info: show XMP history and some other structs via cards

android/app/src/main/kotlin/deckers/thibault/aves/channel/calls/DebugHandler.kt

@@ -14,6 +14,7 @@ import com.drew.imaging.ImageMetadataReader
 import com.drew.metadata.file.FileTypeDirectory
 import deckers.thibault.aves.metadata.ExifInterfaceHelper
 import deckers.thibault.aves.metadata.MediaMetadataRetrieverHelper
+import deckers.thibault.aves.model.provider.FieldMap
 import deckers.thibault.aves.utils.LogUtils
 import deckers.thibault.aves.utils.MimeTypes.isImage
 import deckers.thibault.aves.utils.MimeTypes.isSupportedByExifInterface
@@ -25,6 +26,7 @@ import io.flutter.plugin.common.MethodChannel
 import io.flutter.plugin.common.MethodChannel.MethodCallHandler
 import kotlinx.coroutines.GlobalScope
 import kotlinx.coroutines.launch
+import org.beyka.tiffbitmapfactory.TiffBitmapFactory
 import java.io.IOException
 import java.util.*
 
@@ -38,6 +40,7 @@ class DebugHandler(private val context: Context) : MethodCallHandler {
             "getExifInterfaceMetadata" -> GlobalScope.launch { getExifInterfaceMetadata(call, Coresult(result)) }
             "getMediaMetadataRetrieverMetadata" -> GlobalScope.launch { getMediaMetadataRetrieverMetadata(call, Coresult(result)) }
             "getMetadataExtractorSummary" -> GlobalScope.launch { getMetadataExtractorSummary(call, Coresult(result)) }
+            "getTiffStructure" -> GlobalScope.launch { getTiffStructure(call, Coresult(result)) }
             else -> result.notImplemented()
         }
     }
@@ -226,6 +229,70 @@ class DebugHandler(private val context: Context) : MethodCallHandler {
         result.success(metadataMap)
     }
 
+    private fun getTiffStructure(call: MethodCall, result: MethodChannel.Result) {
+        val uri = call.argument<String>("uri")?.let { Uri.parse(it) }
+        if (uri == null) {
+            result.error("getTiffStructure-args", "failed because of missing arguments", null)
+            return
+        }
+
+        try {
+            val metadataMap = HashMap<String, FieldMap>()
+            var dirCount: Int? = null
+            context.contentResolver.openFileDescriptor(uri, "r")?.use { descriptor ->
+                val options = TiffBitmapFactory.Options().apply {
+                    inJustDecodeBounds = true
+                }
+                TiffBitmapFactory.decodeFileDescriptor(descriptor.fd, options)
+                metadataMap["0"] = tiffOptionsToMap(options)
+                dirCount = options.outDirectoryCount
+            }
+            if (dirCount != null) {
+                for (i in 1 until dirCount!!) {
+                    context.contentResolver.openFileDescriptor(uri, "r")?.use { descriptor ->
+                        val options = TiffBitmapFactory.Options().apply {
+                            inJustDecodeBounds = true
+                            inDirectoryNumber = i
+                        }
+                        TiffBitmapFactory.decodeFileDescriptor(descriptor.fd, options)
+                        metadataMap["$i"] = tiffOptionsToMap(options)
+                    }
+                }
+            }
+            result.success(metadataMap)
+        } catch (e: Exception) {
+            result.error("getTiffStructure-read", "failed to read tiff", e.message)
+        }
+    }
+
+    private fun tiffOptionsToMap(options: TiffBitmapFactory.Options): FieldMap = hashMapOf(
+        "Author" to options.outAuthor,
+        "BitsPerSample" to options.outBitsPerSample.toString(),
+        "CompressionScheme" to options.outCompressionScheme?.toString(),
+        "Copyright" to options.outCopyright,
+        "CurDirectoryNumber" to options.outCurDirectoryNumber.toString(),
+        "Datetime" to options.outDatetime,
+        "DirectoryCount" to options.outDirectoryCount.toString(),
+        "FillOrder" to options.outFillOrder?.toString(),
+        "Height" to options.outHeight.toString(),
+        "HostComputer" to options.outHostComputer,
+        "ImageDescription" to options.outImageDescription,
+        "ImageOrientation" to options.outImageOrientation?.toString(),
+        "NumberOfStrips" to options.outNumberOfStrips.toString(),
+        "Photometric" to options.outPhotometric?.toString(),
+        "PlanarConfig" to options.outPlanarConfig?.toString(),
+        "ResolutionUnit" to options.outResolutionUnit?.toString(),
+        "RowPerStrip" to options.outRowPerStrip.toString(),
+        "SamplePerPixel" to options.outSamplePerPixel.toString(),
+        "Software" to options.outSoftware,
+        "StripSize" to options.outStripSize.toString(),
+        "TileHeight" to options.outTileHeight.toString(),
+        "TileWidth" to options.outTileWidth.toString(),
+        "Width" to options.outWidth.toString(),
+        "XResolution" to options.outXResolution.toString(),
+        "YResolution" to options.outYResolution.toString(),
+    )
+
     companion object {
         private val LOG_TAG = LogUtils.createTag(DebugHandler::class.java)
         const val CHANNEL = "deckers.thibault/aves/debug"

android/app/src/main/kotlin/deckers/thibault/aves/channel/calls/MetadataHandler.kt

