"""Tests for LinkParser module

Tests URL parsing for various platforms:
- Bilibili video URLs
- Bilibili article URLs
- Zhihu answer URLs
- Zhihu zhuanlan URLs
- Short link resolution (b23.tv)
- Unknown URL handling
"""

import pytest
from unittest.mock import patch, MagicMock


class TestLinkParserBilibiliVideo:
    """Tests for Bilibili video URL parsing"""

    def test_parse_bilibili_video_url_returns_correct_parsed_link(self):
        """Test 1: 解析B站视频URL返回正确的 ParsedLink (platform=bilibili, type=video, id=BVxxx)"""
        from kb_workflow.pipeline.link_parser import LinkParser, ParsedLink

        parser = LinkParser()
        result = parser.parse("https://www.bilibili.com/video/BV1GJ411x7Qw")

        assert result is not None
        assert result.platform == "bilibili"
        assert result.content_type == "video"
        assert result.content_id == "BV1GJ411x7Qw"
        assert result.original_url == "https://www.bilibili.com/video/BV1GJ411x7Qw"

    def test_parse_bilibili_video_url_without_www(self):
        """B站视频URL不带www也能正确解析"""
        from kb_workflow.pipeline.link_parser import LinkParser

        parser = LinkParser()
        result = parser.parse("https://bilibili.com/video/BV1GJ411x7Qw")

        assert result is not None
        assert result.platform == "bilibili"
        assert result.content_type == "video"
        assert result.content_id == "BV1GJ411x7Qw"

    def test_parse_bilibili_video_url_with_http(self):
        """B站视频URL使用http也能正确解析"""
        from kb_workflow.pipeline.link_parser import LinkParser

        parser = LinkParser()
        result = parser.parse("http://www.bilibili.com/video/BV1GJ411x7Qw")

        assert result is not None
        assert result.platform == "bilibili"
        assert result.content_type == "video"


class TestLinkParserBilibiliArticle:
    """Tests for Bilibili article URL parsing"""

    def test_parse_bilibili_article_url_returns_correct_parsed_link(self):
        """Test 2: 解析B站专栏URL返回正确的 ParsedLink (platform=bilibili, type=article, id=cvxxx)"""
        from kb_workflow.pipeline.link_parser import LinkParser

        parser = LinkParser()
        result = parser.parse("https://www.bilibili.com/read/cv12345678")

        assert result is not None
        assert result.platform == "bilibili"
        assert result.content_type == "article"
        assert result.content_id == "cv12345678"

    def test_parse_bilibili_article_url_with_article_prefix(self):
        """B站专栏URL使用article前缀也能正确解析"""
        from kb_workflow.pipeline.link_parser import LinkParser

        parser = LinkParser()
        result = parser.parse("https://www.bilibili.com/article/cv12345678")

        assert result is not None
        assert result.platform == "bilibili"
        assert result.content_type == "article"
        assert result.content_id == "cv12345678"


class TestLinkParserZhihuAnswer:
    """Tests for Zhihu answer URL parsing"""

    def test_parse_zhihu_answer_url_returns_correct_parsed_link(self):
        """Test 3: 解析知乎问答URL返回正确的 ParsedLink (platform=zhihu, type=answer, id=xxx)"""
        from kb_workflow.pipeline.link_parser import LinkParser

        parser = LinkParser()
        result = parser.parse("https://www.zhihu.com/question/12345678/answer/87654321")

        assert result is not None
        assert result.platform == "zhihu"
        assert result.content_type == "answer"
        assert result.content_id == "87654321"

    def test_parse_zhihu_answer_url_without_www(self):
        """知乎问答URL不带www也能正确解析"""
        from kb_workflow.pipeline.link_parser import LinkParser

        parser = LinkParser()
        result = parser.parse("https://zhihu.com/question/12345678/answer/87654321")

        assert result is not None
        assert result.platform == "zhihu"
        assert result.content_type == "answer"


class TestLinkParserZhihuZhuanlan:
    """Tests for Zhihu zhuanlan URL parsing"""

    def test_parse_zhihu_zhuanlan_url_returns_correct_parsed_link(self):
        """Test 4: 解析知乎专栏URL返回正确的 ParsedLink (platform=zhihu, type=zhuanlan, id=xxx)"""
        from kb_workflow.pipeline.link_parser import LinkParser

        parser = LinkParser()
        result = parser.parse("https://zhuanlan.zhihu.com/p/12345678")

        assert result is not None
        assert result.platform == "zhihu"
        assert result.content_type == "zhuanlan"
        assert result.content_id == "12345678"


class TestLinkParserShortLink:
    """Tests for short link resolution"""

