"""Unit tests for per-section embedding in stage 6.

Tests _slugify_heading, section embed text construction, delete-before-upsert
ordering, v1 page skipping, upsert payload correctness, and deterministic UUIDs.
"""

from __future__ import annotations

import uuid
from unittest.mock import MagicMock, call, patch

import pytest

# ── slugify tests ────────────────────────────────────────────────────────────

from pipeline.stages import _slugify_heading


class TestSlugifyHeading:
    """Verify _slugify_heading matches frontend TableOfContents.tsx slugify."""

    def test_simple_heading(self):
        assert _slugify_heading("Grain Position Control") == "grain-position-control"

    def test_ampersand_and_special_chars(self):
        # Consecutive non-alphanumeric chars collapse to a single hyphen
        assert _slugify_heading("LFO Routing & Modulation") == "lfo-routing-modulation"

    def test_leading_trailing_special(self):
        assert _slugify_heading("  —Hello World!  ") == "hello-world"

    def test_numbers_preserved(self):
        assert _slugify_heading("Step 1: Setup") == "step-1-setup"

    def test_empty_string(self):
        assert _slugify_heading("") == ""

    def test_only_special_chars(self):
        assert _slugify_heading("!@#$%") == ""

    def test_unicode_stripped(self):
        assert _slugify_heading("Café Sounds") == "caf-sounds"

    def test_multiple_hyphens_collapse(self):
        assert _slugify_heading("A -- B --- C") == "a-b-c"


# ── Deterministic UUID tests ─────────────────────────────────────────────────

_QDRANT_NAMESPACE = uuid.UUID("a1b2c3d4-e5f6-7890-abcd-ef1234567890")


class TestDeterministicUUIDs:
    """Verify same page+section always produces the same point ID."""

    def test_same_input_same_uuid(self):
        id1 = str(uuid.uuid5(_QDRANT_NAMESPACE, "ts:page-abc:grain-position-control"))
        id2 = str(uuid.uuid5(_QDRANT_NAMESPACE, "ts:page-abc:grain-position-control"))
        assert id1 == id2

    def test_different_section_different_uuid(self):
        id1 = str(uuid.uuid5(_QDRANT_NAMESPACE, "ts:page-abc:section-a"))
        id2 = str(uuid.uuid5(_QDRANT_NAMESPACE, "ts:page-abc:section-b"))
        assert id1 != id2


# ── QdrantManager section methods ────────────────────────────────────────────


class TestQdrantManagerSections:
    """Test upsert_technique_sections and delete_sections_by_page_id."""

    def _make_manager(self):
        """Create a QdrantManager with a mocked client."""
        with patch("pipeline.qdrant_client.QdrantClient") as MockClient:
            mock_client = MockClient.return_value
            from pipeline.qdrant_client import QdrantManager
            settings = MagicMock()
            settings.qdrant_url = "http://localhost:6333"
            settings.qdrant_collection = "test_collection"
            settings.embedding_dimensions = 768
            mgr = QdrantManager(settings)
            mgr._client = mock_client
            return mgr, mock_client

    def test_upsert_builds_correct_payloads(self):
        mgr, mock_client = self._make_manager()
        sections = [
            {
                "page_id": "p1",
                "creator_id": "c1",
                "creator_name": "Keota",
                "title": "Granular Synthesis",
                "slug": "granular-synthesis",
                "section_heading": "Grain Position Control",
                "section_anchor": "grain-position-control",
                "topic_category": "Sound Design",
                "topic_tags": ["granular", "synthesis"],
                "summary": "Control the grain position parameter.",
            },
        ]
        vectors = [[0.1] * 768]

        mgr.upsert_technique_sections(sections, vectors)

        # Verify upsert was called
        assert mock_client.upsert.called
        points = mock_client.upsert.call_args[1]["points"]
        assert len(points) == 1

        payload = points[0].payload
        assert payload["type"] == "technique_section"
        assert payload["page_id"] == "p1"
        assert payload["section_heading"] == "Grain Position Control"
        assert payload["section_anchor"] == "grain-position-control"
        assert payload["slug"] == "granular-synthesis"

