#706 viewer: improved overlay field fetch

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

@@ -109,7 +109,7 @@ class MetadataFetchHandler(private val context: Context) : MethodCallHandler {
         when (call.method) {
             "getAllMetadata" -> ioScope.launch { safe(call, result, ::getAllMetadata) }
             "getCatalogMetadata" -> ioScope.launch { safe(call, result, ::getCatalogMetadata) }
-            "getOverlayMetadata" -> ioScope.launch { safe(call, result, ::getOverlayMetadata) }
+            "getFields" -> ioScope.launch { safe(call, result, ::getFields) }
             "getGeoTiffInfo" -> ioScope.launch { safe(call, result, ::getGeoTiffInfo) }
             "getMultiPageInfo" -> ioScope.launch { safe(call, result, ::getMultiPageInfo) }
             "getPanoramaInfo" -> ioScope.launch { safe(call, result, ::getPanoramaInfo) }
@@ -118,7 +118,6 @@ class MetadataFetchHandler(private val context: Context) : MethodCallHandler {
             "hasContentResolverProp" -> ioScope.launch { safe(call, result, ::hasContentProp) }
             "getContentResolverProp" -> ioScope.launch { safe(call, result, ::getContentPropValue) }
             "getDate" -> ioScope.launch { safe(call, result, ::getDate) }
-            "getDescription" -> ioScope.launch { safe(call, result, ::getDescription) }
             else -> result.notImplemented()
         }
     }
@@ -807,17 +806,18 @@ class MetadataFetchHandler(private val context: Context) : MethodCallHandler {
         }
     }
 
-    private fun getOverlayMetadata(call: MethodCall, result: MethodChannel.Result) {
+    private fun getFields(call: MethodCall, result: MethodChannel.Result) {
         val mimeType = call.argument<String>("mimeType")
         val uri = call.argument<String>("uri")?.let { Uri.parse(it) }
         val sizeBytes = call.argument<Number>("sizeBytes")?.toLong()
-        if (mimeType == null || uri == null) {
+        val fields = call.argument<List<String>>("fields")
+        if (mimeType == null || uri == null || fields == null) {
             result.error("getOverlayMetadata-args", "missing arguments", null)
             return
         }
 
