<?php
// a map of labels to encodings
$labels = [
	'unicode-1-1-utf-8'   => "UTF-8",
	'unicode11utf8'       => "UTF-8",
	'unicode20utf8'       => "UTF-8",
	'utf-8'               => "UTF-8",
	'utf8'                => "UTF-8",
	'x-unicode20utf8'     => "UTF-8",
	'866'                 => "IBM866",
	'cp866'               => "IBM866",
	'csibm866'            => "IBM866",
	'ibm866'              => "IBM866",
	'csisolatin2'         => "ISO-8859-2",
	'iso-8859-2'          => "ISO-8859-2",
	'iso-ir-101'          => "ISO-8859-2",
	'iso8859-2'           => "ISO-8859-2",
	'iso88592'            => "ISO-8859-2",
	'iso_8859-2'          => "ISO-8859-2",
	'iso_8859-2:1987'     => "ISO-8859-2",
	'l2'                  => "ISO-8859-2",
	'latin2'              => "ISO-8859-2",
	'csisolatin3'         => "ISO-8859-3",
	'iso-8859-3'          => "ISO-8859-3",
	'iso-ir-109'          => "ISO-8859-3",
	'iso8859-3'           => "ISO-8859-3",
	'iso88593'            => "ISO-8859-3",
	'iso_8859-3'          => "ISO-8859-3",
	'iso_8859-3:1988'     => "ISO-8859-3",
	'l3'                  => "ISO-8859-3",
	'latin3'              => "ISO-8859-3",
	'csisolatin4'         => "ISO-8859-4",
	'iso-8859-4'          => "ISO-8859-4",
	'iso-ir-110'          => "ISO-8859-4",
	'iso8859-4'           => "ISO-8859-4",
	'iso88594'            => "ISO-8859-4",
	'iso_8859-4'          => "ISO-8859-4",
	'iso_8859-4:1988'     => "ISO-8859-4",
	'l4'                  => "ISO-8859-4",
	'latin4'              => "ISO-8859-4",
	'csisolatincyrillic'  => "ISO-8859-5",
	'cyrillic'            => "ISO-8859-5",
	'iso-8859-5'          => "ISO-8859-5",
	'iso-ir-144'          => "ISO-8859-5",
	'iso8859-5'           => "ISO-8859-5",
	'iso88595'            => "ISO-8859-5",
	'iso_8859-5'          => "ISO-8859-5",
	'iso_8859-5:1988'     => "ISO-8859-5",
	'arabic'              => "ISO-8859-6",
	'asmo-708'            => "ISO-8859-6",
	'csiso88596e'         => "ISO-8859-6",
	'csiso88596i'         => "ISO-8859-6",
	'csisolatinarabic'    => "ISO-8859-6",
	'ecma-114'            => "ISO-8859-6",
	'iso-8859-6'          => "ISO-8859-6",
	'iso-8859-6-e'        => "ISO-8859-6",
	'iso-8859-6-i'        => "ISO-8859-6",
	'iso-ir-127'          => "ISO-8859-6",
	'iso8859-6'           => "ISO-8859-6",
	'iso88596'            => "ISO-8859-6",
	'iso_8859-6'          => "ISO-8859-6",
	'iso_8859-6:1987'     => "ISO-8859-6",
	'csisolatingreek'     => "ISO-8859-7",
	'ecma-118'            => "ISO-8859-7",
	'elot_928'            => "ISO-8859-7",
	'greek'               => "ISO-8859-7",
	'greek8'              => "ISO-8859-7",
	'iso-8859-7'          => "ISO-8859-7",
	'iso-ir-126'          => "ISO-8859-7",
	'iso8859-7'           => "ISO-8859-7",
	'iso88597'            => "ISO-8859-7",
	'iso_8859-7'          => "ISO-8859-7",
	'iso_8859-7:1987'     => "ISO-8859-7",
	'sun_eu_greek'        => "ISO-8859-7",
	'csiso88598e'         => "ISO-8859-8",
	'csisolatinhebrew'    => "ISO-8859-8",
	'hebrew'              => "ISO-8859-8",
	'iso-8859-8'          => "ISO-8859-8",
	'iso-8859-8-e'        => "ISO-8859-8",
	'iso-ir-138'          => "ISO-8859-8",
