# fargo - document box
# Copyright (C) 2016-2019  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 cgi

from django.utils import six
from django.utils.http import unquote
from django.utils.timezone import now
from django.conf import settings

from .models import OAuth2Authorize


def authenticate_bearer(request):
    authorization = request.META.get('HTTP_AUTHORIZATION')
    if not authorization:
        return False
    splitted = authorization.split()
    if len(splitted) < 2:
        return False
    if splitted[0] != 'Bearer':
        return False
    token = splitted[1]
    try:
        authorize = OAuth2Authorize.objects.get(access_token=token)
        if (now() - authorize.creation_date).total_seconds() > settings.FARGO_ACCESS_TOKEN_LIFETIME:
            return False
        return authorize
    except OAuth2Authorize.DoesNotExist:
        return False


def get_content_disposition_value(request):
    if 'HTTP_CONTENT_DISPOSITION' not in request.META:
        return None, 'missing content-disposition header'
    content_header = request.META['HTTP_CONTENT_DISPOSITION']
    disposition_type, filename = cgi.parse_header(content_header)
    if disposition_type != 'attachment':
        return None, 'wrong disposition type: attachment expected'
    if 'filename*' in filename:
        encode, country, name = filename['filename*'].split("'")
        if six.PY3:
            return (unquote(name, encode), None)
        # check accepted charset from rfc 5987
        if encode == 'UTF-8':
            return unquote(name).decode('utf8'), None
        elif encode == 'ISO-8859-1':
            return unquote(name).decode('iso-8859-1'), None
        else:
            return None, 'unknown encoding: UTF-8 or ISO-8859-1 allowed'
    elif 'filename' in filename:
        return filename['filename'], None
    else:
        # no filename in header
        return None, 'missing filename(*) parameter in header'