meincantor-app/lib/news.dart

// GCG.MeinCantor - Die Schulplattform für Cantorianer.
// Copyright (C) 2021-2022 Georg-Cantor-Gymnasium Halle (Saale)

// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published
// by the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.

// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <https://www.gnu.org/licenses/>.

import 'dart:convert';
import 'package:meincantor/networking.dart';
import 'package:flutter/material.dart';
import 'package:flutter_markdown/flutter_markdown.dart';
import 'package:http/http.dart' as http;
import 'package:material_design_icons_flutter/material_design_icons_flutter.dart';
import 'package:shared_preferences/shared_preferences.dart';

Future<List> getNewsRead() async {
  SharedPreferences prefs = await SharedPreferences.getInstance();
  String? newsReadString = prefs.getString("newsRead");
  List<dynamic> newsRead;
  if (newsReadString == null ||
      (jsonDecode(newsReadString) as List<dynamic>).isEmpty) {
    newsRead = [];
  } else {
    newsRead = jsonDecode(newsReadString) as List<dynamic>;
  }
  return newsRead;
}

class News extends StatefulWidget {
  const News({Key? key}) : super(key: key);

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

class _NewsState extends State<News> {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
        appBar: AppBar(
          title: const Text("Aktuelles"),
          centerTitle: true,
        ),
        body: LayoutBuilder(builder: (context, constraints) {
          double widgetWidth = constraints.maxWidth;

          int factor;

          if (widgetWidth <= 600) {
            factor = 1;
          } else if (widgetWidth <= 1400) {
            factor = 2;
          } else if (widgetWidth <= 2000) {
            factor = 3;
          } else {
            factor = 1;
          }

