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BasicToken.sol

pragma solidity ^0.4.24;


import "./ERC20Basic.sol";
import "./SafeMath.sol";


/**
 * @title Basic token
 * @dev Basic version of StandardToken, with no allowances.
 */
contract BasicToken is ERC20Basic {
  using SafeMath for uint256;

  mapping(address => uint256) internal balances;

  uint256 internal totalSupply_;

  /**
  * @dev Total number of tokens in existence
  */
  function totalSupply() public view returns (uint256) {
    return totalSupply_;
  }

  /**
  * @dev Transfer token for a specified address
  * @param _to The address to transfer to.
  * @param _value The amount to be transferred.
  */
  function transfer(address _to, uint256 _value) public returns (bool) {
    require(_value <= balances[msg.sender]);
    require(_to != address(0));

    balances[msg.sender] = balances[msg.sender].sub(_value);
    balances[_to] = balances[_to].add(_value);
    emit Transfer(msg.sender, _to, _value);
    return true;
  }

  /**
  * @dev Gets the balance of the specified address.
  * @param _owner The address to query the the balance of.
  * @return An uint256 representing the amount owned by the passed address.
  */
  function balanceOf(address _owner) public view returns (uint256) {
    return balances[_owner];
  }

}

DetailedERC20.sol

pragma solidity ^0.4.24;

import "./ERC20.sol";


/**
 * @title DetailedERC20 token
 * @dev The decimals are only for visualization purposes.
 * All the operations are done using the smallest and indivisible token unit,
 * just as on Ethereum all the operations are done in wei.
 */
contract DetailedERC20 is ERC20 {
  string public name;
  string public symbol;
  uint8 public decimals;

  constructor(string _name, string _symbol, uint8 _decimals) public {
    name = _name;
    symbol = _symbol;
    decimals = _decimals;
  }
}

DSMath.sol

/// math.sol -- mixin for inline numerical wizardry

// Copyright (C) 2015, 2016, 2017  DappHub, LLC

// Licensed under the Apache License, Version 2.0 (the "License").
// You may not use this file except in compliance with the License.

// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND (express or implied).

pragma solidity ^0.4.21;

contract DSMath {
    
    /*
    standard uint256 functions
     */

    function add(uint256 x, uint256 y) constant internal returns (uint256 z) {
        assert((z = x + y) >= x);
    }

    function sub(uint256 x, uint256 y) constant internal returns (uint256 z) {
        assert((z = x - y) <= x);
    }

    function mul(uint256 x, uint256 y) constant internal returns (uint256 z) {
        assert((z = x * y) >= x);
    }

    function div(uint256 x, uint256 y) constant internal returns (uint256 z) {
        z = x / y;
    }

    function min(uint256 x, uint256 y) constant internal returns (uint256 z) {
        return x <= y ? x : y;
    }
    function max(uint256 x, uint256 y) constant internal returns (uint256 z) {
        return x >= y ? x : y;
    }

    /*
    uint128 functions (h is for half)
     */


    function hadd(uint128 x, uint128 y) constant internal returns (uint128 z) {
        assert((z = x + y) >= x);
    }

    function hsub(uint128 x, uint128 y) constant internal returns (uint128 z) {
        assert((z = x - y) <= x);
    }

    function hmul(uint128 x, uint128 y) constant internal returns (uint128 z) {
        assert((z = x * y) >= x);
    }

    function hdiv(uint128 x, uint128 y) constant internal returns (uint128 z) {
        z = x / y;
    }

    function hmin(uint128 x, uint128 y) constant internal returns (uint128 z) {
        return x <= y ? x : y;
    }
    function hmax(uint128 x, uint128 y) constant internal returns (uint128 z) {
        return x >= y ? x : y;
    }


    /*
    int256 functions
     */

    function imin(int256 x, int256 y) constant internal returns (int256 z) {
        return x <= y ? x : y;
    }
    function imax(int256 x, int256 y) constant internal returns (int256 z) {
        return x >= y ? x : y;
    }

