#!/usr/bin/env perl

# Daniel Bowling <swaggboi@slackware.uk>
# Mar 2021

use Mojolicious::Lite;
use Regexp::Common qw{net};
use Digest::SHA qw{sha1_hex};

# The main landing page; pass in the output of the fortune command
get '/' => sub {
    my ($c)     = @_;
    my $fortune = `fortune` || "huh?? no fortune for u\n";
    
    $c->render(fortune => $fortune);
} => 'index';

# Deprecation of IE page
get '/die';

get '/me';

get '/news';

# Process mac address to ula6 ala the ol' ula6.cgi script:
# - Current time of day in 64-bit NTP format
# - Obtain EUI64
# - Cat first with second
# - Compute SHA-1 of third and use least significant 40 bits
# TODO: This ancient code could certainly be cleaned up
get '/ula6' => sub {
    my ($c)  = @_;
    my $mac  = lc $c->param('macaddr'); # Lower-case plz
    my $ula6;

    # Check the MAC
    if ($mac =~ /$RE{net}{MAC}/) {
        # Local vars for this bit
        my (
            $binfield,
            $decfield,
            $digesty,
            $epoch,
            @fields,
            $fulleui,
            $halfone,
            $halftwo,
            $hexfield,
            $uniqueid
            );

        # EUI64
        @fields   = split(/:/, $mac);
        $halfone  = $fields[0] . $fields[1] . $fields[2] . "ff";
        $halftwo  = "fe"       . $fields[3] . $fields[4] . $fields[5];
        $binfield = sprintf "%b", hex $fields[0];
        $decfield = sprintf "%d", hex $fields[0];
        $decfield = ($binfield =~ m/1[01]$/) ? $decfield - 2 : $decfield + 2;
        $binfield = sprintf "%b", int $decfield;
        $hexfield = sprintf "%x", int $decfield;
        $halfone  = $hexfield . $fields[1] . $fields[2] . "ff";
        $fulleui  = $halfone  . $halftwo;

        # Current time of day
        $epoch = time() + 2208988800;

        # Cat with the time
        $digesty   = sha1_hex($epoch . $fulleui);
        ($uniqueid = "fd" . substr $digesty, -10) =~ s/(.{1,4})/$1:/gs;

        # Set the ULA
        $ula6 = $uniqueid . ':/48';
    }

    $c->render(ula6 => $ula6);
};

# Send it
app->start();