MimeAnalyzer.php

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<?php
namespace Wikimedia\Mime;
 
use Psr\Log\LoggerAwareInterface;
use Psr\Log\LoggerInterface;
use Psr\Log\NullLogger;
use UnexpectedValueException;
 
class MimeAnalyzer implements LoggerAwareInterface {
 
    public const USE_INTERNAL = 'internal';
 
    private const MAGIC_NUMBERS = [
        // Multimedia...
        'MThd'             => 'audio/midi',
        'OggS'             => 'application/ogg',
        'ID3'              => 'audio/mpeg',
        "\xff\xfb"         => 'audio/mpeg', // MPEG-1 layer 3
        "\xff\xf3"         => 'audio/mpeg', // MPEG-2 layer 3 (lower sample rates)
        "\xff\xe3"         => 'audio/mpeg', // MPEG-2.5 layer 3 (very low sample rates)
 
        // Image formats...
        // Note that WMF may have a bare header, no magic number.
        "\x01\x00\x09\x00" => 'application/x-msmetafile', // Possibly prone to false positives?
        "\xd7\xcd\xc6\x9a" => 'application/x-msmetafile',
        '%PDF'             => 'application/pdf',
        'gimp xcf'         => 'image/x-xcf',
        "\xff\x0a"         => 'image/jxl',
        "\x00\x00\x00\x0C\x4A\x58\x4C\x20\x0D\x0A\x87\x0A" => 'image/jxl',
 
        // 3D
        'glTF'             => 'model/gltf-binary',
 
        // archive
        "PK\x03\x04"       => 'application/epub+zip',
 
        // Some forbidden fruit...
        'MZ'               => 'application/octet-stream', // DOS/Windows executable
        "\xca\xfe\xba\xbe" => 'application/octet-stream', // Mach-O binary
        "\x7fELF"          => 'application/octet-stream', // ELF binary
    ];
 
    private const RECOGNIZABLE_EXTENSIONS = [
        // Types recognized by getimagesize()
        'gif' => true,
        'jpeg' => true,
        'jpg' => true,
        'png' => true,
        'swf' => true,
        'psd' => true,
        'bmp' => true,
        'tiff' => true,
        'tif' => true,
        'jpc' => true,
        'jp2' => true,
        'jpx' => true,
        'jb2' => true,
        'swc' => true,
        'iff' => true,
        'wbmp' => true,
        'xbm' => true,
 
        // Formats we recognize magic numbers for
        'djvu' => true,
        'ogx' => true,
        'ogg' => true,
        'ogv' => true,
        'oga' => true,
        'spx' => true,
        'opus' => true,
        'mid' => true,
        'pdf' => true,
        'wmf' => true,
        'xcf' => true,
        'webm' => true,
        'mkv' => true,
        'mka' => true,
        'webp' => true,
        'mp3' => true,
        'jxl' => true,
 
        // XML formats we sure hope we recognize reliably
        'svg' => true,
 
        // 3D formats
        'stl' => true,
        'glb' => true,
    ];
 
    private const MAJOR_MIME_TYPES = [
        // See the definition of the `img_major_mime` enum in tables-generated.sql
        'unknown' => true,
        'application' => true,
        'audio' => true,
        'image' => true,
        'text' => true,
        'video' => true,
        'message' => true,
        'model' => true,
        'multipart' => true,
        'chemical' => true,
    ];
 
    private const PACK_MASKS = [
        'UTF-16BE' => 'n*',
        'UTF-16LE' => 'v*',
    ];
 
    protected $typeFile;
    protected $infoFile;
    protected $xmlTypes;
    protected $initCallback;
    protected $detectCallback;
    protected $guessCallback;
    protected $extCallback;
    protected $mediaTypes = null;
    protected $mimeTypeAliases = null;
    protected $mimeToExts = [];
    protected $extToMimes = [];
 
    public $mExtToMime = []; // legacy name; field accessed by hooks
 
    private $extraTypes = '';
    private $extraInfo = '';
 
    private $logger;
 
    public function __construct( array $params ) {
        $this->typeFile = $params['typeFile'];
        $this->infoFile = $params['infoFile'];
        $this->xmlTypes = $params['xmlTypes'];
        $this->initCallback = $params['initCallback'] ?? null;
        $this->detectCallback = $params['detectCallback'] ?? null;
        $this->guessCallback = $params['guessCallback'] ?? null;
        $this->extCallback = $params['extCallback'] ?? null;
        $this->logger = $params['logger'] ?? new NullLogger();
 
