[SC] [DBAPI] main.dart

import 'package:flutter/material.dart';
import 'package:flutter/widgets.dart';
import 'controls/apiClient.dart';
import 'controls/databaseClient.dart';
import 'models/dog.dart';

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      theme: ThemeData(
        primarySwatch: Colors.cyan,
      ),
      home: DogPage(),
    );
  }
}

class DogPage extends StatefulWidget {
  @override
  _DogPageState createState() => _DogPageState();
}

class _DogPageState extends State<DogPage> {
  final GlobalKey<FormState> _formStateKey = GlobalKey<FormState>();

  final _scaffoldKey = GlobalKey<ScaffoldState>();

  Future<List<Dog>> dogs;

  List<Dog> dogsFromApi;
  List<Dog> dogsFromDb;

  String _dogId;
  String _dogName;
  int _dogAge;

  bool isUpdate = false;

  String dogIdForUpdate;

  DatabaseClient db;

  ApiClient api;

  final _dogIdController = TextEditingController();
  final _dogNameController = TextEditingController();
  final _dogAgeController = TextEditingController();

  @override
  void initState() {
    super.initState();
    db = DatabaseClient();
    api = ApiClient();
    openDatabase();
  }

  openDatabase() async {
    await db.open();
    await refreshDogList();
  }

  refreshDogList() {
    setState(() {
      dogs = db.getDogs();
    });
  }

  Future<Dog> uploadOnApi(dog) async {
    try {
      Dog newDog = await api.insertDog(dog);

      final snackBar = SnackBar(
        content: Text('Dados enviados com sucesso para a API!'),
        duration: Duration(milliseconds: 500),
        backgroundColor: Colors.green,
      );

      _scaffoldKey.currentState.showSnackBar(snackBar);

      return newDog;
    }
    catch (error) {
      final snackBar = SnackBar(
        content: Text('Erro ao enviar dado para a API!'),
        duration: Duration(milliseconds: 500),
        backgroundColor: Colors.red,
      );
      _scaffoldKey.currentState.showSnackBar(snackBar);

      return null;
    }
  }

  uploadOnDb(dog) async {
    try {
      await db.insertDog(dog);
      final snackBar = SnackBar(
        content: Text('Dados enviados com sucesso para a BD!'),
        duration: Duration(milliseconds: 500),
        backgroundColor: Colors.green,
      );
      _scaffoldKey.currentState.showSnackBar(snackBar);
    }
    catch (error) {
      final snackBar = SnackBar(
        content: Text('Erro ao enviar dado para o BD!'),
        duration: Duration(milliseconds: 500),
        backgroundColor: Colors.red,
      );
      _scaffoldKey.currentState.showSnackBar(snackBar);
    }
  }

  deleteOnApi(Dog dog) async {
    try {
      await api.deleteDog(dog.id);
      final snackBar = SnackBar(
        content: Text('Dado removido com sucesso da API!'),
        duration: Duration(milliseconds: 500),
        backgroundColor: Colors.green,
      );
      _scaffoldKey.currentState.showSnackBar(snackBar);
    }
    catch (error) {
      final snackBar = SnackBar(
        content: Text('Erro ao remover dado da API!'),
        duration: Duration(milliseconds: 500),
        backgroundColor: Colors.red,
      );
      _scaffoldKey.currentState.showSnackBar(snackBar);
    }
  }

  deleteOnDb(Dog dog) async {
    try {
      await db.deleteDog(dog.id);
      final snackBar = SnackBar(
        content: Text('Dado removido com sucesso do BD!'),
        duration: Duration(milliseconds: 500),
        backgroundColor: Colors.green,
      );
      _scaffoldKey.currentState.showSnackBar(snackBar);
    }
    catch (error) {
      final snackBar = SnackBar(
        content: Text('Erro ao remover dado do BD!'),
        duration: Duration(milliseconds: 500),
        backgroundColor: Colors.red,
      );
      _scaffoldKey.currentState.showSnackBar(snackBar);
    }
  }

  Future<Dog> updateOnApi(Dog dog) async {
    try {
      Dog newDog = await api.updateDog(dog);

      final snackBar = SnackBar(
        content: Text('Dado atualizado com sucesso da API!'),
        duration: Duration(milliseconds: 500),
        backgroundColor: Colors.green,
      );
      _scaffoldKey.currentState.showSnackBar(snackBar);

      return newDog;
    }
    catch (error) {
      final snackBar = SnackBar(
        content: Text('Erro ao atualizar dado na API!'),
        duration: Duration(milliseconds: 500),
        backgroundColor: Colors.red,
      );
      _scaffoldKey.currentState.showSnackBar(snackBar);

      return null;
    }
  }

  updateOnDb(Dog dog) async {
    try {
      await db.updateDog(dog);
      final snackBar = SnackBar(
        content: Text('Dado atualizado com sucesso do BD!'),
        duration: Duration(milliseconds: 500),
        backgroundColor: Colors.green,
      );
      _scaffoldKey.currentState.showSnackBar(snackBar);
    }
    catch (error) {
      final snackBar = SnackBar(
        content: Text('Erro ao atualizar dado no BD!'),
        duration: Duration(milliseconds: 500),
        backgroundColor: Colors.red,
      );
      _scaffoldKey.currentState.showSnackBar(snackBar);
    }
  }

