using UnityEngine;
using Ashwild.Player;

namespace Ashwild.Inventory
{
    public class HotbarController : MonoBehaviour
    {
        [Header("References")]
        [SerializeField] private Transform toolHolder;
        [SerializeField] private PlayerToolHolder toolHolderAnim;
        [SerializeField] private Transform raycastOrigin;

        private PlayerInventory inventory;
        private GameObject currentHeldObject;
        private ItemData currentHeldItem;
        private bool isSwitching;
        private HeldItemContext heldContext;

        private void Start()
        {
            inventory = PlayerInventory.Instance;
            inventory.onSelectedSlotChanged.AddListener(OnSelectionChanged);
            inventory.onSlotChanged.AddListener(OnSlotChanged);
            heldContext = new HeldItemContext { RaycastOrigin = raycastOrigin };
            UpdateHeldItem(false);
        }

        private void OnDestroy()
        {
            if (inventory != null)
            {
                inventory.onSelectedSlotChanged.RemoveListener(OnSelectionChanged);
                inventory.onSlotChanged.RemoveListener(OnSlotChanged);
            }
        }

        private void OnSelectionChanged(int index)
        {
            UpdateHeldItem(true);
        }

        private void OnSlotChanged(int index)
        {
            if (index == inventory.SelectedHotbarIndex)
                UpdateHeldItem(true);
        }

        private void UpdateHeldItem(bool animate)
        {
            InventorySlot selected = inventory.GetSelectedSlot();
            ItemData newItem = selected.IsEmpty ? null : selected.ItemData;

            if (newItem == currentHeldItem)
                return;

            if (isSwitching)
            {
                if (currentHeldObject != null)
                {
                    Destroy(currentHeldObject);
                    currentHeldObject = null;
                }
                isSwitching = false;
            }

            if (animate && currentHeldObject != null && toolHolderAnim != null)
            {
                isSwitching = true;
                toolHolderAnim.PlayUnequipAnimation(() =>
                {
                    if (currentHeldObject != null)
                    {
                        Destroy(currentHeldObject);
                        currentHeldObject = null;
                    }
                    currentHeldItem = newItem;
                    SpawnItem(newItem);
                    isSwitching = false;

                    if (currentHeldObject != null)
                        toolHolderAnim.PlayEquipAnimation();
                });
            }
            else
            {
                if (currentHeldObject != null)
                {
                    Destroy(currentHeldObject);
                    currentHeldObject = null;
                }
                currentHeldItem = newItem;
                SpawnItem(newItem);

                if (animate && toolHolderAnim != null && currentHeldObject != null)
                    toolHolderAnim.PlayEquipAnimation();
            }
        }

        private void SpawnItem(ItemData item)
        {
            if (item == null || item.HandPrefab == null || toolHolder == null)
                return;

            currentHeldObject = Instantiate(item.HandPrefab, toolHolder);

            // Link the freshly spawned held item to the player so its behaviour
            // (tool, consumable, ...) can interact — only the equipped item is alive.
            IHeldItemBehaviour behaviour = currentHeldObject.GetComponentInChildren<IHeldItemBehaviour>(true);
            if (behaviour != null)
                behaviour.Setup(heldContext, item);
        }
    }
}