        $this->loadFiles();
    }
 
    protected function loadFiles(): void {
        # Allow media handling extensions adding MIME-types and MIME-info
        if ( $this->initCallback ) {
            ( $this->initCallback )( $this );
        }
 
        $rawTypes = $this->extraTypes;
        if ( $this->typeFile === self::USE_INTERNAL ) {
            $this->mimeToExts = MimeMap::MIME_EXTENSIONS;
        } else {
            $this->mimeToExts = MimeMapMinimal::MIME_EXTENSIONS;
            if ( $this->typeFile ) {
                $rawTypes = file_get_contents( $this->typeFile ) . "\n" . $this->extraTypes;
            }
        }
        if ( $rawTypes ) {
            $this->parseMimeTypes( $rawTypes );
        }
 
        // Build the reverse mapping (extension => MIME type).
        foreach ( $this->mimeToExts as $mime => $exts ) {
            foreach ( $exts as $ext ) {
                $this->extToMimes[$ext][] = $mime;
            }
        }
 
        // Migrate items from the legacy $this->mExtToMime field.
        // TODO: Remove this when mExtToMime is finally removed.
        foreach ( $this->mExtToMime as $ext => $mimes ) {
            foreach ( explode( ' ', $mimes ) as $mime ) {
                $this->extToMimes[$ext][] = $mime;
            }
        }
 
        $rawInfo = $this->extraInfo;
        if ( $this->infoFile === self::USE_INTERNAL ) {
            $this->mimeTypeAliases = MimeMap::MIME_TYPE_ALIASES;
            $this->mediaTypes = MimeMap::MEDIA_TYPES;
        } else {
            $this->mimeTypeAliases = MimeMapMinimal::MIME_TYPE_ALIASES;
            $this->mediaTypes = MimeMapMinimal::MEDIA_TYPES;
            if ( $this->infoFile ) {
                $rawInfo = file_get_contents( $this->infoFile ) . "\n" . $this->extraInfo;
            }
        }
        if ( $rawInfo ) {
            $this->parseMimeInfo( $rawInfo );
        }
    }
 
    protected function parseMimeTypes( string $rawMimeTypes ): void {
        $rawMimeTypes = str_replace( [ "\r\n", "\n\r", "\n\n", "\r\r", "\r" ], "\n", $rawMimeTypes );
        $rawMimeTypes = str_replace( "\t", " ", $rawMimeTypes );
 
        $lines = explode( "\n", $rawMimeTypes );
        foreach ( $lines as $s ) {
            $s = trim( $s );
            if ( $s === '' || str_starts_with( $s, '#' ) ) {
                continue;
            }
 
            $s = strtolower( $s );
            $i = strpos( $s, ' ' );
 
            if ( $i === false ) {
                continue;
            }
 
            $ext = trim( substr( $s, $i + 1 ) );
 
            if ( !$ext ) {
                continue;
            }
 
            $tokens = preg_split( '/\s+/', $s, -1, PREG_SPLIT_NO_EMPTY );
            if ( count( $tokens ) > 1 ) {
                $mime = array_shift( $tokens );
                $this->mimeToExts[$mime] = array_values( array_unique(
                    array_merge( $this->mimeToExts[$mime] ?? [], $tokens ) ) );
            }
        }
    }
 
    protected function parseMimeInfo( string $rawMimeInfo ): void {
        $rawMimeInfo = str_replace( [ "\r\n", "\n\r", "\n\n", "\r\r", "\r" ], "\n", $rawMimeInfo );
        $rawMimeInfo = str_replace( "\t", " ", $rawMimeInfo );
 
