refactor(ui): improve message input controller

2021-12-01 10:52:45 +01:00
parent 04f9208273
commit 0b0ff753d4
14 changed files with 241 additions and 241 deletions
@@ -58,7 +58,7 @@ class Message extends Equatable {
    this.ownReactions,
    this.parentId,
    this.quotedMessage,
-    this.quotedMessageId,
+    String? quotedMessageId,
    this.replyCount = 0,
    this.threadParticipants,
    this.showInChannel,
@@ -72,16 +72,19 @@ class Message extends Equatable {
    this.pinnedBy,
    this.extraData = const {},
    this.deletedAt,
-    this.status = MessageSendingStatus.sent,
+    this.status = MessageSendingStatus.sending,
    this.i18n,
  })  : id = id ?? const Uuid().v4(),
        pinExpires = pinExpires?.toUtc(),
-        createdAt = createdAt ?? DateTime.now(),
-        updatedAt = updatedAt ?? DateTime.now();
+        _createdAt = createdAt,
+        _updatedAt = updatedAt,
+        _quotedMessageId = quotedMessageId;

  /// Create a new instance from a json
  factory Message.fromJson(Map<String, dynamic> json) => _$MessageFromJson(
        Serializer.moveToExtraDataFromRoot(json, topLevelFields),
+      ).copyWith(
+        status: MessageSendingStatus.sent,
      );

  /// The message ID. This is either created by Stream or set client side when
@@ -134,8 +137,10 @@ class Message extends Equatable {
  @JsonKey(toJson: Serializer.readOnly)
  final Message? quotedMessage;

+  final String? _quotedMessageId;
+
  /// The ID of the quoted message, if the message is a quoted reply.
-  final String? quotedMessageId;
+  String? get quotedMessageId => _quotedMessageId ?? quotedMessage?.id;

  /// Reserved field indicating the number of replies for this message.
  @JsonKey(includeIfNull: false, toJson: Serializer.readOnly)
@@ -162,13 +167,17 @@ class Message extends Equatable {
  @JsonKey(includeIfNull: false, toJson: Serializer.readOnly)
  final String? command;

+  final DateTime? _createdAt;
+
  /// Reserved field indicating when the message was created.
  @JsonKey(includeIfNull: false, toJson: Serializer.readOnly)
-  final DateTime createdAt;
+  DateTime get createdAt => _createdAt ?? DateTime.now();
+
+  final DateTime? _updatedAt;

  /// Reserved field indicating when the message was updated last time.
  @JsonKey(includeIfNull: false, toJson: Serializer.readOnly)
-  final DateTime updatedAt;
+  DateTime get updatedAt => _updatedAt ?? DateTime.now();

  /// User who sent the message
  @JsonKey(includeIfNull: false, toJson: Serializer.readOnly)
@@ -301,17 +310,17 @@ class Message extends Equatable {
      ownReactions: ownReactions ?? this.ownReactions,
      parentId: parentId ?? this.parentId,
      quotedMessage: quotedMessage ?? this.quotedMessage,
-      quotedMessageId: quotedMessageId ?? this.quotedMessageId,
+      quotedMessageId: quotedMessageId ?? _quotedMessageId,
      replyCount: replyCount ?? this.replyCount,
      threadParticipants: threadParticipants ?? this.threadParticipants,
      showInChannel: showInChannel ?? this.showInChannel,
      command: command ?? this.command,
-      createdAt: createdAt ?? this.createdAt,
+      createdAt: createdAt ?? _createdAt,
      silent: silent ?? this.silent,
      extraData: extraData ?? this.extraData,
      user: user ?? this.user,
      shadowed: shadowed ?? this.shadowed,
-      updatedAt: updatedAt ?? this.updatedAt,
+      updatedAt: updatedAt ?? _updatedAt,
      deletedAt: deletedAt ?? this.deletedAt,
      status: status ?? this.status,
      pinned: pinned ?? this.pinned,
@@ -126,7 +126,9 @@ class ThreadPage extends StatelessWidget {
            ),
          ),
          MessageInput(
-            parentMessage: parent,
+            messageInputController: MessageInputController(
+              message: Message(parentId: parent!.id),
+            ),
          ),
        ],
      ),
@@ -166,7 +166,9 @@ class ThreadPage extends StatelessWidget {
            ),
          ),
          MessageInput(
-            parentMessage: parent,
+            messageInputController: MessageInputController(
+              message: Message(parentId: parent!.id),
+            ),
          ),
        ],
      ),
@@ -27,9 +27,12 @@ dependencies:
  cupertino_icons: ^1.0.3
  flutter:
    sdk: flutter
-  stream_chat_flutter: ^2.2.1
-  stream_chat_localizations: ^1.1.0
-  stream_chat_persistence: ^2.2.0
+  stream_chat_flutter: 
+    path: ../
+  stream_chat_localizations: 
+    path: ../../stream_chat_localizations
+  stream_chat_persistence: 
+    path: ../../stream_chat_persistence

