import re
import unittest

import pytest

from scrapy.http import HtmlResponse, XmlResponse
from scrapy.link import Link
from scrapy.linkextractors.lxmlhtml import LxmlLinkExtractor
from tests import get_testdata


# a hack to skip base class tests in pytest
class Base:
    class LinkExtractorTestCase(unittest.TestCase):
        extractor_cls = None

        def setUp(self):
            body = get_testdata('link_extractor', 'sgml_linkextractor.html')
            self.response = HtmlResponse(url='http://example.com/index', body=body)

        def test_urls_type(self):
            ''' Test that the resulting urls are str objects '''
            lx = self.extractor_cls()
            self.assertTrue(all(isinstance(link.url, str)
                                for link in lx.extract_links(self.response)))

        def test_extract_all_links(self):
            lx = self.extractor_cls()
            self.assertEqual([link for link in lx.extract_links(self.response)], [
                Link(url='http://example.com/sample1.html', text=u''),
                Link(url='http://example.com/sample2.html', text=u'sample 2'),
                Link(url='http://example.com/sample3.html', text=u'sample 3 text'),
                Link(url='http://www.google.com/something', text=u''),
                Link(url='http://example.com/innertag.html', text=u'inner tag'),
            ])

        def test_extract_filter_allow(self):
            lx = self.extractor_cls(allow=('sample', ))
            self.assertEqual([link for link in lx.extract_links(self.response)], [
                Link(url='http://example.com/sample1.html', text=u''),
                Link(url='http://example.com/sample2.html', text=u'sample 2'),
                Link(url='http://example.com/sample3.html', text=u'sample 3 text'),
            ])

        def test_extract_filter_allow_with_duplicates(self):
            lx = self.extractor_cls(allow=('sample', ), unique=False)
            self.assertEqual([link for link in lx.extract_links(self.response)], [
                Link(url='http://example.com/sample1.html', text=u''),
                Link(url='http://example.com/sample2.html', text=u'sample 2'),
                Link(url='http://example.com/sample3.html', text=u'sample 3 text'),
                Link(url='http://example.com/sample3.html', text=u'sample 3 repetition'),
            ])

        def test_extract_filter_allow_and_deny(self):
            lx = self.extractor_cls(allow=('sample', ), deny=('3', ))
            self.assertEqual([link for link in lx.extract_links(self.response)], [
                Link(url='http://example.com/sample1.html', text=u''),
                Link(url='http://example.com/sample2.html', text=u'sample 2'),
            ])

        def test_extract_filter_allowed_domains(self):
            lx = self.extractor_cls(allow_domains=('google.com', ))
            self.assertEqual([link for link in lx.extract_links(self.response)], [
                Link(url='http://www.google.com/something', text=u''),
            ])

        def test_extraction_using_single_values(self):
            '''Test the extractor's behaviour among different situations'''

            lx = self.extractor_cls(allow='sample')
            self.assertEqual([link for link in lx.extract_links(self.response)], [
                Link(url='http://example.com/sample1.html', text=u''),
                Link(url='http://example.com/sample2.html', text=u'sample 2'),
                Link(url='http://example.com/sample3.html', text=u'sample 3 text'),
            ])

            lx = self.extractor_cls(allow='sample', deny='3')
            self.assertEqual([link for link in lx.extract_links(self.response)], [
                Link(url='http://example.com/sample1.html', text=u''),
                Link(url='http://example.com/sample2.html', text=u'sample 2'),
            ])

            lx = self.extractor_cls(allow_domains='google.com')
            self.assertEqual([link for link in lx.extract_links(self.response)], [
                Link(url='http://www.google.com/something', text=u''),
            ])

            lx = self.extractor_cls(deny_domains='example.com')
            self.assertEqual([link for link in lx.extract_links(self.response)], [
                Link(url='http://www.google.com/something', text=u''),
            ])

        def test_nofollow(self):
            '''Test the extractor's behaviour for links with rel="nofollow"'''

