import 'package:comunic/helpers/preferences_helper.dart';
import 'package:comunic/helpers/users_helper.dart';
import 'package:comunic/models/user.dart';
import 'package:comunic/ui/routes/push_notifications_route.dart';
import 'package:comunic/ui/routes/settings/account_image_settings.dart';
import 'package:comunic/ui/widgets/account_image_widget.dart';
import 'package:comunic/ui/widgets/async_screen_widget.dart';
import 'package:comunic/ui/widgets/login_routes_theme.dart';
import 'package:comunic/utils/account_utils.dart';
import 'package:comunic/utils/intl_utils.dart';
import 'package:flutter/material.dart';

/// Tour route
///
/// The tour is shown when the client sign into the application
///
/// @author Pierre Hubert

Future<void> showTour(BuildContext context) async => await Navigator.of(context)
    .push(MaterialPageRoute(builder: (c) => TourRoute()));

class TourRoute extends StatefulWidget {
  @override
  _TourRouteState createState() => _TourRouteState();
}

class _TourRouteState extends State<TourRoute> {
  final key = GlobalKey<AsyncScreenWidgetState>();
  final _pushNotificationsKey =
      GlobalKey<PushNotificationsConfigurationWidgetState>();

  User currUser;

  int _defaultIndex = 0;

  Future<void> _init() async {
    currUser =
        await UsersHelper().getSingleWithThrow(userID(), forceDownload: true);
  }

  List<Widget> get _list => [
        _FirstPane(),

        // Account image
        _PresentationPane(
          iconWidget: AccountImageWidget(user: currUser, width: 50),
          title: tr("Account image"),
          text: tr(
              "Account image allow to quickly recognize people.\n\nYou can decide to define one now!"),
          actionTitle: tr("Upload an account image"),
          onActionTap: (ctx) async {
            await uploadNewAccountImage(context);
            _defaultIndex = DefaultTabController.of(ctx).index;
            await key.currentState.refresh();
          },
        ),

        // Notifications
        _PresentationPane(
          icon: Icons.notifications,
          title: tr("Push notifications"),
          child: (c) => PushNotificationsConfigurationWidget(
            key: _pushNotificationsKey,
            onConfigured: () => setState(() {}),
            onChanged: () => setState(() {}),
          ),
          canGoNext: _pushNotificationsKey?.currentState?.canSubmit ?? false,
          onTapNext: (c) => _pushNotificationsKey.currentState.submit(),
        ),

        _PresentationPane(
          icon: Icons.group_add,
          title: tr("Friends"),
          text: tr(
              "You can search the people you know and ask them to become your friends!\n\nThis will help you to reach them to exchange information!"),
        ),
        _PresentationPane(
          icon: Icons.question_answer,
          title: tr("Conversations"),
          text: tr(
              "With Comunic, you can have conversations with all your friends.\n\nIt is also possible to make video calls!"),
        ),
        _PresentationPane(
          icon: Icons.group,
          title: tr("Groups"),
          text: tr(
              "You can join groups where people share the same interests as you!\n\nIt is also easy to create your own groups!"),
        ),
        _PresentationPane(
          icon: Icons.lock,
          title: tr("Privacy"),
          text: tr(
              "Your data is YOUR DATA. We will never use it or sell it.\n\nIf you do not trust us, you can always check out our source code to verify it!"),
        ),
        _LastPane(),
      ];

  @override
  Widget build(BuildContext context) => LoginRoutesTheme(
        child: Scaffold(
          body: SafeArea(
            child: AsyncScreenWidget(
              key: key,
              onReload: _init,
              errorMessage: tr("Failed to load tour!"),
              onBuild: () => DefaultTabController(
                initialIndex: _defaultIndex,
                length: _list.length,
                child: _RouteBody(
                  panes: _list,
                ),
              ),
            ),
          ),
        ),
      );
}

class _RouteBody extends StatefulWidget {
  final List<Widget> panes;

  const _RouteBody({Key key, this.panes}) : super(key: key);

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

class __RouteBodyState extends State<_RouteBody> {
  TabController _controller;

  bool get _isLastPane => _controller.index >= widget.panes.length - 1;

  _PresentationPane get _currPane =>
      widget.panes[_controller.index] is _PresentationPane
          ? widget.panes[_controller.index]
          : null;

  bool get _canGoNext => _currPane?.canGoNext ?? true;

  @override
  void didUpdateWidget(_RouteBody oldWidget) {
    super.didUpdateWidget(oldWidget);
    _updateController();
  }