@@ -138,6 +138,8 @@ class MetadataHandler(private val context: Context) : MethodCallHandler {
                             } catch (e: XMPException) {
                                 Log.w(LOG_TAG, "failed to read XMP directory for uri=$uri", e)
                             }
+                            // remove this stat as it is not actual XMP data
+                            dirMap.remove(dir.getTagName(XmpDirectory.TAG_XMP_VALUE_COUNT))
                         }
                     }
                 }

lib/model/filters/query.dart

@@ -26,7 +26,7 @@ class QueryFilter extends CollectionFilter {
     // allow untrimmed queries wrapped with `"..."`
     final matches = exactRegex.allMatches(upQuery);
     if (matches.length == 1) {
-      upQuery = matches.elementAt(0).group(1);
+      upQuery = matches.first.group(1);
     }
 
     _filter = not ? (entry) => !entry.search(upQuery) : (entry) => entry.search(upQuery);

lib/ref/mime_types.dart

@@ -1,43 +1,43 @@
 class MimeTypes {
-  static const String anyImage = 'image/*';
+  static const anyImage = 'image/*';
 
-  static const String gif = 'image/gif';
+  static const gif = 'image/gif';
-  static const String heic = 'image/heic';
+  static const heic = 'image/heic';
-  static const String heif = 'image/heif';
+  static const heif = 'image/heif';
-  static const String jpeg = 'image/jpeg';
+  static const jpeg = 'image/jpeg';
-  static const String png = 'image/png';
+  static const png = 'image/png';
-  static const String svg = 'image/svg+xml';
+  static const svg = 'image/svg+xml';
-  static const String webp = 'image/webp';
+  static const webp = 'image/webp';
 
-  static const String tiff = 'image/tiff';
+  static const tiff = 'image/tiff';
-  static const String psd = 'image/vnd.adobe.photoshop';
+  static const psd = 'image/vnd.adobe.photoshop';
 
-  static const String arw = 'image/x-sony-arw';
+  static const arw = 'image/x-sony-arw';
-  static const String cr2 = 'image/x-canon-cr2';
+  static const cr2 = 'image/x-canon-cr2';
-  static const String crw = 'image/x-canon-crw';
+  static const crw = 'image/x-canon-crw';
-  static const String dcr = 'image/x-kodak-dcr';
+  static const dcr = 'image/x-kodak-dcr';
-  static const String dng = 'image/x-adobe-dng';
+  static const dng = 'image/x-adobe-dng';
-  static const String erf = 'image/x-epson-erf';
+  static const erf = 'image/x-epson-erf';
-  static const String k25 = 'image/x-kodak-k25';
+  static const k25 = 'image/x-kodak-k25';
-  static const String kdc = 'image/x-kodak-kdc';
+  static const kdc = 'image/x-kodak-kdc';
-  static const String mrw = 'image/x-minolta-mrw';
+  static const mrw = 'image/x-minolta-mrw';
-  static const String nef = 'image/x-nikon-nef';
+  static const nef = 'image/x-nikon-nef';
-  static const String nrw = 'image/x-nikon-nrw';
+  static const nrw = 'image/x-nikon-nrw';
-  static const String orf = 'image/x-olympus-orf';
+  static const orf = 'image/x-olympus-orf';
-  static const String pef = 'image/x-pentax-pef';
+  static const pef = 'image/x-pentax-pef';
-  static const String raf = 'image/x-fuji-raf';
+  static const raf = 'image/x-fuji-raf';
-  static const String raw = 'image/x-panasonic-raw';
+  static const raw = 'image/x-panasonic-raw';
-  static const String rw2 = 'image/x-panasonic-rw2';
+  static const rw2 = 'image/x-panasonic-rw2';
-  static const String sr2 = 'image/x-sony-sr2';
+  static const sr2 = 'image/x-sony-sr2';
-  static const String srf = 'image/x-sony-srf';
+  static const srf = 'image/x-sony-srf';
-  static const String srw = 'image/x-samsung-srw';
+  static const srw = 'image/x-samsung-srw';
-  static const String x3f = 'image/x-sigma-x3f';
+  static const x3f = 'image/x-sigma-x3f';
 
-  static const String anyVideo = 'video/*';
+  static const anyVideo = 'video/*';
 
-  static const String avi = 'video/avi';
+  static const avi = 'video/avi';
-  static const String mp2t = 'video/mp2t'; // .m2ts
+  static const mp2t = 'video/mp2t'; // .m2ts
-  static const String mp4 = 'video/mp4';
+  static const mp4 = 'video/mp4';
 
   // groups
   static const List<String> rawImages = [arw, cr2, crw, dcr, dng, erf, k25, kdc, mrw, nef, nrw, orf, pef, raf, raw, rw2, sr2, srf, srw, x3f];

lib/services/android_debug_service.dart

@@ -1,4 +1,5 @@
 import 'package:aves/model/image_entry.dart';
+import 'package:aves/ref/mime_types.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter/services.dart';
 
