<!-- The <day-range-sk> custom element declaration.

  Allows picking a range of time from the last year.

  Attributes:
    begin - The beginning of the selected time range, given in seconds
       since the Unix epoch.
    end - The end of the selected time range, given in seconds
       since the Unix epoch.

  Events:
    day-range-change - Fired then the selection has stopped changing. Contains
      the begin and end timestamps in the details:

      {
        begin: 1470084997,
        end: 1474184677
      }

  Methods:
    None.
-->

<link rel="import" href="/res/imp/rangesel.html" />

<dom-module id="day-range-sk">
  <style>
    :host {
      position: relative;
    }

    range-sel-sk {
      display: block;
      margin-bottom: 2em;
    }

    #hbegin,
    #hend {
     display: inline-block;
     margin: 0.5em 0 0.5em 0.5em;
     padding: 0.4em;
     border: solid 1px lightgray;
    }

    #ticks {
      position: absolute;
      width: 600px;
      height: 40px;
      top: 30px;
      left: 10px;
    }

    .tick {
      position: absolute;
      border-left: solid gray 1px;
      padding: 16px 0 0 4px;
      font-size: 10px;
    }
  </style>
  <template>
    <range-sel-sk
      begin="[[_pct_begin]]"
      end="[[_pct_end]]"
      on-range-change="_rangeChange"
      on-range-change-end="_rangeChangeEnd"
      ></range-sel-sk>
    <div id=ticks>
      <div id=m0  class=tick></div>
      <div id=m1  class=tick></div>
      <div id=m2  class=tick></div>
      <div id=m3  class=tick></div>
      <div id=m4  class=tick></div>
      <div id=m5  class=tick></div>
      <div id=m6  class=tick></div>
      <div id=m7  class=tick></div>
      <div id=m8  class=tick></div>
      <div id=m9  class=tick></div>
      <div id=m10 class=tick></div>
      <div id=m11 class=tick></div>
    </div>
    <span id=hbegin></span>
    <span id=hend></span>
  </template>
</dom-module>

<script>
  (function () {
    var MONTHS = [
      "Jan",
      "Feb",
      "Mar",
      "Apr",
      "May",
      "Jun",
      "Jul",
      "Aug",
      "Sep",
      "Oct",
      "Nov",
      "Dec",
      ];

    Polymer({
      is: "day-range-sk",

      properties: {
        begin: {
          type: Number,
          value: 0,
          reflectToAttribute: true,
          observer: "_beginChange",
        },
        end: {
          type: Number,
          value: 0,
          reflectToAttribute: true,
          observer: "_endChange",
        },
        now: {
          type: Date,
          value: Date.now(),
        },
        _pct_begin: {
          type: Number,
          value: 0,
        },
        _pct_end: {
          type: Number,
          value: 0,
        },
      },

      ready: function() {
        this._calcTicks();
      },

      _ts2Percent: function(ts) {
        var t = new Date(ts*1000);
        var diff = new Date(this.now - t);
        return (1.0 - diff/(365*24*60*60*1000)) * 100;
      },

      _percent2Ts: function(p) {
        return Math.floor((new Date(this.now - (1.0 - p/100)*(365*24*60*60*1000)))/1000);
      },

      _beginChange: function() {
        this.set("_pct_begin", this._ts2Percent(this.begin));
        this._calcTicks();
        this.$.hbegin.textContent = this._display(this._ts2Percent(this.begin));
      },

      _endChange: function() {
        this.set("_pct_end", this._ts2Percent(this.end));
        this._calcTicks();
        this.$.hend.textContent = this._display(this._ts2Percent(this.end));
      },

      _rangeChange: function(e) {
        this.$.hbegin.textContent = this._display(e.detail.begin);
        this.$.hend.textContent = this._display(e.detail.end);
      },

      _rangeChangeEnd: function(e) {
        this.set("begin", this._percent2Ts(e.detail.begin));
        this.set("end", this._percent2Ts(e.detail.end));
        var msg = {
          begin: this.begin,
          end: this.end,
        };
        this.fire("day-range-change", msg);
      },

      _display: function(p) {
        var ts = this._percent2Ts(p);
        // Convert ts to human friendly string.
        var d = new Date(ts*1000);
        return MONTHS[d.getMonth()] + " " + d.getDate();
      },

      _calcTicks: function() {
        var d = new Date();
        d.setDate(1);
        var month = d.getMonth();
        for (var i = 0; i < 12; i++) {
          var ele = $$$('#m' + i, this);
          ele.textContent = MONTHS[d.getMonth()];
          ele.style.left = Math.floor(600*this._ts2Percent(d.valueOf()/1000)/100) - 2 + "px";
          if (month == 0) {
            d.setFullYear(d.getFullYear()-1);
            month = 11;
            d.setMonth(month);
          } else {
            month--;
            d.setMonth(month);
          }
        }
      },

    });
  })();
</script>