         val metadataMap = HashMap<String, Any>()
-        if (isVideo(mimeType)) {
+        if (fields.isEmpty() || isVideo(mimeType)) {
             result.success(metadataMap)
             return
         }
@@ -842,12 +842,23 @@ class MetadataFetchHandler(private val context: Context) : MethodCallHandler {
                     val metadata = Helper.safeRead(input)
                     for (dir in metadata.getDirectoriesOfType(ExifSubIFDDirectory::class.java)) {
                         foundExif = true
+                        if (fields.contains(KEY_APERTURE)) {
                             dir.getSafeRational(ExifDirectoryBase.TAG_FNUMBER) { metadataMap[KEY_APERTURE] = it.numerator.toDouble() / it.denominator }
+                        }
+                        if (fields.contains(KEY_DESCRIPTION)) {
+                            getDescriptionByMetadataExtractor(metadata)?.let { metadataMap[KEY_DESCRIPTION] = it }
+                        }
+                        if (fields.contains(KEY_EXPOSURE_TIME)) {
                             dir.getSafeRational(ExifDirectoryBase.TAG_EXPOSURE_TIME, saveExposureTime)
+                        }
+                        if (fields.contains(KEY_FOCAL_LENGTH)) {
                             dir.getSafeRational(ExifDirectoryBase.TAG_FOCAL_LENGTH) { metadataMap[KEY_FOCAL_LENGTH] = it.numerator.toDouble() / it.denominator }
+                        }
+                        if (fields.contains(KEY_ISO)) {
                             dir.getSafeInt(ExifDirectoryBase.TAG_ISO_EQUIVALENT) { metadataMap[KEY_ISO] = it }
                         }
                     }
+                }
             } catch (e: Exception) {
                 Log.w(LOG_TAG, "failed to read metadata by metadata-extractor for mimeType=$mimeType uri=$uri", e)
             } catch (e: NoClassDefFoundError) {
@@ -862,11 +873,19 @@ class MetadataFetchHandler(private val context: Context) : MethodCallHandler {
             try {
                 Metadata.openSafeInputStream(context, uri, mimeType, sizeBytes)?.use { input ->
                     val exif = ExifInterface(input)
+                    if (fields.contains(KEY_APERTURE)) {
                         exif.getSafeDouble(ExifInterface.TAG_F_NUMBER) { metadataMap[KEY_APERTURE] = it }
+                    }
+                    if (fields.contains(KEY_EXPOSURE_TIME)) {
                         exif.getSafeRational(ExifInterface.TAG_EXPOSURE_TIME, saveExposureTime)
+                    }
+                    if (fields.contains(KEY_FOCAL_LENGTH)) {
                         exif.getSafeDouble(ExifInterface.TAG_FOCAL_LENGTH) { metadataMap[KEY_FOCAL_LENGTH] = it }
+                    }
+                    if (fields.contains(KEY_ISO)) {
                         exif.getSafeInt(ExifInterface.TAG_PHOTOGRAPHIC_SENSITIVITY) { metadataMap[KEY_ISO] = it }
                     }
+                }
             } catch (e: Exception) {
                 // ExifInterface initialization can fail with a RuntimeException
                 // caused by an internal MediaMetadataRetriever failure
@@ -877,6 +896,47 @@ class MetadataFetchHandler(private val context: Context) : MethodCallHandler {
         result.success(metadataMap)
     }
 
+    // return description from these fields (by precedence):
+    // - XMP / dc:description
+    // - IPTC / caption-abstract
+    // - Exif / UserComment
+    // - Exif / ImageDescription
+    private fun getDescriptionByMetadataExtractor(metadata: com.drew.metadata.Metadata): String? {
+        var description: String? = null
+        for (dir in metadata.getDirectoriesOfType(XmpDirectory::class.java)) {
+            val xmpMeta = dir.xmpMeta
+            try {
+                if (xmpMeta.doesPropExist(XMP.DC_DESCRIPTION_PROP_NAME)) {
+                    xmpMeta.getSafeLocalizedText(XMP.DC_DESCRIPTION_PROP_NAME, acceptBlank = false) { description = it }
+                }
+            } catch (e: XMPException) {
+                Log.w(LOG_TAG, "failed to read XMP directory", e)
+            }
+        }
+        if (description == null) {
+            for (dir in metadata.getDirectoriesOfType(IptcDirectory::class.java)) {
+                dir.getSafeString(IptcDirectory.TAG_CAPTION, acceptBlank = false) { description = it }
+            }
+        }
+        if (description == null) {
+            for (dir in metadata.getDirectoriesOfType(ExifSubIFDDirectory::class.java)) {
+                // user comment field specifies encoding, unlike other string fields
+                if (dir.containsTag(ExifSubIFDDirectory.TAG_USER_COMMENT)) {
+                    val string = dir.getDescription(ExifSubIFDDirectory.TAG_USER_COMMENT)
+                    if (string.isNotBlank()) {
+                        description = string
+                    }
+                }
+            }
+        }
+        if (description == null) {
+            for (dir in metadata.getDirectoriesOfType(ExifIFD0Directory::class.java)) {
+                dir.getSafeString(ExifIFD0Directory.TAG_IMAGE_DESCRIPTION, acceptBlank = false) { description = it }
+            }
+        }
+        return description
+    }
+
     private fun getGeoTiffInfo(call: MethodCall, result: MethodChannel.Result) {
         val mimeType = call.argument<String>("mimeType")
         val uri = call.argument<String>("uri")?.let { Uri.parse(it) }
@@ -1191,70 +1251,6 @@ class MetadataFetchHandler(private val context: Context) : MethodCallHandler {
         result.success(dateMillis)
     }
 
