Info: show metadata from SVG

lib/utils/constants.dart

@@ -293,6 +293,12 @@ class Constants {
       licenseUrl: 'https://github.com/flutter/plugins/blob/master/packages/url_launcher/url_launcher/LICENSE',
       sourceUrl: 'https://github.com/flutter/plugins/blob/master/packages/url_launcher/url_launcher',
     ),
+    Dependency(
+      name: 'XML',
+      license: 'MIT',
+      licenseUrl: 'https://github.com/renggli/dart-xml/blob/master/LICENSE',
+      sourceUrl: 'https://github.com/renggli/dart-xml',
+    ),
   ];
 }
 

lib/utils/string_utils.dart

@@ -0,0 +1,9 @@
+extension ExtraString on String {
+  static final _sentenceCaseStep1 = RegExp(r'([A-Z][a-z]|\[)');
+  static final _sentenceCaseStep2 = RegExp(r'([a-z])([A-Z])');
+
+  String toSentenceCase() {
+    var s = replaceFirstMapped(RegExp('.'), (m) => m.group(0).toUpperCase());
+    return s.replaceAllMapped(_sentenceCaseStep1, (m) => ' ${m.group(1)}').replaceAllMapped(_sentenceCaseStep2, (m) => '${m.group(1)} ${m.group(2)}').trim();
+  }
+}

lib/widgets/fullscreen/entry_action_delegate.dart

@@ -1,3 +1,5 @@
+import 'dart:convert';
+
 import 'package:aves/image_providers/uri_image_provider.dart';
 import 'package:aves/model/actions/entry_actions.dart';
 import 'package:aves/model/image_entry.dart';
@@ -202,7 +204,9 @@ class EntryActionDelegate with FeedbackMixin, PermissionAwareMixin {
       context,
       MaterialPageRoute(
         settings: RouteSettings(name: SourceViewerPage.routeName),
-        builder: (context) => SourceViewerPage(entry: entry),
+        builder: (context) => SourceViewerPage(
+          loader: () => ImageFileService.getImage(entry.uri, entry.mimeType, 0, false).then(utf8.decode),
+        ),
       ),
     );
   }

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

@@ -10,6 +10,7 @@ import 'package:aves/utils/constants.dart';
 import 'package:aves/widgets/common/identity/aves_expansion_tile.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/svg_tile.dart';
 import 'package:aves/widgets/fullscreen/info/metadata/xmp_tile.dart';
 import 'package:collection/collection.dart';
 import 'package:flutter/foundation.dart';
@@ -135,6 +136,7 @@ class _MetadataSectionSliverState extends State<MetadataSectionSliver> with Auto
         expandedNotifier: _expandedDirectoryNotifier,
       );
     }
+
     Widget thumbnail;
     final prefixChildren = <Widget>[];
     switch (dirName) {
@@ -168,7 +170,11 @@ class _MetadataSectionSliverState extends State<MetadataSectionSliver> with Auto
         if (thumbnail != null) thumbnail,
         Padding(
           padding: EdgeInsets.only(left: 8, right: 8, bottom: 8),
-          child: InfoRowGroup(dir.tags, maxValueLength: Constants.infoGroupMaxValueLength),
+          child: InfoRowGroup(
+            dir.tags,
+            maxValueLength: Constants.infoGroupMaxValueLength,
+            linkHandlers: dirName == SvgMetadata.directory ? SvgMetadata.getLinkHandlers(dir.tags) : null,
+          ),
         ),
       ],
     );
@@ -184,7 +190,7 @@ class _MetadataSectionSliverState extends State<MetadataSectionSliver> with Auto
     if (entry == null) return;
     if (_loadedMetadataUri.value == entry.uri) return;
     if (isVisible) {
-      final rawMetadata = await MetadataService.getAllMetadata(entry) ?? {};
+      final rawMetadata = await (entry.isSvg ? SvgMetadata.getAllMetadata(entry) : MetadataService.getAllMetadata(entry)) ?? {};
       final directories = rawMetadata.entries.map((dirKV) {
         var directoryName = dirKV.key as String ?? '';
 

