"""Tests for ratatoskr.sessions per docs/contracts/issues/2.contract.md."""

import httpx
import pytest
import respx

from ratatoskr.sessions import (
    AgentNotFound,
    InvalidCursor,
    SessionApiFailed,
    SessionPage,
    create_session,
    list_sessions,
)


class TestCreateSession:
    @respx.mock
    async def test_happy_create(self) -> None:
        """happy_create [happy,tracer]: full 201 body -> SessionInfo with create-origin defaults."""
        respx.post("https://w.example/sessions").mock(
            return_value=httpx.Response(
                201,
                json={
                    "session_id": "550e8400-e29b-41d4-a716-446655440000",
                    "agent_id": "mimir",
                    "message_count": 0,
                    "created_at": "2026-04-15T12:00:00+00:00",
                    "last_active": "2026-04-15T12:00:00+00:00",
                    "metadata": {},
                },
            )
        )
        async with httpx.AsyncClient(base_url="https://w.example") as client:
            info = await create_session(client, "mimir")
        assert info.session_id == "550e8400-e29b-41d4-a716-446655440000"
        assert info.agent_id == "mimir"
        assert info.created_at == "2026-04-15T12:00:00+00:00"
        assert info.last_active == "2026-04-15T12:00:00+00:00"
        assert info.metadata == {}
        assert info.message_count == 0
        # INV-001 create-origin fixed defaults
        assert info.name is None
        assert info.archived is False
        assert info.tags == []

    @respx.mock
    async def test_happy_create_with_metadata(self) -> None:
        """happy_create_with_metadata: response carries metadata -> SessionInfo.metadata matches."""
        respx.post("https://w.example/sessions").mock(
            return_value=httpx.Response(
                201,
                json={
                    "session_id": "s1",
                    "agent_id": "mimir",
                    "message_count": 0,
                    "created_at": "2026-04-15T12:00:00+00:00",
                    "last_active": "2026-04-15T12:00:00+00:00",
                    "metadata": {"model": "glm5-turbo"},
                },
            )
        )
        async with httpx.AsyncClient(base_url="https://w.example") as client:
            info = await create_session(client, "mimir")
        assert info.metadata == {"model": "glm5-turbo"}

    @respx.mock
    async def test_request_body_shape(self) -> None:
        """request_body_shape [trace]: outbound JSON is exactly {"agent_id": <arg>}."""
        import json as _json

        route = respx.post("https://w.example/sessions").mock(
            return_value=httpx.Response(
                201,
                json={
                    "session_id": "s1",
                    "agent_id": "mimir",
                    "message_count": 0,
                    "created_at": "2026-04-15T12:00:00+00:00",
                    "last_active": "2026-04-15T12:00:00+00:00",
                    "metadata": {},
                },
            )
        )
        async with httpx.AsyncClient(base_url="https://w.example") as client:
            await create_session(client, "mimir")
        body = _json.loads(route.calls[0].request.content)
        assert body == {"agent_id": "mimir"}

    @respx.mock
    async def test_unknown_agent_id(self) -> None:
        """unknown_agent_id: 404 -> AgentNotFound(agent_id=<arg>)."""
        respx.post("https://w.example/sessions").mock(
            return_value=httpx.Response(404, json={"error": "unknown_agent_id"})
        )
        async with httpx.AsyncClient(base_url="https://w.example") as client:
            with pytest.raises(AgentNotFound) as exc_info:
                await create_session(client, "mimir")
        assert exc_info.value.agent_id == "mimir"

    @respx.mock
    async def test_validation_failed(self) -> None:
        """validation_failed: 422 -> SessionApiFailed(status=422); body truncated."""
        respx.post("https://w.example/sessions").mock(
            return_value=httpx.Response(
                422,
                json={"error_code": "validation_failed", "message": "missing agent_id"},
            )
        )
        async with httpx.AsyncClient(base_url="https://w.example") as client:
            with pytest.raises(SessionApiFailed) as exc_info:
                await create_session(client, "mimir")
        assert exc_info.value.status == 422
        assert len(exc_info.value.body) <= 1024

    @respx.mock
    async def test_unexpected_status_truncates(self) -> None:
        """unexpected_status_truncates: 500 + 5000-byte body -> SessionApiFailed; body == 1024."""
        big = b"x" * 5000
        respx.post("https://w.example/sessions").mock(
            return_value=httpx.Response(500, content=big)
        )
        async with httpx.AsyncClient(base_url="https://w.example") as client:
            with pytest.raises(SessionApiFailed) as exc_info:
                await create_session(client, "mimir")
        assert exc_info.value.status == 500
        assert exc_info.value.body == big[:1024]