@@ -94,4 +95,18 @@ class AndroidDebugService {
     }
     return {};
   }
+
+  static Future<Map> getTiffStructure(ImageEntry entry) async {
+    if (entry.mimeType != MimeTypes.tiff) return {};
+
+    try {
+      final result = await platform.invokeMethod('getTiffStructure', <String, dynamic>{
+        'uri': entry.uri,
+      }) as Map;
+      return result;
+    } on PlatformException catch (e) {
+      debugPrint('getTiffStructure failed with code=${e.code}, exception=${e.message}, details=${e.details}');
+    }
+    return {};
+  }
 }

lib/theme/durations.dart

@@ -36,6 +36,7 @@ class Durations {
 
   // info
   static const mapStyleSwitchAnimation = Duration(milliseconds: 300);
+  static const xmpStructArrayCardTransition = Duration(milliseconds: 300);
 
   // delays & refresh intervals
   static const opToastDisplay = Duration(seconds: 2);

lib/theme/icons.dart

@@ -26,11 +26,9 @@ class AIcons {
   // actions
   static const IconData addShortcut = Icons.add_to_home_screen_outlined;
   static const IconData clear = Icons.clear_outlined;
-  static const IconData collapse = Icons.expand_less_outlined;
   static const IconData createAlbum = Icons.add_circle_outline;
   static const IconData debug = Icons.whatshot_outlined;
   static const IconData delete = Icons.delete_outlined;
-  static const IconData expand = Icons.expand_more_outlined;
   static const IconData flip = Icons.flip_outlined;
   static const IconData favourite = Icons.favorite_border;
   static const IconData favouriteActive = Icons.favorite;
@@ -52,6 +50,10 @@ class AIcons {
   static const IconData stats = Icons.pie_chart_outlined;
   static const IconData zoomIn = Icons.add_outlined;
   static const IconData zoomOut = Icons.remove_outlined;
+  static const IconData collapse = Icons.expand_less_outlined;
+  static const IconData expand = Icons.expand_more_outlined;
+  static const IconData previous = Icons.chevron_left_outlined;
+  static const IconData next = Icons.chevron_right_outlined;
 
   // albums
   static const IconData album = Icons.photo_album_outlined;

lib/utils/constants.dart

@@ -18,8 +18,8 @@ class Constants {
     offset: Offset(0.5, 1.0),
   );
 
-  static const String overlayUnknown = '—'; // em dash
+  static const overlayUnknown = '—'; // em dash
-  static const String infoUnknown = 'unknown';
+  static const infoUnknown = 'unknown';
 
   static final pointNemo = LatLng(-48.876667, -123.393333);
 

lib/widgets/common/basic/multi_cross_fader.dart

@@ -0,0 +1,57 @@
+import 'package:flutter/material.dart';
+
+class MultiCrossFader extends StatefulWidget {
+  final Duration duration;
+  final Curve fadeCurve, sizeCurve;
+  final AlignmentGeometry alignment;
+  final Widget child;
+
+  const MultiCrossFader({
+    @required this.duration,
+    this.fadeCurve = Curves.linear,
+    this.sizeCurve = Curves.linear,
+    this.alignment = Alignment.topCenter,
+    @required this.child,
+  });
+
+  @override
+  _MultiCrossFaderState createState() => _MultiCrossFaderState();
+}
+
+class _MultiCrossFaderState extends State<MultiCrossFader> {
+  Widget _first, _second;
+  CrossFadeState _fadeState = CrossFadeState.showFirst;
+
+  @override
+  void initState() {
+    super.initState();
+    _first = widget.child;
+    _second = SizedBox();
+  }
+
+  @override
+  void didUpdateWidget(MultiCrossFader oldWidget) {
+    super.didUpdateWidget(oldWidget);
+    if (_first == oldWidget.child) {
+      _second = widget.child;
+      _fadeState = CrossFadeState.showSecond;
+    } else {
+      _first = widget.child;
+      _fadeState = CrossFadeState.showFirst;
+    }
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return AnimatedCrossFade(
+      firstChild: _first,
+      secondChild: _second,
+      firstCurve: widget.fadeCurve,
+      secondCurve: widget.fadeCurve,
+      sizeCurve: widget.sizeCurve,
+      alignment: widget.alignment,
+      crossFadeState: _fadeState,
+      duration: widget.duration,
+    );
+  }
+}

lib/widgets/common/identity/aves_expansion_tile.dart

@@ -30,7 +30,6 @@ class AvesExpansionTile extends StatelessWidget {
         title: HighlightTitle(
           title,
           color: color,
-          fontSize: 18,
           enabled: enabled,
         ),
         expandable: enabled,

lib/widgets/common/identity/highlight_title.dart

@@ -11,7 +11,7 @@ class HighlightTitle extends StatelessWidget {
   const HighlightTitle(
     this.title, {
     this.color,
-    this.fontSize = 20,
+    this.fontSize = 18,
     this.enabled = true,
     this.selectable = false,
   }) : assert(title != null);

lib/widgets/fullscreen/debug/metadata.dart

@@ -2,6 +2,7 @@ import 'dart:collection';
 import 'dart:typed_data';
 