  downloadFromApi() async {
    var errorDownload = false;

    try {
      dogsFromApi = await api.getDogs();

      final snackBar = SnackBar(
        content: Text('Dados lidos com sucesso na API!'),
        duration: Duration(milliseconds: 500),
        backgroundColor: Colors.green,
      );
      _scaffoldKey.currentState.showSnackBar(snackBar);
    }
    catch (erro) {
      errorDownload = true;

      final snackBar = SnackBar(
        content: Text('Erro ao comunicar com a API!'),
        duration: Duration(milliseconds: 500),
        backgroundColor: Colors.red,
      );
      _scaffoldKey.currentState.showSnackBar(snackBar);
    }

    if (errorDownload == false) {
      await db.deleteAllDogs();
      await db.insertDogs(dogsFromApi);
      refreshDogList();

      final snackBar = SnackBar(
        content: Text('Dados armazenados com sucesso no BD!'),
        duration: Duration(milliseconds: 500),
        backgroundColor: Colors.green,
      );
      _scaffoldKey.currentState.showSnackBar(snackBar);
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      key: _scaffoldKey,
      appBar: AppBar(title: Text('App Dog'), actions: <Widget>[
        Padding(
            padding: EdgeInsets.only(right: 20.0),
            child: GestureDetector(
              onTap: () {
                downloadFromApi();
              },
              child: Icon(Icons.cloud_download),
            )),
      ]),

      body: Column(
        children: <Widget>[
          Form(
            key: _formStateKey,
            autovalidate: true,
            child: Column(
              children: <Widget>[
                Padding(
                  padding: EdgeInsets.only(left: 10, right: 10, bottom: 10),
                  child: TextFormField(
                    enabled: false,
                    onSaved: (value) {
                      _dogId = value;
                    },
                    controller: _dogIdController,
                    keyboardType: TextInputType.number,
                    decoration: InputDecoration(
                        disabledBorder: new UnderlineInputBorder(
                            borderSide: new BorderSide(
                                color: Colors.grey,
                                width: 2,
                                style: BorderStyle.solid)),
                        labelText: "Id do cachorro",
                        icon: Icon(
                          Icons.vpn_key,
                          color: Colors.grey,
                        ),
                        fillColor: Colors.white,
                        labelStyle: TextStyle(
                          color: Colors.grey,
                        )),
                  ),
                ),

                Padding(
                  padding: EdgeInsets.only(left: 10, right: 10, bottom: 10),
                  child: TextFormField(
                    validator: (value) {
                      if (value.isEmpty) {
                        return 'Por favor insira o nome do cachorro';
                      }
                      if (value.trim() == "")
                        return "Somente espaço não é válido!";
                      return null;
                    },
                    onSaved: (value) {
                      _dogName = value;
                    },
                    controller: _dogNameController,
                    decoration: InputDecoration(
                        focusedBorder: new UnderlineInputBorder(
                            borderSide: new BorderSide(
                                color: Colors.cyan,
                                width: 2,
                                style: BorderStyle.solid)),
                        labelText: "Nome do cachorro",
                        icon: Icon(
                          Icons.pets,
                          color: Colors.cyan,
                        ),
                        fillColor: Colors.white,
                        labelStyle: TextStyle(
                          color: Colors.cyan,
                        )),
                  ),
                ),

                Padding(
                  padding: EdgeInsets.only(left: 10, right: 10, bottom: 10),
                  child: TextFormField(
                    validator: (value) {
                      if (value.isEmpty) {
                        return 'Por favor insira a idade do cachorro';
                      }
                      if (value.trim() == "")
                        return "Somente espaço não é válido!";
                      return null;
                    },
                    onSaved: (value) {
                      _dogAge = int.parse(value);
                    },
                    controller: _dogAgeController,
                    keyboardType: TextInputType.number,
                    decoration: InputDecoration(
                        focusedBorder: new UnderlineInputBorder(
                            borderSide: new BorderSide(
                                color: Colors.cyan,
                                width: 2,
                                style: BorderStyle.solid)),
                        labelText: "Idade do cachorro",
                        icon: Icon(
                          Icons.calendar_today,
                          color: Colors.cyan,
                        ),
                        fillColor: Colors.white,
                        labelStyle: TextStyle(
                          color: Colors.cyan,
                        )),
                  ),
                ),
              ],
            ),
          ),

          Row(
            mainAxisAlignment: MainAxisAlignment.center,
            children: <Widget>[
              RaisedButton(
                color: Colors.cyan,
                child: Text(
                  (isUpdate ? 'ATUALIZAR' : 'ADICIONAR'),
                  style: TextStyle(color: Colors.white),
                ),
                onPressed: () async {
                  FocusScope.of(context).requestFocus(new FocusNode());

                  if (isUpdate) {
                    if (_formStateKey.currentState.validate()) {
                      _formStateKey.currentState.save();
                      try {
                        Dog dog = Dog(
                            id: dogIdForUpdate, name: _dogName, age: _dogAge);