-    // return description from these fields (by precedence):
-    // - XMP / dc:description
-    // - IPTC / caption-abstract
-    // - Exif / UserComment
-    // - Exif / ImageDescription
-    private fun getDescription(call: MethodCall, result: MethodChannel.Result) {
-        val mimeType = call.argument<String>("mimeType")
-        val uri = call.argument<String>("uri")?.let { Uri.parse(it) }
-        val sizeBytes = call.argument<Number>("sizeBytes")?.toLong()
-        if (mimeType == null || uri == null) {
-            result.error("getDescription-args", "missing arguments", null)
-            return
-        }
-
-        var description: String? = null
-        if (canReadWithMetadataExtractor(mimeType)) {
-            try {
-                Metadata.openSafeInputStream(context, uri, mimeType, sizeBytes)?.use { input ->
-                    val metadata = Helper.safeRead(input)
-
-                    for (dir in metadata.getDirectoriesOfType(XmpDirectory::class.java)) {
-                        val xmpMeta = dir.xmpMeta
-                        try {
-                            if (xmpMeta.doesPropExist(XMP.DC_DESCRIPTION_PROP_NAME)) {
-                                xmpMeta.getSafeLocalizedText(XMP.DC_DESCRIPTION_PROP_NAME, acceptBlank = false) { description = it }
-                            }
-                        } catch (e: XMPException) {
-                            Log.w(LOG_TAG, "failed to read XMP directory for uri=$uri", e)
-                        }
-                    }
-                    if (description == null) {
-                        for (dir in metadata.getDirectoriesOfType(IptcDirectory::class.java)) {
-                            dir.getSafeString(IptcDirectory.TAG_CAPTION, acceptBlank = false) { description = it }
-                        }
-                    }
-                    if (description == null) {
-                        for (dir in metadata.getDirectoriesOfType(ExifSubIFDDirectory::class.java)) {
-                            // user comment field specifies encoding, unlike other string fields
-                            if (dir.containsTag(ExifSubIFDDirectory.TAG_USER_COMMENT)) {
-                                val string = dir.getDescription(ExifSubIFDDirectory.TAG_USER_COMMENT)
-                                if (string.isNotBlank()) {
-                                    description = string
-                                }
-                            }
-                        }
-                    }
-                    if (description == null) {
-                        for (dir in metadata.getDirectoriesOfType(ExifIFD0Directory::class.java)) {
-                            dir.getSafeString(ExifIFD0Directory.TAG_IMAGE_DESCRIPTION, acceptBlank = false) { description = it }
-                        }
-                    }
-                }
-            } catch (e: Exception) {
-                Log.w(LOG_TAG, "failed to read metadata by metadata-extractor for mimeType=$mimeType uri=$uri", e)
-            } catch (e: NoClassDefFoundError) {
-                Log.w(LOG_TAG, "failed to read metadata by metadata-extractor for mimeType=$mimeType uri=$uri", e)
-            } catch (e: AssertionError) {
-                Log.w(LOG_TAG, "failed to read metadata by metadata-extractor for mimeType=$mimeType uri=$uri", e)
-            }
-        }
-
-        result.success(description)
-    }
-
     companion object {
         private val LOG_TAG = LogUtils.createTag<MetadataFetchHandler>()
         const val CHANNEL = "deckers.thibault/aves/metadata_fetch"
@@ -1319,6 +1315,7 @@ class MetadataFetchHandler(private val context: Context) : MethodCallHandler {
 