        $lines = explode( "\n", $rawMimeInfo );
        foreach ( $lines as $s ) {
            $s = trim( $s );
            if ( $s === '' || str_starts_with( $s, '#' ) ) {
                continue;
            }
 
            $s = strtolower( $s );
            $i = strpos( $s, ' ' );
 
            if ( $i === false ) {
                continue;
            }
 
            # print "processing MIME INFO line $s<br>";
 
            $match = [];
            if ( preg_match( '!\[\s*(\w+)\s*\]!', $s, $match ) ) {
                $s = preg_replace( '!\[\s*(\w+)\s*\]!', '', $s );
                $mtype = trim( strtoupper( $match[1] ) );
            } else {
                $mtype = MEDIATYPE_UNKNOWN;
            }
 
            $m = preg_split( '/\s+/', $s, -1, PREG_SPLIT_NO_EMPTY );
 
            if ( !isset( $this->mediaTypes[$mtype] ) ) {
                $this->mediaTypes[$mtype] = [];
            }
 
            foreach ( $m as $mime ) {
                $mime = trim( $mime );
                if ( !$mime ) {
                    continue;
                }
 
                $this->mediaTypes[$mtype][] = $mime;
            }
 
            if ( count( $m ) > 1 ) {
                $main = $m[0];
                $mCount = count( $m );
                for ( $i = 1; $i < $mCount; $i += 1 ) {
                    $mime = $m[$i];
                    $this->mimeTypeAliases[$mime] = $main;
                }
            }
        }
    }
 
    public function setLogger( LoggerInterface $logger ): void {
        $this->logger = $logger;
    }
 
    public function addExtraTypes( string $types ): void {
        $this->extraTypes .= "\n" . $types;
    }
 
    public function addExtraInfo( string $info ): void {
        $this->extraInfo .= "\n" . $info;
    }
 
    public function getExtensionsForType( $mime ) {
        $exts = $this->getExtensionsFromMimeType( $mime );
        return $exts ? implode( ' ', $exts ) : null;
    }
 
    public function getExtensionsFromMimeType( string $mime ): array {
        $mime = strtolower( $mime );
        if ( !isset( $this->mimeToExts[$mime] ) && isset( $this->mimeTypeAliases[$mime] ) ) {
            $mime = $this->mimeTypeAliases[$mime];
        }
        return $this->mimeToExts[$mime] ?? [];
    }
 
    public function getMimeTypesFromExtension( string $ext ): array {
        $ext = strtolower( $ext );
        return $this->extToMimes[$ext] ?? [];
    }
 
    public function getMimeTypeFromExtensionOrNull( string $ext ): ?string {
        $types = $this->getMimeTypesFromExtension( $ext );
        return $types[0] ?? null;
    }
 
    public function guessTypesForExtension( $ext ) {
        return $this->getMimeTypeFromExtensionOrNull( $ext );
    }
 
    public function getTypesForExtension( $ext ) {
        $types = $this->getMimeTypesFromExtension( $ext );
        return $types ? implode( ' ', $types ) : null;
    }
 
    public function getExtensionFromMimeTypeOrNull( string $mime ): ?string {
        $exts = $this->getExtensionsFromMimeType( $mime );
        return $exts[0] ?? null;
    }
 
    public function isMatchingExtension( string $extension, string $mime ): ?bool {
        $exts = $this->getExtensionsFromMimeType( $mime );
 
        if ( !$exts ) {
            return null; // Unknown MIME type
        }
 
        return in_array( strtolower( $extension ), $exts );
    }
 
    public function isRecognizableExtension( string $extension ): bool {
        return isset( self::RECOGNIZABLE_EXTENSIONS[strtolower( $extension )] );
    }
 
