[Suggestion] Style guideline and code beautification

[Mayriad]

I am going to get fussy now, but this is of course not a real problem that needs to be fixed.

I have only read and worked on a tiny proportion of the code, but the existing coding style I have seen so far is very messy and made it difficult for me to comply. I will list some problems below; all examples are taken from EHentai.pm:

• Spaces inside brackets, which is uncommon and also not consistently applied:

if ( $gID eq "" ) {
...
if ($hashdata{tags} ne "") {

• Visual indentation, which cannot be consistently applied anyway:

my ( $title, $tags, $thumbhash, $defaultlanguage, $ua, $domain, $usethumbs) = @_;
my $logger = get_logger( "E-Hentai", "plugins" );
my $URL    = "";

• Inconsistent indentation:

    } else {
        # Craft URL for Text Search on EH if there's no user argument
        ( $gID, $gToken ) =
          &lookup_gallery( $lrr_info->{archive_title}, $lrr_info->{existing_tags}, 
                           $lrr_info->{thumbnail_hash}, $lang, $lrr_info->{user_agent}, $domain, $usethumbs);

• Inconsistent variable naming:

my $lrr_info = shift; # snake_case
my ($lang, $savetitle, $usethumbs, $enablepanda) = @_; # flatcase
...
my $gID    = ""; # camelCase

• Undescriptive variable names:

my $rep = $ua->post(

• Lack of code width limit e.g., line 29 in EHentai.pm has 1887 characters.
• Mixed use of ' and " that cannot be justified by functional differences.
• Trailing spaces that should be trimmed.

Beautifying existing code is obviously not productive, so I am not sure if anything can be done about it ¯\_(ツ)_/¯. Feel free to dismiss and close this issue.

[Difegue]

Been a while since I last did a global PerlTidy pass, so this should alleviate most of your problems.
I've also included the .rc file matching the rules I use at the moment (which did change a bit from when I started 5 years ago...), which gives you a baseline to go along.

If you plan on contributing further, you can use this .rc with a perltidy install and a formatter. (I use https://github.com/kak-tus/perltidy-more for vscode)

Some extras:

• Code width limit is stupid for long strings and comments (ie the base64 pngs in plugin metadata), which is perltidy's default behavior.
• The visual indentation is made by perltidy but I actually really like it, so I leave it in and try to repro it whenever it makes sense.
• The codebase does have issues with variable naming -- perl packages usually go for snakecase buuut short variables are ok in flatcase (extract from perlstyle)
  I usually go with camelcase in other languages but I feel it's not a good fit here.
• ''s should only be used for escaping " easily and vice-versa but I don't really care about that one. 😐

[Difegue]

I've added the above paragraph to the documentation as well -- Closing for now.