 dev_dependencies:
  flutter_test:
@@ -1,6 +1,6 @@
 import 'package:jiffy/jiffy.dart';
 import 'package:stream_chat_flutter/src/connection_status_builder.dart';
-import 'package:stream_chat_flutter/src/message_input.dart';
+import 'package:stream_chat_flutter/src/message_input/message_input.dart';
 import 'package:stream_chat_flutter/src/message_list_view.dart';
 import 'package:stream_chat_flutter/src/message_search_list_view.dart';
 import 'package:stream_chat_flutter_core/stream_chat_flutter_core.dart'
@@ -610,7 +610,9 @@ class _MessageActionsModalState extends State<MessageActionsModal> {
                widget.editMessageInputBuilder!(context, widget.message)
              else
                MessageInput(
-                  editMessage: widget.message,
+                  messageInputController: MessageInputController(
+                    message: widget.message,
+                  ),
                  preMessageSending: (m) {
                    FocusScope.of(context).unfocus();
                    Navigator.pop(context);
@@ -184,12 +184,9 @@ class MessageInput extends StatefulWidget {
    Key? key,
    this.onMessageSent,
    this.preMessageSending,
-    this.parentMessage,
-    this.editMessage,
    this.maxHeight = 150,
    this.keyboardType = TextInputType.multiline,
    this.disableAttachments = false,
-    this.initialMessage,
    this.messageInputController,
    this.actions = const [],
    this.actionsLocation = ActionsLocation.left,
@@ -219,18 +216,11 @@ class MessageInput extends StatefulWidget {
    this.attachmentsPickerBuilder,
    this.sendButtonBuilder,
    this.shouldKeepFocusAfterMessage,
-  })  : assert(
-          initialMessage == null || editMessage == null,
-          "Can't provide both `initialMessage` and `editMessage`",
-        ),
-        super(key: key);
+  }) : super(key: key);

  /// List of options for showing overlays
  final List<OverlayOptions> customOverlays;

-  /// Message to edit
-  final Message? editMessage;
-
  /// Video quality to use when compressing the videos
  final VideoQuality compressedVideoQuality;

@@ -242,9 +232,6 @@ class MessageInput extends StatefulWidget {
  /// do not set it if you're using our default CDN
  final int maxAttachmentSize;

-  /// Message to start with
-  final Message? initialMessage;
-
  /// Function called after sending the message
  final void Function(Message)? onMessageSent;

@@ -252,9 +239,6 @@ class MessageInput extends StatefulWidget {
  /// Use this to transform the message
  final FutureOr<Message> Function(Message)? preMessageSending;

-  /// Parent message in case of a thread
-  final Message? parentMessage;
-
  /// Maximum Height for the TextField to grow before it starts scrolling
  final double maxHeight;

