pragma solidity ^0.4.24;

// File: openzeppelin-solidity/contracts/token/ERC20/IERC20.sol

/**
 * @title ERC20 interface
 * @dev see https://github.com/ethereum/EIPs/issues/20
 */
interface IERC20 {
  function totalSupply() external view returns (uint256);

  function balanceOf(address who) external view returns (uint256);

  function allowance(address owner, address spender)
    external view returns (uint256);

  function transfer(address to, uint256 value) external returns (bool);

  function approve(address spender, uint256 value)
    external returns (bool);

  function transferFrom(address from, address to, uint256 value)
    external returns (bool);

  event Transfer(
    address indexed from,
    address indexed to,
    uint256 value
  );

  event Approval(
    address indexed owner,
    address indexed spender,
    uint256 value
  );
}

// File: openzeppelin-solidity/contracts/math/SafeMath.sol

/**
 * @title SafeMath
 * @dev Math operations with safety checks that revert on error
 */
library SafeMath {

  /**
  * @dev Multiplies two numbers, reverts on 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-solidity/pull/522
    if (a == 0) {
      return 0;
    }

    uint256 c = a * b;
    require(c / a == b);

    return c;
  }

  /**
  * @dev Integer division of two numbers truncating the quotient, reverts on division by zero.
  */
  function div(uint256 a, uint256 b) internal pure returns (uint256) {
    require(b > 0); // Solidity only automatically asserts 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 c;
  }

  /**
  * @dev Subtracts two numbers, reverts on overflow (i.e. if subtrahend is greater than minuend).
  */
  function sub(uint256 a, uint256 b) internal pure returns (uint256) {
    require(b <= a);
    uint256 c = a - b;

    return c;
  }

  /**
  * @dev Adds two numbers, reverts on overflow.
  */
  function add(uint256 a, uint256 b) internal pure returns (uint256) {
    uint256 c = a + b;
    require(c >= a);

    return c;
  }

  /**
  * @dev Divides two numbers and returns the remainder (unsigned integer modulo),
  * reverts when dividing by zero.
  */
  function mod(uint256 a, uint256 b) internal pure returns (uint256) {
    require(b != 0);
    return a % b;
  }
}

// File: openzeppelin-solidity/contracts/token/ERC20/SafeERC20.sol

/**
 * @title SafeERC20
 * @dev Wrappers around ERC20 operations that throw on failure.
 * To use this library you can add a `using SafeERC20 for ERC20;` statement to your contract,
 * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
 */
library SafeERC20 {
  function safeTransfer(
    IERC20 token,
    address to,
    uint256 value
  )
    internal
  {
    require(token.transfer(to, value));
  }

  function safeTransferFrom(
    IERC20 token,
    address from,
    address to,
    uint256 value
  )
    internal
  {
    require(token.transferFrom(from, to, value));
  }

  function safeApprove(
    IERC20 token,
    address spender,
    uint256 value
  )
    internal
  {
    require(token.approve(spender, value));
  }
}

// File: openzeppelin-solidity/contracts/crowdsale/Crowdsale.sol

/**
 * @title Crowdsale
 * @dev Crowdsale is a base contract for managing a token crowdsale,
 * allowing investors to purchase tokens with ether. This contract implements
 * such functionality in its most fundamental form and can be extended to provide additional
 * functionality and/or custom behavior.
 * The external interface represents the basic interface for purchasing tokens, and conform
 * the base architecture for crowdsales. They are *not* intended to be modified / overridden.
 * The internal interface conforms the extensible and modifiable surface of crowdsales. Override
 * the methods to add functionality. Consider using 'super' where appropriate to concatenate
 * behavior.
 */
contract Crowdsale {
  using SafeMath for uint256;
  using SafeERC20 for IERC20;

  // The token being sold
  IERC20 private _token;

  // Address where funds are collected
  address private _wallet;

  // How many token units a buyer gets per wei.
  // The rate is the conversion between wei and the smallest and indivisible token unit.
  // So, if you are using a rate of 1 with a ERC20Detailed token with 3 decimals called TOK
  // 1 wei will give you 1 unit, or 0.001 TOK.
  uint256 private _rate;

