using System;
using System.Collections;
using System.Collections.Generic;
using System.Security.Permissions;
using UnityEditor;
using UnityEngine;
using UnityEngine.Assertions;
using UnityEngine.UI;

/// <summary>
/// This view is meant to be used in conjunction with a list. Realistically, it is mostly similar to the grid view,
/// as both operate with prototypes!
/// </summary>
public class ShopViewList : ShopView, IShopModelObserver<Item>
{
    private VerticalLayoutGroup _listLayoutGroup;    // This is essentially just a reference to ShopView's layout group but with the correct type

    [SerializeField] private ViewItemInfoPanel infoPanel;
    
    //protected ViewConfig viewConfig; //To set up the grid view, we need to know how many columns the grid view has, in the current setup,
    //this information can be found in a ViewConfig scriptable object, which serves as a configuration file for
    //views.
    
    // Start is called before the first frame update
    protected override void Awake()
    {
        //iewConfig = Resources.Load<ViewConfig>("ViewConfig");//Load the ViewConfig scriptable object from the Resources folder
        //Debug.Assert(viewConfig != null);
        Debug.Assert(_listLayoutGroup != null);
        Debug.Assert(infoPanel != null);
        base.Awake();
        model.RegisterObserver(this);
        print("ShopView Grid Initialised");
    }

    protected override void RegisterMoneyObserver()
    {
        var moneyComp = GetComponentInChildren<InventoryMoneyDisplay>();
        if (moneyComp != null) tradePartner.Inventory.RegisterObserver(moneyComp);
    }

    protected override void SetupItemIconView()
    {
        //_listLayoutGroup.constraint = GridLayoutGroup.Constraint.FixedColumnCount;//Set the constraint mode of the GridLayoutGroup
        //_listLayoutGroup.constraintCount = viewConfig.gridViewColumnCount; //Set the column count according to the ViewConfig object
        // Do we set up anything at all here?
    }

    protected override void ClearIconView()
    {
        Transform[] allIcons = layoutGroup.transform.GetComponentsInChildren<Transform>();
        foreach (Transform child in allIcons) {
            if (child != layoutGroup.transform) {
                Destroy(child.gameObject);
            }
        }
    }

    protected override void AddItemToView(Item item)
    {
        GameObject newItemIcon = GameObject.Instantiate(itemPrefab, layoutGroup.transform, true);
        newItemIcon.transform.localScale = Vector3.one;//The scale would automatically change in Unity so we set it back to Vector3.one.

        ViewItemContainer itemContainer = newItemIcon.GetComponent<ViewItemContainer>();
        Debug.Assert(itemContainer != null);
        //bool isSelected = (item == model.GetSelectedItem());
        var unsub = model.RegisterObserver(itemContainer);
        itemContainer.Initialize(item,model,unsub);
        shopController.AddSelectableItem(item);
        //print("Attempt to add item " + item.name + " to view");
    }

    protected override void RemoveItemFromView(Item item)
    {
        var items = layoutGroup.transform.GetComponentsInChildren<ViewItemContainer>();
        foreach (var itemView in items)
        {
            if (itemView.Item == item)
            {
                shopController.RemoveSelectableItem(item);
                model.RemoveObserver(itemView);
                Destroy(itemView.gameObject);
                return;
            }
        }
    }

    protected override void SwitchToKeyboardControl()
    {
        Destroy(shopController);//Remove the current controller component
        shopController = gameObject.AddComponent<ListKeyboardController>().Initialize(model);//Create and add a keyboard controller
        instructionText.text = "The current control mode is: Keyboard Control, WASD to select item, press K to buy. Press left mouse button to switch to Mouse Control.";
        buyButton.gameObject.SetActive(false);//Hide the buy button because we only use keyboard
    }

    protected override void SwitchToMouseControl()
    {
        Destroy(shopController);//Remove the current controller component
        shopController = gameObject.AddComponent<MouseController>().Initialize(model);//Create and add a mouse controller
        instructionText.text = "The current control mode is: Mouse Control, press 'K' to switch to Keyboard Control.";
        buyButton.gameObject.SetActive(true);//Show the buy button for the mouse controler
    }

    private void OnValidate()
    {
        _listLayoutGroup = (VerticalLayoutGroup) layoutGroup;
        bool correctLayout = _listLayoutGroup != null;
        if(!correctLayout) Debug.LogError("Layout group is not of type Vertical!",this);
        //else Debug.Log("Grid shop view validated",this);
    }


    public void OnSelected(Item item)
    {
        if(item != null) infoPanel.gameObject.SetActive(true);
        infoPanel?.SetItemInfo(item,model);   // ? works here as it's meant to live through the whole lifetime of this gameobject anyway
    }

    public void OnRemoved(Item item)
    {
        infoPanel?.SetItemInfo(null);   // This should set the item info to nothing, effectively disabling it
        shopController.RemoveSelectableItem(item);
    }

    public void OnAdded(Item item)
    {
        throw new NotImplementedException();
    }

    public void OnTransaction(int moneyDelta)
    {
        
    }
}