Revert "Remove setup page for EXIF"

This reverts commit 7ea37dc491.

app/lib/widget/setup.dart

@@ -43,6 +43,7 @@ class _SetupState extends State<Setup> {
   Widget _buildContent(BuildContext context) {
     final page = _pageController.hasClients ? _pageController.page!.round() : 0;
     final pages = <Widget>[
+      if (_initialProgress & _PageId.exif == 0) _Exif(),
       if (_initialProgress & _PageId.hiddenPrefDirNotice == 0)
         _HiddenPrefDirNotice(),
     ];
@@ -124,14 +125,73 @@ class _SetupState extends State<Setup> {
 }
 
 class _PageId {
+  static const exif = 0x01;
   static const hiddenPrefDirNotice = 0x02;
-  static const all = hiddenPrefDirNotice;
+  static const all = exif | hiddenPrefDirNotice;
 }
 
 abstract class _Page {
   int getPageId();
 }
 
+class _Exif extends StatefulWidget implements _Page {
+  @override
+  createState() => _ExifState();
+
+  @override
+  getPageId() => _PageId.exif;
+}
+
+class _ExifState extends State<_Exif> {
+  @override
+  build(BuildContext context) {
+    return SingleChildScrollView(
+      child: Column(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          SwitchListTile(
+            title: Text(L10n.global().settingsExifSupportTitle),
+            value: _isEnableExif,
+            onChanged: _onValueChanged,
+          ),
+          const SizedBox(height: 8),
+          Padding(
+            padding: const EdgeInsets.symmetric(horizontal: 16),
+            child: Text(L10n.global().exifSupportDetails),
+          ),
+          const SizedBox(height: 16),
+          Padding(
+            padding: const EdgeInsets.symmetric(horizontal: 16),
+            child: Text(
+              L10n.global().setupSettingsModifyLaterHint,
+              style: Theme.of(context)
+                  .textTheme
+                  .bodyMedium
+                  ?.copyWith(fontStyle: FontStyle.italic),
+            ),
+          ),
+          const SizedBox(height: 8),
+        ],
+      ),
+    );
+  }
+
+  @override
+  dispose() {
+    super.dispose();
+    // persist user's choice
+    Pref().setEnableExif(_isEnableExif);
+  }
+
+  void _onValueChanged(bool value) {
+    setState(() {
+      _isEnableExif = value;
+    });
+  }
+
+  bool _isEnableExif = Pref().isEnableExifOr();
+}
+
 class _HiddenPrefDirNotice extends StatefulWidget implements _Page {
   @override
   createState() => _HiddenPrefDirNoticeState();