function update_graph(g) {
	  var payload = {i: $('index').value,
		             s: $('series').value,
		             t: $('tenor').value,
                     w: $('what').value};
	  query("_data_indices",
		      payload,
		      function(data){
              data = JSON.parse(data);
		          var newdata = data["data"].map(function(e){
			            f = e.slice(1);
			            f.unshift(new Date(e[0]));
			            return f});
		          g.updateOptions({'file': newdata, 'labels': data['labels']});
		      });
};

document.addEventListener("DOMContentLoaded", function() {
    var g = new Dygraph($("graph"),
		                    [], // path to CSV file
		                    { labels: [],
		                      title: "Index quotes",
		                      showRoller: true,
		                      legend: "always"});
    ["index", "series", "tenor", "what"].forEach(function(id) {
        $(id).addEventListener('change', function(){
            update_graph(g)});
    })
    update_graph(g);
});