	'iso8859-8'           => "ISO-8859-8",
	'iso88598'            => "ISO-8859-8",
	'iso_8859-8'          => "ISO-8859-8",
	'iso_8859-8:1988'     => "ISO-8859-8",
	'visual'              => "ISO-8859-8",
	'csiso88598i'         => "ISO-8859-8-I",
	'iso-8859-8-i'        => "ISO-8859-8-I",
	'logical'             => "ISO-8859-8-I",
	'csisolatin6'         => "ISO-8859-10",
	'iso-8859-10'         => "ISO-8859-10",
	'iso-ir-157'          => "ISO-8859-10",
	'iso8859-10'          => "ISO-8859-10",
	'iso885910'           => "ISO-8859-10",
	'l6'                  => "ISO-8859-10",
	'latin6'              => "ISO-8859-10",
	'iso-8859-13'         => "ISO-8859-13",
	'iso8859-13'          => "ISO-8859-13",
	'iso885913'           => "ISO-8859-13",
	'iso-8859-14'         => "ISO-8859-14",
	'iso8859-14'          => "ISO-8859-14",
	'iso885914'           => "ISO-8859-14",
	'csisolatin9'         => "ISO-8859-15",
	'iso-8859-15'         => "ISO-8859-15",
	'iso8859-15'          => "ISO-8859-15",
	'iso885915'           => "ISO-8859-15",
	'iso_8859-15'         => "ISO-8859-15",
	'l9'                  => "ISO-8859-15",
	'iso-8859-16'         => "ISO-8859-16",
	'cskoi8r'             => "KOI8-R",
	'koi'                 => "KOI8-R",
	'koi8'                => "KOI8-R",
	'koi8-r'              => "KOI8-R",
	'koi8_r'              => "KOI8-R",
	'koi8-ru'             => "KOI8-U",
	'koi8-u'              => "KOI8-U",
	'csmacintosh'         => "macintosh",
	'mac'                 => "macintosh",
	'macintosh'           => "macintosh",
	'x-mac-roman'         => "macintosh",
	'dos-874'             => "windows-874",
	'iso-8859-11'         => "windows-874",
	'iso8859-11'          => "windows-874",
	'iso885911'           => "windows-874",
	'tis-620'             => "windows-874",
	'windows-874'         => "windows-874",
	'cp1250'              => "windows-1250",
	'windows-1250'        => "windows-1250",
	'x-cp1250'            => "windows-1250",
	'cp1251'              => "windows-1251",
	'windows-1251'        => "windows-1251",
	'x-cp1251'            => "windows-1251",
	'ansi_x3.4-1968'      => "windows-1252",
	'ascii'               => "windows-1252",
	'cp1252'              => "windows-1252",
	'cp819'               => "windows-1252",
	'csisolatin1'         => "windows-1252",
	'ibm819'              => "windows-1252",
	'iso-8859-1'          => "windows-1252",
	'iso-ir-100'          => "windows-1252",
	'iso8859-1'           => "windows-1252",
	'iso88591'            => "windows-1252",
	'iso_8859-1'          => "windows-1252",
	'iso_8859-1:1987'     => "windows-1252",
	'l1'                  => "windows-1252",
	'latin1'              => "windows-1252",
	'us-ascii'            => "windows-1252",
	'windows-1252'        => "windows-1252",
	'x-cp1252'            => "windows-1252",
	'cp1253'              => "windows-1253",
	'windows-1253'        => "windows-1253",
	'x-cp1253'            => "windows-1253",
	'cp1254'              => "windows-1254",
	'csisolatin5'         => "windows-1254",
	'iso-8859-9'          => "windows-1254",
	'iso-ir-148'          => "windows-1254",
	'iso8859-9'           => "windows-1254",
