class Date

# File lib/dates_toolbox.rb, line 49
def day_of_the_week(date1, format_string = format)
    parse_date(date1, format_string).wday
end

# File lib/dates_toolbox.rb, line 57
def day_of_the_week_name(date1, format_string = format)
    Date::DAYNAMES[day_of_the_week(date1, format_string)]
end

# File lib/dates_toolbox.rb, line 65
def day_of_the_year(date1, format_string = format)
    parse_date(date1, format_string).yday
end

# File lib/dates_toolbox.rb, line 69
def days_between(date1, date2, format_string = format)
    d1 = parse_date(date1, format_string)
    d2 = parse_date(date2, format_string)

    d2.mjd - d1.mjd
end

# File lib/dates_toolbox.rb, line 45
def dotw(date1, format_string = format)
    day_of_the_week(date1, format_string)
end

# File lib/dates_toolbox.rb, line 53
def dotwn(date1, format_string = format)
    day_of_the_week_name(date1, format_string)
end

# File lib/dates_toolbox.rb, line 61
def doty(date1, format_string = format)
    day_of_the_year(date1, format_string)
end

# File lib/dates_toolbox.rb, line 24
def parse_date(date1, format_string)
    begin
        return Date.strptime(date1, format_string)
    rescue ArgumentError => e
        puts "Invalid date #{date1} with format #{format}"
        throw e
    end
end

# File lib/dates_toolbox.rb, line 20
def test_format
    (parse_date('1/1/1970', format).wday == 6)
end

# File lib/dates_toolbox.rb, line 33
def the_day(date1, format_string = format)
    parse_date(date1, format_string).day
end

# File lib/dates_toolbox.rb, line 37
def the_month(date1, format_string = format)
    parse_date(date1, format_string).month
end

# File lib/dates_toolbox.rb, line 41
def the_year(date1, format_string = format)
    parse_date(date1, format_string).year
end

# File lib/dates_toolbox.rb, line 90
def weekdays(date1, date2, format_string = format)
    start_date = parse_date(date1, format_string)
    end_date = parse_date(date2, format_string)

    # day of the week in 0-6. Sunday is day-of-week 0; Saturday is day-of-week 6.
    my_days = (1..5).to_a
    (start_date..end_date).to_a.select { |k| my_days.include?(k.wday) }
end

# File lib/dates_toolbox.rb, line 99
def weekdays_string(date1, date2, format_string = format)
    weekdays(date1, date2, format_string).map { |n| n.strftime(format) }
end

# File lib/dates_toolbox.rb, line 76
def weekends(date1, date2, format_string = format)
    start_date = parse_date(date1, format_string)
    end_date = parse_date(date2, format_string)

    # day of the week in 0-6. Sunday is day-of-week 0; Saturday is day-of-week 6.
    my_days = [0, 6]

    (start_date..end_date).to_a.select { |k| my_days.include?(k.wday) }
end

# File lib/dates_toolbox.rb, line 86
def weekends_string(date1, date2, format_string = format)
    weekends(date1, date2, format_string).map { |n| n.strftime(format) }
end