# -*- coding: utf-8 -*-
# Authors: Cedric Bosdonnat <cbosdonnat@suse.com>
#
# Copyright (C) 2017 SUSE, Inc.
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU 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 General Public License for more details.

# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

"""
FileSource aim is to extract root filesystem from tar archive to destination
directory or qcow2 image.
"""

import os
import logging

from virtBootstrap import utils


# pylint: disable=invalid-name
# Create logger
logger = logging.getLogger(__name__)


class FileSource(object):
    """
    Extract root filesystem from file.
    """
    def __init__(self, **kwargs):
        """
        Bootstrap root filesystem from tarball

        @param uri: Path to tar archive file.
        @param fmt: Format used to store image [dir, qcow2]
        @param uid_map: Mappings for UID of files in rootfs
        @param gid_map: Mappings for GID of files in rootfs
        @param root_password: Root password to set in rootfs
        @param progress: Instance of the progress module
        """
        self.path = kwargs['uri'].path
        self.output_format = kwargs.get('fmt', utils.DEFAULT_OUTPUT_FORMAT)
        self.uid_map = kwargs.get('uid_map', [])
        self.gid_map = kwargs.get('gid_map', [])
        self.root_password = kwargs.get('root_password', None)
        self.progress = kwargs['progress'].update_progress

    def unpack(self, dest):
        """
        Safely extract root filesystem from tarball

        @param dest: Directory path where the files to be extraced
        """

        if not os.path.isfile(self.path):
            raise Exception('Invalid file source "%s"' % self.path)

        layer = [[self.path, os.path.getsize(self.path)]]
        if self.output_format == 'dir':
            self.progress("Extracting files into destination directory",
                          value=0, logger=logger)
            utils.untar_layers(layer, dest, self.progress)

        elif self.output_format == 'qcow2':
            self.progress("Extracting files into qcow2 image", value=0,
                          logger=logger)

            img = utils.BuildImage(
                layers=layer,
                dest=dest,
                progress=self.progress
            )
            img.create_base_layer()
            img.set_root_password(self.root_password)
            if self.uid_map or self.gid_map:
                logger.info("Mapping UID/GID")
                utils.map_id_in_image(
                    1,  # Number of layers
                    dest,
                    self.uid_map,
                    self.gid_map,
                    (self.root_password is None)  # Create new disk?
                )

        else:
            raise Exception("Unknown format:" + self.output_format)

        self.progress("Extraction completed successfully!", value=100,
                      logger=logger)
        logger.info("Files are stored in: " + dest)