using UnityEngine;
using UnityEngine.UI;
using System.Collections.Generic;
using TMPro;

public class ShopManager : MonoBehaviour
{
    [Header("Shop Settings")]
    public int startingMoney = 100;
    public Item[] availableItems; // Assumes Item is a MonoBehaviour attached to a Prefab

    [Header("UI Elements")]
    public TMP_Text moneyText;
    public Button[] buyButtons; 

    [Header("Inventory Settings")]
    public Transform storeRoomTransform; // Where physical items spawn
    public Transform inventoryUI; // The Panel with the Grid Layout Group
    public GameObject inventoryTextTemplate; // Drag a Prefab with TMP_Text here!

    private int currentMoney;
    private Dictionary<string, int> inventory = new Dictionary<string, int>();

    void Start()
    {
        currentMoney = startingMoney;

        // Initialize dictionary once at start
        PopulateInventoryDictionary();
        
        InitializeShopButtons();
        UpdateAllUI(); 
    }

    void InitializeShopButtons()
    {
        for (int i = 0; i < buyButtons.Length; i++)
        {
            if (i < availableItems.Length)
            {
                int index = i; 
                Item item = availableItems[index];
                Button button = buyButtons[index];

                // Set Button Text
                TMP_Text btnText = button.GetComponentInChildren<TMP_Text>();
                if (btnText != null) 
                {
                    btnText.text = $"{item.itemName} - ${item.itemPrice}";
                }

                // Add Click Listener
                button.onClick.RemoveAllListeners(); 
                button.onClick.AddListener(() => BuyItem(item, button));
            }
            else
            {
                buyButtons[i].gameObject.SetActive(false); 
            }
        }
    }

    void BuyItem(Item item, Button button)
    {
        if (currentMoney >= item.itemPrice)
        {
            // 1. Deduct Money
            currentMoney -= item.itemPrice;

            // 2. Instantiate physical item in the game world
            if(item.gameObject != null)
            {
                Instantiate(item.gameObject, storeRoomTransform.position, Quaternion.identity);
            }

            // 3. Logic: Add to dictionary
            if (!inventory.ContainsKey(item.itemName))
            {
                inventory[item.itemName] = 0;
            }   
            inventory[item.itemName]++;
            
            Debug.Log($"Purchased {item.itemName}");

            // 4. Update Button Feedback (Optional)
            TMP_Text btnText = button.GetComponentInChildren<TMP_Text>();
            if (btnText != null)
            {
                // Temporarily show "Bought" or keep price? 
                // Usually shops keep the price so you can buy again.
                // If you want it to flash green, you'd need a Coroutine, 
                // but for now let's keep it simple.
            }

            // 5. Refresh UI
            UpdateAllUI();
        }
        else
        {
            Debug.Log("Not enough money!");
        }
    }

    void UpdateAllUI()
    {
        // Update Money Text
        moneyText.text = "Money: $" + currentMoney;

        // Update Button Interactability
        for (int i = 0; i < buyButtons.Length; i++)
        {
            if (i < availableItems.Length)
            {
                buyButtons[i].interactable = (currentMoney >= availableItems[i].itemPrice);
            }
        }

        // Update Inventory List
        UpdateInventoryUI();
    }

    void PopulateInventoryDictionary()
    {
        foreach (Item item in availableItems)
        {
            if (!inventory.ContainsKey(item.itemName))
            {
                inventory[item.itemName] = 0;
            }
        }
    }

    void UpdateInventoryUI()
    {
        // 1. Clear existing list items
        foreach (Transform child in inventoryUI)
        {
            Destroy(child.gameObject);
        }

        // 2. Create new list items from the Template
        foreach (KeyValuePair<string, int> entry in inventory)
        {
            // Only show items we actually have (Count > 0)
            if(entry.Value > 0)
            {
                // Instantiate the Template (which has the TMP_Text component)
                GameObject newItem = Instantiate(inventoryTextTemplate, inventoryUI);
                
                // Get the text component and set the string
                TMP_Text textComp = newItem.GetComponent<TMP_Text>();
                if (textComp != null)
                {
                    textComp.text = $"{entry.Key}: {entry.Value}";
                }
            }
        }
    }
}