#!/usr/bin/env python3

# Copyright (C) 2020 Apple Inc. All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1.  Redistributions of source code must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
# 2.  Redistributions in binary form must reproduce the above copyright
#    notice, this list of conditions and the following disclaimer in the
#    documentation and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND ANY
# EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
# DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY
# DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
# LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
# ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

import argparse
import json
import math
import os
import subprocess
import sys
import time

import reporelaypy
import webkitcorepy

scripts = os.path.dirname(os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
if os.path.isdir(os.path.join(scripts, 'webkitpy')):
    sys.path.insert(0, scripts)
    import webkitpy

from reporelaypy import Checkout, Database, HookProcessor, HookReceiver, Redirector
from webkitcorepy import arguments, AutoInstall
from whichcraft import which


def main(args=None):
    parser = argparse.ArgumentParser(description='Run a git relay server for testing')

    group = parser.add_argument_group('Repository')
    group.add_argument(
        '--path', '-p', '-C',
        dest='path', default=os.getcwd(), action='store',
        help='Set the repository path to be used',
    )
    group.add_argument(
        '--http-proxy', dest='http_proxy', default=None, action='store',
        help='Set an http proxy',
    )
    group.add_argument(
        '--url', dest='url', default=None, action='store',
        help='Set the repository path to be used',
    )
    parser.add_argument(
        '--sentinal', '--no-sentinal', action=arguments.NoAction, dest='sentinal', default=False,
        help='Lay down sentinal file on disk to determine checkout state.',
    )
    group.add_argument(
        '--update', dest='update_interval', default=0, action='store', type=int,
        help='Set the number of seconds to wait between polling git checkout',
    )
    group.add_argument(
        '--fallback', dest='fallback', default=None, action='store', type=str,
        help='Fallback repository URL',
    )
    group.add_argument(
        '--remote', dest='remotes', action='append',
        help="Add an additional remote to forward changes to, formatted as 'name:url'",
    )

    group = parser.add_argument_group('Database')
    group.add_argument(
        '--redis-host', dest='redis_host', default=None, action='store',
        help="Set the hostname of the Redis database to be used. (Environment variable '{}' used by default)".format(Database.HOST_ENV),
    )
    group.add_argument(
        '--redis-password', dest='redis_password', default=None, action='store',
        help="Set the password of the Redis database to be used. (Environment variable '{}' used by default)".format(Database.PASSWORD_ENV),
    )
    group.add_argument(
        '--redis-expiration', dest='redis_expiration', default=Database.DEFAULT_EXPIRATION, action='store', type=int,
        help="Set the default Redis expiration time in seconds",
    )

    group = parser.add_argument_group('Webserver')
    group.add_argument(
        '--port', dest='port', default=5000, action='store',
        help='Port to expose webserver on.',
    )
    group.add_argument(
        '--poll', dest='poll', default=10, action='store',
        help='Number of seconds between polls of the webserver process.',
    )
    group.add_argument(
        '--redirector', '-r', dest='redirector', action='append',
        help='Base URL to redirect user to for commit information.',
    )

    group = parser.add_argument_group('Hooks')
    group.add_argument(
        '--hooks', '--no-hooks', action=arguments.NoAction, dest='hooks', default=False,
        help='Enable or disable hook end-points (disabled by default)',
    )
    group.add_argument(
        '--debug', '--no-debug', action=arguments.NoAction, dest='hooks_debug', default=True,
        help='Enable endpoint to report hooks being processed (enabled by default)',
    )

    args = parser.parse_args(args=args)

    database = Database(host=args.redis_host, password=args.redis_password)
    print('Constructed database with parameters:')
    print('    Host: {}'.format(database.host or 'None (in-memory fake database)'))
    if database.password:
        print('    Password: {}'.format(len(database.password) * '*'))
    if database.default_expiration:
        print('    Expiration: {} hours'.format(database.default_expiration / (60.0 * 60.0)))
    print('Connecting to database...')
    database.ping()
    print('Connected to database!')

    remotes = {}
    for pair in args.remotes:
        name, remote = pair.split(':', 1)
        if not remote:
            sys.stderr("Invalid forwarding remote '{}'".format(pair))
            return 1
        remotes[name] = remote

    print('Finding checkout...')
    checkout = Checkout(
        path=args.path,
        url=args.url,
        http_proxy=args.http_proxy,
        sentinal=args.sentinal,
        fallback_url=args.fallback,
        remotes=remotes,
    )
    print('Git checkout:')
    print('    Path: {}'.format(checkout.path))
    print('    URL: {}'.format(checkout.url))
    if checkout.fallback_repository:
        print('    Fallback: {}'.format(checkout.fallback_repository.url))
    if not checkout.repository:
        print('    Cloning repository...')

    if args.update_interval:
        print('    Polling checkout with interval of {} seconds, doing first poll now...'.format(args.update_interval))
        checkout.update_all()
    if remotes:
        print('Forwarding updates to:')
        for name, url in remotes.items():
            print('    {}: {}'.format(name, url))

    if args.redirector:
        print('User specified the following redirect urls:')
        for url in args.redirector:
            redirector = Redirector(url)
            print('    {}: {}'.format(redirector.name, redirector.url))

    passenv = dict(
        PYTHONPATH=':'.join(sys.path),
        CHECKOUT=json.dumps(checkout, cls=Checkout.Encoder),
        REDIRECTORS=json.dumps([Redirector(url) for url in args.redirector or []], cls=Redirector.Encoder),
        HOOKS=json.dumps({'enabled': args.hooks, 'debug': args.hooks_debug}),
    )

    if AutoInstall.directory:
        passenv['AUTOINSTALL_PATH'] = AutoInstall.directory
    if database.host:
        passenv[database.HOST_ENV] = database.host
    if database.password:
        passenv[database.PASSWORD_ENV] = database.password
    if database.default_expiration:
        passenv[database.EXPIRATION_ENV] = str(database.default_expiration)
    if os.environ.get(HookReceiver.SECRET_ENV):
        passenv[HookReceiver.SECRET_ENV] = os.environ.get(HookReceiver.SECRET_ENV)

    processor = HookProcessor(checkout=checkout, database=database) if args.hooks else None

    with subprocess.Popen(
        [which('gunicorn'), 'reporelaypy.webserver:app'],
        cwd=os.path.dirname(os.path.dirname(reporelaypy.__file__)),
        env=passenv,
    ) as webserver:
        last_poll = time.time()
        last_pull = time.time()

        while True:
            if last_poll + args.poll < time.time():
                if webserver.poll() is None:
                    break
                last_poll = time.time()
            if last_pull + args.update_interval < time.time():
                processor.process_hooks() if processor else checkout.update_all()
                last_pull = time.time()
            time.sleep(math.gcd(args.poll, args.update_interval))

    return 0


if '__main__' == __name__:
    sys.exit(main(args=sys.argv[1:]))