 import 'package:aves/model/image_entry.dart';
+import 'package:aves/ref/mime_types.dart';
 import 'package:aves/services/android_debug_service.dart';
 import 'package:aves/utils/constants.dart';
 import 'package:aves/widgets/common/identity/aves_expansion_tile.dart';
@@ -18,7 +19,7 @@ class MetadataTab extends StatefulWidget {
 }
 
 class _MetadataTabState extends State<MetadataTab> {
-  Future<Map> _bitmapFactoryLoader, _contentResolverMetadataLoader, _exifInterfaceMetadataLoader, _mediaMetadataLoader, _metadataExtractorLoader;
+  Future<Map> _bitmapFactoryLoader, _contentResolverMetadataLoader, _exifInterfaceMetadataLoader, _mediaMetadataLoader, _metadataExtractorLoader, _tiffStructureLoader;
 
   // MediaStore timestamp keys
   static const secondTimestampKeys = ['date_added', 'date_modified', 'date_expires', 'isPlayed'];
@@ -38,15 +39,14 @@ class _MetadataTabState extends State<MetadataTab> {
     _exifInterfaceMetadataLoader = AndroidDebugService.getExifInterfaceMetadata(entry);
     _mediaMetadataLoader = AndroidDebugService.getMediaMetadataRetrieverMetadata(entry);
     _metadataExtractorLoader = AndroidDebugService.getMetadataExtractorSummary(entry);
+    _tiffStructureLoader = AndroidDebugService.getTiffStructure(entry);
     setState(() {});
   }
 
   @override
   Widget build(BuildContext context) {
-    Widget builder(BuildContext context, AsyncSnapshot<Map> snapshot, String title) {
+    Widget builderFromSnapshotData(BuildContext context, Map snapshotData, String title) {
-      if (snapshot.hasError) return Text(snapshot.error.toString());
+      final data = SplayTreeMap.of(snapshotData.map((k, v) {
-      if (snapshot.connectionState != ConnectionState.done) return SizedBox.shrink();
-      final data = SplayTreeMap.of(snapshot.data.map((k, v) {
         final key = k.toString();
         var value = v?.toString() ?? 'null';
         if ([...secondTimestampKeys, ...millisecondTimestampKeys].contains(key) && v is num && v != 0) {
@@ -76,29 +76,47 @@ class _MetadataTabState extends State<MetadataTab> {
       );
     }
 
+    Widget builderFromSnapshot(BuildContext context, AsyncSnapshot<Map> snapshot, String title) {
+      if (snapshot.hasError) return Text(snapshot.error.toString());
+      if (snapshot.connectionState != ConnectionState.done) return SizedBox.shrink();
+      return builderFromSnapshotData(context, snapshot.data, title);
+    }
+
     return ListView(
       padding: EdgeInsets.all(8),
       children: [
         FutureBuilder<Map>(
           future: _bitmapFactoryLoader,
-          builder: (context, snapshot) => builder(context, snapshot, 'Bitmap Factory'),
+          builder: (context, snapshot) => builderFromSnapshot(context, snapshot, 'Bitmap Factory'),
         ),
         FutureBuilder<Map>(
           future: _contentResolverMetadataLoader,
-          builder: (context, snapshot) => builder(context, snapshot, 'Content Resolver'),
+          builder: (context, snapshot) => builderFromSnapshot(context, snapshot, 'Content Resolver'),
         ),
         FutureBuilder<Map>(
           future: _exifInterfaceMetadataLoader,
-          builder: (context, snapshot) => builder(context, snapshot, 'Exif Interface'),
+          builder: (context, snapshot) => builderFromSnapshot(context, snapshot, 'Exif Interface'),
         ),
         FutureBuilder<Map>(
           future: _mediaMetadataLoader,
-          builder: (context, snapshot) => builder(context, snapshot, 'Media Metadata Retriever'),
+          builder: (context, snapshot) => builderFromSnapshot(context, snapshot, 'Media Metadata Retriever'),
         ),
         FutureBuilder<Map>(
           future: _metadataExtractorLoader,
-          builder: (context, snapshot) => builder(context, snapshot, 'Metadata Extractor'),
+          builder: (context, snapshot) => builderFromSnapshot(context, snapshot, 'Metadata Extractor'),
         ),
+        if (entry.mimeType == MimeTypes.tiff)
+          FutureBuilder<Map>(
+            future: _tiffStructureLoader,
+            builder: (context, snapshot) {
+              if (snapshot.hasError) return Text(snapshot.error.toString());
+              if (snapshot.connectionState != ConnectionState.done) return SizedBox.shrink();
+              return Column(
+                crossAxisAlignment: CrossAxisAlignment.start,
+                children: snapshot.data.entries.map((kv) => builderFromSnapshotData(context, kv.value as Map, 'TIFF ${kv.key}')).toList(),
+              );
+            },
+          ),
       ],
     );
   }

