"""Actual loopback WebSocket checks; no application, database or external calls."""
import importlib.machinery
import importlib.util
from pathlib import Path
import socketserver
import threading
import unittest


HAS_TRANSPORT = all(importlib.util.find_spec(name) for name in ("uvicorn", "wsproto"))


@unittest.skipUnless(HAS_TRANSPORT, "Install pinned uvicorn and wsproto to run the transport tests")
class WebSocketHealthcheckTests(unittest.TestCase):
    @classmethod
    def setUpClass(cls):
        path = Path(__file__).resolve().parents[1] / "eusrr-deploy-healthcheck"
        loader = importlib.machinery.SourceFileLoader("deploy_healthcheck", str(path))
        cls.probe = importlib.util.module_from_spec(importlib.util.spec_from_loader(loader.name, loader))
        loader.exec_module(cls.probe)

    def test_actual_uvicorn_101_and_asgi_frame(self):
        self.probe.check_transport()

    def run_rejection_server(self, status):
        class Handler(socketserver.BaseRequestHandler):
            def handle(self):
                self.request.recv(4096)
                self.request.sendall(
                    f"HTTP/1.1 {status} Response\r\nContent-Length: 0\r\nConnection: close\r\n\r\n".encode()
                )

        server = socketserver.TCPServer(("127.0.0.1", 0), Handler)
        thread = threading.Thread(target=server.handle_request, daemon=True)
        thread.start()
        self.addCleanup(server.server_close)
        self.addCleanup(lambda: thread.join(timeout=5))
        return server.server_address[1]

    def test_anonymous_rejection_is_expected(self):
        self.probe.handshake(self.run_rejection_server(403), "/ws/", 403)

    def test_http_fallback_404_does_not_pass(self):
        with self.assertRaisesRegex(RuntimeError, "Unexpected WebSocket HTTP status"):
            self.probe.handshake(self.run_rejection_server(404), "/ws/", 403)

    def test_bogus_101_without_accept_does_not_pass(self):
        with self.assertRaisesRegex(RuntimeError, "Invalid WebSocket upgrade"):
            self.probe.handshake(self.run_rejection_server(101), "/", 101)


if __name__ == "__main__":
    unittest.main()