pragma solidity ^0.4.17;

contract ERC223 {
    uint public totalSupply;

    // ERC223 functions and events
    function balanceOf(address who) public constant returns (uint);
    function totalSupply() constant public returns (uint256 _supply);
    function transfer(address to, uint value) public returns (bool ok);
    function transfer(address to, uint value, bytes data) public returns (bool ok);
    function transfer(address to, uint value, bytes data, string customFallback) public returns (bool ok);
    event Transfer(address indexed from, address indexed to, uint value, bytes indexed data);

    // ERC223 functions
    function name() constant public returns (string _name);
    function symbol() constant public returns (string _symbol);
    function decimals() constant public returns (uint8 _decimals);

    
    function transferFrom(address _from, address _to, uint256 _value) returns (bool success);
    //function approve(address _spender, uint256 _value) returns (bool success);
   // function allowance(address _owner, address _spender) constant returns (uint256 remaining);
    event Transfer(address indexed _from, address indexed _to, uint256 _value);
   // event Approval(address indexed _owner, address indexed _spender, uint _value);
     event Burn(address indexed from, uint256 value);
}

/**
 * Include SafeMath Lib
 */
contract SafeMath {
    uint256 constant public MAX_UINT256 =
    0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF;

    function safeAdd(uint256 x, uint256 y) constant internal returns (uint256 z) {
        if (x > MAX_UINT256 - y)
            revert();
        return x + y;
    }

    function safeSub(uint256 x, uint256 y) constant internal returns (uint256 z) {
        if (x < y) {
            revert();
        }
        return x - y;
    }

    function safeMul(uint256 x, uint256 y) constant internal returns (uint256 z) {
        if (y == 0) {
            return 0;
        }
        if (x > MAX_UINT256 / y) {
            revert();
        }
        return x * y;
    }
}

/*
 * Contract that is working with ERC223 tokens
 */
 contract ContractReceiver {

    struct TKN {
        address sender;
        uint value;
        bytes data;
        bytes4 sig;
    }

    function tokenFallback(address _from, uint _value, bytes _data) public {
      TKN memory tkn;
      tkn.sender = _from;
      tkn.value = _value;
      tkn.data = _data;
      uint32 u = uint32(_data[3]) + (uint32(_data[2]) << 8) + (uint32(_data[1]) << 16) + (uint32(_data[0]) << 24);
      tkn.sig = bytes4(u);

      /* tkn variable is analogue of msg variable of Ether transaction
      *  tkn.sender is person who initiated this token transaction   (analogue of msg.sender)
      *  tkn.value the number of tokens that were sent   (analogue of msg.value)
      *  tkn.data is data of token transaction   (analogue of msg.data)
      *  tkn.sig is 4 bytes signature of function
      *  if data of token transaction is a function execution
      */
    }
}

/*
 * CHN token with ERC223 Extensions
 */
contract CHN is ERC223, SafeMath {

    string public name = "Colan Coin";

    string public symbol = "Colan";

    uint8 public decimals = 8;

    uint256 public totalSupply = 10000000000 * 10**8;

    address public owner;
    address public admin;

  //  bool public unlocked = false;

    bool public tokenCreated = false;

    mapping(address => uint256) balances;

    mapping(address => mapping (address => uint256)) allowed;
    
    function admined(){
   admin = msg.sender;
  }
  

    // Initialize to have owner have 100,000,000,000 CHN on contract creation
    // Constructor is called only once and can not be called again (Ethereum Solidity specification)
    function CHN() public {

      
        // Ensure token gets created once only
        require(tokenCreated == false);
        tokenCreated = true;

        owner = msg.sender;
        balances[owner] = totalSupply;

        // Final sanity check to ensure owner balance is greater than zero
        require(balances[owner] > 0);
    }

    modifier onlyOwner() {
        require(msg.sender == owner);
        _;
    }
     modifier onlyAdmin(){
    require(msg.sender == admin) ;
    _;
  }
  function transferAdminship(address newAdmin) onlyAdmin {
     
    admin = newAdmin;
  }
  
  

    // Function to distribute tokens to list of addresses by the provided amount
    // Verify and require that:
    // - Balance of owner cannot be negative
    // - All transfers can be fulfilled with remaining owner balance
    // - No new tokens can ever be minted except originally created 100,000,000,000
    function distributeAirdrop(address[] addresses, uint256 amount) onlyOwner public {
        // Only allow undrop while token is locked
        // After token is unlocked, this method becomes permanently disabled
        //require(unlocked);

        // Amount is in Wei, convert to CHN amount in 8 decimal places
        uint256 normalizedAmount = amount * 10**8;
        // Only proceed if there are enough tokens to be distributed to all addresses
        // Never allow balance of owner to become negative
        require(balances[owner] >= safeMul(addresses.length, normalizedAmount));
        for (uint i = 0; i < addresses.length; i++) {
            balances[owner] = safeSub(balanceOf(owner), normalizedAmount);
            balances[addresses[i]] = safeAdd(balanceOf(addresses[i]), normalizedAmount);
            Transfer(owner, addresses[i], normalizedAmount);
        }
    }

