#!/usr/bin/perl -w

use strict;
use warnings;
use DBI;

my ($dbh, $sth);
my %software;
my @installed;
my $iid = '1';		# Inventar-ID

# main

$dbh = &connect();

&fetch_software();
&fetch_installed($iid);
&html_selection();

$dbh->disconnect();
exit(0);

# subs

sub is_in {

  # is_in gibt die Anzahl an Übereinstimmungen eines Elementes
  # zu einer Menge in einem Array zurück.

  my $test = shift @_;
  my @in = @_;
  my $answer = 0;
  for (@in) {
    $answer++ if ($test eq $_);
  }
  return $answer;
}

sub connect {
   return DBI->connect ("DBI:mysql:host=192.168.0.1;database=meine",
               "ich", "geheim", {PrintError => 0, RaiseError => 1});
}

sub fetch_installed {

  my $iid = shift @_;
  $sth = $dbh->prepare ("	SELECT SOID
  						FROM nutzt_software
  						WHERE IID = $iid
  					  ");

  $sth->execute();
  while (my ($soid) = $sth->fetchrow_array()) { push @installed, $soid; }
  $sth->finish();
}

sub fetch_software {

  $sth = $dbh->prepare ("	SELECT SOID, Produkt
  							FROM Software		");
  $sth->execute();

  while (my ($soid, $produkt) = $sth->fetchrow_array()) {
    $software{$soid}=$produkt;
    }
  $sth->finish();
}

sub html_selection {
  print "<select name='Installationen'>\n";
  for (sort(keys(%software))) {
    if (&is_in($_, @installed)) {
        print "<option selected>$software{$_}</option>\n";
      } else {
        print "<option>$software{$_}</option>\n";
      }
    }
  print "</select>\n";
}