using UnityEngine;
using UnityEngine.UI;
using UnityEngine.AI;
using System.Collections.Generic;
using System.IO;
using System;

[DefaultExecutionOrder(40)]
[RequireComponent(typeof(InstantiatePrefab), typeof(WriteInCSV), typeof(ReadFromCSV))]
public class WalkLerpPlayback : MonoBehaviour
{
    // Waypoints and Rotations
    public Tuple<List<float>, List<Vector3>, List<Quaternion>, List<float>>[][] timePosRotList;

    // Animation
    private const string isWalking = "isWalking";
    private const string isGrabbing = "isGrabbing";

    // Private Journey Settings
    private int currentStartPoint;
    private float startTime;

    // Global GameObjects
    private GameObject[][] humansGO;
    private Animator[][] humansA;

    // Playback variables
    private int[] maxIJ;
    private int indexChangeRate;
    [HideInInspector]
    public bool rewind, pause, play; //PlaybackController

    // Slider Settings
    public Slider slider;
    private float prevSliderValue;

    // Thief Settings
    private Vector3 stealHere;

    private void Start()
    {
        // Get information from InstatiatePrefab
        humansGO = gameObject.GetComponent<InstantiatePrefab>().humanGameObject;
        humansA = gameObject.GetComponent<InstantiatePrefab>().humanAnimator;
        NavMeshAgent[][] humansNMA = gameObject.GetComponent<InstantiatePrefab>().humanNavMeshAgent;
        stealHere = gameObject.GetComponent<ControllingThief>().stealHere;

        // Read from CSV file and save time, position, rotation in matrix
        int index = gameObject.GetComponent<WriteInCSV>().index;
        string dir = Directory.GetCurrentDirectory();
        string reference = @"\Assets\Data_position\Walk" + index + ".csv";
        timePosRotList = gameObject.GetComponent<ReadFromCSV>().ReadFromCSVFile(dir + reference);

        // Set initial position and rotation
        currentStartPoint = 0;
        for (int i = 0; i < humansGO.Length; ++i)
        {
            for (int j = 0; j < humansGO[i].Length; ++j)
            {
                humansGO[i][j].transform.position = timePosRotList[0][0].Item2[0]; // First entry of Position
                humansGO[i][j].transform.rotation = timePosRotList[0][0].Item3[0]; // First entry of Rotation
                // Animation Idle
                humansA[i][j].SetBool(isWalking, timePosRotList[i][j].Item4[currentStartPoint] > 0.01f);

                humansNMA[i][j].enabled = false;
            }
        }

        // Set the Slider settings
        if (slider == null)
        {
            Debug.Log("No Slider instance attached");
            return;
        }
        maxIJ = GetHumanWithLongestScreenTime();
        float maxTime = (float) Math.Round(timePosRotList[maxIJ[0]][maxIJ[1]].Item1[timePosRotList[maxIJ[0]][maxIJ[1]].Item1.Count - 1], 2);
        slider.minValue = 0;
        slider.maxValue =  (maxTime / Time.deltaTime);
        slider.wholeNumbers = true;
        prevSliderValue = slider.value;
        
        SetTransform(currentStartPoint);
        currentStartPoint++;
        slider.value = currentStartPoint;
        startTime = Time.time;
    }

    private void FixedUpdate()
    {
        if (pause)
            indexChangeRate = 0;
        if (play)
            indexChangeRate = 1;
        if (rewind)
            indexChangeRate = -1;

        if (play || rewind)
        {
            if ((currentStartPoint + indexChangeRate) < timePosRotList[maxIJ[0]][maxIJ[1]].Item2.Count && (currentStartPoint + indexChangeRate) >= 0)
            {
                if(slider.value - prevSliderValue == -1 || slider.value - prevSliderValue == 0 || slider.value - prevSliderValue == 1) // rewind || play
                {
                    prevSliderValue = slider.value;
                    currentStartPoint += indexChangeRate;
                    slider.value = currentStartPoint;
                }
                else
                {
                    prevSliderValue = slider.value;
                    currentStartPoint = (int) slider.value;
                }
                SetTransform(currentStartPoint);
            }
            else if(slider.value - prevSliderValue != -1|| slider.value - prevSliderValue != 0 || slider.value - prevSliderValue != 1)
            {
                currentStartPoint = (int) slider.value;
            }
        }
        else
        {
            // upper else-Statement only for pause
            if (slider.value - prevSliderValue != 0)
            {
                //prevSliderValue = slider.value;
                currentStartPoint = (int) slider.value;
            }

