# Copyright (C) 2018  Lars Wirzenius
# 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 shutil
import tempfile
import unittest

import muck


class StoreTests(unittest.TestCase):

    def setUp(self):
        self.tempdir = tempfile.mkdtemp()
        self.st = muck.Store(self.tempdir)

    def tearDown(self):
        shutil.rmtree(self.tempdir)

    def test_is_initially_empty(self):
        ms = self.st.get_memory_store()
        self.assertEqual(len(ms), 0)
        self.assertEqual(ms.as_dict(), {})

    def test_creates_resource(self):
        meta = {
            'id': 'id-1',
            'rev': 'rev-1',
        }

        res = {
            'foo': 'bar',
        }

        chg = muck.CreateChange(meta=meta, res=res)
        self.st.change(chg)

        ms = self.st.get_memory_store()
        self.assertEqual(len(ms), 1)
        self.assertEqual(
            ms.as_dict(),
            {
                'id-1': (meta, res),
            })

    def test_wont_create_resource_with_conflicting_id(self):
        meta = {
            'id': 'id-1',
            'rev': 'rev-1',
        }

        res = {
            'foo': 'bar',
        }

        chg = muck.CreateChange(meta=meta, res=res)
        self.st.change(chg)

        ms = self.st.get_memory_store()
        with self.assertRaises(muck.Error):
            ms.change(chg)

    def test_updates_resource(self):
        meta_1 = {
            'id': 'id-1',
            'rev': 'rev-1',
        }

        res_v1 = {
            'foo': 'bar',
        }

        meta_2 = dict(meta_1)
        meta_2['rev'] = 'rev-2'

        res_v2 = dict(res_v1)
        res_v2['foo'] = 'yo'

        create = muck.CreateChange(meta=meta_1, res=res_v1)
        update = muck.UpdateChange(meta=meta_2, res=res_v2)

        self.st.change(create)
        self.st.change(update)

        ms = self.st.get_memory_store()
        self.assertEqual(len(ms), 1)
        self.assertEqual(
            ms.as_dict(),
            {
                'id-1': (meta_2, res_v2),
            })

    def test_refuses_to_update_resource_that_didnt_exist(self):
        meta = {
            'id': 'id-1',
            'rev': 'rev-1',
        }

        res = {
            'foo': 'bar',
        }

        update = muck.UpdateChange(meta=meta, res=res)
        with self.assertRaises(muck.Error):
            self.st.change(update)

    def test_deletes_resource(self):
        meta = {
            'id': 'id-1',
            'rev': 'rev-1',
        }

        res = {
            'foo': 'bar',
        }

        create = muck.CreateChange(meta=meta, res=res)
        delete = muck.DeleteChange(meta=meta)

        self.st.change(create)
        self.st.change(delete)

        ms = self.st.get_memory_store()
        self.assertEqual(len(ms), 0)
        self.assertEqual(ms.as_dict(), {})

    def test_refuses_to_delete_resource_that_doesnt_exist(self):
        meta = {
            'id': 'id-1',
            'rev': 'rev-1',
        }

        delete = muck.DeleteChange(meta=meta)
        with self.assertRaises(muck.Error):
            self.st.change(delete)