ente/lib/ui/memories_widget.dart

import 'package:flutter/material.dart';
import 'package:flutter/widgets.dart';
import 'package:flutter_swiper/flutter_swiper.dart';
import 'package:photos/memories_service.dart';
import 'package:photos/models/file_type.dart';
import 'package:photos/models/memory.dart';
import 'package:photos/ui/thumbnail_widget.dart';
import 'package:photos/ui/video_widget.dart';
import 'package:photos/ui/zoomable_image.dart';
import 'package:photos/utils/date_time_util.dart';
import 'package:photos/utils/share_util.dart';

class MemoriesWidget extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return FutureBuilder<List<Memory>>(
      future: MemoriesService.instance.getMemories(),
      builder: (context, snapshot) {
        if (snapshot.hasError ||
            !snapshot.hasData ||
            snapshot.data.length == 0) {
          return Container();
        } else {
          return _buildMemories(snapshot.data);
        }
      },
    );
  }

  Widget _buildMemories(List<Memory> memories) {
    final collatedMemories = _collateMemories(memories);
    final memoryWidgets = List<Widget>();
    for (final memories in collatedMemories) {
      memoryWidgets.add(MemoryWidget(memories: memories));
    }
    return Row(children: memoryWidgets);
  }

  List<List<Memory>> _collateMemories(List<Memory> memories) {
    final yearlyMemories = List<Memory>();
    final collatedMemories = List<List<Memory>>();
    for (int index = 0; index < memories.length; index++) {
      if (index > 0 &&
          !_areMemoriesFromSameYear(memories[index - 1], memories[index])) {
        final collatedYearlyMemories = List<Memory>();
        collatedYearlyMemories.addAll(yearlyMemories);
        collatedMemories.add(collatedYearlyMemories);
        yearlyMemories.clear();
      }
      yearlyMemories.add(memories[index]);
    }
    if (yearlyMemories.isNotEmpty) {
      collatedMemories.add(yearlyMemories);
    }
    return collatedMemories;
  }

  bool _areMemoriesFromSameYear(Memory first, Memory second) {
    var firstDate =
        DateTime.fromMicrosecondsSinceEpoch(first.file.creationTime);
    var secondDate =
        DateTime.fromMicrosecondsSinceEpoch(second.file.creationTime);
    return firstDate.year == secondDate.year;
  }
}

class MemoryWidget extends StatelessWidget {
  const MemoryWidget({
    Key key,
    @required this.memories,
  }) : super(key: key);

  final List<Memory> memories;

  @override
  Widget build(BuildContext context) {
    final title = _getTitle(memories[0]);
    return GestureDetector(
      onTap: () {
        Navigator.of(context).push(
          MaterialPageRoute(
            builder: (BuildContext context) {
              return FullScreenMemory(memories, title);
            },
          ),
        );
      },
      child: Container(
        width: 100,
        height: 120,
        child: Padding(
          padding: const EdgeInsets.all(8.0),
          child: Column(
            children: [
              ClipOval(
                child: Container(
                  width: 76,
                  height: 76,
                  child: Hero(
                    tag: "memories" + memories[0].file.tag(),
                    child: ThumbnailWidget(memories[0].file),
                  ),
                ),
              ),
              Padding(padding: EdgeInsets.all(2)),
              Text(title),
            ],
          ),
        ),
      ),
    );
  }

  String _getTitle(Memory memory) {
    final present = DateTime.now();
    final then = DateTime.fromMicrosecondsSinceEpoch(memory.file.creationTime);
    final diffInYears = present.year - then.year;
    if (diffInYears == 1) {
      return "1 year ago";
    } else {
      return diffInYears.toString() + " years ago";
    }
  }
}

class FullScreenMemory extends StatefulWidget {
  final List<Memory> memories;
  final String title;

  FullScreenMemory(this.memories, this.title, {Key key}) : super(key: key);

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

class _FullScreenMemoryState extends State<FullScreenMemory> {
  double _opacity = 0;

  @override
  void initState() {
    super.initState();
    Future.delayed(Duration(milliseconds: 300), () {
      setState(() {
        _opacity = 1;
      });
    });
    Future.delayed(Duration(seconds: 3), () {
      setState(() {
        _opacity = 0;
      });
    });
  }

  @override
  Widget build(BuildContext context) {
    return Material(
      type: MaterialType.transparency,
      child: Container(
        child: Stack(children: [
          Swiper(
            itemBuilder: (BuildContext context, int index) {
              final file = widget.memories[index].file;
              return Stack(children: [
                file.fileType == FileType.image
                    ? ZoomableImage(
                        file,
                        tagPrefix: "memories",
                      )
                    : VideoWidget(file, tagPrefix: "memories"),
                Padding(
                  padding: const EdgeInsets.fromLTRB(16, 40, 16, 16),
                  child: Row(
                    mainAxisAlignment: MainAxisAlignment.spaceBetween,
                    children: [
                      Text(
                        getFormattedDate(DateTime.fromMicrosecondsSinceEpoch(
                            file.creationTime)),
                        style: TextStyle(
                          fontSize: 18,
                          fontWeight: FontWeight.bold,
                        ),
                      ),
                      IconButton(
                        icon: Icon(Icons.share),
                        onPressed: () {
                          share(context, file);
                        },
                      ),
                    ],
                  ),
                )
              ]);
            },
            itemCount: widget.memories.length,
            pagination: SwiperPagination(
                builder: DotSwiperPaginationBuilder(activeColor: Colors.white)),
            loop: false,
          ),
          Center(
            child: AnimatedOpacity(
              opacity: _opacity,
              duration: Duration(seconds: 1),
              child: Text(
                widget.title,
                style: TextStyle(
                  fontSize: 32,
                  fontWeight: FontWeight.bold,
                ),
              ),
            ),
          ),
        ]),
      ),
    );
  }
}