          return Center(
            heightFactor: 1,
            child: Container(
              constraints: BoxConstraints(
                maxWidth: MediaQuery.of(context).size.width / factor,
              ),
              child: FutureBuilder<http.Response>(
                future: getNews(),
                builder: (context, snapshot) {
                  if (snapshot.hasData) {
                    int statusCode = snapshot.data!.statusCode;
                    if (statusCode == 200) {
                      String data = utf8.decode(snapshot.data!.bodyBytes);
                      List articles = jsonDecode(data)["data"];
                      List<Widget> articleTiles = [];
                      for (var element in articles) {
                        int id = element["id"];
                        element = element["attributes"];
                        Color color = Colors.white70;
                        Widget card = FutureBuilder(
                          future: getNewsRead(),
                          builder: (context, snapshot) {
                            if (snapshot.hasData) {
                              List<dynamic> readList =
                                  snapshot.data! as List<dynamic>;
                              if (!readList.contains(id)) {
                                return GestureDetector(
                                  onTap: () async {
                                    SharedPreferences prefs =
                                        await SharedPreferences.getInstance();
                                    Navigator.push(
                                      context,
                                      MaterialPageRoute(
                                          builder: (context) =>
                                              Article.fromData(
                                                      element["title"],
                                                      element["content"],
                                                      element["author"],
                                                      element["publish_date"])
                                                  .widget),
                                    );
                                    readList.add(id);
                                    prefs.setString(
                                        "newsRead", jsonEncode(readList));
                                    setState(() {
                                      color = Colors.transparent;
                                    });
                                  },
                                  child: Card(
                                      color: color,
                                      child: Padding(
                                          padding: const EdgeInsets.fromLTRB(
                                              10, 10, 10, 10),
                                          child: FutureBuilder(
                                            future: Future.delayed(
                                                const Duration(seconds: 0)),
                                            builder: (context, snapshot) {
                                              if (element["summary"] != null &&
                                                  (element["summary"] as String)
                                                      .isNotEmpty) {
                                                return ListTile(
                                                  title: Text(element["title"],
                                                      style: const TextStyle(
                                                          fontWeight:
                                                              FontWeight.bold)),
                                                  subtitle: Text(
                                                    element["summary"],
                                                    overflow:
                                                        TextOverflow.ellipsis,
                                                    maxLines: 2,
                                                    softWrap: true,
                                                  ),
                                                  trailing: Text(
                                                      "${DateTime.parse(element["publish_date"]).day.toString()}.${DateTime.parse(element["publish_date"]).month.toString()}.${DateTime.parse(element["publish_date"]).year.toString()}"),
                                                );
                                              } else {
                                                return ListTile(
                                                  title: Text(element["title"],
                                                      style: const TextStyle(
                                                          fontWeight:
                                                              FontWeight.bold)),
                                                  trailing: Text(
                                                      "${DateTime.parse(element["publish_date"]).day.toString()}.${DateTime.parse(element["publish_date"]).month.toString()}.${DateTime.parse(element["publish_date"]).year.toString()}"),
                                                );
                                              }
                                            },
                                          )),
                                      shape: RoundedRectangleBorder(
                                        borderRadius: BorderRadius.circular(15),
                                      )),
                                );
                              } else {
                                return GestureDetector(
                                  onTap: () {
                                    Navigator.push(
                                      context,
                                      MaterialPageRoute(
                                          builder: (context) =>
                                              Article.fromData(
                                                      element["title"],
                                                      element["content"],
                                                      element["author"],
                                                      element["publish_date"])
                                                  .widget),
                                    );
                                  },
                                  child: Card(
                                      child: Padding(
                                          padding: const EdgeInsets.fromLTRB(
                                              10, 10, 10, 10),
                                          child: FutureBuilder(
                                            future: Future.delayed(
                                                const Duration(seconds: 0)),
                                            builder: (context, snapshot) {
                                              if (element["summary"] != null &&
                                                  (element["summary"] as String)
                                                      .isNotEmpty) {
                                                return ListTile(
                                                  title: Text(element["title"],
                                                      style: const TextStyle(
                                                          fontWeight:
                                                              FontWeight.bold)),
                                                  subtitle: Text(
                                                    element["summary"],
                                                    overflow:
                                                        TextOverflow.ellipsis,
                                                    maxLines: 2,
                                                    softWrap: true,
                                                  ),
                                                  trailing: Text(
                                                      "${DateTime.parse(element["publish_date"]).day.toString()}.${DateTime.parse(element["publish_date"]).month.toString()}.${DateTime.parse(element["publish_date"]).year.toString()}"),
                                                );
                                              } else {
                                                return ListTile(
                                                  title: Text(element["title"],
                                                      style: const TextStyle(
                                                          fontWeight:
                                                              FontWeight.bold)),
                                                  trailing: Text(
                                                      "${DateTime.parse(element["publish_date"]).day.toString()}.${DateTime.parse(element["publish_date"]).month.toString()}.${DateTime.parse(element["publish_date"]).year.toString()}"),
                                                );
                                              }
                                            },
                                          )),
                                      shape: RoundedRectangleBorder(
                                        borderRadius: BorderRadius.circular(15),
                                      )),
                                );
                              }
                            } else {
                              return const LinearProgressIndicator();
                            }
                          },
                        );
                        articleTiles.add(card);
                      }
                      return ListView(
                        children: articleTiles.reversed.toList(),
                      );
                    } else {
                      return (const Center(
                          child:
                              Text("Uups... Irgendwas ist schief gelaufen")));
                    }
                  } else {
                    return (const Center(child: CircularProgressIndicator()));
                  }
                },
              ),
            ),
          );
        }));
  }
}

class Article {
  Widget widget;
  //const Article({Key? key}) : super(key: key);
  Article({required this.widget});
  factory Article.fromData(
      String title, String content, String author, String publishDate) {
    return Article(
        widget: Scaffold(
            appBar: AppBar(
              title: SingleChildScrollView(
                scrollDirection: Axis.vertical,
                child: SingleChildScrollView(
                    scrollDirection: Axis.horizontal, child: Text(title)),
              ),
              centerTitle: true,
            ),
            body: ListView(
              padding: const EdgeInsets.fromLTRB(15, 15, 15, 15),
              children: [
                ListTile(
                  leading: const Icon(MdiIcons.accountOutline),
                  title: Text(author),
                ),
                ListTile(
                  leading: const Icon(MdiIcons.calendarOutline),
                  title: Text(
                      "${DateTime.parse(publishDate).day.toString()}.${DateTime.parse(publishDate).month.toString()}.${DateTime.parse(publishDate).year.toString()}"),
                ),
                MarkdownBody(data: content)
              ],
            )));
  }
}