    /*
    WAD math
     */

    uint128 constant WAD = 10 ** 18;

    function wadd(uint128 x, uint128 y) constant internal returns (uint128) {
        return hadd(x, y);
    }

    function wsub(uint128 x, uint128 y) constant internal returns (uint128) {
        return hsub(x, y);
    }

    function wmul(uint128 x, uint128 y) constant internal returns (uint128 z) {
        z = cast((uint256(x) * y + WAD / 2) / WAD);
    }

    function wdiv(uint128 x, uint128 y) constant internal returns (uint128 z) {
        z = cast((uint256(x) * WAD + y / 2) / y);
    }

    function wmin(uint128 x, uint128 y) constant internal returns (uint128) {
        return hmin(x, y);
    }
    function wmax(uint128 x, uint128 y) constant internal returns (uint128) {
        return hmax(x, y);
    }

    /*
    RAY math
     */

    uint128 constant RAY = 10 ** 27;

    function radd(uint128 x, uint128 y) constant internal returns (uint128) {
        return hadd(x, y);
    }

    function rsub(uint128 x, uint128 y) constant internal returns (uint128) {
        return hsub(x, y);
    }

    function rmul(uint128 x, uint128 y) constant internal returns (uint128 z) {
        z = cast((uint256(x) * y + RAY / 2) / RAY);
    }

    function rdiv(uint128 x, uint128 y) constant internal returns (uint128 z) {
        z = cast((uint256(x) * RAY + y / 2) / y);
    }

    function rpow(uint128 x, uint64 n) constant internal returns (uint128 z) {
        // This famous algorithm is called "exponentiation by squaring"
        // and calculates x^n with x as fixed-point and n as regular unsigned.
        //
        // It's O(log n), instead of O(n) for naive repeated multiplication.
        //
        // These facts are why it works:
        //
        //  If n is even, then x^n = (x^2)^(n/2).
        //  If n is odd,  then x^n = x * x^(n-1),
        //   and applying the equation for even x gives
        //    x^n = x * (x^2)^((n-1) / 2).
        //
        //  Also, EVM division is flooring and
        //    floor[(n-1) / 2] = floor[n / 2].

        z = n % 2 != 0 ? x : RAY;

        for (n /= 2; n != 0; n /= 2) {
            x = rmul(x, x);

            if (n % 2 != 0) {
                z = rmul(z, x);
            }
        }
    }

    function rmin(uint128 x, uint128 y) constant internal returns (uint128) {
        return hmin(x, y);
    }
    function rmax(uint128 x, uint128 y) constant internal returns (uint128) {
        return hmax(x, y);
    }

    function cast(uint256 x) constant internal returns (uint128 z) {
        assert((z = uint128(x)) == x);
    }

}

ERC20.sol

pragma solidity ^0.4.24;

import "./ERC20Basic.sol";


/**
 * @title ERC20 interface
 * @dev see https://github.com/ethereum/EIPs/issues/20
 */
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
  );
}

ERC20Basic.sol

pragma solidity ^0.4.24;


/**
 * @title ERC20Basic
 * @dev Simpler version of ERC20 interface
 * See https://github.com/ethereum/EIPs/issues/179
 */
contract ERC20Basic {
  function totalSupply() public view returns (uint256);
  function balanceOf(address _who) public view returns (uint256);
  function transfer(address _to, uint256 _value) public returns (bool);
  event Transfer(address indexed from, address indexed to, uint256 value);
}

MintableToken.sol

pragma solidity ^0.4.24;

import "./StandardToken.sol";
import "./Ownable.sol";


/**
 * @title Mintable token
 * @dev Simple ERC20 Token example, with mintable token creation
 * Based on code by TokenMarketNet: https://github.com/TokenMarketNet/ico/blob/master/contracts/MintableToken.sol
 */
contract MintableToken is StandardToken, Ownable {
  event Mint(address indexed to, uint256 amount);
  event MintFinished();

  bool public mintingFinished = false;


  modifier canMint() {
    require(!mintingFinished);
    _;
  }

  modifier hasMintPermission() {
    require(msg.sender == owner);
    _;
  }

  /**
   * @dev Function to mint tokens
   * @param _to The address that will receive the minted tokens.
   * @param _amount The amount of tokens to mint.
   * @return A boolean that indicates if the operation was successful.
   */
  function mint(
    address _to,
    uint256 _amount
  )
    public
    hasMintPermission
    canMint
    returns (bool)
  {
    totalSupply_ = totalSupply_.add(_amount);
    balances[_to] = balances[_to].add(_amount);
    emit Mint(_to, _amount);
    emit Transfer(address(0), _to, _amount);
    return true;
  }

