MediaHandler.php

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<?php
abstract class MediaHandler {
        const TRANSFORM_LATER = 1;
        const METADATA_GOOD = true;
        const METADATA_BAD = false;
        const METADATA_COMPATIBLE = 2; // for old but backwards compatible.
        static $handlers = array();

        static function getHandler( $type ) {
                global $wgMediaHandlers;
                if ( !isset( $wgMediaHandlers[$type] ) ) {
                        wfDebug( __METHOD__ . ": no handler found for $type.\n" );
                        return false;
                }
                $class = $wgMediaHandlers[$type];
                if ( !isset( self::$handlers[$class] ) ) {
                        self::$handlers[$class] = new $class;
                        if ( !self::$handlers[$class]->isEnabled() ) {
                                self::$handlers[$class] = false;
                        }
                }
                return self::$handlers[$class];
        }

        abstract function getParamMap();

        abstract function validateParam( $name, $value );

        abstract function makeParamString( $params );

        abstract function parseParamString( $str );

        abstract function normaliseParams( $image, &$params );

        abstract function getImageSize( $image, $path );

        function getMetadata( $image, $path ) { return ''; }

        static function getMetadataVersion () {
                $version = Array( '2' ); // core metadata version
                wfRunHooks( 'GetMetadataVersion', Array( &$version ) );
                return implode( ';', $version);
        }

        function convertMetadataVersion( $metadata, $version = 1 ) {
                if ( !is_array( $metadata ) ) {

                        //unserialize to keep return parameter consistent.
                        wfSuppressWarnings();
                        $ret = unserialize( $metadata );
                        wfRestoreWarnings();
                        return $ret;
                }
                return $metadata;
        }

        function getMetadataType( $image ) { return false; }

        function isMetadataValid( $image, $metadata ) {
                return self::METADATA_GOOD;
        }

        function getScriptedTransform( $image, $script, $params ) {
                return false;
        }

        final function getTransform( $image, $dstPath, $dstUrl, $params ) {
                return $this->doTransform( $image, $dstPath, $dstUrl, $params, self::TRANSFORM_LATER );
        }

        abstract function doTransform( $image, $dstPath, $dstUrl, $params, $flags = 0 );

        function getThumbType( $ext, $mime, $params = null ) {
                $magic = MimeMagic::singleton();
                if ( !$ext || $magic->isMatchingExtension( $ext, $mime ) === false ) {
                        // The extension is not valid for this mime type and we do
                        // recognize the mime type
                        $extensions = $magic->getExtensionsForType( $mime );
                        if ( $extensions ) {
                                return array( strtok( $extensions, ' ' ), $mime );
                        }
                }

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

        public function getStreamHeaders( $metadata ) {
                return array();
        }

        function canRender( $file ) { return true; }
        function mustRender( $file ) { return false; }
        function isMultiPage( $file ) { return false; }
        function pageCount( $file ) { return false; }
        function isVectorized( $file ) { return false; }
        function isAnimatedImage( $file ) { return false; }
        function canAnimateThumbnail( $file ) { return true; }
        function isEnabled() { return true; }

        function getPageDimensions( $image, $page ) {
                $gis = $this->getImageSize( $image, $image->getLocalRefPath() );
                return array(
                        'width' => $gis[0],
                        'height' => $gis[1]
                );
        }

        function getPageText( $image, $page ) {
                return false;
        }

        function formatMetadata( $image ) {
                return false;
        }

        function formatMetadataHelper( $metadataArray ) {
                $result = array(
                        'visible' => array(),
                        'collapsed' => array()
                );

                $formatted = FormatMetadata::getFormattedData( $metadataArray );
                // 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;
        }

        function visibleMetadataFields() {
                $fields = array();
                $lines = explode( "\n", wfMessage( 'metadata-fields' )->inContentLanguage()->text() );
                foreach( $lines as $line ) {
                        $matches = array();
                        if( preg_match( '/^\\*\s*(.*?)\s*$/', $line, $matches ) ) {
                                $fields[] = $matches[1];
                        }
                }
                $fields = array_map( 'strtolower', $fields );
                return $fields;
        }

        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 . "\n" );
                        $name = wfEscapeWikiText( $id );
                }
                $array[$visibility][] = array(
                        'id' => "$type-$id",
                        'name' => $name,
                        'value' => $value
                );
        }

        function getShortDesc( $file ) {
                global $wgLang;
                return htmlspecialchars( $wgLang->formatSize( $file->getSize() ) );
        }

        function getLongDesc( $file ) {
                global $wgLang;
                return wfMessage( 'file-info', htmlspecialchars( $wgLang->formatSize( $file->getSize() ) ),
                        $file->getMimeType() )->parse();
        }

        static function getGeneralShortDesc( $file ) {
                global $wgLang;
                return $wgLang->formatSize( $file->getSize() );
        }

        static function getGeneralLongDesc( $file ) {
                global $wgLang;
                return wfMessage( 'file-info', $wgLang->formatSize( $file->getSize() ),
                        $file->getMimeType() )->parse();
        }

        public static function fitBoxWidth( $boxWidth, $boxHeight, $maxHeight ) {
                $idealWidth = $boxWidth * $maxHeight / $boxHeight;
                $roundedUp = ceil( $idealWidth );
                if( round( $roundedUp * $boxHeight / $boxWidth ) > $maxHeight ) {
                        return floor( $idealWidth );
                } else {
                        return $roundedUp;
                }
        }

        function getDimensionsString( $file ) {
                return '';
        }

        function parserTransformHook( $parser, $file ) {}

        function verifyUpload( $fileName ) {
                return Status::newGood();
        }

        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;
        }

        public function filterThumbnailPurgeList( &$files, $options ) {
                // Do nothing
        }

        /*
         * True if the handler can rotate the media
         * @since 1.21
         * @return bool
         */
        public static function canRotate() {
                return false;
        }
}