@@ -367,11 +351,10 @@ class MessageInputState extends State<MessageInput> {
  final _imagePicker = ImagePicker();
  late final _focusNode = widget.focusNode ?? FocusNode();
  bool _inputEnabled = true;
-  bool _commandEnabled = false;
+  bool get _commandEnabled => messageInputController.value.command != null;
  bool _showCommandsOverlay = false;
  bool _showMentionsOverlay = false;

-  Command? _chosenCommand;
  bool _actionsShrunk = false;
  bool _openFilePickerSection = false;

@@ -382,16 +365,17 @@ class MessageInputState extends State<MessageInput> {
  late StreamChatThemeData _streamChatTheme;
  late MessageInputThemeData _messageInputTheme;

-  bool get _hasQuotedMessage => widget.quotedMessage != null;
+  bool get _hasQuotedMessage =>
+      messageInputController.value.quotedMessage != null;

  bool get _messageIsPresent => messageInputController.text.trim().isNotEmpty;

+  bool get _isEditing =>
+      messageInputController.value.status != MessageSendingStatus.sending;
+
  @override
  void initState() {
    super.initState();
-    if (widget.editMessage != null || widget.initialMessage != null) {
-      _parseExistingMessage(widget.editMessage ?? widget.initialMessage!);
-    }
    messageInputController.textEditingController
        .addListener(_onChangedDebounced);
    _focusNode.addListener(_focusNodeListener);
@@ -437,70 +421,74 @@ class MessageInputState extends State<MessageInput> {
  Widget build(BuildContext context) {
    Widget child = ValueListenableBuilder<Message>(
      valueListenable: messageInputController,
-      builder: (context, value, wid) => DecoratedBox(
-        decoration: BoxDecoration(
-          color: _messageInputTheme.inputBackgroundColor,
-        ),
-        child: SafeArea(
-          child: GestureDetector(
-            onPanUpdate: (details) {
-              if (details.delta.dy > 0) {
-                _focusNode.unfocus();
-                if (_openFilePickerSection) {
-                  setState(() {
-                    _openFilePickerSection = false;
-                  });
+      builder: (context, value, wid) {
+        print('VALUE ${value.text}');
+        return DecoratedBox(
+          decoration: BoxDecoration(
+            color: _messageInputTheme.inputBackgroundColor,
+          ),
+          child: SafeArea(
+            child: GestureDetector(
+              onPanUpdate: (details) {
+                if (details.delta.dy > 0) {
+                  _focusNode.unfocus();
+                  if (_openFilePickerSection) {
+                    setState(() {
+                      _openFilePickerSection = false;
+                    });
+                  }
                }
-              }
-            },
-            child: Column(
-              mainAxisSize: MainAxisSize.min,
-              children: [
-                if (_hasQuotedMessage)
-                  Padding(
-                    padding: const EdgeInsets.fromLTRB(8, 8, 8, 0),
-                    child: Row(
-                      mainAxisAlignment: MainAxisAlignment.spaceBetween,
-                      children: [
-                        Padding(
-                          padding: const EdgeInsets.all(8),
-                          child: StreamSvgIcon.reply(
-                            color: _streamChatTheme.colorTheme.disabled,
+              },
+              child: Column(
+                mainAxisSize: MainAxisSize.min,
+                children: [
+                  if (_hasQuotedMessage)
+                    Padding(
+                      padding: const EdgeInsets.fromLTRB(8, 8, 8, 0),
+                      child: Row(
+                        mainAxisAlignment: MainAxisAlignment.spaceBetween,
+                        children: [
+                          Padding(
+                            padding: const EdgeInsets.all(8),
+                            child: StreamSvgIcon.reply(
+                              color: _streamChatTheme.colorTheme.disabled,
+                            ),
                          ),
-                        ),
-                        Text(
-                          context.translations.replyToMessageLabel,
-                          style: const TextStyle(fontWeight: FontWeight.bold),
-                        ),
-                        IconButton(
-                          visualDensity: VisualDensity.compact,
-                          icon: StreamSvgIcon.closeSmall(),
-                          onPressed: widget.onQuotedMessageCleared,
-                        ),
-                      ],
+                          Text(
+                            context.translations.replyToMessageLabel,
+                            style: const TextStyle(fontWeight: FontWeight.bold),