         // overlay metadata
         private const val KEY_APERTURE = "aperture"
+        private const val KEY_DESCRIPTION = "description"
         private const val KEY_EXPOSURE_TIME = "exposureTime"
         private const val KEY_FOCAL_LENGTH = "focalLength"
         private const val KEY_ISO = "iso"

android/build.gradle

@@ -2,7 +2,7 @@ buildscript {
     ext {
         kotlin_version = '1.9.21'
         ksp_version = "$kotlin_version-1.0.15"
-        agp_version = '8.2.1'
+        agp_version = '8.2.2'
         glide_version = '4.16.0'
         // AppGallery Connect plugin versions: https://developer.huawei.com/consumer/en/doc/development/AppGallery-connect-Guides/agc-sdk-changenotes-0000001058732550
         huawei_agconnect_version = '1.9.1.300'

lib/convert/metadata/fields.dart

@@ -1,5 +1,9 @@
 import 'package:aves_model/aves_model.dart';
 
+extension ExtraMetadataSyntheticFieldConvert on MetadataSyntheticField {
+  String? get toPlatform => name;
+}
+
 extension ExtraMetadataFieldConvert on MetadataField {
   MetadataType get type {
     switch (this) {

lib/model/metadata/overlay.dart

@@ -4,18 +4,17 @@ import 'package:flutter/foundation.dart';
 @immutable
 class OverlayMetadata extends Equatable {
   final double? aperture, focalLength;
-  final String? exposureTime;
+  final String? description, exposureTime;
   final int? iso;
 
   @override
-  List<Object?> get props => [aperture, exposureTime, focalLength, iso];
+  List<Object?> get props => [aperture, description, exposureTime, focalLength, iso];
 
-  bool get isEmpty => aperture == null && exposureTime == null && focalLength == null && iso == null;
+  bool get hasShootingDetails => aperture != null || exposureTime != null || focalLength != null || iso != null;
-
-  bool get isNotEmpty => !isEmpty;
 
   const OverlayMetadata({
     this.aperture,
+    this.description,
     this.exposureTime,
     this.focalLength,
     this.iso,
@@ -24,6 +23,7 @@ class OverlayMetadata extends Equatable {
   factory OverlayMetadata.fromMap(Map map) {
     return OverlayMetadata(
       aperture: map['aperture'] as double?,
+      description: map['description'] as String?,
       exposureTime: map['exposureTime'] as String?,
       focalLength: map['focalLength'] as double?,
       iso: map['iso'] as int?,

lib/services/metadata/metadata_fetch_service.dart

@@ -22,7 +22,7 @@ abstract class MetadataFetchService {
 
   Future<CatalogMetadata?> getCatalogMetadata(AvesEntry entry, {bool background = false});
 
-  Future<OverlayMetadata?> getOverlayMetadata(AvesEntry entry);
+  Future<OverlayMetadata> getFields(AvesEntry entry, Set<MetadataSyntheticField> fields);
 
   Future<GeoTiffInfo?> getGeoTiffInfo(AvesEntry entry);
 
@@ -39,8 +39,6 @@ abstract class MetadataFetchService {
   Future<String?> getContentResolverProp(AvesEntry entry, String prop);
 
   Future<DateTime?> getDate(AvesEntry entry, MetadataField field);
-
-  Future<String?> getDescription(AvesEntry entry);
 }
 
 class PlatformMetadataFetchService implements MetadataFetchService {
@@ -112,15 +110,20 @@ class PlatformMetadataFetchService implements MetadataFetchService {
   }
 
