dart/lib/components/slidelist.dart

// Copyright 2015 The Vanadium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

import 'package:flutter/material.dart';

import '../models/all.dart' as model;
import '../stores/store.dart';
import '../styles/common.dart' as style;
import '../utils/image_provider.dart' as image_provider;
import 'slideshow.dart';
import 'syncslides_page.dart';
import 'toast.dart' as toast;

final GlobalKey _scaffoldKey = new GlobalKey();

class SlideListPage extends SyncSlidesPage {
  final String _deckId;

  SlideListPage(this._deckId);

  @override
  Widget build(BuildContext context, AppState appState, AppActions appActions) {
    if (!appState.decks.containsKey(_deckId)) {
      // TODO(aghassemi): Proper error page with navigation back to main view.
      return new Text('Deck no longer exists.');
    }
    var deckState = appState.decks[_deckId];
    var slides = deckState.slides;
    var toolbarActions = [];
    var deleteAction = _buildDelete(context, appState, appActions);
    if (deleteAction != null) {
      toolbarActions.add(deleteAction);
    }
    return new Scaffold(
        key: _scaffoldKey,
        appBar: new AppBar(
            leading: new IconButton(
                icon: Icons.arrow_back,
                onPressed: () => Navigator.pop(context)),
            title: new Text(deckState.deck.name),
            actions: toolbarActions),
        floatingActionButton: _buildFab(context, appState, appActions),
        body: new Material(child: new SlideList(_deckId, slides, appActions)));
  }

  IconButton _buildDelete(
      BuildContext context, AppState appState, AppActions appActions) {
    var deckState = appState.decks[_deckId];
    if (deckState.presentation != null) {
      // Can't delete while in a presentation.
      return null;
    }

    return new IconButton(
        icon: Icons.delete,
        onPressed: () async {
          await appActions.removeDeck(deckState.deck.key);
          Navigator.pop(context);
        });
  }

  FloatingActionButton _buildFab(
      BuildContext context, AppState appState, AppActions appActions) {
    var deckState = appState.decks[_deckId];

    if (deckState.presentation == null) {
      return new FloatingActionButton(
          child: new Icon(icon: Icons.play_arrow),
          onPressed: () async {
            toast.info(_scaffoldKey, 'Starting presentation...',
                duration: toast.Durations.permanent);

            try {
              await appActions.startPresentation(_deckId);
              toast.info(_scaffoldKey, 'Presentation started.');

              Navigator.push(
                  context,
                  new MaterialPageRoute(
                      builder: (context) => new SlideshowPage(_deckId)));
            } catch (e) {
              toast.error(_scaffoldKey, 'Failed to start presentation.', e);
            }
          });
    }

    // Already presenting own deck, allow for stopping it.
    if (deckState.presentation != null && deckState.presentation.isOwner) {
      var key = deckState.presentation.key;
      return new FloatingActionButton(
          child: new Icon(icon: Icons.stop),
          onPressed: () async {
            toast.info(_scaffoldKey, 'Stopping presentation...',
                duration: toast.Durations.permanent);

            try {
              await appActions.stopPresentation(key);
              toast.info(_scaffoldKey, 'Presentation stopped.');
            } catch (e) {
              toast.error(_scaffoldKey, 'Failed to stop presentation.', e);
            }
          });
    }

    return null;
  }
}

class SlideList extends StatelessWidget {
  String _deckId;
  List<model.Slide> _slides = new List<model.Slide>();
  AppActions _appActions;
  SlideList(this._deckId, this._slides, this._appActions);

  @override
  Widget build(BuildContext context) {
    Iterable<Widget> items = _slides.map(
        (slide) => _buildSlide(context, _deckId, slide.num, slide, onTap: () {
              _appActions.setCurrSlideNum(_deckId, slide.num);

              Navigator.push(
                  context,
                  new MaterialPageRoute(
                      builder: (context) => new SlideshowPage(_deckId)));
            }));

    return new ScrollableList(
        itemExtent: style.Size.listHeight, children: items);
  }
}

Widget _buildSlide(
    BuildContext context, String deckId, int slideIndex, model.Slide slideData,
    {Function onTap}) {
  var thumbnail = new AsyncImage(
      provider: image_provider.getSlideImage(deckId, slideData),
      fit: ImageFit.cover,
      width: style.Size.slideListThumbnailWidth);

  thumbnail = new Flexible(child: new Container(child: thumbnail), flex: 0);

  var title =
      new Text('Slide ${slideIndex + 1}', style: style.Text.subtitleStyle);
  var notes = new Text(
      'This is the teaser slide. It should be memorable and descriptive.');
  var titleAndNotes = new Flexible(child: new Container(
      child: new Column(
          children: [title, notes],
          crossAxisAlignment: CrossAxisAlignment.start),
      padding: style.Spacing.normalPadding));

  var card = new Container(
      child: new Container(
          margin: style.Spacing.cardMargin,
          child: new Material(
              elevation: 2,
              child: new Row(children: [thumbnail, titleAndNotes]))),
      margin: style.Spacing.listItemMargin);

  var listItem = new InkWell(
      key: new Key(slideIndex.toString()), child: card, onTap: onTap);

  return listItem;
}