+                          ),
+                          IconButton(
+                            visualDensity: VisualDensity.compact,
+                            icon: StreamSvgIcon.closeSmall(),
+                            onPressed: widget.onQuotedMessageCleared,
+                          ),
+                        ],
+                      ),
                    ),
-                  ),
-                Padding(
-                  padding: const EdgeInsets.symmetric(vertical: 8),
-                  child: _buildTextField(context),
-                ),
-                if (widget.parentMessage != null && !widget.hideSendAsDm)
                  Padding(
-                    padding: const EdgeInsets.only(
-                      right: 12,
-                      left: 12,
-                      bottom: 12,
-                    ),
-                    child: _buildDmCheckbox(),
+                    padding: const EdgeInsets.symmetric(vertical: 8),
+                    child: _buildTextField(context),
                  ),
-                _buildFilePickerSection(),
-              ],
+                  if (messageInputController.value.parentId != null &&
+                      !widget.hideSendAsDm)
+                    Padding(
+                      padding: const EdgeInsets.only(
+                        right: 12,
+                        left: 12,
+                        bottom: 12,
+                      ),
+                      child: _buildDmCheckbox(),
+                    ),
+                  _buildFilePickerSection(),
+                ],
+              ),
            ),
          ),
-        ),
-      ),
+        );
+      },
    );
-    if (widget.editMessage == null) {
+    if (_isEditing) {
      child = Material(
        elevation: 8,
        child: child,
@@ -575,10 +563,8 @@ class MessageInputState extends State<MessageInput> {
                    : _streamChatTheme.colorTheme.barsBg,
                child: InkWell(
                  onTap: () {
-                    setState(() {
-                      messageInputController.showInChannel =
-                          !messageInputController.showInChannel;
-                    });
+                    messageInputController.showInChannel =
+                        !messageInputController.showInChannel;
                  },
                  child: AnimatedCrossFade(
                    duration: const Duration(milliseconds: 300),
@@ -621,7 +607,7 @@ class MessageInputState extends State<MessageInput> {
      onSendMessage: sendMessage,
      timeOut: _timeOut,
      isIdle: !_messageIsPresent && messageInputController.attachments.isEmpty,
-      isEditEnabled: widget.editMessage != null,
+      isEditEnabled: _isEditing,
      idleSendButton: widget.idleSendButton,
      activeSendButton: widget.activeSendButton,
    );
@@ -668,7 +654,7 @@ class MessageInputState extends State<MessageInput> {
                  if (!widget.disableAttachments)
                    _buildAttachmentButton(context),
                  if (widget.showCommandsButton &&
-                      widget.editMessage == null &&
+                      !_isEditing &&
                      channel.state != null &&
                      channel.config?.commands.isNotEmpty == true)
                    _buildCommandButton(context),
@@ -791,7 +777,7 @@ class MessageInputState extends State<MessageInput> {
                          size: 16,
                        ),
                        Text(
-                          _chosenCommand?.name.toUpperCase() ?? '',
+                          messageInputController.value.command!.toUpperCase(),
                          style:
                              _streamChatTheme.textTheme.footnoteBold.copyWith(
                            color: Colors.white,
@@ -825,9 +811,7 @@ class MessageInputState extends State<MessageInput> {
                  height: 24,
                  width: 24,
                ),
-                onPressed: () {
-                  setState(() => _commandEnabled = false);
-                },
+                onPressed: messageInputController.clear,
              ),
            ),
          if (!_commandEnabled &&
@@ -848,8 +832,10 @@ class MessageInputState extends State<MessageInput> {

      final channel = StreamChannel.of(context).channel;
      if (value.isNotEmpty) {
-        // ignore: no-empty-block
-        channel.keyStroke(widget.parentMessage?.id).catchError((e) {});
+        channel
+            .keyStroke(messageInputController.value.parentId)
+            // ignore: no-empty-block
+            .catchError((e) {});
      }

      var actionsLength = widget.actions.length;
@@ -869,7 +855,7 @@ class MessageInputState extends State<MessageInput> {
  );

