discourse/app/assets/javascripts/admin/addon/components/admin-report-stacked-chart.gjs

import Component from "@glimmer/component";
import { number } from "discourse/lib/formatter";
import { makeArray } from "discourse-common/lib/helpers";
import Report from "admin/models/report";
import Chart from "./chart";

export default class AdminReportStackedChart extends Component {
  get chartConfig() {
    const { model } = this.args;

    const chartData = makeArray(model.chartData || model.data).map((cd) => ({
      label: cd.label,
      color: cd.color,
      data: Report.collapse(model, cd.data),
    }));

    const data = {
      labels: chartData[0].data.mapBy("x"),
      datasets: chartData.map((cd) => ({
        label: cd.label,
        stack: "pageviews-stack",
        data: cd.data,
        backgroundColor: cd.color,
      })),
    };

    return {
      type: "bar",
      data,
      options: {
        responsive: true,
        maintainAspectRatio: false,
        responsiveAnimationDuration: 0,
        hover: { mode: "index" },
        animation: {
          duration: 0,
        },
        plugins: {
          tooltip: {
            mode: "index",
            intersect: false,
            callbacks: {
              beforeFooter: (tooltipItem) => {
                const total = tooltipItem.reduce(
                  (sum, item) => sum + parseInt(item.parsed.y || 0, 10),
                  0
                );
                return `= ${total}`;
              },
              title: (tooltipItem) =>
                moment(tooltipItem[0].label, "YYYY-MM-DD").format("LL"),
            },
          },
        },

        layout: {
          padding: {
            left: 0,
            top: 0,
            right: 0,
            bottom: 0,
          },
        },
        scales: {
          y: [
            {
              stacked: true,
              display: true,
              ticks: {
                callback: (label) => number(label),
                sampleSize: 5,
                maxRotation: 25,
                minRotation: 25,
              },
            },
          ],
          x: [
            {
              display: true,
              gridLines: { display: false },
              type: "time",
              time: {
                unit: Report.unitForDatapoints(data.labels.length),
              },
              ticks: {
                sampleSize: 5,
                maxRotation: 50,
                minRotation: 50,
              },
            },
          ],
        },
      },
    };
  }

  <template>
    <Chart
      @chartConfig={{this.chartConfig}}
      class="admin-report-chart admin-report-stacked-chart"
    />
  </template>
}