import requests
from requests.auth import HTTPBasicAuth
from zope import component
from zope.interface import implementer

from ceo_common.errors import UserAlreadySubscribedError, UserNotSubscribedError, \
    NoSuchListError
from ceo_common.interfaces import IMailmanService, IConfig


@implementer(IMailmanService)
class MailmanService:
    def __init__(self):
        cfg = component.getUtility(IConfig)
        self.base_domain = cfg.get('base_domain')
        self.api_base_url = cfg.get('mailman3_api_base_url').rstrip('/')
        api_username = cfg.get('mailman3_api_username')
        api_password = cfg.get('mailman3_api_password')
        self.basic_auth = HTTPBasicAuth(api_username, api_password)

    def subscribe(self, address: str, mailing_list: str):
        if '@' in mailing_list:
            mailing_list = mailing_list[:mailing_list.index('@')]
        if '@' not in address:
            address = f'{address}@{self.base_domain}'
        url = f'{self.api_base_url}/members'
        resp = requests.post(
            url,
            data={
                'list_id': f'{mailing_list}.{self.base_domain}',
                'subscriber': address,
                'pre_verified': 'True',
                'pre_confirmed': 'True',
                'pre_approved': 'True',
            },
            auth=self.basic_auth,
        )
        if not resp.ok:
            desc = resp.json().get('description')
            if resp.status_code == 409:
                raise UserAlreadySubscribedError()
            elif resp.status_code == 400 and desc == 'No such list':
                raise NoSuchListError()
            raise Exception(desc)

    def unsubscribe(self, address: str, mailing_list: str):
        if '@' not in mailing_list:
            mailing_list = f'{mailing_list}@{self.base_domain}'
        if '@' not in address:
            address = f'{address}@{self.base_domain}'
        url = f'{self.api_base_url}/lists/{mailing_list}/member/{address}'
        resp = requests.delete(
            url,
            data={
                'pre_approved': 'True',
                'pre_confirmed': 'True',
            },
            auth=self.basic_auth,
        )
        if not resp.ok:
            desc = resp.json().get('description')
            if resp.status_code == 404:
                # Unfortunately, a 404 here could mean either the list doesn't
                # exist, or the member isn't subscribed
                raise UserNotSubscribedError()
            raise Exception(desc)