  String _getHint(BuildContext context) {
-    if (_commandEnabled && _chosenCommand!.name == 'giphy') {
+    if (_commandEnabled && messageInputController.value.command == 'giphy') {
      return context.translations.searchGifLabel;
    }
    if (messageInputController.attachments.isNotEmpty) {
@@ -1034,15 +1020,11 @@ class MessageInputState extends State<MessageInput> {
        splits[splits.length - 1] = user.name;
        final rejoin = splits.join('@');

-        messageInputController.textEditingController.value = TextEditingValue(
-          text: rejoin +
-              messageInputController.text.substring(
-                messageInputController.selectionStart,
-              ),
-          selection: TextSelection.collapsed(
-            offset: rejoin.length,
-          ),
-        );
+        messageInputController.text = rejoin +
+            messageInputController.text.substring(
+              messageInputController.selectionStart,
+            );
+
        _onChangedDebounced.cancel();
        setState(() => _showMentionsOverlay = false);
      },
@@ -1077,22 +1059,17 @@ class MessageInputState extends State<MessageInput> {
  void _chooseEmoji(List<String> splits, Emoji emoji) {
    final rejoin = splits.sublist(0, splits.length - 1).join(':') + emoji.char!;

-    messageInputController.textEditingController.value = TextEditingValue(
-      text: rejoin +
-          messageInputController.text.substring(
-            messageInputController.selectionStart,
-          ),
-      selection: TextSelection.collapsed(
-        offset: rejoin.length,
-      ),
-    );
+    messageInputController.text = rejoin +
+        messageInputController.text.substring(
+          messageInputController.selectionStart,
+        );
  }

  void _setCommand(Command c) {
-    messageInputController.clear();
+    messageInputController
+      ..clear()
+      ..command = c;
    setState(() {
-      _chosenCommand = c;
-      _commandEnabled = true;
      _showCommandsOverlay = false;
    });
  }
@@ -1133,9 +1110,7 @@ class MessageInputState extends State<MessageInput> {
                      (e) => ClipRRect(
                        borderRadius: BorderRadius.circular(10),
                        child: FileAttachment(
-                          message: Message(
-                            status: MessageSendingStatus.sending,
-                          ), // dummy message
+                          message: Message(), // dummy message
                          attachment: e,
                          size: Size(
                            MediaQuery.of(context).size.width * 0.65,
@@ -1202,9 +1177,11 @@ class MessageInputState extends State<MessageInput> {
          focusElevation: 0,
          hoverElevation: 0,
          onPressed: () {
-            setState(
-              () => messageInputController.attachments
-                  .removeWhere((e) => e.id == attachment.id),
+            messageInputController.value =
+                messageInputController.value.copyWith(
+              attachments: messageInputController.attachments
+                  .where((it) => it.id != attachment.id)
+                  .toList(),
            );
          },
          fillColor:
@@ -1412,7 +1389,7 @@ class MessageInputState extends State<MessageInput> {
  ///
  /// Note: Only meant to be used from outside the state.
  void addAttachment(Attachment attachment) {
-    setState(() => _addAttachments([attachment]));
+    _addAttachments([attachment]);
  }

  /// Adds an attachment to the [messageInputController.attachments] map
@@ -1539,23 +1516,20 @@ class MessageInputState extends State<MessageInput> {
      }
    }

-    setState(() {
-      _addAttachments([
-        attachment.copyWith(
-          file: file,
-          extraData: {...attachment.extraData}
-            ..update('file_size', ((_) => file!.size!)),
-        ),
-      ]);
-    });
+    _addAttachments([
+      attachment.copyWith(
+        file: file,
+        extraData: {...attachment.extraData}
+          ..update('file_size', ((_) => file!.size!)),
+      ),
+    ]);
  }

