using UnityEngine;
using System.Collections;
using UnityEngine.EventSystems;
using UnityEngine.UI;




public class InventoryUIController : UiController {

    public Inventory inventory;
    public ItemsView itemsView;
    public UnityEngine.UI.Image selectionImage;
    public UnityEngine.UI.Text selectionText;
    public UnityEngine.UI.Button removeButton;
    public UnityEngine.UI.Button equipButton;
    private ItemViewController _selectedItem;

    public void Rebuild() {
        itemsView.Items = inventory.Items;
        ResetFocus();

    }

    public void ResetFocus() {
        var es = EventSystemManager.currentSystem;
        if (itemsView.Views.Count > 0) {
            es.SetSelectedGameObject(itemsView.Views[0].itemButton.gameObject, new BaseEventData(es));
        }
        
    }

	// Use this for initialization
	void Start () {
	    if (itemsView == null) {
	        Debug.LogWarning("Items view not set up! Inventory UI would not function properly!");
	    }
	    else {
            itemsView.SelectionChanged += itemsView_SelectionChanged;
	    }

	    if (equipButton != null) {
	        equipButton.onClick.AddListener(OnEquipClick);
	    }
	    else {
	        Debug.LogWarning("Equip button not assigned!");
	    }

    
	}

    void OnEquipClick(UnityEngine.UI.Button button) {
        EquippedChange();
    }

    void EquippedChange() {
        var item = itemsView.Selection.item;
        if (item != null && item.description.IsEquippable) {
            if (item.equipped) {
                inventory.UnequipItem(item);
            } else {
                inventory.EquipItem(item);
            }
        }
    }

    void itemsView_SelectionChanged(ItemsView container) {
        if (_selectedItem == container.Selection) {
            EquippedChange();
        }
        else {
            _selectedItem = container.Selection;
            selectionImage.sprite = container.Selection.item.inventoryIcon;
            selectionText.text = container.Selection.item.description.Description;
        }
      

        UpdateButtons();
    }

    private void UpdateButtons() {
        if (itemsView == null || itemsView.Selection == null || itemsView.Selection.item == null) {
            if (equipButton != null) {
                equipButton.gameObject.SetActive(false);
            }
            if (removeButton != null) {
                removeButton.gameObject.SetActive(false);
            }
        }
        else {
            var item = itemsView.Selection.item;

            //update equip button
            if (!item.description.IsEquippable) {
                equipButton.gameObject.SetActive(false);
            }
            else {
                equipButton.gameObject.SetActive(true);
                if (item.equipped) {
                    equipButton.GetComponentInChildren<Text>().text = "Unequip";
                }
                else {
                    equipButton.GetComponentInChildren<Text>().text = "Equip";
                }
            }
                
        }
      
    }
	
	// Update is called once per frame
	void Update () {
	
	}
}