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

namespace PerfectWorld.Scripts.Managers
{
    public class EC_InventoryUI : MonoBehaviour
    {
        [Header("Pack Buttons (assign in Inspector)")]
        [SerializeField] private List<Button> inventoryPackButtons = new List<Button>(); // byPackage: 0
        [SerializeField] private List<Button> equipmentPackButtons = new List<Button>(); // byPackage: 1
        [SerializeField] private List<Button> fashionPackButtons = new List<Button>();   // byPackage: 3

        [Header("Detail Panel (assign in Inspector)")]
        [SerializeField] private GameObject detailPanelRoot;
        [SerializeField] private bool hideDetailOnStart = true;
        [SerializeField] private TextOutlet nameText;
        [SerializeField] private TextOutlet templateIdText;
        [SerializeField] private TextOutlet countText;
        [SerializeField] private TextOutlet slotText;
        [SerializeField] private TextOutlet packageText;
        [SerializeField] private TextOutlet stateText;
        [SerializeField] private TextOutlet expireText;
        [SerializeField] private TextOutlet crcText;
        [SerializeField] private TextOutlet contentLenText;

        [Header("Inventory Settings")]
        [SerializeField] private bool autoRefresh = true;
        [SerializeField] private float refreshInterval = 1.0f;

        private float lastRefreshTime;

        private InventoryModel model;
        private InventoryView view;

        private const byte PKG_INVENTORY = 0;
        private const byte PKG_EQUIPMENT = 1;
        private const byte PKG_FASHION = 3; // Note: byPackage 3 used for Fashion

        private void Awake()
        {
            model = new InventoryModel();
            view = new InventoryView();
        }

        private void Start()
        {
            RefreshAll();
            if (hideDetailOnStart)
            {
                ShowDetailPanel(false);
            }
        }

        private void Update()
        {
            if (autoRefresh && Time.time - lastRefreshTime >= refreshInterval)
            {
                RefreshAll();
            }
        }

        public void RefreshAll()
        {
            lastRefreshTime = Time.time;

            var invItems = model.GetInventoryData(PKG_INVENTORY);
            var eqpItems = model.GetInventoryData(PKG_EQUIPMENT);
            var fshItems = model.GetInventoryData(PKG_FASHION);

            view.RenderPackage(inventoryPackButtons, invItems, PKG_INVENTORY, OnInventoryButtonClicked, GetDisplayTextForItem);
            view.RenderPackage(equipmentPackButtons, eqpItems, PKG_EQUIPMENT, OnInventoryButtonClicked, GetDisplayTextForItem);
            view.RenderPackage(fashionPackButtons, fshItems, PKG_FASHION, OnInventoryButtonClicked, GetDisplayTextForItem);
        }

        private void OnInventoryButtonClicked(byte package, int slot)
        {
            var data = model.GetInventoryData(package);
            if (data != null && data.TryGetValue(slot, out var itemData))
            {
                FillDetailPanel(package, itemData);
            }
            else
            {
                ShowDetailPanel(false);
            }
        }

        private string GetDisplayTextForItem(int slot, InventoryItemData itemData)
        {
            if (itemData == null || itemData.Count <= 0)
            {
                return string.Empty;
            }
            string itemName = EC_IvtrItem.ResolveItemName(itemData.TemplateId);
            string displayText = string.IsNullOrEmpty(itemName) ? $"Item {itemData.TemplateId}" : itemName;
            if (itemData.Count > 1)
            {
                displayText += $" x{itemData.Count}";
            }
            return displayText;
        }

        public void ToggleAutoRefresh()
        {
            autoRefresh = !autoRefresh;
        }

        public void SetRefreshInterval(float interval)
        {
            refreshInterval = Mathf.Max(0.1f, interval);
        }

        // === MVC: Model ===
        private class InventoryModel
        {
            private readonly FieldInfo itemsByPackageField;

            public InventoryModel()
            {
                var inventoryType = typeof(EC_Inventory);
                itemsByPackageField = inventoryType.GetField("_itemsByPackage", BindingFlags.NonPublic | BindingFlags.Static);
                if (itemsByPackageField == null)
                {
                    Debug.LogError("[InventoryUI] Could not access _itemsByPackage field from EC_Inventory");
                }
            }

            public Dictionary<int, InventoryItemData> GetInventoryData(byte package)
            {
                if (itemsByPackageField == null)
                {
                    return new Dictionary<int, InventoryItemData>();
                }
                var itemsByPackage = itemsByPackageField.GetValue(null) as Dictionary<byte, Dictionary<int, InventoryItemData>>;
                if (itemsByPackage == null)
                {
                    return new Dictionary<int, InventoryItemData>();
                }
                if (itemsByPackage.TryGetValue(package, out var packageItems))
                {
                    return packageItems;
                }
                return new Dictionary<int, InventoryItemData>();
            }
        }

        // === MVC: View ===
        private class InventoryView
        {
            public void RenderPackage(List<Button> buttons, Dictionary<int, InventoryItemData> items, byte package, System.Action<byte, int> onClick, System.Func<int, InventoryItemData, string> getDisplayText)
            {
                if (buttons == null)
                {
                    return;
                }

                for (int slot = 0; slot < buttons.Count; slot++)
                {
                    var button = buttons[slot];
                    if (button == null)
                    {
                        continue;
                    }

                    InventoryItemData itemData = null;
                    bool hasItem = items != null && items.TryGetValue(slot, out itemData);
                    button.onClick.RemoveAllListeners();
                    int capturedSlot = slot;
                    button.onClick.AddListener(() => onClick(package, capturedSlot));

                    // Optional visual tweaks based on state/count
                    var image = button.GetComponent<Image>();
                    if (image != null)
                    {
                        if (hasItem && itemData != null && itemData.State != 0)
                        {
                            image.color = Color.yellow;
                        }
                        else if (!hasItem)
                        {
                            image.color = Color.white;
                        }
                        else
                        {
                            image.color = Color.white;
                        }
                    }
                }
            }
        }

        // === Detail Panel Helpers ===
        [System.Serializable]
        private class TextOutlet
        {
            [SerializeField] public Text legacy;
            [SerializeField] public TMPro.TextMeshProUGUI tmp;

            public void Set(string value)
            {
                if (legacy != null)
                {
                    legacy.text = value ?? string.Empty;
                }
                if (tmp != null)
                {
                    tmp.text = value ?? string.Empty;
                }
            }
        }

        private void ShowDetailPanel(bool show)
        {
            if (detailPanelRoot != null)
            {
                detailPanelRoot.SetActive(show);
            }
        }

        private void FillDetailPanel(byte package, InventoryItemData item)
        {
            if (item == null)
            {
                ShowDetailPanel(false);
                return;
            }

            string name = EC_IvtrItem.ResolveItemName(item.TemplateId);
            nameText?.Set(string.IsNullOrEmpty(name) ? $"Item {item.TemplateId}" : name);
            templateIdText?.Set(item.TemplateId.ToString());
            countText?.Set(item.Count.ToString());
            slotText?.Set(item.Slot.ToString());
            packageText?.Set(GetPackageName(package));
            stateText?.Set(item.State.ToString());
            expireText?.Set(item.ExpireDate.ToString());
            crcText?.Set(item.Crc.ToString());
            contentLenText?.Set((item.Content?.Length ?? 0).ToString());

            ShowDetailPanel(true);
        }

        private static string GetPackageName(byte pkg)
        {
            switch (pkg)
            {
                case 0: return "PACK_INVENTORY";
                case 1: return "PACK_EQUIPMENT";
                case 3: return "PACK_FASHION";
                default: return $"PACK_{pkg}";
            }
        }
    }
}