/// <summary>
/// Caculates the number of business days between two dates given a list of public holidays
/// </summary>
public static double BusinessDaysBetweenTwoDates(DateTime firstDate, DateTime secondDate, IList <DateTime> publicHolidays)
{
//Compare supplied dates
if (ValidateInputDates(firstDate, secondDate))
{
return(0);
}
//Get the date range between the two dates excluding firstDate and secondDate
var dateRange = DayCounterHelper.GetDateRangeBetweenTwoDates(firstDate, secondDate);
//Count the number of dates that are a business day
//A business day is a week day that is either a full day or a half day
//A public holiday is either defined as a full public holiday or a half public holiday
//When comparing Hour, it uses the 24 format therefore it is safe to assume that 12 means 12pm otherwise it would be 0
//A half public holidays is defined as a date with the time set to 12PM
var halfDayPublicHolidays = publicHolidays.Where(d => d.Hour == 12);
var fullDayPublicHolidays = publicHolidays.Where(d => d.Hour != 12);
//First get the true full business days (a half day is not a full business day, so we need to pass the half day list)
var fullBusinessDays = DayCounterHelper.GetFullBusinessDays(dateRange, fullDayPublicHolidays, halfDayPublicHolidays);
//Then get the true half business days
var halfBusinessDays = DayCounterHelper.GetHalfBusinessDays(dateRange, fullDayPublicHolidays, halfDayPublicHolidays);
//Return the count
return((double)fullBusinessDays.Count() + ((double)halfBusinessDays.Count() / 2));
}