    @patch("kb_workflow.pipeline.link_parser.requests.head")
    def test_parse_b23tv_shortlink_resolves_to_real_url(self, mock_head):
        """Test 5: 解析b23.tv短链返回解析后的真实URL"""
        from kb_workflow.pipeline.link_parser import LinkParser

        # Mock the redirect response
        mock_response = MagicMock()
        mock_response.status_code = 200
        mock_response.url = "https://www.bilibili.com/video/BV1GJ411x7Qw"
        mock_head.return_value = mock_response

        parser = LinkParser()
        result = parser.parse("https://b23.tv/abc123")

        assert result is not None
        assert result.platform == "bilibili"
        assert result.content_type == "video"
        assert result.content_id == "BV1GJ411x7Qw"
        assert result.resolved_url == "https://www.bilibili.com/video/BV1GJ411x7Qw"

    @patch("kb_workflow.pipeline.link_parser.requests.head")
    def test_shortlink_resolution_uses_allow_redirects(self, mock_head):
        """短链解析应该使用 allow_redirects=True"""
        from kb_workflow.pipeline.link_parser import LinkParser

        mock_response = MagicMock()
        mock_response.status_code = 200
        mock_response.url = "https://www.bilibili.com/video/BV1GJ411x7Qw"
        mock_head.return_value = mock_response

        parser = LinkParser()
        parser.parse("https://b23.tv/abc123")

        mock_head.assert_called_once()
        call_kwargs = mock_head.call_args[1]
        assert call_kwargs.get("allow_redirects") is True


class TestLinkParserUnknownURL:
    """Tests for unknown URL handling"""

    def test_parse_unknown_url_returns_none(self):
        """Test 6: 无法识别的URL返回None（不抛异常）"""
        from kb_workflow.pipeline.link_parser import LinkParser

        parser = LinkParser()
        result = parser.parse("https://www.youtube.com/watch?v=dQw4w9WgXcQ")

        assert result is None

    def test_parse_invalid_url_returns_none(self):
        """无效URL返回None"""
        from kb_workflow.pipeline.link_parser import LinkParser

        parser = LinkParser()
        result = parser.parse("not a valid url")

        assert result is None

    def test_parse_empty_string_returns_none(self):
        """空字符串返回None"""
        from kb_workflow.pipeline.link_parser import LinkParser

        parser = LinkParser()
        result = parser.parse("")

        assert result is None


class TestParsedLink:
    """Tests for ParsedLink dataclass"""

    def test_parsed_link_has_all_required_fields(self):
        """ParsedLink 应包含所有必需字段"""
        from kb_workflow.pipeline.link_parser import ParsedLink

        link = ParsedLink(
            platform="bilibili",
            content_type="video",
            content_id="BV1GJ411x7Qw",
            original_url="https://www.bilibili.com/video/BV1GJ411x7Qw",
            resolved_url="https://www.bilibili.com/video/BV1GJ411x7Qw"
        )

        assert link.platform == "bilibili"
        assert link.content_type == "video"
        assert link.content_id == "BV1GJ411x7Qw"
        assert link.original_url == "https://www.bilibili.com/video/BV1GJ411x7Qw"
        assert link.resolved_url == "https://www.bilibili.com/video/BV1GJ411x7Qw"

    def test_parsed_link_resolved_url_defaults_to_original(self):
        """ParsedLink 的 resolved_url 默认等于 original_url"""
        from kb_workflow.pipeline.link_parser import ParsedLink

        link = ParsedLink(
            platform="bilibili",
            content_type="video",
            content_id="BV1GJ411x7Qw",
            original_url="https://www.bilibili.com/video/BV1GJ411x7Qw"
        )

        assert link.resolved_url == link.original_url