  /**
   * @dev Function to stop minting new tokens.
   * @return True if the operation was successful.
   */
  function finishMinting() public onlyOwner canMint returns (bool) {
    mintingFinished = true;
    emit MintFinished();
    return true;
  }
}

Ownable.sol

pragma solidity ^0.4.24;


/**
 * @title Ownable
 * @dev The Ownable contract has an owner address, and provides basic authorization control
 * functions, this simplifies the implementation of "user permissions".
 */
contract Ownable {
  address public owner;


  event OwnershipRenounced(address indexed previousOwner);
  event OwnershipTransferred(
    address indexed previousOwner,
    address indexed newOwner
  );


  /**
   * @dev The Ownable constructor sets the original `owner` of the contract to the sender
   * account.
   */
  constructor() public {
    owner = msg.sender;
  }

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

  /**
   * @dev Allows the current owner to relinquish control of the contract.
   * @notice Renouncing to ownership will leave the contract without an owner.
   * It will not be possible to call the functions with the `onlyOwner`
   * modifier anymore.
   */
  function renounceOwnership() public onlyOwner {
    emit OwnershipRenounced(owner);
    owner = address(0);
  }

  /**
   * @dev Allows the current owner to transfer control of the contract to a newOwner.
   * @param _newOwner The address to transfer ownership to.
   */
  function transferOwnership(address _newOwner) public onlyOwner {
    _transferOwnership(_newOwner);
  }

  /**
   * @dev Transfers control of the contract to a newOwner.
   * @param _newOwner The address to transfer ownership to.
   */
  function _transferOwnership(address _newOwner) internal {
    require(_newOwner != address(0));
    emit OwnershipTransferred(owner, _newOwner);
    owner = _newOwner;
  }
}

PotatoToken.sol

pragma solidity ^0.4.21;

import './MintableToken.sol';
import './DetailedERC20.sol';
import './Ownable.sol';

contract PotatoToken is MintableToken, DetailedERC20 {
    uint256 public constant INITIAL_SUPPLY = 0;

    constructor() public DetailedERC20("PotatoToken", "PC", 18) {
        // name = "PotatoToken";
        // symbol = "PC";
        // decimals = 18;
        totalSupply_ = INITIAL_SUPPLY;
        balances[msg.sender] = INITIAL_SUPPLY;
    }

    function totalSupply() public view returns (uint256) {
        return totalSupply_;
    }
}

PotatoTokenSale.sol

pragma solidity ^0.4.21;

import 'openzeppelin-solidity/contracts/ownership/Ownable.sol';
import './PotatoToken.sol';
import './DSMath.sol';

contract PotatoTokenSale is Ownable, DSMath
{
    bool public closed;
    uint256 public priceInWei;
    PotatoToken public POTATO;
    uint128  public  totalSupply;          // Total POTATO amount created
    uint128  public  foundersAllocation;   // Amount given to founders
    string   public  foundersKey;          // Public key of founders

    // uint     public  openTime;             // Time of window 0 opening
    uint     public  createFirstDay;       // Tokens sold in window 0

    uint     public  startTime;            // Time of window 1 opening
    uint     public  numberOfDays;         // Number of windows after 0
    uint     public  createPerDay;         // Tokens sold in each window

    mapping (uint => uint)                       public  dailyTotals;
    mapping (uint => mapping (address => uint))  public  userBuys;
    mapping (uint => mapping (address => bool))  public  claimed;
    mapping (address => string)                  public  keys;

    event LogBuy      (uint window, address user, uint amount);
    event LogClaim    (uint window, address user, uint amount);
    event LogRegister (address user, string key);
    event LogCollect  (uint amount);
    event LogFreeze   ();

    constructor(
        uint     _numberOfDays,
        uint128  _totalSupply,
        // uint     _openTime,
        // uint     _startTime,
        uint128  _foundersAllocation,
        string   _foundersKey)
        public
    {
        numberOfDays       = _numberOfDays;
        totalSupply        = _totalSupply;
        // openTime           = _openTime;
        // startTime          = _startTime;
        foundersAllocation = _foundersAllocation;
        foundersKey        = _foundersKey;

        createFirstDay = wmul(totalSupply, 0.2 ether);
        createPerDay = div(
            sub(sub(totalSupply, foundersAllocation), createFirstDay),
            numberOfDays
        );

        assert(numberOfDays > 0);
        assert(totalSupply > foundersAllocation);
        // assert(openTime < startTime);
        startTime = time();
    }

    function initialize(PotatoToken potato) public onlyOwner
    {
        assert(address(POTATO) == address(0));
        assert(potato.owner() == address(this));
        assert(potato.totalSupply() == 0);