  /// Sends the current message
  Future<void> sendMessage() async {
-    var text = messageInputController.text.trim();
-    final attachments = messageInputController.attachments;
+    var message = messageInputController.value;

-    if (text.isEmpty && attachments.isEmpty) {
+    if (messageInputController.isValid) {
      return;
    }

@@ -1563,48 +1537,9 @@ class MessageInputState extends State<MessageInput> {

    shouldKeepFocus ??= !_commandEnabled;

-    if (_commandEnabled) {
-      text = '${'/${_chosenCommand!.name} '}$text';
-    }
-
-    messageInputController
-      ..text = ''
-      ..clearAttachments();
+    messageInputController.reset();
    widget.onQuotedMessageCleared?.call();

-    setState(() {
-      _commandEnabled = false;
-    });
-
-    Message message;
-    if (widget.editMessage != null) {
-      message = widget.editMessage!.copyWith(
-        text: text,
-        attachments: attachments,
-        mentionedUsers: messageInputController.mentionedUsers
-            .where((u) => text.contains('@${u.name}'))
-            .toList(),
-      );
-    } else {
-      message = (widget.initialMessage ?? Message()).copyWith(
-        parentId: widget.parentMessage?.id,
-        text: text,
-        attachments: attachments,
-        mentionedUsers: messageInputController.mentionedUsers
-            .where((u) => text.contains('@${u.name}'))
-            .toList(),
-        showInChannel: widget.parentMessage != null
-            ? messageInputController.showInChannel
-            : null,
-      );
-    }
-
-    if (widget.quotedMessage != null) {
-      message = message.copyWith(
-        quotedMessageId: widget.quotedMessage!.id,
-      );
-    }
-
    if (widget.preMessageSending != null) {
      message = await widget.preMessageSending!(message);
    }
@@ -1615,13 +1550,9 @@ class MessageInputState extends State<MessageInput> {
      await streamChannel.reloadChannel();
    }

-    messageInputController.clearMentionedUsers();
-
    try {
      Future sendingFuture;
-      if (widget.editMessage == null ||
-          widget.editMessage!.status == MessageSendingStatus.failed ||
-          widget.editMessage!.status == MessageSendingStatus.sending) {
+      if (!_isEditing) {
        sendingFuture = channel.sendMessage(message);
      } else {
        sendingFuture = channel.updateMessage(message);
@@ -1635,7 +1566,7 @@ class MessageInputState extends State<MessageInput> {

      final resp = await sendingFuture;
      if (resp.message?.type == 'error') {
-        _parseExistingMessage(message);
+        messageInputController.value = message;
      }
      _startSlowMode();
      widget.onMessageSent?.call(resp.message);
@@ -1714,12 +1645,6 @@ class MessageInputState extends State<MessageInput> {
    );
  }

-  void _parseExistingMessage(Message message) {
-    final messageText = message.text;
-    if (messageText != null) messageInputController.text = messageText;
-    _addAttachments(message.attachments);
-  }
-
  @override
  void dispose() {
    messageInputController.textEditingController
@@ -1731,19 +1656,12 @@ class MessageInputState extends State<MessageInput> {
    super.dispose();
  }

-  bool _initialized = false;
-
  @override
  void didChangeDependencies() {
    _streamChatTheme = StreamChatTheme.of(context);
    _messageInputTheme = MessageInputTheme.of(context);
-    if (widget.editMessage == null && _timeOut <= 0) _startSlowMode();
+    if (!_isEditing && _timeOut <= 0) _startSlowMode();

-    if ((widget.editMessage != null || widget.initialMessage != null) &&
-        !_initialized) {
-      FocusScope.of(context).requestFocus(_focusNode);
-      _initialized = true;
-    }
    super.didChangeDependencies();
  }
 }
@@ -116,8 +116,8 @@ class _StreamAttachmentPickerState extends State<StreamAttachmentPicker> {

