<!DOCTYPE html>
<!--
Copyright (c) 2013 The Chromium Authors. All rights reserved.
Use of this source code is governed by a BSD-style license that can be
found in the LICENSE file.
-->

<link rel="import" href="/ui/tracks/chart_axis.html">
<link rel="import" href="/ui/tracks/chart_point.html">
<link rel="import" href="/ui/tracks/chart_series.html">
<link rel="import" href="/ui/tracks/chart_track.html">
<link rel="import" href="/ui/base/ui.html">

<script>
'use strict';

tr.exportTo('tr.ui.tracks', function() {

  /**
   * A track that displays a Counter object.
   * @constructor
   * @extends {ChartTrack}
   */
  var CounterTrack = tr.ui.b.define('counter-track', tr.ui.tracks.ChartTrack);

  CounterTrack.prototype = {
    __proto__: tr.ui.tracks.ChartTrack.prototype,

    decorate: function(viewport) {
      tr.ui.tracks.ChartTrack.prototype.decorate.call(this, viewport);
      this.classList.add('counter-track');
    },

    get counter() {
      return this.chart;
    },

    set counter(counter) {
      this.heading = counter.name + ': ';
      this.series = CounterTrack.buildChartSeriesFromCounter(counter);
      this.autoSetAllAxes({expandMax: true});
    },

    getModelEventFromItem: function(chartValue) {
      return chartValue;
    }
  };

  CounterTrack.buildChartSeriesFromCounter = function(counter) {
    var numSeries = counter.series.length;
    var totals = counter.totals;

    // Create one common axis for all series.
    var chartAxis = new tr.ui.tracks.ChartAxis(0, undefined);

    // Build one chart series for each counter series.
    var chartSeries = counter.series.map(function(series, seriesIndex) {
      var chartPoints = series.samples.map(function(sample, sampleIndex) {
        var total = totals[sampleIndex * numSeries + seriesIndex];
        return new tr.ui.tracks.ChartPoint(sample, sample.timestamp, total);
      });
      var renderingConfig = {
        chartType: tr.ui.tracks.ChartSeriesType.AREA,
        colorId: series.color
      };
      return new tr.ui.tracks.ChartSeries(
          chartPoints, chartAxis, renderingConfig);
    });

    // Show the first series (with the smallest cumulative value) at the top.
    chartSeries.reverse();

    return chartSeries;
  };

  return {
    CounterTrack: CounterTrack
  };
});
</script>