Временная шкала диаграммы Google с различными моментами в строке

google.charts.load('current', {
  packages:['timeline']
}).then(function () {
  var container = document.getElementById('chart_div');
  var chart = new google.visualization.Timeline(container);
  var dataTable = new google.visualization.DataTable();
  dataTable.addColumn({type: 'string', id: 'Row'});
  dataTable.addColumn({type: 'string', id: 'Bar'});
  dataTable.addColumn({type: 'date', id: 'Start'});
  dataTable.addColumn({type: 'date', id: 'End'});
  var currentYear = (new Date()).getFullYear();
  dataTable.addRows([
    ['Row 1', 'A-1', new Date(currentYear, 0, 1), new Date(currentYear, 2, 31)],
    ['Row 1', 'A-2', new Date(currentYear, 3, 1), new Date(currentYear, 5, 30)],
    ['Row 2', 'B-1', new Date(currentYear, 6, 1), new Date(currentYear, 8, 31)],
    ['Row 2', 'B-2', new Date(currentYear, 9, 1), new Date(currentYear, 11, 31)]
  ]);
  var dataTableGroup = google.visualization.data.group(dataTable, [0]);
  var dateRangeStart = dataTable.getColumnRange(2);
  var dateRangeEnd = dataTable.getColumnRange(3);
  var formatDate = new google.visualization.DateFormat({
    pattern: 'MM/dd/yyyy'
  });
  var rowHeight = 44;
  var options = {
    height: (dataTableGroup.getNumberOfRows() * rowHeight) + rowHeight
  };
  
  function drawChart() {
    chart.draw(dataTable, options);
  }

  function addMarker(markerDate, row, label) {
    var baseline;
    var baselineBounds;
    var chartElements;
    var markerLabel;
    var markerLine;
    var markerSpan;
    var svg;
    var timeline;
    var timelineRect;
    var timelineUnit;
    var timelineWidth;
    var timespan;

    baseline = null;
    timeline = null;
    svg = null;
    markerLabel = null;
    chartElements = container.getElementsByTagName('svg');
    if (chartElements.length > 0) {
      svg = chartElements[0];
    }
    chartElements = container.getElementsByTagName('rect');
    if (chartElements.length > 0) {
      var rowIndex = 0;
      Array.prototype.forEach.call(chartElements, function(rect) {
        switch (rect.getAttribute('fill')) {
          case 'none':
          case '#ffffff':
          case '#e6e6e6':
            // ignore
            break;

          default:
            console.log(rowIndex, row, (rowIndex === row));
            if (rowIndex === row) {
              timelineRect = rect;
              console.log(timelineRect);
            }
            rowIndex++;
        }
      });
      timeline = chartElements[0];
    }
    chartElements = container.getElementsByTagName('path');
    if (chartElements.length > 0) {
      baseline = chartElements[0];
    }
    chartElements = container.getElementsByTagName('text');
    if (chartElements.length > 0) {
      markerLabel = chartElements[0].cloneNode(true);
    }
    if ((svg === null) || (timeline === null) || (timelineRect === null) || (baseline === null) || (markerLabel === null) ||
        (markerDate.getTime() < dateRangeStart.min.getTime()) ||
        (markerDate.getTime() > dateRangeEnd.max.getTime())) {
      return;
    }

    // calculate placement
    timelineWidth = parseFloat(timeline.getAttribute('width'));
    baselineBounds = baseline.getBBox();
    timespan = dateRangeEnd.max.getTime() - dateRangeStart.min.getTime();
    timelineUnit = (timelineWidth - baselineBounds.x) / timespan;
    markerSpan = markerDate.getTime() - dateRangeStart.min.getTime();

    // add label
    svg.appendChild(markerLabel);
    markerLabel.setAttribute('text-anchor', 'start');
    markerLabel.setAttribute('fill', '#000000');
    markerLabel.setAttribute('y', parseFloat(timelineRect.getAttribute('y')) + parseFloat(markerLabel.getAttribute('font-size')));
    markerLabel.setAttribute('x', (baselineBounds.x + (timelineUnit * markerSpan) + 4));
    markerLabel.textContent = label;

    // add line
    markerLine = timeline.cloneNode(true);
    markerLine.setAttribute('y', timelineRect.getAttribute('y'));
    markerLine.setAttribute('x', (baselineBounds.x + (timelineUnit * markerSpan)));
    markerLine.setAttribute('height', timelineRect.getAttribute('height'));
    markerLine.setAttribute('width', 1);
    markerLine.setAttribute('stroke', 'none');
    markerLine.setAttribute('stroke-width', '0');
    markerLine.setAttribute('fill', '#000000');
    svg.appendChild(markerLine);
  }

  google.visualization.events.addListener(chart, 'ready', function () {
    // add marker for current date
    addMarker(new Date(), 3, 'Test Event');
  });

  window.addEventListener('resize', drawChart, false);
  drawChart();
});

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