# -*- Mode:Python; indent-tabs-mode:nil; tab-width:4; encoding:utf-8 -*-
#
# Copyright 2013 J.P. Krauss
#
# This file is part of duplicity.
#
# Duplicity 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 2 of the License, or (at your
# option) any later version.
#
# Duplicity 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 duplicity; if not, write to the Free Software Foundation,
# Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

import os

import duplicity.backend
from duplicity import log
from duplicity import util
from duplicity.errors import BackendException


class PyraxBackend(duplicity.backend.Backend):
    """
    Backend for Rackspace's CloudFiles using Pyrax
    """

    def __init__(self, parsed_url):
        duplicity.backend.Backend.__init__(self, parsed_url)

        try:
            import pyrax
        except ImportError as e:
            raise BackendException(
                f"""Pyrax backend requires the pyrax library available from Rackspace.
Exception: {str(e)}"""
            )

        # Inform Pyrax that we're talking to Rackspace
        # per Jesus Monzon (gsusmonzon)
        pyrax.set_setting("identity_type", "rackspace")

        conn_kwargs = {}

        if "CLOUDFILES_USERNAME" not in os.environ:
            raise BackendException("CLOUDFILES_USERNAME environment variable" "not set.")

        if "CLOUDFILES_APIKEY" not in os.environ:
            raise BackendException("CLOUDFILES_APIKEY environment variable not set.")

        conn_kwargs["username"] = os.environ["CLOUDFILES_USERNAME"]
        conn_kwargs["api_key"] = os.environ["CLOUDFILES_APIKEY"]

        if "CLOUDFILES_REGION" in os.environ:
            conn_kwargs["region"] = os.environ["CLOUDFILES_REGION"]

        container = parsed_url.path.lstrip("/")

        try:
            pyrax.set_credentials(**conn_kwargs)
        except Exception as e:
            log.FatalError(
                f"Connection failed, please check your credentials: {e.__class__.__name__} {util.uexc(e)}",
                log.ErrorCode.connection_failed,
            )

        self.client_exc = pyrax.exceptions.ClientException
        self.nso_exc = pyrax.exceptions.NoSuchObject

        # query rackspace for the specified container name
        try:
            self.container = pyrax.cloudfiles.get_container(container)
        except pyrax.exceptions.Forbidden as e:
            log.FatalError(
                f"{e.__class__.__name__} : {util.uexc(e)} \n"
                + "Container may exist, but access was denied.\n"
                + "If this container exists, please check its X-Container-Read/Write headers.\n"
                + "Otherwise, please check your credentials and permissions.",
                log.ErrorCode.backend_permission_denied,
            )
        except pyrax.exceptions.NoSuchContainer as e:
            try:
                self.container = pyrax.cloudfiles.create_container(container)
            except pyrax.exceptions.Forbidden as e:
                log.FatalError(
                    f"{e.__class__.__name__} : {util.uexc(e)} \n"
                    + "Container does not exist, but creation was denied.\n"
                    + "You may be using a read-only user that can view but not create containers.\n"
                    + "Please check your credentials and permissions.",
                    log.ErrorCode.backend_permission_denied,
                )

    def _error_code(self, operation, e):  # pylint: disable=unused-argument
        if isinstance(e, self.nso_exc):
            return log.ErrorCode.backend_not_found
        elif isinstance(e, self.client_exc):
            if e.code == 404:
                return log.ErrorCode.backend_not_found
        elif hasattr(e, "http_status"):
            if e.http_status == 404:
                return log.ErrorCode.backend_not_found

    def _put(self, source_path, remote_filename):
        self.container.upload_file(source_path.name, remote_filename)

    def _get(self, remote_filename, local_path):
        sobject = self.container.get_object(remote_filename)
        with open(local_path.name, "wb") as f:
            f.write(sobject.get())

    def _list(self):
        # Cloud Files will return a max of 10,000 objects.  We have
        # to make multiple requests to get them all.
        objs = self.container.get_object_names()
        keys = objs
        while len(objs) == 10000:
            objs = self.container.get_object_names(marker=keys[-1])
            keys += objs
        return keys

    def _delete(self, filename):
        self.container.delete_object(filename)

    def _query(self, filename):
        sobject = self.container.get_object(filename)
        return {"size": sobject.total_bytes}
