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

[Serializable]
public class Inventory : MonoBehaviour
{
    public List<InventorySlot> additionalSlots;

    public GameObject itemContainerPrefab;

    private List<InventorySlot> _inventorySlots;

    private void Awake()
    {
        _inventorySlots = new List<InventorySlot>();
        foreach (var inventorySlot in additionalSlots)
        {
            inventorySlot.SetParentInventory(this);
            _inventorySlots.Add(inventorySlot);
        }
    }

    private void OnEnable()
    {
        var inventorySlotsInChildren = GetComponentsInChildren<InventorySlot>();
        foreach (var inventorySlot in inventorySlotsInChildren)
        {
            inventorySlot.SetParentInventory(this);
            _inventorySlots.Add(inventorySlot);
        }
    }

    public bool AddItem(ItemData item)
    {
        if (item.canStack)
        {
            return AddItem(ConvertToInventoryItem(item));
        }
        
        return AddToFirstOpenSlot(item.gameObject);
    }

    public bool AddItem(InventoryItem item)
    {
        //Stacks the item if it already exists in the inventory.
        foreach (var inventorySlot in _inventorySlots.Where(inventorySlot =>
                     inventorySlot.ContainsItem(item.GetItemid())))
        {
            inventorySlot.GetItem().ChangeCount(item.Count);
            return true;
        }

        return AddToFirstOpenSlot(item.gameObject);
        
    }

    private bool AddToFirstOpenSlot(GameObject item)
    {

        foreach (var inventorySlot in _inventorySlots.Where(inventorySlot => !inventorySlot.ContainsItem()))
        {
            inventorySlot.AssignItem(item);
            return true;
        }
        return false;
    }

    private InventoryItem ConvertToInventoryItem(ItemData item)
    {
        var inventoryItem = Instantiate(itemContainerPrefab, transform);
        itemContainerPrefab.GetComponent<InventoryItem>().itemPrefab = item.gameObject;

        return inventoryItem.gameObject.GetComponent<InventoryItem>();
    }
}