frosty/lib/widgets/chat.dart

import 'package:flutter/material.dart';
import 'package:flutter_mobx/flutter_mobx.dart';
import 'package:frosty/stores/auth_store.dart';
import 'package:frosty/stores/chat_store.dart';
import 'package:frosty/widgets/chat_stats.dart';
import 'package:provider/provider.dart';

class Chat extends StatefulWidget {
  final ChatStore chatStore;

  const Chat({Key? key, required this.chatStore}) : super(key: key);

  @override
  _ChatState createState() => _ChatState();
}

class _ChatState extends State<Chat> {
  @override
  Widget build(BuildContext context) {
    return FutureBuilder(
      future: widget.chatStore.getAssets(),
      builder: (_, snapshot) {
        if (snapshot.connectionState == ConnectionState.done) {
          return Column(
            children: [
              Expanded(
                child: Stack(
                  alignment: AlignmentDirectional.bottomCenter,
                  children: [
                    Observer(
                      builder: (_) {
                        return ListView.builder(
                          addAutomaticKeepAlives: false,
                          addRepaintBoundaries: false,
                          itemCount: widget.chatStore.messages.length,
                          controller: widget.chatStore.scrollController,
                          padding: const EdgeInsets.all(5.0),
                          itemBuilder: (context, index) {
                            return widget.chatStore.renderChatMessage(widget.chatStore.messages[index]);
                          },
                        );
                      },
                    ),
                    Observer(
                      builder: (_) {
                        return Visibility(
                          visible: !widget.chatStore.autoScroll,
                          child: Container(
                            padding: const EdgeInsets.symmetric(horizontal: 4.0),
                            width: double.infinity,
                            child: ElevatedButton(
                              onPressed: widget.chatStore.resumeScroll,
                              child: const Text('Resume Scroll'),
                            ),
                          ),
                        );
                      },
                    ),
                  ],
                ),
              ),
              Row(
                children: [
                  IconButton(
                    icon: const Icon(Icons.stacked_bar_chart),
                    onPressed: () {
                      showModalBottomSheet(
                        context: context,
                        builder: (context) {
                          return ChatStats(
                            chatStore: widget.chatStore,
                          );
                        },
                      );
                    },
                  ),
                  if (context.read<AuthStore>().isLoggedIn)
                    Expanded(
                      child: Padding(
                        padding: const EdgeInsets.all(8.0),
                        child: TextField(
                          decoration: const InputDecoration(
                            isDense: true,
                            contentPadding: EdgeInsets.all(8.0),
                            border: OutlineInputBorder(
                              borderRadius: BorderRadius.all(Radius.circular(5.0)),
                            ),
                            hintText: 'Send a message',
                          ),
                          controller: widget.chatStore.textController,
                          onSubmitted: (string) => widget.chatStore.sendMessage(string),
                        ),
                      ),
                    ),
                ],
              )
            ],
          );
        }
        return const Center(
          child: CircularProgressIndicator(),
        );
      },
    );
  }

  @override
  void dispose() {
    widget.chatStore.dispose();
    super.dispose();
  }
}