#!/usr/bin/perl -T

# Diese Datei MUSS 700-Filepermissions haben, da hier das FTP-Passwort
# gespeichert wird!

#
# MP3-Archiv indizieren und in einer XML-Datei speichern
#

# ----- config vars

my $mp3_dir = '/mp3z';			# rekursiv zu indizierendes Verzeichnis
my $xmlbase = '/tmp/mp3_list.xml';	# Zielort der XML-Datei
my $ping_host = 'foo.bar.de';		# vor Indexbeginn zu pingender Host
my $ftp_user = 'www';			# FTP-User
my $ftp_pass = 'strenggeheim';		# FTP-Passwd
my $ftp_host = 'foo.bar.de';		# FTP-Remote-Host
my $ftp_path = '/mymp3z';		# Zielverz. FTP-Server
my $status_file = "/tmp/mp3_status";	# the status file

# ----- public vars

my (%change, %inode) = ();
my @mp3z;

# ----- used modules

use strict;
use MP3::Info;
use MIME::QuotedPrint;
use Net::FTP;
use Net::Ping;
use XML::Writer;

# ----- some subs to check the necessarity of updating the database

sub is_changed {

  $change{new} = 0;
  $inode{new} = 0;
  my $dummy;

  foreach (@mp3z) {
    ($change{cur}, $inode{cur}, $dummy) = split /;/, $_;
    $change{new} += $change{cur};
    $inode{new}  += $inode{cur};
  }

  open (STATUS, "<$status_file") || return 1;
  ($change{old}, $inode{old}) = split /;/, <STATUS>;
  close(STATUS);

  if (($change{new} == $change{old}) and ($inode{new} == $inode{old})) {
    return 0;
  }
  else {
    return 1;
  }
}

sub write_status {
  open (STATUS, ">$status_file") || die "Konnte Statusfile $status_file nicht anlegen!\n";
  print STATUS $change{new} . ";" . $inode{new};
  close (STATUS);
}

# ----- check via icmp ping whether remote host is reachable

my $p = Net::Ping->new('icmp');		# requires root privileges !

if ($p->ping($ping_host, my $timeout) == 0) {
  print "exit: MP3-Fileserver nicht erreichbar!\n";
  exit ();
}

# ----- save recursive directory listing into a hash (via BSD find)

$ENV{'PATH'} = "";
open (PIPE, "/usr/bin/find $mp3_dir/* -path '/*/.*' -prune -o -iname '*.MP*' -printf \"%s;%i;%p\n\" |");
@mp3z = <PIPE>;
close (PIPE);

if (!is_changed) {
  print "exit: Kein Update notwendig!\n";
  exit ();
}

# ----- read mp3 information and write to xml file

umask 002;
my $xmlfile = new IO::File (">$xmlbase") or die $!;
my $xml = new XML::Writer (
  DATA_MODE   => 1,
  DATA_INDENT => 2,
  OUTPUT      => $xmlfile
);
$xml->xmlDecl ("ISO-8859-1", "no");
$xml->doctype ("mp3archive", "", "mp3archive.dtd");
$xml->startTag("mp3archive");

my ($tag, $info);
foreach my $mp3 (@mp3z) {
  $mp3 =~ s/.*;//g;
  chomp $mp3;
  $tag = get_mp3tag ($mp3);
  $info = get_mp3info ($mp3);
  $xml->startTag ("mp3", "filename" => encode_qp ($mp3),  "year" => $tag->{'YEAR'}, "time" => $info->{'TIME'});
  $xml->startTag ("artist");
  $xml->characters (encode_qp ($tag->{'ARTIST'}));
  $xml->endTag ("artist");
  $xml->startTag ("title");
  $xml->characters (encode_qp ($tag->{'TITLE'}));
  $xml->endTag ("title");
  $xml->endTag("mp3");
}

$xml->endTag ("mp3archive");
$xml->end;
$xmlfile->close();

# ----- write the status file

write_status;

# ----- put the created xml file onto the webserver via FTP

my $fname = $xmlbase;
my $dir = $xmlbase;
$fname =~ s/(.*)\///g;
my $myfname = $fname;
$myfname =~ s/([^A-Za-z0-9_-].?)/\\$1/g;
$dir =~ s/$myfname//g;

chdir($dir);
my $ftp = Net::FTP->new ($ftp_host, Debug => 0) || die "Keine FTP-Verbindung zum Webserver!\n";
$ftp->login ($ftp_user,$ftp_pass) || die "Fehler beim Einloggen via FTP!\n";
$ftp->cwd ($ftp_path);
$ftp->put ($fname) || "Fehler beim Dateiupload auf FTP-Server!\n";
$ftp->quit () || "Fehler beim Ausloggen vom FTP-Server!\n";