        # Verify deterministic UUID
        expected_id = str(uuid.uuid5(_QDRANT_NAMESPACE, "ts:p1:grain-position-control"))
        assert points[0].id == expected_id

    def test_upsert_count_mismatch_skips(self):
        mgr, mock_client = self._make_manager()
        mgr.upsert_technique_sections([{"page_id": "p1"}], [[0.1], [0.2]])
        assert not mock_client.upsert.called

    def test_upsert_empty_list_skips(self):
        mgr, mock_client = self._make_manager()
        mgr.upsert_technique_sections([], [])
        assert not mock_client.upsert.called

    def test_summary_truncated_to_200_chars(self):
        mgr, mock_client = self._make_manager()
        long_summary = "x" * 500
        sections = [{
            "page_id": "p1", "section_heading": "H", "section_anchor": "h",
            "summary": long_summary,
        }]
        vectors = [[0.1] * 768]
        mgr.upsert_technique_sections(sections, vectors)
        payload = mock_client.upsert.call_args[1]["points"][0].payload
        assert len(payload["summary"]) == 200

    def test_delete_sections_by_page_id(self):
        mgr, mock_client = self._make_manager()
        mgr.delete_sections_by_page_id("p1")
        assert mock_client.delete.called
        filter_arg = mock_client.delete.call_args[1]["points_selector"]
        # Verify filter has both page_id and type conditions
        must_conditions = filter_arg.must
        assert len(must_conditions) == 2
        keys = {c.key for c in must_conditions}
        assert keys == {"page_id", "type"}

    def test_delete_sections_logs_on_failure(self):
        mgr, mock_client = self._make_manager()
        mock_client.delete.side_effect = Exception("connection refused")
        # Should not raise
        mgr.delete_sections_by_page_id("p1")


# ── Stage 6 section embedding logic ─────────────────────────────────────────

class TestStage6SectionEmbedding:
    """Test the section embedding block within stage6_embed_and_index.

    Uses mocked DB, embedding client, and QdrantManager to verify:
    - v2 pages produce section points
    - v1 pages are skipped
    - delete is called before upsert
    - embed text includes creator/page/section context
    - sections with empty headings are skipped
    - subsection content is included in embed text
    """

    def _make_page(self, page_id="p1", creator_id="c1", format_="v2",
                   body_sections=None, title="Granular Synthesis",
                   slug="granular-synthesis"):
        """Create a mock TechniquePage-like object."""
        page = MagicMock()
        page.id = page_id
        page.creator_id = creator_id
        page.body_sections_format = format_
        page.body_sections = body_sections
        page.title = title
        page.slug = slug
        page.topic_category = "Sound Design"
        page.topic_tags = ["granular"]
        page.summary = "Page summary"
        return page

    def test_v1_page_produces_zero_sections(self):
        """Pages with body_sections_format != 'v2' should be skipped."""
        page = self._make_page(format_="v1", body_sections=[
            {"heading": "Section A", "content": "Content A"},
        ])
        v2_pages = [p for p in [page] if getattr(p, "body_sections_format", "v1") == "v2"]
        assert len(v2_pages) == 0

    def test_v2_page_none_body_sections(self):
        """Page with body_sections=None → skipped (not a list)."""
        page = self._make_page(format_="v2", body_sections=None)
        v2_pages = [p for p in [page] if getattr(p, "body_sections_format", "v1") == "v2"]
        assert len(v2_pages) == 1
        # body_sections is None → not a list → skipped in the loop
        assert not isinstance(page.body_sections, list)

    def test_section_empty_heading_skipped(self):
        """Sections with empty heading should be skipped."""
        page = self._make_page(body_sections=[
            {"heading": "", "content": "Orphan content"},
            {"heading": "Valid", "content": "Real content"},
        ])
        sections_with_heading = [
            s for s in page.body_sections
            if isinstance(s, dict) and s.get("heading", "").strip()
        ]
        assert len(sections_with_heading) == 1
        assert sections_with_heading[0]["heading"] == "Valid"

    def test_subsection_content_included_in_embed_text(self):
        """Section with subsections should include subsection content."""
        section = {
            "heading": "Grain Position Control",
            "content": "Main content",
            "subsections": [
                {"heading": "Fine Tuning", "content": "Fine tune the position."},
                {"heading": "Automation", "content": "Automate grain pos."},
            ],
        }

