import 'dart:async';
import 'dart:convert';

import 'package:flutter/material.dart';
import 'package:http/http.dart' as http;

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return new MaterialApp(
      title: 'Flutter Demo',
      theme: new ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: new MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);

  final String title;

  @override
  _MyHomePageState createState() => new _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  Widget image;

  Future<String> getImageUrlFromSite() async {
    http.Response res = await http.get(
        "https://api.unsplash.com/photos/random?client_id=1bf67fa81b7d834ac542c7d80ba7f724858d870515e63bf8df91eae3cb022a97");
    String jsonString = res.body;
    dynamic jsonStruct = json.decode(jsonString);
    if (jsonStruct is Map) {
      Map<String, dynamic> data = jsonStruct;
      if (data.containsKey("urls") && data["urls"].containsKey("regular")) return data["urls"]["regular"];
    }
    return null;
  }

  void reMakeCounter() async {
    getImageUrlFromSite().then((String urlFromSite) {
      setState(() {
        image = new Image.network(urlFromSite);
      });
    });
  }

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

    reMakeCounter();
  }

  @override
  Widget build(BuildContext context) {
    Column imageColumn = new Column(
      mainAxisAlignment: MainAxisAlignment.center,
      children: <Widget>[
        new Text(
          'Awaiting for image...',
        ),
      ],
    );
    if (image != null) {
      imageColumn.children.removeLast();
      imageColumn.children.add(image);
    }
    return new Scaffold(
      appBar: new AppBar(
        title: new Text(widget.title),
      ),
      body: new Center(
        child: imageColumn,
      ),
    );
  }
}