TimeSpan Readable Ago String

TimeSpanExtensions.cs

public static class TimeSpanExtensions
{
    // Inspired by @Peter answear from https://stackoverflow.com/questions/842057/how-do-i-convert-a-timespan-to-a-formatted-string
    public static string ToReadableAgoString(this TimeSpan span, double justNowSecondsThreshold)
    {
        if (span.TotalSeconds < justNowSecondsThreshold)
            return "just now";

        return span switch
        {
            TimeSpan { TotalDays: > 1 } => string.Format("{0:0} day{1} ago", span.Days, span.Days == 1 ? string.Empty : "s"),
            TimeSpan { TotalHours: > 1 } => string.Format("{0:0} hour{1} ago", span.Hours, span.Hours == 1 ? string.Empty : "s"),
            TimeSpan { TotalMinutes: > 1 } => string.Format("{0:0} minute{1} ago", span.Minutes, span.Minutes == 1 ? string.Empty : "s"),
            _ => string.Format("{0:0} second{1} ago", span.Seconds, span.Seconds == 1 ? string.Empty : "s")
        };
    }
}