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

//Handle Objects in Queue
public class ObjectQ : MonoBehaviour
{
    //all objects in the Q(ueue) are stored here
    [SerializeField]
    private List<QableObject> queue = new List<QableObject>();
    [SerializeField]
    private Material material;

    private QableObject currentObject = null;
    private int currentIndex = 0;
    private State currentState = State.Changing;
    

    //switch to next or previous object in Q
    public void Change(bool previous = false)
    {
        if(queue.Count < 2 || currentState != State.ViewMode)
            return;

        currentIndex = previous ? currentIndex - 1 : currentIndex + 1;
        currentIndex = (currentIndex + queue.Count) % queue.Count;
        StartCoroutine(ShowNext());
        currentState = State.Changing;
    }

    //add Object to Q
    public void Add(GameObject gameObject)
    {
        var o = gameObject.AddComponent<QableObject>();
        gameObject.transform.SetParent(transform);
        gameObject.transform.position = transform.position;
        o.renderer.material = material;

        queue.Add(o);
        
        //if no object is currently visible then show the first object in Q
        if(currentObject == null)
            StartCoroutine(ShowNext());
    }

    //Show next object from currentIndex
    private IEnumerator ShowNext()
    {
        if(currentObject != null)
            yield return StartCoroutine(currentObject.Dissolve());
        
        currentObject = queue[currentIndex];
        StartCoroutine(currentObject.Dissolve(true));
        currentState = State.ViewMode;
    }

    
    //States of ObjectQ
    public enum State
    {
        ViewMode,
        Changing
    }
    
}