from __future__ import annotations

import os
from collections.abc import AsyncIterator
from collections.abc import Iterator

import pytest
import pytest_asyncio
from fastapi.testclient import TestClient
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.fixture
def client() -> Iterator[TestClient]:
    """Provides a TestClient bound to a fresh application instance."""
    with TestClient(create_app()) as test_client:
        yield test_client


@pytest.fixture
def mcp_endpoint_url() -> str:
    """Provides the MCP endpoint URL for SDK-based client sessions."""
    return os.getenv("PERSONAL_MCP_TEST_HTTP_URL", "")


@pytest_asyncio.fixture
async def mcp_http_client() -> AsyncIterator[AsyncClient]:
    """Provides a reusable async HTTP client for MCP SDK transports."""
    async with AsyncClient(timeout=10.0) as http_client:
        yield http_client


@pytest_asyncio.fixture
async def mcp_session_uninitialized(
    mcp_endpoint_url: str,
    mcp_http_client: AsyncClient,
) -> AsyncIterator[ClientSession]:
    """Provides a connected MCP SDK session before initialize is called."""
    if not mcp_endpoint_url:
        pytest.skip("Set PERSONAL_MCP_TEST_HTTP_URL to run SDK-backed MCP endpoint tests.")

    async with (
        streamable_http_client(
            mcp_endpoint_url,
            http_client=mcp_http_client,
        ) as (read_stream, write_stream, _),
        ClientSession(read_stream, write_stream) as session,
    ):
        yield session


@pytest_asyncio.fixture
async def mcp_session(
    mcp_session_uninitialized: ClientSession,
) -> AsyncIterator[ClientSession]:
    """Provides an initialized MCP SDK session ready for endpoint calls."""
    await mcp_session_uninitialized.initialize()
    yield mcp_session_uninitialized