Add "extended" file metadata to API
[lhc/web/wiklou.git] / includes / media / FormatMetadata.php
old mode 100644 (file)
new mode 100755 (executable)
index 1c5136f..17de74a
@@ -43,8 +43,9 @@
  * is already a large number of messages using the 'exif' prefix.
  *
  * @ingroup Media
+ * @since 1.23 the class extends ContextSource and various formerly-public internal methods are private
  */
-class FormatMetadata {
+class FormatMetadata extends ContextSource {
 
        /**
         * Numbers given by Exif user agents are often magical, that is they
@@ -52,13 +53,33 @@ class FormatMetadata {
         * value which most of the time are plain integers. This function
         * formats Exif (and other metadata) values into human readable form.
         *
+        * This is the usual entry point for this class.
+        *
         * @param array $tags the Exif data to format ( as returned by
         *                    Exif::getFilteredData() or BitmapMetadataHandler )
+        * @param IContextSource $context Context to use (optional)
         * @return array
         */
-       public static function getFormattedData( $tags ) {
-               global $wgLang;
+       public static function getFormattedData( $tags, $context = false ) {
+               $obj = new FormatMetadata;
+               if ( $context ) {
+                       $obj->setContext( $context );
+               }
+               return $obj->makeFormattedData( $tags );
+       }
 
+       /**
+        * Numbers given by Exif user agents are often magical, that is they
+        * should be replaced by a detailed explanation depending on their
+        * value which most of the time are plain integers. This function
+        * formats Exif (and other metadata) values into human readable form.
+        *
+        * @param array $tags the Exif data to format ( as returned by
+        *                    Exif::getFilteredData() or BitmapMetadataHandler )
+        * @return array
+        * @since 1.23
+        */
+       public function makeFormattedData( $tags ) {
                $resolutionunit = !isset( $tags['ResolutionUnit'] ) || $tags['ResolutionUnit'] == 2 ? 2 : 3;
                unset( $tags['ResolutionUnit'] );
 
@@ -107,7 +128,7 @@ class FormatMetadata {
                                        $time = wfTimestamp( TS_MW, '1971:01:01 ' . $tags[$tag] );
                                        // the 1971:01:01 is just a placeholder, and not shown to user.
                                        if ( $time && intval( $time ) > 0 ) {
-                                               $tags[$tag] = $wgLang->time( $time );
+                                               $tags[$tag] = $this->getLanguage()->time( $time );
                                        }
                                } catch ( TimestampException $e ) {
                                        // This shouldn't happen, but we've seen bad formats
@@ -121,7 +142,7 @@ class FormatMetadata {
                        // instead of the other props which are single
                        // valued (mostly) so handle as a special case.
                        if ( $tag === 'Contact' ) {
-                               $vals = self::collapseContactInfo( $vals );
+                               $vals = $this->collapseContactInfo( $vals );
                                continue;
                        }
 
@@ -133,7 +154,7 @@ class FormatMetadata {
                                        case 1: case 2: case 3: case 4:
                                        case 5: case 6: case 7: case 8:
                                        case 32773: case 32946: case 34712:
-                                               $val = self::msg( $tag, $val );
+                                               $val = $this->exifMsg( $tag, $val );
                                                break;
                                        default:
                                                /* If not recognized, display as is. */
@@ -144,7 +165,7 @@ class FormatMetadata {
                                case 'PhotometricInterpretation':
                                        switch ( $val ) {
                                        case 2: case 6:
-                                               $val = self::msg( $tag, $val );
+                                               $val = $this->exifMsg( $tag, $val );
                                                break;
                                        default:
                                                /* If not recognized, display as is. */
@@ -155,7 +176,7 @@ class FormatMetadata {
                                case 'Orientation':
                                        switch ( $val ) {
                                        case 1: case 2: case 3: case 4: case 5: case 6: case 7: case 8:
-                                               $val = self::msg( $tag, $val );
+                                               $val = $this->exifMsg( $tag, $val );
                                                break;
                                        default:
                                                /* If not recognized, display as is. */
@@ -166,7 +187,7 @@ class FormatMetadata {
                                case 'PlanarConfiguration':
                                        switch ( $val ) {
                                        case 1: case 2:
-                                               $val = self::msg( $tag, $val );
+                                               $val = $this->exifMsg( $tag, $val );
                                                break;
                                        default:
                                                /* If not recognized, display as is. */
@@ -179,7 +200,7 @@ class FormatMetadata {
                                        switch ( $val ) {
                                        case 1:
                                        case 2:
-                                               $val = self::msg( $tag, $val );
+                                               $val = $this->exifMsg( $tag, $val );
                                                break;
                                        default:
                                                /* If not recognized, display as is. */
@@ -191,10 +212,10 @@ class FormatMetadata {
                                case 'YResolution':
                                        switch ( $resolutionunit ) {
                                                case 2:
-                                                       $val = self::msg( 'XYResolution', 'i', self::formatNum( $val ) );
+                                                       $val = $this->exifMsg( 'XYResolution', 'i', $this->formatNum( $val ) );
                                                        break;
                                                case 3:
-                                                       $val = self::msg( 'XYResolution', 'c', self::formatNum( $val ) );
+                                                       $val = $this->exifMsg( 'XYResolution', 'c', $this->formatNum( $val ) );
                                                        break;
                                                default:
                                                        /* If not recognized, display as is. */
@@ -210,7 +231,7 @@ class FormatMetadata {
                                case 'ColorSpace':
                                        switch ( $val ) {
                                        case 1: case 65535:
-                                               $val = self::msg( $tag, $val );
+                                               $val = $this->exifMsg( $tag, $val );
                                                break;
                                        default:
                                                /* If not recognized, display as is. */
@@ -221,7 +242,7 @@ class FormatMetadata {
                                case 'ComponentsConfiguration':
                                        switch ( $val ) {
                                        case 0: case 1: case 2: case 3: case 4: case 5: case 6:
-                                               $val = self::msg( $tag, $val );
+                                               $val = $this->exifMsg( $tag, $val );
                                                break;
                                        default:
                                                /* If not recognized, display as is. */
@@ -238,12 +259,12 @@ class FormatMetadata {
                                case 'dc-date':
                                case 'DateTimeMetadata':
                                        if ( $val == '0000:00:00 00:00:00' || $val == '    :  :     :  :  ' ) {
-                                               $val = wfMessage( 'exif-unknowndate' )->text();
+                                               $val = $this->msg( 'exif-unknowndate' )->text();
                                        } elseif ( preg_match( '/^(?:\d{4}):(?:\d\d):(?:\d\d) (?:\d\d):(?:\d\d):(?:\d\d)$/D', $val ) ) {
                                                // Full date.
                                                $time = wfTimestamp( TS_MW, $val );
                                                if ( $time && intval( $time ) > 0 ) {
-                                                       $val = $wgLang->timeanddate( $time );
+                                                       $val = $this->getLanguage()->timeanddate( $time );
                                                }
                                        } elseif ( preg_match( '/^(?:\d{4}):(?:\d\d):(?:\d\d) (?:\d\d):(?:\d\d)$/D', $val ) ) {
                                                // No second field. Still format the same
@@ -251,7 +272,7 @@ class FormatMetadata {
                                                // but second still available in api
                                                $time = wfTimestamp( TS_MW, $val . ':00' );
                                                if ( $time && intval( $time ) > 0 ) {
-                                                       $val = $wgLang->timeanddate( $time );
+                                                       $val = $this->getLanguage()->timeanddate( $time );
                                                }
                                        } elseif ( preg_match( '/^(?:\d{4}):(?:\d\d):(?:\d\d)$/D', $val ) ) {
                                                // If only the date but not the time is filled in.
@@ -260,7 +281,7 @@ class FormatMetadata {
                                                        . substr( $val, 8, 2 )
                                                        . '000000' );
                                                if ( $time && intval( $time ) > 0 ) {
-                                                       $val = $wgLang->date( $time );
+                                                       $val = $this->getLanguage()->date( $time );
                                                }
                                        }
                                        // else it will just output $val without formatting it.
@@ -269,7 +290,7 @@ class FormatMetadata {
                                case 'ExposureProgram':
                                        switch ( $val ) {
                                        case 0: case 1: case 2: case 3: case 4: case 5: case 6: case 7: case 8:
-                                               $val = self::msg( $tag, $val );
+                                               $val = $this->exifMsg( $tag, $val );
                                                break;
                                        default:
                                                /* If not recognized, display as is. */
@@ -278,13 +299,13 @@ class FormatMetadata {
                                        break;
 
