import logging
import tempfile
import warnings
import unittest

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

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')


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):
        with tempfile.NamedTemporaryFile() as log_file:
            class MySpider(scrapy.Spider):
                name = 'spider'
                custom_settings = {
                    'LOG_LEVEL': 'INFO',
                    'LOG_FILE': log_file.name,
                    # 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')
            logged = log_file.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))


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(twisted.trial.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)