            html = b"""<html><head><title>Page title<title>
            <body>
            <div class='links'>
            <p><a href="/about.html">About us</a></p>
            </div>
            <div>
            <p><a href="/follow.html">Follow this link</a></p>
            </div>
            <div>
            <p><a href="/nofollow.html" rel="nofollow">Dont follow this one</a></p>
            </div>
            <div>
            <p><a href="/nofollow2.html" rel="blah">Choose to follow or not</a></p>
            </div>
            <div>
            <p><a href="http://google.com/something" rel="external nofollow">External link not to follow</a></p>
            </div>
            </body></html>"""
            response = HtmlResponse("http://example.org/somepage/index.html", body=html)

            lx = self.extractor_cls()
            self.assertEqual(lx.extract_links(response), [
                Link(url='http://example.org/about.html', text=u'About us'),
                Link(url='http://example.org/follow.html', text=u'Follow this link'),
                Link(url='http://example.org/nofollow.html', text=u'Dont follow this one', nofollow=True),
                Link(url='http://example.org/nofollow2.html', text=u'Choose to follow or not'),
                Link(url='http://google.com/something', text=u'External link not to follow', nofollow=True),
            ])

        def test_matches(self):
            url1 = 'http://lotsofstuff.com/stuff1/index'
            url2 = 'http://evenmorestuff.com/uglystuff/index'

            lx = self.extractor_cls(allow=(r'stuff1', ))
            self.assertEqual(lx.matches(url1), True)
            self.assertEqual(lx.matches(url2), False)

            lx = self.extractor_cls(deny=(r'uglystuff', ))
            self.assertEqual(lx.matches(url1), True)
            self.assertEqual(lx.matches(url2), False)

            lx = self.extractor_cls(allow_domains=('evenmorestuff.com', ))
            self.assertEqual(lx.matches(url1), False)
            self.assertEqual(lx.matches(url2), True)

            lx = self.extractor_cls(deny_domains=('lotsofstuff.com', ))
            self.assertEqual(lx.matches(url1), False)
            self.assertEqual(lx.matches(url2), True)

            lx = self.extractor_cls(allow=('blah1',), deny=('blah2',),
                                   allow_domains=('blah1.com',),
                                   deny_domains=('blah2.com',))
            self.assertEqual(lx.matches('http://blah1.com/blah1'), True)
            self.assertEqual(lx.matches('http://blah1.com/blah2'), False)
            self.assertEqual(lx.matches('http://blah2.com/blah1'), False)
            self.assertEqual(lx.matches('http://blah2.com/blah2'), False)

        def test_restrict_xpaths(self):
            lx = self.extractor_cls(restrict_xpaths=('//div[@id="subwrapper"]', ))
            self.assertEqual([link for link in lx.extract_links(self.response)], [
                Link(url='http://example.com/sample1.html', text=u''),
                Link(url='http://example.com/sample2.html', text=u'sample 2'),
            ])

        def test_restrict_xpaths_encoding(self):
            """Test restrict_xpaths with encodings"""
            html = b"""<html><head><title>Page title<title>
            <body><p><a href="item/12.html">Item 12</a></p>
            <div class='links'>
            <p><a href="/about.html">About us\xa3</a></p>
            </div>
            <div>
            <p><a href="/nofollow.html">This shouldn't be followed</a></p>
            </div>
            </body></html>"""
            response = HtmlResponse("http://example.org/somepage/index.html", body=html, encoding='windows-1252')

            lx = self.extractor_cls(restrict_xpaths="//div[@class='links']")
            self.assertEqual(lx.extract_links(response),
                             [Link(url='http://example.org/about.html', text=u'About us\xa3')])

        def test_restrict_xpaths_with_html_entities(self):
            html = b'<html><body><p><a href="/&hearts;/you?c=&euro;">text</a></p></body></html>'
            response = HtmlResponse("http://example.org/somepage/index.html", body=html, encoding='iso8859-15')
            links = self.extractor_cls(restrict_xpaths='//p').extract_links(response)
            self.assertEqual(links,
                             [Link(url='http://example.org/%E2%99%A5/you?c=%E2%82%AC', text=u'text')])

