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osu-lazer/osu.Game/Beatmaps/Formats/LegacyBeatmapDecoder.cs
Bartłomiej Dach 86588778b1 Implement fallback decoder registration
After the preparatory introduction of LineBufferedReader, it is now
possible to introduce registration of fallback decoders that won't drop
input supplied in the first line of the file.

A fallback decoder is used when the magic in the first line of the file
does not match any of the other known decoders. In such a case,
the fallback decoder is constructed and provided a LineBufferedReader
instance. The process of matching magic only peeks the first non-empty
line, so it is available for re-reading in Decode() using ReadLine().

There can be only one fallback decoder per type; a second attempt of
registering a fallback will result in an exception to avoid bugs.

To address the issue of parsing failing on badly or non-headered files,
set the legacy decoders for Beatmaps and Storyboards as the fallbacks.

Due to non-trivial logic, several new, passing unit tests with possible
edge cases also included.
2019-09-15 01:28:07 +02:00

500 lines
18 KiB
C#

// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
// See the LICENCE file in the repository root for full licence text.
using System;
using System.IO;
using System.Linq;
using osu.Framework.IO.File;
using osu.Game.Beatmaps.Timing;
using osu.Game.Rulesets.Objects.Legacy;
using osu.Game.Beatmaps.ControlPoints;
using osu.Game.IO;
namespace osu.Game.Beatmaps.Formats
{
public class LegacyBeatmapDecoder : LegacyDecoder<Beatmap>
{
public const int LATEST_VERSION = 14;
private Beatmap beatmap;
private ConvertHitObjectParser parser;
private LegacySampleBank defaultSampleBank;
private int defaultSampleVolume = 100;
public static void Register()
{
AddDecoder<Beatmap>(@"osu file format v", m => new LegacyBeatmapDecoder(Parsing.ParseInt(m.Split('v').Last())));
SetFallbackDecoder<Beatmap>(() => new LegacyBeatmapDecoder());
}
/// <summary>
/// Whether or not beatmap or runtime offsets should be applied. Defaults on; only disable for testing purposes.
/// </summary>
public bool ApplyOffsets = true;
private readonly int offset;
public LegacyBeatmapDecoder(int version = LATEST_VERSION)
: base(version)
{
// BeatmapVersion 4 and lower had an incorrect offset (stable has this set as 24ms off)
offset = FormatVersion < 5 ? 24 : 0;
}
protected override void ParseStreamInto(LineBufferedReader stream, Beatmap beatmap)
{
this.beatmap = beatmap;
this.beatmap.BeatmapInfo.BeatmapVersion = FormatVersion;
base.ParseStreamInto(stream, beatmap);
// Objects may be out of order *only* if a user has manually edited an .osu file.
// Unfortunately there are ranked maps in this state (example: https://osu.ppy.sh/s/594828).