   @override
-  Future<OverlayMetadata?> getOverlayMetadata(AvesEntry entry) async {
+  Future<OverlayMetadata> getFields(AvesEntry entry, Set<MetadataSyntheticField> fields) async {
-    if (entry.isSvg) return null;
+    if (fields.isNotEmpty && !entry.isSvg) {
-
       try {
-      // returns map with values for: 'aperture' (double), 'exposureTime' (description), 'focalLength' (double), 'iso' (int)
+        // returns fields on demand, with various value types:
-      final result = await _platform.invokeMethod('getOverlayMetadata', <String, dynamic>{
+        // 'aperture' (double),
+        // 'description' (string)
+        // 'exposureTime' (string),
+        // 'focalLength' (double),
+        // 'iso' (int),
+        final result = await _platform.invokeMethod('getFields', <String, dynamic>{
           'mimeType': entry.mimeType,
           'uri': entry.uri,
           'sizeBytes': entry.sizeBytes,
+          'fields': fields.map((v) => v.toPlatform).toList(),
         }) as Map;
         return OverlayMetadata.fromMap(result);
       } on PlatformException catch (e, stack) {
@@ -128,7 +131,8 @@ class PlatformMetadataFetchService implements MetadataFetchService {
           await reportService.recordError(e, stack);
         }
       }
-    return null;
+    }
+    return const OverlayMetadata();
   }
 
   @override
@@ -280,20 +284,4 @@ class PlatformMetadataFetchService implements MetadataFetchService {
     }
     return null;
   }
-
-  @override
-  Future<String?> getDescription(AvesEntry entry) async {
-    try {
-      return await _platform.invokeMethod('getDescription', <String, dynamic>{
-        'mimeType': entry.mimeType,
-        'uri': entry.uri,
-        'sizeBytes': entry.sizeBytes,
-      });
-    } on PlatformException catch (e, stack) {
-      if (entry.isValid) {
-        await reportService.recordError(e, stack);
-      }
-    }
-    return null;
-  }
 }

lib/widgets/common/action_mixins/entry_editor.dart

@@ -55,7 +55,8 @@ mixin EntryEditorMixin {
 
     final entry = entries.first;
     final initialTitle = entry.catalogMetadata?.xmpTitle ?? '';
-    final initialDescription = await metadataFetchService.getDescription(entry) ?? '';
+    final fields = await metadataFetchService.getFields(entry, {MetadataSyntheticField.description});
+    final initialDescription = fields.description ?? '';
 
     return showDialog<Map<DescriptionField, String?>>(
       context: context,

lib/widgets/viewer/overlay/details/details.dart

@@ -15,6 +15,7 @@ import 'package:aves/widgets/viewer/overlay/details/position_title.dart';
 import 'package:aves/widgets/viewer/overlay/details/rating_tags.dart';
 import 'package:aves/widgets/viewer/overlay/details/shooting.dart';
 import 'package:aves/widgets/viewer/page_entry_builder.dart';
+import 'package:aves_model/aves_model.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 import 'package:provider/provider.dart';
@@ -48,9 +49,9 @@ class _ViewerDetailOverlayState extends State<ViewerDetailOverlay> {
 
   AvesEntry? entryForIndex(int index) => index < entries.length ? entries[index] : null;
 
-  late Future<List<dynamic>?> _detailLoader;
+  late Future<OverlayMetadata> _detailLoader;
   AvesEntry? _lastEntry;
-  List<dynamic>? _lastDetails;
+  OverlayMetadata _lastDetails = const OverlayMetadata();
 
   @override
   void initState() {
@@ -70,12 +71,17 @@ class _ViewerDetailOverlayState extends State<ViewerDetailOverlay> {
   void _initDetailLoader() {
     final requestEntry = entry;
     if (requestEntry == null) {
-      _detailLoader = SynchronousFuture(null);
+      _detailLoader = SynchronousFuture(const OverlayMetadata());
     } else {
-      _detailLoader = Future.wait([
+      _detailLoader = metadataFetchService.getFields(requestEntry, {
-        settings.showOverlayShootingDetails ? metadataFetchService.getOverlayMetadata(requestEntry) : Future.value(null),
+        if (settings.showOverlayShootingDetails) ...{
-        settings.showOverlayDescription ? metadataFetchService.getDescription(requestEntry) : Future.value(null),
+          MetadataSyntheticField.aperture,
-      ]);
+          MetadataSyntheticField.exposureTime,
+          MetadataSyntheticField.focalLength,
+          MetadataSyntheticField.iso,
+        },
+        if (settings.showOverlayDescription) MetadataSyntheticField.description,
+      });
     }
   }
 
