package funkin.ui.freeplay;

import flixel.addons.transition.FlxTransitionableState;
import flixel.FlxCamera;
import flixel.FlxSprite;
import flixel.group.FlxGroup;
import flixel.group.FlxGroup.FlxTypedGroup;
import flixel.group.FlxSpriteGroup.FlxTypedSpriteGroup;
import flixel.input.touch.FlxTouch;
import flixel.math.FlxAngle;
import flixel.math.FlxPoint;
import flixel.system.debug.watch.Tracker.TrackerProfile;
import flixel.text.FlxText;
import flixel.tweens.FlxEase;
import flixel.tweens.FlxTween;
import flixel.tweens.misc.ShakeTween;
import flixel.util.FlxColor;
import flixel.util.FlxSpriteUtil;
import flixel.util.FlxTimer;
import funkin.audio.FunkinSound;
import funkin.data.freeplay.player.PlayerRegistry;
import funkin.data.song.SongRegistry;
import funkin.data.story.level.LevelRegistry;
import funkin.effects.IntervalShake;
import funkin.graphics.adobeanimate.FlxAtlasSprite;
import funkin.graphics.FunkinCamera;
import funkin.graphics.FunkinSprite;
import funkin.graphics.shaders.AngleMask;
import funkin.graphics.shaders.GaussianBlurShader;
import funkin.graphics.shaders.HSVShader;
import funkin.graphics.shaders.PureColor;
import funkin.graphics.shaders.StrokeShader;
import funkin.input.Controls;
import funkin.play.PlayStatePlaylist;
import funkin.play.scoring.Scoring;
import funkin.play.scoring.Scoring.ScoringRank;
import funkin.play.song.Song;
import funkin.save.Save;
import funkin.save.Save.SaveScoreData;
import funkin.ui.AtlasText;
import funkin.ui.freeplay.charselect.PlayableCharacter;
import funkin.ui.freeplay.SongMenuItem.FreeplayRank;
import funkin.ui.mainmenu.MainMenuState;
import funkin.ui.MusicBeatSubState;
import funkin.ui.story.Level;
import funkin.ui.transition.LoadingState;
import funkin.ui.transition.StickerSubState;
import funkin.util.MathUtil;
import funkin.util.SortUtil;
import lime.utils.Assets;
import openfl.display.BlendMode;

/**
 * Parameters used to initialize the FreeplayState.
 */
typedef FreeplayStateParams =
{
  ?character:String,

  ?fromResults:FromResultsParams,
};

/**
 * A set of parameters for transitioning to the FreeplayState from the ResultsState.
 */
typedef FromResultsParams =
{
  /**
   * The previous rank the song hand, if any. Null if it had no score before.
   */
  var ?oldRank:ScoringRank;

  /**
   * Whether or not to play the rank animation on returning to freeplay.
   */
  var playRankAnim:Bool;

  /**
   * The new rank the song has.
   */
  var newRank:ScoringRank;

  /**
   * The song ID to play the animation on.
   */
  var songId:String;

  /**
   * The difficulty ID to play the animation on.
   */
  var difficultyId:String;
};

/**
 * The state for the freeplay menu, allowing the player to select any song to play.
 */
@:nullSafety
class FreeplayState extends MusicBeatSubState
{
  //
  // Params
  //

  /**
   * The current character for this FreeplayState.
   * You can't change this without transitioning to a new FreeplayState.
   */
  final currentCharacterId:String;

  final currentCharacter:PlayableCharacter;

  /**
   * For the audio preview, the duration of the fade-in effect.
   */
  public static final FADE_IN_DURATION:Float = 0.5;

  /**
   * For the audio preview, the duration of the fade-out effect.
   *
   */
  public static final FADE_OUT_DURATION:Float = 0.25;

  /**
   * For the audio preview, the volume at which the fade-in starts.
   */
  public static final FADE_IN_START_VOLUME:Float = 0.25;

  /**
   * For the audio preview, the volume at which the fade-in ends.
   */
  public static final FADE_IN_END_VOLUME:Float = 1.0;

  /**
   * For the audio preview, the volume at which the fade-out starts.
   */
  public static final FADE_OUT_END_VOLUME:Float = 0.0;

  var songs:Array<Null<FreeplaySongData>> = [];

  var diffIdsCurrent:Array<String> = [];
  var diffIdsTotal:Array<String> = [];

  var curSelected:Int = 0;
  var currentDifficulty:String = Constants.DEFAULT_DIFFICULTY;

  var fp:FreeplayScore;
  var txtCompletion:AtlasText;
  var lerpCompletion:Float = 0;
  var intendedCompletion:Float = 0;
  var lerpScore:Float = 0;
  var intendedScore:Int = 0;

  var grpDifficulties:FlxTypedSpriteGroup<DifficultySprite>;

  var coolColors:Array<Int> = [
    0xFF9271FD,
    0xFF9271FD,
    0xFF223344,
    0xFF941653,
    0xFFFC96D7,
    0xFFA0D1FF,
    0xFFFF78BF,
    0xFFF6B604
  ];

  var grpSongs:FlxTypedGroup<Alphabet>;
  var grpCapsules:FlxTypedGroup<SongMenuItem>;
  var curPlaying:Bool = false;

  var dj:Null<FreeplayDJ> = null;

  var ostName:FlxText;
  var albumRoll:AlbumRoll;

  var letterSort:LetterSort;
  var exitMovers:ExitMoverData = new Map();

  var stickerSubState:Null<StickerSubState> = null;

  /**
   * The difficulty we were on when this menu was last accessed.
   */
  public static var rememberedDifficulty:String = Constants.DEFAULT_DIFFICULTY;

  /**
   * The song we were on when this menu was last accessed.
   * NOTE: `null` if the last song was `Random`.
   */
  public static var rememberedSongId:Null<String> = 'tutorial';

  /**
   * The character we were on when this menu was last accessed.
   */
  public static var rememberedCharacterId:String = Constants.DEFAULT_CHARACTER;

  var funnyCam:FunkinCamera;
  var rankCamera:FunkinCamera;
  var rankBg:FunkinSprite;
  var rankVignette:FlxSprite;

  var backingTextYeah:FlxAtlasSprite;
  var orangeBackShit:FunkinSprite;
  var alsoOrangeLOL:FunkinSprite;
  var pinkBack:FunkinSprite;
  var confirmGlow:FlxSprite;
  var confirmGlow2:FlxSprite;
  var confirmTextGlow:FlxSprite;

  var moreWays:BGScrollingText;
  var funnyScroll:BGScrollingText;
  var txtNuts:BGScrollingText;
  var funnyScroll2:BGScrollingText;
  var moreWays2:BGScrollingText;
  var funnyScroll3:BGScrollingText;

  var bgDad:FlxSprite;
  var cardGlow:FlxSprite;

  var fromResultsParams:Null<FromResultsParams> = null;

  var prepForNewRank:Bool = false;

  public function new(?params:FreeplayStateParams, ?stickers:StickerSubState)
  {
    currentCharacterId = params?.character ?? rememberedCharacterId;
    var fetchPlayableCharacter = function():PlayableCharacter {
      var result = PlayerRegistry.instance.fetchEntry(params?.character ?? rememberedCharacterId);
      if (result == null) throw 'No valid playable character with id ${params?.character}';
      return result;
    };
    currentCharacter = fetchPlayableCharacter();

    rememberedCharacterId = currentCharacter?.id ?? Constants.DEFAULT_CHARACTER;

    fromResultsParams = params?.fromResults;

    if (fromResultsParams?.playRankAnim == true)
    {
      prepForNewRank = true;
    }

    super(FlxColor.TRANSPARENT);

    if (stickers?.members != null)
    {
      stickerSubState = stickers;
    }

    // We build a bunch of sprites BEFORE create() so we can guarantee they aren't null later on.
    albumRoll = new AlbumRoll();
    fp = new FreeplayScore(460, 60, 7, 100);
    cardGlow = new FlxSprite(-30, -30).loadGraphic(Paths.image('freeplay/cardGlow'));
    confirmGlow = new FlxSprite(-30, 240).loadGraphic(Paths.image('freeplay/confirmGlow'));
    confirmTextGlow = new FlxSprite(-8, 115).loadGraphic(Paths.image('freeplay/glowingText'));
    rankCamera = new FunkinCamera('rankCamera', 0, 0, FlxG.width, FlxG.height);
    funnyCam = new FunkinCamera('freeplayFunny', 0, 0, FlxG.width, FlxG.height);
    funnyScroll = new BGScrollingText(0, 220, currentCharacter.getFreeplayDJText(1), FlxG.width / 2, false, 60);
    funnyScroll2 = new BGScrollingText(0, 335, currentCharacter.getFreeplayDJText(1), FlxG.width / 2, false, 60);
    grpCapsules = new FlxTypedGroup<SongMenuItem>();
    grpDifficulties = new FlxTypedSpriteGroup<DifficultySprite>(-300, 80);
    letterSort = new LetterSort(400, 75);
    grpSongs = new FlxTypedGroup<Alphabet>();
    moreWays = new BGScrollingText(0, 160, currentCharacter.getFreeplayDJText(2), FlxG.width, true, 43);
    moreWays2 = new BGScrollingText(0, 397, currentCharacter.getFreeplayDJText(2), FlxG.width, true, 43);
    pinkBack = FunkinSprite.create('freeplay/pinkBack');
    rankBg = new FunkinSprite(0, 0);
    rankVignette = new FlxSprite(0, 0).loadGraphic(Paths.image('freeplay/rankVignette'));
    sparks = new FlxSprite(0, 0);
    sparksADD = new FlxSprite(0, 0);
    txtCompletion = new AtlasText(1185, 87, '69', AtlasFont.FREEPLAY_CLEAR);
    txtNuts = new BGScrollingText(0, 285, currentCharacter.getFreeplayDJText(3), FlxG.width / 2, true, 43);