lib/widgets/fullscreen/info/metadata/metadata_section.dart

@@ -86,37 +86,42 @@ class _MetadataSectionSliverState extends State<MetadataSectionSliver> with Auto
     // warning: placing the `AnimationLimiter` as a parent to the `ScrollView`
     // triggers dispose & reinitialization of other sections, including heavy widgets like maps
     return SliverToBoxAdapter(
-      child: AnimatedBuilder(
+      child: NotificationListener<ScrollNotification>(
-        animation: _loadedMetadataUri,
+        // cancel notification bubbling so that the info page
-        builder: (context, child) {
+        // does not misinterpret content scrolling for page scrolling
-          Widget content;
+        onNotification: (notification) => true,
-          if (_metadata.isEmpty) {
+        child: AnimatedBuilder(
-            content = SizedBox.shrink();
+          animation: _loadedMetadataUri,
-          } else {
+          builder: (context, child) {
-            content = Column(
+            Widget content;
-              children: AnimationConfiguration.toStaggeredList(
+            if (_metadata.isEmpty) {
-                duration: Durations.staggeredAnimation,
+              content = SizedBox.shrink();
-                delay: Durations.staggeredAnimationDelay,
+            } else {
-                childAnimationBuilder: (child) => SlideAnimation(
+              content = Column(
-                  verticalOffset: 50.0,
+                children: AnimationConfiguration.toStaggeredList(
-                  child: FadeInAnimation(
+                  duration: Durations.staggeredAnimation,
-                    child: child,
+                  delay: Durations.staggeredAnimationDelay,
+                  childAnimationBuilder: (child) => SlideAnimation(
+                    verticalOffset: 50.0,
+                    child: FadeInAnimation(
+                      child: child,
+                    ),
                   ),
+                  children: [
+                    SectionRow(AIcons.info),
+                    ..._metadata.entries.map((kv) => _buildDirTile(kv.key, kv.value)),
+                  ],
                 ),
-                children: [
+              );
-                  SectionRow(AIcons.info),
+            }
-                  ..._metadata.entries.map((kv) => _buildDirTile(kv.key, kv.value)),
+            return AnimationLimiter(
-                ],
+              // we update the limiter key after fetching the metadata of a new entry,
-              ),
+              // in order to restart the staggered animation of the metadata section
+              key: Key(_loadedMetadataUri.value),
+              child: content,
             );
-          }
+          },
-          return AnimationLimiter(
+        ),
-            // we update the limiter key after fetching the metadata of a new entry,
-            // in order to restart the staggered animation of the metadata section
-            key: Key(_loadedMetadataUri.value),
-            child: content,
-          );
-        },
       ),
     );
   }

