<?php

/////////////////////////////////////////////////////////////////
/// getID3() by James Heinrich <info@getid3.org> //
// available at https://github.com/JamesHeinrich/getID3 //
// or https://www.getid3.org //
// or http://getid3.sourceforge.net //
// see readme.txt for more details //
/////////////////////////////////////////////////////////////////
// //
// module.tag.id3v1.php //
// module for analyzing ID3v1 tags //
// dependencies: NONE //
// ///
/////////////////////////////////////////////////////////////////

if (!defined('GETID3_INCLUDEPATH')) { // prevent path-exposing attacks that access modules directly on public webservers
exit;
}

class getid3_id3v1 extends getid3_handler
{
/**
* @return bool
*/
public function Analyze() {
$info = &$this->getid3->info;

if (!getid3_lib::intValueSupported($info['filesize'])) {
$this->warning('Unable to check for ID3v1 because file is larger than '.round(PHP_INT_MAX / 1073741824).'GB');
return false;
}

if($info['filesize'] < 256) {
$this->fseek(-128, SEEK_END);
$preid3v1 = '';
$id3v1tag = $this->fread(128);
} else {
$this->fseek(-256, SEEK_END);
$preid3v1 = $this->fread(128);
$id3v1tag = $this->fread(128);
}


if (substr($id3v1tag, 0, 3) == 'TAG') {

$info['avdataend'] = $info['filesize'] - 128;

$ParsedID3v1 = array();
$ParsedID3v1['title'] = $this->cutfield(substr($id3v1tag, 3, 30));
$ParsedID3v1['artist'] = $this->cutfield(substr($id3v1tag, 33, 30));
$ParsedID3v1['album'] = $this->cutfield(substr($id3v1tag, 63, 30));
$ParsedID3v1['year'] = $this->cutfield(substr($id3v1tag, 93, 4));
$ParsedID3v1['comment'] = substr($id3v1tag, 97, 30); // can't remove nulls yet, track detection depends on them
$ParsedID3v1['genreid'] = ord(substr($id3v1tag, 127, 1));

// If second-last byte of comment field is null and last byte of comment field is non-null
// then this is ID3v1.1 and the comment field is 28 bytes long and the 30th byte is the track number
if (($id3v1tag[125] === "\x00") && ($id3v1tag[126] !== "\x00")) {
$ParsedID3v1['track_number'] = ord(substr($ParsedID3v1['comment'], 29, 1));
$ParsedID3v1['comment'] = substr($ParsedID3v1['comment'], 0, 28);
}
$ParsedID3v1['comment'] = $this->cutfield($ParsedID3v1['comment']);

$ParsedID3v1['genre'] = $this->LookupGenreName($ParsedID3v1['genreid']);
if (!empty($ParsedID3v1['genre'])) {
unset($ParsedID3v1['genreid']);
}
if (empty($ParsedID3v1['genre']) || ($ParsedID3v1['genre'] == 'Unknown')) {
unset($ParsedID3v1['genre']);
}

foreach ($ParsedID3v1 as $key => $value) {
$ParsedID3v1['comments'][$key][0] = $value;
}
$ID3v1encoding = $this->getid3->encoding_id3v1;
if ($this->getid3->encoding_id3v1_autodetect) {
// ID3v1 encoding detection hack START
// ID3v1 is defined as always using ISO-8859-1 encoding, but it is not uncommon to find files tagged with ID3v1 using Windows-1251 or other character sets
// Since ID3v1 has no concept of character sets there is no certain way to know we have the correct non-ISO-8859-1 character set, but we can guess
foreach ($ParsedID3v1['comments'] as $tag_key => $valuearray) {
foreach ($valuearray as $key => $value) {
if (preg_match('#^[\\x00-\\x40\\x80-\\xFF]+$#', $value) && !ctype_digit((string) $value)) { // check for strings with only characters above chr(128) and punctuation/numbers, but not just numeric strings (e.g. track numbers or years)
foreach (array('Windows-1251', 'KOI8-R') as $id3v1_bad_encoding) {
if (function_exists('mb_convert_encoding') && @mb_convert_encoding($value, $id3v1_bad_encoding, $id3v1_bad_encoding) === $value) {
$ID3v1encoding = $id3v1_bad_encoding;
$this->warning('ID3v1 detected as '.$id3v1_bad_encoding.' text encoding in '.$tag_key);
break 3;
} elseif (function_exists('iconv') && @iconv($id3v1_bad_encoding, $id3v1_bad_encoding, $value) === $value) {
$ID3v1encoding = $id3v1_bad_encoding;
$this->warning('ID3v1 detected as '.$id3v1_bad_encoding.' text encoding in '.$tag_key);
break 3;
}
}
}
}
}
// ID3v1 encoding detection hack END
}

