Add ability to sort save files by name or date

[usidedown]

Solves #1211

Introduces a new configuration save file sorting that changes the way sorting works in the load dialog

✅ Allows sorting by timestamp rather than filename
✅ Doesn't change the default behavior
❌No UI improvements
✅ Awesome UI thanks to @zenseii

[ihhub]

Hi @usidedown , without UI changes most of players would never even know about this feature. We have to provide a user-friendly solution and do not rely on the configuration file which is served only for developers.

This is a UX design of how we can implement sorting mechanism (provided by @OogaBoogaCode in Discord - https://discord.com/channels/733093692860137523/963076826673070130/1338909387158454445):

The initial PR was here: #9560 but I don't know why the author removed everything.

To change UI you can start looking at dialog_selectfile.cpp file, selectFileListSimple() function. You will need to add a button with "SORT" title. Please let me know if you have any questions.

[usidedown]

@ihhub UI part is done, let me know how it looks.

I'm slightly worried about the performance of clicking the sort button. Not sure if it's worth improving though.

There are 2 "heavy" operations:

• the sorting itself should be NLOGN comparisons, but each comparison is not very cheap when comparing filenames. Fixing this is probably a bigger change and probably deserves its own PR.
• I also need to find the last selected item and re-selected in the new list. This is again N comparisons of file names. Maybe it's possible to compare pointers instead of strings to speed things up. Not sure it's worth doing.

What do you think?

[ihhub]

Hi @usidedown , don't worry about sorting or search as we are handling at max < 1000 items so this operation is heavy in theory, in reality rendering would be much longer. If we avoid any I/O operations while changing sorting then it doesn't impact the performance too much.

And as usual we can always improve performance later.

[ihhub]

@usidedown , could you please also resolve merge conflicts to proceed with the review?

[usidedown]

@usidedown , could you please also resolve merge conflicts to proceed with the review?

@ihhub Is the proposed UI design acceptable? I got the impression from discord that we want something different.

[ihhub]

Hi @usidedown , I put several comments in this pull request. Could you please take a look at them in your free time?

[ihhub]

Hi @usidedown , I added few more comments here. Would you mind to take a look at them?

[ihhub]

Hi @usidedown , I added 2 more comments here. Would you mind to take a look at them?

[usidedown]

@ihhub thanks for the review
I'll take a look after the weekend.
Might revert the last commit if I can't simplify.

[usidedown]

@zenseii your design definitely looks better!
Is it a big change (code-wise) w.r.t the current PR?
I barely managed to put a button, not sure if I can handle this design 😅

[zenseii]

@zenseii your design definitely looks better! Is it a big change (code-wise) w.r.t the current PR? I barely managed to put a button, not sure if I can handle this design 😅

Thanks! I can push the needed changes as I did some of them already for the screenshot (it was less work than photoshopping it). I'll expand the height of the header cells too.

[oleg-derevenetz]

Hi @usidedown I just made a few changes:

• Renamed the Settings::changeSaveFileSortingMethod() to the Settings::toggleSaveFileSortingMethod() - it seems to me that this variant reflects its essence better.

• Moved the CaseInsensitiveCompare() to the tools.h (as fheroes2::compareStringsCaseInsensitively()) since this function is "relatively generic" and can be used in multiple places... But for now it is used just in maps_fileinfo.cpp.

• Moved all comparators to the single place so that there will be no confusion if there is a need to change something.

• Fixed the issue like this:

  fheroes2.engine.version_.1.1.8.2025-06-07.22-48-18.mp4

  std::lower_bound() doesn't mean "equality" per se.

• Fixed the similar issue on the case-sensitive filesystems. Given that the current sorting is case-insensitive, there can be multiple "identical" file names with different case.

• Added a few assertions (for the debug builds only) to check that lists are properly sorted/partitioned before calling std::lower_bound() or std::equal_range() on them. Attempting to call these functions on an incorrectly sorted list causes undefined behavior.

Could you please take a look at these changes to make sure I didn't miss anything?

[usidedown]

@oleg-derevenetz thank you so much for these fixes!

Code looks correct overall, but I have minor suggestions.

[github-actions]

⚠️ Clang-Tidy found issue(s) with the introduced code (1/1)

[zenseii]

Hi, @usidedown. I've added the header cells and radio buttons. Things are a bit more crammed in the dialog now. Ideally the way the size of the dialog is setup according to resolution and number of save files should be reworked, but for now I think this is good enough.

[Districh-ru]

Hi @usidedown, I left several comments. Could you please take a look when you have time?

[Districh-ru]

Well done, @usidedown.

You can also mark in the PR topic that there are UI improvements. :)

[ihhub]

@usidedown , many thanks for this feature!