lib/widgets/fullscreen/info/metadata/xmp_namespaces.dart

@@ -0,0 +1,218 @@
+import 'package:aves/ref/brand_colors.dart';
+import 'package:aves/ref/xmp.dart';
+import 'package:aves/utils/constants.dart';
+import 'package:aves/widgets/common/identity/highlight_title.dart';
+import 'package:aves/widgets/fullscreen/info/common.dart';
+import 'package:aves/widgets/fullscreen/info/metadata/xmp_structs.dart';
+import 'package:collection/collection.dart';
+import 'package:flutter/foundation.dart';
+import 'package:flutter/material.dart';
+
+class XmpNamespace {
+  final String namespace;
+
+  const XmpNamespace(this.namespace);
+
+  String get displayTitle => XMP.namespaces[namespace] ?? namespace;
+
+  List<Widget> buildNamespaceSection({
+    @required List<MapEntry<String, String>> props,
+    @required void Function(String propPath) openEmbeddedData,
+  }) {
+    final linkHandlers = <String, InfoLinkHandler>{};
+
+    final entries = props
+        .map((prop) {
+          final propPath = prop.key;
+          final value = formatValue(prop.value);
+          if (extractData(propPath, value)) return null;
+
+          final displayKey = _formatKey(propPath);
+          if (XMP.dataProps.contains(propPath)) {
+            linkHandlers.putIfAbsent(
+              displayKey,
+              () => InfoLinkHandler(linkText: 'Open', onTap: () => openEmbeddedData(propPath)),
+            );
+          }
+          return MapEntry(displayKey, value);
+        })
+        .where((e) => e != null)
+        .toList()
+          ..sort((a, b) => compareAsciiUpperCaseNatural(a.key, b.key));
+
+    final content = [
+      if (entries.isNotEmpty)
+        InfoRowGroup(
+          Map.fromEntries(entries),
+          maxValueLength: Constants.infoGroupMaxValueLength,
+          linkHandlers: linkHandlers,
+        ),
+      ...buildFromExtractedData(),
+    ];
+
+    return content.isNotEmpty
+        ? [
+            if (displayTitle.isNotEmpty)
+              Padding(
+                padding: EdgeInsets.only(top: 8),
+                child: HighlightTitle(
+                  displayTitle,
+                  color: BrandColors.get(displayTitle),
+                  selectable: true,
+                ),
+              ),
+            ...content
+          ]
+        : [];
+  }
+
+  String _formatKey(String propPath) {
+    return propPath.splitMapJoin(XMP.structFieldSeparator, onNonMatch: (s) {
+      // strip namespace
+      final key = s.split(XMP.propNamespaceSeparator).last;
+      // uppercase first letter
+      return key.replaceFirstMapped(RegExp('.'), (m) => m.group(0).toUpperCase());
+    });
+  }
+
+  bool _extractStruct(String propPath, String value, RegExp pattern, Map<String, String> store) {
+    final matches = pattern.allMatches(propPath);
+    if (matches.isEmpty) return false;
+
+    final match = matches.first;
+    final field = _formatKey(match.group(1));
+    store[field] = value;
+    return true;
+  }
+
+  bool _extractIndexedStruct(String propPath, String value, RegExp pattern, Map<int, Map<String, String>> store) {
+    final matches = pattern.allMatches(propPath);
+    if (matches.isEmpty) return false;
+
+    final match = matches.first;
+    final index = int.parse(match.group(1));
+    final field = _formatKey(match.group(2));
+    final fields = store.putIfAbsent(index, () => <String, String>{});
+    fields[field] = value;
+    return true;
+  }
+
+  bool extractData(String propPath, String value) => false;
+
+  List<Widget> buildFromExtractedData() => [];
+
+  String formatValue(String value) => value;
+
+  // identity
+
+  @override
+  bool operator ==(Object other) {
+    if (other.runtimeType != runtimeType) return false;
+    return other is XmpNamespace && other.namespace == namespace;
+  }
+
+  @override
+  int get hashCode => namespace.hashCode;
+
+  @override
+  String toString() {
+    return '$runtimeType#${shortHash(this)}{namespace=$namespace}';
+  }
+}
+
+class XmpBasicNamespace extends XmpNamespace {
+  static const ns = 'xmp';
+
+  static final thumbnailsPattern = RegExp(r'xmp:Thumbnails\[(\d+)\]/(.*)');
+
+  final thumbnails = <int, Map<String, String>>{};
+
+  XmpBasicNamespace() : super(ns);
+
+  @override
+  bool extractData(String propPath, String value) => _extractIndexedStruct(propPath, value, thumbnailsPattern, thumbnails);
+
+  @override
+  List<Widget> buildFromExtractedData() => [
+        if (thumbnails.isNotEmpty)
+          XmpStructArrayCard(
+            title: 'Thumbnail',
+            structByIndex: thumbnails,
+          )
+      ];
+}
+
+class XmpIptcCoreNamespace extends XmpNamespace {
+  static const ns = 'Iptc4xmpCore';
+
+  static final creatorContactInfoPattern = RegExp(r'Iptc4xmpCore:CreatorContactInfo/(.*)');
+
+  final creatorContactInfo = <String, String>{};
+
+  XmpIptcCoreNamespace() : super(ns);
+
+  @override
+  bool extractData(String propPath, String value) => _extractStruct(propPath, value, creatorContactInfoPattern, creatorContactInfo);
+
+  @override
+  List<Widget> buildFromExtractedData() => [
+        if (creatorContactInfo.isNotEmpty)
+          XmpStructCard(
+            title: 'Creator Contact Info',
+            struct: creatorContactInfo,
+          ),
+      ];
+}
+
+class XmpMMNamespace extends XmpNamespace {
+  static const ns = 'xmpMM';
+
+  static const didPrefix = 'xmp.did:';
+  static const iidPrefix = 'xmp.iid:';
+
+  static final derivedFromPattern = RegExp(r'xmpMM:DerivedFrom/(.*)');
+  static final historyPattern = RegExp(r'xmpMM:History\[(\d+)\]/(.*)');
+
+  final derivedFrom = <String, String>{};
+  final history = <int, Map<String, String>>{};
+
+  XmpMMNamespace() : super(ns);
+
+  @override
+  bool extractData(String propPath, String value) => _extractStruct(propPath, value, derivedFromPattern, derivedFrom) || _extractIndexedStruct(propPath, value, historyPattern, history);
+
+  @override
+  List<Widget> buildFromExtractedData() => [
+        if (derivedFrom.isNotEmpty)
+          XmpStructCard(
+            title: 'Derived From',
+            struct: derivedFrom,
+          ),
+        if (history.isNotEmpty)
+          XmpStructArrayCard(
+            title: 'History',
+            structByIndex: history,
+          ),
+      ];
+
+  @override
+  String formatValue(String value) {
+    if (value.startsWith(didPrefix)) return value.replaceFirst(didPrefix, '');
+    if (value.startsWith(iidPrefix)) return value.replaceFirst(iidPrefix, '');
+    return value;
+  }
+}
+
+class XmpNoteNamespace extends XmpNamespace {
+  static const ns = 'xmpNote';
+
+  // `xmpNote:HasExtendedXMP` is structural and should not be displayed to users
+  static const hasExtendedXmp = '$ns:HasExtendedXMP';
+
+  XmpNoteNamespace() : super(ns);
+
+  @override
+  bool extractData(String propPath, String value) {
+    return propPath == hasExtendedXmp;
+  }
+}