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

@@ -0,0 +1,72 @@
+import 'dart:collection';
+import 'dart:convert';
+
+import 'package:aves/model/image_entry.dart';
+import 'package:aves/services/image_file_service.dart';
+import 'package:aves/utils/string_utils.dart';
+import 'package:aves/widgets/fullscreen/info/common.dart';
+import 'package:aves/widgets/fullscreen/source_viewer_page.dart';
+import 'package:flutter/cupertino.dart';
+import 'package:flutter/foundation.dart';
+import 'package:flutter/material.dart';
+import 'package:xml/xml.dart';
+
+class SvgMetadata {
+  static const directory = 'SVG';
+
+  static const _attributes = ['x', 'y', 'width', 'height', 'preserveAspectRatio', 'viewBox'];
+  static const _textElements = ['title', 'desc'];
+  static const _metadataElement = 'metadata';
+
+  static Future<Map<String, Map<String, String>>> getAllMetadata(ImageEntry entry) async {
+    try {
+      final result = <String, String>{};
+      final data = await ImageFileService.getImage(entry.uri, entry.mimeType, 0, false);
+
+      final document = XmlDocument.parse(utf8.decode(data));
+      final root = document.rootElement;
+
+      final metadata = root.getElement(_metadataElement);
+      result.addEntries([
+        ...root.attributes.where((a) => _attributes.contains(a.name.qualified)).map((a) => MapEntry(_formatKey(a.name.qualified), a.value)),
+        ..._textElements.map((name) => MapEntry(_formatKey(name), root.getElement(name)?.text)).where((kv) => kv.value != null),
+        if (metadata != null) MapEntry('Metadata', metadata.toXmlString(pretty: true)),
+      ]);
+
+      return {
+        directory: result,
+      };
+    } catch (exception, stack) {
+      debugPrint('failed to parse XML from SVG with exception=$exception\n$stack');
+      return null;
+    }
+  }
+
+  static Map<String, InfoLinkHandler> getLinkHandlers(SplayTreeMap<String, String> tags) {
+    return {
+      'Metadata': InfoLinkHandler(
+        linkText: 'View XML',
+        onTap: (context) {
+          Navigator.push(
+            context,
+            MaterialPageRoute(
+              settings: RouteSettings(name: SourceViewerPage.routeName),
+              builder: (context) => SourceViewerPage(
+                loader: () => SynchronousFuture(tags['Metadata']),
+              ),
+            ),
+          );
+        },
+      ),
+    };
+  }
+
+  static String _formatKey(String key) {
+    switch (key) {
+      case 'desc':
+        return 'Description';
+      default:
+        return key.toSentenceCase();
+    }
+  }
+}

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

@@ -1,6 +1,7 @@
 import 'package:aves/ref/brand_colors.dart';
 import 'package:aves/ref/xmp.dart';
 import 'package:aves/utils/constants.dart';
+import 'package:aves/utils/string_utils.dart';
 import 'package:aves/widgets/common/identity/highlight_title.dart';
 import 'package:aves/widgets/fullscreen/info/common.dart';
 import 'package:collection/collection.dart';
@@ -103,23 +104,14 @@ class XmpProp {
   final String path, value;
   final String displayKey;
 
-  static final sentenceCaseStep1 = RegExp(r'([A-Z][a-z]|\[)');
-  static final sentenceCaseStep2 = RegExp(r'([a-z])([A-Z])');
-
   XmpProp(this.path, this.value) : displayKey = formatKey(path);
 
   static String formatKey(String propPath) {
     return propPath.splitMapJoin(XMP.structFieldSeparator,
         onMatch: (match) => ' ${match.group(0)} ',
         onNonMatch: (s) {
-          // strip namespace
+          // strip namespace & format
-          var key = s.split(XMP.propNamespaceSeparator).last;
+          return s.split(XMP.propNamespaceSeparator).last.toSentenceCase();
-
-          // uppercase first letter
-          key = key.replaceFirstMapped(RegExp('.'), (m) => m.group(0).toUpperCase());
-
-          // sentence case
-          return key.replaceAllMapped(sentenceCaseStep1, (m) => ' ${m.group(1)}').replaceAllMapped(sentenceCaseStep2, (m) => '${m.group(1)} ${m.group(2)}').trim();
         });
   }
 

