How to create Google Analytics like Users chart in Highchart React - reactjs

Question

I am trying to create a comparison graph like the one below which will show the data of the current day vs the present day minus 7 days (or 20 days or 90 days, ...).
I am using highcharts and highchart's react wrapper for this and I've created a multi line graph using the following data:
series: [
{
name: "Weekly",
data: [
24916, 37941, 29742, 29851, 32490, 30282, 38121, 36885, 33726, 34243,
31050,
],
},
{
name: "Weekly Last Week",
data: [
11744, 30000, 16005, 19771, 20185, 24377, 32147, 30912, 29243, 29213,
25663,
],
dashStyle: "ShortDash",
},
]
I am able to create the same solid and dashed line effect. The only issue I am facing is how to show the tooltip (as shown in the image below) with the current date vs last date data and their comparison. I used this tooltip option:
tooltip: {
enabled: true,
shared: true,
formatter: function () {
return this.points.reduce(function (s, point) {
return s + "<br/>" + point.series.name + ": " + point.y + "m";
}, "<b>" + this.x + "</b>");
},
},

Answer 1

I was able to recreate it based on the design requirement we had. Here is the link to the codesandbox (minus the proper design for tooltips and legends) for anyone looking for it in the future.
The tooltip's functionality was achieved by adding the formatter function in the tooltip option (found in the chartOptions.js file in the sandbox). It's a hacky code but it is needed to calculate the percentage change between the current day's data vs last week's (present-day minus 7 days) data. In my current case, all data is restricted to 7 days for the time being.
For creating the legend which shows the same percent change data I need to add an empty series in the series data (found in the chartOptions.js file) which will store the calculated value of the percent change of the last day (basically the last value in the array).
If anyone has a better solution for consuming data inside the formatter function of the tooltip or legends then please add it to the answer to this question.