#/usr/bin/perl

use strict;

use constant TRUE  => 1;
use constant FALSE => 0;

   our $debug = FALSE;

   print truncate_string("   abcdefg   ",256);


   sub truncate_string{
      my ($string,$trunc_length) = @_;

      $string =~ m/^(\s*)(.*?)(\s*)$/;
      my $space_count_pre   = length($1);
      my $letter_count      = length($2);
      my $space_text_length = $space_count_pre + $letter_count;

      sub debug{
         print "Beginning Spaces: $space_count_pre\n";
         print "Text Length:      $letter_count\n";
         print "Trunc Length:     $trunc_length\n";
         print "String:           \"$string\"\n\n";
      }
      debug() if $debug;

      # if the final string is already less than the current number of alphanumeric characters
      if ($trunc_length <= $letter_count){$string = substr($2,0,$trunc_length);return $string;}

      # if the final string is bigger than the beginning spaces + text
      if ($trunc_length > $space_text_length) {$string = "$1$2" . substr($3,0,$trunc_length - $space_text_length);return $string;}

      # if the final string is bigger than text, but smaller than beginning spaces + text
      if ($trunc_length > $letter_count && $trunc_length < $space_text_length){$string = substr($1,0,$trunc_length - $space_text_length) . $2;return $string;}
   }