    ostName = new FlxText(8, 8, FlxG.width - 8 - 8, 'OFFICIAL OST', 48);

    orangeBackShit = new FunkinSprite(84, 440).makeSolidColor(Std.int(pinkBack.width), 75, 0xFFFEDA00);

    bgDad = new FlxSprite(pinkBack.width * 0.74, 0).loadGraphic(Paths.image('freeplay/freeplayBGdad'));
    alsoOrangeLOL = new FunkinSprite(0, orangeBackShit.y).makeSolidColor(100, Std.int(orangeBackShit.height), 0xFFFFD400);
    confirmGlow2 = new FlxSprite(confirmGlow.x, confirmGlow.y).loadGraphic(Paths.image('freeplay/confirmGlow2'));
    funnyScroll3 = new BGScrollingText(0, orangeBackShit.y + 10, currentCharacter.getFreeplayDJText(1), FlxG.width / 2, 60);
    backingTextYeah = new FlxAtlasSprite(640, 370, Paths.animateAtlas("freeplay/backing-text-yeah"),
      {
        FrameRate: 24.0,
        Reversed: false,
        // ?OnComplete:Void -> Void,
        ShowPivot: false,
        Antialiasing: true,
        ScrollFactor: new FlxPoint(1, 1),
      });
  }

  override function create():Void
  {
    super.create();

    FlxG.state.persistentUpdate = false;

    FlxTransitionableState.skipNextTransIn = true;

    if (stickerSubState != null)
    {
      this.persistentUpdate = true;
      this.persistentDraw = true;

      openSubState(stickerSubState);
      stickerSubState.degenStickers();
    }

    #if FEATURE_DISCORD_RPC
    // Updating Discord Rich Presence
    DiscordClient.changePresence('In the Menus', null);
    #end

    var isDebug:Bool = false;

    #if FEATURE_DEBUG_FUNCTIONS
    isDebug = true;
    #end

    if (prepForNewRank == false)
    {
      FunkinSound.playMusic('freakyMenu',
        {
          overrideExisting: true,
          restartTrack: false
        });
    }

    // Add a null entry that represents the RANDOM option
    songs.push(null);

    // programmatically adds the songs via LevelRegistry and SongRegistry
    for (levelId in LevelRegistry.instance.listSortedLevelIds())
    {
      var level:Null<Level> = LevelRegistry.instance.fetchEntry(levelId);

      if (level == null)
      {
        trace('[WARN] Could not find level with id (${levelId})');
        continue;
      }

      for (songId in level.getSongs())
      {
        var song:Null<Song> = SongRegistry.instance.fetchEntry(songId);

        if (song == null)
        {
          trace('[WARN] Could not find song with id (${songId})');
          continue;
        }

        // Only display songs which actually have available difficulties for the current character.
        var displayedVariations = song.getVariationsByCharacter(currentCharacter);
        trace('Displayed Variations (${songId}): $displayedVariations');
        var availableDifficultiesForSong:Array<String> = song.listSuffixedDifficulties(displayedVariations, false, false);
        trace('Available Difficulties: $availableDifficultiesForSong');
        if (availableDifficultiesForSong.length == 0) continue;

        songs.push(new FreeplaySongData(levelId, songId, song, displayedVariations));
        for (difficulty in availableDifficultiesForSong)
        {
          diffIdsTotal.pushUnique(difficulty);
        }
      }
    }

    // LOAD MUSIC

    // LOAD CHARACTERS

    trace(FlxG.width);
    trace(FlxG.camera.zoom);
    trace(FlxG.camera.initialZoom);
    trace(FlxCamera.defaultZoom);

    pinkBack.color = 0xFFFFD4E9; // sets it to pink!
    pinkBack.x -= pinkBack.width;

    FlxTween.tween(pinkBack, {x: 0}, 0.6, {ease: FlxEase.quartOut});
    add(pinkBack);

    add(orangeBackShit);

    add(alsoOrangeLOL);

    exitMovers.set([pinkBack, orangeBackShit, alsoOrangeLOL],
      {
        x: -pinkBack.width,
        y: pinkBack.y,
        speed: 0.4,
        wait: 0
      });

    FlxSpriteUtil.alphaMaskFlxSprite(orangeBackShit, pinkBack, orangeBackShit);
    orangeBackShit.visible = false;
    alsoOrangeLOL.visible = false;

    confirmTextGlow.blend = BlendMode.ADD;
    confirmTextGlow.visible = false;

    confirmGlow.blend = BlendMode.ADD;

    confirmGlow.visible = false;
    confirmGlow2.visible = false;

    add(confirmGlow2);
    add(confirmGlow);

    add(confirmTextGlow);

    var grpTxtScrolls:FlxGroup = new FlxGroup();
    add(grpTxtScrolls);
    grpTxtScrolls.visible = false;

    FlxG.debugger.addTrackerProfile(new TrackerProfile(BGScrollingText, ['x', 'y', 'speed', 'size']));

    moreWays.funnyColor = 0xFFFFF383;
    moreWays.speed = 6.8;
    grpTxtScrolls.add(moreWays);

    exitMovers.set([moreWays],
      {
        x: FlxG.width * 2,
        speed: 0.4,
      });

    funnyScroll.funnyColor = 0xFFFF9963;
    funnyScroll.speed = -3.8;
    grpTxtScrolls.add(funnyScroll);

    exitMovers.set([funnyScroll],
      {
        x: -funnyScroll.width * 2,
        y: funnyScroll.y,
        speed: 0.4,
        wait: 0
      });

    txtNuts.speed = 3.5;
    grpTxtScrolls.add(txtNuts);
    exitMovers.set([txtNuts],
      {
        x: FlxG.width * 2,
        speed: 0.4,
      });

    funnyScroll2.funnyColor = 0xFFFF9963;
    funnyScroll2.speed = -3.8;
    grpTxtScrolls.add(funnyScroll2);

    exitMovers.set([funnyScroll2],
      {
        x: -funnyScroll2.width * 2,
        speed: 0.5,
      });

    moreWays2.funnyColor = 0xFFFFF383;
    moreWays2.speed = 6.8;
    grpTxtScrolls.add(moreWays2);

    exitMovers.set([moreWays2],
      {
        x: FlxG.width * 2,
        speed: 0.4
      });

    funnyScroll3.funnyColor = 0xFFFEA400;
    funnyScroll3.speed = -3.8;
    grpTxtScrolls.add(funnyScroll3);

    exitMovers.set([funnyScroll3],
      {
        x: -funnyScroll3.width * 2,
        speed: 0.3
      });

    add(backingTextYeah);

    cardGlow.blend = BlendMode.ADD;
    cardGlow.visible = false;

    add(cardGlow);

    if (currentCharacter?.getFreeplayDJData() != null)
    {
      dj = new FreeplayDJ(640, 366, currentCharacterId);
      exitMovers.set([dj],
        {
          x: -dj.width * 1.6,
          speed: 0.5
        });
      add(dj);
    }

    bgDad.shader = new AngleMask();
    bgDad.visible = false;

    var blackOverlayBullshitLOLXD:FlxSprite = new FlxSprite(FlxG.width).makeGraphic(Std.int(bgDad.width), Std.int(bgDad.height), FlxColor.BLACK);
    add(blackOverlayBullshitLOLXD); // used to mask the text lol!

    // this makes the texture sizes consistent, for the angle shader
    bgDad.setGraphicSize(0, FlxG.height);
    blackOverlayBullshitLOLXD.setGraphicSize(0, FlxG.height);

    bgDad.updateHitbox();
    blackOverlayBullshitLOLXD.updateHitbox();

    exitMovers.set([blackOverlayBullshitLOLXD, bgDad],
      {
        x: FlxG.width * 1.5,
        speed: 0.4,
        wait: 0
      });

    add(bgDad);
    FlxTween.tween(blackOverlayBullshitLOLXD, {x: pinkBack.width * 0.74}, 0.7, {ease: FlxEase.quintOut});

    blackOverlayBullshitLOLXD.shader = bgDad.shader;

    rankBg.makeSolidColor(FlxG.width, FlxG.height, 0xD3000000);
    add(rankBg);

    add(grpSongs);

    add(grpCapsules);

    add(grpDifficulties);

    exitMovers.set([grpDifficulties],
      {
        x: -300,
        speed: 0.25,
        wait: 0
      });

    for (diffId in diffIdsTotal)
    {
      var diffSprite:DifficultySprite = new DifficultySprite(diffId);
      diffSprite.difficultyId = diffId;
      grpDifficulties.add(diffSprite);
    }

    grpDifficulties.group.forEach(function(spr) {
      spr.visible = false;
    });

    for (diffSprite in grpDifficulties.group.members)
    {
      if (diffSprite == null) continue;
      if (diffSprite.difficultyId == currentDifficulty) diffSprite.visible = true;
    }

    albumRoll.albumId = null;
    add(albumRoll);

    albumRoll.applyExitMovers(exitMovers);

