using System.Collections.Generic;
using Cielonos.Core.Interaction;
using DG.Tweening;
using Sirenix.OdinInspector;
using SLSUtilities.UI;
using UnityEngine;

namespace Cielonos.UI
{
    /// <summary>
    /// 交互选项列表 UI 页面。
    /// 玩家进入可交互物体范围时由 PlayerInteractionSubcontroller 调用 Show()，离开时调用 Hide()。
    /// 当选项数量为 1 时，直接显示单个选项而不需要导航；
    /// 当选项数量大于 1 时，玩家可用鼠标滚轮或上/下键切换高亮选项，R 键执行。
    /// </summary>
    public class InteractionUIArea : UIElementBase
    {
        [Title("容器")]
        [Tooltip("单个选项条目的预制体，需包含 InteractionChoiceItem 组件。")]
        [SerializeField] private GameObject choiceItemPrefab;

        [Tooltip("选项条目的父节点（Layout Group）。")]
        [SerializeField] private RectTransform choiceContainer;

        private readonly List<InteractionChoiceItem> _items = new List<InteractionChoiceItem>();

        private void Start()
        {
            Hide();
        }

        // ====================================================================
        // 对外接口
        // ====================================================================

        /// <summary>
        /// 显示选项列表并高亮指定索引的选项。
        /// 由 PlayerInteractionSubcontroller.SetCurrentInteractable() 调用。
        /// </summary>
        public void Show(List<InteractionChoice> choices, int selectedIndex)
        {
            gameObject.SetActive(true);
            canvasGroup.DOFade(1f, 0.25f).From(0).OnComplete(() =>
            {
                canvasGroup.interactable = true;
                canvasGroup.blocksRaycasts = true;
            }).Play();
            rectTransform.DOLocalMoveY(-50f, 0.25f).From(-250f).Play();
            ClearItems();

            if (choices == null || choices.Count == 0)
            {
                gameObject.SetActive(false);
                return;
            }

            foreach (InteractionChoice choice in choices)
            {
                InteractionChoiceItem item = CreateItem();
                if (item != null)
                {
                    item.Setup(choice.choiceName, choice.isInteractable);
                }
            }

            UpdateHighlight(selectedIndex);
        }

        /// <summary>
        /// 更新高亮选项。由 PlayerInteractionSubcontroller.NavigateChoice() 调用。
        /// </summary>
        public void UpdateHighlight(int selectedIndex)
        {
            for (int i = 0; i < _items.Count; i++)
            {
                _items[i].SetHighlighted(i == selectedIndex);
            }
        }

        /// <summary>
        /// 隐藏选项列表。由 PlayerInteractionSubcontroller.RemoveCurrentInteractable() 调用。
        /// </summary>
        public override void Hide()
        {
            canvasGroup.interactable = false;
            canvasGroup.blocksRaycasts = false;
            canvasGroup.DOFade(0f, 0.25f).OnComplete(() =>
            {
                ClearItems(); 
                gameObject.SetActive(false);
            }).Play();
            rectTransform.DOLocalMoveY(-250f, 0.25f).Play();
        }

        // ====================================================================
        // 内部工具
        // ====================================================================

        private InteractionChoiceItem CreateItem()
        {
            if (choiceItemPrefab == null || choiceContainer == null)
            {
                Debug.LogError("[InteractionUIPage] choiceItemPrefab 或 choiceContainer 未在 Inspector 中配置。");
                return null;
            }

            GameObject go = Instantiate(choiceItemPrefab, choiceContainer);
            InteractionChoiceItem item = go.GetComponent<InteractionChoiceItem>();

            if (item == null)
            {
                Debug.LogError("[InteractionUIPage] choiceItemPrefab 缺少 InteractionChoiceItem 组件。");
                Destroy(go);
                return null;
            }

            _items.Add(item);
            return item;
        }

        private void ClearItems()
        {
            foreach (InteractionChoiceItem item in _items)
            {
                if (item != null) Destroy(item.gameObject);
            }
            _items.Clear();
        }
    }
}