                        await updateOnDb(await updateOnApi(dog));
                        refreshDogList();
                        setState(() {
                          isUpdate = false;
                        });
                      }
                      catch (error) {
                        print(error);
                        final snackBar = SnackBar(
                          content: Text('Erro ao comunicar com a API!'),
                          duration: Duration(milliseconds: 500),
                          backgroundColor: Colors.red,
                        );
                        _scaffoldKey.currentState.showSnackBar(snackBar);
                      }
                    }
                  }
                  else {
                    if (_formStateKey.currentState.validate()) {
                      _formStateKey.currentState.save();
                      try {
                        Dog dog = Dog(id: _dogId, name: _dogName, age: _dogAge);
                        await uploadOnDb(await uploadOnApi(dog));

                        refreshDogList();
                      }
                      catch (error) {
                        final snackBar = SnackBar(
                          content: Text('Erro ao comunicar com a API!'),
                          duration: Duration(milliseconds: 500),
                          backgroundColor: Colors.red,
                        );
                        _scaffoldKey.currentState.showSnackBar(snackBar);
                      }
                    }
                  }
                  _dogIdController.text = '';
                  _dogNameController.text = '';
                  _dogAgeController.text = '';
                },
              ),
              Padding(
                padding: EdgeInsets.all(10),
              ),
              RaisedButton(
                color: Colors.red,
                child: Text(
                  (isUpdate ? 'CANCELAR ATUALIZAÇÃO' : 'LIMPAR'),
                  style: TextStyle(color: Colors.white),
                ),
                onPressed: () {
                  _dogIdController.text = '';
                  _dogNameController.text = '';
                  _dogAgeController.text = '';

                  setState(() {
                    isUpdate = false;
                    dogIdForUpdate = null;
                  });
                },
              ),
            ],
          ),
          const Divider(
            height: 20.0,
          ),
          Expanded(
            child: FutureBuilder(
              future: dogs,
              builder: (context, snapshot) {
                print(snapshot.connectionState);
                if (snapshot.data == null || snapshot.data.length == 0) {
                  return Text('Sem dados para exibir');
                }
                else if (snapshot.hasData) {
                  return generateList(snapshot.data);
                }
                return CircularProgressIndicator();
              },
            ),
          ),
        ],
      ),
    );
  }

  SingleChildScrollView generateList(List<Dog> dogs) {
    return SingleChildScrollView(
      scrollDirection: Axis.vertical,
      child: SingleChildScrollView(
        scrollDirection: Axis.horizontal,
        child: DataTable(
          columns: [
            DataColumn(
              label: Text('ID', style: TextStyle(fontStyle: FontStyle.italic)),
            ),
            DataColumn(
              label:
                  Text('NOME', style: TextStyle(fontStyle: FontStyle.italic)),
            ),
            DataColumn(
              label:
                  Text('IDADE', style: TextStyle(fontStyle: FontStyle.italic)),
            ),
            DataColumn(
              label: Text('DELETAR',
                  style: TextStyle(fontStyle: FontStyle.italic)),
            )
          ],
          rows: dogs
              .map(
                (dog) => DataRow(
                  cells: [
                    DataCell(
                      Text(dog.id.toString()),
                      onTap: () {
                        setState(() {
                          isUpdate = true;
                          dogIdForUpdate = dog.id;
                        });
                        _dogIdController.text = dog.id.toString();
                        _dogNameController.text = dog.name;
                        _dogAgeController.text = dog.age.toString();
                      },
                    ),
                    DataCell(
                      Text(dog.name),
                      onTap: () {
                        setState(() {
                          isUpdate = true;
                          dogIdForUpdate = dog.id;
                        });
                        _dogIdController.text = dog.id.toString();
                        _dogNameController.text = dog.name;
                        _dogAgeController.text = dog.age.toString();
                      },
                    ),
                    DataCell(
                      Text(dog.age.toString()),
                      onTap: () {
                        setState(() {
                          isUpdate = true;
                          dogIdForUpdate = dog.id;
                        });
                        _dogIdController.text = dog.id.toString();
                        _dogNameController.text = dog.name;
                        _dogAgeController.text = dog.age.toString();
                      },
                    ),
                    DataCell(
                      IconButton(
                        icon: Icon(Icons.delete),
                        onPressed: () {
                          try {
                            deleteOnApi(dog);
                            deleteOnDb(dog);
                            refreshDogList();
                          }
                          catch (error) {
                            final snackBar = SnackBar(
                              content: Text('Erro ao comunicar com a API!'),
                              duration: Duration(milliseconds: 500),
                              backgroundColor: Colors.red,
                            );
                            _scaffoldKey.currentState.showSnackBar(snackBar);
                          }
                        },
                      ),
                    ),
                  ],
                ),
              )
              .toList(),
        ),
      ),
    );
  }
}