using System.Collections;
using System.Collections.Generic;
using AK.Wwise;
using Ichni.Menu;
using UnityEngine;
using UnityEngine.Serialization;

namespace Ichni
{
    /// <summary>
    /// GameScene 返回 MenuScene 后应恢复的页面。
    /// 该枚举替代互斥的布尔标记，避免普通歌曲与教程返回状态同时残留。
    /// </summary>
    public enum MenuReturnDestination
    {
        None,
        SongSelection,
        Story
    }

    public class InformationTransistor : MonoBehaviour
    {
        public static InformationTransistor instance;

        /// <summary>
        /// 当前游戏运行结束后，MenuScene 应恢复的唯一目标页面。
        /// 运行期间保存在 DontDestroyOnLoad 对象中，不写入玩家存档。
        /// </summary>
        public MenuReturnDestination menuReturnDestination;

        public ChapterSelectionUnit chapter;
        public SongItemData song;
        public DifficultyData difficulty;

        public float songLength;
        public float bpm;
    
        public Switch chapterSwitch;
        public Switch songSwitch;
        
        private void Awake()
        {
            if (instance == null)
            {
                instance = this;
                DontDestroyOnLoad(gameObject);
                menuReturnDestination = MenuReturnDestination.None;
            }
            else
            {
                Destroy(gameObject);
            }
        }
        
        public void SetInformation(ChapterSelectionUnit chapter,
            SongItemData song, DifficultyData difficulty)
        {
            // 保留旧入口，供现有选曲流程在播放过场前预先写入歌曲信息。
            // 真正进入 GameScene 时，MenuManager.EnterGame 会补充 SongSelection 返回目标。
            PrepareGameLaunch(chapter, song, difficulty, MenuReturnDestination.None);
        }

        /// <summary>
        /// 统一准备一次 GameScene 运行所需的上下文。
        /// 普通选曲和 TutorialBlock 都必须通过此入口写入，防止章节、歌曲、难度与返回目标来自不同旧运行。
        /// </summary>
        public bool PrepareGameLaunch(ChapterSelectionUnit chapter, SongItemData song,
            DifficultyData difficulty, MenuReturnDestination returnDestination)
        {
            if (chapter == null || song == null || difficulty == null)
            {
                Debug.LogWarning("[InformationTransistor] 缺少章节、歌曲或难度，无法准备 GameScene 上下文。");
                return false;
            }

            this.chapter = chapter;
            this.song = song;
            this.difficulty = difficulty;
            chapterSwitch = chapter.chapterSwitch;
            songSwitch = song.songSwitch;
            menuReturnDestination = returnDestination;
            return true;
        }

        /// <summary>
        /// 由现有选曲过场在真正激活 GameScene 前设置返回目标。
        /// </summary>
        public void SetMenuReturnDestination(MenuReturnDestination returnDestination)
        {
            menuReturnDestination = returnDestination;
        }

        /// <summary>
        /// MenuScene 已依据返回目标完成恢复后调用。
        /// 只清除一次性路由，不清除歌曲与难度，以免当前 UI 的运行时缓存被意外破坏。
        /// </summary>
        public void ClearMenuReturnDestination()
        {
            menuReturnDestination = MenuReturnDestination.None;
        }
    }
}