import logging
import tempfile
import warnings

from twisted.internet import defer
from twisted.trial import unittest
from pytest import raises

import scrapy
from scrapy.crawler import Crawler, CrawlerRunner, CrawlerProcess
from scrapy.settings import Settings, default_settings
from scrapy.spiderloader import SpiderLoader
from scrapy.utils.log import configure_logging, get_scrapy_root_handler
from scrapy.utils.spider import DefaultSpider
from scrapy.utils.misc import load_object
from scrapy.extensions.throttle import AutoThrottle
from scrapy.extensions import telnet


class BaseCrawlerTest(unittest.TestCase):

    def assertOptionIsDefault(self, settings, key):
        self.assertIsInstance(settings, Settings)
        self.assertEqual(settings[key], getattr(default_settings, key))


class CrawlerTestCase(BaseCrawlerTest):

    def setUp(self):
        self.crawler = Crawler(DefaultSpider, Settings())

    def test_deprecated_attribute_spiders(self):
        with warnings.catch_warnings(record=True) as w:
            spiders = self.crawler.spiders
            self.assertEqual(len(w), 1)
            self.assertIn("Crawler.spiders", str(w[0].message))
            sl_cls = load_object(self.crawler.settings['SPIDER_LOADER_CLASS'])
            self.assertIsInstance(spiders, sl_cls)

            self.crawler.spiders
            self.assertEqual(len(w), 1, "Warn deprecated access only once")

    def test_populate_spidercls_settings(self):
        spider_settings = {'TEST1': 'spider', 'TEST2': 'spider'}
        project_settings = {'TEST1': 'project', 'TEST3': 'project'}

        class CustomSettingsSpider(DefaultSpider):
            custom_settings = spider_settings

        settings = Settings()
        settings.setdict(project_settings, priority='project')
        crawler = Crawler(CustomSettingsSpider, settings)

        self.assertEqual(crawler.settings.get('TEST1'), 'spider')
        self.assertEqual(crawler.settings.get('TEST2'), 'spider')
        self.assertEqual(crawler.settings.get('TEST3'), 'project')

        self.assertFalse(settings.frozen)
        self.assertTrue(crawler.settings.frozen)

    def test_crawler_accepts_dict(self):
        crawler = Crawler(DefaultSpider, {'foo': 'bar'})
        self.assertEqual(crawler.settings['foo'], 'bar')
        self.assertOptionIsDefault(crawler.settings, 'RETRY_ENABLED')

    def test_crawler_accepts_None(self):
        crawler = Crawler(DefaultSpider)
        self.assertOptionIsDefault(crawler.settings, 'RETRY_ENABLED')

    def test_crawler_rejects_spider_objects(self):
        with raises(ValueError):
            Crawler(DefaultSpider())


class SpiderSettingsTestCase(unittest.TestCase):
    def test_spider_custom_settings(self):
        class MySpider(scrapy.Spider):
            name = 'spider'
            custom_settings = {
                'AUTOTHROTTLE_ENABLED': True
            }

        crawler = Crawler(MySpider, {})
        enabled_exts = [e.__class__ for e in crawler.extensions.middlewares]
        self.assertIn(AutoThrottle, enabled_exts)


class CrawlerLoggingTestCase(unittest.TestCase):
    def test_no_root_handler_installed(self):
        handler = get_scrapy_root_handler()
        if handler is not None:
            logging.root.removeHandler(handler)

        class MySpider(scrapy.Spider):
            name = 'spider'

        crawler = Crawler(MySpider, {})
        assert get_scrapy_root_handler() is None

    def test_spider_custom_settings_log_level(self):
        log_file = self.mktemp()
        class MySpider(scrapy.Spider):
            name = 'spider'
            custom_settings = {
                'LOG_LEVEL': 'INFO',
                'LOG_FILE': log_file,
                # disable telnet if not available to avoid an extra warning
                'TELNETCONSOLE_ENABLED': telnet.TWISTED_CONCH_AVAILABLE,
            }

        configure_logging()
        self.assertEqual(get_scrapy_root_handler().level, logging.DEBUG)
        crawler = Crawler(MySpider, {})
        self.assertEqual(get_scrapy_root_handler().level, logging.INFO)
        info_count = crawler.stats.get_value('log_count/INFO')
        logging.debug('debug message')
        logging.info('info message')
        logging.warning('warning message')
        logging.error('error message')

        with open(log_file, 'rb') as fo:
            logged = fo.read().decode('utf8')

        self.assertNotIn('debug message', logged)
        self.assertIn('info message', logged)
        self.assertIn('warning message', logged)
        self.assertIn('error message', logged)
        self.assertEqual(crawler.stats.get_value('log_count/ERROR'), 1)
        self.assertEqual(crawler.stats.get_value('log_count/WARNING'), 1)
        self.assertEqual(
            crawler.stats.get_value('log_count/INFO') - info_count, 1)
        self.assertEqual(crawler.stats.get_value('log_count/DEBUG', 0), 0)


