from __future__ import annotations

from collections.abc import AsyncIterator
from contextlib import asynccontextmanager

import pytest
import pytest_asyncio
from httpx import ASGITransport
from httpx import AsyncClient
from mcp import ClientSession
from mcp.client.streamable_http import streamable_http_client

from personal_mcp.web.app import create_app


@pytest_asyncio.fixture
async def client() -> AsyncIterator[AsyncClient]:
    """Provides an AsyncClient bound to a fresh application instance."""
    app = create_app()
    async with AsyncClient(
        transport=ASGITransport(app=app),
        base_url="http://testserver",
        timeout=10.0,
    ) as test_client:
        yield test_client


@pytest.fixture
def mcp_session_factory():
    """Provides an in-process context manager factory for MCP SDK sessions."""

    @asynccontextmanager
    async def create_session(*, initialize: bool = True) -> AsyncIterator[ClientSession]:
        app = create_app()
        mcp_url = f"http://testserver{app.state.settings.mounts.mcp}"
        async with (
            app.router.lifespan_context(app),
            AsyncClient(
                transport=ASGITransport(app=app),
                base_url="http://testserver",
                timeout=10.0,
            ) as http_client,
            streamable_http_client(
                mcp_url,
                http_client=http_client,
            ) as (read_stream, write_stream, _),
            ClientSession(read_stream, write_stream) as session,
        ):
            if initialize:
                await session.initialize()
            yield session

    return create_session