lib/widgets/fullscreen/info/metadata/xmp_structs.dart

@@ -0,0 +1,135 @@
+import 'dart:math';
+
+import 'package:aves/theme/durations.dart';
+import 'package:aves/theme/icons.dart';
+import 'package:aves/utils/constants.dart';
+import 'package:aves/widgets/common/basic/multi_cross_fader.dart';
+import 'package:aves/widgets/common/identity/highlight_title.dart';
+import 'package:aves/widgets/fullscreen/info/common.dart';
+import 'package:flutter/material.dart';
+
+class XmpStructArrayCard extends StatefulWidget {
+  final String title;
+  final List<Map<String, String>> structs = [];
+
+  XmpStructArrayCard({
+    @required this.title,
+    @required Map<int, Map<String, String>> structByIndex,
+  }) {
+    structs.length = structByIndex.keys.fold(0, max);
+    structByIndex.keys.forEach((index) => structs[index - 1] = structByIndex[index]);
+  }
+
+  @override
+  _XmpStructArrayCardState createState() => _XmpStructArrayCardState();
+}
+
+class _XmpStructArrayCardState extends State<XmpStructArrayCard> {
+  int _index;
+
+  List<Map<String, String>> get structs => widget.structs;
+
+  @override
+  void initState() {
+    super.initState();
+    _index = structs.length - 1;
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    void setIndex(int index) {
+      index = index.clamp(0, structs.length - 1);
+      if (_index != index) {
+        _index = index;
+        setState(() {});
+      }
+    }
+
+    return Card(
+      margin: XmpStructCard.cardMargin,
+      child: Column(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          Padding(
+            padding: EdgeInsets.only(left: 8, top: 8, right: 8),
+            child: Row(
+              crossAxisAlignment: CrossAxisAlignment.center,
+              children: [
+                Flexible(
+                  child: HighlightTitle(
+                    '${widget.title} ${_index + 1}',
+                    color: Colors.transparent,
+                    selectable: true,
+                  ),
+                ),
+                IconButton(
+                  visualDensity: VisualDensity.compact,
+                  icon: Icon(AIcons.previous),
+                  onPressed: _index > 0 ? () => setIndex(_index - 1) : null,
+                  tooltip: 'Previous',
+                ),
+                IconButton(
+                  visualDensity: VisualDensity.compact,
+                  icon: Icon(AIcons.next),
+                  onPressed: _index < structs.length - 1 ? () => setIndex(_index + 1) : null,
+                  tooltip: 'Next',
+                ),
+              ],
+            ),
+          ),
+          MultiCrossFader(
+            duration: Durations.xmpStructArrayCardTransition,
+            sizeCurve: Curves.easeOutBack,
+            alignment: AlignmentDirectional.topStart,
+            child: Padding(
+              // add padding at this level (instead of the column level)
+              // so that the crossfader can animate the content size
+              // without clipping the text
+              padding: EdgeInsets.only(left: 8, right: 8, bottom: 8),
+              child: InfoRowGroup(
+                structs[_index],
+                maxValueLength: Constants.infoGroupMaxValueLength,
+              ),
+            ),
+          ),
+        ],
+      ),
+    );
+  }
+}
+
+class XmpStructCard extends StatelessWidget {
+  final String title;
+  final Map<String, String> struct;
+
+  static const cardMargin = EdgeInsets.symmetric(vertical: 8, horizontal: 0);
+
+  const XmpStructCard({
+    @required this.title,
+    @required this.struct,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    return Card(
+      margin: cardMargin,
+      child: Padding(
+        padding: EdgeInsets.all(8),
+        child: Column(
+          crossAxisAlignment: CrossAxisAlignment.start,
+          children: [
+            HighlightTitle(
+              title,
+              color: Colors.transparent,
+              selectable: true,
+            ),
+            InfoRowGroup(
+              struct,
+              maxValueLength: Constants.infoGroupMaxValueLength,
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+}

lib/widgets/fullscreen/info/metadata/xmp_tile.dart

@@ -1,22 +1,18 @@
 import 'dart:collection';
 
 import 'package:aves/model/image_entry.dart';
-import 'package:aves/ref/brand_colors.dart';
 import 'package:aves/ref/mime_types.dart';
 import 'package:aves/ref/xmp.dart';
 import 'package:aves/services/android_app_service.dart';
 import 'package:aves/services/metadata_service.dart';
-import 'package:aves/utils/constants.dart';
 import 'package:aves/widgets/common/action_mixins/feedback.dart';
 import 'package:aves/widgets/common/behaviour/routes.dart';
 import 'package:aves/widgets/common/identity/aves_expansion_tile.dart';
-import 'package:aves/widgets/common/identity/highlight_title.dart';
 import 'package:aves/widgets/dialogs/aves_dialog.dart';
 import 'package:aves/widgets/fullscreen/fullscreen_page.dart';
-import 'package:aves/widgets/fullscreen/info/common.dart';
 import 'package:aves/widgets/fullscreen/info/metadata/metadata_thumbnail.dart';
+import 'package:aves/widgets/fullscreen/info/metadata/xmp_namespaces.dart';
 import 'package:collection/collection.dart';
-import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 import 'package:pedantic/pedantic.dart';
 