// OrderBy is used to guarantee that the parsing order of hitobjects with equal start times is maintained (stably-sorted)
// The parsing order of hitobjects matters in mania difficulty calculation
this.beatmap.HitObjects = this.beatmap.HitObjects.OrderBy(h => h.StartTime).ToList();
foreach (var hitObject in this.beatmap.HitObjects)
hitObject.ApplyDefaults(this.beatmap.ControlPointInfo, this.beatmap.BeatmapInfo.BaseDifficulty);
}
protected override bool ShouldSkipLine(string line) => base.ShouldSkipLine(line) || line.StartsWith(" ", StringComparison.Ordinal) || line.StartsWith("_", StringComparison.Ordinal);
protected override void ParseLine(Beatmap beatmap, Section section, string line)
{
var strippedLine = StripComments(line);
switch (section)
{
case Section.General:
handleGeneral(strippedLine);
return;
case Section.Editor:
handleEditor(strippedLine);
return;
case Section.Metadata:
handleMetadata(line);
return;
case Section.Difficulty:
handleDifficulty(strippedLine);
return;
case Section.Events:
handleEvent(strippedLine);
return;
case Section.TimingPoints:
handleTimingPoint(strippedLine);
return;
case Section.HitObjects:
handleHitObject(strippedLine);
return;
}
base.ParseLine(beatmap, section, line);
}
private void handleGeneral(string line)
{
var pair = SplitKeyVal(line);
var metadata = beatmap.BeatmapInfo.Metadata;
switch (pair.Key)
{
case @"AudioFilename":
metadata.AudioFile = FileSafety.PathStandardise(pair.Value);
break;
case @"AudioLeadIn":
beatmap.BeatmapInfo.AudioLeadIn = Parsing.ParseInt(pair.Value);
break;
case @"PreviewTime":
metadata.PreviewTime = getOffsetTime(Parsing.ParseInt(pair.Value));
break;
case @"Countdown":
beatmap.BeatmapInfo.Countdown = Parsing.ParseInt(pair.Value) == 1;
break;
case @"SampleSet":
defaultSampleBank = (LegacySampleBank)Enum.Parse(typeof(LegacySampleBank), pair.Value);
break;
case @"SampleVolume":
defaultSampleVolume = Parsing.ParseInt(pair.Value);
break;
case @"StackLeniency":
beatmap.BeatmapInfo.StackLeniency = Parsing.ParseFloat(pair.Value);
break;
case @"Mode":
beatmap.BeatmapInfo.RulesetID = Parsing.ParseInt(pair.Value);
switch (beatmap.BeatmapInfo.RulesetID)
{
case 0:
parser = new Rulesets.Objects.Legacy.Osu.ConvertHitObjectParser(getOffsetTime(), FormatVersion);
break;
case 1:
parser = new Rulesets.Objects.Legacy.Taiko.ConvertHitObjectParser(getOffsetTime(), FormatVersion);
break;
case 2:
parser = new Rulesets.Objects.Legacy.Catch.ConvertHitObjectParser(getOffsetTime(), FormatVersion);
break;
case 3:
parser = new Rulesets.Objects.Legacy.Mania.ConvertHitObjectParser(getOffsetTime(), FormatVersion);
break;
}
break;
case @"LetterboxInBreaks":
beatmap.BeatmapInfo.LetterboxInBreaks = Parsing.ParseInt(pair.Value) == 1;
break;
case @"SpecialStyle":
beatmap.BeatmapInfo.SpecialStyle = Parsing.ParseInt(pair.Value) == 1;
break;
case @"WidescreenStoryboard":
beatmap.BeatmapInfo.WidescreenStoryboard = Parsing.ParseInt(pair.Value) == 1;
break;
}
}
private void handleEditor(string line)
{
var pair = SplitKeyVal(line);
switch (pair.Key)
{
case @"Bookmarks":
beatmap.BeatmapInfo.StoredBookmarks = pair.Value;
break;
case @"DistanceSpacing":
beatmap.BeatmapInfo.DistanceSpacing = Math.Max(0, Parsing.ParseDouble(pair.Value));
break;
case @"BeatDivisor":
beatmap.BeatmapInfo.BeatDivisor = Parsing.ParseInt(pair.Value);
break;
case @"GridSize":
beatmap.BeatmapInfo.GridSize = Parsing.ParseInt(pair.Value);
break;
case @"TimelineZoom":
beatmap.BeatmapInfo.TimelineZoom = Math.Max(0, Parsing.ParseDouble(pair.Value));
break;
}
}
private void handleMetadata(string line)
{
var pair = SplitKeyVal(line);
var metadata = beatmap.BeatmapInfo.Metadata;
switch (pair.Key)
{
case @"Title":
metadata.Title = pair.Value;
break;
case @"TitleUnicode":
metadata.TitleUnicode = pair.Value;
break;
case @"Artist":
metadata.Artist = pair.Value;
break;
case @"ArtistUnicode":
metadata.ArtistUnicode = pair.Value;
break;
case @"Creator":
metadata.AuthorString = pair.Value;
break;
case @"Version":
beatmap.BeatmapInfo.Version = pair.Value;
break;
case @"Source":
beatmap.BeatmapInfo.Metadata.Source = pair.Value;
