#!/usr/bin/env python3

# This file is part of Cockpit.
#
# Copyright (C) 2018 Red Hat, Inc.
#
# Cockpit is free software; you can redistribute it and/or modify it
# under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation; either version 2.1 of the License, or
# (at your option) any later version.
#
# Cockpit 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
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with Cockpit; If not, see <http://www.gnu.org/licenses/>.

MAX_PRIORITY = 9

import argparse
import json
import random
import subprocess
import sys
import time
import logging
import pipes

from task import redhat_network, distributed_queue

logging.basicConfig(level=logging.INFO)

# Returns a command to execute and the delivery tag needed to ack the message
def consume_webhook_queue(channel, amqp):
    # interpret payload
    # call tests-scan or issue-scan appropriately
    method_frame, header_frame, body = channel.basic_get(queue='webhook')
    if not method_frame:
        return None, None

    body = json.loads(body)
    event = body['event']
    request = body['request']
    repo = None
    cmd = None
    if event == 'pull_request':
        pull_request = request['pull_request']
        action = request['action']
        # scan for body changes (edited) and the bots label
        if action == 'labeled' or (action == 'edited' and 'body' in request.get('changes', {})):
            cmd = ['bots/issue-scan', '--issues-data', json.dumps(request), '--amqp', amqp]
        if request['action'] in ['opened', 'synchronize']:
            repo = pull_request['base']['repo']['full_name']
            cmd = ['bots/tests-scan', '--pull-data', json.dumps(request), '--amqp', amqp]
    elif event == 'status':
        repo = request['repository']['full_name']
        sha = request['sha']
        context = pipes.quote(request['context'])
        cmd = ['bots/tests-scan', '--sha', sha, '--amqp', amqp, '--context', context]
    elif event == 'issues':
        action = request['action']
        # scan for opened, body changes (edited), and the bots label
        if action in ['opened', 'labeled'] or (action == 'edited' and 'body' in request.get('changes', {})):
            cmd = ['bots/issue-scan', '--issues-data', json.dumps(request), '--amqp', amqp]
    else:
        logging.error('Unkown event type in the webhook queue')
        return None, None

    # HACK: the cockpit repo itself is treated as a special case in tests-scan, in
    # order to avoid complexity avoid supplying the repo option for now
    if repo and repo != 'cockpit-project/cockpit':
        cmd += ['--repo', repo]
    return cmd, method_frame.delivery_tag

# Returns a command to execute and the delivery tag needed to ack the message
def consume_task_queue(channel, amqp, declare_public_result, declare_rhel_result):
    queue='public'
    if redhat_network():
        # Try the rhel queue if the public queue is empty
        if declare_public_result.method.message_count == 0:
            queue = 'rhel'
            # If both are non-empty, shuffle
        elif declare_rhel_result.method.message_count > 0:
            queue = ['public', 'rhel'][random.randrange(2)]

    method_frame, header_frame, body = channel.basic_get(queue=queue)
    if not method_frame:
        return None, None

    body = json.loads(body)
    return body['command'], method_frame.delivery_tag

# Consume from the webhook queue and republish to the task queue via *-scan
# Consume from the task queue (endpoint)
def main():
    parser = argparse.ArgumentParser(description='Bot: read a single test command from the queue and execute it')
    parser.add_argument('--amqp', default='localhost:5671',
                        help='The host:port of the AMQP server to consume from (default: %(default)s)')
    opts = parser.parse_args()

    with distributed_queue.DistributedQueue(opts.amqp, ['webhook', 'rhel', 'public']) as q:
        channel = q.channel

        cmd, delivery_tag = consume_webhook_queue(channel, opts.amqp)
        if not cmd and delivery_tag:
            logging.info("Webhook message interpretation resulted in nop")
            channel.basic_ack(delivery_tag)
            return 0

        if not cmd:
            cmd, delivery_tag = consume_task_queue(channel, opts.amqp, q.declare_results['public'], q.declare_results['rhel'])
        if not cmd:
            logging.info("All queues are empty")
            return 1

        logging.info("Consuming message with command: {0}\n".format(' '.join(cmd) if type(cmd) is list else cmd))
        p = subprocess.Popen(cmd, shell=type(cmd) is str)
        while p.poll() is None:
            q.connection.process_data_events()
            time.sleep(3)

        channel.basic_ack(delivery_tag)

    return 0

if __name__ == '__main__':
    sys.exit(main())