How to use different date formats in chart js

[redwarbanner]

I have a selectbox with different periods:

• year
• month
• week
  if i select "week" - the period of 7 days from the current day is calculated.T hen the chart for the previous 7 days is plotted. The graph is plotted correctly, but there is a problem with the x-axis. I can set the data format for month, week, or another something like this:

    scales: {
                xAxes: [
                    {
                        type: "time",
                        time: {

                            format: "DD.MM.YYYY HH:mm",
                            unit: month,
                             displayFormats: {
                                'week': 'DD.MM',
                                'month': 'DD.MM',
                                'year': 'MMMM',
                            },
                        },
                    },
                ],
            },

how do I change the unit depending on the format?
I tried using a global variable call window.variable - but its didn't work.
Also, only one date is displayed on the chart

[stockiNail]

@redwarbanner if I understood well your need, at runtime, you could try to change the unit by chart.options and then update the chart.
Inside the function which is catching the change event on list box, you could:

  chart.options.scales.x.time.unit = 'week'; // or month or year based on the list box selection
  chart.update();