OpenTTD/src/script/api/script_date.hpp

117 lines
4.3 KiB
C++

/*
* This file is part of OpenTTD.
* OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
* OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
* See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
*/
/** @file script_date.hpp Everything to query and manipulate date related information. */
#ifndef SCRIPT_DATE_HPP
#define SCRIPT_DATE_HPP
#include "script_object.hpp"
#include "../../timer/timer_game_economy.h"
/**
* Class that handles all date related (calculation) functions.
* @api ai game
*
* @note Months and days of month are 1-based; the first month of the
* year is 1 and the first day of the month is also 1.
* @note Years are zero based; they start with the year 0.
* @note Dates can be used to determine the number of days between
* two different moments in time because they count the number
* of days since the year 0.
*
* \anchor ScriptCalendarTime
* \b Calendar-Time
*
* Calendar time measures the technological progression in the game.
* \li The calendar date is shown in the status bar.
* \li The calendar date affects engine model introduction and expiration.
* \li Progression of calendar time can be slowed or even halted via game settings.
*
* Calendar time uses the Gregorian calendar with 365 or 366 days per year.
*
* \anchor ScriptEconomyTime
* \b Economy-Time
*
* Economy time measures the in-game time progression, while the game is not paused.
* \li Cargo production and consumption follows economy time.
* \li Recurring income and expenses follow economy time.
* \li Production and income statistics and balances are created per economy month/quarter/year.
*
* Depending on game settings economy time is represented differently:
* \li Calendar-based timekeeping: Economy- and calendar-time use the identical Gregorian calendar.
* \li Wallclock-based timekeeping: Economy- and calendar-time are separate.
* Economy-time will use a 360 day calendar (12 months with 30 days each), which runs at a constant speed of one economy-month per realtime-minute.
* Calendar-time will use a Gregorian calendar, which can be slowed to stopped via game settings.
*/
class ScriptDate : public ScriptObject {
public:
/**
* Date data type is an integer value. Use ScriptDate::GetDate to
* compose valid date values for a known year, month and day.
*/
enum Date {
DATE_INVALID = ::EconomyTime::INVALID_DATE.base(), ///< A value representing an invalid date.
};
/**
* Validates if a date value represent a valid date.
* @param date The date to validate.
* @return True if the date is valid, otherwise false
*/
static bool IsValidDate(Date date);
/**
* Get the current date.
* This is the number of days since epoch under the assumption that
* there is a leap year every 4 years, except when dividable by
* 100 but not by 400.
* @return The current date.
*/
static Date GetCurrentDate();
/**
* Get the year of the given date.
* @param date The date to get the year of.
* @return The year.
*/
static SQInteger GetYear(Date date);
/**
* Get the month of the given date.
* @param date The date to get the month of.
* @return The month.
*/
static SQInteger GetMonth(Date date);
/**
* Get the day (of the month) of the given date.
* @param date The date to get the day of.
* @return The day.
*/
static SQInteger GetDayOfMonth(Date date);
/**
* Get the date given a year, month and day of month.
* @param year The year of the to-be determined date.
* @param month The month of the to-be determined date.
* @param day_of_month The day of month of the to-be determined date.
* @return The date.
*/
static Date GetDate(SQInteger year, SQInteger month, SQInteger day_of_month);
/**
* Get the time of the host system.
* @return The amount of seconds passed since 1 Jan 1970.
* @api -ai
* @note This uses the clock of the host system, which can skew or be set back. Use with caution.
*/
static SQInteger GetSystemTime();
};
#endif /* SCRIPT_DATE_HPP */