  @override
  Widget build(BuildContext context) {
-    var _streamChatTheme = StreamChatTheme.of(context);
-    var messageInputController = widget.messageInputController;
+    final _streamChatTheme = StreamChatTheme.of(context);
+    final messageInputController = widget.messageInputController;

    final _attachmentContainsImage =
        messageInputController.attachments.any((it) => it.type == 'image');
@@ -23,7 +23,7 @@ class StreamMessageSendButton extends StatelessWidget {

  @override
  Widget build(BuildContext context) {
-    var _streamChatTheme = StreamChatTheme.of(context);
+    final _streamChatTheme = StreamChatTheme.of(context);

    late Widget sendButton;
    if (timeOut > 0) {
@@ -46,7 +46,7 @@ class StreamMessageSendButton extends StatelessWidget {
  }

  Widget _buildIdleSendButton(BuildContext context) {
-    var _messageInputTheme = MessageInputTheme.of(context);
+    final _messageInputTheme = MessageInputTheme.of(context);

    return Padding(
      padding: const EdgeInsets.all(8),
@@ -58,7 +58,7 @@ class StreamMessageSendButton extends StatelessWidget {
  }

  Widget _buildSendButton(BuildContext context) {
-    var _messageInputTheme = MessageInputTheme.of(context);
+    final _messageInputTheme = MessageInputTheme.of(context);

    return Padding(
      padding: const EdgeInsets.all(8),
@@ -1,3 +1,5 @@
+// ignore_for_file: prefer-trailing-comma, cascade_invocations
+
 import 'dart:ui' as ui show BoxHeightStyle, BoxWidthStyle;

 import 'package:flutter/cupertino.dart';
@@ -2,7 +2,7 @@ import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart' hide TextTheme;
 import 'package:stream_chat_flutter/src/channel_preview.dart';
 import 'package:stream_chat_flutter/src/gradient_avatar.dart';
-import 'package:stream_chat_flutter/src/message_input.dart';
+import 'package:stream_chat_flutter/src/message_input/message_input.dart';
 import 'package:stream_chat_flutter/src/reaction_icon.dart';
 import 'package:stream_chat_flutter/src/theme/themes.dart';
 import 'package:stream_chat_flutter/stream_chat_flutter.dart';
@@ -23,16 +23,16 @@ export 'src/localization/stream_chat_localizations.dart';
 export 'src/localization/translations.dart' show DefaultTranslations;
 export 'src/mention_tile.dart';
 export 'src/message_action.dart';
-export 'src/message_input.dart';
+export 'src/message_input/message_input.dart';
 export 'src/message_list_view.dart';
 export 'src/message_search_item.dart';
 export 'src/message_search_list_view.dart';
 export 'src/message_text.dart';
 export 'src/message_widget.dart';
-export 'src/mip/countdown_button.dart';
-export 'src/mip/stream_attachment_picker.dart';
-export 'src/mip/stream_message_send_button.dart';
-export 'src/mip/stream_message_text_field.dart';
+export 'src/message_input/countdown_button.dart';
+export 'src/message_input/stream_attachment_picker.dart';
+export 'src/message_input/stream_message_send_button.dart';
+export 'src/message_input/stream_message_text_field.dart';
 export 'src/option_list_tile.dart';
 export 'src/reaction_icon.dart';
 export 'src/reaction_picker.dart';
@@ -4,29 +4,82 @@ import 'package:flutter/material.dart';
 import 'package:flutter/widgets.dart';
 import 'package:stream_chat/stream_chat.dart';

+typedef MessageValidator = bool Function(Message message);
+
 /// Controller for storing and mutating a [Message] value.
 class MessageInputController extends ValueNotifier<Message> {
  /// Creates a controller for an editable text field.
  ///
  /// This constructor treats a null [message] argument as if it were the empty
  /// message.
-  factory MessageInputController({Message? message}) =>
-      MessageInputController._(message ?? Message());
+  factory MessageInputController({
+    Message? message,
+    MessageValidator? validator,
+  }) =>
+      MessageInputController._(
+        initialMessage: message ?? Message(),
+        validator: validator ?? _defaultValidator,
+      );

