using System.Collections.Generic;
using UnityEngine;

public class BoardFitter : MonoBehaviour
{
    [Header("Рамка")]
    [SerializeField] private SpriteRenderer boardRenderer;

    [Header("Задний фон")]
    [SerializeField] private SpriteRenderer backgroundRenderer;
    [SerializeField] private float bgHorizontalPadding = 0.78f; //лево+право
    [SerializeField] private float bgVerticalPadding = 0.68f;   //верх+низ

    [Header("Ячейки")]
    [SerializeField] private GameObject cellPrefab;
    [SerializeField] private Transform cellsRoot;
    [SerializeField] private float cellScale = 1;
    [SerializeField] private float cellOffset = 0.1f;
    [SerializeField] private float cellGroupPadding = 3f;//2 стороны сразу
    private List<GameObject> cells;

    [Header("Подготовленная позциця")]
    [SerializeField] private float stickedOffset = 2;

    public BoardConfiguration GetConfiguration()
    {
        if (cells == null)
            throw new System.NullReferenceException($"Объект не инициализирован {this}");
                
        Vector2 offset = new Vector2(cellScale + cellOffset, -(cellScale + cellOffset));

        return new BoardConfiguration(topLeft: cells[0].transform,
                                      cellOffset: offset,
                                      stickedYOffset: stickedOffset);
    }

    public void FitBoard(int columns, int rows)
    {
        columns = Mathf.Clamp(columns, 4, 8);
        rows = Mathf.Clamp(rows, 4, 8);

        ClearCells();
        GenerateCells(columns, rows);

        float groupWidth = (cellScale + cellOffset) * columns;
        float groupHeight = (cellScale + cellOffset) * rows;

        FitFrame(groupWidth, groupHeight);
        FitCellsRoot(groupWidth, groupHeight);
    }

    private void FitCellsRoot(float groupWidth, float groupHeight)
    {
        float rootX = -groupWidth / 2;
        float rootY = (groupHeight + boardRenderer.size.y - cellScale) / 2;
        cellsRoot.localPosition = new Vector3(rootX, rootY, 0);
    }

    private void FitFrame(float groupWidth, float groupHeight)
    {
        boardRenderer.size = new Vector2(groupWidth + cellGroupPadding, groupHeight + cellGroupPadding);
        backgroundRenderer.transform.localScale = new Vector3(boardRenderer.size.x - bgHorizontalPadding,
                                                              boardRenderer.size.y - bgVerticalPadding,
                                                              0);
    }

    private void GenerateCells(int columns, int rows)
    {
        cells = new List<GameObject>();
        for (int row = 0; row < rows; row++)
        {
            for (int column = 0; column < columns; column++)
            {
                var cellGO = Instantiate(cellPrefab, cellsRoot);
                var cell = cellGO.transform;

                cell.localScale = new Vector3(cellScale, cellScale, 1);

                float x = column * (cellScale + cellOffset) + cellScale / 2;
                float y = -row * (cellScale + cellOffset) - cellScale / 2;
                cell.localPosition = new Vector3(x, y, 0);

                cells.Add(cellGO);
            }
        }
    }

    private void ClearCells()
    {
        for (int i = cellsRoot.childCount - 1; i >= 0; i--)
        {
            var cell = cellsRoot.GetChild(i).gameObject;
            Destroy(cell);
        }
    }
}