<?php
/**********************************************************************
    Copyright (C) FrontAccounting, LLC.
	Released under the terms of the GNU Affero General Public License,
	AGPL, as published by the Free Software Foundation, either version 
	3 of the License, or (at your option) any later version.
    This program 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 License here <http://www.gnu.org/licenses/agpl-3.0.html>.
***********************************************************************/
/*
date validation and parsing functions

These functions refer to the global variable defining the date format
The date format is defined in config.php called DefaultDateFormat
this can be a string either "d/m/Y" for UK/Australia/New Zealand dates or
"m/d/Y" for US/Canada format dates

*/

function __date($year, $month, $day)
{
	global $dateseps;
	
	$how = user_date_format();
	$sep = $dateseps[user_date_sep()];
	$day = (int)$day;
	$month = (int)$month;
	if ($day < 10)
		$day = "0".$day;
	if ($month < 10)
		$month = "0".$month;
	if ($how == 0)
		return $month.$sep.$day.$sep.$year;
	else if ($how == 1)
		return $day.$sep.$month.$sep.$year;
	else
		return $year.$sep.$month.$sep.$day;
}

function is_date($date_) 
{
	global $dateseps;

	if ($date_ == null || $date_ == "")
		return 0;
	$how = user_date_format();
	$sep = $dateseps[user_date_sep()];

	$date_ = trim($date_);
	$date_ = str_replace($sep, "", $date_);
	if (strlen($date_) == 6)
	{
		if ($how == 0)
		{
			$day = substr($date_,2,2);
			$month = substr($date_,0,2);
			$year = substr($date_,4,2);
		} 
		elseif ($how == 1)
		{
			$day = substr($date_,0,2);
			$month = substr($date_,2,2);
			$year = substr($date_,4,2);
		} 
		else
		{
			$day = substr($date_,4,2);
			$month = substr($date_,2,2);
			$year = substr($date_,0,2);
		}
	}
	elseif (strlen($date_) == 8)
	{
		if ($how == 0)
		{
			$day = substr($date_,2,2);
			$month = substr($date_,0,2);
			$year = substr($date_,4,4);
		} 
		elseif ($how == 1)
		{
			$day = substr($date_,0,2);
			$month = substr($date_,2,2);
			$year = substr($date_,4,4);
		} 
		else
		{
			$day = substr($date_,6,2);
			$month = substr($date_,4,2);
			$year = substr($date_,0,4);
		}
	}
	if (!isset($year)|| (int)$year > 9999) 
	{
		return 0;
	}


	if (is_long((int)$day) && is_long((int)$month) && is_long((int)$year))
	{
		global $date_system;
		if ($date_system == 1)
			list($year, $month, $day) = jalali_to_gregorian($year, $month, $day);  
		else if ($date_system == 2)	
			list($year, $month, $day) = islamic_to_gregorian($year, $month, $day);  
		if (checkdate((int)$month, (int)$day, (int)$year))
		{
			return 1;
		}
		else
		{
			return 0;
		}
	}
	else
	{ /*Can't be in an appropriate DefaultDateFormat */
		return 0;
	}
} //end of is_date function

function Today() 
{
	global $date_system;

	$year = date("Y");
	$month = date("n");
	$day = date("j");
	if ($date_system == 1)
		list($year, $month, $day) = gregorian_to_jalali($year, $month, $day);
	else if ($date_system == 2)	
		list($year, $month, $day) = gregorian_to_islamic($year, $month, $day);
	return __date($year, $month, $day);	
}

function Now() 
{
	if (user_date_format() == 0)
		return date("h:i a");
	else
		return date("H:i");
}

function is_date_in_fiscalyear($date, $convert=false)
{
	global $path_to_root;
	include_once($path_to_root . "/admin/db/company_db.inc");

	$myrow = get_current_fiscalyear();
	if ($myrow['closed'] == 1)
		return 0;
	if ($convert)
		$date2 = sql2date($date);
	else
		$date2 = $date;
	$begin = sql2date($myrow['begin']);
	$end = sql2date($myrow['end']);
	if (date1_greater_date2($begin, $date2) || date1_greater_date2($date2, $end))
	{
		return 0;
	}
	return 1;
}

function begin_fiscalyear()
{
	global $path_to_root;
	include_once($path_to_root . "/admin/db/company_db.inc");

