import logging
import os
import sqlite3
import time

import misc

class Registry:
    def __init__(self, db_file):
        if not db_file: return
        if not os.path.isfile(db_file):
            self._conn = sqlite3.connect(db_file, check_same_thread=False)
            self._create_db()
        else:
            self._conn = sqlite3.connect(db_file, check_same_thread=False)

    def is_registered(self, name):
        if not self._conn: return False
        c = self._conn.cursor()
        c.execute("SELECT COUNT(*) FROM cache WHERE name=?", (name,))
        return c.fetchone()[0] == 1

    def clean(self):
        if not self._conn: return
        c = self._conn.cursor()
        c.execute("DELETE FROM cache WHERE access_time<?", (int(time.time()) - 604800,))
        self._conn.commit()


    def register(self, name):
        if not self._conn: return
        c = self._conn.cursor()
        c.execute( '''INSERT INTO cache (name, access_time) VALUES (?, ?)''',
                   (name, int(time.time())) )
        self._conn.commit()

    def refresh(self, name):
        if not self._conn: return
        c = self._conn.cursor()
        c.execute( "UPDATE cache SET access_time=? WHERE name=?",
                   (int(time.time()), name) )
        self._conn.commit()

    def _create_db(self):
        c = self._conn.cursor()
        c.execute('''CREATE TABLE cache (name TEXT PRIMARY KEY, access_time INTEGER)''')
        self._conn.commit()