using UnityEngine;

public class Inventory : MonoBehaviour
{
    [SerializeField]
    private int width = 10;

    [SerializeField]
    private int height = 6;

    public int Width => width;
    public int Height => height;

    private InventoryItemPlacement[,] grid;


    [SerializeField]
    private InventoryItem testInventoryItem;
    private void Start()
    {
        PlaceItem(testInventoryItem, 0, 0);
    }


    private void Awake()
    {
        grid = new InventoryItemPlacement[width, height];
    }

    public bool CanPlaceItem(InventoryItem item, int startX, int startY)
    {
        for (int x = 0; x < item.gridX; x++)
        {
            for (int y = 0; y < item.gridY; y++)
            {
                if (!item.IsOccupied(x, y))
                    continue;

                int inventoryX = startX + x;
                int inventoryY = startY + y;

                // Outside inventory?
                if (inventoryX < 0 ||
                    inventoryX >= width ||
                    inventoryY < 0 ||
                    inventoryY >= height)
                {
                    return false;
                }

                // Something already here?
                if (grid[inventoryX, inventoryY] != null)
                {
                    return false;
                }
            }
        }

        return true;
    }

    public bool PlaceItem(InventoryItem item, int startX, int startY)
    {
        if (!CanPlaceItem(item, startX, startY)) 
        {
            return false;
        }

        InventoryItemPlacement placement = new InventoryItemPlacement(item, new Vector2Int(startX, startY));

        for (int x = 0; x < item.gridX; x++)
        {
            for (int y = 0; y < item.gridY; y++)
            {
                if (!item.IsOccupied(x, y))
                {
                    continue;
                }

                grid[startX + x, startY + y] = placement;
            }
        }

        return true;
    }

    public void RemoveItem(InventoryItem item)
    {
        for (int x = 0; x < width; x++)
        {
            for (int y = 0; y < height; y++)
            {
                if (grid[x, y] != null && grid[x, y].Item == item)
                {
                    grid[x, y] = null;
                }
            }
        }
    }

    public InventoryItemPlacement GetPlacementAt(int x, int y)
    {
        if (x < 0 || x >= width || y < 0 || y >= height)
        {
            return null;
        }

        return grid[x, y];
    }

    public InventoryItem GetItemAt(int x, int y)
    {
        InventoryItemPlacement placement = GetPlacementAt(x, y);

        if (placement == null)
            return null;

        return placement.Item;
    }
}