// File: contracts/Sale.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.19;

import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
import "@chainlink/contracts/src/v0.8/interfaces/AggregatorV3Interface.sol";

contract Sale is Ownable {
    IERC20 private immutable _KUMA;
    AggregatorV3Interface private immutable _PRICEFEED;

    uint256 public rate;
    uint256 public awaitingOwners;
    bool public isStarted;
    bool public isWithdrawable;

    mapping (address => bool) private _whitelist;
    mapping (address => uint256) private _availableToWithdraw; 

    constructor(address _kuma, address _pricefeed, uint256 _cost) {
        _KUMA = IERC20(_kuma);
        rate = _cost;
        // 0x5f4eC3Df9cbd43714FE2740f5E3616155c5b8419
        _PRICEFEED = AggregatorV3Interface(_pricefeed);
    }

    receive() external payable {
        _buy();
    }

    function _buy() private {
        if (!isStarted || !_whitelist[msg.sender]) {

        }
        else {
        uint256 _wei = msg.value;
        uint256 _usd = _getConversionRate(_wei);
        uint256 _tokensAmount = _usd * rate;
        uint256 _amountToSendNow = _calculateStartedPercent(_tokensAmount);
        _availableToWithdraw[msg.sender] += _tokensAmount - _amountToSendNow;
        awaitingOwners += _tokensAmount - _amountToSendNow;
        _KUMA.transfer(msg.sender, _amountToSendNow);
        }
    }

    function withdraw() external {
        require(isWithdrawable);
        uint256 _amountTotransfer = _availableToWithdraw[msg.sender];
        awaitingOwners -= _amountTotransfer;
        _KUMA.transfer(msg.sender, _amountTotransfer);
        _availableToWithdraw[msg.sender] = 0;
    }

    /* OWNER */

    function withdrawAll() external onlyOwner {
        uint256 balance = _KUMA.balanceOf(address(this));
        _KUMA.transfer(msg.sender, balance - awaitingOwners);
    }

    function withdrawOwnable() external onlyOwner {
        payable(msg.sender).transfer(address(this).balance);
    }

    function startSale() external onlyOwner {
        isStarted = true;
    }

    function stopSale() external onlyOwner {
        isStarted = false;
    }

    function startWithdraw() external onlyOwner {
        isWithdrawable = true;
    }

        function addInWhitelist(address[] calldata _users) external onlyOwner {
        for (uint i = 0; i < _users.length; i++) {
            _whitelist[_users[i]] = true;
        }
    }

    /* GETTERS */

    function getPrice() public view returns (uint256) {
         (,int256 price,,,) = _PRICEFEED.latestRoundData();
        return uint256(price * (1 * 10 ** 10));
    }

    function _getConversionRate(uint256 _amount) private view returns (uint256) {
        uint256 _ethPrice = getPrice();
        uint256 _ethInUSD = (_ethPrice * _amount) / (1 * 10 ** 18);
        return _ethInUSD;
    }

    function getTokenBalance() public view returns (uint256) {
        uint256 _balance = _KUMA.balanceOf(address(this));
        return _balance;
    }

    function getMaticBalance() public view returns (uint256) {
        address _this = address(this);
        uint256 _balance = _this.balance;
        return _balance;
    }

    function getUSDBalance() public view returns (uint) {
        uint256 _balance = getMaticBalance();
        uint256 _usd = _getConversionRate(_balance);
        return _usd;
    }

    function _calculateStartedPercent(uint256 _amount) private pure returns (uint256) {
        return (_amount * 3000) / 10000;
    }
}
// File: @chainlink/contracts/src/v0.8/interfaces/AggregatorV3Interface.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

interface AggregatorV3Interface {
  function decimals() external view returns (uint8);

  function description() external view returns (string memory);

  function version() external view returns (uint256);

  function getRoundData(uint80 _roundId)
    external
    view
    returns (
      uint80 roundId,
      int256 answer,
      uint256 startedAt,
      uint256 updatedAt,
      uint80 answeredInRound
    );

  function latestRoundData()
    external
    view
    returns (
      uint80 roundId,
      int256 answer,
      uint256 startedAt,
      uint256 updatedAt,
      uint80 answeredInRound
    );
}

// File: @openzeppelin/contracts/access/Ownable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)

pragma solidity ^0.8.0;

import "../utils/Context.sol";

/**
 * @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() {
        _transferOwnership(_msgSender());
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        _checkOwner();
        _;
    }

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

    /**
     * @dev Throws if the sender is not the owner.
     */
    function _checkOwner() internal view virtual {
        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 {
        _transferOwnership(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");
        _transferOwnership(newOwner);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Internal function without access restriction.
     */
    function _transferOwnership(address newOwner) internal virtual {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}

// File: @openzeppelin/contracts/token/ERC20/IERC20.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @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 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 `to`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address to, 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 `from` to `to` 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 from,
        address to,
        uint256 amount
    ) external returns (bool);
}

// File: @openzeppelin/contracts/utils/Context.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)

pragma solidity ^0.8.0;

/**
 * @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) {
        return msg.data;
    }
}