            for (int i = 0; i < humansGO.Length; ++i)
            {
                for (int j = 0; j < humansGO[i].Length; ++j)
                {
                    if(currentStartPoint < timePosRotList[i][j].Item2.Count)
                    {
                        humansGO[i][j].transform.position = timePosRotList[i][j].Item2[currentStartPoint]; // First entry of Position
                        humansGO[i][j].transform.rotation = timePosRotList[i][j].Item3[currentStartPoint]; // First entry of Rotation
                        
                        humansA[i][j].SetBool(isWalking, false);
                        humansA[i][j].SetBool(isGrabbing, false);
                    }
                }
            }
        }
    }

    private void SetTransform(int currentStartPoint)
    {
        for (int i = 0; i < humansGO.Length; ++i)
        {
            for (int j = 0; j < humansGO[i].Length; ++j)
            {
                // if so ArgumentOutOfRangeException
                if ((currentStartPoint + indexChangeRate) >= (timePosRotList[i][j].Item2.Count - 1) || (currentStartPoint + indexChangeRate) < 0)
                {
                    humansA[i][j].SetBool(isWalking, false);
                    continue;
                }

                Vector3 startPos = timePosRotList[i][j].Item2[currentStartPoint];
                Vector3 endPos = timePosRotList[i][j].Item2[currentStartPoint + indexChangeRate];
                Quaternion startRot = timePosRotList[i][j].Item3[currentStartPoint];
                Quaternion endRot = timePosRotList[i][j].Item3[currentStartPoint + indexChangeRate];

                float distCovered = (Time.time - startTime) * timePosRotList[i][j].Item4[currentStartPoint];
                float fracJourney = 1f;
                float journeyLength = Vector3.Distance(startPos, endPos);
                if (journeyLength != 0 && distCovered != 0) fracJourney = distCovered / journeyLength;

                // Animation Idle, if startPoint == endPoint and startRot == endRot
                //if (journeyLength <= 0 && startRot.Equals(endRot) || currentStartPoint == 0 || currentStartPoint == timePosRotList[i][j].Item2.Count)
                //{
                //    humansA[i][j].SetBool("isWalking", false);
                //}
                //else if (journeyLength > 0)
                //{
                //    humansA[i][j].SetBool("isWalking", true);
                //}
                //humansA[i][j].speed = 2*(journeyLength / 0.2f);
                humansA[i][j].SetBool(isWalking, timePosRotList[i][j].Item4[currentStartPoint] > 0.01f);
                if (Vector3.Distance(humansGO[i][j].transform.position, stealHere) <= 1.5f && timePosRotList[i][j].Item4[currentStartPoint] == 0.0f)
                    humansA[i][j].SetBool(isGrabbing, true);
                else
                    humansA[i][j].SetBool(isGrabbing, false);

                humansGO[i][j].transform.position = Vector3.Lerp(startPos, endPos, fracJourney);
                humansGO[i][j].transform.rotation = Quaternion.Lerp(startRot, endRot, fracJourney);
            }
        }
    }

    private int[] GetHumanWithLongestScreenTime()
    {
        int[] maxIJ = new int[2] { 0, 0 };
        float currentMaxTime = 0;

        for (int i = 0; i < humansGO.Length; ++i)
        {
            for (int j = 0; j < humansGO[i].Length; ++j)
            {
                if(currentMaxTime < timePosRotList[i][j].Item1.Count)
                {
                    currentMaxTime = timePosRotList[i][j].Item1.Count;
                    maxIJ[0] = i;
                    maxIJ[1] = j;
                }
            }
        }
                
        return maxIJ;
    }
}