                                case 'SubjectDistance':
-                                       $val = self::msg( $tag, '', self::formatNum( $val ) );
+                                       $val = $this->exifMsg( $tag, '', $this->formatNum( $val ) );
                                        break;
 
                                case 'MeteringMode':
                                        switch ( $val ) {
                                        case 0: case 1: case 2: case 3: case 4: case 5: case 6: case 7: case 255:
-                                               $val = self::msg( $tag, $val );
+                                               $val = $this->exifMsg( $tag, $val );
                                                break;
                                        default:
                                                /* If not recognized, display as is. */
@@ -297,7 +318,7 @@ class FormatMetadata {
                                        case 0: case 1: case 2: case 3: case 4: case 9: case 10: case 11:
                                        case 12: case 13: case 14: case 15: case 17: case 18: case 19: case 20:
                                        case 21: case 22: case 23: case 24: case 255:
-                                               $val = self::msg( $tag, $val );
+                                               $val = $this->exifMsg( $tag, $val );
                                                break;
                                        default:
                                                /* If not recognized, display as is. */
@@ -322,15 +343,15 @@ class FormatMetadata {
                                                        continue;
                                                }
                                                $fullTag = $tag . '-' . $subTag;
-                                               $flashMsgs[] = self::msg( $fullTag, $subValue );
+                                               $flashMsgs[] = $this->exifMsg( $fullTag, $subValue );
                                        }
-                                       $val = $wgLang->commaList( $flashMsgs );
+                                       $val = $this->getLanguage()->commaList( $flashMsgs );
                                        break;
 
