refactor: unify mail display with shared ThreadTile widget

Replace EmailTile (used only in search results) and the duplicated inline
ListTile blocks in EmailListScreen and CombinedInboxScreen with a single
ThreadTile widget. Add EmailThread.fromEmail factory so search results
(which come back as individual Email objects) can be displayed via the
same widget. Delete email_tile.dart.

Closes #429

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

lib/core/models/email.dart

@@ -192,6 +192,22 @@ class EmailThread {
     required this.accountId,
     required this.mailboxPath,
   });
+
+  /// Wraps a single [Email] as a one-message thread for uniform rendering.
+  factory EmailThread.fromEmail(Email e) => EmailThread(
+        threadId: e.threadId ?? e.id,
+        subject: e.subject,
+        participants: e.from,
+        latestDate: e.sentAt ?? e.receivedAt,
+        messageCount: 1,
+        hasUnread: !e.isSeen,
+        isFlagged: e.isFlagged,
+        latestEmailId: e.id,
+        preview: e.preview,
+        emailIds: [e.id],
+        accountId: e.accountId,
+        mailboxPath: e.mailboxPath,
+      );
 }
 
 class EmailAddress {

lib/ui/screens/combined_inbox_screen.dart

@@ -3,20 +3,13 @@ import 'dart:async';
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:go_router/go_router.dart';
-import 'package:intl/intl.dart';
 
 import 'package:sharedinbox/core/models/account.dart';
 import 'package:sharedinbox/core/models/email.dart';
 import 'package:sharedinbox/core/models/undo_action.dart';
 import 'package:sharedinbox/di.dart';
+import 'package:sharedinbox/ui/widgets/thread_tile.dart';
 
-final _dateFmt = DateFormat('MMM d');
-final _formattedDates = <int, String>{};
-
-int _dayKey(DateTime dt) => dt.year * 10000 + dt.month * 100 + dt.day;
-
-String _fmtDate(DateTime dt) =>
-    _formattedDates[_dayKey(dt)] ??= _dateFmt.format(dt);
 
 class CombinedInboxScreen extends ConsumerStatefulWidget {
   const CombinedInboxScreen({super.key});
@@ -218,76 +211,10 @@ class _CombinedInboxScreenState extends ConsumerState<CombinedInboxScreen> {
     Map<String, String> accountNames,
     bool showAccount,
   ) {
-    final senderNames =
-        t.participants.map((a) => a.name ?? a.email).take(3).join(', ');
-
-    final tile = ListTile(
-      leading: Icon(
-        t.hasUnread ? Icons.mail : Icons.mail_outline,
-        color: t.hasUnread ? Theme.of(ctx).colorScheme.primary : null,
-      ),
-      title: Row(
-        children: [
-          Expanded(
-            child: Text(
-              senderNames.isEmpty ? '(unknown)' : senderNames,
-              style: t.hasUnread
-                  ? const TextStyle(fontWeight: FontWeight.bold)
-                  : null,
-              overflow: TextOverflow.ellipsis,
-            ),
-          ),
-          if (t.messageCount > 1)
-            Padding(
-              padding: const EdgeInsets.only(left: 4),
-              child: Text(
-                '[${t.messageCount}]',
-                style: Theme.of(ctx).textTheme.bodySmall,
-              ),
-            ),
-        ],
-      ),
-      subtitle: Column(
-        crossAxisAlignment: CrossAxisAlignment.start,
-        children: [
-          Text(
-            t.subject ?? '(no subject)',
-            maxLines: 1,
-            overflow: TextOverflow.ellipsis,
-            style: t.hasUnread
-                ? const TextStyle(fontWeight: FontWeight.bold)
-                : null,
-          ),
-          if (t.preview != null && t.preview!.isNotEmpty)
-            Text(
-              t.preview!,
-              maxLines: 1,
-              overflow: TextOverflow.ellipsis,
-              style: Theme.of(ctx).textTheme.bodySmall,
-            ),
-          if (showAccount)
-            Text(
-              accountNames[t.accountId] ?? t.accountId,
-              maxLines: 1,
-              overflow: TextOverflow.ellipsis,
-              style: Theme.of(ctx).textTheme.bodySmall?.copyWith(
-                    color: Theme.of(ctx).colorScheme.primary,
-                  ),
-            ),
-        ],
-      ),
-      trailing: Row(
-        mainAxisSize: MainAxisSize.min,
-        children: [
-          if (t.isFlagged)
-            const Icon(Icons.star, color: Colors.amber, size: 16),
-          const SizedBox(width: 4),
-          Text(
-            _fmtDate(t.latestDate),
-            style: Theme.of(ctx).textTheme.bodySmall,
-          ),
-        ],
-      ),
+    final tile = ThreadTile(
+      thread: t,
+      locationLabel:
+          showAccount ? (accountNames[t.accountId] ?? t.accountId) : null,
       onTap: t.messageCount > 1
           ? () => context.push(
                 '/accounts/${t.accountId}/mailboxes'

