from __future__ import annotations
from typing import Any

class SimulatorStub:
    """Tiny stub to emulate a Gazebo/ROS-style simulator interface."""
    def __init__(self) -> None:
        self.connected = False

    def connect(self) -> None:
        self.connected = True

    def run(self, scene: str, params: dict[str, Any] | None = None) -> dict[str, Any]:
        if not self.connected:
            raise RuntimeError("Simulator not connected")
        # Return a minimal synthetic result
        return {"scene": scene, "params": params or {}, "status": "ok"}