                                case 'FocalPlaneResolutionUnit':
                                        switch ( $val ) {
                                        case 2:
-                                               $val = self::msg( $tag, $val );
+                                               $val = $this->exifMsg( $tag, $val );
                                                break;
                                        default:
                                                /* If not recognized, display as is. */
@@ -341,7 +362,7 @@ class FormatMetadata {
                                case 'SensingMethod':
                                        switch ( $val ) {
                                        case 1: case 2: case 3: case 4: case 5: case 7: case 8:
-                                               $val = self::msg( $tag, $val );
+                                               $val = $this->exifMsg( $tag, $val );
                                                break;
                                        default:
                                                /* If not recognized, display as is. */
@@ -352,7 +373,7 @@ class FormatMetadata {
                                case 'FileSource':
                                        switch ( $val ) {
                                        case 3:
-                                               $val = self::msg( $tag, $val );
+                                               $val = $this->exifMsg( $tag, $val );
                                                break;
                                        default:
                                                /* If not recognized, display as is. */
@@ -363,7 +384,7 @@ class FormatMetadata {
                                case 'SceneType':
                                        switch ( $val ) {
                                        case 1:
-                                               $val = self::msg( $tag, $val );
+                                               $val = $this->exifMsg( $tag, $val );
                                                break;
                                        default:
                                                /* If not recognized, display as is. */
@@ -374,7 +395,7 @@ class FormatMetadata {
                                case 'CustomRendered':
                                        switch ( $val ) {
                                        case 0: case 1:
-                                               $val = self::msg( $tag, $val );
+                                               $val = $this->exifMsg( $tag, $val );
                                                break;
                                        default:
                                                /* If not recognized, display as is. */
@@ -385,7 +406,7 @@ class FormatMetadata {
                                case 'ExposureMode':
                                        switch ( $val ) {
                                        case 0: case 1: case 2:
-                                               $val = self::msg( $tag, $val );
+                                               $val = $this->exifMsg( $tag, $val );
                                                break;
                                        default:
                                                /* If not recognized, display as is. */
@@ -396,7 +417,7 @@ class FormatMetadata {
                                case 'WhiteBalance':
                                        switch ( $val ) {
                                        case 0: case 1:
-                                               $val = self::msg( $tag, $val );
+                                               $val = $this->exifMsg( $tag, $val );
                                                break;
                                        default:
                                                /* If not recognized, display as is. */
@@ -407,7 +428,7 @@ class FormatMetadata {
                                case 'SceneCaptureType':
                                        switch ( $val ) {
                                        case 0: case 1: case 2: case 3:
-                                               $val = self::msg( $tag, $val );
+                                               $val = $this->exifMsg( $tag, $val );
                                                break;
                                        default:
                                                /* If not recognized, display as is. */
@@ -418,7 +439,7 @@ class FormatMetadata {
                                case 'GainControl':
                                        switch ( $val ) {
                                        case 0: case 1: case 2: case 3: case 4:
-                                               $val = self::msg( $tag, $val );
+                                               $val = $this->exifMsg( $tag, $val );
                                                break;
                                        default:
                                                /* If not recognized, display as is. */
@@ -429,7 +450,7 @@ class FormatMetadata {
                                case 'Contrast':
                                        switch ( $val ) {
                                        case 0: case 1: case 2:
-                                               $val = self::msg( $tag, $val );
+                                               $val = $this->exifMsg( $tag, $val );
                                                break;
                                        default:
                                                /* If not recognized, display as is. */
@@ -440,7 +461,7 @@ class FormatMetadata {
                                case 'Saturation':
                                        switch ( $val ) {
                                        case 0: case 1: case 2:
-                                               $val = self::msg( $tag, $val );
+                                               $val = $this->exifMsg( $tag, $val );
                                                break;
                                        default:
                                                /* If not recognized, display as is. */
@@ -451,7 +472,7 @@ class FormatMetadata {
                                case 'Sharpness':
                                        switch ( $val ) {
                                        case 0: case 1: case 2:
-                                               $val = self::msg( $tag, $val );
+                                               $val = $this->exifMsg( $tag, $val );
                                                break;
                                        default:
                                                /* If not recognized, display as is. */
@@ -462,7 +483,7 @@ class FormatMetadata {
                                case 'SubjectDistanceRange':
                                        switch ( $val ) {
                                        case 0: case 1: case 2: case 3:
-                                               $val = self::msg( $tag, $val );
+                                               $val = $this->exifMsg( $tag, $val );
                                                break;
                                        default:
                                                /* If not recognized, display as is. */
@@ -475,7 +496,7 @@ class FormatMetadata {
                                case 'GPSDestLatitudeRef':
                                        switch ( $val ) {
                                        case 'N': case 'S':
-                                               $val = self::msg( 'GPSLatitude', $val );
+                                               $val = $this->exifMsg( 'GPSLatitude', $val );
                                                break;
                                        default:
                                                /* If not recognized, display as is. */
@@ -487,7 +508,7 @@ class FormatMetadata {
                                case 'GPSDestLongitudeRef':
                                        switch ( $val ) {
                                        case 'E': case 'W':
-                                               $val = self::msg( 'GPSLongitude', $val );
+                                               $val = $this->exifMsg( 'GPSLongitude', $val );
                                                break;
                                        default:
                                                /* If not recognized, display as is. */
@@ -497,16 +518,16 @@ class FormatMetadata {
 
                                case 'GPSAltitude':
                                        if ( $val < 0 ) {
-                                               $val = self::msg( 'GPSAltitude', 'below-sealevel', self::formatNum( -$val, 3 ) );
+                                               $val = $this->exifMsg( 'GPSAltitude', 'below-sealevel', $this->formatNum( -$val, 3 ) );
                                        } else {
-                                               $val = self::msg( 'GPSAltitude', 'above-sealevel', self::formatNum( $val, 3 ) );
+                                               $val = $this->exifMsg( 'GPSAltitude', 'above-sealevel', $this->formatNum( $val, 3 ) );
                                        }
                                        break;
 
                                case 'GPSStatus':
                                        switch ( $val ) {
                                        case 'A': case 'V':
-                                               $val = self::msg( $tag, $val );
+                                               $val = $this->exifMsg( $tag, $val );
                                                break;
                                        default:
                                                /* If not recognized, display as is. */
@@ -517,7 +538,7 @@ class FormatMetadata {
                                case 'GPSMeasureMode':
                                        switch ( $val ) {
                                        case 2: case 3:
-                                               $val = self::msg( $tag, $val );
+                                               $val = $this->exifMsg( $tag, $val );
                                                break;
                                        default:
                                                /* If not recognized, display as is. */
@@ -530,7 +551,7 @@ class FormatMetadata {
                                case 'GPSDestBearingRef':
                                        switch ( $val ) {
                                        case 'T': case 'M':
-                                               $val = self::msg( 'GPSDirection', $val );
+                                               $val = $this->exifMsg( 'GPSDirection', $val );
                                                break;
                                        default:
                                                /* If not recognized, display as is. */
@@ -540,17 +561,17 @@ class FormatMetadata {
 