    var overhangStuff:FlxSprite = new FlxSprite().makeGraphic(FlxG.width, 64, FlxColor.BLACK);
    overhangStuff.y -= overhangStuff.height;
    add(overhangStuff);
    FlxTween.tween(overhangStuff, {y: 0}, 0.3, {ease: FlxEase.quartOut});

    var fnfFreeplay:FlxText = new FlxText(8, 8, 0, 'FREEPLAY', 48);
    fnfFreeplay.font = 'VCR OSD Mono';
    fnfFreeplay.visible = false;

    ostName.font = 'VCR OSD Mono';
    ostName.alignment = RIGHT;
    ostName.visible = false;

    exitMovers.set([overhangStuff, fnfFreeplay, ostName],
      {
        y: -overhangStuff.height,
        x: 0,
        speed: 0.2,
        wait: 0
      });

    var sillyStroke:StrokeShader = new StrokeShader(0xFFFFFFFF, 2, 2);
    fnfFreeplay.shader = sillyStroke;
    ostName.shader = sillyStroke;
    add(fnfFreeplay);
    add(ostName);

    var fnfHighscoreSpr:FlxSprite = new FlxSprite(860, 70);
    fnfHighscoreSpr.frames = Paths.getSparrowAtlas('freeplay/highscore');
    fnfHighscoreSpr.animation.addByPrefix('highscore', 'highscore small instance 1', 24, false);
    fnfHighscoreSpr.visible = false;
    fnfHighscoreSpr.setGraphicSize(0, Std.int(fnfHighscoreSpr.height * 1));
    fnfHighscoreSpr.updateHitbox();
    add(fnfHighscoreSpr);

    new FlxTimer().start(FlxG.random.float(12, 50), function(tmr) {
      fnfHighscoreSpr.animation.play('highscore');
      tmr.time = FlxG.random.float(20, 60);
    }, 0);

    fp.visible = false;
    add(fp);

    var clearBoxSprite:FlxSprite = new FlxSprite(1165, 65).loadGraphic(Paths.image('freeplay/clearBox'));
    clearBoxSprite.visible = false;
    add(clearBoxSprite);

    txtCompletion.visible = false;
    add(txtCompletion);

    add(letterSort);
    letterSort.visible = false;

    exitMovers.set([letterSort],
      {
        y: -100,
        speed: 0.3
      });

    letterSort.changeSelectionCallback = (str) -> {
      switch (str)
      {
        case 'fav':
          generateSongList({filterType: FAVORITE}, true);
        case 'ALL':
          generateSongList(null, true);
        case '#':
          generateSongList({filterType: REGEXP, filterData: '0-9'}, true);
        default:
          generateSongList({filterType: REGEXP, filterData: str}, true);
      }

      // We want to land on the first song of the group, rather than random song when changing letter sorts
      // that is, only if there's more than one song in the group!
      if (grpCapsules.members.length > 0)
      {
        FunkinSound.playOnce(Paths.sound('scrollMenu'), 0.4);
        curSelected = 1;
        changeSelection();
      }
    };

    exitMovers.set([fp, txtCompletion, fnfHighscoreSpr, txtCompletion, clearBoxSprite],
      {
        x: FlxG.width,
        speed: 0.3
      });

    var diffSelLeft:DifficultySelector = new DifficultySelector(this, 20, grpDifficulties.y - 10, false, controls);
    var diffSelRight:DifficultySelector = new DifficultySelector(this, 325, grpDifficulties.y - 10, true, controls);
    diffSelLeft.visible = false;
    diffSelRight.visible = false;
    add(diffSelLeft);
    add(diffSelRight);

    // be careful not to "add()" things in here unless it's to a group that's already added to the state
    // otherwise it won't be properly attatched to funnyCamera (relavent code should be at the bottom of create())
    var onDJIntroDone = function() {
      // when boyfriend hits dat shiii

      albumRoll.playIntro();

      FlxTween.tween(grpDifficulties, {x: 90}, 0.6, {ease: FlxEase.quartOut});

      diffSelLeft.visible = true;
      diffSelRight.visible = true;
      letterSort.visible = true;

      exitMovers.set([diffSelLeft, diffSelRight],
        {
          x: -diffSelLeft.width * 2,
          speed: 0.26
        });

      new FlxTimer().start(1 / 24, function(handShit) {
        fnfHighscoreSpr.visible = true;
        fnfFreeplay.visible = true;
        ostName.visible = true;
        fp.visible = true;
        fp.updateScore(0);

        clearBoxSprite.visible = true;
        txtCompletion.visible = true;
        intendedCompletion = 0;

        new FlxTimer().start(1.5 / 24, function(bold) {
          sillyStroke.width = 0;
          sillyStroke.height = 0;
          changeSelection();
        });
      });

      pinkBack.color = 0xFFFFD863;
      bgDad.visible = true;
      orangeBackShit.visible = true;
      alsoOrangeLOL.visible = true;
      grpTxtScrolls.visible = true;

      // render optimisation
      if (_parentState != null) _parentState.persistentDraw = false;

      cardGlow.visible = true;
      FlxTween.tween(cardGlow, {alpha: 0, "scale.x": 1.2, "scale.y": 1.2}, 0.45, {ease: FlxEase.sineOut});

      if (prepForNewRank && fromResultsParams != null)
      {
        rankAnimStart(fromResultsParams);
      }
    };

    if (dj != null)
    {
      dj.onIntroDone.add(onDJIntroDone);
    }
    else
    {
      onDJIntroDone();
    }

    generateSongList(null, false);

    // dedicated camera for the state so we don't need to fuk around with camera scrolls from the mainmenu / elsewhere
    funnyCam.bgColor = FlxColor.TRANSPARENT;
    FlxG.cameras.add(funnyCam, false);

    rankVignette.scale.set(2, 2);
    rankVignette.updateHitbox();
    rankVignette.blend = BlendMode.ADD;
    // rankVignette.cameras = [rankCamera];
    add(rankVignette);
    rankVignette.alpha = 0;

    forEach(function(bs) {
      bs.cameras = [funnyCam];
    });

    rankCamera.bgColor = FlxColor.TRANSPARENT;
    FlxG.cameras.add(rankCamera, false);
    rankBg.cameras = [rankCamera];
    rankBg.alpha = 0;

    if (prepForNewRank)
    {
      rankCamera.fade(0xFF000000, 0, false, null, true);
    }
  }

  var currentFilter:Null<SongFilter> = null;
  var currentFilteredSongs:Array<Null<FreeplaySongData>> = [];

  /**
   * Given the current filter, rebuild the current song list.
   *
   * @param filterStuff A filter to apply to the song list (regex, startswith, all, favorite)
   * @param force Whether the capsules should "jump" back in or not using their animation
   * @param onlyIfChanged Only apply the filter if the song list has changed
   */
  public function generateSongList(filterStuff:Null<SongFilter>, force:Bool = false, onlyIfChanged:Bool = true):Void
  {
    var tempSongs:Array<Null<FreeplaySongData>> = songs;

    // Remember just the difficulty because it's important for song sorting.
    currentDifficulty = rememberedDifficulty;

    if (filterStuff != null) tempSongs = sortSongs(tempSongs, filterStuff);

    // Filter further by current selected difficulty.
    if (currentDifficulty != null)
    {
      tempSongs = tempSongs.filter(song -> {
        if (song == null) return true; // Random
        return song.songDifficulties.contains(currentDifficulty);
      });
    }

    if (onlyIfChanged)
    {
      // == performs equality by reference
      if (tempSongs.isEqualUnordered(currentFilteredSongs)) return;
    }

    // Only now do we know that the filter is actually changing.

    // If curSelected is 0, the result will be null and fall back to the rememberedSongId.
    rememberedSongId = grpCapsules.members[curSelected]?.songData?.songId ?? rememberedSongId;

    for (cap in grpCapsules.members)
    {
      cap.songText.resetText();
      cap.kill();
    }

    currentFilter = filterStuff;

    currentFilteredSongs = tempSongs;
    curSelected = 0;

    var hsvShader:HSVShader = new HSVShader();

    var randomCapsule:SongMenuItem = grpCapsules.recycle(SongMenuItem);
    randomCapsule.init(FlxG.width, 0, null);
    randomCapsule.onConfirm = function() {
      capsuleOnConfirmRandom(randomCapsule);
    };
    randomCapsule.y = randomCapsule.intendedY(0) + 10;
    randomCapsule.targetPos.x = randomCapsule.x;
    randomCapsule.alpha = 0;
    randomCapsule.songText.visible = false;
    randomCapsule.favIcon.visible = false;
    randomCapsule.favIconBlurred.visible = false;
    randomCapsule.ranking.visible = false;
    randomCapsule.blurredRanking.visible = false;
    randomCapsule.initJumpIn(0, force);
    randomCapsule.hsvShader = hsvShader;
    grpCapsules.add(randomCapsule);

    for (i in 0...tempSongs.length)
    {
      var tempSong = tempSongs[i];
      if (tempSong == null) continue;

      var funnyMenu:SongMenuItem = grpCapsules.recycle(SongMenuItem);

      funnyMenu.init(FlxG.width, 0, tempSong);
      funnyMenu.onConfirm = function() {
        capsuleOnConfirmDefault(funnyMenu);
      };
      funnyMenu.y = funnyMenu.intendedY(i + 1) + 10;
      funnyMenu.targetPos.x = funnyMenu.x;
      funnyMenu.ID = i;
      funnyMenu.capsule.alpha = 0.5;
      funnyMenu.songText.visible = false;
      funnyMenu.favIcon.visible = tempSong.isFav;
      funnyMenu.favIconBlurred.visible = tempSong.isFav;
      funnyMenu.hsvShader = hsvShader;

      funnyMenu.newText.animation.curAnim.curFrame = 45 - ((i * 4) % 45);
      funnyMenu.checkClip();
      funnyMenu.forcePosition();

      grpCapsules.add(funnyMenu);
    }

    FlxG.console.registerFunction('changeSelection', changeSelection);

    rememberSelection();

    changeSelection();
    changeDiff(0, true);
  }

  /**
   * Filters an array of songs based on a filter
   * @param songsToFilter What data to use when filtering
   * @param songFilter The filter to apply
   * @return Array<FreeplaySongData>
   */
  public function sortSongs(songsToFilter:Array<Null<FreeplaySongData>>, songFilter:SongFilter):Array<Null<FreeplaySongData>>
  {
    var filterAlphabetically = function(a:Null<FreeplaySongData>, b:Null<FreeplaySongData>):Int {
      return SortUtil.alphabetically(a?.songName ?? '', b?.songName ?? '');
    };

    switch (songFilter.filterType)
    {
      case REGEXP:
        // filterStuff.filterData has a string with the first letter of the sorting range, and the second one
        // this creates a filter to return all the songs that start with a letter between those two

