# -*- coding: utf-8 -*-
# passerelle-grandlyon-cartads-cs
# support for Cart@DS CS connector in Grand Lyon environment
# Copyright (C) 2019  Entr'ouvert
#
# This program is free software: you can redistribute it and/or modify it
# under the terms of the GNU Affero General Public License as published
# by the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

import base64
import os

from django.core.cache import cache
from django.db import models
from django.utils.translation import ugettext_lazy as _

from passerelle.apps.cartads_cs.models import AbstractCartaDSCS
from passerelle.utils import SOAPTransport

class Transport(SOAPTransport):
    def post(self, address, message, headers):
        headers['Authorization'] = self.resource.get_api_manager_token()
        response = super(Transport, self).post(address, message, headers)
        if response.status_code == 401:
            # ask for a new token and retry
            headers['Authorization'] = self.resource.get_api_manager_token(renew=True)
            response = super(Transport, self).post(address, message, headers)
        return response


class GLCartaDSCS(AbstractCartaDSCS):
    category = 'Grand Lyon'
    soap_transport_class = Transport

    token_url = models.URLField(_('Token URL'), max_length=256)
    token_authorization = models.CharField(_('Token Authorization'), max_length=128)
    sendfile_ws_url = models.URLField(
            _('Sendfile Webservice URL'),
            max_length=256, blank=True)
    sendfile_ws_dirname = models.CharField(
            _('Sendfile Webservice Directory Name'),
            max_length=256, blank=True)
    verify_cert = models.BooleanField(default=True,
                                      verbose_name=_('Check HTTPS Certificate validity'))

    class Meta:
        verbose_name = 'Cart@DS CS (@ Grand Lyon)'

    def soap_client(self, **kwargs):
        # use original BaseResource soap_client as cart@ds wsdl files cannot be
        # served directly and have to be copied to a different server :/
        return super(AbstractCartaDSCS, self).soap_client(**kwargs)

    def get_api_manager_token(self, renew=False):
        cache_key = 'cartads-%s-token' % self.id
        if not renew:
            token = cache.get(cache_key)
            if token:
                return token
        headers = {'Authorization': 'Basic %s' % self.token_authorization}
        resp = self.requests.post(
                self.token_url,
                headers=headers,
                data={'grant_type': 'client_credentials'},
                verify=self.verify_cert).json()
        token = '%s %s' % (resp.get('token_type'), resp.get('access_token'))
        timeout = int(resp.get('expires_in'))
        cache.set(cache_key, token, timeout)
        self.logger.debug('new token: %s (timeout %ss)', token, timeout)
        return token

    def upload_zip(self, zip_filename):
        b64_zip = base64.b64encode(open(zip_filename).read())
        chunk_size = 16777216  # 16MB
        for n in range(0, len(b64_zip), chunk_size):
            resp = self.requests.post(self.sendfile_ws_url,
                    data={
                        'fileName': self.sendfile_ws_dirname + os.path.basename(zip_filename),
                        'b64_fileContent': b64_zip[n:n+chunk_size],
                    }
                    )
            resp.raise_for_status()