lib/ui/screens/email_list_screen.dart

@@ -12,19 +12,10 @@ import 'package:sharedinbox/core/models/user_preferences.dart';
 import 'package:sharedinbox/core/repositories/email_repository.dart';
 import 'package:sharedinbox/di.dart';
 import 'package:sharedinbox/ui/screens/email_action_helpers.dart';
-import 'package:sharedinbox/ui/widgets/email_tile.dart';
 import 'package:sharedinbox/ui/widgets/folder_drawer.dart';
 import 'package:sharedinbox/ui/widgets/snooze_picker.dart';
+import 'package:sharedinbox/ui/widgets/thread_tile.dart';
 
-final _dateFmt = DateFormat('MMM d');
-// Cache formatted dates by local calendar day so DateFormat.format is called
-// at most once per unique date rather than once per list item per rebuild.
-final _formattedDates = <int, String>{};
-
-int _dayKey(DateTime dt) => dt.year * 10000 + dt.month * 100 + dt.day;
-
-String _fmtDate(DateTime dt) =>
-    _formattedDates[_dayKey(dt)] ??= _dateFmt.format(dt);
 
 class EmailListScreen extends ConsumerStatefulWidget {
   const EmailListScreen({
@@ -689,10 +680,10 @@ class _EmailListScreenState extends ConsumerState<EmailListScreen> {
         }
         final t = threads[i];
         final isSelected = _selectedThreadIds.contains(t.threadId);
-        final senderNames =
-            t.participants.map((a) => a.name ?? a.email).take(3).join(', ');
 
-        final tile = ListTile(
+        final tile = ThreadTile(
+          thread: t,
+          selected: isSelected,
           leading: SizedBox(
             width: 40,
             child: _selecting
@@ -700,65 +691,7 @@ class _EmailListScreenState extends ConsumerState<EmailListScreen> {
                     value: isSelected,
                     onChanged: (_) => _toggleThreadSelection(t),
                   )
-                : Icon(
-                    t.hasUnread ? Icons.mail : Icons.mail_outline,
-                    color:
-                        t.hasUnread ? Theme.of(ctx).colorScheme.primary : null,
-                  ),
-          ),
-          title: Row(
-            children: [
-              Expanded(
-                child: Text(
-                  senderNames.isEmpty ? '(unknown)' : senderNames,
-                  style: t.hasUnread
-                      ? const TextStyle(fontWeight: FontWeight.bold)
-                      : null,
-                  overflow: TextOverflow.ellipsis,
-                ),
-              ),
-              if (t.messageCount > 1)
-                Padding(
-                  padding: const EdgeInsets.only(left: 4),
-                  child: Text(
-                    '[${t.messageCount}]',
-                    style: Theme.of(ctx).textTheme.bodySmall,
-                  ),
-                ),
-            ],
-          ),
-          subtitle: Column(
-            crossAxisAlignment: CrossAxisAlignment.start,
-            children: [
-              Text(
-                t.subject ?? '(no subject)',
-                maxLines: 1,
-                overflow: TextOverflow.ellipsis,
-                style: t.hasUnread
-                    ? const TextStyle(fontWeight: FontWeight.bold)
-                    : null,
-              ),
-              if (t.preview != null && t.preview!.isNotEmpty)
-                Text(
-                  t.preview!,
-                  maxLines: 1,
-                  overflow: TextOverflow.ellipsis,
-                  style: Theme.of(ctx).textTheme.bodySmall,
-                ),
-            ],
-          ),
-          selected: isSelected,
-          trailing: Row(
-            mainAxisSize: MainAxisSize.min,
-            children: [
-              if (t.isFlagged)
-                const Icon(Icons.star, color: Colors.amber, size: 16),
-              const SizedBox(width: 4),
-              Text(
-                _fmtDate(t.latestDate),
-                style: Theme.of(ctx).textTheme.bodySmall,
-              ),
-            ],
+                : null,
           ),
           onTap: _selecting
               ? () => _toggleThreadSelection(t)
@@ -856,9 +789,10 @@ class _EmailListScreenState extends ConsumerState<EmailListScreen> {
       itemCount: emails.length,
       itemBuilder: (ctx, i) {
         final e = emails[i];
+        final t = EmailThread.fromEmail(e);
         final isSelected = _selectedSearchIds.contains(e.id);
-        return EmailTile(
-          email: e,
+        return ThreadTile(
+          thread: t,
           selected: isSelected,
           leading: SizedBox(
             width: 40,

