public class WordsRepositoryImpl implements Repository, Repository.Splash, SugarTransactionHelper.Callback{

    private Context context;
    private List<WordModel> allWords;
    private List<WordModel> createdDB;

    public WordsRepositoryImpl(Context context){
        this.context = context;
    }
    @Override
    public WordModel getModel(int category, int difficulty, String locale) {
        if(locale.contains("россия") || locale.contains("укра")){
            locale = "ru_UA";
        }else locale="en_EN";
        List<WordModel> tmp;
        do {
            tmp = Select.from(WordModel.class)
                    .where(Condition.prop("diff_id").eq(difficulty),
                            Condition.prop("category_id").eq(category),
                            Condition.prop("locale").eq(locale)).list();
            difficulty++;
        }while (tmp.isEmpty());

        return tmp.get(new Random().nextInt(tmp.size()));
    }

    @Override
    public boolean isDBExist() {
        allWords = WordModel.listAll(WordModel.class);
        if(allWords.isEmpty())
        return false;
        else return true;
    }

    @Override
    public int createDB() {
        for(int i=1; i<=10; i++){
            InputStream ins = context.getResources().openRawResource(
                    context.getResources().getIdentifier("words_"+i+"_hm",
                            "raw", context.getPackageName()));

                String json = readFromRaw(ins);
            Gson gson = new Gson();
            Type listType = new TypeToken<List<WordModel>>() {}.getType();
            createdDB = gson.fromJson(json,listType);
            Log.d("MyLogs", "model count = "+ createdDB.size());
                        Log.d("MyLogs", json);
            SugarRecord.saveInTx(createdDB);
            ins = context.getResources().openRawResource(
                    context.getResources().getIdentifier("words_" + i + "_hm_en",
                            "raw", context.getPackageName()));

             json = readFromRaw(ins);
             gson = new Gson();
             listType = new TypeToken<List<WordModel>>() {}.getType();
            createdDB = gson.fromJson(json,listType);
            Log.d("MyLogs", "model count = "+ createdDB.size());
            Log.d("MyLogs", json);
            SugarRecord.saveInTx(createdDB);

        }
        return 0;
    }

    @Override
    public void manipulateInTransaction() {

    }
    private String readFromRaw(InputStream inputStream){
        BufferedReader is = null;
            is = new BufferedReader(new InputStreamReader(inputStream));

        StringBuilder sb = new StringBuilder();
        try {
            String line;
            while ((line = is.readLine()) != null) {
                sb.append(line);
            }

            inputStream.reset();
        } catch (IOException e) {
            e.printStackTrace();
        }

        return sb.toString();
    }
}

//interface for reposytory above

public interface Repository {
     interface Splash{
         boolean isDBExist();
         int createDB();
    }
    WordModel getModel(int difficulty, int category, String locale);
}