actions-test/lib/screens/room/main.dart

import 'package:flutter/material.dart';
import 'package:outbag_app/backend/request.dart';
import 'package:outbag_app/backend/room.dart';
import 'package:outbag_app/backend/user.dart';
import 'package:outbag_app/screens/room/pages/about.dart';
import 'package:outbag_app/screens/room/pages/categories.dart';
import 'package:outbag_app/screens/room/pages/products.dart';
import 'package:outbag_app/screens/room/pages/list.dart';
import 'package:outbag_app/tools/fetch_wrapper.dart';
import 'package:provider/provider.dart';
import 'package:routemaster/routemaster.dart';

class RoomPage extends StatefulWidget {
  final String server;
  final String tag;

  const RoomPage(this.server, this.tag, {super.key});

  @override
  State<StatefulWidget> createState() => _RoomPageState();
}

class _RoomPageState extends State<RoomPage> {
  RoomInfo? info;
  Room? room;

  final PageController _ctr = PageController(initialPage: 0);
  int page = 0;

  // fetch room information
  void fetchInfo() async {
    final sm = ScaffoldMessenger.of(context);
    final user = context.read<User>();

    try {
      final diskRoom =
      await Room.fromDisk(serverTag: widget.server, id: widget.tag);
      setState(() {
          room = diskRoom;
      });
    } catch (_) {}

    doNetworkRequest(sm,
      req: () => postWithCreadentials(
        path: 'getRoomInfo',
        credentials: user,
        target: user.server,
        body: {'room': widget.tag, 'server': widget.server}),
      onOK: (body) async {
        final info = RoomInfo.fromJSON(body['data']);
        final room = Room.fromJSON(body['data']);

        room.toDisk();

        setState(() {
            this.info = info;
        });
        return true;
      },
      onNetworkErr: () {
        // user offline
        if (room == null) {
          // no room data available
          // NOTE: close room?
        }
        return true;
      },
      onServerErr: (json) {
        // user no longer in room
        // TODO: close room
        return true;
    });
  }

  @override
  void initState() {
    super.initState();

    _ctr.addListener(() {
        setState(() {
            page = _ctr.page?.toInt() ?? _ctr.initialPage;
        });
    });

    Room.listen((_) async {
        // rooms changed on disk
        // probably this one,
        // because it is currently open
        // NOTE: might be a different room
        // (if a background listener is implemented at some point,
        // checking if this room changed might improve performance)
        try {
          final r = await Room.fromDisk(serverTag: widget.server, id: widget.tag);
          setState(() {
              room = r;
          });
        } catch (_) {}
    });

    WidgetsBinding.instance.addPostFrameCallback((_) => fetchInfo());
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(room?.name ?? 'Unknown Room'),
        leading: IconButton(
          onPressed: () {
            // go back
            Routemaster.of(context).history.back();
          },
          icon: const Icon(Icons.arrow_back),
          tooltip: "Go back",
        ),
      ),
      body: PageView(
        controller: _ctr,
        children: [
          ShoppingListPage(room, info),
          RoomProductsPage(room, info),
          RoomCategoriesPage(room, info),
          AboutRoomPage(room, info)
        ],
      ),
      bottomNavigationBar: NavigationBar(
        onDestinationSelected: (int index) {
          _ctr.animateToPage(index,
            curve: Curves.easeInOut,
            duration: const Duration(milliseconds: 300));
        },
        selectedIndex: page,
        destinations: const [
          NavigationDestination(
            icon: Icon(Icons.list),
            label: "List",
            tooltip: 'View shopping list'),
          NavigationDestination(
            icon: Icon(Icons.inventory_2),
            label: "Products",
            tooltip: 'View saved items'),
          NavigationDestination(
            icon: Icon(Icons.category),
            label: "Categories",
            tooltip: 'View categories'),
          NavigationDestination(
            icon: Icon(Icons.info_rounded),
            label: "About",
            tooltip: 'View room info'),
        ],
      ),
    );
  }
}