        POTATO = potato;

        POTATO.mint(owner, totalSupply);

        // Address 0xb1 is provably non-transferrable
        // POTATO.push(0xb1, foundersAllocation);
        // POTATO.transfer(0xb1, foundersAllocation);
        POTATO.transferFrom(owner, 0xb1, foundersAllocation);
        keys[0xb1] = foundersKey;
        LogRegister(0xb1, foundersKey);
    }

    function time() public view returns (uint)
    {
        return block.timestamp;
    }

    function today() public view returns (uint)
    {
        return dayFor(time());
    }

    // Each window is 23 hours long so that end-of-window rotates
    // around the clock for all timezones.
    function dayFor(uint timestamp) public view returns (uint)
    {
        return timestamp < startTime
            ? 0
            : sub(timestamp, startTime) / 23 hours + 1;
    }

    function createOnDay(uint day) public view returns (uint)
    {
        return day == 0 ? createFirstDay : createPerDay;
    }

    // This method provides the buyer some protections regarding which
    // day the buy order is submitted and the maximum price prior to
    // applying this payment that will be allowed.
    function buyWithLimit(uint day, uint limit) public payable
    {
        // assert(time() >= openTime && today() <= numberOfDays);
        assert(today() <= numberOfDays);
        assert(msg.value >= 0.01 ether);

        assert(day >= today());
        assert(day <= numberOfDays);

        userBuys[day][msg.sender] += msg.value;
        dailyTotals[day] += msg.value;

        if (limit != 0) {
            assert(dailyTotals[day] <= limit);
        }

        LogBuy(day, msg.sender, msg.value);
    }

    function buy() public payable
    {
        buyWithLimit(today(), 0);
    }

    function () public payable
    {
        buy();
    }

    function claim(uint day) public
    {
        assert(today() > day);

        if (claimed[day][msg.sender] || dailyTotals[day] == 0) {
            return;
        }

        // This will have small rounding errors, but the token is
        // going to be truncated to 8 decimal places or less anyway
        // when launched on its own chain.

        var dailyTotal = cast(dailyTotals[day]);
        var userTotal  = cast(userBuys[day][msg.sender]);
        var price      = wdiv(cast(createOnDay(day)), dailyTotal);
        var reward     = wmul(price, userTotal);

        claimed[day][msg.sender] = true;
        // POTATO.push(msg.sender, reward);
        POTATO.transferFrom(owner, msg.sender, reward);

        LogClaim(day, msg.sender, reward);
    }

    function claimAll() public
    {
        for (uint i = 0; i < today(); i++) {
            claim(i);
        }
    }

    // Value should be a public key.  Read full key import policy.
    // Manually registering requires a base58
    // encoded using the STEEM, BTS, or POTATO public key format.
    function register(string key) public
    {
        assert(today() <=  numberOfDays + 1);
        assert(bytes(key).length <= 64);

        keys[msg.sender] = key;

        LogRegister(msg.sender, key);
    }

    // Crowdsale owners can collect ETH any number of times
    function collect() public onlyOwner
    {
        assert(today() > 0); // Prevent recycling during window 0
        owner.transfer(address(this).balance);
        LogCollect(this.balance);
    }

    // Anyone can freeze the token 1 day after the sale ends
    function freeze() public 
    {
        assert(today() > numberOfDays + 1);
        POTATO.finishMinting();
        LogFreeze();
    }

    function getDailyTotals() public view returns (uint[351] result)
    {
        for (uint i = 0; i < 351; i++)
        {
            result[i] = this.dailyTotals(i);
        }
    }

    function getUserBuys(address user) public view returns (uint[351] result)
    {
        for (uint i = 0; i < 351; i++)
        {
            result[i] = this.userBuys(i, user);
        }
    }

    function getUserClaims(address user) public view returns (bool[351] result)
    {
        for (uint i = 0; i < 351; i++)
        {
            result[i] = this.claimed(i, user);
        }
    }
}

SafeMath.sol

pragma solidity ^0.4.24;


