#!/usr/bin/perl
# ^^^^^^^^^^^^^ change this to suit your system
#               if you don't know what it should be,
#               type this at a prompt: which perl
#      ** or **
#               if perl is in your path somewhere you can erase
#               all of the above, and uncomment the 2 lines below:
eval 'exec perl -S $0 "$@"'
  if 0;
#
# don't modify below here
#-------------------------
$ver = '1.2';
# chcase 1.2
# Changes case of filenames
# http://www.blemished.net/chcase.html
# supermike@blemished.net
#
# 1.2 - June 22, 2000
#	Added -n since escape characters don't work on all terminals
#       Added -l to rename & follow symbolic links
#       Allowed options to be put together eg: chcase -rdou ...
# 1.1 - Feb 29, 2000
#       Added ability to supply perl expressions
# 1.0 - Jan 26, 2000
#       Initial Release

sub ERR {
print "\nchcase $ver\n";
if (shift) {
print<<EOT;
EXAMPLES:
> chcase My.DOC *.JPG FileName.txt
  => these specific files are changed to lower case

> chcase -rd '*'
  => all files and sub dirs to lower case, start in current dir, recurse

> chcase -s pics '*.jpg' '*.gif'
  => rename .jpg and .gif files in pics dir to lower case

> chcase -rous /tmp/junk 'a??b*.txt'
  => starting from /tmp/junk and recursing, change files matching this
     mask to all upper case, overwrite if file exists

> chcase -x 's/99dec/jan2000/' -x 's/ /_/g' '*.doc'
  => renames *.doc files replacing 99dec with jan2000,
     and replacing all spaces with underscores

> chcase -x 'tr/a-zA-Z0-9.//cd' -x 's/jpg/jpg/i' '*'
  => removes all non-alphanumeric characters except for '.' and
     changes the pattern "jpg" to lower case if it isn't already

> chcase -r
  => displays directory structure
EOT
} else {
print<<EOT;
USAGE:
chcase [-erdouqnl] [-s <dir>] [-x '<perl exp>'] '<mask>'

       -e       : Print EXAMPLES - very helpful!
       -r       : Rename recursively
       -d       : Also rename subdirectories
       -o       : Overwrite if file exists
       -u       : Change to upper case (default is lower)
       -q       : Quiet mode (no output)
       -n       : No escape characters (for bold output)
       -l       : Rename & follow symbolic links (default is not to)
       -s <dir> : Specify starting directory

-x '<perl exp>' : Perl expression to operate on filename
                  usually s/// or tr///  (yes you need the quotes)
                  case of filename not changed when this option used
                  you can supply multiple expressions

       '<mask>' : Mask to rename  (quotes are nice to have here)
                  not case sensitive, you can use multiple masks
             -or- just supply the filename(s) on the command line

EOT
}
exit;
}

sub chcase {
 $_ = $old = shift;
 foreach $m (@mask) {
   if (/^$m$/i) {
     if (@exp) { foreach $x (@exp) { eval $x; } }
     else { $_ = $upper ? uc : lc; }
     return($_) if (-d);
     return($_) if (!$overw && -f || ($old eq $_));
     $error = (rename($old, $_)) ? '' : "$bold -> cannot rename$unbold";
     if (-d) { print @h, "$bold$old/  =>  $_$unbold\n" unless $quiet; }
     else { print @h, "$old  =>  $_$error\n" unless $quiet; }
   }
 }
 return($_);
}

sub procdir {
 $_ = shift;
 chdir($_) || die "Couldn't chdir into $_\n$!";
 print @h, "$bold$_$unbold\n" unless $quiet;
 push @h, '|__ ';
 opendir(D,'.');
 foreach (readdir(D)) {
   next if (($_ eq '.') || ($_ eq '..'));
   next if (-l && !$links);
   if (-d) {
     if ($rendir) { $_ = &chcase($_); next if $error; }
     if ($recur) { &procdir($_); chdir('..'); pop @h; }
   } else { &chcase($_); }
 }
 closedir(D);
}


$bold   = "\033[01m";
$unbold = "\033[0m";
$dir = '.';

&ERR unless @ARGV;
while (@ARGV) {
 $_ = shift;
 if (/^-/) {
   &ERR unless /^-[erdouqnlsx]+$/;
   /e/ && &ERR(1);
   /r/ && $recur++;
   /d/ && $rendir++;
   /o/ && $overw++;
   /u/ && $upper++;
   /q/ && $quiet++;
   /n/ && ($bold=$unbold='');
   /l/ && $links++;
   /s/ && ($dir = shift) && ($dir =~ s/\/$//);
   /x/ && (push @exp, shift);
 } else {
   if (/(.*)\/([^\/]*)$/) { $dir = $1; $_ = $2; }
   s/\\/\\\\/g;
   s/\./\\./g; s/\+/\\+/g; s/\[/\\[/g;
   s/\]/\\]/g; s/\|/\\|/g; s/\^/\\^/g;
   s/\*/\.\*/g; s/\?/\./g;
   push @mask, $_;
 }
}

&procdir($dir);