                                case 'GPSLatitude':
                                case 'GPSDestLatitude':
-                                       $val = self::formatCoords( $val, 'latitude' );
+                                       $val = $this->formatCoords( $val, 'latitude' );
                                        break;
                                case 'GPSLongitude':
                                case 'GPSDestLongitude':
-                                       $val = self::formatCoords( $val, 'longitude' );
+                                       $val = $this->formatCoords( $val, 'longitude' );
                                        break;
 
                                case 'GPSSpeedRef':
                                        switch ( $val ) {
                                        case 'K': case 'M': case 'N':
-                                               $val = self::msg( 'GPSSpeed', $val );
+                                               $val = $this->exifMsg( 'GPSSpeed', $val );
                                                break;
                                        default:
                                                /* If not recognized, display as is. */
@@ -561,7 +582,7 @@ class FormatMetadata {
                                case 'GPSDestDistanceRef':
                                        switch ( $val ) {
                                        case 'K': case 'M': case 'N':
-                                               $val = self::msg( 'GPSDestDistance', $val );
+                                               $val = $this->exifMsg( 'GPSDestDistance', $val );
                                                break;
                                        default:
                                                /* If not recognized, display as is. */
@@ -572,15 +593,15 @@ class FormatMetadata {
                                case 'GPSDOP':
                                        // See http://en.wikipedia.org/wiki/Dilution_of_precision_(GPS)
                                        if ( $val <= 2 ) {
-                                               $val = self::msg( $tag, 'excellent', self::formatNum( $val ) );
+                                               $val = $this->exifMsg( $tag, 'excellent', $this->formatNum( $val ) );
                                        } elseif ( $val <= 5 ) {
-                                               $val = self::msg( $tag, 'good', self::formatNum( $val ) );
+                                               $val = $this->exifMsg( $tag, 'good', $this->formatNum( $val ) );
                                        } elseif ( $val <= 10 ) {
-                                               $val = self::msg( $tag, 'moderate', self::formatNum( $val ) );
+                                               $val = $this->exifMsg( $tag, 'moderate', $this->formatNum( $val ) );
                                        } elseif ( $val <= 20 ) {
-                                               $val = self::msg( $tag, 'fair', self::formatNum( $val ) );
+                                               $val = $this->exifMsg( $tag, 'fair', $this->formatNum( $val ) );
                                        } else {
-                                               $val = self::msg( $tag, 'poor', self::formatNum( $val ) );
+                                               $val = $this->exifMsg( $tag, 'poor', $this->formatNum( $val ) );
                                        }
                                        break;
 
@@ -589,41 +610,41 @@ class FormatMetadata {
                                // the make, model and software name to link to their articles.
                                case 'Make':
                                case 'Model':
-                                       $val = self::msg( $tag, '', $val );
+                                       $val = $this->exifMsg( $tag, '', $val );
                                        break;
 
                                case 'Software':
                                        if ( is_array( $val ) ) {
                                                //if its a software, version array.
-                                               $val = wfMessage( 'exif-software-version-value', $val[0], $val[1] )->text();
+                                               $val = $this->msg( 'exif-software-version-value', $val[0], $val[1] )->text();
                                        } else {
-                                               $val = self::msg( $tag, '', $val );
+                                               $val = $this->exifMsg( $tag, '', $val );
                                        }
                                        break;
 
                                case 'ExposureTime':
                                        // Show the pretty fraction as well as decimal version
-                                       $val = wfMessage( 'exif-exposuretime-format',
-                                               self::formatFraction( $val ), self::formatNum( $val ) )->text();
+                                       $val = $this->msg( 'exif-exposuretime-format',
+                                               $this->formatFraction( $val ), $this->formatNum( $val ) )->text();
                                        break;
                                case 'ISOSpeedRatings':
                                        // If its = 65535 that means its at the
                                        // limit of the size of Exif::short and
                                        // is really higher.
                                        if ( $val == '65535' ) {
-                                               $val = self::msg( $tag, 'overflow' );
+                                               $val = $this->exifMsg( $tag, 'overflow' );
                                        } else {
-                                               $val = self::formatNum( $val );
+                                               $val = $this->formatNum( $val );
                                        }
                                        break;
                                case 'FNumber':
-                                       $val = wfMessage( 'exif-fnumber-format',
-                                               self::formatNum( $val ) )->text();
+                                       $val = $this->msg( 'exif-fnumber-format',
+                                               $this->formatNum( $val ) )->text();
                                        break;
 
                                case 'FocalLength': case 'FocalLengthIn35mmFilm':
-                                       $val = wfMessage( 'exif-focallength-format',
-                                               self::formatNum( $val ) )->text();
+                                       $val = $this->msg( 'exif-focallength-format',
+                                               $this->formatNum( $val ) )->text();
                                        break;
 
                                case 'MaxApertureValue':
@@ -637,9 +658,9 @@ class FormatMetadata {
                                        if ( is_numeric( $val ) ) {
                                                $fNumber = pow( 2, $val / 2 );
                                                if ( $fNumber !== false ) {
-                                                       $val = wfMessage( 'exif-maxaperturevalue-value',
-                                                               self::formatNum( $val ),
-                                                               self::formatNum( $fNumber, 2 )
+                                                       $val = $this->msg( 'exif-maxaperturevalue-value',
+                                                               $this->formatNum( $val ),
+                                                               $this->formatNum( $fNumber, 2 )
                                                        )->text();
                                                }
                                        }
@@ -658,7 +679,7 @@ class FormatMetadata {
                                                case 'sci': case 'soi':
                                                case 'spo': case 'war':
                                                case 'wea':
-                                                       $val = self::msg(
+                                                       $val = $this->exifMsg(
                                                                'iimcategory',
                                                                $val
                                                        );
@@ -670,7 +691,7 @@ class FormatMetadata {
                                        // classification. We decode the
                                        // first 2 digits, which provide
                                        // a broad category.
-                                       $val = self::convertNewsCode( $val );
+                                       $val = $this->convertNewsCode( $val );
                                        break;
                                case 'Urgency':
                                        // 1-8 with 1 being highest, 5 normal
@@ -687,7 +708,7 @@ class FormatMetadata {
                                        }
 
