(async function() {
  const chartData = {
    datasets: [{
      label: 'Relative Humidity',
      data: [{"x":0,"y":81},{"x":-1,"y":82},{"x":-2,"y":78},{"x":-3,"y":68},{"x":-4,"y":72},{"x":-5,"y":72},{"x":-6,"y":83},{"x":-7,"y":86},{"x":-8,"y":87},{"x":-9,"y":84},{"x":-10,"y":83},{"x":-11,"y":88},{"x":-12,"y":88},{"x":-13,"y":84},{"x":-14,"y":82},{"x":-15,"y":85},{"x":-16,"y":85},{"x":-17,"y":91},{"x":-18,"y":91},{"x":-19,"y":90},{"x":-20,"y":92},{"x":-21,"y":93},{"x":-22,"y":94},{"x":-23,"y":94}],
      backgroundColor: '#87C404'
    }]
  }
  
  ctx = document.getElementById('relativeHumidity').getContext('2d');
  chart = new Chart(ctx, {
    type: 'scatter',
    data: chartData,
    showLine: true,
    options: {
      scales: {
        x: {
          title: {
            display: true,
            text: 'Hours',
            font: {
              size: 16
            },
          }
        },
        y: {
          title: {
            display: true,
            text: '%',
            font: {
              size: 16
            },
          }
        }
      }
    }
  })
  if(chartData.datasets[0].data.length === 0) {
    const width = chart.width
    const height = chart.height
    const chart_ctx = chart.ctx;
    var fontSize = (height / 114).toFixed(2);
    chart_ctx.font = fontSize + "em sans-serif";
    chart_ctx.fillStyle = "red";
    chart_ctx.textBaseline = "middle";

    var text = 'No Data',
        textX = Math.round((width - ctx.measureText(text).width) / 2),
        textY = height / 2;

    ctx.fillText(text, textX, textY);
  }
})();