@@ -41,13 +37,23 @@ class _XmpDirTileState extends State<XmpDirTile> with FeedbackMixin {
   @override
   Widget build(BuildContext context) {
     final thumbnail = MetadataThumbnails(source: MetadataThumbnailSource.xmp, entry: entry);
-    final sections = SplayTreeMap<_XmpNamespace, List<MapEntry<String, String>>>.of(
+    final sections = SplayTreeMap<XmpNamespace, List<MapEntry<String, String>>>.of(
       groupBy(widget.tags.entries, (kv) {
         final fullKey = kv.key;
         final i = fullKey.indexOf(XMP.propNamespaceSeparator);
-        if (i == -1) return _XmpNamespace('');
+        final namespace = i == -1 ? '' : fullKey.substring(0, i);
-        final namespace = fullKey.substring(0, i);
+        switch (namespace) {
-        return _XmpNamespace(namespace);
+          case XmpBasicNamespace.ns:
+            return XmpBasicNamespace();
+          case XmpIptcCoreNamespace.ns:
+            return XmpIptcCoreNamespace();
+          case XmpMMNamespace.ns:
+            return XmpMMNamespace();
+          case XmpNoteNamespace.ns:
+            return XmpNoteNamespace();
+          default:
+            return XmpNamespace(namespace);
+        }
       }),
       (a, b) => compareAsciiUpperCase(a.displayTitle, b.displayTitle),
     );
@@ -60,48 +66,12 @@ class _XmpDirTileState extends State<XmpDirTile> with FeedbackMixin {
           padding: EdgeInsets.only(left: 8, right: 8, bottom: 8),
           child: Column(
             crossAxisAlignment: CrossAxisAlignment.start,
-            children: sections.entries.expand((namespaceProps) {
+            children: sections.entries
-              final namespace = namespaceProps.key;
+                .expand((kv) => kv.key.buildNamespaceSection(
-              final displayNamespace = namespace.displayTitle;
+                      props: kv.value,
-              final linkHandlers = <String, InfoLinkHandler>{};
+                      openEmbeddedData: _openEmbeddedData,
-
+                    ))
-              final entries = namespaceProps.value.map((prop) {
+                .toList(),
-                final propPath = prop.key;
-
-                final displayKey = propPath.splitMapJoin(XMP.structFieldSeparator, onNonMatch: (s) {
-                  // strip namespace
-                  final key = s.split(XMP.propNamespaceSeparator).last;
-                  // uppercase first letter
-                  return key.replaceFirstMapped(RegExp('.'), (m) => m.group(0).toUpperCase());
-                });
-
-                var value = prop.value;
-                if (XMP.dataProps.contains(propPath)) {
-                  linkHandlers.putIfAbsent(
-                    displayKey,
-                    () => InfoLinkHandler(linkText: 'Open', onTap: () => _openEmbeddedData(propPath)),
-                  );
-                }
-                return MapEntry(displayKey, value);
-              }).toList()
-                ..sort((a, b) => compareAsciiUpperCaseNatural(a.key, b.key));
-              return [
-                if (displayNamespace.isNotEmpty)
-                  Padding(
-                    padding: EdgeInsets.only(top: 8),
-                    child: HighlightTitle(
-                      displayNamespace,
-                      color: BrandColors.get(displayNamespace),
-                      selectable: true,
-                    ),
-                  ),
-                InfoRowGroup(
-                  Map.fromEntries(entries),
-                  maxValueLength: Constants.infoGroupMaxValueLength,
-                  linkHandlers: linkHandlers,
-                ),
-              ];
-            }).toList(),
           ),
         ),
       ],
@@ -140,25 +110,3 @@ class _XmpDirTileState extends State<XmpDirTile> with FeedbackMixin {
     ));
   }
 }
-
-class _XmpNamespace {
-  final String namespace;
-
-  const _XmpNamespace(this.namespace);
-
-  String get displayTitle => XMP.namespaces[namespace] ?? namespace;
-
-  @override
-  bool operator ==(Object other) {
-    if (other.runtimeType != runtimeType) return false;
-    return other is _XmpNamespace && other.namespace == namespace;
-  }
-
-  @override
-  int get hashCode => namespace.hashCode;
-
-  @override
-  String toString() {
-    return '$runtimeType#${shortHash(this)}{namespace=$namespace}';
-  }
-}

lib/widgets/settings/settings_page.dart

@@ -5,7 +5,6 @@ import 'package:aves/model/settings/settings.dart';
 import 'package:aves/theme/durations.dart';
 import 'package:aves/utils/constants.dart';
 import 'package:aves/widgets/common/identity/aves_expansion_tile.dart';
-import 'package:aves/widgets/common/identity/highlight_title.dart';
 import 'package:aves/widgets/common/providers/media_query_data_provider.dart';
 import 'package:aves/widgets/dialogs/aves_selection_dialog.dart';
 import 'package:aves/widgets/settings/access_grants.dart';
@@ -225,17 +224,3 @@ class _SettingsPageState extends State<SettingsPage> {
     );
   }
 }
-
-class SectionTitle extends StatelessWidget {
-  final String text;
-
-  const SectionTitle(this.text);
-
-  @override
-  Widget build(BuildContext context) {
-    return Padding(
-      padding: EdgeInsets.only(left: 16, top: 6, right: 16, bottom: 12),
-      child: HighlightTitle(text),
-    );
-  }
-}