import org.neo.smartcontract.framework.SmartContract;

import org.neo.smartcontract.framework.services.neo.Storage;

public class Domain extends SmartContract {

public static Object Main(String operation, Object... args){

if (operation == "query") return Query((String) args[0]);

if (operation == "register") return Register((String)args[0], (byte[])args[1]);

if (operation == "transfer") return Transfer((String) args[0], (byte[])args[1]);

if (operation == "delete") return Delete((String) args[0]);

return false;

}

private static byte[] Query(String domain){

return Storage.get(Storage.currentContext(),domain);

}

private static boolean Register(String domain, byte[] owner) {

byte[] value = Storage.get(Storage.currentContext(), domain);

if (value!= null) return false;

Storage.put(Storage.currentContext(),domain,owner);

return true;

}

private static boolean Transfer(String domain, byte[] to)

{

byte[] from = Storage.get(Storage.currentContext(), domain);

if (from == null) return false;

Storage.put(Storage.currentContext(), domain, to);

return true;

}

private static boolean Delete(String domain)

{

byte[] owner = Storage.get(Storage.currentContext(), domain);

if (owner == null) return false;

Storage.delete(Storage.currentContext(), domain);

return true;

}

}