/**
 * @title SafeMath
 * @dev Math operations with safety checks that throw on error
 */
library SafeMath {

  /**
  * @dev Multiplies two numbers, throws on overflow.
  */
  function mul(uint256 _a, uint256 _b) internal pure returns (uint256 c) {
    // Gas optimization: this is cheaper than asserting 'a' not being zero, but the
    // benefit is lost if 'b' is also tested.
    // See: https://github.com/OpenZeppelin/openzeppelin-solidity/pull/522
    if (_a == 0) {
      return 0;
    }

    c = _a * _b;
    assert(c / _a == _b);
    return c;
  }

  /**
  * @dev Integer division of two numbers, truncating the quotient.
  */
  function div(uint256 _a, uint256 _b) internal pure returns (uint256) {
    // assert(_b > 0); // Solidity automatically throws when dividing by 0
    // uint256 c = _a / _b;
    // assert(_a == _b * c + _a % _b); // There is no case in which this doesn't hold
    return _a / _b;
  }

  /**
  * @dev Subtracts two numbers, throws on overflow (i.e. if subtrahend is greater than minuend).
  */
  function sub(uint256 _a, uint256 _b) internal pure returns (uint256) {
    assert(_b <= _a);
    return _a - _b;
  }

  /**
  * @dev Adds two numbers, throws on overflow.
  */
  function add(uint256 _a, uint256 _b) internal pure returns (uint256 c) {
    c = _a + _b;
    assert(c >= _a);
    return c;
  }
}

StandardToken.sol

pragma solidity ^0.4.24;

import "./BasicToken.sol";
import "./ERC20.sol";


/**
 * @title Standard ERC20 token
 *
 * @dev Implementation of the basic standard token.
 * https://github.com/ethereum/EIPs/issues/20
 * Based on code by FirstBlood: https://github.com/Firstbloodio/token/blob/master/smart_contract/FirstBloodToken.sol
 */
contract StandardToken is ERC20, BasicToken {

  mapping (address => mapping (address => uint256)) internal allowed;


  /**
   * @dev Transfer tokens from one address to another
   * @param _from address The address which you want to send tokens from
   * @param _to address The address which you want to transfer to
   * @param _value uint256 the amount of tokens to be transferred
   */
  function transferFrom(
    address _from,
    address _to,
    uint256 _value
  )
    public
    returns (bool)
  {
    require(_value <= balances[_from]);
    require(_value <= allowed[_from][msg.sender]);
    require(_to != address(0));

    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;
  }

  /**
   * @dev Approve the passed address to spend the specified amount of tokens on behalf of msg.sender.
   * 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
   * @param _spender The address which will spend the funds.
   * @param _value The amount of tokens to be spent.
   */
  function approve(address _spender, uint256 _value) public returns (bool) {
    allowed[msg.sender][_spender] = _value;
    emit Approval(msg.sender, _spender, _value);
    return true;
  }

  /**
   * @dev Function to check the amount of tokens that an owner allowed to a spender.
   * @param _owner address The address which owns the funds.
   * @param _spender address The address which will spend the funds.
   * @return A uint256 specifying the amount of tokens still available for the spender.
   */
  function allowance(
    address _owner,
    address _spender
   )
    public
    view
    returns (uint256)
  {
    return allowed[_owner][_spender];
  }

  /**
   * @dev Increase the amount of tokens that an owner allowed to a spender.
   * approve should be called when allowed[_spender] == 0. To increment
   * allowed value is better to use this function to avoid 2 calls (and wait until
   * the first transaction is mined)
   * From MonolithDAO Token.sol
   * @param _spender The address which will spend the funds.
   * @param _addedValue The amount of tokens to increase the allowance by.
   */
  function increaseApproval(
    address _spender,
    uint256 _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;
  }

  /**
   * @dev Decrease the amount of tokens that an owner allowed to a spender.
   * approve should be called when allowed[_spender] == 0. To decrement
   * allowed value is better to use this function to avoid 2 calls (and wait until
   * the first transaction is mined)
   * From MonolithDAO Token.sol
   * @param _spender The address which will spend the funds.
   * @param _subtractedValue The amount of tokens to decrease the allowance by.
   */
  function decreaseApproval(
    address _spender,
    uint256 _subtractedValue
  )
    public
    returns (bool)
  {
    uint256 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;
  }

}