    public function improveTypeFromExtension( string $mime, string $ext ): ?string {
        if ( $mime === 'unknown/unknown' ) {
            if ( $this->isRecognizableExtension( $ext ) ) {
                $this->logger->info( __METHOD__ . ': refusing to guess mime type for .' .
                    "$ext file, we should have recognized it" );
            } else {
                // Not something we can detect, so simply
                // trust the file extension
                $mime = $this->getMimeTypeFromExtensionOrNull( $ext );
            }
        } elseif ( $mime === 'application/x-opc+zip'
            || $mime === 'application/vnd.oasis.opendocument'
        ) {
            if ( $this->isMatchingExtension( $ext, $mime ) ) {
                // A known file extension for an OPC/ODF file,
                // find the proper MIME type for that file extension
                $mime = $this->getMimeTypeFromExtensionOrNull( $ext );
            } else {
                $this->logger->info( __METHOD__ .
                    ": refusing to guess better type for $mime file, " .
                    ".$ext is not a known OPC/ODF extension." );
                $mime = 'application/zip';
            }
        } elseif ( $mime === 'text/plain' && $this->findMediaType( ".$ext" ) === MEDIATYPE_TEXT ) {
            // Textual types are sometimes not recognized properly.
            // If detected as text/plain, and has an extension which is textual
            // improve to the extension's type. For example, csv and json are often
            // misdetected as text/plain.
            $mime = $this->getMimeTypeFromExtensionOrNull( $ext );
        }
 
        # Media handling extensions can improve the MIME detected
        $callback = $this->extCallback;
        if ( $callback ) {
            $callback( $this, $ext, $mime /* by reference */ );
        }
 
        if ( $mime !== null && isset( $this->mimeTypeAliases[$mime] ) ) {
            $mime = $this->mimeTypeAliases[$mime];
        }
 
        $this->logger->info( __METHOD__ . ": improved mime type for .$ext: $mime" );
        return $mime;
    }
 
    public function guessMimeType( string $file, $ext = true ): string {
        if ( $ext ) { // TODO: make $ext default to false. Or better, remove it.
            $this->logger->info( __METHOD__ .
                ": WARNING: use of the \$ext parameter is deprecated. " .
                "Use improveTypeFromExtension(\$mime, \$ext) instead." );
        }
 
        $mime = $this->doGuessMimeType( $file );
 
        if ( !$mime ) {
            $this->logger->info( __METHOD__ .
                ": internal type detection failed for $file (.$ext)..." );
            $mime = $this->detectMimeType( $file, $ext );
        }
 
        if ( isset( $this->mimeTypeAliases[$mime] ) ) {
            $mime = $this->mimeTypeAliases[$mime];
        }
 
        $this->logger->info( __METHOD__ . ": guessed mime type of $file: $mime" );
        return $mime;
    }
 
    private function doGuessMimeType( string $file ) {
        // Read a chunk of the file
        // phpcs:ignore Generic.PHP.NoSilencedErrors.Discouraged
        $f = @fopen( $file, 'rb' );
 
        if ( !$f ) {
            return 'unknown/unknown';
        }
 
        $fsize = filesize( $file );
        if ( $fsize === false ) {
            return 'unknown/unknown';
        }
 
        $head = fread( $f, 1024 );
        $head16k = $head . fread( $f, 16384 - 1024 ); // some WebM files have big headers
        $tailLength = min( 65558, $fsize ); // 65558 = maximum size of a zip EOCDR
        if ( fseek( $f, -1 * $tailLength, SEEK_END ) === -1 ) {
            throw new UnexpectedValueException(
                "Seeking $tailLength bytes from EOF failed in " . __METHOD__ );
        }
        $tail = $tailLength ? fread( $f, $tailLength ) : '';
 
        $this->logger->info( __METHOD__ .
            ": analyzing head and tail of $file for magic numbers." );
 