break;
case @"Tags":
beatmap.BeatmapInfo.Metadata.Tags = pair.Value;
break;
case @"BeatmapID":
beatmap.BeatmapInfo.OnlineBeatmapID = Parsing.ParseInt(pair.Value);
break;
case @"BeatmapSetID":
beatmap.BeatmapInfo.BeatmapSet = new BeatmapSetInfo { OnlineBeatmapSetID = Parsing.ParseInt(pair.Value) };
break;
}
}
private void handleDifficulty(string line)
{
var pair = SplitKeyVal(line);
var difficulty = beatmap.BeatmapInfo.BaseDifficulty;
switch (pair.Key)
{
case @"HPDrainRate":
difficulty.DrainRate = Parsing.ParseFloat(pair.Value);
break;
case @"CircleSize":
difficulty.CircleSize = Parsing.ParseFloat(pair.Value);
break;
case @"OverallDifficulty":
difficulty.OverallDifficulty = Parsing.ParseFloat(pair.Value);
break;
case @"ApproachRate":
difficulty.ApproachRate = Parsing.ParseFloat(pair.Value);
break;
case @"SliderMultiplier":
difficulty.SliderMultiplier = Parsing.ParseDouble(pair.Value);
break;
case @"SliderTickRate":
difficulty.SliderTickRate = Parsing.ParseDouble(pair.Value);
break;
}
}
private void handleEvent(string line)
{
string[] split = line.Split(',');
EventType type;
if (!Enum.TryParse(split[0], out type))
throw new InvalidDataException($@"Unknown event type: {split[0]}");
switch (type)
{
case EventType.Background:
string bgFilename = split[2].Trim('"');
beatmap.BeatmapInfo.Metadata.BackgroundFile = FileSafety.PathStandardise(bgFilename);
break;
case EventType.Video:
string videoFilename = split[2].Trim('"');
beatmap.BeatmapInfo.Metadata.VideoFile = FileSafety.PathStandardise(videoFilename);
break;
case EventType.Break:
double start = getOffsetTime(Parsing.ParseDouble(split[1]));
var breakEvent = new BreakPeriod
{
StartTime = start,
EndTime = Math.Max(start, getOffsetTime(Parsing.ParseDouble(split[2])))
};
if (!breakEvent.HasEffect)
return;
beatmap.Breaks.Add(breakEvent);
break;
}
}
private void handleTimingPoint(string line)
{
string[] split = line.Split(',');
double time = getOffsetTime(Parsing.ParseDouble(split[0].Trim()));
double beatLength = Parsing.ParseDouble(split[1].Trim());
double speedMultiplier = beatLength < 0 ? 100.0 / -beatLength : 1;
TimeSignatures timeSignature = TimeSignatures.SimpleQuadruple;
if (split.Length >= 3)
timeSignature = split[2][0] == '0' ? TimeSignatures.SimpleQuadruple : (TimeSignatures)Parsing.ParseInt(split[2]);
LegacySampleBank sampleSet = defaultSampleBank;
if (split.Length >= 4)
sampleSet = (LegacySampleBank)Parsing.ParseInt(split[3]);
int customSampleBank = 0;
if (split.Length >= 5)
customSampleBank = Parsing.ParseInt(split[4]);
int sampleVolume = defaultSampleVolume;
if (split.Length >= 6)
sampleVolume = Parsing.ParseInt(split[5]);
bool timingChange = true;
if (split.Length >= 7)
timingChange = split[6][0] == '1';
bool kiaiMode = false;
bool omitFirstBarSignature = false;
if (split.Length >= 8)
{
EffectFlags effectFlags = (EffectFlags)Parsing.ParseInt(split[7]);
kiaiMode = effectFlags.HasFlag(EffectFlags.Kiai);
omitFirstBarSignature = effectFlags.HasFlag(EffectFlags.OmitFirstBarLine);
}
string stringSampleSet = sampleSet.ToString().ToLowerInvariant();
if (stringSampleSet == @"none")
stringSampleSet = @"normal";
if (timingChange)
{
var controlPoint = CreateTimingControlPoint();
controlPoint.Time = time;
controlPoint.BeatLength = beatLength;
controlPoint.TimeSignature = timeSignature;
handleTimingControlPoint(controlPoint);
}
handleDifficultyControlPoint(new DifficultyControlPoint
{
Time = time,
SpeedMultiplier = speedMultiplier,
AutoGenerated = timingChange
});
handleEffectControlPoint(new EffectControlPoint
{
Time = time,
KiaiMode = kiaiMode,
OmitFirstBarLine = omitFirstBarSignature,
AutoGenerated = timingChange
});
handleSampleControlPoint(new LegacySampleControlPoint
{
Time = time,
SampleBank = stringSampleSet,
SampleVolume = sampleVolume,
CustomSampleBank = customSampleBank,
AutoGenerated = timingChange
});
}
private void handleTimingControlPoint(TimingControlPoint newPoint)
{
var existing = beatmap.ControlPointInfo.TimingPointAt(newPoint.Time);
if (existing.Time == newPoint.Time)
{
// autogenerated points should not replace non-autogenerated.
