homeworkreactjs/hw2/weatherGenerator/files/js/index.js

var selects = document.querySelector('.selects');
var weatherDiv = document.querySelector('.weather');

function get(url){
  return new Promise(function(resolve,reject){
    var xhr = new XMLHttpRequest();
    xhr.open('GET',url,true);
    xhr.onload = function(){
      if(xhr.status == 200){
        resolve(JSON.parse(xhr.responseText));
      }
      else{
        reject(xhr.statusText);
      }
    }
    xhr.onerror = function(){
      reject('not found');
    }
    xhr.send();
  });
}
function show(obj){
  var weather = obj.query.results.channel.item.description;
  var resWeather = weather.replace(/href|CDATA|[\!]|[\[]|[\]]/g,"");
  var resWeather2 = resWeather.slice(1,resWeather.length - 1);
  var resWeather3 = resWeather2.replace(/Full Forecast at Yahoo Weather/g,"");
  var resWeather4 = resWeather3.slice(0,resWeather3.length - 28);
  weatherDiv.innerHTML = resWeather4;
}

function* myGenerator(){
  var object = yield get('https://raw.githubusercontent.com/David-Haim/CountriesToCitiesJSON/master/countriesToCities.json');
  var keys = Object.keys(object);
  var select = document.createElement("select");
  for (var i = 0; i < keys.length; i++) {
      var option = document.createElement("option");
      option.innerHTML = keys[i];
      option.value = keys[i];
      select.appendChild(option);
  }
  select.onchange = function(){
    var g1 = select1();
    g1.next();
  }
   function* select1(e){
      var select = document.createElement("select");
      for (var i = 0; i < object[this.value].length; i++) {
          var option = document.createElement("option")
          option.innerHTML = object[this.value][i];
          select.appendChild(option);
      }
      if(selects.children.length > 1){
          selects.replaceChild(select, document.getElementById("main").nextElementSibling);
      }
      else
          selects.appendChild(select);
          debugger;
        var obj = yield get("https://query.yahooapis.com/v1/public/yql?" + 'q=' + encodeURIComponent("select * from weather.forecast where woeid in (select woeid from geo.places(1) where text=\'" + select.value + "\') and u='c'") + '&format=json');
        show(obj);
      select2.onchange = function(){
        var g2 = select1();
        g2.next();
      }
      function* select2(){
        var obj = yield get("https://query.yahooapis.com/v1/public/yql?" + 'q=' + encodeURIComponent("select * from weather.forecast where woeid in (select woeid from geo.places(1) where text=\'" + this.value + "\') and u='c'") + '&format=json');
        show(obj);
      }
  }
  selects.appendChild(select);
  select.id = "main"
}

function run(g){
  var iter = g();
  function next(result){
      console.log(iter.next(result))
      let {value, done} = iter.next(result)
      if (typeof value === 'object' && 'then' in value){
          value.then(next,(e) => iter.throw(e))
      }
  }
  next();
}
run(myGenerator);