _balance[address(this)].sub(totalDisbursed);
    	
    	emit MediumPrizeReceivedAddresses(eligibleAddresses, mediumPrize);
		
		return true;
    }
    
    function payoutSmallRedistribution(uint256 startIndex, uint256 rewardAmount, uint256 eventTimeStamp) public onlyOwner() returns (bool success) {
        require (startIndex > 0, "Index for this cannot be 0");
        uint256 totalDisbursed = 0;
        
        for (uint256 i = startIndex; i < startIndex + perBatchSize; i++) {
            if  (sandFund < rewardAmount) {
                break;
            }
            // Timestamp being used to prevent duplicate rewards
            if (indexToEntity[i]._isValid == true && indexToEntity[i]._lastRewardedEventTimeStamp < eventTimeStamp) {
                _balance[indexToEntity[i]._key] = _balance[indexToEntity[i]._key].add(rewardAmount);
                totalDisbursed = totalDisbursed.add(rewardAmount);
                indexToEntity[i]._lastRewardedEventTimeStamp = eventTimeStamp;
            }
            if (i == lastIndexUsed) {
                emit SmallPrizePayoutComplete(rewardAmount);
                break;
            }
        }
        
        sandFund = sandFund.sub(totalDisbursed);
        _balance[address(this)] = _balance[address(this)].sub(totalDisbursed);
        
        return true;
    }
    
    function getUnrewardedAddressCountAndPrizeAmount() public view returns (uint256, uint256) {
        uint256 eligibleCount = getEntityListLength();
        return (eligibleCount, sandFund.div(eligibleCount));
    }
    
    // --- Section 5 ---

    function addEntity (address walletAddress) private {
        if (addressToIndex[walletAddress] != 0) {
            return;
        }
        uint256 index = lastIndexUsed.add(1);
        
		indexToEntity[index] = Entity({
		    _key: walletAddress,
		    _isValid: true, 
		    _lastRewardedEventTimeStamp: block.timestamp, 
		    _createdAt: block.timestamp
		});
		
		addressToIndex[walletAddress] = index;
		lastIndexUsed = index;
	}

	function removeEntity (address walletAddress) private {
	    if (addressToIndex[walletAddress] == 0) {
            return;
        }
        
        uint256 index = addressToIndex[walletAddress];
        addressToIndex[walletAddress] = 0;
        
        if (index != lastIndexUsed) {
            indexToEntity[index] = indexToEntity[lastIndexUsed];
            addressToIndex[indexToEntity[lastIndexUsed]._key] = index;
        }
        
        indexToEntity[lastIndexUsed]._isValid = false;
        lastIndexUsed = lastIndexUsed.sub(1);
	}
	
	function shuffleEntities(uint256 intA, uint256 intB) private {
	    // Interval of 1 to lastIndexUsed - 1
	    intA = intA.mod(lastIndexUsed - 1) + 1;
	    intB = intB.mod(lastIndexUsed - 1) + 1;
	    
	    Entity memory entityA = indexToEntity[intA];
	    Entity memory entityB = indexToEntity[intB];
	    
	    if (entityA._isValid && entityB._isValid) {
	        addressToIndex[entityA._key] = intB;
	        addressToIndex[entityB._key] = intA;
	        
	        indexToEntity[intA] = entityB;
	        indexToEntity[intB] = entityA;
	    }
	}
	
	function getEntityListLength () public view returns (uint256) {
	    return lastIndexUsed;
	}
	
	function getEntity (uint256 index, bool shouldReject) private view returns (Entity memory) {
	    if (shouldReject == true) {
	        require(index <= getEntityListLength(), "Index out of range");
	    }
	    return indexToEntity[index];
	}

}