        // Hardcode a few magic number checks...
        foreach ( self::MAGIC_NUMBERS as $magic => $candidate ) {
            if ( str_starts_with( $head, $magic ) ) {
                $this->logger->info( __METHOD__ .
                    ": magic header in $file recognized as $candidate" );
                return $candidate;
            }
        }
 
        /* Look for WebM and Matroska files */
        if ( str_starts_with( $head16k, "\x1a\x45\xdf\xa3" ) ) {
            $doctype = strpos( $head16k, "\x42\x82" );
            if ( $doctype ) {
                // Next byte is datasize, then data (sizes larger than 1 byte are stupid muxers)
                $data = substr( $head16k, $doctype + 3, 8 );
                if ( str_starts_with( $data, "matroska" ) ) {
                    $this->logger->info( __METHOD__ . ": recognized file as video/matroska" );
                    return "video/matroska";
                }
 
                if ( str_starts_with( $data, "webm" ) ) {
                    // XXX HACK look for a video track, if we don't find it, this is an audio file
                    // This detection is very naive and doesn't parse the actual fields
                    // 0x86 byte indicates start of codecname field
                    // next byte is a variable length integer (vint) for the size of the value following it
                    // 8 (first bit is 1) indicates the smallest size vint, a single byte
                    // (unlikely we see larger vints here)
                    // 5 indicates a length of 5 ( V_VP8 or V_VP9 or V_AV1 )
                    // Sometimes we see 0x86 instead of 0x85 because a
                    // non-conforming muxer wrote a null terminated string
                    $videotrack = str_contains( $head16k, "\x86\x85V_VP8" ) ||
                        str_contains( $head16k, "\x86\x85V_VP9" ) ||
                        str_contains( $head16k, "\x86\x85V_AV1" ) ||
                        str_contains( $head16k, "\x86\x86V_VP8\x0" ) ||
                        str_contains( $head16k, "\x86\x86V_VP9\x0" ) ||
                        str_contains( $head16k, "\x86\x86V_AV1\x0" );
 
                    if ( $videotrack ) {
                        // There is a video track, so this is a video file.
                        $this->logger->info( __METHOD__ . ": recognized file as video/webm" );
                        return "video/webm";
                    }
 
                    $this->logger->info( __METHOD__ . ": recognized file as audio/webm" );
                    return "audio/webm";
                }
            }
            $this->logger->info( __METHOD__ . ": unknown EBML file" );
            return "unknown/unknown";
        }
 
        /* Look for WebP */
        if ( str_starts_with( $head, "RIFF" ) && substr( $head, 8, 7 ) === "WEBPVP8" ) {
            $this->logger->info( __METHOD__ . ": recognized file as image/webp" );
            return "image/webp";
        }
 
        /* Look for JPEG2000 */
        if ( str_starts_with( $head, "\x00\x00\x00\x0cjP\x20\x20\x0d\x0a\x87\x0a" ) ) {
            $this->logger->info( __METHOD__ . ": recognized as JPEG2000" );
            // we skip 4 bytes
            if ( substr( $head, 16, 8 ) === "ftypjp2 " ) {
                $this->logger->info( __METHOD__ . ": recognized file as image/jp2" );
                return 'image/jp2';
            } elseif ( substr( $head, 16, 8 ) === "ftypjpx " ) {
                $this->logger->info( __METHOD__ . ": recognized file as image/jpx" );
                return 'image/jpx';
            }
        }
 
        /* Look for MS Compound Binary (OLE) files */
        if ( str_starts_with( $head, "\xd0\xcf\x11\xe0\xa1\xb1\x1a\xe1" ) ) {
            $this->logger->info( __METHOD__ . ': recognized MS CFB (OLE) file' );
            return $this->detectMicrosoftBinaryType( $f );
        }
 
        if ( str_contains( $head, '<?php' ) ||
            str_contains( $head, "<\x00?\x00p\x00h\x00p" ) ||
            str_contains( $head, "<\x00?\x00 " ) ||
            str_contains( $head, "<\x00?\x00\n" ) ||
            str_contains( $head, "<\x00?\x00\t" ) ||
            str_contains( $head, "<\x00?\x00=" )
        ) {
            $this->logger->info( __METHOD__ . ": recognized $file as application/x-php" );
            return 'application/x-php';
        }
 
