import json
import subprocess
from argparse import ArgumentParser
from typing import Any

import requests
from django.conf import settings
from django.core.management.base import CommandError
from django.utils.crypto import get_random_string

from zerver.lib.management import ZulipBaseCommand, check_config

if settings.DEVELOPMENT:
    SECRETS_FILENAME = "zproject/dev-secrets.conf"
else:
    SECRETS_FILENAME = "/etc/zulip/zulip-secrets.conf"

class Command(ZulipBaseCommand):
    help = """Register a remote Zulip server for push notifications."""

    def add_arguments(self, parser: ArgumentParser) -> None:
        parser.add_argument('--agree_to_terms_of_service',
                            dest='agree_to_terms_of_service',
                            action='store_true',
                            default=False,
                            help="Agree to the Zulipchat Terms of Service: https://zulip.com/terms/.")
        parser.add_argument('--rotate-key',
                            dest="rotate_key",
                            action='store_true',
                            default=False,
                            help="Automatically rotate your server's zulip_org_key")

    def handle(self, **options: Any) -> None:
        if not settings.DEVELOPMENT:
            check_config()

        if not settings.ZULIP_ORG_ID:
            raise CommandError("Missing zulip_org_id; run scripts/setup/generate_secrets.py to generate.")
        if not settings.ZULIP_ORG_KEY:
            raise CommandError("Missing zulip_org_key; run scripts/setup/generate_secrets.py to generate.")
        if settings.PUSH_NOTIFICATION_BOUNCER_URL is None:
            if settings.DEVELOPMENT:
                settings.PUSH_NOTIFICATION_BOUNCER_URL = (settings.EXTERNAL_URI_SCHEME +
                                                          settings.EXTERNAL_HOST)
            else:
                raise CommandError("Please uncomment PUSH_NOTIFICATION_BOUNCER_URL "
                                   "in /etc/zulip/settings.py (remove the '#')")

        request = {
            "zulip_org_id": settings.ZULIP_ORG_ID,
            "zulip_org_key": settings.ZULIP_ORG_KEY,
            "hostname": settings.EXTERNAL_HOST,
            "contact_email": settings.ZULIP_ADMINISTRATOR}
        if options["rotate_key"]:
            request["new_org_key"] = get_random_string(64)

        print("The following data will be submitted to the push notification service:")
        for key in sorted(request.keys()):
            print(f"  {key}: {request[key]}")
        print("")

        if not options['agree_to_terms_of_service'] and not options["rotate_key"]:
            print("To register, you must agree to the Zulipchat Terms of Service: "
                  "https://zulip.com/terms/")
            tos_prompt = input("Do you agree to the Terms of Service? [Y/n] ")
            print("")
            if not (tos_prompt.lower() == 'y' or
                    tos_prompt.lower() == '' or
                    tos_prompt.lower() == 'yes'):
                raise CommandError("Aborting, since Terms of Service have not been accepted.")

        registration_url = settings.PUSH_NOTIFICATION_BOUNCER_URL + "/api/v1/remotes/server/register"
        try:
            response = requests.post(registration_url, params=request)
        except Exception:
            raise CommandError(
                "Network error connecting to push notifications service "
                f"({settings.PUSH_NOTIFICATION_BOUNCER_URL})",
            )
        try:
            response.raise_for_status()
        except Exception:
            content_dict = json.loads(response.content.decode("utf-8"))
            raise CommandError("Error: " + content_dict['msg'])

        if response.json()['created']:
            print("You've successfully registered for the Mobile Push Notification Service!\n"
                  "To finish setup for sending push notifications:")
            print("- Restart the server, using /home/zulip/deployments/current/scripts/restart-server")
            print("- Return to the documentation to learn how to test push notifications")
        else:
            if options["rotate_key"]:
                print(f"Success! Updating {SECRETS_FILENAME} with the new key...")
                subprocess.check_call(["crudini", '--set', SECRETS_FILENAME, "secrets", "zulip_org_key",
                                       request["new_org_key"]])
            print("Mobile Push Notification Service registration successfully updated!")