Ball.cs

using System.Collections;
using System.Collections.Generic;
using System.Net;
using Unity.Mathematics;
using UnityEngine;
using UnityEngine.UI;
using Random = UnityEngine.Random;

public class Ball : MonoBehaviour
{
    public GameFieldManager gfm;
    public Color color;
    public Vector2 position;

    public Image image;
    public BoxCollider2D boxCollider2D;
    public RectTransform rectTransform;
    public Button button;

    private void Awake()
    {
        gfm = GameObject.Find("/GameManager").GetComponent<GameFieldManager>();
        image = GetComponent<Image>();
        boxCollider2D = GetComponent<BoxCollider2D>();
        rectTransform = GetComponent<RectTransform>();
        button = GetComponent<Button>();
    }

    private void Start()
    {
        OnEnable();
        boxCollider2D.offset = new Vector2(gfm.ballSize.x / -2, gfm.ballSize.y / 2);
        boxCollider2D.size = gfm.ballSize;
        button.onClick.AddListener(delegate { gfm.CollectBallsToDestroy(this); });
    }

    private void OnEnable()
    {
        image.color = gfm.colors[Random.Range(0, gfm.colors.Count)];
        color = image.color;
        position = new Vector2(Mathf.Round(rectTransform.anchoredPosition.x / gfm.ballSize.x), Mathf.Round(rectTransform.anchoredPosition.y / gfm.ballSize.y));
        name = string.Format("{0}/{1} Ball", position.x, position.y);
    }

    public List<Ball> GetBallsAround()
    {
        List<Ball> ballsList = new List<Ball>();

        Collider2D[] hit = Physics2D.OverlapBoxAll(new Vector2(transform.position.x - (gfm.ballSize.x / 2), transform.position.y + (gfm.ballSize.y / 2)), gfm.ballSize * 1.2f, 0);
        foreach (Collider2D item in hit)
        {
            Ball ball = item.GetComponent<Ball>();
            if ((ball.position + Vector2.up == position ||
                 ball.position + Vector2.down == position ||
                 ball.position + Vector2.left == position ||
                 ball.position + Vector2.right == position) && ball.color == color)
            {
                ballsList.Add(ball);
            }
        }
        return ballsList;
    }

    public void MoveDown()
    {
        if (position.y > 0)
        {
            RaycastHit2D hit = Physics2D.Raycast(transform.position + Vector3.down + Vector3.left, Vector2.down, gfm.gameFieldSize.y);
            Vector2 posToMove = new Vector2(-1, -1);
            if (hit)
            {
                if (hit.transform.gameObject.GetComponent<Ball>().position.y + 1 != position.y)
                {
                    posToMove = hit.transform.gameObject.GetComponent<Ball>().position + Vector2.up ;
                }
            }
            else
            {
                posToMove = new Vector2(position.x, 0);
            }
            if (posToMove != new Vector2(-1, -1))
            {
                Move(posToMove);
            }
        }
    }

    public void MoveRight()
    {
        if (position.x < 0)
        {
            RaycastHit2D hit = Physics2D.Raycast(transform.position + Vector3.up + Vector3.right, Vector2.right, gfm.gameFieldSize.x);
            Vector2 posToMove = new Vector2(-1, -1);
            if (hit)
            {
                if (hit.transform.gameObject.GetComponent<Ball>().position.x - 1 != position.x)
                {
                    posToMove = hit.transform.gameObject.GetComponent<Ball>().position + Vector2.left;
                }
            }
            else
            {
                posToMove = new Vector2(0, position.y);
            }
            if (posToMove != new Vector2(-1, -1))
            {
                Move(posToMove);
            }
        }
    }

    private void Move(Vector2 pos)
    {
        //Debug.Log(string.Format("Move {0} to {1}", position, pos));
        rectTransform.anchoredPosition = pos * gfm.ballSize;
        position = pos;
        name = string.Format("{0}/{1} Ball", position.x, position.y);
    }
}