                                        if ( $urgency !== '' ) {
-                                               $val = self::msg( 'urgency',
+                                               $val = $this->exifMsg( 'urgency',
                                                        $urgency, $val
                                                );
                                        }
@@ -700,7 +721,7 @@ class FormatMetadata {
                                case 'PixelYDimension':
                                case 'ImageWidth':
                                case 'ImageLength':
-                                       $val = self::formatNum( $val ) . ' ' . wfMessage( 'unit-pixel' )->text();
+                                       $val = $this->formatNum( $val ) . ' ' . $this->msg( 'unit-pixel' )->text();
                                        break;
 
                                // Do not transform fields with pure text.
@@ -783,7 +804,7 @@ class FormatMetadata {
                                case 'ObjectCycle':
                                        switch ( $val ) {
                                        case 'a': case 'p': case 'b':
-                                               $val = self::msg( $tag, $val );
+                                               $val = $this->exifMsg( $tag, $val );
                                                break;
                                        default:
                                                $val = htmlspecialchars( $val );
@@ -793,20 +814,20 @@ class FormatMetadata {
                                case 'Copyrighted':
                                        switch ( $val ) {
                                        case 'True': case 'False':
-                                               $val = self::msg( $tag, $val );
+                                               $val = $this->exifMsg( $tag, $val );
                                                break;
                                        }
                                        break;
                                case 'Rating':
                                        if ( $val == '-1' ) {
-                                               $val = self::msg( $tag, 'rejected' );
+                                               $val = $this->exifMsg( $tag, 'rejected' );
                                        } else {
-                                               $val = self::formatNum( $val );
+                                               $val = $this->formatNum( $val );
                                        }
                                        break;
 
                                case 'LanguageCode':
-                                       $lang = Language::fetchLanguageName( strtolower( $val ), $wgLang->getCode() );
+                                       $lang = Language::fetchLanguageName( strtolower( $val ), $this->getLanguage()->getCode() );
                                        if ( $lang ) {
                                                $val = htmlspecialchars( $lang );
                                        } else {
@@ -815,17 +836,64 @@ class FormatMetadata {
                                        break;
 
                                default:
-                                       $val = self::formatNum( $val );
+                                       $val = $this->formatNum( $val );
                                        break;
                                }
                        }
                        // End formatting values, start flattening arrays.
-                       $vals = self::flattenArray( $vals, $type );
+                       $vals = $this->flattenArrayReal( $vals, $type );
 
                }
                return $tags;
        }
 
+       /**
+        * Flatten an array, using the content language for any messages.
+        *
+        * @param array $vals array of values
+        * @param string $type Type of array (either lang, ul, ol).
+        *     lang = language assoc array with keys being the lang code
+        *     ul = unordered list, ol = ordered list
+        *     type can also come from the '_type' member of $vals.
+        * @param $noHtml Boolean If to avoid returning anything resembling
+        *     html. (Ugly hack for backwards compatibility with old mediawiki).
+        * @param IContextSource $context
+        * @return String single value (in wiki-syntax).
+        * @since 1.23
+        */
+       public static function flattenArrayContentLang( $vals, $type = 'ul', $noHtml = false, $context = false ) {
+               global $wgContLang;
+               $obj = new FormatMetadata;
+               if ( $context ) {
+                       $obj->setContext( $context );
+               }
+               $context = new DerivativeContext( $obj->getContext() );
+               $context->setLanguage( $wgContLang );
+               $obj->setContext( $context );
+               return $obj->flattenArrayReal( $vals, $type, $noHtml );
+       }
+
+       /**
+        * Flatten an array, using the user language for any messages.
+        *
+        * @param array $vals array of values
+        * @param string $type Type of array (either lang, ul, ol).
+        *     lang = language assoc array with keys being the lang code
+        *     ul = unordered list, ol = ordered list
+        *     type can also come from the '_type' member of $vals.
+        * @param $noHtml Boolean If to avoid returning anything resembling
+        *     html. (Ugly hack for backwards compatibility with old mediawiki).
+        * @param IContextSource $context
+        * @return String single value (in wiki-syntax).
+        */
+       public static function flattenArray( $vals, $type = 'ul', $noHtml = false, $context = false ) {
+               $obj = new FormatMetadata;
+               if ( $context ) {
+                       $obj->setContext( $context );
+               }
+               return $obj->flattenArrayReal( $vals, $type, $noHtml );
+       }
+
        /**
         * A function to collapse multivalued tags into a single value.
         * This turns an array of (for example) authors into a bulleted list.
@@ -834,14 +902,19 @@ class FormatMetadata {
         *
         * @param array $vals array of values
         * @param string $type Type of array (either lang, ul, ol).
-        * lang = language assoc array with keys being the lang code
-        * ul = unordered list, ol = ordered list
-        * type can also come from the '_type' member of $vals.
+        *     lang = language assoc array with keys being the lang code
+        *     ul = unordered list, ol = ordered list
+        *     type can also come from the '_type' member of $vals.
         * @param $noHtml Boolean If to avoid returning anything resembling
-        * html. (Ugly hack for backwards compatibility with old mediawiki).
+        *     html. (Ugly hack for backwards compatibility with old mediawiki).
         * @return String single value (in wiki-syntax).
+        * @since 1.23
         */
-       public static function flattenArray( $vals, $type = 'ul', $noHtml = false ) {
+       public function flattenArrayReal( $vals, $type = 'ul', $noHtml = false ) {
+               if ( !is_array( $vals ) ) {
+                       return $vals; // do nothing if not an array;
+               }
+
                if ( isset( $vals['_type'] ) ) {
                        $type = $vals['_type'];
                        unset( $vals['_type'] );
@@ -895,7 +968,7 @@ class FormatMetadata {
                                                $defaultItem = false;
                                                $isDefault = true;
                                        }
-                                       $content .= self::langItem(
+                                       $content .= $this->langItem(
                                                $vals[$cLang], $cLang,
                                                $isDefault, $noHtml );
 
