pragma solidity >=0.5.0<0.6.0;

//filename: contracts/Consts.sol
contract Consts {
    string constant TOKEN_NAME = "Smathium";
    string constant TOKEN_SYMBOL = "SMT";
    uint8 constant TOKEN_DECIMALS = 18;
    uint256 constant TOKEN_AMOUNT = 10000000000;

    address payable[] SALE_ETH_WALLET = [0x9fBFbBac0f1faF30d01FDc862CB750EbfA1cD61b, 0x9fBFbBac0f1faF30d01FDc862CB750EbfA1cD61b, 0x9fBFbBac0f1faF30d01FDc862CB750EbfA1cD61b, 0x9fBFbBac0f1faF30d01FDc862CB750EbfA1cD61b];
    uint256[] SALE_HARD_CAP = [0, 0, 0, 3000000000];
    uint256[] SALE_SOFT_CAP = [0, 0, 0, 0];
    uint256[] SALE_RATE = [34826, 29915, 25926, 24561];
    uint256[] SALE_OPENING_TIME = [0, 0, 0, 1557068400];
    uint256[] SALE_CLOSING_TIME = [0, 0, 0, 1564412399];
    uint256[] SALE_MIN_ETH = [5 ether, 5 ether, 1 ether, 1 ether];
    uint256[] SALE_MAX_ETH = [500 ether, 500 ether, 500 ether, 500 ether];
}

//filename: contracts/utils/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 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 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));
        emit OwnershipTransferred(owner, newOwner);
        owner = newOwner;
    }

    /**
     * @dev Allows the current owner to relinquish control of the contract.
     */
    function renounceOwnership() public onlyOwner {
        emit OwnershipRenounced(owner);
        owner = address(0);
    }
}

//filename: contracts/tokens/ERC20Basic.sol
/**
 * @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);
}

//filename: contracts/utils/SafeMath.sol
/**
 * @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) {
        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;
    }
}

//filename: contracts/tokens/BasicToken.sol
/**
 * @title Basic tokens
 * @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 tokens 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]);

        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];
    }

}

//filename: contracts/tokens/ERC20.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);
}

//filename: contracts/tokens/StandardToken.sol
/**
 * @title Standard ERC20 tokens
 *
 * @dev Implementation of the basic standard tokens.
 * @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);
        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, 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;
    }

    /**
     * @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);
        }
        emit Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
        return true;
    }
}

//filename: contracts/tokens/TransferableToken.sol
/**
 * @title TransferableToken
 */
contract TransferableToken is StandardToken, Ownable {
    bool public isLock;

    mapping (address => bool) public transferableAddresses;

    constructor() public {
        isLock = true;
        transferableAddresses[msg.sender] = true;
    }

    event Unlock();
    event TransferableAddressAdded(address indexed addr);
    event TransferableAddressRemoved(address indexed addr);

    function unlock() public onlyOwner {
        isLock = false;
        emit Unlock();
    }

    function isTransferable(address addr) public view returns(bool) {
        return !isLock || transferableAddresses[addr];
    }

    function addTransferableAddresses(address[] memory addrs) public onlyOwner returns(bool success) {
        for (uint256 i = 0; i < addrs.length; i++) {
            if (addTransferableAddress(addrs[i])) {
                success = true;
            }
        }
    }

    function addTransferableAddress(address addr) public onlyOwner returns(bool success) {
        if (!transferableAddresses[addr]) {
            transferableAddresses[addr] = true;
            emit TransferableAddressAdded(addr);
            success = true;
        }
    }

    function removeTransferableAddresses(address[] memory addrs) public onlyOwner returns(bool success) {
        for (uint256 i = 0; i < addrs.length; i++) {
            if (removeTransferableAddress(addrs[i])) {
                success = true;
            }
        }
    }

    function removeTransferableAddress(address addr) public onlyOwner returns(bool success) {
        if (transferableAddresses[addr]) {
            transferableAddresses[addr] = false;
            emit TransferableAddressRemoved(addr);
            success = true;
        }
    }

