wikimedia/mediawiki-core

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includes/media/MediaHandler.php

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<?php
/**
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 * http://www.gnu.org/copyleft/gpl.html
 *
 * @file
 */

use MediaWiki\Context\IContextSource;
use MediaWiki\HookContainer\HookRunner;
use MediaWiki\MediaWikiServices;
use MediaWiki\Parser\Parser;
use MediaWiki\Status\Status;

/**
 * @defgroup Media Media
 *
 * Media handlers and other classes relating to Multimedia support,
 * with the exception of FileRepo and FileBackend, which have their own groups.
 */

/**
 * Base media handler class
 *
 * @stable to extend
 * @ingroup Media
 */
abstract class MediaHandler {
    public const TRANSFORM_LATER = 1;
    public const METADATA_GOOD = true;
    public const METADATA_BAD = false;
    public const METADATA_COMPATIBLE = 2; // for old but backwards compatible.
    /**
     * Max length of error logged by logErrorForExternalProcess()
     */
    private const MAX_ERR_LOG_SIZE = 65535;

    /**
     * Get a MediaHandler for a given MIME type from the instance cache
     *
     * @param string $type
     * @return MediaHandler|false
     */
    public static function getHandler( $type ) {
        return MediaWikiServices::getInstance()
            ->getMediaHandlerFactory()->getHandler( $type );
    }

    /**
     * Get an associative array mapping magic word IDs to parameter names.
     * Will be used by the parser to identify parameters.
     * @return string[]
     */
    abstract public function getParamMap();

    /**
     * Validate a thumbnail parameter at parse time.
     * Return true to accept the parameter, and false to reject it.
     * If you return false, the parser will do something quiet and forgiving.
     *
     * @param string $name
     * @param mixed $value
     * @return bool
     */
    abstract public function validateParam( $name, $value );

    /**
     * Merge a parameter array into a string appropriate for inclusion in filenames
     *
     * @param array $params Array of parameters that have been through normaliseParams.
     * @return string
     */
    abstract public function makeParamString( $params );

    /**
     * Parse a param string made with makeParamString back into an array
     *
     * @param string $str The parameter string without file name (e.g. 122px)
     * @return array|false Array of parameters or false on failure.
     */
    abstract public function parseParamString( $str );

    /**
     * Changes the parameter array as necessary, ready for transformation.
     * Should be idempotent.
     * Returns false if the parameters are unacceptable and the transform should fail
     * @param File $image
     * @param array &$params
     * @return bool
     */
    abstract public function normaliseParams( $image, &$params );

    /**
     * Get an image size array like that returned by getimagesize(), or false if it
     * can't be determined.
     *
     * This function is used for determining the width, height and bitdepth directly
     * from an image. The results are stored in the database in the img_width,
     * img_height, img_bits fields.
     *
     * @note If this is a multipage file, return the width and height of the
     *  first page.
     *
     * @deprecated since 1.37, override getSizeAndMetadata instead
     *
     * @param File|FSFile|false $image The image object, or false if there isn't one.
     *   Warning, FSFile::getPropsFromPath might pass an FSFile instead of File (!)
     * @param string $path The filename
     * @return array|false Follow the format of PHP getimagesize() internal function.
     *   See https://www.php.net/getimagesize. MediaWiki will only ever use the
     *   first two array keys (the width and height), and the 'bits' associative
     *   key. All other array keys are ignored. Returning a 'bits' key is optional
     *   as not all formats have a notion of "bitdepth". Returns false on failure.
     */
    public function getImageSize( $image, $path ) {
        return false;
    }

    /**
     * Get image size information and metadata array.
     *
     * If this returns null, the caller will fall back to getImageSize() and
     * getMetadata().
     *
     * If getImageSize() or getMetadata() are implemented in the most derived
     * class, they will be used instead of this function. To override this
     * behaviour, override useLegacyMetadata().
     *
     * @stable to override
     * @since 1.37
     *
     * @param MediaHandlerState $state An object for saving process-local state.
     *   This is normally a File object which will be passed back to other
     *   MediaHandler methods like pageCount(), if they are called in the same
     *   request. The handler can use this object to save its state.
     * @param string $path The filename
     * @return array|null Null to fall back to getImageSize(), or an array with
     *   the following keys. All keys are optional.
     *     - width: The width. If multipage, return the first page width. (optional)
     *     - height: The height. If multipage, return the first page height. (optional)
     *     - bits: The number of bits for each color (optional)
     *     - metadata: A JSON-serializable array of metadata (optional)
     */
    public function getSizeAndMetadata( $state, $path ) {
        return null;
    }

