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

public class GameController : MonoBehaviour
{
    private static GameController instance;
    [SerializeField]
    private string startScene, mainScene, endScene;
    [SerializeField]
    private float fadeSpeed;
    [SerializeField]
    private Image fadeImg;
    [SerializeField]
    private TMP_Text coinText;
    private Coroutine fadeCoroutine;
    private int coinAmount = 0;
    public int CoinAmount{get=>coinAmount;}
    public static GameController Instance{
        get{
            if(instance is null)Debug.LogError("Game controller is null");
            return instance;
        }
    }

    private void Awake() {
        if(GameController.Instance is null){
            instance = this;
            DontDestroyOnLoad(this.gameObject);
            SceneManager.activeSceneChanged += ChangedScene;
            coinText.text = "0";
            Debug.Log("Awake");
            if(!SceneManager.GetActiveScene().name.Equals(mainScene)){
                coinText.gameObject.SetActive(false);
            }else{
                coinText.gameObject.SetActive(true);
            }
        }else{
            Destroy(this.gameObject);
        }
        
    }

    public void AddCoins(int amount){
        //This should not be like this. Collectible should call the player that hit it and add to their amount
        coinAmount += amount;
        coinText.text = coinAmount.ToString();
    }
    

    public void StartGame(){
        fadeCoroutine = StartCoroutine(FadeToBlack(mainScene, true,fadeSpeed));
    }

    public void EndGame(){
        Debug.Log("Game is over");
        fadeCoroutine = StartCoroutine(FadeToBlack(endScene, true,fadeSpeed));
    }

    public void QuitGame(){
        //fadeCoroutine = StartCoroutine(FadeToBlack(true,fadeTimer));
        Application.Quit();
    }

    public void Options(){
        //fadeCoroutine = StartCoroutine(FadeToBlack(true,fadeTimer));
        Debug.Log("Clicked options");
    }

    public void MainMenu(){
        fadeCoroutine = StartCoroutine(FadeToBlack(startScene, true,fadeSpeed));
    }

    private void ChangedScene(Scene curr, Scene next){
        fadeCoroutine = StartCoroutine(FadeToBlack(string.Empty, false, fadeSpeed));
        if(!next.name.Equals(mainScene)){
            coinText.gameObject.SetActive(false);
        }else{
            coinText.gameObject.SetActive(true);
        }
    }

    public IEnumerator FadeToBlack(string sceneToLoad,bool fadeToBlack = true, float fadeSpeed = 2.5f){
        Color imgColor = fadeImg.color;
        float fadeAmount;
        if(fadeToBlack){
            while(fadeImg.color.a < 1){
                fadeAmount = imgColor.a + (fadeSpeed * Time.deltaTime);
                imgColor = new Color(imgColor.r, imgColor.g, imgColor.b, fadeAmount);
                fadeImg.color = imgColor;
                yield return null;
            }
            SceneManager.LoadScene(sceneToLoad);
        }else{
            while(fadeImg.color.a > 0){
                fadeAmount = imgColor.a - (fadeSpeed * Time.deltaTime);
                imgColor = new Color(imgColor.r, imgColor.g, imgColor.b, fadeAmount);
                fadeImg.color = imgColor;
                yield return null;
            }
        }
    }
}