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

public class BallSpawner : MonoBehaviour
{
    public GameObject basicBallPrefab;

    public GameObject nuclearBallPrefab;

    public GameObject glassBallPrefab;

    public GameObject eyeBallPrefab;

    public GameObject oozeBallPrefab;

    public GameObject fruitBallPrefab;

    public GameObject gameBoard;

    private static WaitForSeconds _waitForSeconds0_5 = new WaitForSeconds(0.5f);

    private Queue<System.Action> ballQueue = new Queue<System.Action>();

    private Queue<GameObject> balls = new Queue<GameObject>();

    // Start is called once before the first execution of Update after the MonoBehaviour is created
    void Start()
    {
        int currentLevel = PlayerPrefs.GetInt("CurrentLevel");

        ballQueue.Enqueue(() => SpawnBall(basicBallPrefab));
        ballQueue.Enqueue(() => SpawnBall(basicBallPrefab));
        ballQueue.Enqueue(() => SpawnBall(basicBallPrefab));
        ballQueue.Enqueue(() => SpawnBall(fruitBallPrefab));
        ballQueue.Enqueue(() => SpawnBall(fruitBallPrefab));
        ballQueue.Enqueue(() => SpawnBall(oozeBallPrefab));

        StartCoroutine(SpawnBalls());
    }

    private void SpawnBall(GameObject ballPrefab)
    {
        if (ballPrefab == null || gameBoard == null)
        {
            Debug.LogWarning("BallSpawner: Missing ballPrefab or gameBoard reference.");
            return;
        }

        Vector3 spawnPosition = GetRandomPositionInsideGameBoard();
        var newBall = Instantiate(ballPrefab, spawnPosition, Quaternion.identity);

        balls.Enqueue(newBall);
    }

    private Vector3 GetRandomPositionInsideGameBoard()
    {
        Bounds bounds;

        Collider2D collider2D = gameBoard.GetComponent<Collider2D>();
        if (collider2D != null)
        {
            bounds = collider2D.bounds;
        }
        else
        {
            Renderer boardRenderer = gameBoard.GetComponent<Renderer>();
            if (boardRenderer == null)
            {
                Debug.LogWarning("BallSpawner: gameBoard needs a Collider2D or Renderer to read bounds.");
                return gameBoard.transform.position;
            }

            bounds = boardRenderer.bounds;
        }

        const float edgeInset = 0.05f;
        float randomX = Random.Range(bounds.min.x + edgeInset, bounds.max.x - edgeInset);
        float randomY = Random.Range(bounds.min.y + edgeInset, bounds.max.y - edgeInset);

        return new Vector3(randomX, randomY, gameBoard.transform.position.z);
    }

    private IEnumerator SpawnBalls()
    {
        while (ballQueue.Count > 0)
        {
            System.Action spawnAction = ballQueue.Dequeue();
            spawnAction.Invoke();
            yield return _waitForSeconds0_5;
        }

        // Disable collision between existing balls of certain types.
        // Only basic balls and fruit balls will collide with each other, while ooze,
        // nuclear, glass, and eye balls will not collide with any other balls.
        // As an exception, glass balls will collide with other glass balls.
        foreach (var ball in balls)
        {
            foreach (var otherBall in balls)
            {
                if (ball == otherBall) continue;

                bool ballIsBasicOrFruit = ball.CompareTag("BasicBall") || ball.CompareTag("FruitBall");
                bool otherIsBasicOrFruit = otherBall.CompareTag("BasicBall") || otherBall.CompareTag("FruitBall");
                bool bothAreGlass = ball.CompareTag("GlassBall") && otherBall.CompareTag("GlassBall");

                bool shouldCollide = (ballIsBasicOrFruit && otherIsBasicOrFruit) || bothAreGlass;

                if (!shouldCollide)
                {
                    Physics2D.IgnoreCollision(
                        ball.GetComponent<Collider2D>(), 
                        otherBall.GetComponent<Collider2D>(), 
                        true
                    );
                }
            }
        }
    }
}