  // Amount of wei raised
  uint256 private _weiRaised;

  /**
   * Event for token purchase logging
   * @param purchaser who paid for the tokens
   * @param beneficiary who got the tokens
   * @param value weis paid for purchase
   * @param amount amount of tokens purchased
   */
  event TokensPurchased(
    address indexed purchaser,
    address indexed beneficiary,
    uint256 value,
    uint256 amount
  );

  /**
   * @param rate Number of token units a buyer gets per wei
   * @dev The rate is the conversion between wei and the smallest and indivisible
   * token unit. So, if you are using a rate of 1 with a ERC20Detailed token
   * with 3 decimals called TOK, 1 wei will give you 1 unit, or 0.001 TOK.
   * @param wallet Address where collected funds will be forwarded to
   * @param token Address of the token being sold
   */
  constructor(uint256 rate, address wallet, IERC20 token) public {
    require(rate > 0);
    require(wallet != address(0));
    require(token != address(0));

    _rate = rate;
    _wallet = wallet;
    _token = token;
  }

  // -----------------------------------------
  // Crowdsale external interface
  // -----------------------------------------

  /**
   * @dev fallback function ***DO NOT OVERRIDE***
   */
  function () external payable {
    buyTokens(msg.sender);
  }

  /**
   * @return the token being sold.
   */
  function token() public view returns(IERC20) {
    return _token;
  }

  /**
   * @return the address where funds are collected.
   */
  function wallet() public view returns(address) {
    return _wallet;
  }

  /**
   * @return the number of token units a buyer gets per wei.
   */
  function rate() public view returns(uint256) {
    return _rate;
  }

  /**
   * @return the mount of wei raised.
   */
  function weiRaised() public view returns (uint256) {
    return _weiRaised;
  }

  /**
   * @dev low level token purchase ***DO NOT OVERRIDE***
   * @param beneficiary Address performing the token purchase
   */
  function buyTokens(address beneficiary) public payable {

    uint256 weiAmount = msg.value;
    _preValidatePurchase(beneficiary, weiAmount);

    // calculate token amount to be created
    uint256 tokens = _getTokenAmount(weiAmount);

    // update state
    _weiRaised = _weiRaised.add(weiAmount);

    _processPurchase(beneficiary, tokens);
    emit TokensPurchased(
      msg.sender,
      beneficiary,
      weiAmount,
      tokens
    );

    _updatePurchasingState(beneficiary, weiAmount);

    _forwardFunds();
    _postValidatePurchase(beneficiary, weiAmount);
  }

  // -----------------------------------------
  // Internal interface (extensible)
  // -----------------------------------------

  /**
   * @dev Validation of an incoming purchase. Use require statements to revert state when conditions are not met. Use `super` in contracts that inherit from Crowdsale to extend their validations.
   * Example from CappedCrowdsale.sol's _preValidatePurchase method:
   *   super._preValidatePurchase(beneficiary, weiAmount);
   *   require(weiRaised().add(weiAmount) <= cap);
   * @param beneficiary Address performing the token purchase
   * @param weiAmount Value in wei involved in the purchase
   */
  function _preValidatePurchase(
    address beneficiary,
    uint256 weiAmount
  )
    internal
  {
    require(beneficiary != address(0));
    require(weiAmount != 0);
  }

  /**
   * @dev Validation of an executed purchase. Observe state and use revert statements to undo rollback when valid conditions are not met.
   * @param beneficiary Address performing the token purchase
   * @param weiAmount Value in wei involved in the purchase
   */
  function _postValidatePurchase(
    address beneficiary,
    uint256 weiAmount
  )
    internal
  {
    // optional override
  }

  /**
   * @dev Source of tokens. Override this method to modify the way in which the crowdsale ultimately gets and sends its tokens.
   * @param beneficiary Address performing the token purchase
   * @param tokenAmount Number of tokens to be emitted
   */
  function _deliverTokens(
    address beneficiary,
    uint256 tokenAmount
  )
    internal
  {
    _token.safeTransfer(beneficiary, tokenAmount);
  }