    @respx.mock
    async def test_empty_agent_id(self) -> None:
        """empty_agent_id [adversarial]: '' -> AssertionError; no HTTP issued."""
        route = respx.post("https://w.example/sessions").mock(
            return_value=httpx.Response(201, content=b"{}")
        )
        async with httpx.AsyncClient(base_url="https://w.example") as client:
            with pytest.raises(AssertionError):
                await create_session(client, "")
        assert route.call_count == 0


def _list_item(
    *,
    session_id: str = "s1",
    agent_id: str = "mimir",
    created_at: str = "2026-04-15T12:00:00+00:00",
    last_active: str = "2026-04-15T12:05:00+00:00",
    metadata: dict[str, object] | None = None,
    name: str | None = "Research session",
    archived: bool = False,
    tags: list[str] | None = None,
) -> dict[str, object]:
    """Build a GET /sessions list-item body for tests."""
    item: dict[str, object] = {
        "session_id": session_id,
        "agent_id": agent_id,
        "created_at": created_at,
        "last_active": last_active,
        "metadata": metadata if metadata is not None else {},
        "name": name,
        "archived": archived,
        "tags": tags if tags is not None else ["work"],
    }
    return item


class TestListSessions:
    @respx.mock
    async def test_explicit_null_list_defaults(self) -> None:
        """INV-002: explicit-null archived -> False; explicit-null tags -> []."""
        raw_item = {
            "session_id": "s1",
            "agent_id": "mimir",
            "created_at": "2026-04-15T12:00:00+00:00",
            "last_active": "2026-04-15T12:05:00+00:00",
            "metadata": {},
            "name": None,
            "archived": None,
            "tags": None,
        }
        respx.get("https://w.example/sessions").mock(
            return_value=httpx.Response(
                200, json={"items": [raw_item], "next_cursor": None}
            )
        )
        async with httpx.AsyncClient(base_url="https://w.example") as client:
            page = await list_sessions(client)
        info = page.items[0]
        assert info.archived is False, "explicit-null archived must default to False"
        assert info.tags == [], "explicit-null tags must default to []"
        assert info.name is None

    @respx.mock
    async def test_happy_first_page(self) -> None:
        """happy_first_page [happy,tracer]: one item + next_cursor -> SessionPage shape."""
        respx.get("https://w.example/sessions").mock(
            return_value=httpx.Response(
                200,
                json={
                    "items": [_list_item()],
                    "next_cursor": "v1.eyJhYmMifQ",
                },
            )
        )
        async with httpx.AsyncClient(base_url="https://w.example") as client:
            page = await list_sessions(client)
        assert isinstance(page, SessionPage)
        assert len(page.items) == 1
        assert page.next_cursor == "v1.eyJhYmMifQ"
        info = page.items[0]
        assert info.session_id == "s1"
        assert info.message_count is None  # INV-002: not in list response
        assert info.name == "Research session"
        assert info.archived is False
        assert info.tags == ["work"]

    @respx.mock
    async def test_happy_last_page(self) -> None:
        """happy_last_page: next_cursor=null -> SessionPage(next_cursor=None)."""
        respx.get("https://w.example/sessions").mock(
            return_value=httpx.Response(
                200,
                json={"items": [_list_item()], "next_cursor": None},
            )
        )
        async with httpx.AsyncClient(base_url="https://w.example") as client:
            page = await list_sessions(client)
        assert page.next_cursor is None

    @respx.mock
    async def test_empty_results(self) -> None:
        """empty_results: {items: [], next_cursor: null} -> SessionPage([], None)."""
        respx.get("https://w.example/sessions").mock(
            return_value=httpx.Response(200, json={"items": [], "next_cursor": None})
        )
        async with httpx.AsyncClient(base_url="https://w.example") as client:
            page = await list_sessions(client)
        assert page == SessionPage(items=[], next_cursor=None)

    @respx.mock
    async def test_include_archived_query(self) -> None:
        """include_archived_query: True -> has param; default -> NO param at all."""
        route = respx.get("https://w.example/sessions").mock(
            return_value=httpx.Response(
                200, json={"items": [], "next_cursor": None}
            )
        )
        async with httpx.AsyncClient(base_url="https://w.example") as client:
            await list_sessions(client, include_archived=True)
            await list_sessions(client)  # default
        url_with = str(route.calls[0].request.url)
        url_default = str(route.calls[1].request.url)
        assert "include_archived=true" in url_with
        assert "include_archived" not in url_default

