#!/usr/local/bin/perl -w

use strict;

#use sort '_quicksort';
#use sort '_mergesort';

use Benchmark qw(cmpthese);

use Netscape::History;
use Netscape::HistoryURL;

my $history = new Netscape::History("/home/parv/.netscape/history.dat");
my %hist;

while ( defined (my $url = $history->next_url()) )
{
  ( $hist{ $url } = $url->title() ) =~ s/\s+/ /g;
  $hist{ $url } = $hist{ $url } || "--";
}
$history->close();

#  print some url statistics
printf
  "URLs: %u\n  min: %u,  max: %u\n  mean: %0.2f, median: %0.2f\n\n"
  , @{ stats() };


cmpthese( -10 , { 'ST'=> \&schwartz , 'GRT'=> \&guttman_rosler });


#  Guttman-Rosler Transform
sub guttman_rosler
{
  print STDERR +($hist{$_} , "\n", $_ , "\n\n")
    foreach
      #  extract the sorted complete URL list
      map { (split '\0' , $_ , 2)[1] }
      sort
        #  set up for extracting the complete URL & sortkeys
        map { #  extract host/domain components in reverse order
              my $scheme_end = index($_, '://') + 3;

              my @host =
                reverse
                  split '\.' , (split '/' , substr($_ , $scheme_end) , 2)[0];

              #  put domain at front; everything else afterwords
              #  ----
              #  poo.koo -> poo.koo
              #  web.poo.koo:80 -> poo.koo:80.web
              #  rand.web.poo.koo -> poo.koo.web.rand
              #  ----
              lc( +(scalar @host > 1 ? $host[1] . '.' : '')
                  . $host[0]
                  . ( scalar @host < 3
                      ? '' : '.' . join('.' , @host[2..$#host])
                    )
                  . substr($_ , length(join '.', @host) + $scheme_end)
                )
              . "\x00" . $_
            } keys %hist;
  return;
}

#  Schwartzian Transform
sub schwartz
{
  print STDERR +($hist{$_} , "\n", $_ , "\n\n")
    foreach
      #  extract the sorted complete URL list
      map { $_->[0] }

      #  sort on massged host name or the complete url
      sort { $a->[1] cmp $b->[1] }

        #  set up for extracting the complete URL & sortkeys
        map { #  extract host/domain components in reverse order
              my @host =
                reverse split '\.'
                          , ( split '/' , substr($_ , index($_, '://') + 3)
                                        , 2
                            )[0];

              [ #  current URL
                $_

              , #  put domain at front; everything else afterwords
                #  ----
                #  poo.koo -> poo.koo
                #  web.poo.koo:80 -> poo.koo:80.web
                #  rand.web.poo.koo -> poo.koo.web.rand
                #  ----
                lc +(scalar @host > 1 ? $host[1] . '.' : '')
                  . $host[0]
                  . +( scalar @host < 3
                        ? '' : '.' . join('.' , @host[2..$#host])
                      )
                  . substr($_ , length(join '.', @host) + index($_, '://') + 3)
              ]
            } keys %hist;
  return;
}

#  calculate some URL statistics
sub stats
{
  my $total = 0;
  my @len;

  foreach ( sort {length $a <=> length $b} keys %hist )
  {
    my $len = length $_;

    $total += $len;

    push @len, $len;
  }

  my $number = scalar keys %hist;

  my $mid_pt = int($number / 2);
  my $median =
    $mid_pt % 2 == 0 ? $len[$mid_pt]
                     : ($len[$mid_pt] + $len[$mid_pt + 1]) / 2;

  return [  $number , $len[0] , $len[-1] , $total/$number , $median ];
}