	'iso88599'            => "windows-1254",
	'iso_8859-9'          => "windows-1254",
	'iso_8859-9:1989'     => "windows-1254",
	'l5'                  => "windows-1254",
	'latin5'              => "windows-1254",
	'windows-1254'        => "windows-1254",
	'x-cp1254'            => "windows-1254",
	'cp1255'              => "windows-1255",
	'windows-1255'        => "windows-1255",
	'x-cp1255'            => "windows-1255",
	'cp1256'              => "windows-1256",
	'windows-1256'        => "windows-1256",
	'x-cp1256'            => "windows-1256",
	'cp1257'              => "windows-1257",
	'windows-1257'        => "windows-1257",
	'x-cp1257'            => "windows-1257",
	'cp1258'              => "windows-1258",
	'windows-1258'        => "windows-1258",
	'x-cp1258'            => "windows-1258",
	'x-mac-cyrillic'      => "x-mac-cyrillic",
	'x-mac-ukrainian'     => "x-mac-cyrillic",
	'chinese'             => "GBK",
	'csgb2312'            => "GBK",
	'csiso58gb231280'     => "GBK",
	'gb2312'              => "GBK",
	'gb_2312'             => "GBK",
	'gb_2312-80'          => "GBK",
	'gbk'                 => "GBK",
	'iso-ir-58'           => "GBK",
	'x-gbk'               => "GBK",
	'gb18030'             => "gb18030",
	'big5'                => "Big5",
	'big5-hkscs'          => "Big5",
	'cn-big5'             => "Big5",
	'csbig5'              => "Big5",
	'x-x-big5'            => "Big5",
	'cseucpkdfmtjapanese' => "EUC-JP",
	'euc-jp'              => "EUC-JP",
	'x-euc-jp'            => "EUC-JP",
	'csiso2022jp'         => "ISO-2022-JP",
	'iso-2022-jp'         => "ISO-2022-JP",
	'csshiftjis'          => "Shift_JIS",
	'ms932'               => "Shift_JIS",
	'ms_kanji'            => "Shift_JIS",
	'shift-jis'           => "Shift_JIS",
	'shift_jis'           => "Shift_JIS",
	'sjis'                => "Shift_JIS",
	'windows-31j'         => "Shift_JIS",
	'x-sjis'              => "Shift_JIS",
	'cseuckr'             => "EUC-KR",
	'csksc56011987'       => "EUC-KR",
	'euc-kr'              => "EUC-KR",
	'iso-ir-149'          => "EUC-KR",
	'korean'              => "EUC-KR",
	'ks_c_5601-1987'      => "EUC-KR",
	'ks_c_5601-1989'      => "EUC-KR",
	'ksc5601'             => "EUC-KR",
	'ksc_5601'            => "EUC-KR",
	'windows-949'         => "EUC-KR",
	'unicodefffe'         => "UTF-16BE",
	'utf-16be'            => "UTF-16BE",
	'csunicode'           => "UTF-16LE",
	'iso-10646-ucs-2'     => "UTF-16LE",
	'ucs-2'               => "UTF-16LE",
	'unicode'             => "UTF-16LE",
	'unicodefeff'         => "UTF-16LE",
	'utf-16'              => "UTF-16LE",
	'utf-16le'            => "UTF-16LE",
	'x-user-defined'      => "x-user-defined",
];
// test byte patterns and their UTF-8 equivalents; the test bytes all constitute a single character in the given encoding; all examples would yield different characters in ISO 8859-1 encoding (DOMDocument's default encoding) 
$encodings = [
    'UTF-8'          => ["\xC3\xA9",                     "\xC3\xA9"],
    'IBM866'         => ["\x86",                         "\xD0\x96"],
    'ISO-8859-2'     => ["\xD0",                         "\xC4\x90"],
