import sqlite3
class Database():
    __instance = None

    def __new__(cls, *args, **kwargs):
        if cls.__instance is None:
            cls.__instance = super().__new__(cls)

        return cls.__instance    

    def __init__(self):
        self.conn = sqlite3.connect('users_subscribes.db')
        self.cur = self.conn.cursor()
        self.cur.execute('CREATE TABLE users (id INTEGER, telegram_id NUMERIC, PRIMARY KEY(id))')
        self.cur.execute('CREATE TABLE feeds (id INTEGER, link TEXT, PRIMARY KEY(id))')
        self.cur.execute('CREATE TABLE subscribes (user_id INTEGER, feed_id INTEGER, FOREIGN KEY(user_id) REFERENCES users(id), FOREIGN KEY(feed_id) REFERENCES feeds(id))')
        self.cur.execute('CREATE TABLE feeds_last_items (feed_id INTEGER, link TEXT, title TEXT, description TEXT, date NUMERIC, FOREIGN KEY(feed_id) REFERENCES feeds(id))')    

    def add_rss_feed():
        pass
    
    def delete_rss_feed():
        pass

    def get_feeds():
        pass

    def get_users_subscribes():
        pass

    def get_feed_items():
        pass

    def storing_feed_content():
        pass