  /**
   * @dev Executed when a purchase has been validated and is ready to be executed. Not necessarily emits/sends tokens.
   * @param beneficiary Address receiving the tokens
   * @param tokenAmount Number of tokens to be purchased
   */
  function _processPurchase(
    address beneficiary,
    uint256 tokenAmount
  )
    internal
  {
    _deliverTokens(beneficiary, tokenAmount);
  }

  /**
   * @dev Override for extensions that require an internal state to check for validity (current user contributions, etc.)
   * @param beneficiary Address receiving the tokens
   * @param weiAmount Value in wei involved in the purchase
   */
  function _updatePurchasingState(
    address beneficiary,
    uint256 weiAmount
  )
    internal
  {
    // optional override
  }

  /**
   * @dev Override to extend the way in which ether is converted to tokens.
   * @param weiAmount Value in wei to be converted into tokens
   * @return Number of tokens that can be purchased with the specified _weiAmount
   */
  function _getTokenAmount(uint256 weiAmount)
    internal view returns (uint256)
  {
    return weiAmount.mul(_rate);
  }

  /**
   * @dev Determines how ETH is stored/forwarded on purchases.
   */
  function _forwardFunds() internal {
    _wallet.transfer(msg.value);
  }
}

// File: openzeppelin-solidity/contracts/crowdsale/validation/TimedCrowdsale.sol

/**
 * @title TimedCrowdsale
 * @dev Crowdsale accepting contributions only within a time frame.
 */
contract TimedCrowdsale is Crowdsale {
  using SafeMath for uint256;

  uint256 private _openingTime;
  uint256 private _closingTime;

  /**
   * @dev Reverts if not in crowdsale time range.
   */
  modifier onlyWhileOpen {
    require(isOpen());
    _;
  }

  /**
   * @dev Constructor, takes crowdsale opening and closing times.
   * @param openingTime Crowdsale opening time
   * @param closingTime Crowdsale closing time
   */
  constructor(uint256 openingTime, uint256 closingTime) public {
    // solium-disable-next-line security/no-block-members
    require(openingTime >= block.timestamp);
    require(closingTime >= openingTime);

    _openingTime = openingTime;
    _closingTime = closingTime;
  }

  /**
   * @return the crowdsale opening time.
   */
  function openingTime() public view returns(uint256) {
    return _openingTime;
  }

  /**
   * @return the crowdsale closing time.
   */
  function closingTime() public view returns(uint256) {
    return _closingTime;
  }

  /**
   * @return true if the crowdsale is open, false otherwise.
   */
  function isOpen() public view returns (bool) {
    // solium-disable-next-line security/no-block-members
    return block.timestamp >= _openingTime && block.timestamp <= _closingTime;
  }

  /**
   * @dev Checks whether the period in which the crowdsale is open has already elapsed.
   * @return Whether crowdsale period has elapsed
   */
  function hasClosed() public view returns (bool) {
    // solium-disable-next-line security/no-block-members
    return block.timestamp > _closingTime;
  }

  /**
   * @dev Extend parent behavior requiring to be within contributing period
   * @param beneficiary Token purchaser
   * @param weiAmount Amount of wei contributed
   */
  function _preValidatePurchase(
    address beneficiary,
    uint256 weiAmount
  )
    internal
    onlyWhileOpen
  {
    super._preValidatePurchase(beneficiary, weiAmount);
  }

}

// File: openzeppelin-solidity/contracts/crowdsale/distribution/PostDeliveryCrowdsale.sol

/**
 * @title PostDeliveryCrowdsale
 * @dev Crowdsale that locks tokens from withdrawal until it ends.
 */
contract PostDeliveryCrowdsale is TimedCrowdsale {
  using SafeMath for uint256;

  mapping(address => uint256) private _balances;

  /**
   * @dev Withdraw tokens only after crowdsale ends.
   * @param beneficiary Whose tokens will be withdrawn.
   */
  function withdrawTokens(address beneficiary) public {
    require(hasClosed());
    uint256 amount = _balances[beneficiary];
    require(amount > 0);
    _balances[beneficiary] = 0;
    _deliverTokens(beneficiary, amount);
  }

  /**
   * @return the balance of an account.
   */
  function balanceOf(address account) public view returns(uint256) {
    return _balances[account];
  }

