#!/usr/bin/env python3

# Contest Management System - http://cms-dev.github.io/
# Copyright © 2018 Stefano Maggiolo <s.maggiolo@gmail.com>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as
# published by the Free Software Foundation, either version 3 of the
# License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

"""A class to update a dump created by CMS.

Used by DumpImporter and DumpUpdater.

This updater updates time and memory limit to enforce the constraint of being
positive or null (for no limit).

"""

import logging


logger = logging.getLogger(__name__)


class Updater:

    def __init__(self, data):
        assert data["_version"] == 31
        self.objs = data

    def run(self):
        for k, v in self.objs.items():
            if k.startswith("_"):
                continue

            if v["_class"] == "Dataset":

                limit = v["time_limit"]
                # Zero explicitly meant no limits.
                if limit == 0.0:
                    limit = None
                # Negative was undefined though.
                if limit is not None and limit <= 0.0:
                    logger.warning("Previous time limit %s was updated, "
                                   "no time limit is enforced now.",
                                   limit)
                    limit = None
                v["time_limit"] = limit

                limit = v["memory_limit"]
                # Zero explicitly meant no limits.
                if limit == 0:
                    limit = None
                # Negative was undefined though.
                if limit is not None and limit <= 0:
                    logger.warning("Previous memory limit %s was updated, "
                                   "no memory limit is enforced now.",
                                   limit)
                    limit = None
                v["memory_limit"] = limit

        return self.objs