lib/widgets/fullscreen/source_viewer_page.dart

@@ -1,7 +1,3 @@
-import 'dart:convert';
-
-import 'package:aves/model/image_entry.dart';
-import 'package:aves/services/image_file_service.dart';
 import 'package:aves/widgets/common/aves_highlight.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_highlight/themes/darcula.dart';
@@ -9,10 +5,10 @@ import 'package:flutter_highlight/themes/darcula.dart';
 class SourceViewerPage extends StatefulWidget {
   static const routeName = '/fullscreen/source';
 
-  final ImageEntry entry;
+  final Future<String> Function() loader;
 
   const SourceViewerPage({
-    @required this.entry,
+    @required this.loader,
   });
 
   @override
@@ -22,12 +18,10 @@ class SourceViewerPage extends StatefulWidget {
 class _SourceViewerPageState extends State<SourceViewerPage> {
   Future<String> _loader;
 
-  ImageEntry get entry => widget.entry;
-
   @override
   void initState() {
     super.initState();
-    _loader = ImageFileService.getImage(entry.uri, entry.mimeType, 0, false).then(utf8.decode);
+    _loader = widget.loader();
   }
 
   @override
@@ -40,12 +34,8 @@ class _SourceViewerPageState extends State<SourceViewerPage> {
         child: FutureBuilder<String>(
           future: _loader,
           builder: (context, snapshot) {
-            if (snapshot.hasError) {
+            if (snapshot.hasError) return Text(snapshot.error.toString());
-              return Text(snapshot.error.toString());
+            if (!snapshot.hasData) return SizedBox.shrink();
-            }
-            if (snapshot.connectionState != ConnectionState.done) {
-              return SizedBox.shrink();
-            }
 
             final source = snapshot.data;
             final highlightView = AvesHighlightView(

pubspec.lock

@@ -1146,7 +1146,7 @@ packages:
     source: hosted
     version: "0.1.2"
   xml:
-    dependency: transitive
+    dependency: "direct main"
     description:
       name: xml
       url: "https://pub.dartlang.org"

pubspec.yaml

@@ -11,7 +11,7 @@ version: 1.2.8+34
 
 # dnfield/flutter_svg (as of v0.19.1):
 # - `Could not parse "currentColor" as a color`: https://github.com/dnfield/flutter_svg/issues/31
-# - no <style> support: https://github.com/dnfield/flutter_svg/issues/105
+# - `The <style> element is not implemented in this library.`: https://github.com/dnfield/flutter_svg/issues/105
 # - inconsistent % unit support: https://github.com/dnfield/flutter_svg/issues/110
 
 # video_player (as of v0.10.8+2, backed by ExoPlayer):
@@ -87,6 +87,7 @@ dependencies:
   streams_channel:
   tuple:
   url_launcher:
+  xml:
 
 dev_dependencies:
   flutter_test:

test/utils/string_utils_test.dart

@@ -0,0 +1,17 @@
+import 'package:test/test.dart';
+import 'package:aves/utils/string_utils.dart';
+
+void main() {
+  test('Sentence case', () {
+    expect('XResolution'.toSentenceCase(), 'X Resolution');
+    expect('PixelXDimension'.toSentenceCase(), 'Pixel X Dimension');
+    expect('FocalPointX'.toSentenceCase(), 'Focal Point X');
+
+    expect('ISOSpeedRatings[1]'.toSentenceCase(), 'ISO Speed Ratings [1]');
+    expect('LegacyIPTCDigest'.toSentenceCase(), 'Legacy IPTC Digest');
+    expect('DocumentID'.toSentenceCase(), 'Document ID');
+
+    expect('H'.toSentenceCase(), 'H');
+    expect('LW[1]'.toSentenceCase(), 'LW [1]');
+  });
+}