"""Tests for AI endpoints — OpenRouter HTTP calls are fully mocked."""
import os
import pytest
import pytest_asyncio
from unittest.mock import AsyncMock, patch
from httpx import AsyncClient, ASGITransport

from app.main import app
from app import db as db_module

os.environ.setdefault("JWT_SECRET", "test-secret-key-for-testing-only")
os.environ.setdefault("OPENROUTER_API_KEY", "test-key")

FAKE_MODELS = [
    {"id": "openai/gpt-4o", "name": "GPT-4o", "context_length": 128000, "pricing": {"prompt": "0.000005"}},
    {"id": "anthropic/claude-3-haiku", "name": "Claude 3 Haiku", "context_length": 200000, "pricing": {}},
]

FAKE_CHAT_RESPONSE = {
    "id": "gen-abc123",
    "model": "openai/gpt-4o",
    "choices": [{"message": {"role": "assistant", "content": "Hello! How can I help?"}}],
    "usage": {"prompt_tokens": 10, "completion_tokens": 8, "total_tokens": 18},
}


@pytest.fixture(autouse=True)
def fresh_db():
    db_module._conn = None
    db_module.init_db(":memory:")
    yield
    db_module.close_db()
    db_module._conn = None


@pytest_asyncio.fixture
async def client(fresh_db):
    transport = ASGITransport(app=app)
    async with AsyncClient(transport=transport, base_url="http://test") as ac:
        yield ac


async def _user_token(client):
    await client.post("/auth/register", json={"email": "user@example.com", "password": "secret123"})
    resp = await client.post("/auth/login", json={"email": "user@example.com", "password": "secret123"})
    return resp.json()["access_token"]


# ---------------------------------------------------------------------------
# GET /ai/models
# ---------------------------------------------------------------------------

async def test_list_models(client):
    token = await _user_token(client)
    with patch(
        "app.routers.ai.openrouter.list_models",
        new_callable=AsyncMock,
        return_value=FAKE_MODELS,
    ):
        resp = await client.get("/ai/models", headers={"Authorization": f"Bearer {token}"})

    assert resp.status_code == 200
    data = resp.json()
    assert len(data) == 2
    assert data[0]["id"] == "openai/gpt-4o"
    assert data[1]["name"] == "Claude 3 Haiku"


async def test_list_models_unauthenticated(client):
    resp = await client.get("/ai/models")
    assert resp.status_code == 401


async def test_list_models_upstream_error(client):
    token = await _user_token(client)
    with patch(
        "app.routers.ai.openrouter.list_models",
        new_callable=AsyncMock,
        side_effect=Exception("Connection refused"),
    ):
        resp = await client.get("/ai/models", headers={"Authorization": f"Bearer {token}"})

    assert resp.status_code == 502
    assert "OpenRouter error" in resp.json()["detail"]


# ---------------------------------------------------------------------------
# POST /ai/chat
# ---------------------------------------------------------------------------

async def test_chat_success(client):
    token = await _user_token(client)
    with patch(
        "app.routers.ai.openrouter.chat_completion",
        new_callable=AsyncMock,
        return_value=FAKE_CHAT_RESPONSE,
    ):
        resp = await client.post(
            "/ai/chat",
            json={
                "model": "openai/gpt-4o",
                "messages": [{"role": "user", "content": "Hello"}],
            },
            headers={"Authorization": f"Bearer {token}"},
        )

    assert resp.status_code == 200
    data = resp.json()
    assert data["id"] == "gen-abc123"
    assert data["model"] == "openai/gpt-4o"
    assert data["content"] == "Hello! How can I help?"
    assert data["usage"]["total_tokens"] == 18


async def test_chat_passes_parameters(client):
    token = await _user_token(client)
    mock = AsyncMock(return_value=FAKE_CHAT_RESPONSE)
    with patch("app.routers.ai.openrouter.chat_completion", new_callable=AsyncMock, return_value=FAKE_CHAT_RESPONSE) as mock:
        await client.post(
            "/ai/chat",
            json={
                "model": "anthropic/claude-3-haiku",
                "messages": [{"role": "user", "content": "Hi"}],
                "temperature": 0.3,
                "max_tokens": 512,
            },
            headers={"Authorization": f"Bearer {token}"},
        )
    mock.assert_called_once_with(
        model="anthropic/claude-3-haiku",
        messages=[{"role": "user", "content": "Hi"}],
        temperature=0.3,
        max_tokens=512,
    )


async def test_chat_unauthenticated(client):
    resp = await client.post(
        "/ai/chat",
        json={"model": "openai/gpt-4o", "messages": [{"role": "user", "content": "Hi"}]},
    )
    assert resp.status_code == 401


async def test_chat_upstream_error(client):
    token = await _user_token(client)
    with patch(
        "app.routers.ai.openrouter.chat_completion",
        new_callable=AsyncMock,
        side_effect=Exception("timeout"),
    ):
        resp = await client.post(
            "/ai/chat",
            json={"model": "openai/gpt-4o", "messages": [{"role": "user", "content": "Hi"}]},
            headers={"Authorization": f"Bearer {token}"},
        )
    assert resp.status_code == 502


async def test_chat_malformed_upstream_response(client):
    token = await _user_token(client)
    with patch(
        "app.routers.ai.openrouter.chat_completion",
        new_callable=AsyncMock,
        return_value={"id": "x", "choices": []},  # empty choices
    ):
        resp = await client.post(
            "/ai/chat",
            json={"model": "openai/gpt-4o", "messages": [{"role": "user", "content": "Hi"}]},
            headers={"Authorization": f"Bearer {token}"},
        )
    assert resp.status_code == 502