        # Reproduce the embed text construction from stage 6
        creator_name = "Keota"
        page_title = "Granular Synthesis"
        heading = section["heading"]
        section_content = section.get("content", "")
        subsection_parts = []
        for sub in section.get("subsections", []):
            if isinstance(sub, dict):
                sub_heading = sub.get("heading", "")
                sub_content = sub.get("content", "")
                if sub_heading:
                    subsection_parts.append(f"{sub_heading}: {sub_content}")
                elif sub_content:
                    subsection_parts.append(sub_content)

        embed_text = (
            f"{creator_name} {page_title} — {heading}: "
            f"{section_content} {' '.join(subsection_parts)}"
        ).strip()

        assert "Fine Tuning: Fine tune the position." in embed_text
        assert "Automation: Automate grain pos." in embed_text
        assert "Keota Granular Synthesis" in embed_text

    def test_subsection_no_direct_content(self):
        """Section with subsections but no direct content still embeds subsection text."""
        section = {
            "heading": "Advanced Techniques",
            "content": "",
            "subsections": [
                {"heading": "Sub A", "content": "Content A"},
            ],
        }
        heading = section["heading"]
        section_content = section.get("content", "")
        subsection_parts = []
        for sub in section.get("subsections", []):
            if isinstance(sub, dict):
                sub_heading = sub.get("heading", "")
                sub_content = sub.get("content", "")
                if sub_heading:
                    subsection_parts.append(f"{sub_heading}: {sub_content}")
                elif sub_content:
                    subsection_parts.append(sub_content)

        embed_text = (
            f"Creator Page — {heading}: "
            f"{section_content} {' '.join(subsection_parts)}"
        ).strip()

        assert "Sub A: Content A" in embed_text

    def test_delete_called_before_upsert_ordering(self):
        """Verify delete_sections_by_page_id is called before upsert_technique_sections."""
        call_order = []
        mock_qdrant = MagicMock()
        mock_qdrant.delete_sections_by_page_id.side_effect = lambda pid: call_order.append(("delete", pid))
        mock_qdrant.upsert_technique_sections.side_effect = lambda s, v: call_order.append(("upsert", len(s)))

        mock_embed = MagicMock()
        mock_embed.embed.return_value = [[0.1] * 768]  # One vector

        page = self._make_page(body_sections=[
            {"heading": "Section A", "content": "Content A"},
        ])

        creator_map = {str(page.creator_id): "TestCreator"}
        v2_pages = [page]
        page_id_str = str(page.id)

        # Simulate the section embedding block
        for p in v2_pages:
            body_sections = p.body_sections
            if not isinstance(body_sections, list):
                continue
            creator_name = creator_map.get(str(p.creator_id), "")
            mock_qdrant.delete_sections_by_page_id(str(p.id))

            section_texts = []
            section_dicts = []
            for section in body_sections:
                if not isinstance(section, dict):
                    continue
                heading = section.get("heading", "")
                if not heading or not heading.strip():
                    continue
                section_anchor = _slugify_heading(heading)
                section_texts.append(f"{creator_name} {p.title} — {heading}")
                section_dicts.append({"page_id": str(p.id), "section_anchor": section_anchor})

            if section_texts:
                vectors = mock_embed.embed(section_texts)
                if vectors:
                    mock_qdrant.upsert_technique_sections(section_dicts, vectors)

        assert call_order[0][0] == "delete"
        assert call_order[1][0] == "upsert"