        // phpcs:ignore Generic.PHP.NoSilencedErrors.Discouraged
        $xml = @new XmlTypeCheck( $file );
        if ( $xml->wellFormed ) {
            $xmlTypes = $this->xmlTypes;
            // @phan-suppress-next-line PhanTypeMismatchDimFetch False positive
            return $xmlTypes[$xml->getRootElement()] ?? 'application/xml';
        }
 
        $script_type = null;
 
        # detect by shebang
        if ( str_starts_with( $head, "#!" ) ) {
            $script_type = "ASCII";
        } elseif ( str_starts_with( $head, "\xef\xbb\xbf#!" ) ) {
            $script_type = "UTF-8";
        } elseif ( str_starts_with( $head, "\xfe\xff\x00#\x00!" ) ) {
            $script_type = "UTF-16BE";
        } elseif ( str_starts_with( $head, "\xff\xfe#\x00!" ) ) {
            $script_type = "UTF-16LE";
        }
 
        if ( $script_type ) {
            if ( $script_type !== "UTF-8" && $script_type !== "ASCII" ) {
                // Quick and dirty fold down to ASCII!
                $chars = unpack( self::PACK_MASKS[$script_type], substr( $head, 2 ) );
                $head = '';
                foreach ( $chars as $codepoint ) {
                    if ( $codepoint < 128 ) {
                        $head .= chr( $codepoint );
                    } else {
                        $head .= '?';
                    }
                }
            }
 
            $match = [];
 
            if ( preg_match( '%/?([^\s]+/)(\w+)%', $head, $match ) ) {
                $mime = "application/x-{$match[2]}";
                $this->logger->info( __METHOD__ . ": shell script recognized as $mime" );
                return $mime;
            }
        }
 
        // Check for ZIP variants (before getimagesize)
        $eocdrPos = strpos( $tail, "PK\x05\x06" );
        if ( $eocdrPos !== false && $eocdrPos <= strlen( $tail ) - 22 ) {
            $this->logger->info( __METHOD__ . ": ZIP signature present in $file" );
            // Check if it really is a ZIP file, make sure the EOCDR is at the end (T40432)
            $commentLength = unpack( "n", substr( $tail, $eocdrPos + 20 ) )[1];
            if ( $eocdrPos + 22 + $commentLength !== strlen( $tail ) ) {
                $this->logger->info( __METHOD__ . ": ZIP EOCDR not at end. Not a ZIP file." );
            } else {
                return $this->detectZipTypeFromFile( $f );
            }
        }
 
        // Check for STL (3D) files
        // @see https://en.wikipedia.org/wiki/STL_(file_format)
        if ( $fsize >= 15 &&
            stripos( $head, 'SOLID ' ) === 0 &&
            preg_match( '/\RENDSOLID .*$/i', $tail ) ) {
            // ASCII STL file
            return 'application/sla';
        } elseif ( $fsize > 84 ) {
            // binary STL file
            $triangles = substr( $head, 80, 4 );
            $triangles = unpack( 'V', $triangles );
            $triangles = reset( $triangles );
            if ( $triangles !== false && $fsize === 84 + ( $triangles * 50 ) ) {
                return 'application/sla';
            }
        }
 
        // phpcs:ignore Generic.PHP.NoSilencedErrors.Discouraged
        $gis = @getimagesize( $file );
 
        if ( $gis && isset( $gis['mime'] ) ) {
            $mime = $gis['mime'];
            $this->logger->info( __METHOD__ . ": getimagesize detected $file as $mime" );
            return $mime;
        }
 
