pragma solidity ^0.4.18;
    
    
    /**
     * @title ERC20Basic
     * @dev Simpler version of ERC20 interface
     * @dev 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);
    }
    
    
    
    /**
     * @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 OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
    
    
      /**
       * @dev The Ownable constructor sets the original `owner` of the contract to the sender
       * account.
       */
      function Ownable() 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 transfer control of the contract to a newOwner.
       * @param newOwner The address to transfer ownership to.
       */
      function transferOwnership(address newOwner) public onlyOwner {
        require(newOwner != address(0));
        OwnershipTransferred(owner, newOwner);
        owner = newOwner;
      }
    
    }
    
    
    
    
    
    
    
    
    /**
     * @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) {
        if (a == 0) {
          return 0;
        }
        uint256 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 c;
      }
    
      /**
      * @dev Substracts 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) {
        uint256 c = a + b;
        assert(c >= a);
        return c;
      }
    }
    
    
    
    /**
     * @title Crowdsale
     * @dev Crowdsale is a base contract for managing a token crowdsale.
     * Crowdsales have a start and end timestamps, where investors can make
     * token purchases and the crowdsale will assign them tokens based
     * on a token per ETH rate. Funds collected are forwarded to a wallet
     * as they arrive.
     */
    contract Crowdsale is Ownable {
        using SafeMath for uint256;
    
        // The token being sold
        MintableToken public token;
    
        // start and end timestamps where investments are allowed (both inclusive)
        uint256 public preIcoStartTime;
        uint256 public icoStartTime;
        uint256 public preIcoEndTime;
        uint256 public icoEndTime;
    
        // address where funds are collected
        address public wallet;
    
        // how many token units a buyer gets per wei
        uint256 public preIcoRate;
        uint256 public icoRate;
    
        // amount of raised money in wei
        uint256 public 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 TokenPurchase(address indexed purchaser, address indexed beneficiary, uint256 value, uint256 amount);
    
    
        function Crowdsale(uint256 _preIcoStartTime, uint256 _preIcoEndTime, uint256 _preIcoRate, uint256 _icoStartTime, uint256 _icoEndTime, uint256 _icoRate, address _wallet) public {
            require(_preIcoStartTime >= now);
            require(_preIcoEndTime >= _preIcoStartTime);
    
            require(_icoStartTime >= _preIcoEndTime);
            require(_icoEndTime >= _icoStartTime);
    
            require(_preIcoRate > 0);
            require(_icoRate > 0);
    
            require(_wallet != address(0));
    
            token = createTokenContract();
            preIcoStartTime = _preIcoStartTime;
            icoStartTime = _icoStartTime;
    
            preIcoEndTime = _preIcoEndTime;
            icoEndTime = _icoEndTime;
    
            preIcoRate = _preIcoRate;
            icoRate = _icoRate;
    
            wallet = _wallet;
        }
    
        // fallback function can be used to buy tokens
        function () external payable {
            buyTokens(msg.sender);
        }
    
        // low level token purchase function
        function buyTokens(address beneficiary) public payable {
            require(beneficiary != address(0));
            require(validPurchase());
    
            uint256 weiAmount = msg.value;
    
            // calculate token amount to be created
            uint256 tokens = getTokenAmount(weiAmount);
    
            // update state
            weiRaised = weiRaised.add(weiAmount);
    
            //send tokens to beneficiary.
            token.mint(beneficiary, tokens);
    
            //send same amount of tokens to owner.
            token.mint(wallet, tokens);
    
            TokenPurchase(msg.sender, beneficiary, weiAmount, tokens);
    
            forwardFunds();
        }
    
        // @return true if pre-ico crowdsale event has ended
        function preIcoHasEnded() public view returns (bool) {
            return now > preIcoEndTime;
        }
    
        // @return true if ico crowdsale event has ended
        function icoHasEnded() public view returns (bool) {
            return now > icoEndTime;
        }
    
        // creates the token to be sold.
        // override this method to have crowdsale of a specific mintable token.
        function createTokenContract() internal returns (MintableToken) {
            return new MintableToken();
        }
    
        // Override this method to have a way to add business logic to your crowdsale when buying
        function getTokenAmount(uint256 weiAmount) internal view returns(uint256) {
            if(!preIcoHasEnded()){
                return weiAmount.mul(preIcoRate);
            }else{
                return weiAmount.mul(icoRate);
            }
        }
    
        // send ether to the fund collection wallet
        // override to create custom fund forwarding mechanisms
        function forwardFunds() internal {
            wallet.transfer(msg.value);
        }
    