    /**
     * Get handler-specific metadata which will be saved in the img_metadata field.
     * @deprecated since 1.37 override getSizeAndMetadata() instead
     *
     * @param File|FSFile|false $image The image object, or false if there isn't one.
     *   Warning, FSFile::getPropsFromPath might pass an FSFile instead of File (!)
     * @param string $path The filename
     * @return string A string of metadata in php serialized form (Run through serialize())
     */
    public function getMetadata( $image, $path ) {
        return '';
    }

    /**
     * If this returns true, the new method getSizeAndMetadata() will not be
     * called. The legacy methods getMetadata() and getImageSize() will be used
     * instead.
     *
     * @since 1.37
     * @stable to override
     * @return bool
     */
    protected function useLegacyMetadata() {
        return $this->hasMostDerivedMethod( 'getMetadata' )
            || $this->hasMostDerivedMethod( 'getImageSize' );
    }

    /**
     * Check whether a method is implemented in the most derived class.
     *
     * @since 1.37
     * @param string $name
     * @return bool
     */
    protected function hasMostDerivedMethod( $name ) {
        $rc = new ReflectionClass( $this );
        $rm = new ReflectionMethod( $this, $name );
        return $rm->getDeclaringClass()->getName() === $rc->getName();
    }

    /**
     * Get the metadata array and the image size, with b/c fallback.
     *
     * The legacy methods will be used if useLegacyMetadata() returns true or
     * if getSizeAndMetadata() returns null.
     *
     * Absent metadata will be normalized to an empty array. Absent width and
     * height will be normalized to zero.
     *
     * @param File|FSFile $file This must be a File or FSFile to support the
     *   legacy methods. When the legacy methods are removed, this will be
     *   narrowed to MediaHandlerState.
     * @param string $path
     * @return array|false|null False on failure, or an array with the following keys:
     *   - width: The width. If multipage, return the first page width.
     *   - height: The height. If multipage, return the first page height.
     *   - bits: The number of bits for each color (optional)
     *   - metadata: A JSON-serializable array of metadata
     * @since 1.37
     */
    final public function getSizeAndMetadataWithFallback( $file, $path ) {
        if ( !$this->useLegacyMetadata() ) {
            if ( $file instanceof MediaHandlerState ) {
                $state = $file;
            } else {
                $state = new TrivialMediaHandlerState;
            }
            $info = $this->getSizeAndMetadata( $state, $path );
            if ( $info === false ) {
                return false;
            }
            if ( $info !== null ) {
                $info += [ 'width' => 0, 'height' => 0, 'metadata' => [] ];
                if ( !is_array( $info['metadata'] ) ) {
                    throw new InvalidArgumentException( 'Media handler ' .
                        static::class . ' returned ' . get_debug_type( $info['metadata'] ) .
                        ' for metadata, should be array' );
                }
                return $info;
            }
        }

        $blob = $this->getMetadata( $file, $path );
        // @phan-suppress-next-line PhanParamTooMany
        $size = $this->getImageSize(
            $file,
            $path,
            $blob // Secret TimedMediaHandler parameter
        );
        if ( $blob === false && $size === false ) {
            return false;
        }
        if ( $size ) {
            $info = [
                'width' => $size[0] ?? 0,
                'height' => $size[1] ?? 0
            ];
            if ( isset( $size['bits'] ) ) {
                $info['bits'] = $size['bits'];
            }
        } else {
            $info = [ 'width' => 0, 'height' => 0 ];
        }
        if ( $blob !== false ) {
            // phpcs:ignore Generic.PHP.NoSilencedErrors.Discouraged
            $metadata = @unserialize( $blob );
            if ( $metadata === false ) {
                // Unserialize error
                $metadata = [ '_error' => $blob ];
            } elseif ( !is_array( $metadata ) ) {
                $metadata = [];
            }
            $info['metadata'] = $metadata;
        } else {
            $info['metadata'] = [];
        }
        return $info;
    }