        // if filterData looks like "A-C", the regex should look something like this: ^[A-C].*
        // to get every song that starts between A and C
        var filterRegexp:EReg = new EReg('^[' + songFilter.filterData + '].*', 'i');
        songsToFilter = songsToFilter.filter(str -> {
          if (str == null) return true; // Random
          return filterRegexp.match(str.songName);
        });

        songsToFilter.sort(filterAlphabetically);

      case STARTSWITH:
        // extra note: this is essentially a "search"

        songsToFilter = songsToFilter.filter(str -> {
          if (str == null) return true; // Random
          return str.songName.toLowerCase().startsWith(songFilter.filterData ?? '');
        });
      case ALL:
        // no filter!
      case FAVORITE:
        songsToFilter = songsToFilter.filter(str -> {
          if (str == null) return true; // Random
          return str.isFav;
        });

        songsToFilter.sort(filterAlphabetically);

      default:
        // return all on default
    }

    return songsToFilter;
  }

  var sparks:FlxSprite;
  var sparksADD:FlxSprite;

  function rankAnimStart(fromResults:FromResultsParams):Void
  {
    busy = true;
    grpCapsules.members[curSelected].sparkle.alpha = 0;
    // grpCapsules.members[curSelected].forcePosition();

    rememberedSongId = fromResults.songId;
    rememberedDifficulty = fromResults.difficultyId;
    changeSelection();
    changeDiff();

    if (fromResultsParams?.newRank == SHIT)
    {
      if (dj != null) dj.fistPumpLossIntro();
    }
    else
    {
      if (dj != null) dj.fistPumpIntro();
    }

    // rankCamera.fade(FlxColor.BLACK, 0.5, true);
    rankCamera.fade(0xFF000000, 0.5, true, null, true);
    if (FlxG.sound.music != null) FlxG.sound.music.volume = 0;
    rankBg.alpha = 1;

    if (fromResults.oldRank != null)
    {
      grpCapsules.members[curSelected].fakeRanking.rank = fromResults.oldRank;
      grpCapsules.members[curSelected].fakeBlurredRanking.rank = fromResults.oldRank;

      sparks.frames = Paths.getSparrowAtlas('freeplay/sparks');
      sparks.animation.addByPrefix('sparks', 'sparks', 24, false);
      sparks.visible = false;
      sparks.blend = BlendMode.ADD;
      sparks.setPosition(517, 134);
      sparks.scale.set(0.5, 0.5);
      add(sparks);
      sparks.cameras = [rankCamera];

      sparksADD.visible = false;
      sparksADD.frames = Paths.getSparrowAtlas('freeplay/sparksadd');
      sparksADD.animation.addByPrefix('sparks add', 'sparks add', 24, false);
      sparksADD.setPosition(498, 116);
      sparksADD.blend = BlendMode.ADD;
      sparksADD.scale.set(0.5, 0.5);
      add(sparksADD);
      sparksADD.cameras = [rankCamera];

      switch (fromResults.oldRank)
      {
        case SHIT:
          sparksADD.color = 0xFF6044FF;
        case GOOD:
          sparksADD.color = 0xFFEF8764;
        case GREAT:
          sparksADD.color = 0xFFEAF6FF;
        case EXCELLENT:
          sparksADD.color = 0xFFFDCB42;
        case PERFECT:
          sparksADD.color = 0xFFFF58B4;
        case PERFECT_GOLD:
          sparksADD.color = 0xFFFFB619;
      }
      // sparksADD.color = sparks.color;
    }

    grpCapsules.members[curSelected].doLerp = false;

    // originalPos.x = grpCapsules.members[curSelected].x;
    // originalPos.y = grpCapsules.members[curSelected].y;

    originalPos.x = 320.488;
    originalPos.y = 235.6;
    trace(originalPos);

    grpCapsules.members[curSelected].ranking.visible = false;
    grpCapsules.members[curSelected].blurredRanking.visible = false;

    rankCamera.zoom = 1.85;
    FlxTween.tween(rankCamera, {"zoom": 1.8}, 0.6, {ease: FlxEase.sineIn});

    funnyCam.zoom = 1.15;
    FlxTween.tween(funnyCam, {"zoom": 1.1}, 0.6, {ease: FlxEase.sineIn});

    grpCapsules.members[curSelected].cameras = [rankCamera];
    // grpCapsules.members[curSelected].targetPos.set((FlxG.width / 2) - (grpCapsules.members[curSelected].width / 2),
    //  (FlxG.height / 2) - (grpCapsules.members[curSelected].height / 2));

    grpCapsules.members[curSelected].setPosition((FlxG.width / 2) - (grpCapsules.members[curSelected].width / 2),
      (FlxG.height / 2) - (grpCapsules.members[curSelected].height / 2));

    new FlxTimer().start(0.5, _ -> {
      rankDisplayNew(fromResults);
    });
  }

  function rankDisplayNew(fromResults:Null<FromResultsParams>):Void
  {
    grpCapsules.members[curSelected].ranking.visible = true;
    grpCapsules.members[curSelected].blurredRanking.visible = true;
    grpCapsules.members[curSelected].ranking.scale.set(20, 20);
    grpCapsules.members[curSelected].blurredRanking.scale.set(20, 20);

    if (fromResults != null && fromResults.newRank != null)
    {
      grpCapsules.members[curSelected].ranking.animation.play(fromResults.newRank.getFreeplayRankIconAsset(), true);
    }

    FlxTween.tween(grpCapsules.members[curSelected].ranking, {"scale.x": 1, "scale.y": 1}, 0.1);

    if (fromResults != null && fromResults.newRank != null)
    {
      grpCapsules.members[curSelected].blurredRanking.animation.play(fromResults.newRank.getFreeplayRankIconAsset(), true);
    }
    FlxTween.tween(grpCapsules.members[curSelected].blurredRanking, {"scale.x": 1, "scale.y": 1}, 0.1);

    new FlxTimer().start(0.1, _ -> {
      if (fromResults?.oldRank != null)
      {
        grpCapsules.members[curSelected].fakeRanking.visible = false;
        grpCapsules.members[curSelected].fakeBlurredRanking.visible = false;

        sparks.visible = true;
        sparksADD.visible = true;
        sparks.animation.play('sparks', true);
        sparksADD.animation.play('sparks add', true);

        sparks.animation.finishCallback = anim -> {
          sparks.visible = false;
          sparksADD.visible = false;
        };
      }

      switch (fromResultsParams?.newRank)
      {
        case SHIT:
          FunkinSound.playOnce(Paths.sound('ranks/rankinbad'));
        case PERFECT:
          FunkinSound.playOnce(Paths.sound('ranks/rankinperfect'));
        case PERFECT_GOLD:
          FunkinSound.playOnce(Paths.sound('ranks/rankinperfect'));
        default:
          FunkinSound.playOnce(Paths.sound('ranks/rankinnormal'));
      }
      rankCamera.zoom = 1.3;

      FlxTween.tween(rankCamera, {"zoom": 1.5}, 0.3, {ease: FlxEase.backInOut});

      grpCapsules.members[curSelected].x -= 10;
      grpCapsules.members[curSelected].y -= 20;

      FlxTween.tween(funnyCam, {"zoom": 1.05}, 0.3, {ease: FlxEase.elasticOut});

      grpCapsules.members[curSelected].capsule.angle = -3;
      FlxTween.tween(grpCapsules.members[curSelected].capsule, {angle: 0}, 0.5, {ease: FlxEase.backOut});

      IntervalShake.shake(grpCapsules.members[curSelected].capsule, 0.3, 1 / 30, 0.1, 0, FlxEase.quadOut);
    });

    new FlxTimer().start(0.4, _ -> {
      FlxTween.tween(funnyCam, {"zoom": 1}, 0.8, {ease: FlxEase.sineIn});
      FlxTween.tween(rankCamera, {"zoom": 1.2}, 0.8, {ease: FlxEase.backIn});
      FlxTween.tween(grpCapsules.members[curSelected], {x: originalPos.x - 7, y: originalPos.y - 80}, 0.8 + 0.5, {ease: FlxEase.quartIn});
    });

    new FlxTimer().start(0.6, _ -> {
      rankAnimSlam(fromResults);
    });
  }

  function rankAnimSlam(fromResultsParams:Null<FromResultsParams>)
  {
    // FlxTween.tween(rankCamera, {"zoom": 1.9}, 0.5, {ease: FlxEase.backOut});
    FlxTween.tween(rankBg, {alpha: 0}, 0.5, {ease: FlxEase.expoIn});