  @override
  void didChangeDependencies() {
    super.didChangeDependencies();
    _updateController();
  }

  void _updateController() {
    _controller = DefaultTabController.of(context);
    _controller.addListener(() => setState(() {}));
  }

  @override
  Widget build(BuildContext context) => Padding(
        padding: const EdgeInsets.all(8.0),
        child: Column(
          children: <Widget>[
            Spacer(flex: 1),
            Expanded(
                child: TabBarView(
                  children: widget.panes,
                  physics: NeverScrollableScrollPhysics(),
                ),
                flex: 10),
            Spacer(flex: 1),
            TabPageSelector(selectedColor: Colors.white),
            Spacer(flex: 1),
            OutlinedButton(
              onPressed: _canGoNext ? _nextOrFinish : null,
              child: Text(!_isLastPane ? tr("Next") : tr("Let's go!")),
            ),
            Spacer(flex: 1),
          ],
        ),
      );

  void _nextOrFinish() async {
    if (_controller.indexIsChanging) return;

    if (!_isLastPane) {
      // Check if the next click has to be captured
      if (_currPane?.onTapNext != null) {
        if (!await _currPane.onTapNext(context)) return;
      }

      _controller.animateTo(_controller.index + 1);
    } else {
      (await PreferencesHelper.getInstance())
          .setBool(PreferencesKeyList.IS_TOUR_SEEN, true);
      Navigator.of(context).pop();
    }
  }
}

class _PresentationPane extends StatelessWidget {
  final IconData icon;
  final Widget iconWidget;
  final String title;
  final String text;
  final Function(BuildContext) child;
  final String actionTitle;
  final Function(BuildContext) onActionTap;
  final bool canGoNext;
  final Future<bool> Function(BuildContext) onTapNext;

  const _PresentationPane({
    Key key,
    this.icon,
    this.iconWidget,
    @required this.title,
    this.text,
    this.child,
    this.actionTitle,
    this.onActionTap,
    this.canGoNext = true,
    this.onTapNext,
  })  : assert(icon != null || iconWidget != null),
        assert(title != null),
        assert(text != null || child != null),
        super(key: key);

  bool get _hasAction => actionTitle != null && onActionTap != null;

  @override
  Widget build(BuildContext context) {
    if (text != null)
      return Column(
        children: <Widget>[
          Spacer(flex: 3),
          icon != null ? Icon(icon, color: Colors.white, size: 50) : iconWidget,
          Spacer(flex: 1),
          Text(
            title,
            style: TextStyle(fontSize: 20),
          ),
          Spacer(flex: 1),
          _FixedSizeTextArea(text),
          Spacer(flex: 1),
          _hasAction
              ? OutlinedButton(
                  onPressed: () => onActionTap(context),
                  child: Text(
                    actionTitle,
                    style: TextStyle(color: Colors.white),
                  ),
                )
              : Opacity(
                  opacity: 0,
                  child: OutlinedButton(
                    onPressed: null,
                    child: Text(""),
                  ),
                ),
          Spacer(flex: 3),
        ],
      );

    return Column(
      children: <Widget>[
        Spacer(flex: 1),
        icon != null ? Icon(icon, color: Colors.white, size: 50) : iconWidget,
        Spacer(flex: 1),
        Text(
          title,
          style: TextStyle(fontSize: 20),
        ),
        Spacer(flex: 1),
        ConstrainedBox(
            constraints: BoxConstraints(maxHeight: 300),
            child: SingleChildScrollView(child: child(context))),
        Spacer(flex: 1),
      ],
    );
  }
}

class _FirstPane extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Column(
      mainAxisAlignment: MainAxisAlignment.center,
      children: <Widget>[
        Spacer(flex: 3),
        Text(
          "Comunic",
          style: TextStyle(fontSize: 25),
        ),
        Spacer(flex: 2),
        _FixedSizeTextArea(tr(
            "Welcome to Comunic, the social network that respect your privacy !")),
        Spacer(flex: 1),
        _FixedSizeTextArea(tr(
            "Let's configure a few things and present you some features of the network...")),
        Spacer(flex: 3),
      ],
    );
  }
}

class _LastPane extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Center(
      child: Text(
        tr("The application is yours"),
        style: TextStyle(fontSize: 25),
      ),
    );
  }
}

class _FixedSizeTextArea extends StatelessWidget {
  final String text;

  const _FixedSizeTextArea(this.text);

  @override
  Widget build(BuildContext context) => ConstrainedBox(
        constraints: BoxConstraints(maxWidth: 300),
        child: Text(text, textAlign: TextAlign.justify),
      );
}