@@ -908,11 +981,11 @@ class FormatMetadata {
                                                $defaultLang = $lang;
                                                continue;
                                        }
-                                       $content .= self::langItem( $item,
+                                       $content .= $this->langItem( $item,
                                                $lang, false, $noHtml );
                                }
                                if ( $defaultItem !== false ) {
-                                       $content = self::langItem( $defaultItem,
+                                       $content = $this->langItem( $defaultItem,
                                                $defaultLang, true, $noHtml ) .
                                                $content;
                                }
@@ -947,7 +1020,7 @@ class FormatMetadata {
         * @return string language item (Note: despite how this looks,
         * this is treated as wikitext not html).
         */
-       private static function langItem( $value, $lang, $default = false, $noHtml = false ) {
+       private function langItem( $value, $lang, $default = false, $noHtml = false ) {
                if ( $lang === false && $default === false ) {
                        throw new MWException( '$lang and $default cannot both '
                                . 'be false.' );
@@ -961,13 +1034,12 @@ class FormatMetadata {
                }
 
                if ( $lang === false ) {
+                       $msg = $this->msg( 'metadata-langitem-default', $wrappedValue );
                        if ( $noHtml ) {
-                               return wfMessage( 'metadata-langitem-default',
-                                       $wrappedValue )->text() . "\n\n";
+                               return $msg->text() . "\n\n";
                        } /* else */
                        return '<li class="mw-metadata-lang-default">'
-                               . wfMessage( 'metadata-langitem-default',
-                                       $wrappedValue )->text()
+                               . $msg->text()
                                . "</li>\n";
                }
 
@@ -984,9 +1056,9 @@ class FormatMetadata {
                }
                // else we have a language specified
 
+               $msg = $this->msg( 'metadata-langitem', $wrappedValue, $langName, $lang );
                if ( $noHtml ) {
-                       return '*' . wfMessage( 'metadata-langitem',
-                               $wrappedValue, $langName, $lang )->text();
+                       return '*' . $msg->text();
                } /* else: */
 
                $item = '<li class="mw-metadata-lang-code-'
@@ -995,8 +1067,7 @@ class FormatMetadata {
                        $item .= ' mw-metadata-lang-default';
                }
                $item .= '" lang="' . $lang . '">';
-               $item .= wfMessage( 'metadata-langitem',
-                       $wrappedValue, $langName, $lang )->text();
+               $item .= $msg->text();
                $item .= "</li>\n";
                return $item;
        }
@@ -1010,15 +1081,15 @@ class FormatMetadata {
         * @param string $val the value of the tag
         * @param string $arg an argument to pass ($1)
         * @param string $arg2 a 2nd argument to pass ($2)
-        * @return string A wfMessage of "exif-$tag-$val" in lower case
+        * @return string The text content of "exif-$tag-$val" message in lower case
         */
-       static function msg( $tag, $val, $arg = null, $arg2 = null ) {
+       private function exifMsg( $tag, $val, $arg = null, $arg2 = null ) {
                global $wgContLang;
 
                if ( $val === '' ) {
                        $val = 'value';
                }
-               return wfMessage( $wgContLang->lc( "exif-$tag-$val" ), $arg, $arg2 )->text();
+               return $this->msg( $wgContLang->lc( "exif-$tag-$val" ), $arg, $arg2 )->text();
        }
 
        /**
@@ -1029,15 +1100,14 @@ class FormatMetadata {
         * @param $round float|int|bool digits to round to or false.
         * @return mixed A floating point number or whatever we were fed
         */
-       static function formatNum( $num, $round = false ) {
-               global $wgLang;
+       private function formatNum( $num, $round = false ) {
                $m = array();
                if ( is_array( $num ) ) {
                        $out = array();
                        foreach ( $num as $number ) {
-                               $out[] = self::formatNum( $number );
+                               $out[] = $this->formatNum( $number );
                        }
-                       return $wgLang->commaList( $out );
+                       return $this->getLanguage()->commaList( $out );
                }
                if ( preg_match( '/^(-?\d+)\/(\d+)$/', $num, $m ) ) {
                        if ( $m[2] != 0 ) {
@@ -1049,12 +1119,12 @@ class FormatMetadata {
                                $newNum = $num;
                        }
 
-                       return $wgLang->formatNum( $newNum );
+                       return $this->getLanguage()->formatNum( $newNum );
                } else {
                        if ( is_numeric( $num ) && $round !== false ) {
                                $num = round( $num, $round );
                        }
-                       return $wgLang->formatNum( $num );
+                       return $this->getLanguage()->formatNum( $num );
                }
        }
 
@@ -1066,18 +1136,18 @@ class FormatMetadata {
         * @param $num Mixed: the value to format
         * @return mixed A floating point number or whatever we were fed
         */
-       static function formatFraction( $num ) {
+       private function formatFraction( $num ) {
                $m = array();
                if ( preg_match( '/^(-?\d+)\/(\d+)$/', $num, $m ) ) {
                        $numerator = intval( $m[1] );
                        $denominator = intval( $m[2] );
-                       $gcd = self::gcd( abs( $numerator ), $denominator );
+                       $gcd = $this->gcd( abs( $numerator ), $denominator );
                        if ( $gcd != 0 ) {
                                // 0 shouldn't happen! ;)
-                               return self::formatNum( $numerator / $gcd ) . '/' . self::formatNum( $denominator / $gcd );
+                               return $this->formatNum( $numerator / $gcd ) . '/' . $this->formatNum( $denominator / $gcd );
                        }
                }
-               return self::formatNum( $num );
+               return $this->formatNum( $num );
        }
 