// ID3v1 data is supposed to be padded with NULL characters, but some taggers pad with spaces
$GoodFormatID3v1tag = $this->GenerateID3v1Tag(
$ParsedID3v1['title'],
$ParsedID3v1['artist'],
$ParsedID3v1['album'],
$ParsedID3v1['year'],
(isset($ParsedID3v1['genre']) ? $this->LookupGenreID($ParsedID3v1['genre']) : false),
$ParsedID3v1['comment'],
(!empty($ParsedID3v1['track_number']) ? $ParsedID3v1['track_number'] : ''));
$ParsedID3v1['padding_valid'] = true;
if ($id3v1tag !== $GoodFormatID3v1tag) {
$ParsedID3v1['padding_valid'] = false;
$this->warning('Some ID3v1 fields do not use NULL characters for padding');
}

$ParsedID3v1['tag_offset_end'] = $info['filesize'];
$ParsedID3v1['tag_offset_start'] = $ParsedID3v1['tag_offset_end'] - 128;

$info['id3v1'] = $ParsedID3v1;
$info['id3v1']['encoding'] = $ID3v1encoding;
}

if (substr($preid3v1, 0, 3) == 'TAG') {
// The way iTunes handles tags is, well, brain-damaged.
// It completely ignores v1 if ID3v2 is present.
// This goes as far as adding a new v1 tag *even if there already is one*

// A suspected double-ID3v1 tag has been detected, but it could be that
// the "TAG" identifier is a legitimate part of an APE or Lyrics3 tag
if (substr($preid3v1, 96, 8) == 'APETAGEX') {
// an APE tag footer was found before the last ID3v1, assume false "TAG" synch
} elseif (substr($preid3v1, 119, 6) == 'LYRICS') {
// a Lyrics3 tag footer was found before the last ID3v1, assume false "TAG" synch
} else {
// APE and Lyrics3 footers not found - assume double ID3v1
$this->warning('Duplicate ID3v1 tag detected - this has been known to happen with iTunes');
$info['avdataend'] -= 128;
}
}

return true;
}

/**
* @param string $str
*
* @return string
*/
public static function cutfield($str) {
return trim(substr($str, 0, strcspn($str, "\x00")));
}

