"""Unit tests for PubMed tool."""

from unittest.mock import AsyncMock, MagicMock

import pytest

from src.tools.pubmed import PubMedTool

# Sample PubMed XML response for mocking
SAMPLE_PUBMED_XML = """<?xml version="1.0" ?>
<PubmedArticleSet>
    <PubmedArticle>
        <MedlineCitation>
            <PMID>12345678</PMID>
            <Article>
                <ArticleTitle>Metformin in Alzheimer's Disease: A Systematic Review</ArticleTitle>
                <Abstract>
                    <AbstractText>Metformin shows neuroprotective properties...</AbstractText>
                </Abstract>
                <AuthorList>
                    <Author>
                        <LastName>Smith</LastName>
                        <ForeName>John</ForeName>
                    </Author>
                </AuthorList>
                <Journal>
                    <JournalIssue>
                        <PubDate>
                            <Year>2024</Year>
                            <Month>01</Month>
                        </PubDate>
                    </JournalIssue>
                </Journal>
            </Article>
        </MedlineCitation>
    </PubmedArticle>
</PubmedArticleSet>
"""


class TestPubMedTool:
    """Tests for PubMedTool."""

    @pytest.mark.asyncio
    async def test_search_returns_evidence(self, mocker):
        """PubMedTool should return Evidence objects from search."""
        # Mock the HTTP responses
        mock_search_response = MagicMock()
        mock_search_response.json.return_value = {"esearchresult": {"idlist": ["12345678"]}}
        mock_search_response.raise_for_status = MagicMock()

        mock_fetch_response = MagicMock()
        mock_fetch_response.text = SAMPLE_PUBMED_XML
        mock_fetch_response.raise_for_status = MagicMock()

        mock_client = AsyncMock()
        mock_client.get = AsyncMock(side_effect=[mock_search_response, mock_fetch_response])
        mock_client.__aenter__ = AsyncMock(return_value=mock_client)
        mock_client.__aexit__ = AsyncMock(return_value=None)

        mocker.patch("httpx.AsyncClient", return_value=mock_client)

        # Act
        tool = PubMedTool()
        results = await tool.search("metformin alzheimer")

        # Assert
        assert len(results) == 1
        assert results[0].citation.source == "pubmed"
        assert "Metformin" in results[0].citation.title
        assert "12345678" in results[0].citation.url

    @pytest.mark.asyncio
    async def test_search_empty_results(self, mocker):
        """PubMedTool should return empty list when no results."""
        mock_response = MagicMock()
        mock_response.json.return_value = {"esearchresult": {"idlist": []}}
        mock_response.raise_for_status = MagicMock()

        mock_client = AsyncMock()
        mock_client.get = AsyncMock(return_value=mock_response)
        mock_client.__aenter__ = AsyncMock(return_value=mock_client)
        mock_client.__aexit__ = AsyncMock(return_value=None)

        mocker.patch("httpx.AsyncClient", return_value=mock_client)

        tool = PubMedTool()
        results = await tool.search("xyznonexistentquery123")

        assert results == []

    def test_parse_pubmed_xml(self):
        """PubMedTool should correctly parse XML."""
        tool = PubMedTool()
        results = tool._parse_pubmed_xml(SAMPLE_PUBMED_XML)

        assert len(results) == 1
        assert results[0].citation.source == "pubmed"
        assert "Smith John" in results[0].citation.authors

    @pytest.mark.asyncio
    async def test_search_preprocesses_query(self, mocker):
        """Test that queries are preprocessed before search."""
        mock_search_response = MagicMock()
        mock_search_response.json.return_value = {"esearchresult": {"idlist": []}}
        mock_search_response.raise_for_status = MagicMock()

        mock_client = AsyncMock()
        mock_client.get = AsyncMock(return_value=mock_search_response)
        mock_client.__aenter__ = AsyncMock(return_value=mock_client)
        mock_client.__aexit__ = AsyncMock(return_value=None)

        mocker.patch("httpx.AsyncClient", return_value=mock_client)

        tool = PubMedTool()
        await tool.search("What drugs help with Long COVID?")

        # Verify call args
        call_args = mock_client.get.call_args
        params = call_args[1]["params"]
        term = params["term"]

        # "what" and "help" should be stripped
        assert "what" not in term.lower()
        assert "help" not in term.lower()
        # "long covid" should be expanded
        assert "PASC" in term or "post-COVID" in term