        /**
@@ -1088,7 +1158,7 @@ class FormatMetadata {
         * @return int
         * @private
         */
-       static function gcd( $a, $b ) {
+       private function gcd( $a, $b ) {
                /*
                        // http://en.wikipedia.org/wiki/Euclidean_algorithm
                        // Recursive form would be:
@@ -1119,7 +1189,7 @@ class FormatMetadata {
         * @param string $val The 8 digit news code.
         * @return string The human readable form
         */
-       private static function convertNewsCode( $val ) {
+       private function convertNewsCode( $val ) {
                if ( !preg_match( '/^\d{8}$/D', $val ) ) {
                        // Not a valid news code.
                        return $val;
@@ -1179,8 +1249,8 @@ class FormatMetadata {
                                break;
                }
                if ( $cat !== '' ) {
-                       $catMsg = self::msg( 'iimcategory', $cat );
-                       $val = self::msg( 'subjectnewscode', '', $val, $catMsg );
+                       $catMsg = $this->exifMsg( 'iimcategory', $cat );
+                       $val = $this->exifMsg( 'subjectnewscode', '', $val, $catMsg );
                }
                return $val;
        }
@@ -1193,7 +1263,7 @@ class FormatMetadata {
         * @param string $type latitude or longitude (for if its a NWS or E)
         * @return mixed A floating point number or whatever we were fed
         */
-       static function formatCoords( $coord, $type ) {
+       private function formatCoords( $coord, $type ) {
                $ref = '';
                if ( $coord < 0 ) {
                        $nCoord = -$coord;
@@ -1215,11 +1285,11 @@ class FormatMetadata {
                $min = floor( ( $nCoord - $deg ) * 60.0 );
                $sec = round( ( ( $nCoord - $deg ) - $min / 60 ) * 3600, 2 );
 
-               $deg = self::formatNum( $deg );
-               $min = self::formatNum( $min );
-               $sec = self::formatNum( $sec );
+               $deg = $this->formatNum( $deg );
+               $min = $this->formatNum( $min );
+               $sec = $this->formatNum( $sec );
 
-               return wfMessage( 'exif-coordinate-format', $deg, $min, $sec, $ref, $coord )->text();
+               return $this->msg( 'exif-coordinate-format', $deg, $min, $sec, $ref, $coord )->text();
        }
 
