#!/usr/bin/perl
BEGIN {(*STDERR = *STDOUT) || die;}
use diagnostics;
use warnings;
use strict;
$| = 1;

use Text::Autoformat qw(autoformat break_TeX);

#--------------------------------------------
# Configuration

# Since vertical spacing is fixed (meaning we do not have 
# the option, at least in this release, of using double 
# spaced or 1.5 spaced lines) all computation is done in 
# units of vertical spacing.  So we need the width to 
# height ratio.  
my $width_to_height = 5/9;

# End configuration
#--------------------------------------------
my $iterations_limit = 10;
my $pi = 3.1412;
my %taf_options = (   left     =>  1, 
                     #right    =>  $width, 
                      justify  =>  'full', 
                      break    =>   break_TeX, 
                     #case     =>  'sentence  ',
                     #widow    =>  1,
                  );

my @messages = ();
push @messages, <<EOF;


                                      It's            
                                   been said            
                                 ever so often            
                               by many an expert            
                             that in ol' plain text            
                               one neer can get a             
                                round tuit, but 
                                   just look             
                                      here            

EOF

push @messages, <<EOF;

  This document is intended to give you a quick overview of the Perl
  programming language, along with pointers to further documentation.
  It is intended as a "bootstrap" guide for those who are new to the
  language, and provides just enough information for you to be able to
  read other peoples' Perl and understand roughly what it's doing, or
  write your own simple scripts.

  This introductory document does not aim to be complete. It does not
  even aim to be entirely accurate. In some cases perfection has been
  sacrificed in the goal of getting the general idea across. You are
  *strongly* advised to follow this introduction with more information
  from the full Perl manual, the table of contents to which can be
  found in perltoc.

EOF

for (@messages)
{
   tuit_top_down_approach($_, 0);
   #tuit_dual_approach($_);
}

sub tuit_top_down_approach
{
   my ($message, $pedastal) = @_;

      $message =  message_as_line($message);

   my ($radius, @slab_widths) = quantify_circle($message);

   my @lines = ();

   my $adjust = -1;
   my $adjust_increment = 1;
   my $original_message = $message;

   while(length $message > $slab_widths[0])
   {
      $adjust += $adjust_increment;
      @lines   = ();
      $message = $original_message;

      @lines   = extract_top_down($original_message, $adjust, 1, \@slab_widths);
      $message = $lines[-1];
      chomp $message;

      if($adjust >= $iterations_limit)
      {
          $adjust = 1; 
          $adjust_increment = -1;
      }
      if($adjust <= -$iterations_limit)
      {
          last;
      }
      $pedastal and last;
   }

   align_tuit(\@lines);
   print "\nThe tuit as is after $adjust adjusts:\n";
   print @lines, "\n\n";
}

sub message_as_line
{
  my $message = shift;
     $message =~ s/^\s+//gm;
     $message =~ s/\s+$//gm;
     $message =~ s/-\n//g;
     $message =~ s/\n/ /g;
     $message =~ s/\s\s+/ /g;

     return $message;
}

sub quantify_circle
{
   my $message = shift;

   my $count   = () = $message =~ m/./g;

   my $area    = $count * $width_to_height; 
   my $radius  = sqrt ($area / $pi);
   
   my @slab_widths = ();
   for (- int $radius .. -1)
   {
     push @slab_widths, int (2 * (sqrt (($radius * $radius) - ($_ * $_)))/$width_to_height + 0.5);
 
   }
   push @slab_widths, (int ($radius * 2 / $width_to_height + 0.5)), reverse @slab_widths;

if(0)
{
   my $check = int ($radius * 2 / $width_to_height + 0.5);
   for (@slab_widths)
   {
       $check += 2 * $_;
   }

   my $layers = int $radius;
   print "count:$count, area:$area, radius:$radius, layers=$layers, check=$check,\n";
   print "slab widths:\n@slab_widths,\n";
}
  
   return $radius, @slab_widths;
}


sub extract_top_down
{
   my ($message, $adjust, $widow, $slabs) = @_;

   # following overrides the global one
   my %taf_options = (   left     =>  1, 
                        #right    =>  $width, 
                         justify  =>  'full', 
                         break    =>   break_TeX, 
                        #case     =>  'sentence  ',
                         widow    =>  1,
                     );
    
   my @lines = ();
   for my $width (@{$slabs})
   {
     my $foo = $width + $adjust;
        $foo > 0 or $foo = 2;
          
        $taf_options{right} = $foo;
        ($widow) and $taf_options{widow} = $foo - 1;

     my $formatted = autoformat $message, {%taf_options};
        if(!($formatted =~ s/^([^\n]+\n)(.+\n)$/$2/s))
        {
           $message = $formatted;
           last;
        }
        push @lines,  $1;
        $message   = message_as_line($formatted);
   }
   push @lines, "$message\n";

   return @lines;
}

sub align_tuit
{
   my $lines = shift;

   for (@{$lines})
   {
        $_ = " "x(40 - 0.5 * length($_)) . $_;
   }
}

__END__