  /// Creates a controller for an editable text field from an initial [text].
-  factory MessageInputController.fromText(String? text) =>
-      MessageInputController._(Message(text: text));
+  factory MessageInputController.fromText(
+    String? text, {
+    MessageValidator? validator,
+  }) =>
+      MessageInputController._(
+        initialMessage: Message(text: text),
+        validator: validator ?? _defaultValidator,
+      );

  /// Creates a controller for an editable text field from an initial
  /// [attachments].
  factory MessageInputController.fromAttachments(
-    List<Attachment> attachments,
-  ) =>
-      MessageInputController._(Message(attachments: attachments));
+    List<Attachment> attachments, {
+    MessageValidator? validator,
+  }) =>
+      MessageInputController._(
+        initialMessage: Message(attachments: attachments),
+        validator: validator ?? _defaultValidator,
+      );

-  MessageInputController._(Message message)
-      : _textEditingController = TextEditingController(text: message.text),
-        super(message);
+  MessageInputController._({
+    required Message initialMessage,
+    this.validator = _defaultValidator,
+  })  : _textEditingController =
+            TextEditingController(text: initialMessage.text),
+        _initialMessage = initialMessage,
+        super(initialMessage) {
+    addListener(_textEditingSyncer);
+  }
+
+  /// A callback function that validates the message.
+  final MessageValidator validator;
+
+  /// Checks if the message is valid.
+  bool get isValid => validator(value);
+
+  static bool _defaultValidator(Message message) =>
+      message.text?.isNotEmpty != true && message.attachments.isEmpty;
+
+  void _textEditingSyncer() {
+    final cleanText = value.command == null
+        ? value.text
+        : value.text?.replaceFirst(
+            '/${value.command} ',
+            '',
+          );
+
+    if (cleanText != _textEditingController.text) {
+      final previousOffset = _textEditingController.value.selection.start;
+      final previousText = _textEditingController.text;
+      final diff = (cleanText?.length ?? 0) - previousText.length;
+      _textEditingController
+        ..text = cleanText ?? ''
+        ..selection = TextSelection.collapsed(
+          offset: previousOffset + diff,
+        );
+    }
+  }

  ///
  TextEditingController get textEditingController => _textEditingController;
@@ -35,24 +88,29 @@ class MessageInputController extends ValueNotifier<Message> {
  ///
  String get text => _textEditingController.text;

+  final Message _initialMessage;
+
  ///
  set message(Message message) {
    value = message;
  }

-  set text(String newText) {
-    value = value.copyWith(text: newText);
-    _textEditingController
-      ..text = newText
-      ..selection = TextSelection.fromPosition(
-        TextPosition(offset: _textEditingController.text.length),
-      );
+  ///
+  set command(Command command) {
+    value = value.copyWith(
+      command: command.name,
+      text: '/${command.name} ',
+    );
  }

-  ///
-  set textEditingValue(TextEditingValue newValue) {
-    _textEditingController.value = newValue;
-    value = value.copyWith(text: _textEditingController.text);
+  set text(String newText) {
+    var newTextWithCommand = newText;
+    if (value.command != null) {
+      if (!newText.startsWith('/${value.command}')) {
+        newTextWithCommand = '/${value.command} $newText';
+      }
+    }
+    value = value.copyWith(text: newTextWithCommand);
  }

  ///
@@ -147,9 +205,13 @@ class MessageInputController extends ValueNotifier<Message> {
    _textEditingController.clear();
  }

+  /// Set the [value] to the initial [Message] value.
+  void reset() => value = _initialMessage;
+
  @override
  void dispose() {
    super.dispose();
+    removeListener(_textEditingSyncer);
    _textEditingController.dispose();
  }
 }