        def test_restrict_xpaths_concat_in_handle_data(self):
            """html entities cause SGMLParser to call handle_data hook twice"""
            body = b"""<html><body><div><a href="/foo">&gt;\xbe\xa9&lt;\xb6\xab</a></body></html>"""
            response = HtmlResponse("http://example.org", body=body, encoding='gb18030')
            lx = self.extractor_cls(restrict_xpaths="//div")
            self.assertEqual(lx.extract_links(response),
                             [Link(url='http://example.org/foo', text=u'>\u4eac<\u4e1c',
                                   fragment='', nofollow=False)])

        def test_restrict_css(self):
            lx = self.extractor_cls(restrict_css=('#subwrapper a',))
            self.assertEqual(lx.extract_links(self.response), [
                Link(url='http://example.com/sample2.html', text=u'sample 2')
            ])

        def test_restrict_css_and_restrict_xpaths_together(self):
            lx = self.extractor_cls(restrict_xpaths=('//div[@id="subwrapper"]', ),
                                    restrict_css=('#subwrapper + a', ))
            self.assertEqual([link for link in lx.extract_links(self.response)], [
                Link(url='http://example.com/sample1.html', text=u''),
                Link(url='http://example.com/sample2.html', text=u'sample 2'),
                Link(url='http://example.com/sample3.html', text=u'sample 3 text'),
            ])

        def test_area_tag_with_unicode_present(self):
            body = b"""<html><body>\xbe\xa9<map><area href="http://example.org/foo" /></map></body></html>"""
            response = HtmlResponse("http://example.org", body=body, encoding='utf-8')
            lx = self.extractor_cls()
            lx.extract_links(response)
            lx.extract_links(response)
            lx.extract_links(response)
            self.assertEqual(lx.extract_links(response),
                             [Link(url='http://example.org/foo', text=u'',
                                   fragment='', nofollow=False)])

        def test_encoded_url(self):
            body = b"""<html><body><div><a href="?page=2">BinB</a></body></html>"""
            response = HtmlResponse("http://known.fm/AC%2FDC/", body=body, encoding='utf8')
            lx = self.extractor_cls()
            self.assertEqual(lx.extract_links(response), [
                Link(url='http://known.fm/AC%2FDC/?page=2', text=u'BinB', fragment='', nofollow=False),
            ])

        def test_encoded_url_in_restricted_xpath(self):
            body = b"""<html><body><div><a href="?page=2">BinB</a></body></html>"""
            response = HtmlResponse("http://known.fm/AC%2FDC/", body=body, encoding='utf8')
            lx = self.extractor_cls(restrict_xpaths="//div")
            self.assertEqual(lx.extract_links(response), [
                Link(url='http://known.fm/AC%2FDC/?page=2', text=u'BinB', fragment='', nofollow=False),
            ])

        def test_ignored_extensions(self):
            # jpg is ignored by default
            html = b"""<a href="page.html">asd</a> and <a href="photo.jpg">"""
            response = HtmlResponse("http://example.org/", body=html)
            lx = self.extractor_cls()
            self.assertEqual(lx.extract_links(response), [
                Link(url='http://example.org/page.html', text=u'asd'),
            ])