    // Function to access name of token .sha
    function name() constant public returns (string _name) {
        return name;
    }
    // Function to access symbol of token .
    function symbol() constant public returns (string _symbol) {
        return symbol;
    }
    // Function to access decimals of token .
    function decimals() constant public returns (uint8 _decimals) {
        return decimals;
    }
    // Function to access total supply of tokens .
    function totalSupply() constant public returns (uint256 _totalSupply) {
        return totalSupply;
    }

    // Function that is called when a user or another contract wants to transfer funds .
    function transfer(address _to, uint _value, bytes _data, string _custom_fallback) public returns (bool success) {

        // Only allow transfer once unlocked
        // Once it is unlocked, it is unlocked forever and no one can lock again
       // require(unlocked);

        if (isContract(_to)) {
            if (balanceOf(msg.sender) < _value) {
                revert();
            }
            balances[msg.sender] = safeSub(balanceOf(msg.sender), _value);
            balances[_to] = safeAdd(balanceOf(_to), _value);
            ContractReceiver receiver = ContractReceiver(_to);
            receiver.call.value(0)(bytes4(sha3(_custom_fallback)), msg.sender, _value, _data);
            Transfer(msg.sender, _to, _value, _data);
            return true;
        } else {
            return transferToAddress(_to, _value, _data);
        }
    }

    // Function that is called when a user or another contract wants to transfer funds .
    function transfer(address _to, uint _value, bytes _data) public  returns (bool success) {

        // Only allow transfer once unlocked
        // Once it is unlocked, it is unlocked forever and no one can lock again
       // require(unlocked);

        if (isContract(_to)) {
            return transferToContract(_to, _value, _data);
        } else {
            return transferToAddress(_to, _value, _data);
        }
    }
    

    // Standard function transfer similar to ERC223 transfer with no _data .
    // Added due to backwards compatibility reasons .
    function transfer(address _to, uint _value) public returns (bool success) {

        // Only allow transfer once unlocked
        // Once it is unlocked, it is unlocked forever and no one can lock again
        //require(unlocked);

        //standard function transfer similar to ERC223 transfer with no _data
        //added due to backwards compatibility reasons
        bytes memory empty;
        if (isContract(_to)) {
            return transferToContract(_to, _value, empty);
        } else {
            return transferToAddress(_to, _value, empty);
        }
    }

    // assemble the given address bytecode. If bytecode exists then the _addr is a contract.
    function isContract(address _addr) private returns (bool is_contract) {
        uint length;
        assembly {
            //retrieve the size of the code on target address, this needs assembly
            length := extcodesize(_addr)
        }
        return (length > 0);
    }

    // function that is called when transaction target is an address
    function transferToAddress(address _to, uint _value, bytes _data) private returns (bool success) {
        if (balanceOf(msg.sender) < _value) {
            revert();
        }
        balances[msg.sender] = safeSub(balanceOf(msg.sender), _value);
        balances[_to] = safeAdd(balanceOf(_to), _value);
        Transfer(msg.sender, _to, _value, _data);
        return true;
    }
    

    // function that is called when transaction target is a contract
    function transferToContract(address _to, uint _value, bytes _data) private returns (bool success) {
        if (balanceOf(msg.sender) < _value) {
            revert();
        }
        balances[msg.sender] = safeSub(balanceOf(msg.sender), _value);
        balances[_to] = safeAdd(balanceOf(_to), _value);
        ContractReceiver receiver = ContractReceiver(_to);
        receiver.tokenFallback(msg.sender, _value, _data);
        Transfer(msg.sender, _to, _value, _data);
        return true;
    }

    // Get balance of the address provided
    function balanceOf(address _owner) constant public returns (uint256 balance) {
        return balances[_owner];
    }

     // Creator/Owner can unlocked it once and it can never be locked again
     // Use after airdrop is complete
   /* function unlockForever() onlyOwner public {
        unlocked = true;
    }*/

    // Allow transfers if the owner provided an allowance
    // Prevent from any transfers if token is not yet unlocked
    // Use SafeMath for the main logic
    function transferFrom(address _from, address _to, uint256 _value) public returns (bool success) {
        // Only allow transfer once unlocked
        // Once it is unlocked, it is unlocked forever and no one can lock again
        //require(unlocked);
        // Protect against wrapping uints.
        require(balances[_from] >= _value && allowed[_from][msg.sender] >= _value && balances[_to] + _value > balances[_to]);
        uint256 allowance = allowed[_from][msg.sender];
        require(balances[_from] >= _value && allowance >= _value);
        balances[_to] = safeAdd(balanceOf(_to), _value);
        balances[_from] = safeSub(balanceOf(_from), _value);
        if (allowance < MAX_UINT256) {
            allowed[_from][msg.sender] = safeSub(allowed[_from][msg.sender], _value);
        }
        Transfer(_from, _to, _value);
        return true;
    }
    function mintToken(address target, uint256 mintedAmount) onlyOwner{
    balances[target] += mintedAmount;
    totalSupply += mintedAmount;
    Transfer(0, this, mintedAmount);
    Transfer(this, target, mintedAmount);
  }
  
  function burn(uint256 _value) public returns (bool success) {
        require(balances[msg.sender] >= _value);   
        balances[msg.sender] -= _value;            
        totalSupply -= _value;                      
        Burn(msg.sender, _value);
        return true;
    }

 
}