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diff --git a/www/wiki/includes/media/BitmapMetadataHandler.php b/www/wiki/includes/media/BitmapMetadataHandler.php
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+++ b/www/wiki/includes/media/BitmapMetadataHandler.php
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+<?php
+/**
+ * Extraction of metadata from different bitmap image types.
+ *
+ * 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
+ * @ingroup Media
+ */
+
+use MediaWiki\Logger\LoggerFactory;
+
+/**
+ * Class to deal with reconciling and extracting metadata from bitmap images.
+ * This is meant to comply with http://www.metadataworkinggroup.org/pdf/mwg_guidance.pdf
+ *
+ * This sort of acts as an intermediary between MediaHandler::getMetadata
+ * and the various metadata extractors.
+ *
+ * @todo Other image formats.
+ * @ingroup Media
+ */
+class BitmapMetadataHandler {
+	/** @var array */
+	private $metadata = [];
+
+	/** @var array Metadata priority */
+	private $metaPriority = [
+		20 => [ 'other' ],
+		40 => [ 'native' ],
+		60 => [ 'iptc-good-hash', 'iptc-no-hash' ],
+		70 => [ 'xmp-deprecated' ],
+		80 => [ 'xmp-general' ],
+		90 => [ 'xmp-exif' ],
+		100 => [ 'iptc-bad-hash' ],
+		120 => [ 'exif' ],
+	];
+
+	/** @var string */
+	private $iptcType = 'iptc-no-hash';
+
+	/**
+	 * This does the photoshop image resource app13 block
+	 * of interest, IPTC-IIM metadata is stored here.
+	 *
+	 * Mostly just calls doPSIR and doIPTC
+	 *
+	 * @param string $app13 String containing app13 block from jpeg file
+	 */
+	private function doApp13( $app13 ) {
+		try {
+			$this->iptcType = JpegMetadataExtractor::doPSIR( $app13 );
+		} catch ( Exception $e ) {
+			// Error reading the iptc hash information.
+			// This probably means the App13 segment is something other than what we expect.
+			// However, still try to read it, and treat it as if the hash didn't exist.
+			wfDebug( "Error parsing iptc data of file: " . $e->getMessage() . "\n" );
+			$this->iptcType = 'iptc-no-hash';
+		}
+
+		$iptc = IPTC::parse( $app13 );
+		$this->addMetadata( $iptc, $this->iptcType );
+	}
+
+	/**
+	 * Get exif info using exif class.
+	 * Basically what used to be in BitmapHandler::getMetadata().
+	 * Just calls stuff in the Exif class.
+	 *
+	 * Parameters are passed to the Exif class.
+	 *
+	 * @param string $filename
+	 * @param string $byteOrder
+	 */
+	function getExif( $filename, $byteOrder ) {
+		global $wgShowEXIF;
+		if ( file_exists( $filename ) && $wgShowEXIF ) {
+			$exif = new Exif( $filename, $byteOrder );
+			$data = $exif->getFilteredData();
+			if ( $data ) {
+				$this->addMetadata( $data, 'exif' );
+			}
+		}
+	}
+
+	/** Add misc metadata. Warning: atm if the metadata category
+	 * doesn't have a priority, it will be silently discarded.
+	 *
+	 * @param array $metaArray Array of metadata values
+	 * @param string $type Type. defaults to other. if two things have the same type they're merged
+	 */
+	function addMetadata( $metaArray, $type = 'other' ) {
+		if ( isset( $this->metadata[$type] ) ) {
+			/* merge with old data */
+			$metaArray = $metaArray + $this->metadata[$type];
+		}
+
+		$this->metadata[$type] = $metaArray;
+	}
+
+	/**
+	 * Merge together the various types of metadata
+	 * the different types have different priorites,
+	 * and are merged in order.
+	 *
+	 * This function is generally called by the media handlers' getMetadata()
+	 *
+	 * @return array Metadata array
+	 */
+	function getMetadataArray() {
+		// this seems a bit ugly... This is all so its merged in right order
+		// based on the MWG recomendation.
+		$temp = [];
+		krsort( $this->metaPriority );
+		foreach ( $this->metaPriority as $pri ) {
+			foreach ( $pri as $type ) {
+				if ( isset( $this->metadata[$type] ) ) {
+					// Do some special casing for multilingual values.
+					// Don't discard translations if also as a simple value.
+					foreach ( $this->metadata[$type] as $itemName => $item ) {
+						if ( is_array( $item ) && isset( $item['_type'] ) && $item['_type'] === 'lang' ) {
+							if ( isset( $temp[$itemName] ) && !is_array( $temp[$itemName] ) ) {
+								$default = $temp[$itemName];
+								$temp[$itemName] = $item;
+								$temp[$itemName]['x-default'] = $default;
+								unset( $this->metadata[$type][$itemName] );
+							}
+						}
+					}
+
+					$temp = $temp + $this->metadata[$type];
+				}
+			}
+		}
+
+		return $temp;
+	}
+
+	/** Main entry point for jpeg's.
+	 *
+	 * @param string $filename Filename (with full path)
+	 * @return array Metadata result array.
+	 * @throws MWException On invalid file.