  /**
   * @dev Overrides parent by storing balances instead of issuing tokens right away.
   * @param beneficiary Token purchaser
   * @param tokenAmount Amount of tokens purchased
   */
  function _processPurchase(
    address beneficiary,
    uint256 tokenAmount
  )
    internal
  {
    _balances[beneficiary] = _balances[beneficiary].add(tokenAmount);
  }

}

// File: openzeppelin-solidity/contracts/crowdsale/distribution/FinalizableCrowdsale.sol

/**
 * @title FinalizableCrowdsale
 * @dev Extension of Crowdsale with a one-off finalization action, where one
 * can do extra work after finishing.
 */
contract FinalizableCrowdsale is TimedCrowdsale {
  using SafeMath for uint256;

  bool private _finalized = false;

  event CrowdsaleFinalized();

  /**
   * @return true if the crowdsale is finalized, false otherwise.
   */
  function finalized() public view returns (bool) {
    return _finalized;
  }

  /**
   * @dev Must be called after crowdsale ends, to do some extra finalization
   * work. Calls the contract's finalization function.
   */
  function finalize() public {
    require(!_finalized);
    require(hasClosed());

    _finalization();
    emit CrowdsaleFinalized();

    _finalized = true;
  }

  /**
   * @dev Can be overridden to add finalization logic. The overriding function
   * should call super._finalization() to ensure the chain of finalization is
   * executed entirely.
   */
  function _finalization() internal {
  }

}

// File: openzeppelin-solidity/contracts/ownership/Ownable.sol

/**
 * @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 private _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;
  }

  /**
   * @return the address of the owner.
   */
  function owner() public view returns(address) {
    return _owner;
  }

  /**
   * @dev Throws if called by any account other than the owner.
   */
  modifier onlyOwner() {
    require(isOwner());
    _;
  }

  /**
   * @return true if `msg.sender` is the owner of the contract.
   */
  function isOwner() public view returns(bool) {
    return 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;
  }
}

// File: contracts/Whitelist.sol

contract Whitelist is Ownable {

  mapping (address => bool) private whitelistedAddresses;

  mapping (address => bool) private admins;

  modifier onlyIfWhitelisted(address _addr) {
    require(whitelistedAddresses[_addr] == true, "Address not on the whitelist!");
    _;
  }

  modifier onlyAdmins() {
    require(admins[msg.sender] == true || isOwner(), "Not an admin!");
    _;
  }

  function addAdmin(address _addr)
    external
    onlyOwner
  {
    admins[_addr] = true;
  }

  function removeAdmin(address _addr)
    external
    onlyOwner
  {
    admins[_addr] = false;
  }

  function isAdmin(address _addr)
    public
    view
    returns(bool)
  {
    return admins[_addr];
  }

  function addAddressToWhitelist(address _addr)
    public
    onlyAdmins
  {
    whitelistedAddresses[_addr] = true;
  }

  function whitelist(address _addr)
    public
    view
    returns(bool)
  {
    return whitelistedAddresses[_addr];
  }

  function addAddressesToWhitelist(address[] _addrs)
    public
    onlyAdmins
  {
    for (uint256 i = 0; i < _addrs.length; i++) {
      addAddressToWhitelist(_addrs[i]);
    }
  }

  function removeAddressFromWhitelist(address _addr)
    public
    onlyAdmins
  {
    whitelistedAddresses[_addr] = false;
  }

  function removeAddressesFromWhitelist(address[] _addrs)
    public
    onlyAdmins
  {
    for (uint256 i = 0; i < _addrs.length; i++) {
      removeAddressFromWhitelist(_addrs[i]);
    }
  }
}