    /**
     * Get metadata version.
     *
     * This is not used for validating metadata, this is used for the api when returning
     * metadata, since api content formats should stay the same over time, and so things
     * using ForeignApiRepo can keep backwards compatibility
     *
     * All core media handlers share a common version number, and extensions can
     * use the GetMetadataVersion hook to append to the array (they should append a unique
     * string so not to get confusing). If there was a media handler named 'foo' with metadata
     * version 3 it might add to the end of the array the element 'foo=3'. if the core metadata
     * version is 2, the end version string would look like '2;foo=3'.
     *
     * @stable to override
     *
     * @return string Version string
     */
    public static function getMetadataVersion() {
        $version = [ '2' ]; // core metadata version
        ( new HookRunner( MediaWikiServices::getInstance()->getHookContainer() ) )->onGetMetadataVersion( $version );

        return implode( ';', $version );
    }

    /**
     * Convert metadata version.
     *
     * By default just returns $metadata, but can be used to allow
     * media handlers to convert between metadata versions.
     * @stable to override
     *
     * @param array $metadata Metadata array
     * @param int|string $version Target version
     * @return array Serialized metadata in specified version, or $metadata on fail.
     */
    public function convertMetadataVersion( $metadata, $version = 1 ) {
        return $metadata;
    }

    /**
     * Get a string describing the type of metadata, for display purposes.
     * @stable to override
     *
     * @note This method is currently unused.
     * @param File $image
     * @return string|false
     */
    public function getMetadataType( $image ) {
        return false;
    }

    /**
     * Check if the metadata string is valid for this handler.
     * If it returns MediaHandler::METADATA_BAD (or false), Image
     * will reload the metadata from the file and update the database.
     * MediaHandler::METADATA_GOOD for if the metadata is a-ok,
     * MediaHandler::METADATA_COMPATIBLE if metadata is old but backwards
     * compatible (which may or may not trigger a metadata reload).
     *
     * @note Returning self::METADATA_BAD will trigger a metadata reload from
     *  file on page view. Always returning this from a broken file, or suddenly
     *  triggering as bad metadata for a large number of files can cause
     *  performance problems.
     *
     * @deprecated since 1.37 use isFileMetadataValid
     * @param File $image
     * @param string $metadata The metadata in serialized form
     * @return bool|int
     */
    public function isMetadataValid( $image, $metadata ) {
        return self::METADATA_GOOD;
    }

    /**
     * Check if the metadata is valid for this handler.
     * If it returns MediaHandler::METADATA_BAD (or false), Image
     * will reload the metadata from the file and update the database.
     * MediaHandler::METADATA_GOOD for if the metadata is a-ok,
     * MediaHandler::METADATA_COMPATIBLE if metadata is old but backwards
     * compatible (which may or may not trigger a metadata reload).
     *
     * @note Returning self::METADATA_BAD will trigger a metadata reload from
     *  file on page view. Always returning this from a broken file, or suddenly
     *  triggering as bad metadata for a large number of files can cause
     *  performance problems.
     *
     * This was introduced in 1.37 to replace isMetadataValid(), which took a
     * serialized string as a parameter. Handlers overriding this method are
     * expected to use accessors to get the metadata out of the File. The
     * reasons for the change were to get rid of serialization, and to allow
     * handlers to partially load metadata with getMetadataItem(). For example
     * a handler could just validate a version number.
     *
     * @stable to override
     * @since 1.37
     * @param File $image
     * @return bool|int
     */
    public function isFileMetadataValid( $image ) {
        return self::METADATA_GOOD;
    }

    /**
     * Get an array of standard (FormatMetadata type) metadata values.
     *
     * The returned data is largely the same as that from getMetadata(),
     * but formatted in a standard, stable, handler-independent way.
     * The idea being that some values like ImageDescription or Artist
     * are universal and should be retrievable in a handler generic way.
     *
     * The specific properties are the type of properties that can be
     * handled by the FormatMetadata class. These values are exposed to the
     * user via the filemetadata parser function.
     *
     * Details of the response format of this function can be found at
     * https://www.mediawiki.org/wiki/Manual:File_metadata_handling
     * tl/dr: the response is an associative array of
     * properties keyed by name, but the value can be complex. You probably
     * want to call one of the FormatMetadata::flatten* functions on the
     * property values before using them, or call
     * FormatMetadata::getFormattedData() on the full response array, which
     * transforms all values into prettified, human-readable text.
     *
     * Subclasses overriding this function must return a value which is a
     * valid API response fragment (all associative array keys are valid
     * XML tagnames).
     *
     * Note, if the file simply has no metadata, but the handler supports
     * this interface, it should return an empty array, not false.
     *
     * @stable to override
     *
     * @param File $file
     * @return array|false False if interface not supported
     * @since 1.23
     */
    public function getCommonMetaArray( File $file ) {
        return false;
    }

