# passerelle - uniform access to multiple data sources and services
# Copyright (C) 2023 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
import subprocess
from unittest import mock

import pytest
from pdfrw import PdfReader

from passerelle.apps.pdf.models import Resource
from tests.utils import generic_endpoint_url, setup_access_rights

with open(os.path.join(os.path.dirname(__file__), 'data', 'minimal.pdf'), 'rb') as fd:
    pdf_content = base64.b64encode(fd.read()).decode()


@pytest.fixture
def pdf(db):
    return setup_access_rights(Resource.objects.create(slug='test'))


@mock.patch('subprocess.check_output')
def test_pdf_assemble(mocked_check_output, app, pdf):
    endpoint = generic_endpoint_url('pdf', 'assemble', slug=pdf.slug)

    payload = {'filename': 'foo.pdf', 'files/0': {'content': pdf_content}}
    resp = app.post_json(endpoint, params=payload, status=200)
    assert resp.headers['content-type'] == 'application/pdf'
    assert resp.headers['content-disposition'] == 'attachment; filename="foo.pdf"'
    assert mocked_check_output.call_count == 1
    pdftk_call = mocked_check_output.call_args.args[0]
    assert len(pdftk_call) == 5
    assert pdftk_call[0] == '/usr/bin/pdftk'
    assert pdftk_call[1].endswith('/pdf-0.pdf')
    assert pdftk_call[2] == 'cat'
    assert pdftk_call[3] == 'output'
    assert pdftk_call[4] == '-'
    assert mocked_check_output.call_args.kwargs['timeout'] == 20

    payload = {
        'filename': 'bar.pdf',
        'files/0': {'content': ''},
        'files/1': {'content': pdf_content},
        'files/2': None,
        'files/3': pdf_content,
        'files/4': '',
    }
    mocked_check_output.reset_mock()
    resp = app.post_json(endpoint, params=payload, status=200)
    assert resp.headers['content-type'] == 'application/pdf'
    assert resp.headers['content-disposition'] == 'attachment; filename="bar.pdf"'
    assert mocked_check_output.call_count == 1
    pdftk_call = mocked_check_output.call_args.args[0]
    assert len(pdftk_call) == 6
    assert pdftk_call[0] == '/usr/bin/pdftk'
    assert pdftk_call[1].endswith('/pdf-1.pdf')  # file 0
    assert pdftk_call[2].endswith('/pdf-3.pdf')  # file 2

    # pdftk errors (faked)
    payload = {'filename': 'out.pdf', 'files/0': {'content': pdf_content}}
    mocked_check_output.reset_mock()
    mocked_check_output.side_effect = subprocess.TimeoutExpired(cmd=[], timeout=20)
    resp = app.post_json(endpoint, params=payload, status=200)
    assert mocked_check_output.call_count == 1
    assert resp.json['err'] == 1
    assert resp.json['err_desc'].startswith('pdftk timed out after 20 seconds')

    mocked_check_output.reset_mock()
    mocked_check_output.side_effect = subprocess.CalledProcessError(cmd=[], returncode=42, output='ooops')
    resp = app.post_json(endpoint, params=payload, status=200)
    assert mocked_check_output.call_count == 1
    assert resp.json['err'] == 1
    assert resp.json['err_desc'].startswith('pdftk returned non-zero exit status 42')
    assert 'ooops' in resp.json['err_desc']

    # bad calls errors
    resp = app.post(endpoint, status=400)
    assert resp.headers['content-type'].startswith('application/json')
    assert resp.json['err'] == 1
    assert resp.json['err_desc'].startswith('could not decode body to json')

    payload = {}
    resp = app.post_json(endpoint, params=payload, status=400)
    assert resp.json['err'] == 1
    assert resp.json['err_desc'] == "'filename' is a required property"

    payload = {'filename': 'out.pdf'}
    resp = app.post_json(endpoint, params=payload, status=400)
    assert resp.json['err'] == 1
    assert resp.json['err_desc'] == "'files' is a required property"

    payload = {'filename': 'out.pdf', 'files/0': 42}
    resp = app.post_json(endpoint, params=payload, status=400)
    assert resp.json['err'] == 1
    assert resp.json['err_desc'] == "42 is not of type 'object'"

    resp = app.get(endpoint, status=405)


def test_pdf_real_pdftk_call(app, pdf, settings):
    if not os.path.exists(settings.PDFTK_PATH):
        pytest.skip('pdftk (%s) not found' % settings.PDFTK_PATH)

    endpoint = generic_endpoint_url('pdf', 'assemble', slug=pdf.slug)
    payload = {
        'filename': 'twopages.pdf',
        'files/0': {'content': pdf_content},
        'files/1': {'content': pdf_content},
    }
    resp = app.post_json(endpoint, params=payload, status=200)
    assert resp.headers['content-type'] == 'application/pdf'
    assert resp.headers['content-disposition'] == 'attachment; filename="twopages.pdf"'
    assert resp.content[:5] == b'%PDF-'
    assert PdfReader(fdata=resp.content).numPages == 2