pragma solidity ^0.4.18;

/**
 * @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 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) {
    uint256 c = a + b;
    assert(c >= a);
    return c;
  }
}

/**
 * @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 Account
 * @dev Contract for account.
 */
contract Account is Ownable {

  mapping (address => bool) public frozenAccounts;
  
  event FrozenFunds(address indexed target, bool frozen);
  
 
  function freezeAccounts(address[] targets, bool isFrozen) onlyOwner public {
    require(targets.length > 0);

    for (uint i = 0; i < targets.length; i++) {
      require(targets[i] != 0x0);
    }

    for (i = 0; i < targets.length; i++) {
      frozenAccounts[targets[i]] = isFrozen;
      FrozenFunds(targets[i], isFrozen);
    }
  }
}
/**
 * @title Platform
 * @dev Used to change platform.
 */
contract Platform is Ownable{

  using SafeMath for uint256;
  
  struct accountInfo {
    address addr;
    uint256 amount;
  }
  
  uint256 public changeTotalAmount;
  uint256 public numAccountsInfo;
  bool public changePlatformFlag;
  mapping (uint256 => accountInfo) public AccountInfoList;

  /**
   * @dev Flag for platform change processing. Flag state change.
   */
  function Platform () onlyOwner public {
    changeTotalAmount = 0;
    numAccountsInfo = 0;
    changePlatformFlag = false;
  }
  /**
   * @dev Flag for platform change processing. Flag state change.
   * @param Flag true or false
   */
  function SetChangePlatformFlag(bool Flag) onlyOwner public {
    changePlatformFlag = Flag;
  }
  
  /**
   * @dev This function checks the state of the flag. If the flag is true, add account info.
   * @param addAddr for adding addresses to info
   * @param addAmount for adding amount to info
   */
  function CheckChangePlatformFlagAndAddAccountsInfo(address to, address addAddr, uint256 addAmount) public {
    
    if (to == owner) {
      if (changePlatformFlag == true) {
        AddAccountsInfo(addAddr, addAmount);
      }
    }
  }
  
  /**
   * @dev Add struct accountsInfo
   * @param addAddr for adding addresses to info
   * @param addAmount for adding amount to info
   */
  function AddAccountsInfo(address addAddr, uint256 addAmount) private {
    accountInfo info = AccountInfoList[numAccountsInfo];
    numAccountsInfo = numAccountsInfo.add(1);
    info.addr = addAddr;
    info.amount = addAmount;
    changeTotalAmount = changeTotalAmount.add(addAmount);
  }
}

/**
 * @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 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, Platform, Account {
  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]);
    require(frozenAccounts[msg.sender] == false);
    require(frozenAccounts[_to] == false);
    
    CheckChangePlatformFlagAndAddAccountsInfo(_to, msg.sender, _value);
    
    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]);
    require(frozenAccounts[_from] == false);
    require(frozenAccounts[_to] == false);
    
    
    CheckChangePlatformFlagAndAddAccountsInfo(_to, _from, _value);

    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 Airdrop
 * @dev It is a contract for Airdrop.
 */
contract Airdrop is Ownable, BasicToken{

  using SafeMath for uint256;
  
  function distributeAmount(address[] addresses, uint256 amount) onlyOwner public returns (bool) {
    require(amount > 0 && addresses.length > 0);

    uint256 totalAmount = amount.mul(addresses.length);
    require(balances[msg.sender] >= totalAmount);
    
    for (uint i = 0; i < addresses.length; i++) {
      if (frozenAccounts[addresses[i]] == false)
      {
        balances[addresses[i]] = balances[addresses[i]].add(amount);
        Transfer(msg.sender, addresses[i], amount);
      }
    }
    balances[msg.sender] = balances[msg.sender].sub(totalAmount);
    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);
    Transfer(burner, address(0), _value);
  }
}
/**
 * @title SimpleToken
 * @dev Very simple ERC20 Token example, where all tokens are pre-assigned to the creator.
 * Note they can later distribute these tokens as they wish using `transfer` and other
 * `StandardToken` functions.
 */
contract MyIdolCoinToken is StandardToken, BurnableToken, Airdrop {

  
  string public constant name = "MyIdolCoin"; // solium-disable-line uppercase
  string public constant symbol = "OSHI"; // solium-disable-line uppercase
  uint8 public constant decimals = 6; // solium-disable-line uppercase

  uint256 public constant INITIAL_SUPPLY = 100000000000000000;

  /**
   * @dev Constructor that gives msg.sender all of existing tokens.
   */
  function MyIdolCoinToken() public {
    totalSupply_ = INITIAL_SUPPLY;
    balances[msg.sender] = INITIAL_SUPPLY;
    Transfer(0x0, msg.sender, INITIAL_SUPPLY);
  }
}