import cherrypy
import requests
from jinja2 import Environment, FileSystemLoader

env = Environment(loader=FileSystemLoader('templates'))


def get_working_url(primary, fallback, timeout=1):
    try:
        response = requests.get(primary, timeout=timeout)
        if response.status_code == 200:
            return primary
    except requests.RequestException:
        pass
    return fallback


class AcceptInvite(object):

    @cherrypy.expose
    def index(self, remote=None, token=None):
        if not remote:
            raise cherrypy.HTTPError(400, "Missing remote")
        if not token:
            raise cherrypy.HTTPError(400, "Missing token")
        disco_url = get_working_url(f'{remote}/.well-known/ocm',
                                    f'{remote}/ocm-provider')
        try:
            r = requests.get(disco_url)
        except requests.exceptions.ConnectionError:
            tmpl = env.get_template('error.html')
            return tmpl.render(message='Unable to reach OCM provider')
        if r.status_code != 200:
            tmpl = env.get_template('error.html')
            return tmpl.render(message=f'Unable to reach OCM provider: {r.status_code}')

        provider_data = r.json()

        if ('capabilities' not in provider_data) or (
                'inviteAcceptDialog' not in provider_data) or (
                    'capabilities' in provider_data
                    and 'invite' not in provider_data['capabilities']):
            tmpl = env.get_template('error.html')
            return tmpl.render(message='Remote does not support OCM invites')
        redirect_url = f'{provider_data['inviteAcceptDialog']}'
        redirect_url += f'?token={token}&providerDomain={cherrypy.request.base}'

        raise cherrypy.HTTPRedirect(redirect_url)