// this allows for incorrectly ordered timing points to still be correctly handled.
if (newPoint.AutoGenerated && !existing.AutoGenerated)
return;
beatmap.ControlPointInfo.TimingPoints.Remove(existing);
}
beatmap.ControlPointInfo.TimingPoints.Add(newPoint);
}
private void handleDifficultyControlPoint(DifficultyControlPoint newPoint)
{
var existing = beatmap.ControlPointInfo.DifficultyPointAt(newPoint.Time);
if (existing.Time == newPoint.Time)
{
// autogenerated points should not replace non-autogenerated.
// this allows for incorrectly ordered timing points to still be correctly handled.
if (newPoint.AutoGenerated && !existing.AutoGenerated)
return;
beatmap.ControlPointInfo.DifficultyPoints.Remove(existing);
}
beatmap.ControlPointInfo.DifficultyPoints.Add(newPoint);
}
private void handleEffectControlPoint(EffectControlPoint newPoint)
{
var existing = beatmap.ControlPointInfo.EffectPointAt(newPoint.Time);
if (existing.Time == newPoint.Time)
{
// autogenerated points should not replace non-autogenerated.
// this allows for incorrectly ordered timing points to still be correctly handled.
if (newPoint.AutoGenerated && !existing.AutoGenerated)
return;
beatmap.ControlPointInfo.EffectPoints.Remove(existing);
}
beatmap.ControlPointInfo.EffectPoints.Add(newPoint);
}
private void handleSampleControlPoint(SampleControlPoint newPoint)
{
var existing = beatmap.ControlPointInfo.SamplePointAt(newPoint.Time);
if (existing.Time == newPoint.Time)
{
// autogenerated points should not replace non-autogenerated.
// this allows for incorrectly ordered timing points to still be correctly handled.
if (newPoint.AutoGenerated && !existing.AutoGenerated)
return;
beatmap.ControlPointInfo.SamplePoints.Remove(existing);
}
beatmap.ControlPointInfo.SamplePoints.Add(newPoint);
}
private void handleHitObject(string line)
{
// If the ruleset wasn't specified, assume the osu!standard ruleset.
if (parser == null)
parser = new Rulesets.Objects.Legacy.Osu.ConvertHitObjectParser(getOffsetTime(), FormatVersion);
var obj = parser.Parse(line);
if (obj != null)
beatmap.HitObjects.Add(obj);
}
private int getOffsetTime(int time) => time + (ApplyOffsets ? offset : 0);
private double getOffsetTime() => ApplyOffsets ? offset : 0;
private double getOffsetTime(double time) => time + (ApplyOffsets ? offset : 0);
protected virtual TimingControlPoint CreateTimingControlPoint() => new TimingControlPoint();
[Flags]
internal enum EffectFlags
{
None = 0,
Kiai = 1,
OmitFirstBarLine = 8
}
}
}