    'ISO-8859-3'     => ["\xA1",                         "\xC4\xA6"],
    'ISO-8859-4'     => ["\xF9",                         "\xC5\xB3"],
    'ISO-8859-5'     => ["\xA4",                         "\xD0\x84"],
    'ISO-8859-6'     => ["\xEA",                         "\xD9\x8A"],
    'ISO-8859-7'     => ["\xBF",                         "\xCE\x8F"],
    'ISO-8859-8'     => ["\xAA",                         "\xC3\x97"],
    'ISO-8859-8-I'   => ["\xAA",                         "\xC3\x97"],
    'ISO-8859-10'    => ["\xA9",                         "\xC4\x90"],
    'ISO-8859-13'    => ["\xD9",                         "\xC5\x81"],
    'ISO-8859-14'    => ["\xD0",                         "\xC5\xB4"],
    'ISO-8859-15'    => ["\xBC",                         "\xC5\x92"],
    'ISO-8859-16'    => ["\xB2",                         "\xC4\x8C"],
    'KOI8-R'         => ["\xA7",                         "\xE2\x95\x96"],
    'KOI8-U'         => ["\xA7",                         "\xD1\x97"],
    'macintosh'      => ["\xA0",                         "\xE2\x80\xA0"],
    'windows-874'    => ["\x95",                         "\xE2\x80\xA2"],
    'windows-1250'   => ["\xBC",                         "\xC4\xBD"],
    'windows-1251'   => ["\xFF",                         "\xD1\x8F"],
    'windows-1252'   => ["\x9F",                         "\xC5\xB8"],
    'windows-1253'   => ["\x85",                         "\xE2\x80\xA6"],
    'windows-1254'   => ["\xDE",                         "\xC5\x9E"],
    'windows-1255'   => ["\x89",                         "\xE2\x80\xB0"],
    'windows-1256'   => ["\x8A",                         "\xD9\xB9"],
    'windows-1257'   => ["\x8F",                         "\xC2\xB8"],
    'windows-1258'   => ["\xDD",                         "\xC6\xAF"],
    'x-mac-cyrillic' => ["\xB0",                         "\xE2\x88\x9E"],
    'GBK'            => ["\x80",                         "\xE2\x82\xAC"],
    'gb18030'        => ["\xA2\xE3",                     "\xE2\x82\xAC"],
    'Big5'           => ["\xC6\xE2",                     "\xE3\x80\x87"],
    'EUC-JP'         => ["\xA1\xDD",                     "\xE2\x88\x92"],
    'ISO-2022-JP'    => ["\x1B\x28\x4A\x7E\x1B\x28\x42", "\xE2\x80\xBE"],
    'Shift_JIS'      => ["\x7E",                         "\xE2\x80\xBE"],
    'EUC-KR'         => ["\x81\xE9",                     "\xEA\xB3\xB2"],
    'UTF-16BE'       => ["\xD8\x34\xDD\x1E",             "\xF0\x9D\x84\x9E"],
    'UTF-16LE'       => ["\x34\xD8\x1E\xDD",             "\xF0\x9D\x84\x9E"],
	'x-user-defined' => ["\x80",                         "\xEF\x9E\x80"]
];

foreach ($labels as $label => $encoding) {
    list($input, $exp) = $encodings[$encoding];
    if ($encoding === "UTF-16BE") {
        $hint = "\xFE\xFF";
    } elseif ($encoding === "UTF-16LE") {
        $hint = "\xFF\xFE";
    } else {
        $hint = '<meta http-equiv="content-type" content="text/html;charset='.$label.'">';
    }
    $d = new DOMDocument;
    @$d->loadHTML($hint.$input);
    if (!$d->documentElement || $d->documentElement->textContent !== $exp) {
        echo "$label\n";
    }
}