lib/ui/screens/search_screen.dart

@@ -8,7 +8,7 @@ import 'package:sharedinbox/core/models/email.dart';
 import 'package:sharedinbox/core/models/mailbox.dart';
 import 'package:sharedinbox/core/utils/logger.dart';
 import 'package:sharedinbox/di.dart';
-import 'package:sharedinbox/ui/widgets/email_tile.dart';
+import 'package:sharedinbox/ui/widgets/thread_tile.dart';
 
 final _searchHistoryProvider = FutureProvider.autoDispose<List<String>>((
   ref,
@@ -189,9 +189,9 @@ class _SearchScreenState extends ConsumerState<SearchScreen> {
         if (r.emails.isNotEmpty) ...[
           const _SectionHeader('Messages'),
           for (final e in r.emails)
-            EmailTile(
-              email: e,
-              showLocation: true,
+            ThreadTile(
+              thread: EmailThread.fromEmail(e),
+              locationLabel: '${e.accountId} • ${e.mailboxPath}',
               onTap: () => context.push(
                 '/accounts/${e.accountId}/mailboxes'
                 '/${Uri.encodeComponent(e.mailboxPath)}'

lib/ui/widgets/email_tile.dart

@@ -1,74 +0,0 @@
-import 'package:flutter/material.dart';
-import 'package:intl/intl.dart';
-
-import 'package:sharedinbox/core/models/email.dart';
-
-final _dateFmt = DateFormat('MMM d');
-
-/// A flat list tile for an individual [email].
-///
-/// Used in search-result lists and the per-mailbox search overlay.
-/// Pass a custom [leading] widget to support selection-mode checkboxes.
-class EmailTile extends StatelessWidget {
-  const EmailTile({
-    super.key,
-    required this.email,
-    required this.onTap,
-    this.leading,
-    this.selected = false,
-    this.onLongPress,
-    this.showLocation = false,
-  });
-
-  final Email email;
-  final VoidCallback onTap;
-  final Widget? leading;
-  final bool selected;
-  final VoidCallback? onLongPress;
-
-  /// When true, appends `accountId • mailboxPath` as a second subtitle line.
-  final bool showLocation;
-
-  @override
-  Widget build(BuildContext context) {
-    final sender = email.from.isNotEmpty
-        ? (email.from.first.name ?? email.from.first.email)
-        : '(unknown)';
-    final date = email.sentAt != null ? _dateFmt.format(email.sentAt!) : '';
-
-    return ListTile(
-      leading: leading ??
-          Icon(
-            email.isSeen ? Icons.mail_outline : Icons.mail,
-            color: email.isSeen ? null : Theme.of(context).colorScheme.primary,
-          ),
-      title: Text(
-        sender,
-        style:
-            email.isSeen ? null : const TextStyle(fontWeight: FontWeight.bold),
-        overflow: TextOverflow.ellipsis,
-      ),
-      subtitle: Column(
-        crossAxisAlignment: CrossAxisAlignment.start,
-        children: [
-          Text(
-            email.subject ?? '(no subject)',
-            maxLines: 1,
-            overflow: TextOverflow.ellipsis,
-          ),
-          if (showLocation)
-            Text(
-              '${email.accountId} • ${email.mailboxPath}',
-              style: Theme.of(context).textTheme.bodySmall,
-            ),
-        ],
-      ),
-      trailing: date.isEmpty
-          ? null
-          : Text(date, style: Theme.of(context).textTheme.bodySmall),
-      selected: selected,
-      onTap: onTap,
-      onLongPress: onLongPress,
-    );
-  }
-}