    // FlxTween.tween(grpCapsules.members[curSelected], {angle: 5}, 0.5, {ease: FlxEase.backIn});

    switch (fromResultsParams?.newRank)
    {
      case SHIT:
        FunkinSound.playOnce(Paths.sound('ranks/loss'));
      case GOOD:
        FunkinSound.playOnce(Paths.sound('ranks/good'));
      case GREAT:
        FunkinSound.playOnce(Paths.sound('ranks/great'));
      case EXCELLENT:
        FunkinSound.playOnce(Paths.sound('ranks/excellent'));
      case PERFECT:
        FunkinSound.playOnce(Paths.sound('ranks/perfect'));
      case PERFECT_GOLD:
        FunkinSound.playOnce(Paths.sound('ranks/perfect'));
      default:
        FunkinSound.playOnce(Paths.sound('ranks/loss'));
    }

    FlxTween.tween(grpCapsules.members[curSelected], {"targetPos.x": originalPos.x, "targetPos.y": originalPos.y}, 0.5, {ease: FlxEase.expoOut});
    new FlxTimer().start(0.5, _ -> {
      funnyCam.shake(0.0045, 0.35);

      if (fromResultsParams?.newRank == SHIT)
      {
        if (dj != null) dj.fistPumpLoss();
      }
      else
      {
        if (dj != null) dj.fistPump();
      }

      rankCamera.zoom = 0.8;
      funnyCam.zoom = 0.8;
      FlxTween.tween(rankCamera, {"zoom": 1}, 1, {ease: FlxEase.elasticOut});
      FlxTween.tween(funnyCam, {"zoom": 1}, 0.8, {ease: FlxEase.elasticOut});

      for (index => capsule in grpCapsules.members)
      {
        var distFromSelected:Float = Math.abs(index - curSelected) - 1;

        if (distFromSelected < 5)
        {
          if (index == curSelected)
          {
            FlxTween.cancelTweensOf(capsule);
            // capsule.targetPos.x += 50;
            capsule.fadeAnim();

            rankVignette.color = capsule.getTrailColor();
            rankVignette.alpha = 1;
            FlxTween.tween(rankVignette, {alpha: 0}, 0.6, {ease: FlxEase.expoOut});

            capsule.doLerp = false;
            capsule.setPosition(originalPos.x, originalPos.y);
            IntervalShake.shake(capsule, 0.6, 1 / 24, 0.12, 0, FlxEase.quadOut, function(_) {
              capsule.doLerp = true;
              capsule.cameras = [funnyCam];

              // NOW we can interact with the menu
              busy = false;
              capsule.sparkle.alpha = 0.7;
              playCurSongPreview(capsule);
            }, null);

            // FlxTween.tween(capsule, {"targetPos.x": capsule.targetPos.x - 50}, 0.6,
            //   {
            //     ease: FlxEase.backInOut,
            //     onComplete: function(_) {
            //       capsule.cameras = [funnyCam];
            //     }
            //   });
            FlxTween.tween(capsule, {angle: 0}, 0.5, {ease: FlxEase.backOut});
          }
          if (index > curSelected)
          {
            // capsule.color = FlxColor.RED;
            new FlxTimer().start(distFromSelected / 20, _ -> {
              capsule.doLerp = false;

              capsule.capsule.angle = FlxG.random.float(-10 + (distFromSelected * 2), 10 - (distFromSelected * 2));
              FlxTween.tween(capsule.capsule, {angle: 0}, 0.5, {ease: FlxEase.backOut});

              IntervalShake.shake(capsule, 0.6, 1 / 24, 0.12 / (distFromSelected + 1), 0, FlxEase.quadOut, function(_) {
                capsule.doLerp = true;
              });
            });
          }

          if (index < curSelected)
          {
            // capsule.color = FlxColor.BLUE;
            new FlxTimer().start(distFromSelected / 20, _ -> {
              capsule.doLerp = false;

              capsule.capsule.angle = FlxG.random.float(-10 + (distFromSelected * 2), 10 - (distFromSelected * 2));
              FlxTween.tween(capsule.capsule, {angle: 0}, 0.5, {ease: FlxEase.backOut});

              IntervalShake.shake(capsule, 0.6, 1 / 24, 0.12 / (distFromSelected + 1), 0, FlxEase.quadOut, function(_) {
                capsule.doLerp = true;
              });
            });
          }
        }

        index += 1;
      }
    });

    new FlxTimer().start(2, _ -> {
      // dj.fistPump();
      prepForNewRank = false;
    });
  }

  var touchY:Float = 0;
  var touchX:Float = 0;
  var dxTouch:Float = 0;
  var dyTouch:Float = 0;
  var velTouch:Float = 0;

  var veloctiyLoopShit:Float = 0;
  var touchTimer:Float = 0;

  var initTouchPos:FlxPoint = new FlxPoint();

  var spamTimer:Float = 0;
  var spamming:Bool = false;

  /**
   * If true, disable interaction with the interface.
   */
  public var busy:Bool = false;

  var originalPos:FlxPoint = new FlxPoint();

  override function update(elapsed:Float):Void
  {
    super.update(elapsed);

    #if FEATURE_DEBUG_FUNCTIONS
    if (FlxG.keys.justPressed.T)
    {
      rankAnimStart(fromResultsParams ??
        {
          playRankAnim: true,
          newRank: PERFECT_GOLD,
          songId: "tutorial",
          difficultyId: "hard"
        });
    }

    if (FlxG.keys.justPressed.P)
    {
      FlxG.switchState(FreeplayState.build(
        {
          {
            character: currentCharacterId == "pico" ? "bf" : "pico",
          }
        }));
    }

    // if (FlxG.keys.justPressed.H)
    // {
    //   rankDisplayNew(fromResultsParams);
    // }

    // if (FlxG.keys.justPressed.G)
    // {
    //   rankAnimSlam(fromResultsParams);
    // }
    #end

    if (controls.FREEPLAY_CHAR_SELECT && !busy)
    {
      FlxG.switchState(new funkin.ui.charSelect.CharSelectSubState());
    }

    if (controls.FREEPLAY_FAVORITE && !busy)
    {
      var targetSong = grpCapsules.members[curSelected]?.songData;
      if (targetSong != null)
      {
        var realShit:Int = curSelected;
        var isFav = targetSong.toggleFavorite();
        if (isFav)
        {
          grpCapsules.members[realShit].favIcon.visible = true;
          grpCapsules.members[realShit].favIconBlurred.visible = true;
          grpCapsules.members[realShit].favIcon.animation.play('fav');
          grpCapsules.members[realShit].favIconBlurred.animation.play('fav');
          FunkinSound.playOnce(Paths.sound('fav'), 1);
          grpCapsules.members[realShit].checkClip();
          grpCapsules.members[realShit].selected = grpCapsules.members[realShit].selected; // set selected again, so it can run it's getter function to initialize movement
          busy = true;

          grpCapsules.members[realShit].doLerp = false;
          FlxTween.tween(grpCapsules.members[realShit], {y: grpCapsules.members[realShit].y - 5}, 0.1, {ease: FlxEase.expoOut});

          FlxTween.tween(grpCapsules.members[realShit], {y: grpCapsules.members[realShit].y + 5}, 0.1,
            {
              ease: FlxEase.expoIn,
              startDelay: 0.1,
              onComplete: function(_) {
                grpCapsules.members[realShit].doLerp = true;
                busy = false;
              }
            });
        }
        else
        {
          grpCapsules.members[realShit].favIcon.animation.play('fav', true, true, 9);
          grpCapsules.members[realShit].favIconBlurred.animation.play('fav', true, true, 9);
          FunkinSound.playOnce(Paths.sound('unfav'), 1);
          new FlxTimer().start(0.2, _ -> {
            grpCapsules.members[realShit].favIcon.visible = false;
            grpCapsules.members[realShit].favIconBlurred.visible = false;
            grpCapsules.members[realShit].checkClip();
          });

          busy = true;
          grpCapsules.members[realShit].doLerp = false;
          FlxTween.tween(grpCapsules.members[realShit], {y: grpCapsules.members[realShit].y + 5}, 0.1, {ease: FlxEase.expoOut});

          FlxTween.tween(grpCapsules.members[realShit], {y: grpCapsules.members[realShit].y - 5}, 0.1,
            {
              ease: FlxEase.expoIn,
              startDelay: 0.1,
              onComplete: function(_) {
                grpCapsules.members[realShit].doLerp = true;
                busy = false;
              }
            });
        }
      }
    }

    lerpScore = MathUtil.smoothLerp(lerpScore, intendedScore, elapsed, 0.5);
    lerpCompletion = MathUtil.smoothLerp(lerpCompletion, intendedCompletion, elapsed, 0.5);

    if (Math.isNaN(lerpScore))
    {
      lerpScore = intendedScore;
    }

    if (Math.isNaN(lerpCompletion))
    {
      lerpCompletion = intendedCompletion;
    }

    fp.updateScore(Std.int(lerpScore));

    txtCompletion.text = '${Math.floor(lerpCompletion * 100)}';