@@ -84,24 +90,20 @@ class _ViewerDetailOverlayState extends State<ViewerDetailOverlay> {
     return SafeArea(
       top: false,
       bottom: false,
-      child: FutureBuilder<List<dynamic>?>(
+      child: FutureBuilder<OverlayMetadata>(
         future: _detailLoader,
         builder: (context, snapshot) {
           if (snapshot.connectionState == ConnectionState.done && !snapshot.hasError) {
-            _lastDetails = snapshot.data;
+            _lastDetails = snapshot.data!;
             _lastEntry = entry;
           }
           if (_lastEntry == null) return const SizedBox();
           final mainEntry = _lastEntry!;
 
-          final shootingDetails = _lastDetails![0];
-          final description = _lastDetails![1];
-
           final multiPageController = widget.multiPageController;
           Widget _buildContent({AvesEntry? pageEntry}) => ViewerDetailOverlayContent(
                 pageEntry: pageEntry ?? mainEntry,
-                shootingDetails: shootingDetails,
+                details: _lastDetails,
-                description: description,
                 position: widget.hasCollection ? '${widget.index + 1}/${entries.length}' : null,
                 availableWidth: widget.availableSize.width,
                 multiPageController: multiPageController,
@@ -122,8 +124,7 @@ class _ViewerDetailOverlayState extends State<ViewerDetailOverlay> {
 
 class ViewerDetailOverlayContent extends StatelessWidget {
   final AvesEntry pageEntry;
-  final OverlayMetadata? shootingDetails;
+  final OverlayMetadata details;
-  final String? description;
   final String? position;
   final double availableWidth;
   final MultiPageController? multiPageController;
@@ -140,8 +141,7 @@ class ViewerDetailOverlayContent extends StatelessWidget {
   const ViewerDetailOverlayContent({
     super.key,
     required this.pageEntry,
-    required this.shootingDetails,
+    required this.details,
-    required this.description,
     required this.position,
     required this.availableWidth,
     required this.multiPageController,
@@ -244,27 +244,27 @@ class ViewerDetailOverlayContent extends StatelessWidget {
 
   Widget _buildDescriptionFullRow(BuildContext context) => _buildFullRowSwitcher(
         context: context,
-        visible: description != null,
+        visible: details.description != null,
         builder: (context) => OverlayRowExpander(
           expandedNotifier: expandedNotifier,
-          child: OverlayDescriptionRow(description: description!),
+          child: OverlayDescriptionRow(description: details.description!),
         ),
       );
 
   Widget _buildShootingFullRow(BuildContext context, double subRowWidth) => _buildFullRowSwitcher(
         context: context,
-        visible: shootingDetails != null && shootingDetails!.isNotEmpty,
+        visible: details.hasShootingDetails,
         builder: (context) => SizedBox(
           width: subRowWidth,
-          child: OverlayShootingRow(details: shootingDetails!),
+          child: OverlayShootingRow(details: details),
         ),
       );
 
   Widget _buildShootingSubRow(BuildContext context, double subRowWidth) => _buildSubRowSwitcher(
         context: context,
         subRowWidth: subRowWidth,
-        visible: shootingDetails != null && shootingDetails!.isNotEmpty,
+        visible: details.hasShootingDetails,
-        builder: (context) => OverlayShootingRow(details: shootingDetails!),
+        builder: (context) => OverlayShootingRow(details: details),
       );
 
   Widget _buildLocationFullRow(BuildContext context) => _buildFullRowSwitcher(

plugins/aves_model/lib/src/metadata/fields.dart

@@ -1,3 +1,11 @@
+enum MetadataSyntheticField {
+  aperture,
+  description,
+  exposureTime,
+  focalLength,
+  iso,
+}
+
 enum MetadataField {
   exifDate,
   exifDateOriginal,