package MyBuffer;

use strict;
use vars qw|$MYBUF $MYFILL|;

sub new {
  my $this = shift;
  my $class = ref ($this) || $this;
  my $self = bless ({ buffer_size => 1024,
		      fill_byte => "\0",
		      debug => 0,
		      @_ ,
		    }, $class);
  return $self->init ();
}

sub init {

  my $self = shift;
  $MYBUF = "";
  $self->{'fill_byte'} .= "\0";
  $self->{'fill_byte'} = substr ($self->{'fill_byte'}, 0, 1);
  $MYFILL = $self->{'fill_byte'} x $self->{'buffer_size'};
  return $self;

}

sub read {

  my $self = shift;
  my $num_bytes = shift || $self->{'buffer_size'};
  my $strlen = length ($MYBUF);
  my $retstr = "";

#  print STDERR "reading " . $num_bytes . ".";

  if ($strlen < $num_bytes) {
    $retstr = $MYBUF . substr ($MYFILL, ($self->{'buffer_length'} - ($num_bytes - $strlen)));
    print STDERR "UNDERRUN\n";
    $MYBUF = "";
  } else {
    $retstr = substr ($MYBUF, 0, $num_bytes, "");
  }

#  print STDERR "  length is " . length ($MYBUF) . "\n";

  return $retstr;

}

sub write {

  my $self = shift;
  my $bytes = shift;
  $MYBUF .= $bytes;


  print STDERR "wrote   " . length ($bytes) . ".";
  print STDERR "  length is " . length ($MYBUF) . "\n";

  return $self;

}

sub remaining {

  my $self = shift;
  return (length ($MYBUF));

}

sub contents {
  my $self = shift;
  my $buf = "$MYBUF";
  return $buf;
}

1;