            # override denied extensions
            lx = self.extractor_cls(deny_extensions=['html'])
            self.assertEqual(lx.extract_links(response), [
                Link(url='http://example.org/photo.jpg'),
            ])

        def test_process_value(self):
            """Test restrict_xpaths with encodings"""
            html = b"""
            <a href="javascript:goToPage('../other/page.html','photo','width=600,height=540,scrollbars'); return false">Link text</a>
            <a href="/about.html">About us</a>
            """
            response = HtmlResponse("http://example.org/somepage/index.html", body=html, encoding='windows-1252')

            def process_value(value):
                m = re.search("javascript:goToPage\('(.*?)'", value)
                if m:
                    return m.group(1)

            lx = self.extractor_cls(process_value=process_value)
            self.assertEqual(lx.extract_links(response),
                             [Link(url='http://example.org/other/page.html', text='Link text')])

        def test_base_url_with_restrict_xpaths(self):
            html = b"""<html><head><title>Page title<title><base href="http://otherdomain.com/base/" />
            <body><p><a href="item/12.html">Item 12</a></p>
            </body></html>"""
            response = HtmlResponse("http://example.org/somepage/index.html", body=html)
            lx = self.extractor_cls(restrict_xpaths="//p")
            self.assertEqual(lx.extract_links(response),
                             [Link(url='http://otherdomain.com/base/item/12.html', text='Item 12')])

        def test_attrs(self):
            lx = self.extractor_cls(attrs="href")
            self.assertEqual(lx.extract_links(self.response), [
                Link(url='http://example.com/sample1.html', text=u''),
                Link(url='http://example.com/sample2.html', text=u'sample 2'),
                Link(url='http://example.com/sample3.html', text=u'sample 3 text'),
                Link(url='http://www.google.com/something', text=u''),
                Link(url='http://example.com/innertag.html', text=u'inner tag'),
            ])

            lx = self.extractor_cls(attrs=("href","src"), tags=("a","area","img"), deny_extensions=())
            self.assertEqual(lx.extract_links(self.response), [
                Link(url='http://example.com/sample1.html', text=u''),
                Link(url='http://example.com/sample2.html', text=u'sample 2'),
                Link(url='http://example.com/sample2.jpg', text=u''),
                Link(url='http://example.com/sample3.html', text=u'sample 3 text'),
                Link(url='http://www.google.com/something', text=u''),
                Link(url='http://example.com/innertag.html', text=u'inner tag'),
            ])

            lx = self.extractor_cls(attrs=None)
            self.assertEqual(lx.extract_links(self.response), [])

        def test_tags(self):
            html = b"""<html><area href="sample1.html"></area><a href="sample2.html">sample 2</a><img src="sample2.jpg"/></html>"""
            response = HtmlResponse("http://example.com/index.html", body=html)

            lx = self.extractor_cls(tags=None)
            self.assertEqual(lx.extract_links(response), [])

            lx = self.extractor_cls()
            self.assertEqual(lx.extract_links(response), [
                Link(url='http://example.com/sample1.html', text=u''),
                Link(url='http://example.com/sample2.html', text=u'sample 2'),
            ])

            lx = self.extractor_cls(tags="area")
            self.assertEqual(lx.extract_links(response), [
                Link(url='http://example.com/sample1.html', text=u''),
            ])

            lx = self.extractor_cls(tags="a")
            self.assertEqual(lx.extract_links(response), [
                Link(url='http://example.com/sample2.html', text=u'sample 2'),
            ])

            lx = self.extractor_cls(tags=("a","img"), attrs=("href", "src"), deny_extensions=())
            self.assertEqual(lx.extract_links(response), [
                Link(url='http://example.com/sample2.html', text=u'sample 2'),
                Link(url='http://example.com/sample2.jpg', text=u''),
            ])

        def test_tags_attrs(self):
            html = b"""
            <html><body>
            <div id="item1" data-url="get?id=1"><a href="#">Item 1</a></div>
            <div id="item2" data-url="get?id=2"><a href="#">Item 2</a></div>
            </body></html>
            """
            response = HtmlResponse("http://example.com/index.html", body=html)

            lx = self.extractor_cls(tags='div', attrs='data-url')
            self.assertEqual(lx.extract_links(response), [
                Link(url='http://example.com/get?id=1', text=u'Item 1', fragment='', nofollow=False),
                Link(url='http://example.com/get?id=2', text=u'Item 2', fragment='', nofollow=False)
            ])

