import pytest
from chat.llm.mock import MockLLMClient
from chat.llm.client import Message


@pytest.mark.asyncio
async def test_mock_returns_canned_response():
    client = MockLLMClient(canned=["Hello, world."])
    msgs = [Message(role="user", content="hi")]
    out = await client.generate(msgs, model="any")
    assert out == "Hello, world."


@pytest.mark.asyncio
async def test_mock_streams_tokens():
    client = MockLLMClient(canned=["abcd"])
    msgs = [Message(role="user", content="hi")]
    chunks = []
    async for chunk in client.stream(msgs, model="any"):
        chunks.append(chunk)
    assert "".join(chunks) == "abcd"


@pytest.mark.asyncio
async def test_mock_llm_client_embed_pops_canned():
    """T112: MockLLMClient.embed() pops a canned vector from the front
    of ``canned_embeddings`` (mirrors the existing ``canned`` queue
    pattern for generate/stream)."""
    v1 = [0.1, 0.2, 0.3]
    v2 = [0.4, 0.5, 0.6]
    client = MockLLMClient(canned=[], canned_embeddings=[v1, v2])

    out1 = await client.embed("first", model="bge-small-en-v1.5")
    out2 = await client.embed("second", model="bge-small-en-v1.5")
    assert out1 == v1
    assert out2 == v2


@pytest.mark.asyncio
async def test_mock_llm_client_embed_empty_queue_raises():
    """When the canned_embeddings queue is empty, ``embed`` must raise
    a clear failure (IndexError) so misconfigured tests don't silently
    return None or hang."""
    client = MockLLMClient(canned=[])
    with pytest.raises(IndexError):
        await client.embed("text", model="any")