    /**
     * Get a MediaTransformOutput object representing an alternate of the transformed
     * output which will call an intermediary thumbnail assist script.
     *
     * Used when the repository has a thumbnailScriptUrl option configured.
     *
     * Return false to fall back to the regular getTransform().
     *
     * @stable to override
     *
     * @param File $image
     * @param string $script
     * @param array $params
     * @return ThumbnailImage|false
     */
    public function getScriptedTransform( $image, $script, $params ) {
        return false;
    }

    /**
     * Get a MediaTransformOutput object representing the transformed output. Does not
     * actually do the transform.
     *
     * @stable to override
     *
     * @param File $image
     * @param string $dstPath Filesystem destination path
     * @param string $dstUrl Destination URL to use in output HTML
     * @param array $params Arbitrary set of parameters validated by $this->validateParam()
     * @return MediaTransformOutput
     */
    final public function getTransform( $image, $dstPath, $dstUrl, $params ) {
        return $this->doTransform( $image, $dstPath, $dstUrl, $params, self::TRANSFORM_LATER );
    }

    /**
     * Get a MediaTransformOutput object representing the transformed output. Does the
     * transform unless $flags contains self::TRANSFORM_LATER.
     *
     * @stable to override
     *
     * @param File $image
     * @param string $dstPath Filesystem destination path
     * @param string $dstUrl Destination URL to use in output HTML
     * @param array $params Arbitrary set of parameters validated by $this->validateParam()
     *   Note: These parameters have *not* gone through $this->normaliseParams()
     * @param int $flags A bitfield, may contain self::TRANSFORM_LATER
     * @return MediaTransformOutput
     */
    abstract public function doTransform( $image, $dstPath, $dstUrl, $params, $flags = 0 );

    /**
     * Get the thumbnail extension and MIME type for a given source MIME type
     *
     * @stable to override
     *
     * @param string $ext Extension of original file
     * @param string $mime MIME type of original file
     * @param array|null $params Handler specific rendering parameters
     * @return array Thumbnail extension and MIME type
     */
    public function getThumbType( $ext, $mime, $params = null ) {
        $magic = MediaWikiServices::getInstance()->getMimeAnalyzer();
        if ( !$ext || $magic->isMatchingExtension( $ext, $mime ) === false ) {
            // The extension is not valid for this MIME type and we do
            // recognize the MIME type
            $knownExt = $magic->getExtensionFromMimeTypeOrNull( $mime );
            if ( $knownExt !== null ) {
                return [ $knownExt, $mime ];
            }
        }

        // The extension is correct (true) or the MIME type is unknown to
        // MediaWiki (null)
        return [ $ext, $mime ];
    }

    /**
     * True if the handled types can be transformed
     *
     * @stable to override
     *
     * @param File $file
     * @return bool
     */
    public function canRender( $file ) {
        return true;
    }

    /**
     * True if handled types cannot be displayed directly in a browser
     * but can be rendered
     *
     * @stable to override
     *
     * @param File $file
     * @return bool
     */
    public function mustRender( $file ) {
        return false;
    }

    /**
     * True if the type has multi-page capabilities
     *
     * @stable to override
     *
     * @param File $file
     * @return bool
     */
    public function isMultiPage( $file ) {
        return false;
    }

    /**
     * Page count for a multi-page document, false if unsupported or unknown
     *
     * @stable to override
     *
     * @param File $file
     * @return int|false
     */
    public function pageCount( File $file ) {
        return false;
    }

    /**
     * The material is vectorized and thus scaling is lossless
     *
     * @stable to override
     *
     * @param File $file
     * @return bool
     */
    public function isVectorized( $file ) {
        return false;
    }

    /**
     * The material is an image, and is animated.
     * In particular, video material need not return true.
     * @note Before 1.20, this was a method of ImageHandler only
     *
     * @stable to override
     *
     * @param File $file
     * @return bool
     */
    public function isAnimatedImage( $file ) {
        return false;
    }

    /**
     * If the material is animated, we can animate the thumbnail
     * @since 1.20
     *
     * @stable to override
     *
     * @param File $file
     * @return bool If material is not animated, handler may return any value.
     */
    public function canAnimateThumbnail( $file ) {
        return true;
    }

