def __init__(self, dbname):
     self.db_versions = {}
     self.db_name = dbname
     self.my_db = db.DBConnection(self.db_name)
     self.filename = db.dbFilename(self.db_name)
     self.backup_filename = db.dbFilename(self.db_name, 'bak')
     self.rollback_version = None

def backupDatabase(version):
    logger.log(u"Backing up database before upgrade")

    if not helpers.backupVersionedFile(db.dbFilename(), version):
        logger.log_error_and_exit(u"Database backup failed, abort upgrading database")
    else:
        logger.log(u"Proceeding with upgrade")

    def execute(self):

        numTries = 0
        while not ek.ek(os.path.isfile, db.dbFilename(suffix='v0')):
            if not ek.ek(os.path.isfile, db.dbFilename()):
                break

            try:
                logger.log(u"Attempting to back up your sickbeard.db file before migration...")
                shutil.copy(db.dbFilename(), db.dbFilename(suffix='v0'))
                logger.log(u"Done backup, proceeding with migration.")
                break
            except Exception, e:
                logger.log(u"Error while trying to back up your sickbeard.db: "+ex(e))
                numTries += 1
                time.sleep(1)
                logger.log(u"Trying again.")

            if numTries >= 10:
                logger.log(u"Unable to back up your sickbeard.db file, please do it manually.")
                sys.exit(1)

def backupDatabase(version):
    helpers.backupVersionedFile(db.dbFilename(), version)

    def execute(self):
        backupDatabase(0)

        # old stuff that's been removed from common but we need it to upgrade
        HD = 1
        SD = 3
        ANY = 2
        BEST = 4

        ACTION_SNATCHED = 1
        ACTION_PRESNATCHED = 2
        ACTION_DOWNLOADED = 3

        PREDOWNLOADED = 3
        MISSED = 6
        BACKLOG = 7
        DISCBACKLOG = 8
        SNATCHED_BACKLOG = 10

        ### Update default quality
        if sickbeard.QUALITY_DEFAULT == HD:
            sickbeard.QUALITY_DEFAULT = common.HD
        elif sickbeard.QUALITY_DEFAULT == SD:
            sickbeard.QUALITY_DEFAULT = common.SD
        elif sickbeard.QUALITY_DEFAULT == ANY:
            sickbeard.QUALITY_DEFAULT = common.ANY
        elif sickbeard.QUALITY_DEFAULT == BEST:
            sickbeard.QUALITY_DEFAULT = common.BEST

        ### Update episode statuses
        toUpdate = self.connection.select("SELECT episode_id, location, status FROM tv_episodes WHERE status IN (?, ?, ?, ?, ?, ?, ?)", [common.DOWNLOADED, common.SNATCHED, PREDOWNLOADED, MISSED, BACKLOG, DISCBACKLOG, SNATCHED_BACKLOG])
        didUpdate = False
        for curUpdate in toUpdate:

            # remember that we changed something
            didUpdate = True

            newStatus = None
            oldStatus = int(curUpdate["status"])
            if oldStatus == common.SNATCHED:
                newStatus = common.Quality.compositeStatus(common.SNATCHED, common.Quality.UNKNOWN)
            elif oldStatus == PREDOWNLOADED:
                newStatus = common.Quality.compositeStatus(common.DOWNLOADED, common.Quality.SDTV)
            elif oldStatus in (MISSED, BACKLOG, DISCBACKLOG):
                newStatus = common.WANTED
            elif oldStatus == SNATCHED_BACKLOG:
                newStatus = common.Quality.compositeStatus(common.SNATCHED, common.Quality.UNKNOWN)

            if newStatus != None:
                self.connection.action("UPDATE tv_episodes SET status = ? WHERE episode_id = ? ", [newStatus, curUpdate["episode_id"]])
                continue

            # if we get here status should be == DOWNLOADED
            if not curUpdate["location"]:
                continue

            newQuality = common.Quality.nameQuality(curUpdate["location"])

            if newQuality == common.Quality.UNKNOWN:
                newQuality = common.Quality.assumeQuality(curUpdate["location"])

            self.connection.action("UPDATE tv_episodes SET status = ? WHERE episode_id = ?", [common.Quality.compositeStatus(common.DOWNLOADED, newQuality), curUpdate["episode_id"]])

        # if no updates were done then the backup is useless
        if didUpdate:
            os.remove(db.dbFilename(suffix='v0'))

        ### Update show qualities
        toUpdate = self.connection.select("SELECT * FROM tv_shows")
        for curUpdate in toUpdate:

            if not curUpdate["quality"]:
                continue

            if int(curUpdate["quality"]) == HD:
                newQuality = common.HD
            elif int(curUpdate["quality"]) == SD:
                newQuality = common.SD
            elif int(curUpdate["quality"]) == ANY:
                newQuality = common.ANY
            elif int(curUpdate["quality"]) == BEST:
                newQuality = common.BEST
            else:
                logger.log(u"Unknown show quality: " + str(curUpdate["quality"]), logger.WARNING)
                newQuality = None

            if newQuality:
                self.connection.action("UPDATE tv_shows SET quality = ? WHERE show_id = ?", [newQuality, curUpdate["show_id"]])

        ### Update history
        toUpdate = self.connection.select("SELECT * FROM history")
        for curUpdate in toUpdate:

            newAction = None
            newStatus = None
            if int(curUpdate["action"] == ACTION_SNATCHED):
                newStatus = common.SNATCHED
            elif int(curUpdate["action"] == ACTION_DOWNLOADED):
                newStatus = common.DOWNLOADED
            elif int(curUpdate["action"] == ACTION_PRESNATCHED):
#.........这里部分代码省略.........