    // Right align the completion percentage
    switch (txtCompletion.text.length)
    {
      case 3:
        txtCompletion.offset.x = 10;
      case 2:
        txtCompletion.offset.x = 0;
      case 1:
        txtCompletion.offset.x = -24;
      default:
        txtCompletion.offset.x = 0;
    }

    handleInputs(elapsed);

    if (dj != null) FlxG.watch.addQuick('dj-anim', dj.getCurrentAnimation());
  }

  function handleInputs(elapsed:Float):Void
  {
    if (busy) return;

    var upP:Bool = controls.UI_UP_P;
    var downP:Bool = controls.UI_DOWN_P;
    var accepted:Bool = controls.ACCEPT;

    if (FlxG.onMobile)
    {
      for (touch in FlxG.touches.list)
      {
        if (touch.justPressed)
        {
          initTouchPos.set(touch.screenX, touch.screenY);
        }
        if (touch.pressed)
        {
          var dx:Float = initTouchPos.x - touch.screenX;
          var dy:Float = initTouchPos.y - touch.screenY;

          var angle:Float = Math.atan2(dy, dx);
          var length:Float = Math.sqrt(dx * dx + dy * dy);

          FlxG.watch.addQuick('LENGTH', length);
          FlxG.watch.addQuick('ANGLE', Math.round(FlxAngle.asDegrees(angle)));
        }
      }

      if (FlxG.touches.getFirst() != null)
      {
        if (touchTimer >= 1.5) accepted = true;

        touchTimer += elapsed;
        var touch:FlxTouch = FlxG.touches.getFirst();

        velTouch = Math.abs((touch.screenY - dyTouch)) / 50;

        dyTouch = touch.screenY - touchY;
        dxTouch = touch.screenX - touchX;

        if (touch.justPressed)
        {
          touchY = touch.screenY;
          dyTouch = 0;
          velTouch = 0;

          touchX = touch.screenX;
          dxTouch = 0;
        }

        if (Math.abs(dxTouch) >= 100)
        {
          touchX = touch.screenX;
          if (dxTouch != 0) dxTouch < 0 ? changeDiff(1) : changeDiff(-1);
        }

        if (Math.abs(dyTouch) >= 100)
        {
          touchY = touch.screenY;

          if (dyTouch != 0) dyTouch < 0 ? changeSelection(1) : changeSelection(-1);
        }
      }
      else
      {
        touchTimer = 0;
      }
    }

    #if mobile
    for (touch in FlxG.touches.list)
    {
      if (touch.justPressed)
      {
        // accepted = true;
      }
    }
    #end

    if ((controls.UI_UP || controls.UI_DOWN))
    {
      if (spamming)
      {
        if (spamTimer >= 0.07)
        {
          spamTimer = 0;

          if (controls.UI_UP)
          {
            changeSelection(-1);
          }
          else
          {
            changeSelection(1);
          }
        }
      }
      else if (spamTimer >= 0.9)
      {
        spamming = true;
      }
      else if (spamTimer <= 0)
      {
        if (controls.UI_UP)
        {
          changeSelection(-1);
        }
        else
        {
          changeSelection(1);
        }
      }

      spamTimer += elapsed;
      if (dj != null) dj.resetAFKTimer();
    }
    else
    {
      spamming = false;
      spamTimer = 0;
    }

    #if !html5
    if (FlxG.mouse.wheel != 0)
    {
      if (dj != null) dj.resetAFKTimer();
      changeSelection(-Math.round(FlxG.mouse.wheel));
    }
    #else
    if (FlxG.mouse.wheel < 0)
    {
      if (dj != null) dj.resetAFKTimer();
      changeSelection(-Math.round(FlxG.mouse.wheel / 8));
    }
    else if (FlxG.mouse.wheel > 0)
    {
      if (dj != null) dj.resetAFKTimer();
      changeSelection(-Math.round(FlxG.mouse.wheel / 8));
    }
    #end

    if (controls.UI_LEFT_P)
    {
      if (dj != null) dj.resetAFKTimer();
      changeDiff(-1);
      generateSongList(currentFilter, true);
    }
    if (controls.UI_RIGHT_P)
    {
      if (dj != null) dj.resetAFKTimer();
      changeDiff(1);
      generateSongList(currentFilter, true);
    }

    if (controls.BACK && !busy)
    {
      busy = true;
      FlxTween.globalManager.clear();
      FlxTimer.globalManager.clear();
      if (dj != null) dj.onIntroDone.removeAll();

      FunkinSound.playOnce(Paths.sound('cancelMenu'));

      var longestTimer:Float = 0;

      // FlxTween.color(bgDad, 0.33, 0xFFFFFFFF, 0xFF555555, {ease: FlxEase.quadOut});
      FlxTween.color(pinkBack, 0.25, 0xFFFFD863, 0xFFFFD0D5, {ease: FlxEase.quadOut});

      cardGlow.visible = true;
      cardGlow.alpha = 1;
      cardGlow.scale.set(1, 1);
      FlxTween.tween(cardGlow, {alpha: 0, "scale.x": 1.2, "scale.y": 1.2}, 0.25, {ease: FlxEase.sineOut});

      orangeBackShit.visible = false;
      alsoOrangeLOL.visible = false;

      moreWays.visible = false;
      funnyScroll.visible = false;
      txtNuts.visible = false;
      funnyScroll2.visible = false;
      moreWays2.visible = false;
      funnyScroll3.visible = false;

      for (grpSpr in exitMovers.keys())
      {
        var moveData:Null<MoveData> = exitMovers.get(grpSpr);
        if (moveData == null) continue;

        for (spr in grpSpr)
        {
          if (spr == null) continue;

          var funnyMoveShit:MoveData = moveData;

          var moveDataX = funnyMoveShit.x ?? spr.x;
          var moveDataY = funnyMoveShit.y ?? spr.y;
          var moveDataSpeed = funnyMoveShit.speed ?? 0.2;
          var moveDataWait = funnyMoveShit.wait ?? 0.0;

          FlxTween.tween(spr, {x: moveDataX, y: moveDataY}, moveDataSpeed, {ease: FlxEase.expoIn});

          longestTimer = Math.max(longestTimer, moveDataSpeed + moveDataWait);
        }
      }

      for (caps in grpCapsules.members)
      {
        caps.doJumpIn = false;
        caps.doLerp = false;
        caps.doJumpOut = true;
      }

      if (Type.getClass(_parentState) == MainMenuState)
      {
        _parentState.persistentUpdate = false;
        _parentState.persistentDraw = true;
      }

      new FlxTimer().start(longestTimer, (_) -> {
        FlxTransitionableState.skipNextTransIn = true;
        FlxTransitionableState.skipNextTransOut = true;
        if (Type.getClass(_parentState) == MainMenuState)
        {
          FunkinSound.playMusic('freakyMenu',
            {
              overrideExisting: true,
              restartTrack: false
            });
          FlxG.sound.music.fadeIn(4.0, 0.0, 1.0);
          close();
        }
        else
        {
          FlxG.switchState(() -> new MainMenuState());
        }
      });
    }

    if (accepted)
    {
      grpCapsules.members[curSelected].onConfirm();
    }
  }

  public override function destroy():Void
  {
    super.destroy();
    var daSong:Null<FreeplaySongData> = currentFilteredSongs[curSelected];
    if (daSong != null)
    {
      clearDaCache(daSong.songName);
    }
    // remove and destroy freeplay camera
    FlxG.cameras.remove(funnyCam);
  }

  function changeDiff(change:Int = 0, force:Bool = false):Void
  {
    touchTimer = 0;

    var currentDifficultyIndex:Int = diffIdsCurrent.indexOf(currentDifficulty);

    if (currentDifficultyIndex == -1) currentDifficultyIndex = diffIdsCurrent.indexOf(Constants.DEFAULT_DIFFICULTY);

    currentDifficultyIndex += change;

    if (currentDifficultyIndex < 0) currentDifficultyIndex = diffIdsCurrent.length - 1;
    if (currentDifficultyIndex >= diffIdsCurrent.length) currentDifficultyIndex = 0;

    currentDifficulty = diffIdsCurrent[currentDifficultyIndex];

    var daSong:Null<FreeplaySongData> = grpCapsules.members[curSelected].songData;
    if (daSong != null)
    {
      var targetSong:Null<Song> = SongRegistry.instance.fetchEntry(daSong.songId);
      if (targetSong == null)
      {
        FlxG.log.warn('WARN: could not find song with id (${daSong.songId})');
        return;
      }
      var targetVariation:String = targetSong.getFirstValidVariation(currentDifficulty) ?? '';