        # Media handling extensions can guess the MIME by content
        # It's intentionally here so that if core is wrong about a type (false positive),
        # people will hopefully nag and submit patches :)
        $mime = false;
        # Some strings by reference for performance - assuming well-behaved hooks
        $callback = $this->guessCallback;
        if ( $callback ) {
            $callback( $this, $head, $tail, $file, $mime /* by reference */ );
        }
 
        return $mime;
    }
 
    public function detectZipTypeFromFile( $handle ) {
        $types = [];
        $status = ZipDirectoryReader::readHandle(
            $handle,
            static function ( $entry ) use ( &$types ) {
                $name = $entry['name'];
                $names = [ $name ];
 
                // If there is a null character, cut off the name at it, because JDK's
                // ZIP_GetEntry() uses strcmp() if the name hashes match. If a file name
                // were constructed which had ".class\0" followed by a string chosen to
                // make the hash collide with the truncated name, that file could be
                // returned in response to a request for the .class file.
                $nullPos = strpos( $entry['name'], "\000" );
                if ( $nullPos !== false ) {
                    $names[] = substr( $entry['name'], 0, $nullPos );
                }
 
                // If there is a trailing slash in the file name, we have to strip it,
                // because that's what ZIP_GetEntry() does.
                if ( preg_grep( '!\.class/?$!', $names ) ) {
                    $types[] = 'application/java';
                }
 
                if ( $name === '[Content_Types].xml' ) {
                    $types[] = 'application/x-opc+zip';
                } elseif ( $name === 'mimetype' ) {
                    $types[] = 'application/vnd.oasis.opendocument';
                }
            }
        );
        if ( !$status->isOK() ) {
            $this->logger->info( "Error reading zip file: " . (string)$status );
            // This could be unknown/unknown but we have some weird phpunit test cases
            return 'application/zip';
        }
        if ( in_array( 'application/java', $types ) ) {
            // For security, java detection takes precedence
            return 'application/java';
        } elseif ( count( $types ) ) {
            return $types[0];
        } else {
            return 'application/zip';
        }
    }
 
    private function detectMicrosoftBinaryType( $handle ): string {
        $info = MSCompoundFileReader::readHandle( $handle );
        if ( !$info['valid'] ) {
            $this->logger->info( __METHOD__ . ': invalid file format' );
            return 'unknown/unknown';
        }
        if ( !$info['mime'] ) {
            $this->logger->info( __METHOD__ . ": unrecognised document subtype" );
            return 'unknown/unknown';
        }
        return $info['mime'];
    }
 
    private function detectMimeType( string $file, $ext = true ): string {
        if ( $ext ) {
            $this->logger->info( __METHOD__ .
                ": WARNING: use of the \$ext parameter is deprecated. "
                . "Use improveTypeFromExtension(\$mime, \$ext) instead." );
        }
 
        $callback = $this->detectCallback;
        if ( $callback ) {
            $m = $callback( $file );
        } else {
            $m = mime_content_type( $file );
        }
 
        if ( $m ) {
            # normalize
            $m = preg_replace( '![;, ].*$!', '', $m ); # strip charset, etc
            $m = trim( $m );
            $m = strtolower( $m );
 
            if ( !str_contains( $m, 'unknown' ) ) {
                $this->logger->info( __METHOD__ . ": magic mime type of $file: $m" );
                return $m;
            }
        }
 
        // If desired, look at extension as a fallback.
        if ( $ext === true ) {
            $i = strrpos( $file, '.' );
            $ext = strtolower( $i ? substr( $file, $i + 1 ) : '' );
        }
        if ( $ext ) {
            if ( $this->isRecognizableExtension( $ext ) ) {
                $this->logger->info( __METHOD__ . ": refusing to guess mime type for .$ext file, "
                    . "we should have recognized it" );
            } else {
                $m = $this->getMimeTypeFromExtensionOrNull( $ext );
                if ( $m ) {
                    $this->logger->info( __METHOD__ . ": extension mime type of $file: $m" );
                    return $m;
                }
            }
        }
 
        // Unknown type
        $this->logger->info( __METHOD__ . ": failed to guess mime type for $file!" );
        return 'unknown/unknown';
    }
 
    public function getMediaType( ?string $path = null, ?string $mime = null ): string {
        if ( !$mime && !$path ) {
            return MEDIATYPE_UNKNOWN;
        }
 
        // If MIME type is unknown, guess it
        if ( !$mime ) {
            // @phan-suppress-next-line PhanTypeMismatchArgumentNullable False positive
            $mime = $this->guessMimeType( $path, false );
        }
 
        // Special code for ogg - detect if it's video (theora),
        // else label it as sound.
        if ( $mime == 'application/ogg' && is_string( $path ) && file_exists( $path ) ) {
            // Read a chunk of the file
            $f = fopen( $path, "rt" );
            if ( !$f ) {
                return MEDIATYPE_UNKNOWN;
            }
            $head = fread( $f, 256 );
            fclose( $f );
 
            $head = str_replace( 'ffmpeg2theora', '', strtolower( $head ) );
 
            // This is an UGLY HACK, file should be parsed correctly
            if ( str_contains( $head, 'theora' ) ) {
                return MEDIATYPE_VIDEO;
            } elseif ( str_contains( $head, 'vorbis' ) ) {
                return MEDIATYPE_AUDIO;
            } elseif ( str_contains( $head, 'flac' ) ) {
                return MEDIATYPE_AUDIO;
            } elseif ( str_contains( $head, 'speex' ) ) {
                return MEDIATYPE_AUDIO;
            } elseif ( str_contains( $head, 'opus' ) ) {
                return MEDIATYPE_AUDIO;
            } else {
                return MEDIATYPE_MULTIMEDIA;
            }
        }
 
        $type = null;
        // Check for entry for full MIME type
        if ( $mime ) {
            $type = $this->findMediaType( $mime );
            if ( $type !== MEDIATYPE_UNKNOWN ) {
                return $type;
            }
        }
 
        // Check for entry for file extension
        if ( $path ) {
            $i = strrpos( $path, '.' );
            $e = strtolower( $i ? substr( $path, $i + 1 ) : '' );
 
            // TODO: look at multi-extension if this fails, parse from full path
            $type = $this->findMediaType( '.' . $e );
            if ( $type !== MEDIATYPE_UNKNOWN ) {
                return $type;
            }
        }
 
        // Check major MIME type
        if ( $mime ) {
            $i = strpos( $mime, '/' );
            if ( $i !== false ) {
                $major = substr( $mime, 0, $i );
                $type = $this->findMediaType( $major );
                if ( $type !== MEDIATYPE_UNKNOWN ) {
                    return $type;
                }
            }
        }
 
        if ( !$type ) {
            $type = MEDIATYPE_UNKNOWN;
        }
 
        return $type;
    }
 
    private function findMediaType( string $extMime ) {
        if ( str_starts_with( $extMime, '.' ) ) {
            // If it's an extension, look up the MIME types
            $m = $this->getMimeTypesFromExtension( substr( $extMime, 1 ) );
            if ( !$m ) {
                return MEDIATYPE_UNKNOWN;
            }
        } else {
            // Normalize MIME type
            if ( isset( $this->mimeTypeAliases[$extMime] ) ) {
                $extMime = $this->mimeTypeAliases[$extMime];
            }
 
            $m = [ $extMime ];
        }
 
        foreach ( $m as $mime ) {
            foreach ( $this->mediaTypes as $type => $codes ) {
                if ( in_array( $mime, $codes, true ) ) {
                    return $type;
                }
            }
        }
 
        return MEDIATYPE_UNKNOWN;
    }
 
    public function getMediaTypes(): array {
        return array_keys( $this->mediaTypes );
    }
 
    public function isValidMajorMimeType( string $type ): bool {
        return isset( self::MAJOR_MIME_TYPES[$type] );
    }
}
 
class_alias( MimeAnalyzer::class, 'MimeAnalyzer' );