Untitled

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using DG.Tweening;
using TMPro;

public class Inventory : MonoBehaviour
{
    [HideInInspector] public int heldItemIndex = 0;

    public GameObject equippedObject;
    public Item selectedObject;
    public Item emptyObjectTemplate;

    [Header("Inventory Values")]
    [HideInInspector] public List<Item> inventoryItems = new List<Item>();
    [HideInInspector] public List<GameObject> inventoryObjects = new List<GameObject>();
    public List<GameObject> slotList = new List<GameObject>();
    public bool inventoryFull = false;

    [Header("UI Values")]
    public TextMeshProUGUI itemName;
    public TextMeshProUGUI itemDescription;
    public float spinSpeed;
    public Transform spinOrigin;

    private bool canSpin = true;

    private void Start()
    {
        Initialise();
    }

    private void Initialise()
    {
        heldItemIndex = 0;
    }

    private void Update()
    {
        if (equippedObject != null && inventoryObjects.Count > 0)
        {
            if (equippedObject.activeSelf == false)
                equippedObject.SetActive(true);

            foreach (GameObject _object in inventoryObjects)
            {
                if (_object != equippedObject)
                    _object.SetActive(false);
            }
        }
        else if (selectedObject == emptyObjectTemplate)
        {
            equippedObject = null;
        }

        if (inventoryObjects.Count > 0)
            selectedObject = inventoryItems[heldItemIndex];
        else if (inventoryObjects.Count == 0)
            selectedObject = emptyObjectTemplate;

        itemName.text = selectedObject.displayName;
        itemDescription.text = selectedObject.description;

        if (inventoryObjects.Count == 4)
            inventoryFull = true;
        else
            inventoryFull = false;

        _Input();
    }

    public void AddItem(Item newItem, GameObject newObject)
    {
        equippedObject = newObject;
        inventoryItems.Add(newItem);
        inventoryObjects.Add(newObject);

        for (int i = 0; i < slotList.Count; i++)
        {
            if (slotList[i].transform.childCount == 0)
            {
                Instantiate(newItem.inventoryPrefab, slotList[i].transform.position, transform.rotation, slotList[i].transform);
                break;
            }
        }
    }

    public void RemoveItem(Item item, GameObject _object)
    {
        if (inventoryItems.Contains(item) && inventoryObjects.Contains(_object))
        {
            for (int i = 0; i < slotList.Count; i++)
            {
                if (slotList[i].transform.childCount > 0)
                {
                    Destroy(slotList[i].transform.GetChild(0).gameObject);
                    break;
                }
            }

            int nextIndex = (heldItemIndex + 1) % inventoryItems.Count;
            if (inventoryItems[nextIndex] != emptyObjectTemplate)
            {
                if (nextIndex < 4 && nextIndex > -1)
                {
                    heldItemIndex = (heldItemIndex + 1) % inventoryItems.Count;
                    equippedObject = inventoryObjects[heldItemIndex];
                    Spin(90f, false);
                }
            }

            inventoryItems.Remove(item);
            inventoryObjects.Remove(_object);

            if (inventoryObjects.Count > 0)
            {
                heldItemIndex = Mathf.Clamp(heldItemIndex, 0, inventoryObjects.Count - 1);
                equippedObject = inventoryObjects[heldItemIndex];
                equippedObject.SetActive(true);
            }
            else
            {
                equippedObject = null;
            }
        }
    }

    private void _Input()
    {
        var inventoryUI = GetComponentInChildren<InventoryUI>();
        if (inventoryUI.isOpen == true && canSpin)
        {
            if (inventoryObjects.Count > 1)
            {
                if (Input.GetKeyDown(KeyCode.DownArrow))
                {
                    if (inventoryFull)
                    {
                        int nextIndex = (heldItemIndex - 1 + inventoryItems.Count) % inventoryItems.Count;
                        if (inventoryItems[nextIndex] != emptyObjectTemplate)
                        {
                            if (nextIndex < 4 && nextIndex > -1)
                            {
                                heldItemIndex = (heldItemIndex - 1 + inventoryItems.Count) % inventoryItems.Count;
                                equippedObject = inventoryObjects[heldItemIndex];
                                Spin(-90f, true);
                            }
                        }
                    }
                    else if (heldItemIndex > 0 && !inventoryFull)
                    {
                        int nextIndex = (heldItemIndex - 1 + inventoryItems.Count) % inventoryItems.Count;
                        if (inventoryItems[nextIndex] != emptyObjectTemplate)
                        {
                            if (nextIndex < 4 && nextIndex > -1)
                            {
                                heldItemIndex = (heldItemIndex - 1 + inventoryItems.Count) % inventoryItems.Count;
                                equippedObject = inventoryObjects[heldItemIndex];
                                Spin(-90f, true);
                            }
                        }
                    }
                }

                if (Input.GetKeyDown(KeyCode.UpArrow))
                {
                    if (inventoryFull)
                    {
                        int nextIndex = (heldItemIndex + 1) % inventoryItems.Count;
                        if (inventoryItems[nextIndex] != emptyObjectTemplate)
                        {
                            if (nextIndex < 4 && nextIndex > -1)
                            {
                                heldItemIndex = (heldItemIndex + 1) % inventoryItems.Count;
                                equippedObject = inventoryObjects[heldItemIndex];
                                Spin(90f, true);
                            }
                        }
                    }
                    else if (heldItemIndex < inventoryItems.Count - 1 && !inventoryFull)
                    {
                        int nextIndex = (heldItemIndex + 1) % inventoryItems.Count;
                        if (inventoryItems[nextIndex] != emptyObjectTemplate)
                        {
                            if (nextIndex < 4 && nextIndex > -1)
                            {
                                heldItemIndex = (heldItemIndex + 1) % inventoryItems.Count;
                                equippedObject = inventoryObjects[heldItemIndex];
                                Spin(90f, true);
                            }
                        }
                    }
                }
            }
        }
    }

    public void Spin(float direction, bool withSound)
    {
        GetComponentInChildren<InventoryUI>().SwitchSound();

        canSpin = false;
        spinOrigin.DORotate(new Vector3(direction, 0, 0), spinSpeed, RotateMode.LocalAxisAdd).SetEase(Ease.OutCubic).OnComplete(() => SpinDone());
    }

    private void SpinDone()
    {
        canSpin = true;
    }
}