//SPDX-License-Identifier: MIT

pragma solidity ^0.7.6;

interface IERC20 {
    function totalSupply() external view returns (uint);
    function balanceOf(address account) external view returns (uint);
    function transfer(address recipient, uint amount) external returns (bool);
    function allowance(address owner, address spender) external view returns (uint);
    function approve(address spender, uint amount) external returns (bool);
    function transferFrom(address sender, address recipient, uint amount) external returns (bool);
    event Transfer(address indexed from, address indexed to, uint value);
    event Approval(address indexed owner, address indexed spender, uint value);
}


contract Context {
    constructor () public { }
    // solhint-disable-previous-line no-empty-blocks

    function _msgSender() internal view returns (address payable) {
        return msg.sender;
    }
}

contract Ownable {
    address public owner;

    constructor () public {
        owner = msg.sender;
    }

    modifier onlyOwner() {
        if (msg.sender == owner)
            _;
    }

    function transferOwnership(address newOwner) public onlyOwner {
        if (newOwner != address(0)) owner = newOwner;
    }
}
contract ERC20 is Context, IERC20 {
    using SafeMath for uint;

    mapping (address => uint) internal _balances;

    mapping (address => mapping (address => uint)) internal _allowances;

    uint internal _totalSupply;
   
    
    function totalSupply() public view override returns (uint) {
        return _totalSupply;
    }
    function balanceOf(address account) public view override returns (uint) {
        return _balances[account];
    }
    function transfer(address recipient, uint amount) public override  returns (bool) {
        _transfer(_msgSender(), recipient, amount);
        return true;
    }
    function allowance(address owner, address spender) public view override returns (uint) {
        return _allowances[owner][spender];
    }
    function approve(address spender, uint amount) public override returns (bool) {
        _approve(_msgSender(), spender, amount);
        return true;
    }
    function transferFrom(address sender, address recipient, uint 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 increaseAllowance(address spender, uint addedValue) public returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].add(addedValue));
        return true;
    }
    function decreaseAllowance(address spender, uint subtractedValue) public returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].sub(subtractedValue, "ERC20: decreased allowance below zero"));
        return true;
    }
    function _transfer(address sender, address recipient, uint amount) internal {
        require(sender != address(0), "ERC20: transfer from the zero address");
        require(recipient != address(0), "ERC20: transfer to the zero address");

        _balances[sender] = _balances[sender].sub(amount, "ERC20: transfer amount exceeds balance");
        _balances[recipient] = _balances[recipient].add(amount);
        emit Transfer(sender, recipient, amount);
    }
   
 
    function _approve(address owner, address spender, uint amount) internal {
        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);
    }
    
 
    
}
contract ERC20Detailed is ERC20 {
    string private _name;
    string private _symbol;
    uint8 private _decimals;

    constructor (string memory name, string memory symbol, uint8 decimals) public{
        _name = name;
        _symbol = symbol;
        _decimals = decimals;
        
    }
    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;
    }
}

library SafeMath {
    function add(uint a, uint b) internal pure returns (uint) {
        uint c = a + b;
        require(c >= a, "SafeMath: addition overflow");

        return c;
    }
    function sub(uint a, uint b) internal pure returns (uint) {
        return sub(a, b, "SafeMath: subtraction overflow");
    }
    function sub(uint a, uint b, string memory errorMessage) internal pure returns (uint) {
        require(b <= a, errorMessage);
        uint c = a - b;

        return c;
    }
    function mul(uint a, uint b) internal pure returns (uint) {
        if (a == 0) {
            return 0;
        }

        uint c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");

        return c;
    }
    function div(uint a, uint b) internal pure returns (uint) {
        return div(a, b, "SafeMath: division by zero");
    }
    function div(uint a, uint b, string memory errorMessage) internal pure returns (uint) {
        // Solidity only automatically asserts when dividing by 0
        require(b > 0, errorMessage);
        uint c = a / b;

        return c;
    }
}

library Address {
    function isContract(address account) internal view returns (bool) {
        bytes32 codehash;
        bytes32 accountHash = 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470;
        // solhint-disable-next-line no-inline-assembly
        assembly { codehash := extcodehash(account) }
        return (codehash != 0x0 && codehash != accountHash);
    }
}

library SafeERC20 {
    using SafeMath for uint;
    using Address for address;

    function safeTransfer(IERC20 token, address to, uint value) internal {
        callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }

    function safeTransferFrom(IERC20 token, address from, address to, uint value) internal {
        callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }

    function safeApprove(IERC20 token, address spender, uint value) internal {
        require((value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeERC20: approve from non-zero to non-zero allowance"
        );
        callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
    }
    function callOptionalReturn(IERC20 token, bytes memory data) private {
        require(address(token).isContract(), "SafeERC20: call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = address(token).call(data);
        require(success, "SafeERC20: low-level call failed");

        if (returndata.length > 0) { // Return data is optional
            // solhint-disable-next-line max-line-length
            require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
        }
    }
}

  
interface AggregatorV3Interface {

  function decimals() external view returns (uint8);
  function description() external view returns (string memory);
  function version() external view returns (uint256);

  // getRoundData and latestRoundData should both raise "No data present"
  // if they do not have data to report, instead of returning unset values
  // which could be misinterpreted as actual reported values.
  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
    );

}
contract PriceConsumerV3 {

    AggregatorV3Interface internal priceFeed;

    constructor() public {
        // Mainnet address : 0xEe9F2375b4bdF6387aa8265dD4FB8F16512A1d46
        //Kovan test netwoek: 0x0bF499444525a23E7Bb61997539725cA2e928138
        priceFeed = AggregatorV3Interface(0xEe9F2375b4bdF6387aa8265dD4FB8F16512A1d46);
}
    /**
     * Returns the latest price
     */
    function getLatestPrice() public view returns (int) {
        (
            uint80 roundID, 
            int price,
            uint startedAt,
            uint timeStamp,
            uint80 answeredInRound
        ) = priceFeed.latestRoundData();
        return price;
    }
    
}

contract SS is ERC20, ERC20Detailed, PriceConsumerV3{
  using SafeERC20 for IERC20;
  using Address for address;
  using SafeMath for uint;

  constructor () ERC20Detailed("SS Token", "SS", 18) PriceConsumerV3() public{

    _totalSupply = 5000000000 * (10**uint256(18)) ;
	_balances[msg.sender] = _totalSupply;
  }
}


contract tokenSale is Ownable, PriceConsumerV3{
     
    using SafeMath for uint256;

  // The token being sold
    ERC20 public token;
    address public _owner = msg.sender;
    address payable wallet;
   
    constructor(ERC20 _token) public
    {
         
         require(address(_token) != address(0));

    
    wallet = msg.sender;
    token = _token;
    }
    fallback () payable external{
        buy(msg.sender);
    }
    
    receive() payable external {
        buy(msg.sender);
    }
    uint256 public weiUSD;
   
    uint256 public amountOfTokens;
    
    
    function _forwardFunds(uint256 _weiUSD) internal 
    {
        wallet.transfer(_weiUSD);
    }
    
    function buy(address beneficiary) payable  public
    {
        require(msg.value > 0 ether," No value transfered");
        weiUSD = (uint256)(getLatestPrice());
        require(weiUSD != 0, " No exchange value returned. Try again");
       
        uint256 unitPrice = msg.value.div(weiUSD);
        
        amountOfTokens =  unitPrice * uint256(10**18); //1 SS token * USDC amount of Value
        
        _forwardFunds(weiUSD);
      

        token.transfer(beneficiary, amountOfTokens);
    
    }
   
}