# -*- coding: utf-8 -*-

"""

readability.auth

~~~~~~~~~~~~~~~~

This module provides the xauth functionality for the Readability

Reader API.

"""

from __future__ import unicode_literals

import logging

try:

from urllib.parse import urlencode

except ImportError:

from urllib import urlencode

try:

from urllib.parse import parse_qs

except ImportError:

from urlparse import parse_qs

import requests

from oauthlib.oauth1 import Client

from readability.clients import DEFAULT_READER_URL_TEMPLATE

from readability.core import required_from_env

logger = logging.getLogger(__name__)

ACCESS_TOKEN_URL = 'oauth/access_token/'

def xauth(base_url_template=DEFAULT_READER_URL_TEMPLATE, **xargs):

"""

Returns an OAuth token tuple that can be used with clients.ReaderClient.

:param base_url_template: Template for generating Readability API urls.

:param consumer_key: Readability consumer key, otherwise read from READABILITY_CONSUMER_KEY.

:param consumer_secret: Readability consumer secret, otherwise read from READABILITY_CONSUMER_SECRET.

:param username: A username, otherwise read from READABILITY_USERNAME.

:param password: A password, otherwise read from READABILITY_PASSWORD.

"""

consumer_key = xargs.get('consumer_key') or required_from_env('READABILITY_CONSUMER_KEY')

consumer_secret = xargs.get('consumer_secret') or required_from_env('READABILITY_CONSUMER_SECRET')

username = xargs.get('username') or required_from_env('READABILITY_USERNAME')

password = xargs.get('password') or required_from_env('READABILITY_PASSWORD')

client = Client(consumer_key, client_secret=consumer_secret, signature_type='BODY')

url = base_url_template.format(ACCESS_TOKEN_URL)

headers = {'Content-Type': 'application/x-www-form-urlencoded'}

params = {

'x_auth_username': username,

'x_auth_password': password,

'x_auth_mode': 'client_auth'

}

uri, headers, body = client.sign(url,

http_method='POST',

body=urlencode(params),

headers=headers)

response = requests.post(uri, data=body)

logger.debug('POST to %s.', uri)

token = parse_qs(response.content)

try:

# The indexes below are a little weird. parse_qs above gives us

# back a dict where each value is a list. We want the first value

# in those lists.

token = (token[b'oauth_token'][0].decode(), token[b'oauth_token_secret'][0].decode())

except KeyError:

raise ValueError('Invalid Credentials.')

return token