minetest_calendar/init.lua

calendar = {}
local S
if minetest.get_translator then
	S = minetest.get_translator("calendar")
else
	S = function(s) return s end
end
local F = minetest.formspec_escape

dofile(minetest.get_modpath("calendar").."/gameconfig.lua")

-- Number of months in a year
calendar.MONTHS = #calendar.month_names
-- Number of days in a week
calendar.WEEK_DAYS = #calendar.weekday_names
-- Number of days in a year
calendar.YEAR_DAYS = calendar.MONTHS * calendar.MONTH_DAYS

local holidays = {}

calendar.register_holiday = function(def)
	table.insert(holidays, def)
end

-- Example holidays
calendar.register_holiday({
	name = S("New Year's Eve"),
	type = "monthday",
	days = 0,
	months = 0
})

calendar.register_holiday({
	name = S("Mother's Day"),
	type = "custom",
	-- First Sunday in May
	is_holiday = function(total_days)
		local d, m, y = calendar.get_date(total_days)
		local wday = calendar.get_weekday(total_days)
		return wday == 6 and m == 4 and d <= 6
	end,
})

calendar.get_holidays = function(total_days)
	if not total_days then
		total_days = minetest.get_day_count()
	end
	local days, months, years = calendar.get_date(total_days)
	local found_holidays = {}
	for h=1, #holidays do
		local holiday = holidays[h]
		if holiday.type == "monthday" then
			if holiday.days == days and holiday.months == months and (holiday.years == nil or holiday.years == years) then
				table.insert(found_holidays, holiday)
			end
		elseif holiday.type == "custom" then
			if holiday.is_holiday(total_days) == true then
				table.insert(found_holidays, holiday)
			end
		else
			minetest.log("error", "[calender] Invalid holiday type: "..tostring(holiday.type))
		end
	end
	return found_holidays
end

calendar.get_weekday = function(total_days)
	if not total_days then
		total_days = minetest.get_day_count()
	end
	return (total_days + calendar.FIRST_WEEK_DAY) % calendar.WEEK_DAYS
end

calendar.get_date = function(total_days, ordinal)
	if not total_days then
		total_days = minetest.get_day_count()
	end

	local y = math.floor(total_days / calendar.YEAR_DAYS) -- elapsed years in epoch
	local m = math.floor(total_days % calendar.YEAR_DAYS / calendar.MONTH_DAYS) -- elapsed months in year
	local d = math.floor(total_days % calendar.YEAR_DAYS % calendar.MONTH_DAYS) -- elapsed days in month
	local j = math.floor(total_days % calendar.YEAR_DAYS) -- elapsed days in year

	if ordinal == nil then
		ordinal = false
	end
	if ordinal then
		y = y + 1
		m = m + 1
		d = d + 1
		j = j + 1
	end
	return d, m, y, j
end

calendar.get_date_string = function(format, total_days)
	if not total_days then
		total_days = minetest.get_day_count()
	end

	if format == nil then
		format = S("%D days, %M months, %Y years")
	end

	local y, m, d, j = calendar.get_date(total_days)

	-- cardinal values
	format = string.gsub( format, "%%Y", y )	      -- elapsed years in epoch
	format = string.gsub( format, "%%M", m )	      -- elapsed months in year
	format = string.gsub( format, "%%D", d )	      -- elapsed days in month
	format = string.gsub( format, "%%J", j )	      -- elapsed days in year

	-- ordinal values
	format = string.gsub( format, "%%y", y + 1 )	  -- current year of epoch
	format = string.gsub( format, "%%m", m + 1 )	  -- current month of year
	format = string.gsub( format, "%%d", d + 1 )	  -- current day of month
	format = string.gsub( format, "%%j", j + 1 )	  -- current day of year

	format = string.gsub( format, "%%b", S(calendar.month_names[ m + 1 ]) )       -- current month long name
	format = string.gsub( format, "%%h", S(calendar.month_names_short[ m + 1 ]) )       -- current month short name

	format = string.gsub( format, "%%b", S(calendar.month_names[ m + 1 ]) )       -- current month long name
	format = string.gsub( format, "%%h", S(calendar.month_names_short[ m + 1 ]) )       -- current month short name

	format = string.gsub( format, "%%z", "%%" )

	return format
end

dofile(minetest.get_modpath("calendar").."/gui.lua")
dofile(minetest.get_modpath("calendar").."/command.lua")
dofile(minetest.get_modpath("calendar").."/node.lua")