    /**
    */
    function transferFrom(address _from, address _to, uint256 _value) public returns (bool) {
        require(isTransferable(_from));
        return super.transferFrom(_from, _to, _value);
    }

    /**
    */
    function transfer(address _to, uint256 _value) public returns (bool) {
        require(isTransferable(msg.sender));
        return super.transfer(_to, _value);
    }
}

//filename: contracts/utils/Pausable.sol
/**
 * @title Pausable
 * @dev Base contract which allows children to implement an emergency stop mechanism.
 */
contract Pausable is Ownable {
    event Pause();
    event Unpause();

    bool public paused = false;


    /**
     * @dev Modifier to make a function callable only when the contract is not paused.
     */
    modifier whenNotPaused() {
        require(!paused);
        _;
    }

    /**
     * @dev Modifier to makeWhitelist a function callable only when the contract is paused.
     */
    modifier whenPaused() {
        require(paused);
        _;
    }

    /**
     * @dev called by the owner to pause, triggers stopped state
     */
    function pause() onlyOwner whenNotPaused public {
        paused = true;
        emit Pause();
    }

    /**
     * @dev called by the owner to unpause, returns to normal state
     */
    function unpause() onlyOwner whenPaused public {
        paused = false;
        emit Unpause();
    }
}

//filename: contracts/tokens/PausableToken.sol
/**
 * @title Pausable tokens
 * @dev StandardToken modified with pausable transfers.
 **/
contract PausableToken is StandardToken, Pausable {

    function transfer(address _to, uint256 _value) public whenNotPaused returns (bool) {
        return super.transfer(_to, _value);
    }

    function transferFrom(address _from, address _to, uint256 _value) public whenNotPaused returns (bool) {
        return super.transferFrom(_from, _to, _value);
    }

    function approve(address _spender, uint256 _value) public whenNotPaused returns (bool) {
        return super.approve(_spender, _value);
    }

    function increaseApproval(address _spender, uint _addedValue) public whenNotPaused returns (bool success) {
        return super.increaseApproval(_spender, _addedValue);
    }

    function decreaseApproval(address _spender, uint _subtractedValue) public whenNotPaused returns (bool success) {
        return super.decreaseApproval(_spender, _subtractedValue);
    }
}

//filename: contracts/tokens/BurnableToken.sol
/**
 * @title Burnable Token
 * @dev Token that can be irreversibly burned (destroyed).
 */
contract BurnableToken is BasicToken, Pausable {

    event Burn(address indexed burner, uint256 value);

    /**
     * @dev Burns a specific amount of tokens.
     * @param _value The amount of tokens to be burned.
     */
    function burn(uint256 _value) whenNotPaused public {
        _burn(msg.sender, _value);
    }

    function _burn(address _who, uint256 _value) internal {
        require(_value <= balances[_who]);
        // 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

        balances[_who] = balances[_who].sub(_value);
        totalSupply_ = totalSupply_.sub(_value);
        emit Burn(_who, _value);
        emit Transfer(_who, address(0), _value);
    }
}

//filename: contracts/MainToken.sol
/**
 * @title MainToken
 */
contract MainToken is Consts
    
    , TransferableToken
    , PausableToken
    
    , BurnableToken
    {
    string public constant name = TOKEN_NAME; // solium-disable-line uppercase
    string public constant symbol = TOKEN_SYMBOL; // solium-disable-line uppercase
    uint8 public constant decimals = TOKEN_DECIMALS; // solium-disable-line uppercase

    uint256 public constant INITIAL_SUPPLY = TOKEN_AMOUNT * (10 ** uint256(decimals));

    constructor() public {
        totalSupply_ = INITIAL_SUPPLY;
        balances[msg.sender] = INITIAL_SUPPLY;
        emit Transfer(address(0), msg.sender, INITIAL_SUPPLY);
    }
}