using System.Collections.Generic;
using UnityEngine;

public class LevelGrid : MonoBehaviour {
    [SerializeField] private Transform GridDebugObjectPrefab;

    private GridSystem gridSystem;

    public static LevelGrid Instance { get; private set; }

    private void Awake() {
        if (Instance is not null) {
            Debug.LogError($"There is more than one LevelGrid! {transform} - {Instance}");
            Destroy(gameObject);
            return;
        }

        Instance = this;

        gridSystem = new(10, 10, 2f);
        gridSystem.CreateDebugObjects(GridDebugObjectPrefab);
    }

    public void AddUnitAtGridPosition(GridPosition gridPosition, Unit unit) => gridSystem.GetGridObject(gridPosition).UnitList.Add(unit);

    public List<Unit> GetUnitListAtGridPosition(GridPosition gridPosition) => gridSystem.GetGridObject(gridPosition).UnitList;
    private void RemoveUnitAtGridPosition(GridPosition gridPosition, Unit unit) => gridSystem.GetGridObject(gridPosition).UnitList.Remove(unit);

    public GridPosition GetGridPosition(Vector3 worldPosition) => gridSystem.GetGridPosition(worldPosition);
    public Vector3 GetWorldPosition(GridPosition gridPosition) => gridSystem.GetWorldPosition(gridPosition);
    public bool IsValidGridPosition(GridPosition gridPosition) => gridSystem.IsValidGridPosition(gridPosition);

    public void UnitMovedGridPosition(Unit unit, GridPosition fromGridPosition, GridPosition toGridPosition) {
        RemoveUnitAtGridPosition(fromGridPosition, unit);
        AddUnitAtGridPosition(toGridPosition, unit);
    }

    public bool HasAnyUnitOnGridPosition(GridPosition gridPosition) => gridSystem.GetGridObject(gridPosition).UnitList.Count > 0;
}