    /**
     * False if the handler is disabled for all files
     * @stable to override
     *
     * @return bool
     */
    public function isEnabled() {
        return true;
    }

    /**
     * Get an associative array of page dimensions
     * Currently "width" and "height" are understood, but this might be
     * expanded in the future.
     * Returns false if unknown.
     *
     * For a single page document format (!isMultipage()), this should return
     * false.
     *
     * @note For non-paged media, use getImageSize.
     *
     * @stable to override
     *
     * @param File $image
     * @param int $page What page to get dimensions of
     * @return array|false
     */
    public function getPageDimensions( File $image, $page ) {
        return false;
    }

    /**
     * Generic getter for text layer.
     * Currently overloaded by PDF and DjVu handlers
     * @stable to override
     *
     * @param File $image
     * @param int $page Page number to get information for
     * @return string|false Page text or false when no text found or if
     *   unsupported.
     */
    public function getPageText( File $image, $page ) {
        return false;
    }

    /**
     * Get the text of the entire document.
     * @param File $file
     * @return string|false The text of the document or false if unsupported.
     */
    public function getEntireText( File $file ) {
        $numPages = $file->pageCount();
        if ( !$numPages ) {
            // Not a multipage document
            return $this->getPageText( $file, 1 );
        }
        $document = '';
        for ( $i = 1; $i <= $numPages; $i++ ) {
            $curPage = $this->getPageText( $file, $i );
            if ( is_string( $curPage ) ) {
                $document .= $curPage . "\n";
            }
        }
        if ( $document !== '' ) {
            return $document;
        }
        return false;
    }

    /**
     * Get an array structure that looks like this:
     *
     * [
     *    'visible' => [
     *       'Human-readable name' => 'Human readable value',
     *       ...
     *    ],
     *    'collapsed' => [
     *       'Human-readable name' => 'Human readable value',
     *       ...
     *    ]
     * ]
     * The UI will format this into a table where the visible fields are always
     * visible, and the collapsed fields are optionally visible.
     *
     * The function should return false if there is no metadata to display.
     */

    /**
     * @todo FIXME: This interface is not very flexible. The media handler
     * should generate HTML instead. It can do all the formatting according
     * to some standard. That makes it possible to do things like visual
     * indication of grouped and chained streams in ogg container files.
     * @stable to override
     *
     * @param File $image
     * @param IContextSource|false $context
     * @return array|false
     */
    public function formatMetadata( $image, $context = false ) {
        return false;
    }

    /** sorts the visible/invisible field.
     * Split off from ImageHandler::formatMetadata, as used by more than
     * one type of handler.
     *
     * This is used by the media handlers that use the FormatMetadata class
     *
     * @stable to override
     *
     * @param array $metadataArray
     * @param IContextSource|false $context
     * @return array[] Array for use displaying metadata.
     */
    protected function formatMetadataHelper( $metadataArray, $context = false ) {
        $result = [
            'visible' => [],
            'collapsed' => []
        ];

        // Allow this MediaHandler to override formatting on certain values
        foreach ( $metadataArray as $tag => $vals ) {
            $v = $this->formatTag( $tag, $vals, $context );
            if ( $v === false ) {
                // Use default formatting
                continue;
            }
            if ( $v === null ) {
                // Remove this tag, don't format it for display
                unset( $metadataArray[$tag] );
            } else {
                // Allow subclass to override default formatting.
                $metadataArray[$tag] = [ '_formatted' => $v ];
                if ( isset( $v['_type'] ) ) {
                    $metadataArray[$tag]['_type'] = $v['_type'];
                    unset( $metadataArray[$tag]['_formatted']['_type'] );
                }
            }
        }

        $formatted = FormatMetadata::getFormattedData( $metadataArray, $context );
        // Sort fields into visible and collapsed
        $visibleFields = $this->visibleMetadataFields();
        foreach ( $formatted as $name => $value ) {
            $tag = strtolower( $name );
            self::addMeta( $result,
                in_array( $tag, $visibleFields ) ? 'visible' : 'collapsed',
                'exif',
                $tag,
                $value
            );
        }

        return $result;
    }

    /**
     * Override default formatting for the given metadata field.
     *
     * @stable to override
     *
     * @param string $key The metadata field key
     * @param string|array $vals The unformatted value of this metadata field
     * @param IContextSource|false $context Context to use (optional)
     * @return false|null|string|array False to use default formatting, null
     *   to remove this tag from the formatted list; otherwise return
     *   a formatted HTML string (or array of them).
     */
    protected function formatTag( string $key, $vals, $context = false ) {
        return false; // Use default formatting
    }