        /**
@@ -1235,8 +1305,9 @@ class FormatMetadata {
         * public.
         *
         * @return String of html-ish looking wikitext
+        * @since 1.23 no longer static
         */
-       public static function collapseContactInfo( $vals ) {
+       public function collapseContactInfo( $vals ) {
                if ( !( isset( $vals['CiAdrExtadr'] )
                        || isset( $vals['CiAdrCity'] )
                        || isset( $vals['CiAdrCtry'] )
@@ -1258,7 +1329,7 @@ class FormatMetadata {
                        foreach ( $vals as &$val ) {
                                $val = htmlspecialchars( $val );
                        }
-                       return self::flattenArray( $vals );
+                       return $this->flattenArrayReal( $vals );
                } else {
                        // We have a real ContactInfo field.
                        // Its unclear if all these fields have to be
@@ -1340,11 +1411,238 @@ class FormatMetadata {
                                        . htmlspecialchars( $vals['CiUrlWork'] )
                                        . '</span>';
                        }
-                       return wfMessage( 'exif-contact-value', $email, $url,
+                       return $this->msg( 'exif-contact-value', $email, $url,
                                $street, $city, $region, $postal, $country,
                                $tel )->text();
                }
        }
+
+       /**
+        * Get a list of fields that are visible by default.
+        *
+        * @return array
+        * @since 1.23
+        */
+       public static function getVisibleFields() {
+               $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;
+       }
+
+       /**
+        * Get an array of extended metadata. (See the imageinfo API for format.)
+        *
+        * @param File $file File to use
+        * @return array [<property name> => ['value' => <value>]], or [] on error
+        * @since 1.23
+        */
+       public function fetchExtendedMetadata( File $file ) {
+               global $wgMemc;
+
+               wfProfileIn( __METHOD__ );
+
+               // If revision deleted, exit immediately
+               if ( $file->isDeleted( File::DELETED_FILE ) ) {
+                       return array();
+               }
+
+               $cacheKey = wfMemcKey(
+                       'getExtendedMetadata',
+                       $this->getLanguage()->getCode(),
+                       $file->getSha1()
+               );
+
+               $cachedValue = $wgMemc->get( $cacheKey );
+               if (
+                       $cachedValue
+                       && wfRunHooks( 'ValidateExtendedMetadataCache', array( $cachedValue['timestamp'], $file ) )
+               ) {
+                       $extendedMetadata = $cachedValue['data'];
+               } else {
+                       $maxCacheTime = ( $file instanceof ForeignAPIFile ) ? 60 * 60 * 12 : 60 * 60 * 24 * 30;
+                       $fileMetadata = $this->getExtendedMetadataFromFile( $file );
+                       $extendedMetadata = $this->getExtendedMetadataFromHook( $file, $fileMetadata, $maxCacheTime );
+                       // Make sure the metadata won't break the API when an XML format is used.
+                       // This is an API-specific function so it would be cleaner to call it from
+                       // outside fetchExtendedMetadata, but this way we don't need to redo the
+                       // computation on a cache hit.
+                       $this->sanitizeArrayForXml($extendedMetadata);
+                       $valueToCache = array( 'data' => $extendedMetadata, 'timestamp' => wfTimestampNow() );
+                       $wgMemc->set( $cacheKey, $valueToCache, $maxCacheTime );
+               }
+
+               wfProfileOut( __METHOD__ );
+               return $extendedMetadata;
+       }
+
+       /**
+        * Get file-based metadata in standardized format.
+        *
+        * Note that for a remote file, this might return metadata supplied by extensions.
+        *
+        * @param File $file File to use
+        * @return array [<property name> => ['value' => <value>]], or [] on error
+        * @since 1.23
+        */
+       protected function getExtendedMetadataFromFile( File $file ) {
+               // If this is a remote file accessed via an API request, we already
+               // have remote metadata so we just ignore any local one
+               if ( $file instanceof ForeignAPIFile ) {
+                       // in case of error we pretend no metadata - this will get cached. Might or might not be a good idea.
+                       return $file->getExtendedMetadata() ?: array();
+               }
+
+               wfProfileIn( __METHOD__ );
+
+               $uploadDate = wfTimestamp( TS_ISO_8601, $file->getTimestamp() );
+
+               $fileMetadata = array(
+                       // This is modification time, which is close to "upload" time.
+                       'DateTime' => array(
+                               'value' => $uploadDate,
+                               'source' => 'mediawiki-metadata',
+                       ),
+               );
+
+               $title = $file->getTitle();
+               if ( $title ) {
+                       $text = $title->getText();
+                       $pos = strrpos( $text, '.' );
+
+                       if ( $pos ) {
+                               $name = substr( $text, 0, $pos );
+                       } else {
+                               $name = $text;
+                       }
+
+                       $fileMetadata[ 'ObjectName' ] = array(
+                               'value' => $name,
+                               'source' => 'mediawiki-metadata',
+                       );
+               }
+
+               $common = $file->getCommonMetaArray();
+
+               foreach ( $common as $key => $value ) {
+                       $fileMetadata[$key] = array(
+                               'value' => $value,
+                               'source' => 'file-metadata',
+                       );
+               }
+
+               wfProfileOut( __METHOD__ );
+               return $fileMetadata;
+       }
+
+       /**
+        * Get additional metadata from hooks in standardized format.
+        *
+        * @param File $file File to use
+        * @param array $extendedMetadata
+        * @param int $maxCacheTime hook handlers might use this parameter to override cache time
+        *
+        * @return array [<property name> => ['value' => <value>]], or [] on error
+        * @since 1.23
+        */
+       protected function getExtendedMetadataFromHook( File $file, array $extendedMetadata, &$maxCacheTime ) {
+               wfProfileIn( __METHOD__ );
+
+               wfRunHooks( 'GetExtendedMetadata', array(
+                       &$extendedMetadata,
+                       $file,
+                       $this->getContext(),
+                       &$maxCacheTime
+               ) );
+
+               $visible = array_flip( self::getVisibleFields() );
+               foreach ( $extendedMetadata as $key => $value ) {
+                       if ( !isset( $visible[ strtolower( $key ) ] ) ) {
+                               $extendedMetadata[$key]['hidden'] = '';
+                       }
+               }
+
+               wfProfileOut( __METHOD__ );
+               return $extendedMetadata;
+       }
+
+       /**
+        * Makes sure the given array is a valid API response fragment
+        * (can be transformed into XML)
+        * @param array $arr
+        */
+       protected function sanitizeArrayForXml( &$arr ) {
+               if ( !is_array( $arr ) ) {
+                       return;
+               }
+
+               $counter = 1;
+               foreach ( $arr as $key => &$value ) {
+                       $sanitizedKey = $this->sanitizeKeyForXml( $key );
+                       if ( $sanitizedKey !== $key ) {
+                               if ( isset( $arr[$sanitizedKey] ) ) {
+                                       // Make the sanitized keys hopefully unique.
+                                       // To make it definitely unique would be too much effort, given that
+                                       // sanitizing is only needed for misformatted metadata anyway, but
+                                       // this at least covers the case when $arr is numeric.
+                                       $sanitizedKey .= $counter;
+                                       ++$counter;
+                               }
+                               $arr[$sanitizedKey] = $arr[$key];
+                               unset( $arr[$key] );
+                       }
+                       if ( is_array( $value ) ) {
+                               $this->sanitizeArrayForXml( $value );
+                       }
+               }
+       }
+
+       /**
+        * Turns a string into a valid XML identifier.
+        * Used to ensure that keys of an associative array in the
+        * API response do not break the XML formatter.
+        * @param string $key
+        * @return string
+        * @since 1.23
+        */
+       protected function sanitizeKeyForXml( $key ) {
+               // drop all characters which are not valid in an XML tag name
+               // a bunch of non-ASCII letters would be valid but probably won't
+               // be used so we take the easy way
+               $key = preg_replace( '/[^a-zA-z0-9_:.-]/', '', $key );
+               // drop characters which are invalid at the first position
+               $key = preg_replace( '/^[\d-.]+/', '', $key );
+
+               if ( $key == '' ) {
+                       $key = '_';
+               }
+
+               // special case for an internal keyword
+               if ( $key == '_element' ) {
+                       $key = 'element';
+               }
+
+               return $key;
+       }
+
+       /**
+        * Returns a list of languages (first is best) to use when formatting multilang fields,
+        * based on user and site preferences.
+        * @return array
+        * @since 1.23
+        */
+       protected function getPriorityLanguages()
+       {
+               $priorityLanguages = Language::getFallbacksIncludingSiteLanguage( $this->getLanguage()->getCode() );
+               $priorityLanguages = array_merge( (array) $this->getLanguage()->getCode(), $priorityLanguages[0], $priorityLanguages[1] );
+               return $priorityLanguages;
+       }
 }
 
 /** For compatability with old FormatExif class