using System.Collections.Generic;
using UnityEngine;

public class ItemPanelPool : MonoBehaviour
{
    [Header("Pool Settings")]
    public GameObject itemPanelPrefab;
    public int initialPoolSize = 20;
    public int maxPoolSize = 100;
    public bool expandPool = true;
    
    [Header("Pool Management")]
    public Transform poolParent; // Where inactive objects are stored
    
    private Queue<GameObject> availablePanels = new Queue<GameObject>();
    private List<GameObject> allPanels = new List<GameObject>();
    private int currentPoolSize = 0;
    
    void Start()
    {
        InitializePool();
    }
    
    void InitializePool()
    {
        if (itemPanelPrefab == null)
        {
            Debug.LogError("ItemPanelPrefab is not assigned!");
            return;
        }
        
        // Create pool parent if not assigned
        if (poolParent == null)
        {
            GameObject poolParentObj = new GameObject("ItemPanelPool");
            poolParentObj.transform.SetParent(transform);
            poolParent = poolParentObj.transform;
        }
        
        // Pre-populate pool
        for (int i = 0; i < initialPoolSize; i++)
        {
            CreateNewPanel();
        }
        
        Debug.Log($"ItemPanelPool initialized with {currentPoolSize} panels");
    }
    
    GameObject CreateNewPanel()
    {
        if (itemPanelPrefab == null) return null;
        
        GameObject newPanel = Instantiate(itemPanelPrefab, poolParent);
        newPanel.SetActive(false);
        
        // Add ShopItemPanel component if not present
        ShopItemPanel panelScript = newPanel.GetComponent<ShopItemPanel>();
        if (panelScript == null)
        {
            panelScript = newPanel.AddComponent<ShopItemPanel>();
        }
        
        availablePanels.Enqueue(newPanel);
        allPanels.Add(newPanel);
        currentPoolSize++;
        
        return newPanel;
    }
    
    public GameObject GetPanel()
    {
        GameObject panel = null;
        
        // Try to get from available pool
        if (availablePanels.Count > 0)
        {
            panel = availablePanels.Dequeue();
        }
        // Create new panel if pool is empty and we can expand
        else if (expandPool && currentPoolSize < maxPoolSize)
        {
            panel = CreateNewPanel();
            if (panel != null)
            {
                panel = availablePanels.Dequeue(); // Get the panel we just created
            }
        }
        // Pool is full and can't expand
        else
        {
            Debug.LogWarning("ItemPanelPool is full and cannot expand further!");
            return null;
        }
        
        if (panel != null)
        {
            panel.SetActive(true);
            
            // Reset the panel state
            ShopItemPanel panelScript = panel.GetComponent<ShopItemPanel>();
            if (panelScript != null)
            {
                panelScript.ResetPanel(); // Reset for reuse
            }
        }
        
        return panel;
    }
    
    public void ReturnPanel(GameObject panel)
    {
        if (panel == null) return;
        
        // Reset panel state
        ShopItemPanel panelScript = panel.GetComponent<ShopItemPanel>();
        if (panelScript != null)
        {
            panelScript.ResetPanel(); // Reset for reuse
        }
        
        // Deactivate and move to pool parent
        panel.SetActive(false);
        panel.transform.SetParent(poolParent);
        panel.transform.localPosition = Vector3.zero;
        panel.transform.localRotation = Quaternion.identity;
        panel.transform.localScale = Vector3.one;
        
        // Add back to available pool
        availablePanels.Enqueue(panel);
    }
    
    public void ReturnAllPanels()
    {
        // Return all active panels to pool
        foreach (GameObject panel in allPanels)
        {
            if (panel != null && panel.activeInHierarchy)
            {
                ReturnPanel(panel);
            }
        }
    }
    
    public int GetAvailableCount()
    {
        return availablePanels.Count;
    }
    
    public int GetActiveCount()
    {
        int activeCount = 0;
        foreach (GameObject panel in allPanels)
        {
            if (panel != null && panel.activeInHierarchy)
            {
                activeCount++;
            }
        }
        return activeCount;
    }
    
    public int GetTotalCount()
    {
        return currentPoolSize;
    }
    
    public void ClearPool()
    {
        // Destroy all panels
        foreach (GameObject panel in allPanels)
        {
            if (panel != null)
            {
                DestroyImmediate(panel);
            }
        }
        
        availablePanels.Clear();
        allPanels.Clear();
        currentPoolSize = 0;
    }
    
    void OnDestroy()
    {
        ClearPool();
    }
    
    [ContextMenu("Log Pool Status")]
    void LogPoolStatus()
    {
        Debug.Log($"Pool Status - Available: {GetAvailableCount()}, Active: {GetActiveCount()}, Total: {GetTotalCount()}");
    }
}