"""
Tests for POST /chat — persona routing, session handling, LLM mocking.
"""
import json
import pytest


def _parse_sse(text: str) -> list[dict]:
    """Extract JSON payloads from an SSE response body."""
    events = []
    for line in text.splitlines():
        if line.startswith("data: "):
            try:
                events.append(json.loads(line[6:]))
            except json.JSONDecodeError:
                pass
    return events


@pytest.mark.anyio
async def test_chat_basic(client, mock_llm):
    r = await client.post("/chat", json={"message": "Hello", "persona": "inara"})
    assert r.status_code == 200
    events = _parse_sse(r.text)
    responses = [e for e in events if e.get("type") == "response"]
    assert len(responses) == 1
    assert responses[0]["response"] == "Hello, I am a test response."
    assert responses[0]["backend"] == "claude"
    assert "session_id" in responses[0]


@pytest.mark.anyio
async def test_chat_default_persona(client, mock_llm):
    """persona defaults to 'inara' when not specified."""
    r = await client.post("/chat", json={"message": "Hi"})
    assert r.status_code == 200
    events = _parse_sse(r.text)
    assert any(e.get("type") == "response" for e in events)


@pytest.mark.anyio
async def test_chat_unknown_persona(client, mock_llm):
    r = await client.post("/chat", json={"message": "Hi", "persona": "nobody"})
    assert r.status_code == 200
    events = _parse_sse(r.text)
    errors = [e for e in events if e.get("type") == "error"]
    assert len(errors) == 1
    assert "nobody" in errors[0]["message"]


@pytest.mark.anyio
async def test_chat_path_traversal_persona(client, mock_llm):
    r = await client.post("/chat", json={"message": "Hi", "persona": "../../etc"})
    assert r.status_code == 200
    events = _parse_sse(r.text)
    errors = [e for e in events if e.get("type") == "error"]
    assert len(errors) == 1


@pytest.mark.anyio
async def test_chat_session_persists(client, mock_llm):
    """Same session_id reuses history."""
    r1 = await client.post("/chat", json={"message": "First message", "session_id": "test-sess-1"})
    r2 = await client.post("/chat", json={"message": "Second message", "session_id": "test-sess-1"})
    assert r1.status_code == 200
    assert r2.status_code == 200


@pytest.mark.anyio
async def test_sessions_list(client, mock_llm):
    """After a chat, the session appears in /sessions."""
    await client.post("/chat", json={"message": "Hello", "session_id": "test-list-sess"})
    r = await client.get("/sessions")
    assert r.status_code == 200
    sessions = r.json()["sessions"]
    ids = [s["session_id"] for s in sessions]
    assert "test-list-sess" in ids


@pytest.mark.anyio
async def test_session_history(client, mock_llm):
    await client.post("/chat", json={"message": "Hello", "session_id": "test-hist-sess"})
    r = await client.get("/history/test-hist-sess")
    assert r.status_code == 200
    msgs = r.json()["messages"]
    assert any(m["role"] == "user" and "Hello" in m["content"] for m in msgs)


@pytest.mark.anyio
async def test_session_delete(client, mock_llm):
    await client.post("/chat", json={"message": "Hello", "session_id": "test-del-sess"})
    r = await client.delete("/sessions/test-del-sess")
    assert r.status_code == 200
    assert r.json()["ok"] is True


@pytest.mark.anyio
async def test_session_delete_unknown(client):
    r = await client.delete("/sessions/does-not-exist")
    assert r.status_code == 404


@pytest.mark.anyio
async def test_backend_get(client):
    r = await client.get("/backend")
    assert r.status_code == 200
    assert r.json()["primary"] in ("claude", "gemini")


@pytest.mark.anyio
async def test_backend_set(client):
    r = await client.post("/backend", json={"primary": "gemini"})
    assert r.status_code == 200
    assert r.json()["primary"] == "gemini"
    # Reset
    await client.post("/backend", json={"primary": "claude"})


@pytest.mark.anyio
async def test_backend_set_invalid(client):
    r = await client.post("/backend", json={"primary": "gpt-4"})
    assert r.status_code == 400