# Copyright (c) 2022, NVIDIA CORPORATION & AFFILIATES, ETH Zurich, and University of Toronto
# All rights reserved.
#
# SPDX-License-Identifier: BSD-3-Clause

"""This script demonstrates how to create a simple stage in Isaac Sim with lights and a ground plane."""

"""Launch Isaac Sim Simulator first."""


import argparse

from omni.isaac.orbit.app import AppLauncher

# add argparse arguments
parser = argparse.ArgumentParser("Welcome to Orbit: Omniverse Robotics Environments!")
parser.add_argument("--headless", action="store_true", default=False, help="Force display off at all times.")
args_cli = parser.parse_args()

# launch omniverse app
app_launcher = AppLauncher(headless=args_cli.headless)
simulation_app = app_launcher.app

"""Rest everything follows."""


import omni.isaac.core.utils.prims as prim_utils
from omni.isaac.core.simulation_context import SimulationContext
from omni.isaac.core.utils.viewports import set_camera_view

import omni.isaac.orbit.utils.kit as kit_utils

"""
Main
"""


def main():
    """Spawns lights in the stage and sets the camera view."""

    # Load kit helper
    sim = SimulationContext(physics_dt=0.01, rendering_dt=0.01, backend="torch")
    # Set main camera
    set_camera_view([2.5, 2.5, 2.5], [0.0, 0.0, 0.0])

    # Spawn things into stage
    # Ground-plane
    kit_utils.create_ground_plane("/World/defaultGroundPlane")
    # Lights-1
    prim_utils.create_prim(
        "/World/Light/GreySphere",
        "SphereLight",
        translation=(4.5, 3.5, 10.0),
        attributes={"radius": 2.5, "intensity": 600.0, "color": (0.75, 0.75, 0.75)},
    )
    # Lights-2
    prim_utils.create_prim(
        "/World/Light/WhiteSphere",
        "SphereLight",
        translation=(-4.5, 3.5, 10.0),
        attributes={"radius": 2.5, "intensity": 600.0, "color": (1.0, 1.0, 1.0)},
    )

    # Play the simulator
    sim.reset()
    # Now we are ready!
    print("[INFO]: Setup complete...")

    # Simulate physics
    while simulation_app.is_running():
        # If simulation is stopped, then exit.
        if sim.is_stopped():
            break
        # If simulation is paused, then skip.
        if not sim.is_playing():
            sim.step(render=app_launcher.RENDER)
            continue
        # perform step
        sim.step(render=app_launcher.RENDER)


if __name__ == "__main__":
    # Run empty stage
    main()
    # Close the simulator
    simulation_app.close()
