From 9c08e5a635f8855b9d034ba1d72914ab69d95462 Mon Sep 17 00:00:00 2001
From: Ming Ming <nkming2@gmail.com>
Date: Sun, 20 Jun 2021 19:40:28 +0800
Subject: [PATCH] Simplify File datetime access

---
 lib/entity/file.dart               | 10 +++++++---
 lib/widget/home_albums.dart        |  4 +---
 lib/widget/home_photos.dart        |  2 +-
 lib/widget/viewer_detail_pane.dart |  8 +-------
 4 files changed, 10 insertions(+), 14 deletions(-)

diff --git a/lib/entity/file.dart b/lib/entity/file.dart
index d30bcd0a..e35a020e 100644
--- a/lib/entity/file.dart
+++ b/lib/entity/file.dart
@@ -9,9 +9,7 @@ import 'package:nc_photos/or_null.dart';
 import 'package:nc_photos/string_extension.dart';
 
 int compareFileDateTimeDescending(File x, File y) {
-  final xDate = x.metadata?.exif?.dateTimeOriginal ?? x.lastModified;
-  final yDate = y.metadata?.exif?.dateTimeOriginal ?? y.lastModified;
-  final tmp = yDate.compareTo(xDate);
+  final tmp = y.bestDateTime.compareTo(x.bestDateTime);
   if (tmp != 0) {
     return tmp;
   } else {
@@ -394,6 +392,12 @@ class File with EquatableMixin {
   final bool isArchived;
 }
 
+extension FileExtension on File {
+  DateTime get bestDateTime {
+    return metadata?.exif?.dateTimeOriginal ?? lastModified;
+  }
+}
+
 class FileRepo {
   FileRepo(this.dataSrc);
 
diff --git a/lib/widget/home_albums.dart b/lib/widget/home_albums.dart
index df2d2efc..11c48d00 100644
--- a/lib/widget/home_albums.dart
+++ b/lib/widget/home_albums.dart
@@ -392,9 +392,7 @@ class _HomeAlbumsState extends State<HomeAlbums> {
             .where((element) => file_util.isSupportedFormat(element))
             .sorted(compareFileDateTimeDescending)
             .first;
-        return Tuple2(
-            lastItem.metadata?.exif?.dateTimeOriginal ?? lastItem.lastModified,
-            e);
+        return Tuple2(lastItem.bestDateTime, e);
       } catch (_) {
         return Tuple2(e.lastUpdated, e);
       }
diff --git a/lib/widget/home_photos.dart b/lib/widget/home_photos.dart
index 44dd82a3..cbd5adea 100644
--- a/lib/widget/home_photos.dart
+++ b/lib/widget/home_photos.dart
@@ -455,7 +455,7 @@ class _HomePhotosState extends State<HomePhotos>
         final f = _backingFiles[i];
 
         String newDateStr;
-        final date = f.metadata?.exif?.dateTimeOriginal ?? f.lastModified;
+        final date = f.bestDateTime;
         if (date == null) {
           newDateStr = "";
         } else if (_thumbZoomLevel >= 0) {
diff --git a/lib/widget/viewer_detail_pane.dart b/lib/widget/viewer_detail_pane.dart
index 24a6d4af..555843f7 100644
--- a/lib/widget/viewer_detail_pane.dart
+++ b/lib/widget/viewer_detail_pane.dart
@@ -59,7 +59,7 @@ class _ViewerDetailPaneState extends State<ViewerDetailPane> {
 
   @override
   build(BuildContext context) {
-    final dateTime = (_dateTime ?? widget.file.lastModified).toLocal();
+    final dateTime = widget.file.bestDateTime.toLocal();
     final dateStr = DateFormat(DateFormat.YEAR_ABBR_MONTH_DAY).format(dateTime);
     final timeStr = DateFormat(DateFormat.HOUR_MINUTE).format(dateTime);
 
@@ -265,11 +265,6 @@ class _ViewerDetailPaneState extends State<ViewerDetailPane> {
 
   void _updateMetadataExif(Exif exif) {
     _log.info("[_updateMetadataExif] $exif");
-    if (exif.dateTimeOriginal != null) {
-      setState(() {
-        _dateTime = exif.dateTimeOriginal;
-      });
-    }
     if (exif.make != null && exif.model != null) {
       setState(() {
         _model = "${exif.make} ${exif.model}";
@@ -362,7 +357,6 @@ class _ViewerDetailPaneState extends State<ViewerDetailPane> {
   int _width;
   int _height;
   // EXIF data
-  DateTime _dateTime;
   String _model;
   double _fNumber;
   String _exposureTime;