// File: contracts/ClarityCrowdsale.sol

contract ClarityCrowdsale is
  Crowdsale,
  TimedCrowdsale,
  PostDeliveryCrowdsale,
  FinalizableCrowdsale,
  Whitelist
{

  address private advisorWallet; // forward all phase one funds here

  uint256 private phaseOneRate; // rate for phase one

  uint256 private phaseTwoRate; // rate for phase teo

  uint256 private phaseOneTokens = 10000000 * 10**18; // tokens available in phase one

  uint256 private phaseTwoTokens = 30000000 * 10**18; // tokens available in phase two

  mapping  (address => address) referrals; // Keep track of referrals for bonuses

  modifier onlyFounders() {
    require(msg.sender == super.wallet() || isOwner(), "Not a founder!");
    _;
  }

  constructor(
    uint256 _phaseOneRate,
    uint256 _phaseTwoRate,
    address _advisorWallet,
    address _founderWallet,
    uint256 _openingTime,
    uint256 _closingTime,
    IERC20 _token
  )
    Crowdsale(_phaseTwoRate, _founderWallet, _token)
    TimedCrowdsale(_openingTime, _closingTime)
    public
  {
      advisorWallet = _advisorWallet;
      phaseOneRate = _phaseOneRate;
      phaseTwoRate = _phaseTwoRate;
  }

  // overridden from Crowdsale parent contract
  function _getTokenAmount(uint256 weiAmount)
    internal view returns (uint256)
  {
    if (phaseOneTokens > 0) {
      uint256 tokens = weiAmount.mul(phaseOneRate);
      if (tokens > phaseOneTokens) {
        uint256 weiRemaining = tokens.sub(phaseOneTokens).div(phaseOneRate);
        tokens = phaseOneTokens.add(super._getTokenAmount(weiRemaining));
      }
      return tokens;
    }

    return super._getTokenAmount(weiAmount);
  }

  // overridden from Crowdsale parent contract
  function _forwardFunds()
    internal
  {
    uint256 tokens;
    if (phaseOneTokens > 0) {
      tokens = msg.value.mul(phaseOneRate);
      if (tokens > phaseOneTokens) {
        uint256 weiRemaining = tokens.sub(phaseOneTokens).div(phaseOneRate);
        phaseOneTokens = 0;
        advisorWallet.transfer(msg.value.sub(weiRemaining));
        tokens = weiRemaining.mul(phaseTwoRate);
        phaseTwoTokens = phaseTwoTokens.sub(tokens);
        super.wallet().transfer(weiRemaining);
      } else {
        phaseOneTokens = phaseOneTokens.sub(tokens);
        advisorWallet.transfer(msg.value);
      }
      return;
    }

    tokens = msg.value.mul(phaseTwoRate);
    phaseTwoTokens = phaseTwoTokens.sub(tokens);
    super._forwardFunds();
  }

  // overridden from Crowdsale parent contract
  function _preValidatePurchase(
    address beneficiary,
    uint256 weiAmount
  )
    internal
    onlyIfWhitelisted(beneficiary)
  {
    require(tokensLeft() >= _getTokenAmount(weiAmount), "Insufficient number of tokens to complete purchase!");
    super._preValidatePurchase(beneficiary, weiAmount);
  }

  // overridden from Crowdsale parent contract
  function _finalization()
    internal
    onlyFounders
  {
    super.token().safeTransfer(super.wallet(), tokensLeft());
    super._finalization();
  }

  function tokensLeft()
    public
    view
    returns (uint256)
  {
    return phaseOneTokens + phaseTwoTokens;
  }

  function addReferral(address beneficiary, address referrer)
    external
    onlyAdmins
    onlyIfWhitelisted(referrer)
    onlyIfWhitelisted(beneficiary)
  {
    referrals[beneficiary] = referrer;
  }

  // overridden from Crowdsale parent contract
  function _processPurchase(
    address beneficiary,
    uint256 tokenAmount
  )
    internal
  {
    if (referrals[beneficiary] != 0) {
      uint256 tokensAvailable = tokensLeft().sub(tokenAmount);
      uint256 bonus = tokenAmount.mul(15).div(100);
      if (bonus >= tokensAvailable) {
        bonus = tokensAvailable;
        phaseTwoTokens = phaseTwoTokens.sub(tokensAvailable);
      } else {
        phaseTwoTokens = phaseTwoTokens.sub(bonus);
      }

      if (bonus > 0) {
        super._processPurchase(referrals[beneficiary], bonus);
      }
    }

    super._processPurchase(beneficiary, tokenAmount);
  }
}