using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using System;

public class TimeManager : MonoBehaviour {
    private List<timeInstance> times;
    private bool isRewinding;
    private Rigidbody rb;

    private Vector3 VelAtStopRewind;

    // Use this for initialization
    void Start()
    {
        times = new List<timeInstance>();
        if (transform.GetComponent<Rigidbody>() != null)
        {
            rb = transform.GetComponent<Rigidbody>();
        }
    }
    void Update()
    {
        if (Input.GetKeyDown(KeyCode.Return))
        {
            setIsRewinding();
        }
        if (Input.GetKeyUp(KeyCode.Return))
        {
            setNotRewinding();
        }
    }

    void FixedUpdate()
    {
        if (isRewinding)
        {
            rewind1step();
        } else
        {
            addToTimes();
        }
    }
    void setIsRewinding()
    {
        isRewinding = true;
        if (rb != null)
        {
            rb.isKinematic = true;
        }
    }
    void setNotRewinding()
    {
        isRewinding = false;
        if (rb != null)
        {
            rb.isKinematic = false;
            rb.velocity = VelAtStopRewind;
        }
    }


    void addToTimes()
    {
        if (rb != null)
        {
            times.Insert(0, new timeInstance(transform.localPosition, transform.localRotation, rb.velocity));
        }
        else
        {
            times.Insert(0, new timeInstance(transform.localPosition, transform.localRotation));
        }
    }

    void rewind1step()
    {
        if (times.Count < 1)
        {
            setNotRewinding();
            return;
        }
        timeInstance temp = times[0];
        times.RemoveAt(0);
        transform.localPosition = temp.position;
        transform.localRotation = temp.rotation;

        if (rb != null)
        {
            VelAtStopRewind = temp.velocity;
        }
    }
}
[Serializable]
public struct timeInstance
{
    public Vector3 position;
    public Quaternion rotation;
    public Vector3 velocity;
    public timeInstance(Vector3 _pos, Quaternion _rot, Vector3 _velocity)
    {
        position = _pos;
        rotation = _rot;
        velocity = _velocity;
    }
    public timeInstance(Vector3 _pos, Quaternion _rot)
    {
        position = _pos;
        rotation = _rot;
        velocity = new Vector3(0,0,0);
    }
}