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

public class LevelLoader : MonoBehaviour
{
    [SerializeField] private AnimationClip fadeAnimation = null;
    [SerializeField][Min(0)] private float loadingScreenWaitTime = 1f;

    private static Animator transition;
    private static LevelLoader instance = null;
    public static LevelLoader Instance
    {
        get { return instance; }
        set { }
    }
    private float fadeTime = 1f;

    void Awake()
    {
        // Singleton
        if (instance == null)
        {
            instance = this;
            DontDestroyOnLoad(gameObject);
            transition = GameObject.FindGameObjectWithTag("FadeCanvas").GetComponent<Animator>();
            if (fadeAnimation != null)
            {
                fadeTime = fadeAnimation.length;
            }
            SceneManager.sceneLoaded += OnLevelFinishedLoading;
        }
        else
        {
            DestroyImmediate(this);
        }
    }

    private void OnDisable()
    {
        SceneManager.sceneLoaded -= OnLevelFinishedLoading;
    }

    private void OnLevelFinishedLoading(Scene scene, LoadSceneMode loadMode)
    {
        GameObject o;
        if(o = GameObject.FindWithTag("FadeCanvas"))
        {
            if(o.TryGetComponent<Animator>(out Animator anim))
            {
                transition = anim;
            }
            
        }
    }

    public void LoadLevel(string sceneName)
    {
        StartCoroutine(LoadingRoutine(sceneName));
    }

    IEnumerator LoadingRoutine(string sceneName)
    {
        if(transition) transition.SetTrigger("Fade");
        yield return new WaitForSeconds(fadeTime);
        SceneManager.LoadScene("Loading");
        yield return new WaitForSeconds(loadingScreenWaitTime);
        SceneManager.LoadSceneAsync(sceneName);
    }
}