import io
import zipfile

import pytest

from app.services.dmarc_parser import DMARCParser
from app.tests.test_data import SAMPLE_XML, SAMPLE_XML_WITH_NAMESPACE


class TestDMARCParser:
    """Tests for the DMARC XML parser."""

    def test_parse_xml_report(self):
        """Test parsing a plain XML DMARC report."""
        xml_bytes = SAMPLE_XML.encode("utf-8")
        result = DMARCParser.parse_file(xml_bytes, "report.xml")

        # Report metadata (flat keys from _parse_xml)
        assert result["report_id"] == "123456789"
        assert result["org_name"] == "google.com"
        assert result["email"] == "noreply-dmarc-support@google.com"
        assert result["begin_timestamp"] == 1597449600
        assert result["end_timestamp"] == 1597535999

        # Policy published
        assert result["domain"] == "example.com"
        assert result["policy"]["p"] == "none"

        # Records
        assert len(result["records"]) == 1
        record = result["records"][0]
        assert record["source_ip"] == "203.0.113.1"
        assert record["count"] == 2
        assert record["disposition"] == "none"
        assert record["dkim_result"] == "pass"
        assert record["spf_result"] == "fail"
        assert record["header_from"] == "example.com"

        # Summary
        assert result["summary"]["total_count"] == 2
        assert result["summary"]["passed_count"] == 2  # dkim passed
        assert result["summary"]["failed_count"] == 0

    def test_parse_zip_report(self):
        """Test parsing a DMARC report inside a ZIP archive."""
        xml_bytes = SAMPLE_XML.encode("utf-8")

        zip_buffer = io.BytesIO()
        with zipfile.ZipFile(zip_buffer, "w") as zf:
            zf.writestr("report.xml", xml_bytes)
        zip_content = zip_buffer.getvalue()

        result = DMARCParser.parse_file(zip_content, "report.zip")

        assert result["report_id"] == "123456789"
        assert result["domain"] == "example.com"
        assert len(result["records"]) == 1

    def test_file_too_large(self):
        """Test that files exceeding the size limit are rejected."""
        large_content = b"x" * (11 * 1024 * 1024)  # 11 MB
        with pytest.raises(ValueError, match="too large"):
            DMARCParser.parse_file(large_content, "report.xml")

    def test_invalid_xml(self):
        """Test that invalid XML raises a ValueError."""
        with pytest.raises(ValueError, match="Error parsing DMARC XML"):
            DMARCParser.parse_file(b"not xml at all", "report.xml")

    def test_parse_xml_report_with_namespace(self):
        """Test parsing a DMARC XML report that uses an XML namespace (e.g. web.de/gmx.net)."""
        xml_bytes = SAMPLE_XML_WITH_NAMESPACE.encode("utf-8")
        result = DMARCParser.parse_file(xml_bytes, "report.xml")

        # Metadata
        assert result["report_id"] == "987654321"
        assert result["org_name"] == "web.de"
        assert result["email"] == "dmarc@web.de"
        assert result["begin_timestamp"] == 1597449600
        assert result["end_timestamp"] == 1597535999

        # Policy published
        assert result["domain"] == "example.com"
        assert result["policy"]["p"] == "reject"

        # Records
        assert len(result["records"]) == 1
        record = result["records"][0]
        assert record["source_ip"] == "198.51.100.5"
        assert record["count"] == 3
        assert record["disposition"] == "reject"
        assert record["dkim_result"] == "pass"
        assert record["spf_result"] == "pass"
        assert record["header_from"] == "example.com"

        # Summary
        assert result["summary"]["total_count"] == 3
        assert result["summary"]["passed_count"] == 3
        assert result["summary"]["failed_count"] == 0

    def test_unsupported_extension_returns_none(self):
        """Test that an unsupported file extension raises ValueError."""
        with pytest.raises(ValueError, match="Could not extract XML"):
            DMARCParser.parse_file(b"some content", "report.pdf")

    def test_bad_zip_file_returns_no_xml_content(self):
        """A corrupt ZIP should be handled as no extractable XML content."""
        with pytest.raises(ValueError, match="Could not extract XML"):
            DMARCParser.parse_file(b"not a zip file", "report.zip")

    def test_bad_gzip_file_returns_no_xml_content(self):
        """A corrupt GZIP should be handled as no extractable XML content."""
        with pytest.raises(ValueError, match="Could not extract XML"):
            DMARCParser.parse_file(b"not a gzip file", "report.gz")

    def test_parse_xml_without_report_metadata(self):
        """Missing report_metadata should not crash parsing otherwise valid XML."""
        xml = b"""
        <feedback>
            <policy_published>
                <domain>example.com</domain>
                <p>none</p>
            </policy_published>
        </feedback>
        """

        result = DMARCParser.parse_file(xml, "report.xml")

        assert result["domain"] == "example.com"
        assert result["records"] == []
        assert result["summary"]["total_count"] == 0