class SpiderLoaderWithWrongInterface(object):

    def unneeded_method(self):
        pass


class CustomSpiderLoader(SpiderLoader):
    pass


class CrawlerRunnerTestCase(BaseCrawlerTest):

    def test_spider_manager_verify_interface(self):
        settings = Settings({
            'SPIDER_LOADER_CLASS': 'tests.test_crawler.SpiderLoaderWithWrongInterface'
        })
        with warnings.catch_warnings(record=True) as w:
            self.assertRaises(AttributeError, CrawlerRunner, settings)
            self.assertEqual(len(w), 1)
            self.assertIn("SPIDER_LOADER_CLASS", str(w[0].message))
            self.assertIn("scrapy.interfaces.ISpiderLoader", str(w[0].message))

    def test_crawler_runner_accepts_dict(self):
        runner = CrawlerRunner({'foo': 'bar'})
        self.assertEqual(runner.settings['foo'], 'bar')
        self.assertOptionIsDefault(runner.settings, 'RETRY_ENABLED')

    def test_crawler_runner_accepts_None(self):
        runner = CrawlerRunner()
        self.assertOptionIsDefault(runner.settings, 'RETRY_ENABLED')

    def test_deprecated_attribute_spiders(self):
        with warnings.catch_warnings(record=True) as w:
            runner = CrawlerRunner(Settings())
            spiders = runner.spiders
            self.assertEqual(len(w), 1)
            self.assertIn("CrawlerRunner.spiders", str(w[0].message))
            self.assertIn("CrawlerRunner.spider_loader", str(w[0].message))
            sl_cls = load_object(runner.settings['SPIDER_LOADER_CLASS'])
            self.assertIsInstance(spiders, sl_cls)

    def test_spidermanager_deprecation(self):
        with warnings.catch_warnings(record=True) as w:
            runner = CrawlerRunner({
                'SPIDER_MANAGER_CLASS': 'tests.test_crawler.CustomSpiderLoader'
            })
            self.assertIsInstance(runner.spider_loader, CustomSpiderLoader)
            self.assertEqual(len(w), 1)
            self.assertIn('Please use SPIDER_LOADER_CLASS', str(w[0].message))

    def test_crawl_rejects_spider_objects(self):
        with raises(ValueError):
            CrawlerRunner().crawl(DefaultSpider())

    def test_create_crawler_rejects_spider_objects(self):
        with raises(ValueError):
            CrawlerRunner().create_crawler(DefaultSpider())


class CrawlerProcessTest(BaseCrawlerTest):
    def test_crawler_process_accepts_dict(self):
        runner = CrawlerProcess({'foo': 'bar'})
        self.assertEqual(runner.settings['foo'], 'bar')
        self.assertOptionIsDefault(runner.settings, 'RETRY_ENABLED')

    def test_crawler_process_accepts_None(self):
        runner = CrawlerProcess()
        self.assertOptionIsDefault(runner.settings, 'RETRY_ENABLED')


class ExceptionSpider(scrapy.Spider):
    name = 'exception'

    @classmethod
    def from_crawler(cls, crawler, *args, **kwargs):
        raise ValueError('Exception in from_crawler method')


class NoRequestsSpider(scrapy.Spider):
    name = 'no_request'

    def start_requests(self):
        return []


class CrawlerRunnerHasSpider(unittest.TestCase):

    @defer.inlineCallbacks
    def test_crawler_runner_bootstrap_successful(self):
        runner = CrawlerRunner()
        yield runner.crawl(NoRequestsSpider)
        self.assertEqual(runner.bootstrap_failed, False)

    @defer.inlineCallbacks
    def test_crawler_runner_bootstrap_successful_for_several(self):
        runner = CrawlerRunner()
        yield runner.crawl(NoRequestsSpider)
        yield runner.crawl(NoRequestsSpider)
        self.assertEqual(runner.bootstrap_failed, False)

    @defer.inlineCallbacks
    def test_crawler_runner_bootstrap_failed(self):
        runner = CrawlerRunner()

        try:
            yield runner.crawl(ExceptionSpider)
        except ValueError:
            pass
        else:
            self.fail('Exception should be raised from spider')

        self.assertEqual(runner.bootstrap_failed, True)

    @defer.inlineCallbacks
    def test_crawler_runner_bootstrap_failed_for_several(self):
        runner = CrawlerRunner()

        try:
            yield runner.crawl(ExceptionSpider)
        except ValueError:
            pass
        else:
            self.fail('Exception should be raised from spider')

        yield runner.crawl(NoRequestsSpider)

        self.assertEqual(runner.bootstrap_failed, True)