#!/usr/bin/perl -w

# Copyright (C) 2004 Mike Irwin <rhythmicus@pobox.com>

# This program is free software; you can redistribute it and/or modify it under
# the same terms as Perl itself.

# This program comes with ABSOLUTELY NO WARRANTY.

# See `perldoc perlartistic'.

use strict;
use POSIX qw(floor);

use constant SPLIT_SIZE => 3996;

foreach (@ARGV) {
    die "$_: $!\n" unless -r;

    my $size = -s _;
    next unless $size > 4096;

    my $last_size = $size % SPLIT_SIZE;
    my $num_files = floor( $size / SPLIT_SIZE );
    $num_files++ if $last_size;

    my ( $file, $read, $j, $data, $link );
    my $width = length($num_files);

    open OF, "+<$_" or die "$_: $!\n";

    for ( my $i = $num_files ; $i > 0 ; $i-- ) {
        $file = sprintf( "%s.%0*d", $_, $width, $i );
        $read = 0;

        open NF, ">$file" or die "$file: $!\n";
        seek OF,
          -( ( $i == $num_files and $last_size ) ? $last_size : SPLIT_SIZE ), 2;

        while ( $j = read OF, $data, SPLIT_SIZE ) {
            print NF $data;
            $read += $j;
        }

        print NF "...\n\n<a href=\"$link\">Next Page</a>"
          if ( $i < $num_files );

        close NF;
        truncate OF, $size -= $read;
        $link = $file;
    }

    close OF;
    unlink or warn "$_: $!\n";
}