"""
Offline unit tests for the nightly integrity-check endpoint (Phase C item 2).

All external clients are mocked - no shared services are contacted.
The endpoint must be strictly read-only: these tests assert that no
delete/purge/update methods are ever invoked.
"""

import pytest
from unittest.mock import AsyncMock

from src.routers.maintenance import (
    IntegrityCheckRequest,
    classify_collection,
    integrity_check,
    run_integrity_check,
)

TEST_USER = "llm_tester"
TENANT_PREFIX = f"users/{TEST_USER}"


def _mock_clients(
    wiki_pages,
    chunk_refs,
    graph_docs,
    collections,
):
    wiki_client = AsyncMock()
    wiki_client.list_all_pages = AsyncMock(return_value=wiki_pages)

    vector_service = AsyncMock()
    vector_service.get_all_chunk_references = AsyncMock(return_value=chunk_refs)

    graph_service = AsyncMock()
    graph_service.get_all_document_references = AsyncMock(return_value=graph_docs)

    qdrant = AsyncMock()
    qdrant.list_collections = AsyncMock(return_value=collections)

    return wiki_client, vector_service, graph_service, qdrant


class TestRunIntegrityCheck:
    @pytest.mark.asyncio
    async def test_full_report(self):
        wiki_pages = [
            # tenant pages
            {"id": 1, "path": f"{TENANT_PREFIX}/a", "title": "A"},
            {"id": 2, "path": f"{TENANT_PREFIX}/b", "title": "B"},
            # another tenant's page (defines a known tenant, out of scope here)
            {"id": 50, "path": "users/jpmschweitzer/x", "title": "X"},
        ]
        chunk_refs = [
            # page 1 has vectors; page 2 has none (silent-skip victim)
            {"chunk_id": "c1", "page_id": 1, "doc_type": "wiki"},
            # orphan: page 99 no longer exists in the wiki
            {"chunk_id": "c9", "page_id": 99, "doc_type": "wiki"},
            # non-wiki chunk is ignored by the wiki-side checks
            {"chunk_id": "cd", "document_id": "d1", "doc_type": "document"},
        ]
        graph_docs = [
            {"page_id": 1, "path": f"{TENANT_PREFIX}/a", "title": "A", "doc_type": "wiki"},
            # stale Document node: wiki page 77 is gone
            {"page_id": 77, "path": f"{TENANT_PREFIX}/old", "title": "Old", "doc_type": "wiki"},
        ]
        collections = [
            {"name": "library_desk_jpmschweitzer", "vectors_count": 10},
            {"name": "library_desk_llm_tester", "vectors_count": 2},
            {"name": "library_desk_ghost_tenant", "vectors_count": 1},
            {"name": "open-webui_files", "vectors_count": 5},
        ]

        wiki_client, vector_service, graph_service, qdrant = _mock_clients(
            wiki_pages, chunk_refs, graph_docs, collections
        )

        report = await run_integrity_check(
            TEST_USER, vector_service, graph_service, wiki_client, qdrant
        )

        assert report.success is True
        assert report.user == TEST_USER

        # Pages without vectors: page 2 only (page 1 has c1)
        assert [p["page_id"] for p in report.pages_without_vectors] == [2]

        # Orphaned vectors: c9 -> page 99
        assert report.orphaned_vector_chunks == 1
        assert report.orphaned_vector_page_ids == [99]

        # Collections: llm_tester is test residue, ghost_tenant unknown,
        # jpmschweitzer expected, open-webui foreign
        flagged = {c["name"]: c["category"] for c in report.unexpected_collections}
        assert flagged == {
            "library_desk_llm_tester": "test_residue",
            "library_desk_ghost_tenant": "unknown_tenant",
        }
        assert report.foreign_collections == 1

        # Graph documents without wiki counterparts: page 77
        assert [d["page_id"] for d in report.documents_without_wiki] == [77]

        assert report.counts["tenant_wiki_pages"] == 2
        assert report.counts["pages_without_vectors"] == 1
        assert report.counts["documents_without_wiki"] == 1
        assert report.duration_ms >= 0

    @pytest.mark.asyncio
    async def test_read_only_no_mutations(self):
        """The integrity check must never call any destructive method."""
        wiki_client, vector_service, graph_service, qdrant = _mock_clients(
            [], [], [], []
        )

        await run_integrity_check(
            TEST_USER, vector_service, graph_service, wiki_client, qdrant
        )

        for mock, destructive in (
            (vector_service, ("purge_chunks_by_ids", "delete_page_chunks")),
            (graph_service, ("purge_orphan_entities", "purge_stale_documents_by_ids",
                             "delete_page", "cleanup_broken_relationships")),
            (qdrant, ("delete_collection", "delete_by_ids", "delete_by_filter")),
            (wiki_client, ("delete_page", "update_page", "create_page")),
        ):
            for name in destructive:
                assert not getattr(mock, name).await_count, (
                    f"integrity check must be read-only but called {name}"
                )


class TestIntegrityEndpoint:
    @pytest.mark.asyncio
    async def test_caches_latest_report_in_redis(self):
        wiki_client, vector_service, graph_service, qdrant = _mock_clients(
            [{"id": 1, "path": f"{TENANT_PREFIX}/a", "title": "A"}],
            [{"chunk_id": "c1", "page_id": 1, "doc_type": "wiki"}],
            [],
            [],
        )
        redis = AsyncMock()

        report = await integrity_check(
            request=IntegrityCheckRequest(user=TEST_USER),
            vector_service=vector_service,
            graph_service=graph_service,
            wiki_client=wiki_client,
            qdrant=qdrant,
            redis=redis,
            api_key="",
        )

        assert report.success is True
        redis.setex.assert_awaited_once()
        key = redis.setex.await_args.args[0]
        assert key == f"library:integrity:latest:{TEST_USER}"

    def test_requires_user(self):
        with pytest.raises(Exception):
            IntegrityCheckRequest(user=" ")


class TestClassifyCollection:
    def test_expected_tenant(self):
        assert classify_collection(
            "library_desk_jpmschweitzer", {"jpmschweitzer"}
        ) == "expected"

    def test_test_residue_beats_known_tenant(self):
        # Even if the test tenant has wiki pages during a run, its
        # collections are still flagged as residue.
        assert classify_collection(
            "library_desk_llm_tester", {"llm_tester"}
        ) == "test_residue"

    def test_unknown_tenant(self):
        assert classify_collection(
            "volatile_mystery", {"jpmschweitzer"}
        ) == "unknown_tenant"

    def test_foreign_and_foreign_residue(self):
        assert classify_collection("open-webui_files", set()) == "foreign"
        assert classify_collection("core_ai_user_test_at_example_com", set()) == \
            "foreign_test_residue"
        assert classify_collection("test_user", set()) == "foreign_test_residue"