using System;
using System.Collections.Generic;
using Cielonos.MainGame.Inventory;
using Cielonos.MainGame.Inventory.Collections;
using Sirenix.OdinInspector;
using SLSUtilities.UI;
using UnityEngine;
using UnityEngine.UI;

namespace Cielonos.MainGame.UI
{
    /// <summary>
    /// 战后奖励选择界面的 UI 页面控制器。
    /// 弹出时显示 3 个奖励卡片，玩家选择某一个卡片后，可以在详情面板中查看物品描述（或装备升级预览属性增益）。
    /// 点击确认后，将奖励分发给玩家并关闭界面。
    /// </summary>
    public class RewardChoiceUIPage : UIPageBase
    {
        [Title("Selectors")]
        [Tooltip("单个奖励选择卡片的预制体。")]
        public GameObject selectorPrefab;
        [Tooltip("卡片实例的父容器。")]
        public RectTransform selectorContainer;
        [Tooltip("当前生成的卡片列表。")]
        public List<RewardChoiceSelector> selectors = new List<RewardChoiceSelector>();

        [Title("Detail Panel")]
        [Tooltip("右侧物品详细信息展示面板。")]
        public ItemDetailPanel itemDetailPanel;

        [Title("Buttons")]
        [Tooltip("确认选择的按钮。")]
        public Button confirmButton;
        [Tooltip("关闭/放弃选择的按钮。")]
        public Button closeButton;

        private RewardChoiceSelector currentSelected;
        private Action<int> onConfirmCallback;

        /// <summary>当前被选中的选项索引，若无选中则返回 -1。</summary>
        public int SelectedIndex => currentSelected != null ? selectors.IndexOf(currentSelected) : -1;

        protected override void Start()
        {
            base.Start();

            if (confirmButton != null)
            {
                confirmButton.onClick.AddListener(OnConfirmClicked);
            }

            if (closeButton != null)
            {
                closeButton.onClick.AddListener(OnCloseClicked);
            }
        }

        /// <summary>
        /// 设置候选奖励物品池并初始化卡片列表。
        /// </summary>
        /// <param name="offers">生成的候选物品实例列表。</param>
        /// <param name="onConfirm">当玩家确认选择时的回调函数（传入被选中的物品索引）。</param>
        public void SetOffers(List<ItemBase> offers, Action<int> onConfirm)
        {
            onConfirmCallback = onConfirm;
            ClearSelectors();

            if (offers == null) return;

            // 循环为候选池中的每个物品生成卡片 UI
            for (int i = 0; i < offers.Count; i++)
            {
                ItemBase item = offers[i];
                if (item == null) continue;

                RewardChoiceSelector selector = CreateSelector();
                selector.Setup(item);
            }

            currentSelected = null;
            RefreshConfirmButton();

            if (itemDetailPanel != null)
            {
                itemDetailPanel.ClearPanel();
            }
        }

        /// <summary>
        /// 被卡片回调调用，当玩家点击某张卡片时更新选中状态，并在右侧面板展示详情。
        /// </summary>
        public void SelectItem(RewardChoiceSelector selector)
        {
            if (selector == null || !selectors.Contains(selector)) return;

            // 取消之前选中卡片的高亮
            if (currentSelected != null)
            {
                currentSelected.SetSelected(false);
            }

            // 设当前点击的卡片为选中状态
            currentSelected = selector;
            currentSelected.SetSelected(true);

            if (itemDetailPanel != null)
            {
                ItemBase displayItem = currentSelected.item;
                
                // 针对升级组件（PrefabricatedComponent）做特殊处理：在详情页展示其目标装备升级前后的属性对比
                if (displayItem is PrefabricatedComponent prefabComp && prefabComp.targetEquipment != null)
                {
                    displayItem = prefabComp.targetEquipment;
                    itemDetailPanel.SetItem(displayItem);

                    // 在普通面板下方追加展示“属性提升预览”
                    int currentLvl = displayItem.passiveAttributeSm?.level ?? 0;
                    itemDetailPanel.AppendUpgradePreview(displayItem.upgradeData, currentLvl, prefabComp.stackAmount);
                }
                else
                {
                    // 普通道具直接显示基础描述
                    itemDetailPanel.SetItem(displayItem);
                }
            }

            RefreshConfirmButton();
        }

        protected override void OnPageOpened()
        {
            RefreshConfirmButton();
        }

        protected override void OnPageClosed()
        {
            currentSelected = null;
            onConfirmCallback = null;
        }

        /// <summary>确认选择按钮点击事件，执行回调并关闭页面。</summary>
        private void OnConfirmClicked()
        {
            if (currentSelected == null) return;

            int index = SelectedIndex;
            if (index < 0) return;

            Action<int> callback = onConfirmCallback;
            Close();
            callback?.Invoke(index);
        }

        /// <summary>关闭按钮点击事件，关闭当前界面。</summary>
        private void OnCloseClicked()
        {
            Close();
        }

        /// <summary>从预制体实例化一个新的奖励卡片 UI。</summary>
        private RewardChoiceSelector CreateSelector()
        {
            if (selectorPrefab == null || selectorContainer == null)
            {
                Debug.LogError("[RewardChoiceUIPage] selectorPrefab 或 selectorContainer 未配置。");
                return null;
            }

            GameObject obj = Instantiate(selectorPrefab, selectorContainer);
            RewardChoiceSelector selector = obj.GetComponent<RewardChoiceSelector>();
            if (selector == null)
            {
                Debug.LogError("[RewardChoiceUIPage] selectorPrefab 缺少 RewardChoiceSelector 组件。");
                Destroy(obj);
                return null;
            }

            selectors.Add(selector);
            return selector;
        }

        /// <summary>清空所有已生成的卡片实例。</summary>
        private void ClearSelectors()
        {
            foreach (RewardChoiceSelector selector in selectors)
            {
                if (selector != null)
                {
                    Destroy(selector.gameObject);
                }
            }

            selectors.Clear();
            currentSelected = null;
        }

        /// <summary>刷新确认按钮的启用/禁用状态（仅在选中卡片后可用）。</summary>
        private void RefreshConfirmButton()
        {
            if (confirmButton != null)
            {
                confirmButton.interactable = currentSelected != null;
            }
        }
    }
}