# Copyright © 2022 Aravinth Manivannan <realaravinth@batsense.net>
#
# 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/>.
from enum import Enum, unique

from git import Repo
from django.contrib.auth.models import User
from django.conf import settings

from .models import Instance, InstanceConfiguration


@unique
class VmErrors(Enum):
    NAME_EXISTS = "Instance name exists, please try again with a different name"
    NO_CONFIG = "Configuration doesn't exist, please try again."

    def __str__(self) -> str:
        return self.name


class VmException(Exception):
    error: str
    code: VmErrors

    def __init__(self, code: VmErrors):
        self.error = str(code)
        self.code = code

    def __str__(self):
        return self.error


def create_instance(vm_name: str, configuration_name: str, user: User) -> Instance:
    """
    Create instance view
    """

    if Instance.objects.filter(name=vm_name).exists():
        raise VmException(code=VmErrors.NAME_EXISTS)

    if not InstanceConfiguration.objects.filter(name=configuration_name).exists():
        raise VmException(code=VmErrors.NO_CONFIG)

    configuration = InstanceConfiguration.objects.get(name=configuration_name)
    instance = Instance(name=vm_name, configuration_id=configuration, owned_by=user)
    instance.save()
    return instance


source_code = None


def footer_ctx():
    global source_code
    if source_code is None:
        source_code = {"text": "Source Code", "link": settings.HOSTEA["SOURCE_CODE"]}
        try:
            r = Repo(".")
            commit = r.head.commit.hexsha
            source_code["text"] = f"v-{commit.hexsha[0:8]}"
        except:
            pass

    return {
        "source_code": source_code,
        "admin_email": settings.HOSTEA["INSTANCE_MAINTAINER_CONTACT"],
    }