Old .osu file formats need to be parsed differently

[OsuManiaMan]

Osu has used osu format v14 for some time now but older maps exist with previous formats. The issue I have found is that long notes were not represented the same in older versions. Format v10 represents long notes like this: 256,354,164149,2,0,B|256:208,1,140 for example. Strangely, no end time is specified. Here is an example of a map with v10 format: Identity Part II. Format v12 on the other hand looks something like this: 36,192,45367,128,0,45700:0:0:0:0:. End time is provided but the issue with this version is that normal notes look like this: 182,352,45367,1,0,1:0:0:0:. Where the end time would be, there is instead a number representing what I believe is the sampleset, in this case 1 for Normal I think. The issue with this is that a note with timestamp 0 and a value greater than 0 in that position will be seen as a long note with the current code.

ShaRk/utils/parser.py

Line 21 in 8586965

self.isln = lnend > timestamp

Here is an example of a map with v12 formatting: ChaiN De/structioN

[OsuManiaMan]

After some more messing around with .osu files, I found out that you can mix and match formats and osu just figures it out. The Chain Destruction [Another] example above contains a v10 style line 475,352,142700,2,0,L|475:288,24,63 (this is the only one like it in the file). This same line can even be inserted into modern maps with no issue. I believe osu just keeps trying to parse the line with different formats until something succeeds. All that said, it means we can't even trust the first line of the .osu file which specifies the format. Isn't that just wonderful.