"""Phase 4 TDD: Mist JSON API router explicit registration in main.py.

Tests are written RED first.  Run before touching main.py and
musehub/api/routes/musehub/__init__.py to confirm failure, then implement.

The mists router must be:
  1. Listed in _DIRECT_REGISTERED in __init__.py (excluded from auto-discovery).
  2. Explicitly imported and included in main.py alongside api_identities_router,
     api_orgs_router, etc.
  3. Reachable via the OpenAPI schema at /api/mists paths.

These tests do not require DB state — they operate against the live app
instance and its route table.
"""
from __future__ import annotations

import pytest
from httpx import AsyncClient


class TestMistsRouterDirectRegistration:
    def test_mists_excluded_from_auto_discovery(self) -> None:
        """'mists' must appear in _DIRECT_REGISTERED so the package __init__
        does not auto-include it."""
        from musehub.api.routes.musehub import _DIRECT_REGISTERED
        assert "mists" in _DIRECT_REGISTERED, (
            "'mists' must be in _DIRECT_REGISTERED to prevent double-registration"
        )

    def test_mists_router_imported_in_main(self) -> None:
        """main.py must import the mists router explicitly."""
        import musehub.main as _main
        src = open(_main.__file__).read()
        assert "mists" in src, (
            "main.py must explicitly import or reference the mists router"
        )

    def test_mists_router_registered_via_include_router(self) -> None:
        """main.py must call app.include_router with the mists router."""
        import musehub.main as _main
        src = open(_main.__file__).read()
        # The module import line + the include_router call must both be present.
        assert "api_mists_router" in src or "mists_router" in src or (
            "from musehub.api.routes.musehub.mists import router" in src
        ), "main.py must explicitly include the mists router by name"


class TestMistsRouterOpenAPI:
    @pytest.mark.asyncio
    async def test_mists_paths_in_openapi_schema(self, client: AsyncClient) -> None:
        """GET /api/openapi.json must list /api/mists paths."""
        r = await client.get("/api/openapi.json")
        assert r.status_code == 200
        schema = r.json()
        paths = schema.get("paths", {})
        mist_paths = [p for p in paths if "/mists" in p]
        assert len(mist_paths) > 0, (
            f"No /mists paths found in OpenAPI schema. "
            f"Registered paths sample: {list(paths.keys())[:20]}"
        )

    @pytest.mark.asyncio
    async def test_create_mist_operation_in_schema(self, client: AsyncClient) -> None:
        r = await client.get("/api/openapi.json")
        schema = r.json()
        paths = schema.get("paths", {})
        assert "/api/mists" in paths or any(
            p.endswith("/mists") for p in paths
        ), f"POST /api/mists not found in schema paths: {[p for p in paths if 'mist' in p]}"

    @pytest.mark.asyncio
    async def test_explore_mists_operation_in_schema(self, client: AsyncClient) -> None:
        r = await client.get("/api/openapi.json")
        schema = r.json()
        paths = schema.get("paths", {})
        assert any("mists/explore" in p for p in paths), (
            f"GET /api/mists/explore not found in schema"
        )


class TestMistsRouterEndpoints:
    @pytest.mark.asyncio
    async def test_explore_endpoint_returns_200(self, client: AsyncClient) -> None:
        """GET /api/mists/explore must return 200, not 404."""
        r = await client.get("/api/mists/explore")
        assert r.status_code == 200, (
            f"Expected 200 from /api/mists/explore; got {r.status_code} — "
            "router may not be registered"
        )

    @pytest.mark.asyncio
    async def test_explore_response_is_valid_json(self, client: AsyncClient) -> None:
        r = await client.get("/api/mists/explore")
        assert r.status_code == 200
        body = r.json()
        assert "mists" in body

    @pytest.mark.asyncio
    async def test_get_nonexistent_mist_returns_404_not_422(
        self, client: AsyncClient
    ) -> None:
        """A valid mist_id that doesn't exist should return 404, not 422 (unprocessable
        entity from FastAPI if the route is missing or double-registered)."""
        r = await client.get("/api/mists/Abc123Xyz789")
        assert r.status_code in (404, 200), (
            f"Expected 404 for unknown mist, got {r.status_code} — "
            "422 indicates a routing problem (possibly double-registration)"
        )

    @pytest.mark.asyncio
    async def test_no_duplicate_operation_ids(self, client: AsyncClient) -> None:
        """Double-registration causes duplicate operationIds — FastAPI raises on startup."""
        r = await client.get("/api/openapi.json")
        assert r.status_code == 200, (
            "OpenAPI schema returned non-200 — likely duplicate operationId "
            "from double-registering the mists router"
        )
        schema = r.json()
        # Collect all operationIds from mist-related paths.
        op_ids: list[str] = []
        for path, methods in schema.get("paths", {}).items():
            if "mist" not in path:
                continue
            for method_data in methods.values():
                if isinstance(method_data, dict) and "operationId" in method_data:
                    op_ids.append(method_data["operationId"])
        assert len(op_ids) == len(set(op_ids)), (
            f"Duplicate operationIds detected — router registered twice: "
            f"{[x for x in op_ids if op_ids.count(x) > 1]}"
        )