+	 */
+	static function Jpeg( $filename ) {
+		$showXMP = XMPReader::isSupported();
+		$meta = new self();
+
+		$seg = JpegMetadataExtractor::segmentSplitter( $filename );
+
+		if ( isset( $seg['COM'] ) && isset( $seg['COM'][0] ) ) {
+			$meta->addMetadata( [ 'JPEGFileComment' => $seg['COM'] ], 'native' );
+		}
+		if ( isset( $seg['PSIR'] ) && count( $seg['PSIR'] ) > 0 ) {
+			foreach ( $seg['PSIR'] as $curPSIRValue ) {
+				$meta->doApp13( $curPSIRValue );
+			}
+		}
+		if ( isset( $seg['XMP'] ) && $showXMP ) {
+			$xmp = new XMPReader( LoggerFactory::getInstance( 'XMP' ), $filename );
+			$xmp->parse( $seg['XMP'] );
+			foreach ( $seg['XMP_ext'] as $xmpExt ) {
+				/* Support for extended xmp in jpeg files
+				 * is not well tested and a bit fragile.
+				 */
+				$xmp->parseExtended( $xmpExt );
+			}
+			$res = $xmp->getResults();
+			foreach ( $res as $type => $array ) {
+				$meta->addMetadata( $array, $type );
+			}
+		}
+
+		$meta->getExif( $filename, isset( $seg['byteOrder'] ) ? $seg['byteOrder'] : 'BE' );
+
+		return $meta->getMetadataArray();
+	}
+
+	/** Entry point for png
+	 * At some point in the future this might
+	 * merge the png various tEXt chunks to that
+	 * are interesting, but for now it only does XMP
+	 *
+	 * @param string $filename Full path to file
+	 * @return array Array for storage in img_metadata.
+	 */
+	public static function PNG( $filename ) {
+		$showXMP = XMPReader::isSupported();
+
+		$meta = new self();
+		$array = PNGMetadataExtractor::getMetadata( $filename );
+		if ( isset( $array['text']['xmp']['x-default'] )
+			&& $array['text']['xmp']['x-default'] !== '' && $showXMP
+		) {
+			$xmp = new XMPReader( LoggerFactory::getInstance( 'XMP' ), $filename );
+			$xmp->parse( $array['text']['xmp']['x-default'] );
+			$xmpRes = $xmp->getResults();
+			foreach ( $xmpRes as $type => $xmpSection ) {
+				$meta->addMetadata( $xmpSection, $type );
+			}
+		}
+		unset( $array['text']['xmp'] );
+		$meta->addMetadata( $array['text'], 'native' );
+		unset( $array['text'] );
+		$array['metadata'] = $meta->getMetadataArray();
+		$array['metadata']['_MW_PNG_VERSION'] = PNGMetadataExtractor::VERSION;
+
+		return $array;
+	}
+
+	/** function for gif images.
+	 *
+	 * They don't really have native metadata, so just merges together
+	 * XMP and image comment.
+	 *
+	 * @param string $filename Full path to file
+	 * @return array Metadata array
+	 */
+	public static function GIF( $filename ) {
+		$meta = new self();
+		$baseArray = GIFMetadataExtractor::getMetadata( $filename );
+
+		if ( count( $baseArray['comment'] ) > 0 ) {
+			$meta->addMetadata( [ 'GIFFileComment' => $baseArray['comment'] ], 'native' );
+		}
+
+		if ( $baseArray['xmp'] !== '' && XMPReader::isSupported() ) {
+			$xmp = new XMPReader( LoggerFactory::getInstance( 'XMP' ), $filename );
+			$xmp->parse( $baseArray['xmp'] );
+			$xmpRes = $xmp->getResults();
+			foreach ( $xmpRes as $type => $xmpSection ) {
+				$meta->addMetadata( $xmpSection, $type );
+			}
+		}
+
+		unset( $baseArray['comment'] );
+		unset( $baseArray['xmp'] );
+
+		$baseArray['metadata'] = $meta->getMetadataArray();
+		$baseArray['metadata']['_MW_GIF_VERSION'] = GIFMetadataExtractor::VERSION;
+
+		return $baseArray;
+	}
+
+	/**
+	 * This doesn't do much yet, but eventually I plan to add
+	 * XMP support for Tiff. (PHP's exif support already extracts
+	 * but needs some further processing because PHP's exif support
+	 * is stupid...)
+	 *
+	 * @todo Add XMP support, so this function actually makes sense to put here.
+	 *
+	 * The various exceptions this throws are caught later.
+	 * @param string $filename
+	 * @throws MWException
+	 * @return array The metadata.
+	 */
+	public static function Tiff( $filename ) {
+		if ( file_exists( $filename ) ) {
+			$byteOrder = self::getTiffByteOrder( $filename );
+			if ( !$byteOrder ) {
+				throw new MWException( "Error determining byte order of $filename" );
+			}
+			$exif = new Exif( $filename, $byteOrder );
+			$data = $exif->getFilteredData();
+			if ( $data ) {
+				$data['MEDIAWIKI_EXIF_VERSION'] = Exif::version();
+
+				return $data;
+			} else {
+				throw new MWException( "Could not extract data from tiff file $filename" );
+			}
+		} else {
+			throw new MWException( "File doesn't exist - $filename" );
+		}
+	}
+
+	/**
+	 * Read the first 2 bytes of a tiff file to figure out
+	 * Little Endian or Big Endian. Needed for exif stuff.
+	 *
+	 * @param string $filename
+	 * @return string 'BE' or 'LE' or false
+	 */
+	static function getTiffByteOrder( $filename ) {
+		$fh = fopen( $filename, 'rb' );
+		if ( !$fh ) {
+			return false;
+		}
+		$head = fread( $fh, 2 );
+		fclose( $fh );
+
+		switch ( $head ) {
+			case 'II':
+				return 'LE'; // II for intel.
+			case 'MM':
+				return 'BE'; // MM for motorla.
+			default:
+				return false; // Something went wrong.
+
+		}
+	}
+}