godot date/time helper class in GDScript

DateHelper.gd

class_name DateHelper

static func date_add_days(date: Dictionary, days_to_add: int = 1) -> Dictionary:
	assert(date.has("month"), "the date Dictionary must have a month")
	assert(date.has("day"), "the date Dictionary must have a month")
	assert(date.has("year"), "the date Dictionary must have a year")

	var to_unix = OS.get_unix_time_from_datetime(date) + (86400 * days_to_add)
	return OS.get_datetime_from_unix_time(to_unix)


static func datetime_add_seconds(datetime: Dictionary, seconds_to_add: int = 1) -> Dictionary:
	assert(datetime.has("second"), "the date Dictionary must have a second")
	assert(datetime.has("minute"), "the date Dictionary must have a minute")
	assert(datetime.has("hour"), "the date Dictionary must have an hour")

	var to_unix = OS.get_unix_time_from_datetime(datetime) + seconds_to_add
	return OS.get_datetime_from_unix_time(to_unix)


static func is_leap_year(year: int) -> bool:
	return true if year % 4 == 0 else false


static func get_days_in_month(month: int) -> int:
	var d = OS.get_date(true)
	var leap = is_leap_year(d.year)
	match month:
		1, 3, 5, 7, 8, 10, 12:
			return 31
		2:
			return 29 if leap else 28
		_:
			return 30