#!/usr/bin/env python
#
# Copyright (C) 2016 GNS3 Technologies 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/>.

"""
API endpoints for snapshots.
"""

import logging
log = logging.getLogger()

from fastapi import APIRouter, Depends, status
from typing import List
from uuid import UUID

from gns3server.controller.project import Project
from gns3server.endpoints.schemas.common import ErrorMessage
from gns3server.endpoints import schemas
from gns3server.controller import Controller

router = APIRouter()

responses = {
    404: {"model": ErrorMessage, "description": "Could not find project or snapshot"}
}


def dep_project(project_id: UUID):
    """
    Dependency to retrieve a project.
    """

    project = Controller.instance().get_project(str(project_id))
    return project


@router.post("",
             status_code=status.HTTP_201_CREATED,
             response_model=schemas.Snapshot,
             responses=responses)
async def create_snapshot(snapshot_data: schemas.SnapshotCreate, project: Project = Depends(dep_project)):
    """
    Create a new snapshot of a project.
    """

    snapshot = await project.snapshot(snapshot_data.name)
    return snapshot.__json__()


@router.get("",
            response_model=List[schemas.Snapshot],
            response_model_exclude_unset=True,
            responses=responses)
def get_snapshots(project: Project = Depends(dep_project)):
    """
    Return all snapshots belonging to a given project.
    """

    snapshots = [s for s in project.snapshots.values()]
    return [s.__json__() for s in sorted(snapshots, key=lambda s: (s.created_at, s.name))]


@router.delete("/{snapshot_id}",
               status_code=status.HTTP_204_NO_CONTENT,
               responses=responses)
async def delete_snapshot(snapshot_id: UUID, project: Project = Depends(dep_project)):
    """
    Delete a snapshot.
    """

    await project.delete_snapshot(str(snapshot_id))


@router.post("/{snapshot_id}/restore",
             status_code=status.HTTP_201_CREATED,
             response_model=schemas.Project,
             responses=responses)
async def restore_snapshot(snapshot_id: UUID, project: Project = Depends(dep_project)):
    """
    Restore a snapshot.
    """

    snapshot = project.get_snapshot(str(snapshot_id))
    project = await snapshot.restore()
    return project.__json__()