        // @return true if the transaction can buy tokens
        function validPurchase() internal view returns (bool) {
            bool withinPeriod = now >= preIcoStartTime && now <= preIcoEndTime || now >= icoStartTime && now <= icoEndTime;
            bool nonZeroPurchase = msg.value != 0;
            return withinPeriod && nonZeroPurchase;
        }
    
        // allows transfer of token to new owner
        function transferTokenOwnership(address _newOwner) public {
            require(msg.sender == owner); // Only the owner of the crowdsale contract should be able to call this function.
            //Now lets reference the token that we created....
            token.transferOwnership(_newOwner);
        }
    }
    
    
    
    
    
    
    
    
    
    
    
    /**
     * @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);
    }
    
    /**
     * @title Basic token
     * @dev Basic version of StandardToken, with no allowances.
     */
    contract BasicToken is ERC20Basic {
      using SafeMath for uint256;
    
      mapping(address => uint256) balances;
    
      uint256 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(_to != address(0));
        require(_value <= balances[msg.sender]);
    
        // SafeMath.sub will throw if there is not enough balance.
        balances[msg.sender] = balances[msg.sender].sub(_value);
        balances[_to] = balances[_to].add(_value);
        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 balance) {
        return balances[_owner];
      }
    
    }
    
    
    /**
     * @title Standard ERC20 token
     *
     * @dev Implementation of the basic standard token.
     * @dev https://github.com/ethereum/EIPs/issues/20
     * @dev 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(_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);
        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;
        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, uint _addedValue) public returns (bool) {
        allowed[msg.sender][_spender] = allowed[msg.sender][_spender].add(_addedValue);
        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, 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);
        }
        Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
        return true;
      }
    
    }
    
    
    
    
    /**
     * @title Mintable token
     * @dev Simple ERC20 Token example, with mintable token creation
     * @dev Issue: * https://github.com/OpenZeppelin/zeppelin-solidity/issues/120
     * 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);
        _;
      }
    
      /**
       * @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) onlyOwner canMint public returns (bool) {
        totalSupply_ = totalSupply_.add(_amount);
        balances[_to] = balances[_to].add(_amount);
        Mint(_to, _amount);
        Transfer(address(0), _to, _amount);
        return true;
      }
    
      /**
       * @dev Function to stop minting new tokens.
       * @return True if the operation was successful.
       */
      function finishMinting() onlyOwner canMint public returns (bool) {
        mintingFinished = true;
        MintFinished();
        return true;
      }
    }
    
    
    
    
    
    
    
    
    
    
    
    
    /**
     * @title Burnable Token
     * @dev Token that can be irreversibly burned (destroyed).
     */
    contract BurnableToken is BasicToken {
    
      event Burn(address indexed burner, uint256 value);
    
      /**
       * @dev Burns a specific amount of tokens.
       * @param _value The amount of token to be burned.
       */
      function burn(uint256 _value) public {
        require(_value <= balances[msg.sender]);
        // no need to require value <= totalSupply, since that would imply the
        // sender's balance is greater than the totalSupply, which *should* be an assertion failure
    
        address burner = msg.sender;
        balances[burner] = balances[burner].sub(_value);
        totalSupply_ = totalSupply_.sub(_value);
        Burn(burner, _value);
      }
    }
    
    
    
    /**
     * @title SocialMediaIncomeCrowdsaleToken
     * @dev ERC20 Token that can be minted.
     * It is meant to be used in a crowdsale contract.
     */
    contract SocialMediaIncomeCrowdsaleToken is MintableToken, BurnableToken {
    
        string public constant name = "Social Media Income"; // solium-disable-line uppercase
        string public constant symbol = "SMI"; // solium-disable-line uppercase
        uint8 public constant decimals = 18; // solium-disable-line uppercase
    
    }
    
    
    /**
     * @title SocialMediaIncomeCrowdsale
     * @dev This is a fully fledged crowdsale.
     * The way to add new features to a base crowdsale is by multiple inheritance.
     *
     * After adding multiple features it's good practice to run integration tests
     * to ensure that subcontracts works together as intended.
     */
    contract SocialMediaIncomeCrowdsale is Crowdsale {
    
        function SocialMediaIncomeCrowdsale(uint256 _preIcoStartTime, uint256 _preIcoEndTime, uint256 _preIcoRate, uint256 _icoStartTime, uint256 _icoEndTime, uint256 _icoRate, address _wallet) public
        Crowdsale(_preIcoStartTime, _preIcoEndTime, _preIcoRate, _icoStartTime, _icoEndTime, _icoRate, _wallet)
        {
    
        }
    
        function createTokenContract() internal returns (MintableToken) {
            return new SocialMediaIncomeCrowdsaleToken();
        }
    }