#!/usr/bin/env python2

# Copyright (C) 2019 University of Dundee & Open Microscopy Environment.
# All rights reserved.
#
# 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 2 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, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

from omero.callbacks import CmdCallbackI
from omero.gateway import BlitzGateway
from omero.sys import ParametersI
from omero.cmd import Delete2, Delete2Response

import sys

from time import time

# Fill in administrator login credentials.
conn = BlitzGateway('username', 'password', host='omero.server.host')

# Do not inactivate users who logged out within recent days.
minimum_days = 30 * 6

# -=-=- Users need not adjust code below -=-=-

# Report configuration.

print('Ignoring users who have logged out within the past {} days.'
      .format(minimum_days))

# Obtain gateway connection and query service.

conn.connect()
query_service = conn.getQueryService()


def submit(request, expected):
    # Submit a request and wait for it to complete.
    # Returns with the response only if it was of the given type.
    prx = conn.c.sf.submit(request)
    rsp = CmdCallbackI(conn.c, prx).loop(500, 500)
    if not isinstance(rsp, expected):
        conn._closeSession()
        sys.exit('unexpected response: {}'.format(rsp))
    return rsp


# Determine which users to consider inactivating.

users = {}

for result in query_service.projection(
        ("SELECT child.id, child.omeName FROM GroupExperimenterMap "
         "WHERE parent.name = 'user'"), None):
    user_id = result[0].val
    user_name = result[1].val
    users[user_id] = user_name

for result in query_service.projection(
        "SELECT DISTINCT owner.id FROM Session WHERE closed IS NULL", None):
    user_id = result[0].val
    print('Ignoring "{}" (#{}) who is logged in.'
          .format(users[user_id], user_id))
    del users[user_id]

now = time()

for result in query_service.projection(
        "SELECT owner.id, MAX(closed) FROM Session GROUP BY owner.id", None):
    user_id = result[0].val
    if user_id not in users:
        continue

    if result[1] is None:
        # never logged in
        user_logout = 0
    else:
        # note time in seconds since epoch
        user_logout = result[1].val / 1000

    days = (now - user_logout) / (60 * 60 * 24)
    if (days < minimum_days):
        print('Ignoring "{}" (#{}) who logged in recently.'
              .format(users[user_id], user_id))
        del users[user_id]

if not users:
    print('No users need inactivating.')
    exit()

# Inactivate users.

for id, name in users.items():
    print('Inactivating "{}" (#{}).'.format(name, id))

# Find the IDs of the links that mark the users active.

params = ParametersI()
params.addIds(users.keys())

link_ids = []
for result in query_service.projection(
        ("SELECT id FROM GroupExperimenterMap "
         "WHERE parent.name = 'user' AND child.id IN (:ids)"), params):
    link_ids.append(result[0].val)

if link_ids:
    # Inactivate the users.
    delete = Delete2(targetObjects={'GroupExperimenterMap': link_ids})
    submit(delete, Delete2Response)
else:
    print('No users need inactivating.')

conn._closeSession()