    @respx.mock
    async def test_cursor_threaded(self) -> None:
        """cursor_threaded: cursor=opaque -> URL has cursor=opaque."""
        route = respx.get("https://w.example/sessions").mock(
            return_value=httpx.Response(
                200, json={"items": [], "next_cursor": None}
            )
        )
        async with httpx.AsyncClient(base_url="https://w.example") as client:
            await list_sessions(client, cursor="opaque-from-prev-page")
        assert "cursor=opaque-from-prev-page" in str(route.calls[0].request.url)

    @respx.mock
    async def test_limit_query(self) -> None:
        """limit_query: limit=10 -> URL has limit=10."""
        route = respx.get("https://w.example/sessions").mock(
            return_value=httpx.Response(
                200, json={"items": [], "next_cursor": None}
            )
        )
        async with httpx.AsyncClient(base_url="https://w.example") as client:
            await list_sessions(client, limit=10)
        assert "limit=10" in str(route.calls[0].request.url)

    @respx.mock
    async def test_invalid_cursor_server(self) -> None:
        """invalid_cursor_server: 422 cursor_invalid -> InvalidCursor(raw=<passed cursor>)."""
        respx.get("https://w.example/sessions").mock(
            return_value=httpx.Response(
                422,
                json={"error_code": "cursor_invalid", "message": "bad cursor"},
            )
        )
        async with httpx.AsyncClient(base_url="https://w.example") as client:
            with pytest.raises(InvalidCursor) as exc_info:
                await list_sessions(client, cursor="bogus")
        assert exc_info.value.raw == "bogus"

    @respx.mock
    async def test_other_validation_failed(self) -> None:
        """other_validation_failed: 422 other error_code -> SessionApiFailed(422); truncated."""
        respx.get("https://w.example/sessions").mock(
            return_value=httpx.Response(
                422,
                json={"error_code": "validation_failed", "message": "limit out of range"},
            )
        )
        async with httpx.AsyncClient(base_url="https://w.example") as client:
            with pytest.raises(SessionApiFailed) as exc_info:
                await list_sessions(client)
        assert exc_info.value.status == 422
        assert len(exc_info.value.body) <= 1024

    @respx.mock
    async def test_unexpected_status_truncates(self) -> None:
        """unexpected_status_truncates: 500 + 5000-byte body -> SessionApiFailed; body == 1024."""
        big = b"x" * 5000
        respx.get("https://w.example/sessions").mock(
            return_value=httpx.Response(500, content=big)
        )
        async with httpx.AsyncClient(base_url="https://w.example") as client:
            with pytest.raises(SessionApiFailed) as exc_info:
                await list_sessions(client)
        assert exc_info.value.status == 500
        assert exc_info.value.body == big[:1024]

    @respx.mock
    async def test_limit_below_one(self) -> None:
        """limit_below_one [adversarial]: limit=0 -> AssertionError; no HTTP."""
        route = respx.get("https://w.example/sessions").mock(
            return_value=httpx.Response(200, json={"items": [], "next_cursor": None})
        )
        async with httpx.AsyncClient(base_url="https://w.example") as client:
            with pytest.raises(AssertionError):
                await list_sessions(client, limit=0)
        assert route.call_count == 0

    @respx.mock
    async def test_limit_above_max(self) -> None:
        """limit_above_max [adversarial]: limit=300 -> AssertionError; no HTTP."""
        route = respx.get("https://w.example/sessions").mock(
            return_value=httpx.Response(200, json={"items": [], "next_cursor": None})
        )
        async with httpx.AsyncClient(base_url="https://w.example") as client:
            with pytest.raises(AssertionError):
                await list_sessions(client, limit=300)
        assert route.call_count == 0

    @respx.mock
    async def test_empty_cursor(self) -> None:
        """empty_cursor [adversarial]: cursor='' -> AssertionError; no HTTP."""
        route = respx.get("https://w.example/sessions").mock(
            return_value=httpx.Response(200, json={"items": [], "next_cursor": None})
        )
        async with httpx.AsyncClient(base_url="https://w.example") as client:
            with pytest.raises(AssertionError):
                await list_sessions(client, cursor="")
        assert route.call_count == 0