feat: Implement polls

lib/pages/chat/start_poll_bottom_sheet.dart

@@ -0,0 +1,171 @@
+import 'package:flutter/material.dart';
+
+import 'package:matrix/matrix.dart';
+
+import 'package:fluffychat/l10n/l10n.dart';
+import 'package:fluffychat/utils/localized_exception_extension.dart';
+
+class StartPollBottomSheet extends StatefulWidget {
+  final Room room;
+  const StartPollBottomSheet({required this.room, super.key});
+
+  @override
+  State<StartPollBottomSheet> createState() => _StartPollBottomSheetState();
+}
+
+class _StartPollBottomSheetState extends State<StartPollBottomSheet> {
+  final TextEditingController _bodyController = TextEditingController();
+  bool _allowMultipleAnswers = false;
+  final List<TextEditingController> _answers = [
+    TextEditingController(),
+    TextEditingController(),
+  ];
+  PollKind _pollKind = PollKind.disclosed;
+
+  bool _canCreate = false;
+
+  bool isLoading = false;
+
+  String? _txid;
+
+  void _createPoll() async {
+    try {
+      var id = 0;
+      _txid ??= widget.room.client.generateUniqueTransactionId();
+      await widget.room.startPoll(
+        question: _bodyController.text.trim(),
+        answers: _answers
+            .map(
+              (answerController) => PollAnswer(
+                id: (++id).toString(),
+                mText: answerController.text.trim(),
+              ),
+            )
+            .toList(),
+        kind: _pollKind,
+        maxSelections: _allowMultipleAnswers ? _answers.length : 1,
+        txid: _txid,
+      );
+      Navigator.of(context).pop();
+    } catch (e, s) {
+      Logs().w('Unable to create poll', e, s);
+      if (!mounted) return;
+      ScaffoldMessenger.of(context).showSnackBar(
+        SnackBar(content: Text(e.toLocalizedString(context))),
+      );
+    }
+  }
+
+  void _updateCanCreate([_]) {
+    final newCanCreate = _bodyController.text.trim().isNotEmpty &&
+        !_answers.any((controller) => controller.text.trim().isEmpty);
+    if (_canCreate != newCanCreate) {
+      setState(() {
+        _canCreate = newCanCreate;
+      });
+    }
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    const maxAnswers = 10;
+    return Scaffold(
+      appBar: AppBar(
+        leading: CloseButton(
+          onPressed: Navigator.of(context).pop,
+        ),
+        title: Text(L10n.of(context).startPoll),
+      ),
+      body: ListView(
+        padding: const EdgeInsets.symmetric(horizontal: 32, vertical: 16),
+        children: [
+          SegmentedButton<PollKind>(
+            selected: {_pollKind},
+            multiSelectionEnabled: false,
+            onSelectionChanged: (pollKind) => setState(() {
+              _pollKind = pollKind.first;
+            }),
+            segments: [
+              ButtonSegment(
+                value: PollKind.disclosed,
+                label: Text(
+                  L10n.of(context).answersVisible,
+                ),
+              ),
+              ButtonSegment(
+                value: PollKind.undisclosed,
+                label: Text(
+                  L10n.of(context).answersHidden,
+                ),
+              ),
+            ],
+          ),
+          const SizedBox(height: 32),
+          TextField(
+            controller: _bodyController,
+            minLines: 1,
+            maxLines: 4,
+            maxLength: 512,
+            onChanged: _updateCanCreate,
+            decoration: InputDecoration(
+              hintText: L10n.of(context).pollQuestion,
+              counter: const SizedBox.shrink(),
+            ),
+          ),
+          const Divider(height: 32),
+          ..._answers.map(
+            (answerController) => Padding(
+              padding: const EdgeInsets.only(bottom: 16.0),
+              child: TextField(
+                controller: answerController,
+                onChanged: _updateCanCreate,
+                maxLength: 64,
+                decoration: InputDecoration(
+                  counter: const SizedBox.shrink(),
+                  hintText: L10n.of(context).answerOption,
+                  suffixIcon: _answers.length == 2
+                      ? null
+                      : IconButton(
+                          icon: const Icon(Icons.cancel_outlined),
+                          onPressed: () => setState(() {
+                            _answers.remove(answerController..dispose());
+                          }),
+                        ),
+                ),
+              ),
+            ),
+          ),
+          Align(
+            alignment: Alignment.centerLeft,
+            child: TextButton.icon(
+              icon: const Icon(Icons.add_outlined),
+              onPressed: _answers.length < maxAnswers
+                  ? () => setState(() {
+                        _answers.add(TextEditingController());
+                      })
+                  : null,
+              label: Text(L10n.of(context).addAnswerOption),
+            ),
+          ),
+          ListTile(
+            contentPadding: EdgeInsets.zero,
+            leading: Switch.adaptive(
+              value: _allowMultipleAnswers,
+              onChanged: (allow) => setState(() {
+                _allowMultipleAnswers = allow;
+              }),
+            ),
+            title: Text(L10n.of(context).allowMultipleAnswers),
+          ),
+          const SizedBox(height: 8),
+          ElevatedButton(
+            onPressed: !isLoading && _canCreate ? _createPoll : null,
+            child: isLoading
+                ? const LinearProgressIndicator()
+                : Text(L10n.of(context).startPoll),
+          ),
+        ],
+      ),
+    );
+  }
+}