    /**
     * Get a list of metadata items which should be displayed when
     * the metadata table is collapsed.
     *
     * @stable to override
     *
     * @return string[]
     */
    protected function visibleMetadataFields() {
        return FormatMetadata::getVisibleFields();
    }

    /**
     * This is used to generate an array element for each metadata value
     * That array is then used to generate the table of metadata values
     * on the image page
     *
     * @param array &$array An array containing elements for each type of visibility
     *   and each of those elements being an array of metadata items. This function adds
     *   a value to that array.
     * @param string $visibility ('visible' or 'collapsed') if this value is hidden
     *   by default.
     * @param string $type Type of metadata tag (currently always 'exif')
     * @param string $id The name of the metadata tag (like 'artist' for example).
     *   its name in the table displayed is the message "$type-$id" (Ex exif-artist ).
     * @param string $value Thingy goes into a wikitext table; it used to be escaped but
     *   that was incompatible with previous practise of customized display
     *   with wikitext formatting via messages such as 'exif-model-value'.
     *   So the escaping is taken back out, but generally this seems a confusing
     *   interface.
     * @param bool|string $param Value to pass to the message for the name of the field
     *   as $1. Currently this parameter doesn't seem to ever be used.
     *
     * Note, everything here is passed through the parser later on (!)
     */
    protected static function addMeta( &$array, $visibility, $type, $id, $value, $param = false ) {
        $msg = wfMessage( "$type-$id", $param );
        if ( $msg->exists() ) {
            $name = $msg->text();
        } else {
            // This is for future compatibility when using instant commons.
            // So as to not display as ugly a name if a new metadata
            // property is defined that we don't know about
            // (not a major issue since such a property would be collapsed
            // by default).
            wfDebug( __METHOD__ . ' Unknown metadata name: ' . $id );
            $name = wfEscapeWikiText( $id );
        }
        $array[$visibility][] = [
            'id' => "$type-$id",
            'name' => $name,
            'value' => $value
        ];
    }

    /**
     * Short description. Shown on Special:Search results.
     *
     * @stable to override
     *
     * @param File $file
     * @return string
     */
    public function getShortDesc( $file ) {
        return self::getGeneralShortDesc( $file );
    }

    /**
     * Long description. Shown under image on image description page surrounded by ().
     *
     * @stable to override
     *
     * @param File $file
     * @return string
     */
    public function getLongDesc( $file ) {
        return self::getGeneralLongDesc( $file );
    }

    /**
     * Used instead of getShortDesc if there is no handler registered for file.
     *
     * @param File $file
     * @return string
     */
    public static function getGeneralShortDesc( $file ) {
        global $wgLang;

        return htmlspecialchars( $wgLang->formatSize( $file->getSize() ) );
    }

    /**
     * Used instead of getLongDesc if there is no handler registered for file.
     *
     * @param File $file
     * @return string
     */
    public static function getGeneralLongDesc( $file ) {
        return wfMessage( 'file-info' )->sizeParams( $file->getSize() )
            ->params( '<span class="mime-type">' . $file->getMimeType() . '</span>' )->parse();
    }

    /**
     * Calculate the largest thumbnail width for a given original file size
     * such that the thumbnail's height is at most $maxHeight.
     * @param int $boxWidth Width of the thumbnail box.
     * @param int $boxHeight Height of the thumbnail box.
     * @param int $maxHeight Maximum height expected for the thumbnail.
     * @return int
     */
    public static function fitBoxWidth( $boxWidth, $boxHeight, $maxHeight ) {
        $idealWidth = $boxWidth * $maxHeight / $boxHeight;
        $roundedUp = ceil( $idealWidth );
        if ( round( $roundedUp * $boxHeight / $boxWidth ) > $maxHeight ) {
            return (int)floor( $idealWidth );
        }
        return $roundedUp;
    }

    /**
     * Shown in file history box on image description page.
     *
     * @stable to override
     *
     * @param File $file
     * @return string Dimensions
     */
    public function getDimensionsString( $file ) {
        return '';
    }

    /**
     * Modify the parser object post-transform.
     *
     * This is often used to do $parser->addOutputHook(),
     * in order to add some javascript to render a viewer.
     * See TimedMediaHandler or OggHandler for an example.
     *
     * @stable to override
     *
     * @param Parser $parser
     * @param File $file
     */
    public function parserTransformHook( $parser, $file ) {
    }

    /**
     * File validation hook called on upload.
     *
     * If the file at the given local path is not valid, or its MIME type does not
     * match the handler class, a Status object should be returned containing
     * relevant errors.
     *
     * @stable to override
     *
     * @param string $fileName The local path to the file.
     * @return Status
     */
    public function verifyUpload( $fileName ) {
        return Status::newGood();
    }

    /**
     * Check for zero-sized thumbnails. These can be generated when
     * no disk space is available or some other error occurs
     *
     * @stable to override
     *
     * @param string $dstPath The location of the suspect file
     * @param int $retval Return value of some shell process, file will be deleted if this is non-zero
     * @return bool True if removed, false otherwise
     */
    public function removeBadFile( $dstPath, $retval = 0 ) {
        if ( file_exists( $dstPath ) ) {
            $thumbstat = stat( $dstPath );
            if ( $thumbstat['size'] == 0 || $retval != 0 ) {
                $result = unlink( $dstPath );

                if ( $result ) {
                    wfDebugLog( 'thumbnail',
                        sprintf( 'Removing bad %d-byte thumbnail "%s". unlink() succeeded',
                            $thumbstat['size'], $dstPath ) );
                } else {
                    wfDebugLog( 'thumbnail',
                        sprintf( 'Removing bad %d-byte thumbnail "%s". unlink() failed',
                            $thumbstat['size'], $dstPath ) );
                }

                return true;
            }
        }

        return false;
    }

    /**
     * Remove files from the purge list.
     *
     * This is used by some video handlers to prevent ?action=purge
     * from removing a transcoded video, which is expensive to
     * regenerate.
     *
     * @see LocalFile::purgeThumbnails
     * @stable to override
     *
     * @param array &$files
     * @param array $options Purge options. Currently will always be
     *  an array with a single key 'forThumbRefresh' set to true.
     */
    public function filterThumbnailPurgeList( &$files, $options ) {
        // Do nothing
    }

    /**
     * True if the handler can rotate the media
     * @since 1.24 non-static. From 1.21-1.23 was static
     * @stable to override
     *
     * @return bool
     */
    public function canRotate() {
        return false;
    }

    /**
     * On supporting image formats, try to read out the low-level orientation
     * of the file and return the angle that the file needs to be rotated to
     * be viewed.
     *
     * This information is only useful when manipulating the original file;
     * the width and height we normally work with is logical, and will match
     * any produced output views.
     *
     * For files we don't know, we return 0.
     *
     * @stable to override
     *
     * @param File $file
     * @return int 0, 90, 180 or 270
     */
    public function getRotation( $file ) {
        return 0;
    }

    /**
     * Log an error that occurred in an external process
     *
     * Moved from BitmapHandler to MediaHandler with MediaWiki 1.23
     *
     * @since 1.23
     * @param int $retval
     * @param string $err Error reported by command. Anything longer than
     * MediaHandler::MAX_ERR_LOG_SIZE is stripped off.
     * @param string $cmd
     */
    protected function logErrorForExternalProcess( $retval, $err, $cmd ) {
        # Keep error output limited (T59985)
        $errMessage = trim( substr( $err, 0, self::MAX_ERR_LOG_SIZE ) );

        wfDebugLog( 'thumbnail',
            sprintf( 'thumbnail failed on %s: error %d "%s" from "%s"',
                    wfHostname(), $retval, $errMessage, $cmd ) );
    }

    /**
     * Get list of languages file can be viewed in.
     *
     * @stable to override
     *
     * @param File $file
     * @return string[] Array of IETF language codes, or empty array if unsupported.
     * @since 1.23
     */
    public function getAvailableLanguages( File $file ) {
        return [];
    }

    /**
     * When overridden in a descendant class, returns a language code most suiting
     *
     * @stable to override
     *
     * @since 1.32
     *
     * @param string $userPreferredLanguage IETF Language code requested
     * @param string[] $availableLanguages IETF Languages present in the file
     * @return string|null IETF Language code picked or null if not supported/available
     */
    public function getMatchedLanguage( $userPreferredLanguage, array $availableLanguages ) {
        return null;
    }

    /**
     * On file types that support renderings in multiple languages,
     * which language is used by default if unspecified.
     *
     * If getAvailableLanguages returns a non-empty array, this must return
     * a valid language code. Otherwise can return null if files of this
     * type do not support alternative language renderings.
     * It can also return 'und' for explicitly requesting an undetermined language
     *
     * @stable to override
     *
     * @param File $file
     * @return string|null IETF Language code or null if multi-language not supported for filetype.
     * @since 1.23
     */
    public function getDefaultRenderLanguage( File $file ) {
        return null;
    }

    /**
     * If it's an audio file, return the length of the file. Otherwise 0.
     *
     * File::getLength() existed for a long time, but was calling a method
     * that only existed in some subclasses of this class (The TMH ones).
     *
     * @stable to override
     *
     * @param File $file
     * @return float Length in seconds
     * @since 1.23
     */
    public function getLength( $file ) {
        return 0.0;
    }

    /**
     * True if creating thumbnails from the file is large or otherwise resource-intensive.
     * @stable to override
     *
     * @param File $file
     * @return bool
     */
    public function isExpensiveToThumbnail( $file ) {
        return false;
    }

    /**
     * Returns whether or not this handler supports the chained generation of thumbnails according
     * to buckets
     * @stable to override
     *
     * @return bool
     * @since 1.24
     */
    public function supportsBucketing() {
        return false;
    }

    /**
     * Returns a normalised params array for which parameters have been cleaned up for bucketing
     * purposes
     * @stable to override
     *
     * @param array $params
     * @return array
     */
    public function sanitizeParamsForBucketing( $params ) {
        return $params;
    }

    /**
     * Gets configuration for the file warning message. Return value of
     * the following structure:
     *   [
     *     // Required, module with messages loaded for the client
     *     'module' => 'example.filewarning.messages',
     *     // Required, array of names of messages
     *     'messages' => [
     *       // Required, main warning message
     *       'main' => 'example-filewarning-main',
     *       // Optional, header for warning dialog
     *       'header' => 'example-filewarning-header',
     *       // Optional, footer for warning dialog
     *       'footer' => 'example-filewarning-footer',
     *       // Optional, text for more-information link (see below)
     *       'info' => 'example-filewarning-info',
     *     ],
     *     // Optional, link for more information
     *     'link' => 'http://example.com',
     *   ]
     *
     * Returns null if no warning is necessary.
     * @stable to override
     * @param File $file
     * @return array|null
     */
    public function getWarningConfig( $file ) {
        return null;
    }

    /**
     * Converts a dimensions array about a potentially multipage document from an
     * exhaustive list of ordered page numbers to a list of page ranges
     * @param array[] $pagesByDimensions
     * @return string
     * @since 1.30
     */
    public static function getPageRangesByDimensions( $pagesByDimensions ) {
        $pageRangesByDimensions = [];

        foreach ( $pagesByDimensions as $dimensions => $pageList ) {
            $ranges = [];
            $firstPage = $pageList[0];
            $lastPage = $firstPage - 1;

            foreach ( $pageList as $page ) {
                if ( $page > $lastPage + 1 ) {
                    if ( $firstPage !== $lastPage ) {
                        $ranges[] = "$firstPage-$lastPage";
                    } else {
                        $ranges[] = "$firstPage";
                    }

                    $firstPage = $page;
                }

                $lastPage = $page;
            }

            if ( $firstPage != $lastPage ) {
                $ranges[] = "$firstPage-$lastPage";
            } else {
                $ranges[] = "$firstPage";
            }

            $pageRangesByDimensions[ $dimensions ] = $ranges;
        }

        $dimensionsString = [];
        foreach ( $pageRangesByDimensions as $dimensions => $pageRanges ) {
            $dimensionsString[] = "$dimensions:" . implode( ',', $pageRanges );
        }

        return implode( '/', $dimensionsString );
    }

    /**
     * Get useful response headers for GET/HEAD requests for a file with the given metadata
     * @stable to override
     *
     * @param array $metadata Contains this handler's unserialized getMetadata() for a file
     * @return array
     * @since 1.30
     */
    public function getContentHeaders( $metadata ) {
        return [ 'X-Content-Dimensions' => '' ]; // T175689
    }

    /**
     * If this returns true, LocalFile may split metadata up and store its
     * constituent items separately. This only makes sense if the handler calls
     * File::getMetadataItem() or File::getMetadataItems() instead of
     * requesting the whole array at once.
     *
     * @return bool
     */
    public function useSplitMetadata() {
        return false;
    }
}