// Copyright 2019-2021 Robotec.ai.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

using System;
using ROS2;
using sensor_msgs.msg;
using Unity.Collections.LowLevel.Unsafe;
using UnityEngine;

namespace ZC
{

/// <summary>
/// An example class provided for testing of basic ROS2 communication
/// </summary>
public class ROS2ListenerExample : MonoBehaviour
{
    private ROS2UnityComponent ros2Unity;
    private ROS2Node ros2Node;
    private ISubscription<PointCloud2> chatter_sub;

    void Start()
    {
        ros2Unity = GetComponent<ROS2UnityComponent>();
    }

    void Update()
    {
        if (ros2Node == null && ros2Unity.Ok())
        {
            ros2Node = ros2Unity.CreateNode("ROS2UnityListenerNode");
            chatter_sub = ros2Node.CreateSubscription<PointCloud2>(
                "chatter_PointCloud2", msg =>
                {
                    unsafe
                    {
                        var objData = msg.Data;
                        var pinGCArrayAndGetDataAddress = UnsafeUtility.PinGCArrayAndGetDataAddress(objData, out var handle);
                        try
                        {
                            var gcArrayAndGetDataAddress = (long*)pinGCArrayAndGetDataAddress;
                            var ticks = *gcArrayAndGetDataAddress;
                            var dateTime = new DateTime(ticks);
                            Debug.Log($"re:{DateTime.Now:HH:mm:ss.fff}");
                            Debug.Log($"se:{dateTime:HH:mm:ss.fff}");
                        }
                        finally
                        {
                            UnsafeUtility.ReleaseGCObject(handle);
                        }
                    }
                });
        }
    }
}

}  // namespace ROS2