import json
import sys
from collections.abc import Generator

import pytest
import uvicorn
from mcp.types import TextContent, TextResourceContents

from fastmcp.client import Client
from fastmcp.client.transports import StreamableHttpTransport
from fastmcp.server.dependencies import get_http_request
from fastmcp.server.server import FastMCP
from fastmcp.utilities.tests import run_server_in_process


def fastmcp_server():
    server = FastMCP()

    # Add a tool
    @server.tool()
    def get_headers_tool() -> dict[str, str]:
        """Get the HTTP headers from the request."""
        request = get_http_request()

        return dict(request.headers)

    @server.resource(uri="request://headers")
    async def get_headers_resource() -> dict[str, str]:
        request = get_http_request()

        return dict(request.headers)

    # Add a prompt
    @server.prompt()
    def get_headers_prompt() -> str:
        """Get the HTTP headers from the request."""
        request = get_http_request()

        return json.dumps(dict(request.headers))

    return server


def run_server(host: str, port: int) -> None:
    try:
        app = fastmcp_server().http_app()
        server = uvicorn.Server(
            config=uvicorn.Config(
                app=app,
                host=host,
                port=port,
                log_level="error",
                lifespan="on",
            )
        )
        server.run()
    except Exception as e:
        print(f"Server error: {e}")
        sys.exit(1)
    sys.exit(0)


@pytest.fixture(autouse=True, scope="module")
def sse_server() -> Generator[str, None, None]:
    with run_server_in_process(run_server) as url:
        yield f"{url}/mcp"


async def test_http_headers_resource(sse_server: str):
    """Test getting HTTP headers from the server."""
    async with Client(
        transport=StreamableHttpTransport(sse_server, headers={"X-DEMO-HEADER": "ABC"})
    ) as client:
        raw_result = await client.read_resource("request://headers")
        assert isinstance(raw_result[0], TextResourceContents)
        json_result = json.loads(raw_result[0].text)
        assert "x-demo-header" in json_result
        assert json_result["x-demo-header"] == "ABC"


async def test_http_headers_tool(sse_server: str):
    """Test getting HTTP headers from the server."""
    async with Client(
        transport=StreamableHttpTransport(sse_server, headers={"X-DEMO-HEADER": "ABC"})
    ) as client:
        result = await client.call_tool("get_headers_tool")
        assert isinstance(result[0], TextContent)
        json_result = json.loads(result[0].text)
        assert "x-demo-header" in json_result
        assert json_result["x-demo-header"] == "ABC"


async def test_http_headers_prompt(sse_server: str):
    """Test getting HTTP headers from the server."""
    async with Client(
        transport=StreamableHttpTransport(sse_server, headers={"X-DEMO-HEADER": "ABC"})
    ) as client:
        result = await client.get_prompt("get_headers_prompt")
        assert isinstance(result.messages[0].content, TextContent)
        json_result = json.loads(result.messages[0].content.text)
        assert "x-demo-header" in json_result
        assert json_result["x-demo-header"] == "ABC"