            lx = self.extractor_cls(tags=('div',), attrs=('data-url',))
            self.assertEqual(lx.extract_links(response), [
                Link(url='http://example.com/get?id=1', text=u'Item 1', fragment='', nofollow=False),
                Link(url='http://example.com/get?id=2', text=u'Item 2', fragment='', nofollow=False)
            ])

        def test_xhtml(self):
            xhtml = b"""
    <?xml version="1.0"?>
    <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
        "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
    <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
    <head>
        <title>XHTML document title</title>
    </head>
    <body>
        <div class='links'>
        <p><a href="/about.html">About us</a></p>
        </div>
        <div>
        <p><a href="/follow.html">Follow this link</a></p>
        </div>
        <div>
        <p><a href="/nofollow.html" rel="nofollow">Dont follow this one</a></p>
        </div>
        <div>
        <p><a href="/nofollow2.html" rel="blah">Choose to follow or not</a></p>
        </div>
        <div>
        <p><a href="http://google.com/something" rel="external nofollow">External link not to follow</a></p>
        </div>
    </body>
    </html>
            """

            response = HtmlResponse("http://example.com/index.xhtml", body=xhtml)

            lx = self.extractor_cls()
            self.assertEqual(lx.extract_links(response),
                             [Link(url='http://example.com/about.html', text=u'About us', fragment='', nofollow=False),
                              Link(url='http://example.com/follow.html', text=u'Follow this link', fragment='', nofollow=False),
                              Link(url='http://example.com/nofollow.html', text=u'Dont follow this one', fragment='', nofollow=True),
                              Link(url='http://example.com/nofollow2.html', text=u'Choose to follow or not', fragment='', nofollow=False),
                              Link(url='http://google.com/something', text=u'External link not to follow', nofollow=True)]
                            )

            response = XmlResponse("http://example.com/index.xhtml", body=xhtml)

            lx = self.extractor_cls()
            self.assertEqual(lx.extract_links(response),
                             [Link(url='http://example.com/about.html', text=u'About us', fragment='', nofollow=False),
                              Link(url='http://example.com/follow.html', text=u'Follow this link', fragment='', nofollow=False),
                              Link(url='http://example.com/nofollow.html', text=u'Dont follow this one', fragment='', nofollow=True),
                              Link(url='http://example.com/nofollow2.html', text=u'Choose to follow or not', fragment='', nofollow=False),
                              Link(url='http://google.com/something', text=u'External link not to follow', nofollow=True)]
                            )

        def test_link_wrong_href(self):
            html = b"""
            <a href="http://example.org/item1.html">Item 1</a>
            <a href="http://[example.org/item2.html">Item 2</a>
            <a href="http://example.org/item3.html">Item 3</a>
            """
            response = HtmlResponse("http://example.org/index.html", body=html)
            lx = self.extractor_cls()
            self.assertEqual([link for link in lx.extract_links(response)], [
                Link(url='http://example.org/item1.html', text=u'Item 1', nofollow=False),
                Link(url='http://example.org/item3.html', text=u'Item 3', nofollow=False),
            ])


class LxmlLinkExtractorTestCase(Base.LinkExtractorTestCase):
    extractor_cls = LxmlLinkExtractor

    def test_link_wrong_href(self):
        html = b"""
        <a href="http://example.org/item1.html">Item 1</a>
        <a href="http://[example.org/item2.html">Item 2</a>
        <a href="http://example.org/item3.html">Item 3</a>
        """
        response = HtmlResponse("http://example.org/index.html", body=html)
        lx = self.extractor_cls()
        self.assertEqual([link for link in lx.extract_links(response)], [
            Link(url='http://example.org/item1.html', text=u'Item 1', nofollow=False),
            Link(url='http://example.org/item3.html', text=u'Item 3', nofollow=False),
        ])

    @pytest.mark.xfail
    def test_restrict_xpaths_with_html_entities(self):
        super(LxmlLinkExtractorTestCase, self).test_restrict_xpaths_with_html_entities()