      // TODO: This line of code makes me sad, but you can't really fix it without a breaking migration.
      var suffixedDifficulty = (targetVariation != Constants.DEFAULT_VARIATION
        && targetVariation != 'erect') ? '$currentDifficulty-${targetVariation}' : currentDifficulty;
      var songScore:Null<SaveScoreData> = Save.instance.getSongScore(daSong.songId, suffixedDifficulty);
      intendedScore = songScore?.score ?? 0;
      intendedCompletion = songScore == null ? 0.0 : ((songScore.tallies.sick + songScore.tallies.good) / songScore.tallies.totalNotes);
      rememberedDifficulty = currentDifficulty;
    }
    else
    {
      intendedScore = 0;
      intendedCompletion = 0.0;
    }

    if (intendedCompletion == Math.POSITIVE_INFINITY || intendedCompletion == Math.NEGATIVE_INFINITY || Math.isNaN(intendedCompletion))
    {
      intendedCompletion = 0;
    }

    grpDifficulties.group.forEach(function(diffSprite) {
      diffSprite.visible = false;
    });

    for (diffSprite in grpDifficulties.group.members)
    {
      if (diffSprite == null) continue;
      if (diffSprite.difficultyId == currentDifficulty)
      {
        if (change != 0)
        {
          diffSprite.visible = true;
          diffSprite.offset.y += 5;
          diffSprite.alpha = 0.5;
          new FlxTimer().start(1 / 24, function(swag) {
            diffSprite.alpha = 1;
            diffSprite.updateHitbox();
          });
        }
        else
        {
          diffSprite.visible = true;
        }
      }
    }

    if (change != 0 || force)
    {
      // Update the song capsules to reflect the new difficulty info.
      for (songCapsule in grpCapsules.members)
      {
        if (songCapsule == null) continue;
        if (songCapsule.songData != null)
        {
          songCapsule.songData.currentDifficulty = currentDifficulty;
          songCapsule.init(null, null, songCapsule.songData);
          songCapsule.checkClip();
        }
        else
        {
          songCapsule.init(null, null, null);
        }
      }

      // Reset the song preview in case we changed variations (normal->erect etc)
      playCurSongPreview();
    }

    // Set the album graphic and play the animation if relevant.
    var newAlbumId:Null<String> = daSong?.albumId;
    if (albumRoll.albumId != newAlbumId)
    {
      albumRoll.albumId = newAlbumId;
      albumRoll.skipIntro();
    }

    // Set difficulty star count.
    albumRoll.setDifficultyStars(daSong?.difficultyRating);
  }

  // Clears the cache of songs, frees up memory, they' ll have to be loaded in later tho function clearDaCache(actualSongTho:String)
  function clearDaCache(actualSongTho:String):Void
  {
    for (song in songs)
    {
      if (song == null) continue;
      if (song.songName != actualSongTho)
      {
        trace('trying to remove: ' + song.songName);
        // openfl.Assets.cache.clear(Paths.inst(song.songName));
      }
    }
  }

  function capsuleOnConfirmRandom(randomCapsule:SongMenuItem):Void
  {
    trace('RANDOM SELECTED');

    busy = true;
    letterSort.inputEnabled = false;

    var availableSongCapsules:Array<SongMenuItem> = grpCapsules.members.filter(function(cap:SongMenuItem) {
      // Dead capsules are ones which were removed from the list when changing filters.
      return cap.alive && cap.songData != null;
    });

    trace('Available songs: ${availableSongCapsules.map(function(cap) {
      return cap?.songData?.songName;
    })}');

    if (availableSongCapsules.length == 0)
    {
      trace('No songs available!');
      busy = false;
      letterSort.inputEnabled = true;
      FunkinSound.playOnce(Paths.sound('cancelMenu'));
      return;
    }

    var targetSong:SongMenuItem = FlxG.random.getObject(availableSongCapsules);

    // Seeing if I can do an animation...
    curSelected = grpCapsules.members.indexOf(targetSong);
    changeSelection(0); // Trigger an update.

    // Act like we hit Confirm on that song.
    capsuleOnConfirmDefault(targetSong);
  }

  function capsuleOnConfirmDefault(cap:SongMenuItem):Void
  {
    busy = true;
    letterSort.inputEnabled = false;

    PlayStatePlaylist.isStoryMode = false;

    var targetSongId:String = cap?.songData?.songId ?? 'unknown';
    var targetSongNullable:Null<Song> = SongRegistry.instance.fetchEntry(targetSongId);
    if (targetSongNullable == null)
    {
      FlxG.log.warn('WARN: could not find song with id (${targetSongId})');
      return;
    }
    var targetSong:Song = targetSongNullable;
    var targetDifficultyId:String = currentDifficulty;
    var targetVariation:Null<String> = targetSong.getFirstValidVariation(targetDifficultyId, currentCharacter);
    var targetLevelId:Null<String> = cap?.songData?.levelId;
    PlayStatePlaylist.campaignId = targetLevelId ?? null;

    var targetDifficulty:Null<SongDifficulty> = targetSong.getDifficulty(targetDifficultyId, targetVariation);
    if (targetDifficulty == null)
    {
      FlxG.log.warn('WARN: could not find difficulty with id (${targetDifficultyId})');
      return;
    }

    var baseInstrumentalId:String = targetDifficulty?.characters?.instrumental ?? '';
    var altInstrumentalIds:Array<String> = targetDifficulty?.characters?.altInstrumentals ?? [];

    var targetInstId:String = baseInstrumentalId;

    // TODO: Make this a UI element.
    #if FEATURE_DEBUG_FUNCTIONS
    if (altInstrumentalIds.length > 0 && FlxG.keys.pressed.CONTROL)
    {
      targetInstId = altInstrumentalIds[0];
    }
    #end

    // Visual and audio effects.
    FunkinSound.playOnce(Paths.sound('confirmMenu'));
    if (dj != null) dj.confirm();

    grpCapsules.members[curSelected].forcePosition();
    grpCapsules.members[curSelected].confirm();

    // FlxTween.color(bgDad, 0.33, 0xFFFFFFFF, 0xFF555555, {ease: FlxEase.quadOut});
    FlxTween.color(pinkBack, 0.33, 0xFFFFD0D5, 0xFF171831, {ease: FlxEase.quadOut});
    orangeBackShit.visible = false;
    alsoOrangeLOL.visible = false;

    confirmGlow.visible = true;
    confirmGlow2.visible = true;

    backingTextYeah.playAnimation("BF back card confirm raw", false, false, false, 0);
    confirmGlow2.alpha = 0;
    confirmGlow.alpha = 0;

    FlxTween.tween(confirmGlow2, {alpha: 0.5}, 0.33,
      {
        ease: FlxEase.quadOut,
        onComplete: function(_) {
          confirmGlow2.alpha = 0.6;
          confirmGlow.alpha = 1;
          confirmTextGlow.visible = true;
          confirmTextGlow.alpha = 1;
          FlxTween.tween(confirmTextGlow, {alpha: 0.4}, 0.5);
          FlxTween.tween(confirmGlow, {alpha: 0}, 0.5);
        }
      });

    // confirmGlow

    moreWays.visible = false;
    funnyScroll.visible = false;
    txtNuts.visible = false;
    funnyScroll2.visible = false;
    moreWays2.visible = false;
    funnyScroll3.visible = false;

    new FlxTimer().start(1, function(tmr:FlxTimer) {
      FunkinSound.emptyPartialQueue();

      Paths.setCurrentLevel(cap?.songData?.levelId);
      LoadingState.loadPlayState(
        {
          targetSong: targetSong,
          targetDifficulty: targetDifficultyId,
          targetVariation: targetVariation,
          targetInstrumental: targetInstId,
          practiceMode: false,
          minimalMode: false,

          #if FEATURE_DEBUG_FUNCTIONS
          botPlayMode: FlxG.keys.pressed.SHIFT,
          #else
          botPlayMode: false,
          #end
          // TODO: Make these an option! It's currently only accessible via chart editor.
          // startTimestamp: 0.0,
          // playbackRate: 0.5,
          // botPlayMode: true,
        }, true);
    });
  }

  function rememberSelection():Void
  {
    if (rememberedSongId != null)
    {
      curSelected = currentFilteredSongs.findIndex(function(song) {
        if (song == null) return false;
        return song.songId == rememberedSongId;
      });

      if (curSelected == -1) curSelected = 0;
    }

    if (rememberedDifficulty != null)
    {
      currentDifficulty = rememberedDifficulty;
    }
  }

  function changeSelection(change:Int = 0):Void
  {
    var prevSelected:Int = curSelected;

    curSelected += change;

    if (!prepForNewRank && curSelected != prevSelected) FunkinSound.playOnce(Paths.sound('scrollMenu'), 0.4);

    if (curSelected < 0) curSelected = grpCapsules.countLiving() - 1;
    if (curSelected >= grpCapsules.countLiving()) curSelected = 0;

    var daSongCapsule:SongMenuItem = grpCapsules.members[curSelected];
    if (daSongCapsule.songData != null)
    {
      var songScore:Null<SaveScoreData> = Save.instance.getSongScore(daSongCapsule.songData.songId, currentDifficulty);
      intendedScore = songScore?.score ?? 0;
      intendedCompletion = songScore == null ? 0.0 : ((songScore.tallies.sick + songScore.tallies.good) / songScore.tallies.totalNotes);
      diffIdsCurrent = daSongCapsule.songData.songDifficulties;
      rememberedSongId = daSongCapsule.songData.songId;
      changeDiff();
    }
    else
    {
      intendedScore = 0;
      intendedCompletion = 0.0;
      diffIdsCurrent = diffIdsTotal;
      rememberedSongId = null;
      rememberedDifficulty = Constants.DEFAULT_DIFFICULTY;
      albumRoll.albumId = null;
    }

    for (index => capsule in grpCapsules.members)
    {
      index += 1;

      capsule.selected = index == curSelected + 1;

      capsule.targetPos.y = capsule.intendedY(index - curSelected);
      capsule.targetPos.x = 270 + (60 * (Math.sin(index - curSelected)));

      if (index < curSelected) capsule.targetPos.y -= 100; // another 100 for good measure
    }

    if (grpCapsules.countLiving() > 0 && !prepForNewRank)
    {
      playCurSongPreview(daSongCapsule);
      grpCapsules.members[curSelected].selected = true;
    }
  }

  public function playCurSongPreview(?daSongCapsule:SongMenuItem):Void
  {
    if (daSongCapsule == null) daSongCapsule = grpCapsules.members[curSelected];

    if (curSelected == 0)
    {
      FunkinSound.playMusic('freeplayRandom',
        {
          startingVolume: 0.0,
          overrideExisting: true,
          restartTrack: false
        });
      FlxG.sound.music.fadeIn(2, 0, 0.8);
    }
    else
    {
      var previewSongId:Null<String> = daSongCapsule?.songData?.songId;
      if (previewSongId == null) return;

      var previewSong:Null<Song> = SongRegistry.instance.fetchEntry(previewSongId);
      var songDifficulty = previewSong?.getDifficulty(currentDifficulty,
        previewSong?.getVariationsByCharacter(currentCharacter) ?? Constants.DEFAULT_VARIATION_LIST);
      var baseInstrumentalId:String = songDifficulty?.characters?.instrumental ?? '';
      var altInstrumentalIds:Array<String> = songDifficulty?.characters?.altInstrumentals ?? [];

      var instSuffix:String = baseInstrumentalId;

