#!/usr/bin/env python3
"""Host smoke test for the Tactility MCP Screen Phase 1 API."""

import argparse
import json
import socket
import urllib.request


def discover(timeout: float = 2.0) -> str | None:
    sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
    sock.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1)
    sock.settimeout(timeout)
    try:
        sock.sendto(b"DISCOVER_SCREEN", ("255.255.255.255", 5000))
        data, address = sock.recvfrom(128)
        if data == b"SCREEN_IP_80":
            return address[0]
    except TimeoutError:
        return None
    finally:
        sock.close()
    return None


def rpc(ip: str, request_id: int, method: str, params: dict | None = None) -> dict:
    payload = {
        "jsonrpc": "2.0",
        "id": request_id,
        "method": method,
    }
    if params is not None:
        payload["params"] = params

    request = urllib.request.Request(
        f"http://{ip}/api/mcp",
        data=json.dumps(payload).encode(),
        headers={"Content-Type": "application/json"},
        method="POST",
    )
    with urllib.request.urlopen(request, timeout=5) as response:
        return json.loads(response.read())


def require_result(response: dict, label: str) -> None:
    if "error" in response:
        raise RuntimeError(f"{label} failed: {response['error']}")
    if "result" not in response:
        raise RuntimeError(f"{label} returned no result: {response}")


def main() -> None:
    parser = argparse.ArgumentParser()
    parser.add_argument("--ip", help="Device IP; omit to use UDP discovery")
    parser.add_argument(
        "--draw",
        action="store_true",
        help="Also clear the app canvas and draw visible test text",
    )
    args = parser.parse_args()

    ip = args.ip or discover()
    if not ip:
        raise SystemExit("MCP Screen was not discovered. Pass --ip DEVICE_IP to test directly.")

    print(f"Testing MCP Screen at {ip}")

    tools = rpc(ip, 1, "tools/list")
    require_result(tools, "tools/list")
    names = [tool["name"] for tool in tools["result"]["tools"]]
    expected = {"get_capabilities", "clear_screen", "draw_text"}
    if not expected.issubset(names):
        raise RuntimeError(f"Missing tools: {sorted(expected - set(names))}")
    print(f"tools/list: {', '.join(names)}")

    capabilities = rpc(
        ip,
        2,
        "tools/call",
        {"name": "get_capabilities", "arguments": {}},
    )
    require_result(capabilities, "get_capabilities")
    print("get_capabilities:", capabilities["result"]["content"][0]["text"])

    if args.draw:
        cleared = rpc(
            ip,
            3,
            "tools/call",
            {"name": "clear_screen", "arguments": {"color": 1}},
        )
        require_result(cleared, "clear_screen")

        drawn = rpc(
            ip,
            4,
            "tools/call",
            {
                "name": "draw_text",
                "arguments": {
                    "text": "Tactility MCP is alive",
                    "x": 20,
                    "y": 30,
                    "size": 2,
                },
            },
        )
        require_result(drawn, "draw_text")
        print("Visible draw test sent.")

    print("Phase 1 smoke test passed.")


if __name__ == "__main__":
    main()