#!/usr/bin/perl

use warnings;
use strict;

package Konto;

    sub new {
        my $classname = shift;
        my $nummer = shift;
        my $name = shift;
        my $self = {nummer => $nummer,
                    name   => $name,
                    sollsum => 0,
                    habensum => 0,
                    buchungen => [],
                    saldo => 0,
                    saldoisin => ""};
        return bless($self, $classname);
    }

    sub bucheSoll {
        my $self = shift;
        my $soll = shift;
        my $bsatz = shift;
        $self->{sollsum} += $soll;
        push(@{$self->{buchungen}}, $bsatz);
    }

    sub bucheHaben {
        my $self = shift;
        my $haben = shift;
        my $bsatz = shift;
        $self->{habensum} += $haben;
        push(@{$self->{buchungen}}, $bsatz);
    }

    sub calcSaldo {
        my $self = shift;

        if ($self->{sollsum} > $self->{habensum}) {
            $self->{saldo} = $self->{sollsum} - $self->{habensum};
            $self->{saldoisin} = "soll";

        } elsif ($self->{sollsum} < $self->{habensum}) {
            $self->{saldo} = $self->{habensum} - $self->{sollsum};
            $self->{saldoisin} = "haben";

        } else {
            $self->{saldo} = 0;
            $self->{saldoisin} = "0";
        }
    }

    sub clear {
        my $self = shift;
        $self->{sollsum} = 0;
        $self->{habensum} = 0;
        $self->{buchungen} = [];
        $self->{saldo} = 0;
        $self->{saldoisin} = "";
    }
 
package main;

my $bankkonto = Konto -> new(1200, "Bank");
$bankkonto -> bucheHaben(13.36, "01.03.2011;X123;Telefonkosten;13,36;4920;1200");
$bankkonto -> bucheHaben(2.54, "01.03.2011;X123;VSt. Telefonkosten;2,54;1577;1200");
$bankkonto -> calcSaldo();
print "Saldo: $bankkonto->{saldo}\n";
print "Soll oder Haben: $bankkonto->{saldoisin}\n";