"""
Update task tests.
"""


#
# Fimfarchive, preserves stories from Fimfiction.
# Copyright (C) 2015  Joakim Soderlund
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU 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 General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#


from unittest.mock import MagicMock, call, patch

import pytest

from fimfarchive.exceptions import InvalidStoryError, StorySourceError
from fimfarchive.fetchers import Fetcher
from fimfarchive.flavors import DataFormat, UpdateStatus
from fimfarchive.stories import Story
from fimfarchive.tasks.update import (
    UpdateTask, SUCCESS_DELAY, SKIPPED_DELAY, FAILURE_DELAY,
)


class DummyFetcher(Fetcher):
    """
    Fetcher with local instance storage.
    """

    def __init__(self):
        """
        Constructor.
        """
        self.stories = dict()

    def add(self, key, date, flavors=()):
        """
        Adds a story to the fetcher.
        """
        story = Story(
            key=key,
            flavors=flavors,
            data=f'Story {key}',
            meta={
                'id': key,
                'date_modified': date,
                'chapters': [
                    {'id': key},
                ],
            },
        )

        self.stories[key] = story

        return story

    def fetch(self, key):
        """
        Returns a previously stored story.
        """
        try:
            return self.stories[key]
        except KeyError:
            raise InvalidStoryError()


class TestUpdateTask:
    """
    Tests update task.
    """

    @pytest.fixture
    def fimfiction(self):
        """
        Returns a `Fetcher` simulating Fimfiction.
        """
        return DummyFetcher()

    @pytest.fixture
    def fimfarchive(self):
        """
        Returns a `Fetcher` simulating Fimfarchive.
        """
        return DummyFetcher()

    @pytest.fixture
    def task(self, fimfarchive, fimfiction, tmpdir):
        """
        Returns an `UpdateTask` instance.
        """
        return UpdateTask(
            fimfiction=fimfiction,
            fimfarchive=fimfarchive,
            workdir=str(tmpdir),
            retries=2,
            skips=2,
        )

    def verify_run(self, task, delays):
        """
        Runs the task and verifies delays.
        """
        calls = [call(delay) for delay in delays]

        with patch('time.sleep') as m:
            task.run()
            m.assert_has_calls(calls)

    def verify_fetch(self, task, target, status):
        """
        Runs the task and verifies a regular fetch.
        """
        task.write = MagicMock(side_effect=lambda story: story)

        delays = (
            SKIPPED_DELAY,
            SUCCESS_DELAY,
            SKIPPED_DELAY,
            SKIPPED_DELAY,
        )

        self.verify_run(task, delays)
        task.write.assert_called_once_with(target)
        assert status in target.flavors
        assert task.state['key'] == 4

    def verify_empty(self, task, fetcher):
        """
        Runs the task and verifies an empty fetch.
        """
        task.skip_writer.write = MagicMock()

        target = fetcher.add(key=1, date=1)
        target.meta['chapters'].clear()

        delays = (
            SKIPPED_DELAY,
            SKIPPED_DELAY,
        )

        self.verify_run(task, delays)
        task.skip_writer.write.assert_called_once_with(target)

    def verify_failure(self, task, fetcher):
        """
        Runs the task and verifies a failed fetch.
        """
        task.write = MagicMock(side_effect=lambda story: story)
        fetcher.fetch = MagicMock(side_effect=StorySourceError)

        delays = (
            FAILURE_DELAY,
            FAILURE_DELAY,
        )

        self.verify_run(task, delays)
        task.write.assert_not_called()

    def test_created_story(self, task, fimfiction):
        """
        Tests updating for a created story.
        """
        target = fimfiction.add(key=1, date=1)

        self.verify_fetch(task, target, UpdateStatus.CREATED)

    def test_revived_story(self, task, fimfarchive, fimfiction):
        """
        Tests updating for a revived story.
        """
        target = fimfarchive.add(key=1, date=1)
        other = fimfiction.add(key=1, date=1)

        target.merge = MagicMock(return_value=target)
        self.verify_fetch(task, target, UpdateStatus.REVIVED)
        target.merge.assert_called_once_with(meta=other.meta)

    def test_updated_story(self, task, fimfarchive, fimfiction):
        """
        Tests updating for an updated story.
        """
        fimfarchive.add(key=1, date=0)
        target = fimfiction.add(key=1, date=1)

        self.verify_fetch(task, target, UpdateStatus.UPDATED)

    def test_deleted_story(self, task, fimfarchive):
        """
        Test updating for a deleted story.
        """
        target = fimfarchive.add(key=1, date=1)

        self.verify_fetch(task, target, UpdateStatus.DELETED)

    def test_cleared_story(self, task, fimfarchive, fimfiction):
        """
        Tests updating for a cleared story.
        """
        target = fimfarchive.add(key=1, date=0)
        other = fimfiction.add(key=1, date=1)
        other.meta['chapters'].clear()

        self.verify_fetch(task, target, UpdateStatus.DELETED)

    def test_empty_fimfiction_story(self, task, fimfiction):
        """
        Tests updating for an empty story from fimfiction.
        """
        self.verify_empty(task, fimfiction)

    def test_empty_fimfarchive_story(self, task, fimfarchive):
        """
        Tests updating for an empty story from fimfarchive.
        """
        self.verify_empty(task, fimfarchive)

    def test_fimfarchive_failure(self, task, fimfarchive):
        """
        Tests handling of a failure in Fimfarchive.
        """
        self.verify_failure(task, fimfarchive)

    def test_fimfiction_failure(self, task, fimfiction):
        """
        Tests handling of a failure in Fimfiction.
        """
        self.verify_failure(task, fimfiction)

    def test_write_epub(self, task, story):
        """
        Tests writing of a story in EPUB format.
        """
        story = story.merge(flavors=[DataFormat.EPUB])
        task.epub_writer.write = MagicMock()

        task.write(story)
        task.epub_writer.write.assert_called_once_with(story)

    def test_write_html(self, task, story):
        """
        Tests writing of a story in HTML format.
        """
        story = story.merge(flavors=[DataFormat.HTML])
        task.html_writer.write = MagicMock()

        task.write(story)
        task.html_writer.write.assert_called_once_with(story)

    def test_write_unsupported(self, task, story):
        """
        Tests `ValueError` is raised for unknown data formats.
        """
        story = story.merge(flavors=[DataFormat.FPUB])

        with pytest.raises(ValueError):
            task.write(story)