/// <summary>
/// Takes a date/time which and determines a friendly string for time from now to be displayed for the relative time from the date.
/// It is important to note that times are compared using the current timezone, so the date that is passed in should be converted
/// to the local timezone before passing it in.
/// </summary>
/// <param name="originDate">Current date.</param>
/// <param name="previousDate">The date to get relative time string for.</param>
/// <param name="displayWeeks">Indicates whether to display weeks.</param>
/// <returns>The human readable string for relative date.</returns>
/// <see href="http://stackoverflow.com/questions/11/how-do-i-calculate-relative-time"/>
public static string GetRelativeDateString(DateTime originDate, DateTime previousDate, bool displayWeeks = true)
{
var ts = new TimeSpan(RoundDateTime(originDate).Ticks - RoundDateTime(previousDate).Ticks);
double delta = Math.Abs(ts.TotalSeconds);
if (delta < 60)
{
return(Strings.GetNSecondsAgoText(ts.Seconds));
}
if (delta < 45 * 60)
{
return(Strings.GetNMinutesAgoText(ts.Minutes));
}
if (delta < 24 * 60 * 60)
{
int hours = delta < 60 * 60 ? Math.Sign(ts.Minutes) * 1 : ts.Hours;
return(Strings.GetNHoursAgoText(hours));
}
// 30.417 = 365 days / 12 months - note that the if statement only bothers with 30 days for "1 month ago" because ts.Days is int
if (delta < (displayWeeks ? 7 : 30) * 24 * 60 * 60)
{
return(Strings.GetNDaysAgoText(ts.Days));
}
if (displayWeeks && delta < 30 * 24 * 60 * 60)
{
int weeks = Convert.ToInt32(ts.Days / 7.0);
return(Strings.GetNWeeksAgoText(weeks));
}
if (delta < 365 * 24 * 60 * 60)
{
int months = Convert.ToInt32(ts.Days / 30.0);
return(Strings.GetNMonthsAgoText(months));
}
int years = Convert.ToInt32(ts.Days / 365.0);
return(Strings.GetNYearsAgoText(years));
}