/**
* @param bool $allowSCMPXextended
*
* @return string[]
*/
public static function ArrayOfGenres($allowSCMPXextended=false) {
static $GenreLookup = array(
0 => 'Blues',
1 => 'Classic Rock',
2 => 'Country',
3 => 'Dance',
4 => 'Disco',
5 => 'Funk',
6 => 'Grunge',
7 => 'Hip-Hop',
8 => 'Jazz',
9 => 'Metal',
10 => 'New Age',
11 => 'Oldies',
12 => 'Other',
13 => 'Pop',
14 => 'R&B',
15 => 'Rap',
16 => 'Reggae',
17 => 'Rock',
18 => 'Techno',
19 => 'Industrial',
20 => 'Alternative',
21 => 'Ska',
22 => 'Death Metal',
23 => 'Pranks',
24 => 'Soundtrack',
25 => 'Euro-Techno',
26 => 'Ambient',
27 => 'Trip-Hop',
28 => 'Vocal',
29 => 'Jazz+Funk',
30 => 'Fusion',
31 => 'Trance',
32 => 'Classical',
33 => 'Instrumental',
34 => 'Acid',
35 => 'House',
36 => 'Game',
37 => 'Sound Clip',
38 => 'Gospel',
39 => 'Noise',
40 => 'Alt. Rock',
41 => 'Bass',
42 => 'Soul',
43 => 'Punk',
44 => 'Space',
45 => 'Meditative',
46 => 'Instrumental Pop',
47 => 'Instrumental Rock',
48 => 'Ethnic',
49 => 'Gothic',
50 => 'Darkwave',
51 => 'Techno-Industrial',
52 => 'Electronic',
53 => 'Pop-Folk',
54 => 'Eurodance',
55 => 'Dream',
56 => 'Southern Rock',
57 => 'Comedy',
58 => 'Cult',
59 => 'Gangsta Rap',
60 => 'Top 40',
61 => 'Christian Rap',
62 => 'Pop/Funk',
63 => 'Jungle',
64 => 'Native American',
65 => 'Cabaret',
66 => 'New Wave',
67 => 'Psychedelic',
68 => 'Rave',
69 => 'Showtunes',
70 => 'Trailer',
71 => 'Lo-Fi',
72 => 'Tribal',
73 => 'Acid Punk',
74 => 'Acid Jazz',
75 => 'Polka',
76 => 'Retro',
77 => 'Musical',
78 => 'Rock & Roll',
79 => 'Hard Rock',
80 => 'Folk',
81 => 'Folk/Rock',
82 => 'National Folk',
83 => 'Swing',
84 => 'Fast-Fusion',
85 => 'Bebob',
86 => 'Latin',
87 => 'Revival',
88 => 'Celtic',
89 => 'Bluegrass',
90 => 'Avantgarde',
91 => 'Gothic Rock',
92 => 'Progressive Rock',
93 => 'Psychedelic Rock',
94 => 'Symphonic Rock',
95 => 'Slow Rock',
96 => 'Big Band',
97 => 'Chorus',
98 => 'Easy Listening',
99 => 'Acoustic',
100 => 'Humour',
101 => 'Speech',
102 => 'Chanson',
103 => 'Opera',
104 => 'Chamber Music',
105 => 'Sonata',
106 => 'Symphony',
107 => 'Booty Bass',
108 => 'Primus',
109 => 'Porn Groove',
110 => 'Satire',
111 => 'Slow Jam',
112 => 'Club',
113 => 'Tango',
114 => 'Samba',
115 => 'Folklore',
116 => 'Ballad',
117 => 'Power Ballad',
118 => 'Rhythmic Soul',
119 => 'Freestyle',
120 => 'Duet',
121 => 'Punk Rock',
122 => 'Drum Solo',
123 => 'A Cappella',
124 => 'Euro-House',
125 => 'Dance Hall',
126 => 'Goa',
127 => 'Drum & Bass',
128 => 'Club-House',
129 => 'Hardcore',
130 => 'Terror',
131 => 'Indie',
132 => 'BritPop',
133 => 'Negerpunk',
134 => 'Polsk Punk',
135 => 'Beat',
136 => 'Christian Gangsta Rap',
137 => 'Heavy Metal',
138 => 'Black Metal',
139 => 'Crossover',
140 => 'Contemporary Christian',
141 => 'Christian Rock',
142 => 'Merengue',
143 => 'Salsa',
144 => 'Thrash Metal',
145 => 'Anime',
146 => 'JPop',
147 => 'Synthpop',
148 => 'Abstract',
149 => 'Art Rock',
150 => 'Baroque',
151 => 'Bhangra',
152 => 'Big Beat',
153 => 'Breakbeat',
154 => 'Chillout',
155 => 'Downtempo',
156 => 'Dub',
157 => 'EBM',
158 => 'Eclectic',
159 => 'Electro',
160 => 'Electroclash',
161 => 'Emo',
162 => 'Experimental',
163 => 'Garage',
164 => 'Global',
165 => 'IDM',
166 => 'Illbient',
167 => 'Industro-Goth',
168 => 'Jam Band',
169 => 'Krautrock',
170 => 'Leftfield',
171 => 'Lounge',
172 => 'Math Rock',
173 => 'New Romantic',
174 => 'Nu-Breakz',
175 => 'Post-Punk',
176 => 'Post-Rock',
177 => 'Psytrance',
178 => 'Shoegaze',
179 => 'Space Rock',
180 => 'Trop Rock',
181 => 'World Music',
182 => 'Neoclassical',
183 => 'Audiobook',
184 => 'Audio Theatre',
185 => 'Neue Deutsche Welle',
186 => 'Podcast',
187 => 'Indie-Rock',
188 => 'G-Funk',
189 => 'Dubstep',
190 => 'Garage Rock',
191 => 'Psybient',

