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

namespace Ichni.Menu.UI
{
    /// <summary>
    /// 通用 SelectionBox 的页面宿主，职责等同于 MessageBox 的页面容器：
    /// 显示时动态生成一个 SelectionBox，选择完成后统一淡出并销毁本次实例。
    /// </summary>
    public class SelectionBoxUIPage : UIPageBase
    {
        [Header("Selection Box Page")]
        public SelectionBox selectionBoxPrefab;
        public RectTransform selectionBoxContainer;

        private SelectionBox _currentSelectionBox;
        private bool _isShowing;

        /// <summary>当前是否已有一个 SelectionBox 等待玩家选择。</summary>
        public bool IsShowing => _isShowing;

        /// <summary>
        /// 生成并显示一组运行时选项。页面显示期间拒绝重复请求，避免两个弹窗争夺输入。
        /// </summary>
        public bool Show(string title, string content, IReadOnlyList<SelectionBoxOption> options)
        {
            if (_isShowing)
            {
                Debug.LogWarning("[SelectionBoxUIPage] 已有 SelectionBox 显示中，忽略重复请求。");
                return false;
            }

            if (mainCanvasGroup == null || selectionBoxPrefab == null || selectionBoxContainer == null)
            {
                Debug.LogWarning("[SelectionBoxUIPage] 缺少 CanvasGroup、SelectionBox Prefab 或容器，无法显示选项框。");
                return false;
            }

            _currentSelectionBox = Instantiate(selectionBoxPrefab, selectionBoxContainer);
            _currentSelectionBox.Closed += HandleSelectionBoxClosed;
            if (!_currentSelectionBox.SetUp(title, content, options))
            {
                Destroy(_currentSelectionBox.gameObject);
                _currentSelectionBox = null;
                return false;
            }

            _isShowing = true;

            // UIPageBase 默认淡入完成后才开启射线；选择框从出现瞬间就必须阻断底层输入。
            mainCanvasGroup.gameObject.SetActive(true);
            mainCanvasGroup.interactable = true;
            mainCanvasGroup.blocksRaycasts = true;
            FadeIn();
            return true;
        }

        private void HandleSelectionBoxClosed(SelectionBox selectionBox)
        {
            if (selectionBox != _currentSelectionBox) return;

            FadeOut(0.2f, false, () =>
            {
                if (_currentSelectionBox != null)
                    Destroy(_currentSelectionBox.gameObject);

                _currentSelectionBox = null;
                _isShowing = false;
            });
        }
    }
}