      // TODO: Make this a UI element.
      #if FEATURE_DEBUG_FUNCTIONS
      if (altInstrumentalIds.length > 0 && FlxG.keys.pressed.CONTROL)
      {
        instSuffix = altInstrumentalIds[0];
      }
      #end

      instSuffix = (instSuffix != '') ? '-$instSuffix' : '';

      trace('Attempting to play partial preview: ${previewSongId}:${instSuffix}');

      FunkinSound.playMusic(previewSongId,
        {
          startingVolume: 0.0,
          overrideExisting: true,
          restartTrack: false,
          mapTimeChanges: false, // The music metadata is not alongside the audio file so this won't work.
          pathsFunction: INST,
          suffix: instSuffix,
          partialParams:
            {
              loadPartial: true,
              start: 0.05,
              end: 0.25
            },
          onLoad: function() {
            FlxG.sound.music.fadeIn(2, 0, 0.4);
          }
        });
    }
  }

  /**
   * Build an instance of `FreeplayState` that is above the `MainMenuState`.
   * @return The MainMenuState with the FreeplayState as a substate.
   */
  public static function build(?params:FreeplayStateParams, ?stickers:StickerSubState):MusicBeatState
  {
    var result:MainMenuState;
    if (params?.fromResults?.playRankAnim ?? false) result = new MainMenuState(true);
    else
      result = new MainMenuState(false);

    result.openSubState(new FreeplayState(params, stickers));
    result.persistentUpdate = false;
    result.persistentDraw = true;
    return result;
  }
}

/**
 * The difficulty selector arrows to the left and right of the difficulty.
 */
class DifficultySelector extends FlxSprite
{
  var controls:Controls;
  var whiteShader:PureColor;

  var parent:FreeplayState;

  public function new(parent:FreeplayState, x:Float, y:Float, flipped:Bool, controls:Controls)
  {
    super(x, y);

    this.parent = parent;
    this.controls = controls;

    frames = Paths.getSparrowAtlas('freeplay/freeplaySelector');
    animation.addByPrefix('shine', 'arrow pointer loop', 24);
    animation.play('shine');

    whiteShader = new PureColor(FlxColor.WHITE);

    shader = whiteShader;

    flipX = flipped;
  }

  override function update(elapsed:Float):Void
  {
    if (flipX && controls.UI_RIGHT_P && !parent.busy) moveShitDown();
    if (!flipX && controls.UI_LEFT_P && !parent.busy) moveShitDown();

    super.update(elapsed);
  }

  function moveShitDown():Void
  {
    offset.y -= 5;

    whiteShader.colorSet = true;

    scale.x = scale.y = 0.5;

    new FlxTimer().start(2 / 24, function(tmr) {
      scale.x = scale.y = 1;
      whiteShader.colorSet = false;
      updateHitbox();
    });
  }
}

/**
 * Structure for the current song filter.
 */
typedef SongFilter =
{
  var filterType:FilterType;
  var ?filterData:Dynamic;
}

/**
 * Possible types to use for the song filter.
 */
enum abstract FilterType(String)
{
  /**
   * Filter to songs which start with a string
   */
  public var STARTSWITH;

  /**
   * Filter to songs which match a regular expression
   */
  public var REGEXP;

  /**
   * Filter to songs which are favorited
   */
  public var FAVORITE;

  /**
   * Filter to all songs
   */
  public var ALL;
}

/**
 * Data about a specific song in the freeplay menu.
 */
class FreeplaySongData
{
  /**
   * Whether or not the song has been favorited.
   */
  public var isFav:Bool = false;

  public var isNew:Bool = false;

  var song:Song;

  public var levelId(default, null):String = '';
  public var songId(default, null):String = '';

  public var songDifficulties(default, null):Array<String> = [];

  public var songName(default, null):String = '';
  public var songCharacter(default, null):String = '';
  public var songStartingBpm(default, null):Float = 0;
  public var difficultyRating(default, null):Int = 0;
  public var albumId(default, null):Null<String> = null;

  public var currentDifficulty(default, set):String = Constants.DEFAULT_DIFFICULTY;

  public var scoringRank:Null<ScoringRank> = null;

  var displayedVariations:Array<String> = [Constants.DEFAULT_VARIATION];

  function set_currentDifficulty(value:String):String
  {
    if (currentDifficulty == value) return value;

    currentDifficulty = value;
    updateValues(displayedVariations);
    return value;
  }

  public function new(levelId:String, songId:String, song:Song, ?displayedVariations:Array<String>)
  {
    this.levelId = levelId;
    this.songId = songId;
    this.song = song;

    this.isFav = Save.instance.isSongFavorited(songId);

    if (displayedVariations != null) this.displayedVariations = displayedVariations;

    updateValues(displayedVariations);
  }

  /**
   * Toggle whether or not the song is favorited, then flush to save data.
   * @return Whether or not the song is now favorited.
   */
  public function toggleFavorite():Bool
  {
    isFav = !isFav;
    if (isFav)
    {
      Save.instance.favoriteSong(this.songId);
    }
    else
    {
      Save.instance.unfavoriteSong(this.songId);
    }
    return isFav;
  }

  function updateValues(variations:Array<String>):Void
  {
    this.songDifficulties = song.listDifficulties(null, variations, false, false);
    if (!this.songDifficulties.contains(currentDifficulty))
    {
      currentDifficulty = Constants.DEFAULT_DIFFICULTY;
      // This method gets called again by the setter-method
      // or the difficulty didn't change, so there's no need to continue.
      return;
    }

    var songDifficulty:SongDifficulty = song.getDifficulty(currentDifficulty, null, variations);
    if (songDifficulty == null) return;
    this.songStartingBpm = songDifficulty.getStartingBPM();
    this.songName = songDifficulty.songName;
    this.songCharacter = songDifficulty.characters.opponent;
    this.difficultyRating = songDifficulty.difficultyRating;
    if (songDifficulty.album == null)
    {
      FlxG.log.warn('No album for: ${songDifficulty.songName}');
      this.albumId = Constants.DEFAULT_ALBUM_ID;
    }
    else
    {
      this.albumId = songDifficulty.album;
    }

    // TODO: This line of code makes me sad, but you can't really fix it without a breaking migration.
    // `easy`, `erect`, `normal-pico`, etc.
    var suffixedDifficulty = (songDifficulty.variation != Constants.DEFAULT_VARIATION
      && songDifficulty.variation != 'erect') ? '$currentDifficulty-${songDifficulty.variation}' : currentDifficulty;

    this.scoringRank = Save.instance.getSongRank(songId, suffixedDifficulty);

    this.isNew = song.isSongNew(currentDifficulty);
  }
}

/**
 * The map storing information about the exit movers.
 */
typedef ExitMoverData = Map<Array<FlxSprite>, MoveData>;

/**
 * The data for an exit mover.
 */
typedef MoveData =
{
  var ?x:Float;
  var ?y:Float;
  var ?speed:Float;
  var ?wait:Float;
}

/**
 * The sprite for the difficulty
 */
class DifficultySprite extends FlxSprite
{
  /**
   * The difficulty id which this sprite represents.
   */
  public var difficultyId:String;

  public function new(diffId:String)
  {
    super();

    difficultyId = diffId;

    var assetDiffId:String = diffId;
    while (!Assets.exists(Paths.image('freeplay/freeplay${assetDiffId}')))
    {
      // Remove the last suffix of the difficulty id until we find an asset or there are no more suffixes.
      var assetDiffIdParts:Array<String> = assetDiffId.split('-');
      assetDiffIdParts.pop();
      if (assetDiffIdParts.length == 0) break;
      assetDiffId = assetDiffIdParts.join('-');
    }

    // Check for an XML to use an animation instead of an image.
    if (Assets.exists(Paths.file('images/freeplay/freeplay${assetDiffId}.xml')))
    {
      this.frames = Paths.getSparrowAtlas('freeplay/freeplay${assetDiffId}');
      this.animation.addByPrefix('idle', 'idle0', 24, true);
      if (Preferences.flashingLights) this.animation.play('idle');
    }
    else
    {
      this.loadGraphic(Paths.image('freeplay/freeplay' + assetDiffId));
    }
  }
}