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

[NetworkSettings(channel = 0, sendInterval = 0)]
public class CarClient : NetworkBehaviour {

	public float delay = 2;

	private float timeAlive = 0;
	private StateBuffer stateBuffer;

	public GameObject brakeLights;
	public Transform explosion;
	public Transform fire;

	private Transform thisFire;

	private bool alreadyOnFire = false;
	private bool isDead = false;
	
	private void Start ()
	{
		if (isClient)
		{
			
		}
	}

	public void FixedUpdate ()
	{
		if(isClient)
		{
			if(stateBuffer == null)
				stateBuffer = new StateBuffer(delay);

			if (stateBuffer.CanStartInterpolating())
			{
				//Pontosabb, mint a Time.time
				timeAlive += Time.deltaTime;


				stateBuffer.Interpolate(timeAlive);

				if (isDead)
				{
					transform.position = Vector3.zero;
					return;
				}

				ChangeBrakeLights(stateBuffer.IsBraking());

				if(stateBuffer.ShouldExplode() && !alreadyOnFire)
				{
					thisFire = Instantiate(fire, transform.position, transform.rotation);
					alreadyOnFire = true;
				}

				if (stateBuffer.ShouldDie())
				{
					Instantiate(explosion, transform.position, transform.rotation);
					Destroy(thisFire.gameObject);
					isDead = true;
				}

				transform.position = stateBuffer.GetCurrentPosition();
				transform.rotation = stateBuffer.GetCurrentRotation();
			}
		}
	}


	//A féklámpa ki/be kapcsolására
	private void ChangeBrakeLights (bool newState)
	{
		for (int a = 0; a < brakeLights.transform.childCount; a++)
			brakeLights.transform.GetChild(a).gameObject.SetActive(newState);
	}

	//RPC: Remote procedure call, QoS: reliable sequenced
	[ClientRpc(channel = 0)]
	public void RpcDecodeBits (ulong newStateBits)
	{
		if (stateBuffer == null)
			stateBuffer = new StateBuffer(delay);
		CompressedStateFrame compressedStateFrame = new CompressedStateFrame(newStateBits);
		StateFrame newStateFrame = compressedStateFrame.GetDecodedStateFrame(transform);
		stateBuffer.AddFrame(ref newStateFrame);
	}
}

public class CompressedStateFrame
{
	private ulong stateBits;
	public CompressedStateFrame(ulong stateBits)
	{
		this.stateBits = stateBits;
	}

	public StateFrame GetDecodedStateFrame(Transform carTransform)
	{
		StateFrame decodedFrame = new StateFrame();

		decodedFrame.isBraking = TakeAwayLastBitAsBool();

		float xPosition = TakeAwayLastNbitsAsFixed(12, 1f / 16);
		float zPosition = TakeAwayLastNbitsAsFixed(12, 1f / 16);
		decodedFrame.position = new Vector3(xPosition, carTransform.position.y, zPosition);

		float rotation = TakeAwayLastNbitsAsFixed(7, 360f / 127);
		decodedFrame.direction = Quaternion.AngleAxis(rotation, carTransform.up);

		decodedFrame.shouldExplode = TakeAwayLastBitAsBool();
		decodedFrame.shouldDie = TakeAwayLastBitAsBool();
		decodedFrame.isTurning = TakeAwayLastBitAsBool();

		decodedFrame.serverStartTime = (float)stateBits / 1000;

		return decodedFrame;
	}

	private bool TakeAwayLastBitAsBool ()
	{
		bool lastBit = ( stateBits & 1 ) == 1;
		stateBits >>= 1;
		return lastBit;
	}
	private float TakeAwayLastNbitsAsFixed (int n, float multiplier)
	{
		return (float)TakeAwayLastNbitsAsUlong(n) * multiplier;
	}
	private ulong TakeAwayLastNbitsAsUlong (int n)
	{
		ulong mask = (ulong)( 1 << n ) - 1;
		ulong lastNbits = stateBits & mask;
		stateBits >>= n;
		return lastNbits;
	}

}

//Egy autó egy állapota, tekinthetőek keyframeeknek, amik között lineárisan készítünk kitöltő állapotokat készítünk
[System.Serializable]
public class StateFrame
{
	//client mikor kezdte el?
	public float clientStartTime;
	//szerver mikor kezdte el?
	public float serverStartTime;
	//Az időket az adott autó spawnolásától mérjük.

	public Vector3 position;
	public Quaternion direction;

	public bool isBraking;
	public bool isTurning;
	public bool shouldExplode;
	public bool shouldDie;
}

//Az autó állapotframejei itt tárolódnak
[System.Serializable]
public class StateBuffer
{
	private float timeOfLastUpdate;

	private float delay;

	private float intervalLengthClient;
	private float intervalLengthServer;
	private float qBetweenFrames;

	private bool isInValidState = true;

	private bool hasStarted = false;

	//jelenleg ez a két frame közt van
	private StateFrame before;
	private StateFrame after;
	//Egy autó jövője delay mp-re előre
	private Queue next;

	public StateBuffer (float delay)
	{
		this.delay = delay;
		next = new Queue();
	}

	public void AddFrame (ref StateFrame newFrame)
	{
		//A visszajátszás sebessége kiszámolásáshoz fontos tudni
		timeOfLastUpdate = newFrame.serverStartTime;

		if (before == null)
		{
			before = newFrame;
			before.clientStartTime = 0;
		}

		else if (after == null)
			after = newFrame;
		else
			next.Enqueue(newFrame);
	}

	public bool CanStartInterpolating ()
	{
		if (before != null && after != null)
			hasStarted = true;
		return hasStarted;
	}

	public void Interpolate (float timeAlive)
	{
		do
		{
			isInValidState = true;

			intervalLengthClient = timeAlive - before.clientStartTime;
			intervalLengthServer = after.serverStartTime - before.serverStartTime;

			CompansateIfOutOfSync();

			if (NeedToChangeFrame())
			{

				try
				{
					ChangeFrame(timeAlive);
				}
				catch (System.Exception)
				{
					isInValidState = false;
					return;
				}					
			}

		} while (NeedToChangeFrame());

		qBetweenFrames = intervalLengthClient / intervalLengthServer;
	}

	private void CompansateIfOutOfSync()
	{
		intervalLengthServer /= ( timeOfLastUpdate - before.serverStartTime ) / delay;
	}
	private bool NeedToChangeFrame()
	{
		return intervalLengthClient > intervalLengthServer || intervalLengthServer == 0;
	}

	private void ChangeFrame (float timeAlive)
	{
		before = after;
		before.clientStartTime = timeAlive - ( intervalLengthClient - intervalLengthServer );
		after = (StateFrame)next.Dequeue();
	}

	public bool ShouldExplode()
	{
		return before.shouldExplode;
	}
	public bool ShouldDie()
	{
		return before.shouldDie;
	}
	public bool IsBraking ()
	{
		return before.isBraking;
	}
	public Vector3 GetCurrentPosition()
	{
		if (!isInValidState) return Vector3.zero;

		if (Vector3.Magnitude(after.position - before.position) > 20)
		{
			Debug.Log("jump " + before.position + ", " + after.position);
			return after.position;
		}

		if (before.isTurning)
			return Vector3.Slerp(before.position, after.position, qBetweenFrames);
		else
			return Vector3.Lerp(before.position, after.position, qBetweenFrames);
	}

	public Quaternion GetCurrentRotation()
	{
		if (!isInValidState) return Quaternion.identity;
		return Quaternion.Slerp(before.direction, after.direction, qBetweenFrames);
	}
}