BotZ_app/lib/ui/operations_page.dart

import 'package:flutter/material.dart';
import 'package:logger/logger.dart';
import 'package:shared_preferences/shared_preferences.dart';
import 'dart:async';

import 'drawer.dart';
import '../utils/connection.dart';

var log = Logger();

typedef WhatNext = Future<void> Function();

Card loadingTile(bool loading, Widget subject, WhatNext callback) {
  Widget widgetBody;
  if (loading) {
    widgetBody = CircularProgressIndicator();
  } else {
    widgetBody = subject;
  }
  return Card(
      child: ListTile(title: Center(child: widgetBody), onTap: callback));
}

class OperationsPage extends StatefulWidget {
  OperationsPage({Key key, this.title = "Operations"}) : super(key: key);
  final String title;

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

class _OperationsState extends State<OperationsPage> {
  Connection connection;
  bool connected = false;
  bool checkedIn = false;
  bool _loading = false;

  Future<void> initConnect() async {
    var persistence = await SharedPreferences.getInstance();
    var _username = persistence.getString("username");
    var _password = persistence.getString("password");
    var _baseAddr = Uri.parse(persistence.getString("botZAddress"));
    log.d("user: $_username\npass: $_password\nbaseAddr: $_baseAddr");

    if (_username == null || _password == null || _baseAddr == null) {
      throw Exception("Missing configurations!");
    }

    var _connection = Connection(_username, _password, _baseAddr);
    setState(() {
      connection = _connection;
      connected = connection.isLoggedIn();
    });
  }

  Future<void> login() async {
    log.d("Logging in...");
    setState(() {
      _loading = true;
    });
    await connection.login();
    setState(() {
      connected = connection.isLoggedIn();
      checkedIn = connection.isCheckedIn();
      _loading = false;
    });
  }

  Future<void> logout() async {
    log.d("Logging in...");
    setState(() {
      _loading = true;
    });
    await connection.logout();
    setState(() {
      connected = connection.isLoggedIn();
      checkedIn = connection.isCheckedIn();
      _loading = false;
    });
  }

  Future<void> checkIn() async {
    log.d("Checking in...");
    setState(() {
      _loading = true;
    });
    await connection.checkin();
    setState(() {
      checkedIn = connection.isCheckedIn();
      _loading = false;
    });
  }

  Future<void> checkOut() async {
    log.d("Checking out...");
    setState(() {
      _loading = true;
    });
    await connection.checkout();
    setState(() {
      checkedIn = connection.isCheckedIn();
      _loading = false;
    });
  }

  loginButton() {
    if (_loading) {
      return CircularProgressIndicator();
    } else {
      return Text("Login");
    }
  }

  _loggedOutBody(BuildContext context) => <Widget>[
        loadingTile(
            this._loading,
            Row(children: <Widget>[
              Icon(Icons.arrow_forward_ios),
              Text("Login")
            ]),
            login)
      ];

  // Column(
  // mainAxisAlignment: MainAxisAlignment.spaceEvenly,
  // crossAxisAlignment: CrossAxisAlignment.center,
  // children: <Widget>[
  //   Center(child: Text("You are not logged in")),
  //   RaisedButton(onPressed: login, child: loginButton()),
  // ]);

  Widget checkInOutTile() {
    if (checkedIn) {
      return loadingTile(
          this._loading,
          Row(children: <Widget>[Icon(Icons.arrow_downward), Text("Check out")]),
          checkOut);
    } else {
      return loadingTile(
          this._loading,
          Row(children: <Widget>[Icon(Icons.arrow_upward), Text("Check in")]),
          checkIn);
    }
  }

  _loggedInBody(BuildContext context) => <Widget>[
        checkInOutTile(),
        loadingTile(this._loading,
            Row(children: <Widget>[Icon(Icons.close), Text("Logout")]), logout)
      ];

  _body(BuildContext context) {
    if (connected) {
      return _loggedInBody(context);
    } else {
      return _loggedOutBody(context);
    }
  }

  @override
  void initState() {
    super.initState();
    initConnect();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text(widget.title)),
      body: ListView(padding: EdgeInsets.all(5), children: _body(context)),
      drawer: theDrawer(context),
    );
  }
}