#!/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 import schemas
from gns3server.controller import Controller

router = APIRouter()

responses = {
    404: {"model": schemas.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__()