255 => 'Unknown',

'CR' => 'Cover',
'RX' => 'Remix'
);

static $GenreLookupSCMPX = array();
if ($allowSCMPXextended && empty($GenreLookupSCMPX)) {
$GenreLookupSCMPX = $GenreLookup;
// http://www.geocities.co.jp/SiliconValley-Oakland/3664/alittle.html#GenreExtended
// Extended ID3v1 genres invented by SCMPX
// Note that 255 "Japanese Anime" conflicts with standard "Unknown"
$GenreLookupSCMPX[240] = 'Sacred';
$GenreLookupSCMPX[241] = 'Northern Europe';
$GenreLookupSCMPX[242] = 'Irish & Scottish';
$GenreLookupSCMPX[243] = 'Scotland';
$GenreLookupSCMPX[244] = 'Ethnic Europe';
$GenreLookupSCMPX[245] = 'Enka';
$GenreLookupSCMPX[246] = 'Children\'s Song';
$GenreLookupSCMPX[247] = 'Japanese Sky';
$GenreLookupSCMPX[248] = 'Japanese Heavy Rock';
$GenreLookupSCMPX[249] = 'Japanese Doom Rock';
$GenreLookupSCMPX[250] = 'Japanese J-POP';
$GenreLookupSCMPX[251] = 'Japanese Seiyu';
$GenreLookupSCMPX[252] = 'Japanese Ambient Techno';
$GenreLookupSCMPX[253] = 'Japanese Moemoe';
$GenreLookupSCMPX[254] = 'Japanese Tokusatsu';
//$GenreLookupSCMPX[255] = 'Japanese Anime';
}

return ($allowSCMPXextended ? $GenreLookupSCMPX : $GenreLookup);
}

/**
* @param string $genreid
* @param bool $allowSCMPXextended
*
* @return string|false
*/
public static function LookupGenreName($genreid, $allowSCMPXextended=true) {
switch ($genreid) {
case 'RX':
case 'CR':
break;
default:
if (!is_numeric($genreid)) {
return false;
}
$genreid = intval($genreid); // to handle 3 or '3' or '03'
break;
}
$GenreLookup = self::ArrayOfGenres($allowSCMPXextended);
return (isset($GenreLookup[$genreid]) ? $GenreLookup[$genreid] : false);
}

/**
* @param string $genre
* @param bool $allowSCMPXextended
*
* @return string|false
*/
public static function LookupGenreID($genre, $allowSCMPXextended=false) {
$GenreLookup = self::ArrayOfGenres($allowSCMPXextended);
$LowerCaseNoSpaceSearchTerm = strtolower(str_replace(' ', '', $genre));
foreach ($GenreLookup as $key => $value) {
if (strtolower(str_replace(' ', '', $value)) == $LowerCaseNoSpaceSearchTerm) {
return $key;
}
}
return false;
}

/**
* @param string $OriginalGenre
*
* @return string|false
*/
public static function StandardiseID3v1GenreName($OriginalGenre) {
if (($GenreID = self::LookupGenreID($OriginalGenre)) !== false) {
return self::LookupGenreName($GenreID);
}
return $OriginalGenre;
}

/**
* @param string $title
* @param string $artist
* @param string $album
* @param string $year
* @param int $genreid
* @param string $comment
* @param int|string $track
*
* @return string
*/
public static function GenerateID3v1Tag($title, $artist, $album, $year, $genreid, $comment, $track='') {
$ID3v1Tag = 'TAG';
$ID3v1Tag .= str_pad(trim(substr($title, 0, 30)), 30, "\x00", STR_PAD_RIGHT);
$ID3v1Tag .= str_pad(trim(substr($artist, 0, 30)), 30, "\x00", STR_PAD_RIGHT);
$ID3v1Tag .= str_pad(trim(substr($album, 0, 30)), 30, "\x00", STR_PAD_RIGHT);
$ID3v1Tag .= str_pad(trim(substr($year, 0, 4)), 4, "\x00", STR_PAD_LEFT);
if (!empty($track) && ($track > 0) && ($track <= 255)) {
$ID3v1Tag .= str_pad(trim(substr($comment, 0, 28)), 28, "\x00", STR_PAD_RIGHT);
$ID3v1Tag .= "\x00";
if (gettype($track) == 'string') {
$track = (int) $track;
}
$ID3v1Tag .= chr($track);
} else {
$ID3v1Tag .= str_pad(trim(substr($comment, 0, 30)), 30, "\x00", STR_PAD_RIGHT);
}
if (($genreid < 0) || ($genreid > 147)) {
$genreid = 255; // 'unknown' genre
}
switch (gettype($genreid)) {
case 'string':
case 'integer':
$ID3v1Tag .= chr(intval($genreid));
break;
default:
$ID3v1Tag .= chr(255); // 'unknown' genre
break;
}

return $ID3v1Tag;
}

}