lib/ui/widgets/thread_tile.dart

@@ -0,0 +1,121 @@
+import 'package:flutter/material.dart';
+import 'package:intl/intl.dart';
+
+import 'package:sharedinbox/core/models/email.dart';
+
+final _dateFmt = DateFormat('MMM d');
+// Cache formatted dates by local calendar day to avoid repeated DateFormat.format calls.
+final _formattedDates = <int, String>{};
+
+int _dayKey(DateTime dt) => dt.year * 10000 + dt.month * 100 + dt.day;
+
+String _fmtDate(DateTime dt) =>
+    _formattedDates[_dayKey(dt)] ??= _dateFmt.format(dt);
+
+/// A list tile for an [EmailThread].
+///
+/// Used in inbox lists, combined inbox, and search result lists.
+/// Pass a custom [leading] widget to support selection-mode checkboxes.
+/// Pass [locationLabel] to show an extra subtitle line (e.g. account name or
+/// "accountId • mailboxPath") — useful in cross-mailbox views.
+class ThreadTile extends StatelessWidget {
+  const ThreadTile({
+    super.key,
+    required this.thread,
+    required this.onTap,
+    this.leading,
+    this.selected = false,
+    this.onLongPress,
+    this.locationLabel,
+  });
+
+  final EmailThread thread;
+  final VoidCallback onTap;
+  final Widget? leading;
+  final bool selected;
+  final VoidCallback? onLongPress;
+
+  /// When non-null, appended as an extra subtitle line in primary colour.
+  final String? locationLabel;
+
+  @override
+  Widget build(BuildContext context) {
+    final senderNames = thread.participants.isEmpty
+        ? '(unknown)'
+        : thread.participants.map((a) => a.name ?? a.email).take(3).join(', ');
+
+    return ListTile(
+      leading: leading ??
+          Icon(
+            thread.hasUnread ? Icons.mail : Icons.mail_outline,
+            color:
+                thread.hasUnread ? Theme.of(context).colorScheme.primary : null,
+          ),
+      title: Row(
+        children: [
+          Expanded(
+            child: Text(
+              senderNames,
+              style: thread.hasUnread
+                  ? const TextStyle(fontWeight: FontWeight.bold)
+                  : null,
+              overflow: TextOverflow.ellipsis,
+            ),
+          ),
+          if (thread.messageCount > 1)
+            Padding(
+              padding: const EdgeInsets.only(left: 4),
+              child: Text(
+                '[${thread.messageCount}]',
+                style: Theme.of(context).textTheme.bodySmall,
+              ),
+            ),
+        ],
+      ),
+      subtitle: Column(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          Text(
+            thread.subject ?? '(no subject)',
+            maxLines: 1,
+            overflow: TextOverflow.ellipsis,
+            style: thread.hasUnread
+                ? const TextStyle(fontWeight: FontWeight.bold)
+                : null,
+          ),
+          if (thread.preview != null && thread.preview!.isNotEmpty)
+            Text(
+              thread.preview!,
+              maxLines: 1,
+              overflow: TextOverflow.ellipsis,
+              style: Theme.of(context).textTheme.bodySmall,
+            ),
+          if (locationLabel != null)
+            Text(
+              locationLabel!,
+              maxLines: 1,
+              overflow: TextOverflow.ellipsis,
+              style: Theme.of(context).textTheme.bodySmall?.copyWith(
+                    color: Theme.of(context).colorScheme.primary,
+                  ),
+            ),
+        ],
+      ),
+      trailing: Row(
+        mainAxisSize: MainAxisSize.min,
+        children: [
+          if (thread.isFlagged)
+            const Icon(Icons.star, color: Colors.amber, size: 16),
+          const SizedBox(width: 4),
+          Text(
+            _fmtDate(thread.latestDate),
+            style: Theme.of(context).textTheme.bodySmall,
+          ),
+        ],
+      ),
+      selected: selected,
+      onTap: onTap,
+      onLongPress: onLongPress,
+    );
+  }
+}

pubspec.lock

@@ -659,10 +659,10 @@ packages:
     dependency: transitive
     description:
       name: meta
-      sha256: "1741988757a65eb6b36abe716829688cf01910bbf91c34354ff7ec1c3de2b349"
+      sha256: "23f08335362185a5ea2ad3a4e597f1375e78bce8a040df5c600c8d3552ef2394"
       url: "https://pub.dev"
     source: hosted
-    version: "1.18.0"
+    version: "1.17.0"
   mime:
     dependency: "direct main"
     description:
@@ -1088,26 +1088,26 @@ packages:
     dependency: "direct dev"
     description:
       name: test
-      sha256: "8d9ceddbab833f180fbefed08afa76d7c03513dfdba87ffcec2718b02bbcbf20"
+      sha256: "280d6d890011ca966ad08df7e8a4ddfab0fb3aa49f96ed6de56e3521347a9ae7"
       url: "https://pub.dev"
     source: hosted
-    version: "1.31.0"
+    version: "1.30.0"
   test_api:
     dependency: transitive
     description:
       name: test_api
-      sha256: "949a932224383300f01be9221c39180316445ecb8e7547f70a41a35bf421fb9e"
+      sha256: "8161c84903fd860b26bfdefb7963b3f0b68fee7adea0f59ef805ecca346f0c7a"
       url: "https://pub.dev"
     source: hosted
-    version: "0.7.11"
+    version: "0.7.10"
   test_core:
     dependency: transitive
     description:
       name: test_core
-      sha256: "1991d4cfe85d5043241acac92962c3977c8d2f2add1ee73130c7b286417d1d34"
+      sha256: "0381bd1585d1a924763c308100f2138205252fb90c9d4eeaf28489ee65ccde51"
       url: "https://pub.dev"
     source: hosted
-    version: "0.6.17"
+    version: "0.6.16"
   timezone:
     dependency: transitive
     description: