/* $Id$ */

#include "stdafx.h"
#include "openttd.h"
#include "date.h"
#include "variables.h"
#include "macros.h"
#include "vehicle.h"
#include "network.h"
#include "network_data.h"
#include "network_server.h"
#include "functions.h"
#include "currency.h"

Year      _cur_year;
Month     _cur_month;
Date      _date;
DateFract _date_fract;


void SetDate(Date date)
{
	YearMonthDay ymd;

	_date = date;
	ConvertDateToYMD(date, &ymd);
	_cur_year = ymd.year;
	_cur_month = ymd.month;
#ifdef ENABLE_NETWORK
	_network_last_advertise_frame = 0;
	_network_need_advertise = true;
#endif /* ENABLE_NETWORK */
}

#define M(a, b) ((a << 5) | b)
static const uint16 _month_date_from_year_day[] = {
M(0,1),M(0,2),M(0,3),M(0,4),M(0,5),M(0,6),M(0,7),M(0,8),M(0,9),M(0,10),M(0,11),M(0,12),M(0,13),M(0,14),M(0,15),M(0,16),M(0,17),M(0,18),M(0,19),M(0,20),M(0,21),M(0,22),M(0,23),M(0,24),M(0,25),M(0,26),M(0,27),M(0,28),M(0,29),M(0,30),M(0,31),
M(1,1),M(1,2),M(1,3),M(1,4),M(1,5),M(1,6),M(1,7),M(1,8),M(1,9),M(1,10),M(1,11),M(1,12),M(1,13),M(1,14),M(1,15),M(1,16),M(1,17),M(1,18),M(1,19),M(1,20),M(1,21),M(1,22),M(1,23),M(1,24),M(1,25),M(1,26),M(1,27),M(1,28),M(1,29),
M(2,1),M(2,2),M(2,3),M(2,4),M(2,5),M(2,6),M(2,7),M(2,8),M(2,9),M(2,10),M(2,11),M(2,12),M(2,13),M(2,14),M(2,15),M(2,16),M(2,17),M(2,18),M(2,19),M(2,20),M(2,21),M(2,22),M(2,23),M(2,24),M(2,25),M(2,26),M(2,27),M(2,28),M(2,29),M(2,30),M(2,31),
M(3,1),M(3,2),M(3,3),M(3,4),M(3,5),M(3,6),M(3,7),M(3,8),M(3,9),M(3,10),M(3,11),M(3,12),M(3,13),M(3,14),M(3,15),M(3,16),M(3,17),M(3,18),M(3,19),M(3,20),M(3,21),M(3,22),M(3,23),M(3,24),M(3,25),M(3,26),M(3,27),M(3,28),M(3,29),M(3,30),
M(4,1),M(4,2),M(4,3),M(4,4),M(4,5),M(4,6),M(4,7),M(4,8),M(4,9),M(4,10),M(4,11),M(4,12),M(4,13),M(4,14),M(4,15),M(4,16),M(4,17),M(4,18),M(4,19),M(4,20),M(4,21),M(4,22),M(4,23),M(4,24),M(4,25),M(4,26),M(4,27),M(4,28),M(4,29),M(4,30),M(4,31),
M(5,1),M(5,2),M(5,3),M(5,4),M(5,5),M(5,6),M(5,7),M(5,8),M(5,9),M(5,10),M(5,11),M(5,12),M(5,13),M(5,14),M(5,15),M(5,16),M(5,17),M(5,18),M(5,19),M(5,20),M(5,21),M(5,22),M(5,23),M(5,24),M(5,25),M(5,26),M(5,27),M(5,28),M(5,29),M(5,30),
M(6,1),M(6,2),M(6,3),M(6,4),M(6,5),M(6,6),M(6,7),M(6,8),M(6,9),M(6,10),M(6,11),M(6,12),M(6,13),M(6,14),M(6,15),M(6,16),M(6,17),M(6,18),M(6,19),M(6,20),M(6,21),M(6,22),M(6,23),M(6,24),M(6,25),M(6,26),M(6,27),M(6,28),M(6,29),M(6,30),M(6,31),
M(7,1),M(7,2),M(7,3),M(7,4),M(7,5),M(7,6),M(7,7),M(7,8),M(7,9),M(7,10),M(7,11),M(7,12),M(7,13),M(7,14),M(7,15),M(7,16),M(7,17),M(7,18),M(7,19),M(7,20),M(7,21),M(7,22),M(7,23),M(7,24),M(7,25),M(7,26),M(7,27),M(7,28),M(7,29),M(7,30),M(7,31),
M(8,1),M(8,2),M(8,3),M(8,4),M(8,5),M(8,6),M(8,7),M(8,8),M(8,9),M(8,10),M(8,11),M(8,12),M(8,13),M(8,14),M(8,15),M(8,16),M(8,17),M(8,18),M(8,19),M(8,20),M(8,21),M(8,22),M(8,23),M(8,24),M(8,25),M(8,26),M(8,27),M(8,28),M(8,29),M(8,30),
M(9,1),M(9,2),M(9,3),M(9,4),M(9,5),M(9,6),M(9,7),M(9,8),M(9,9),M(9,10),M(9,11),M(9,12),M(9,13),M(9,14),M(9,15),M(9,16),M(9,17),M(9,18),M(9,19),M(9,20),M(9,21),M(9,22),M(9,23),M(9,24),M(9,25),M(9,26),M(9,27),M(9,28),M(9,29),M(9,30),M(9,31),
M(10,1),M(10,2),M(10,3),M(10,4),M(10,5),M(10,6),M(10,7),M(10,8),M(10,9),M(10,10),M(10,11),M(10,12),M(10,13),M(10,14),M(10,15),M(10,16),M(10,17),M(10,18),M(10,19),M(10,20),M(10,21),M(10,22),M(10,23),M(10,24),M(10,25),M(10,26),M(10,27),M(10,28),M(10,29),M(10,30),
M(11,1),M(11,2),M(11,3),M(11,4),M(11,5),M(11,6),M(11,7),M(11,8),M(11,9),M(11,10),M(11,11),M(11,12),M(11,13),M(11,14),M(11,15),M(11,16),M(11,17),M(11,18),M(11,19),M(11,20),M(11,21),M(11,22),M(11,23),M(11,24),M(11,25),M(11,26),M(11,27),M(11,28),M(11,29),M(11,30),M(11,31),
};
#undef M

enum {
	ACCUM_JAN = 0,
	ACCUM_FEB = ACCUM_JAN + 31,
	ACCUM_MAR = ACCUM_FEB + 29,
	ACCUM_APR = ACCUM_MAR + 31,
	ACCUM_MAY = ACCUM_APR + 30,
	ACCUM_JUN = ACCUM_MAY + 31,
	ACCUM_JUL = ACCUM_JUN + 30,
	ACCUM_AUG = ACCUM_JUL + 31,
	ACCUM_SEP = ACCUM_AUG + 31,
	ACCUM_OCT = ACCUM_SEP + 30,
	ACCUM_NOV = ACCUM_OCT + 31,
	ACCUM_DEC = ACCUM_NOV + 30,
};

static const uint16 _accum_days_for_month[] = {
	ACCUM_JAN, ACCUM_FEB, ACCUM_MAR, ACCUM_APR,
	ACCUM_MAY, ACCUM_JUN, ACCUM_JUL, ACCUM_AUG,
	ACCUM_SEP, ACCUM_OCT, ACCUM_NOV, ACCUM_DEC,
};


void ConvertDateToYMD(Date date, YearMonthDay *ymd)
{
	uint yr  = date / (365 + 365 + 365 + 366);
	uint rem = date % (365 + 365 + 365 + 366);
	uint x;

	yr *= 4;

	if (rem >= 366) {
		rem--;
		do {
			rem -= 365;
			yr++;
		} while (rem >= 365);
		if (rem >= 31 + 28) rem++;
	}

	ymd->year = yr;

	x = _month_date_from_year_day[rem];
	ymd->month = x >> 5;
	ymd->day = x & 0x1F;
}

/**
 * Converts a tupe of Year, Month and Day to a Date.
 * @param year  is a number between 0..?
 * @param month is a number between 0..11
 * @param day   is a number between 1..31
 */
Date ConvertYMDToDate(Year year, Month month, Day day)
{
	uint rem;

	/* day in the year */
	rem = _accum_days_for_month[month] + day - 1;

	/* remove feb 29 from year 1,2,3 */
	if (year & 3) rem += (year & 3) * 365 + (rem < 31 + 29);

	/* base date. */
	return (year >> 2) * (365 + 365 + 365 + 366) + rem;
}

/**
 * Convert a date on the form:
 * 1920 - 2090 (MAX_YEAR_END_REAL)
 * 192001 - 209012
 * 19200101 - 20901231
 * or if > 2090 and below 65536, treat it as a daycount.
 * @return -1 if no conversion was possible
 */
Date ConvertIntDate(uint date)
{
	Year  year;
	Month month = 0;
	Day   day   = 1;

	if (IS_INT_INSIDE(date, 1920, MAX_YEAR + 1)) {
		year = date - 1920;
	} else if (IS_INT_INSIDE(date, 192001, 209012 + 1)) {
		month = date % 100 - 1;
		year = date / 100 - 1920;
	} else if (IS_INT_INSIDE(date, 19200101, 20901231 + 1)) {
		day = date % 100; date /= 100;
		month = date % 100 - 1;
		year = date / 100 - 1920;
	} else if (IS_INT_INSIDE(date, 2091, 65536)) {
		return date;
	} else {
		return (Date)-1;
	}

	/* invalid ranges? */
	if (month >= 12 || !IS_INT_INSIDE(day, 1, 31 + 1)) return (Date)-1;

	return ConvertYMDToDate(year, month, day);
}


/** Functions used by the IncreaseDate function */

extern void OnNewDay_Train(Vehicle *v);
extern void OnNewDay_RoadVeh(Vehicle *v);
extern void OnNewDay_Aircraft(Vehicle *v);
extern void OnNewDay_Ship(Vehicle *v);
static void OnNewDay_EffectVehicle(Vehicle *v) { /* empty */ }
extern void OnNewDay_DisasterVehicle(Vehicle *v);

typedef void OnNewVehicleDayProc(Vehicle *v);

static OnNewVehicleDayProc * _on_new_vehicle_day_proc[] = {
	OnNewDay_Train,
	OnNewDay_RoadVeh,
	OnNewDay_Ship,
	OnNewDay_Aircraft,
	OnNewDay_EffectVehicle,
	OnNewDay_DisasterVehicle,
};

extern void WaypointsDailyLoop(void);
extern void TextMessageDailyLoop(void);
extern void EnginesDailyLoop(void);
extern void DisasterDailyLoop(void);

extern void PlayersMonthlyLoop(void);
extern void EnginesMonthlyLoop(void);
extern void TownsMonthlyLoop(void);
extern void IndustryMonthlyLoop(void);
extern void StationMonthlyLoop(void);

extern void PlayersYearlyLoop(void);
extern void TrainsYearlyLoop(void);
extern void RoadVehiclesYearlyLoop(void);
extern void AircraftYearlyLoop(void);
extern void ShipsYearlyLoop(void);

extern void ShowEndGameChart(void);


static const Month _autosave_months[] = {
	 0, // never
	 1, // every month
	 3, // every 3 months
	 6, // every 6 months
	12, // every 12 months
};

/**
 * Runs the day_proc for every DAY_TICKS vehicle starting at daytick.
 */
static void RunVehicleDayProc(uint daytick)
{
	uint total = _vehicle_pool.total_items;
	uint i;

	for (i = daytick; i < total; i += DAY_TICKS) {
		Vehicle *v = GetVehicle(i);

		if (v->type != 0) _on_new_vehicle_day_proc[v->type - 0x10](v);
	}
}

void IncreaseDate(void)
{
	YearMonthDay ymd;

	if (_game_mode == GM_MENU) {
		_tick_counter++;
		return;
	}

	RunVehicleDayProc(_date_fract);

	/* increase day, and check if a new day is there? */
	_tick_counter++;

	_date_fract++;
	if (_date_fract < DAY_TICKS) return;
	_date_fract = 0;

	/* yeah, increase day counter and call various daily loops */
	_date++;

	TextMessageDailyLoop();

	DisasterDailyLoop();
	WaypointsDailyLoop();

	if (_game_mode != GM_MENU) {
		InvalidateWindowWidget(WC_STATUS_BAR, 0, 0);
		EnginesDailyLoop();
	}

	/* check if we entered a new month? */
	ConvertDateToYMD(_date, &ymd);
	if (ymd.month == _cur_month) return;
	_cur_month = ymd.month;

	/* yes, call various monthly loops */
	if (_game_mode != GM_MENU) {
		if (_opt.autosave != 0 && (_cur_month % _autosave_months[_opt.autosave]) == 0) {
			_do_autosave = true;
			RedrawAutosave();
		}

		PlayersMonthlyLoop();
		EnginesMonthlyLoop();
		TownsMonthlyLoop();
		IndustryMonthlyLoop();
		StationMonthlyLoop();
#ifdef ENABLE_NETWORK
		if (_network_server) NetworkServerMonthlyLoop();
#endif /* ENABLE_NETWORK */
	}

	/* check if we entered a new year? */
	if (ymd.year == _cur_year) return;
	_cur_year = ymd.year;

	/* yes, call various yearly loops */
	PlayersYearlyLoop();
	TrainsYearlyLoop();
	RoadVehiclesYearlyLoop();
	AircraftYearlyLoop();
	ShipsYearlyLoop();
#ifdef ENABLE_NETWORK
	if (_network_server) NetworkServerYearlyLoop();
#endif /* ENABLE_NETWORK */

	/* check if we reached end of the game */
	if (_cur_year == _patches.ending_year - MAX_YEAR) {
			ShowEndGameChart();
	/* check if we reached the maximum year, decrement dates by a year */
	} else if (BASE_YEAR + _cur_year == MAX_YEAR + 1) {
		Vehicle *v;

		_cur_year--;
		_date -= 365;
		FOR_ALL_VEHICLES(v) {
			v->date_of_last_service -= 365;
		}

		/* Because the _date wraps here, and text-messages expire by game-days, we have to clean out
		 *  all of them if the date is set back, else those messages will hang for ever */
		InitTextMessage();
	}

	if (_patches.auto_euro) CheckSwitchToEuro();
}