"""
.. module: lemur.destinations.service
    :platform: Unix
    :copyright: (c) 2018 by Netflix Inc., see AUTHORS for more
    :license: Apache, see LICENSE for more details.
.. moduleauthor:: Kevin Glisson <kglisson@netflix.com>
"""
from sqlalchemy import func

from lemur import database
from lemur.models import certificate_destination_associations
from lemur.destinations.models import Destination
from lemur.certificates.models import Certificate


def create(label, plugin_name, options, description=None):
    """
    Creates a new destination, that can then be used as a destination for certificates.

    :param label: Destination common name
    :param description:
    :rtype : Destination
    :return: New destination
    """
    # remove any sub-plugin objects before try to save the json options
    for option in options:
        if 'plugin' in option['type']:
            del option['value']['plugin_object']

    destination = Destination(label=label, options=options, plugin_name=plugin_name, description=description)
    return database.create(destination)


def update(destination_id, label, options, description):
    """
    Updates an existing destination.

    :param destination_id:  Lemur assigned ID
    :param label: Destination common name
    :param description:
    :rtype : Destination
    :return:
    """
    destination = get(destination_id)

    destination.label = label
    destination.options = options
    destination.description = description

    return database.update(destination)


def delete(destination_id):
    """
    Deletes an destination.

    :param destination_id: Lemur assigned ID
    """
    database.delete(get(destination_id))


def get(destination_id):
    """
    Retrieves an destination by its lemur assigned ID.

    :param destination_id: Lemur assigned ID
    :rtype : Destination
    :return:
    """
    return database.get(Destination, destination_id)


def get_by_label(label):
    """
    Retrieves a destination by its label

    :param label:
    :return:
    """
    return database.get(Destination, label, field='label')


def get_all():
    """
    Retrieves all destination currently known by Lemur.

    :return:
    """
    query = database.session_query(Destination)
    return database.find_all(query, Destination, {}).all()


def render(args):
    filt = args.pop('filter')
    certificate_id = args.pop('certificate_id', None)

    if certificate_id:
        query = database.session_query(Destination).join(Certificate, Destination.certificate)
        query = query.filter(Certificate.id == certificate_id)
    else:
        query = database.session_query(Destination)

    if filt:
        terms = filt.split(';')
        query = database.filter(query, Destination, terms)

    return database.sort_and_page(query, Destination, args)


def stats(**kwargs):
    """
    Helper that defines some useful statistics about destinations.

    :param kwargs:
    :return:
    """
    items = database.db.session.query(Destination.label, func.count(certificate_destination_associations.c.certificate_id))\
        .join(certificate_destination_associations)\
        .group_by(Destination.label).all()

    keys = []
    values = []
    for key, count in items:
        keys.append(key)
        values.append(count)

    return {'labels': keys, 'values': values}