ichni_Official/Assets/Scripts/UI/Prepare/PrepareUIPage.cs

using System.Collections;
using System.Collections.Generic;
using System.Linq;
using Ichni.Menu;
using Ichni.Story;
using TMPro;
using UnityEngine;
using UnityEngine.UI;

namespace Ichni.UI
{
    public partial class PrepareUIPage : UIPageBase
    {
        public Button enterGameButton;
        public Button switchDifficultyButton;

        public string songName;
        public List<string> difficulties;
        public string difficultyName;

        private ChapterSelectionUnit chapter;
        private SongItemData songItem;
        private DifficultyData difficultyData;
    }
    
    public partial class PrepareUIPage
    {
        public void SetUpPrepareUIPage(string songName)
        {
            chapter = ChapterSelectionManager.instance.chapters
                .FirstOrDefault(c => c.chapterIndex == ChapterSelectionManager.instance.currentChapter);
            songItem = chapter.songs.FirstOrDefault(s => s.songName == songName);
            
            this.songName = songName;
            this.difficulties = new List<string>();
            foreach (DifficultyData difficulty in songItem.difficultyDataList)
            {
                this.difficulties.Add(difficulty.difficultyName);
            }

            this.difficultyName = difficulties[0];
            
            difficultyData = songItem.difficultyDataList.FirstOrDefault(d => d.difficultyName == difficultyName);
            switchDifficultyButton.GetComponentInChildren<TMP_Text>().text = difficultyName + " Lv." + difficultyData.difficultyValue;
            switchDifficultyButton.GetComponentInChildren<TMP_Text>().color = difficultyData.color;
        }

        public void SwitchDifficulty()
        {
            int currentIndex = difficulties.IndexOf(difficultyName);
            int nextIndex = (currentIndex + 1) % difficulties.Count;
            difficultyName = difficulties[nextIndex];

            difficultyData = songItem.difficultyDataList
                .FirstOrDefault(d => d.difficultyName == difficultyName);
            
            switchDifficultyButton.GetComponentInChildren<TMP_Text>().text = difficultyName + " Lv." + difficultyData.difficultyValue;
            switchDifficultyButton.GetComponentInChildren<TMP_Text>().color = difficultyData.color;
        }
        
        public void EnterGame()
        {
            InformationTransistor.instance.SetInformation(
                ChapterSelectionManager.instance.currentChapter, 
                songItem.songName, 
                songItem.composer,
                difficultyName,
                songItem.illustratorName,
                difficultyData.displayDifficultyName,
                difficultyData.color, songItem.albumIllustrationCover,
                chapter.chapterSwitch, songItem.songSwitch);

            MenuManager.instance.TestEnterGame();
        }
    }
}