	$myrow = get_current_fiscalyear();
	return sql2date($myrow['begin']);
}

function end_fiscalyear()
{
	global $path_to_root;
	include_once($path_to_root . "/admin/db/company_db.inc");

	$myrow = get_current_fiscalyear();
	return sql2date($myrow['end']);
}

function begin_month($date)
{
	global $date_system;
    list($day, $month, $year) = explode_date_to_dmy($date);
    if ($date_system == 1)
    	list($year, $month, $day) = gregorian_to_jalali($year, $month, $day);
    else if ($date_system == 2)	
    	list($year, $month, $day) = gregorian_to_islamic($year, $month, $day);
   	return __date($year, $month, 1);
}

function end_month($date)
{
	global $date_system;
    list($day, $month, $year) = explode_date_to_dmy($date);
	if ($date_system == 1)
	{
		list($year, $month, $day) = gregorian_to_jalali($year, $month, $day);
		$days_in_month = array(31, 31, 31, 31, 31, 31, 30, 30, 30, 30, 30, ((((((($year - (($year > 0) ? 474 : 473)) % 2820) + 474) + 38) * 682) % 2816) < 682 ? 30 : 29));
	}
	else if ($date_system == 2)
	{
		list($year, $month, $day) = gregorian_to_islamic($year, $month, $day);
		$days_in_month = array(30, 29, 30, 29, 30, 29, 30, 29, 30, 29, 30, (((((11 * $year) + 14) % 30) < 11) ? 30 : 29));
	}
	else // gregorian date
		$days_in_month = array(31, ((!($year % 4 ) && (($year % 100) || !($year % 400)))?29:28), 31, 30, 31, 30, 31, 31, 30, 31, 30, 31);
   	return __date($year, $month, $days_in_month[$month - 1]);
}

function add_days($date, $days) // accepts negative values as well
{
	global $date_system;
    list($day, $month, $year) = explode_date_to_dmy($date);
   	$timet = Mktime(0,0,0, $month, $day + $days, $year);
    if ($date_system == 1 || $date_system == 2)
    {
    	if ($date_system == 1)
    		list($year, $month, $day) = gregorian_to_jalali(date("Y", $timet), date("n", $timet), date("j", $timet));
    	else if ($date_system == 2) 	
    		list($year, $month, $day) = gregorian_to_islamic(date("Y", $timet), date("n", $timet), date("j", $timet));
    	return __date($year, $month, $day);
    }
    return date(user_date_display(), $timet);
}

function add_months($date, $months) // accepts negative values as well
{
	global $date_system;
    list($day, $month, $year) = explode_date_to_dmy($date);
   	$timet = Mktime(0,0,0, $month + $months, $day, $year);
    if ($date_system == 1 || $date_system == 2)
    {
    	if ($date_system == 1)
    		list($year, $month, $day) = gregorian_to_jalali(date("Y", $timet), date("n", $timet), date("j", $timet));
    	else if ($date_system == 2) 	
    		list($year, $month, $day) = gregorian_to_islamic(date("Y", $timet), date("n", $timet), date("j", $timet));
    	return __date($year, $month, $day);
    }
    return date(user_date_display(), $timet);
}

function add_years($date, $years) // accepts negative values as well
{
	global $date_system;
    list($day, $month, $year) = explode_date_to_dmy($date);
   	$timet = Mktime(0,0,0, $month, $day, $year + $years);
    if ($date_system == 1 || $date_system == 2)
    {
    	if ($date_system == 1)
    		list($year, $month, $day) = gregorian_to_jalali(date("Y", $timet), date("n", $timet), date("j", $timet));
    	else if ($date_system == 2) 	
    		list($year, $month, $day) = gregorian_to_islamic(date("Y", $timet), date("n", $timet), date("j", $timet));
    	return __date($year, $month, $day);
    }
    return date(user_date_display(), $timet);
}

//_______________________________________________________________

function sql2date($date_) 
{
	global $date_system;

	//for MySQL dates are in the format YYYY-mm-dd
	if ($date_ == null || strlen($date_) == 0)
		return "";

	if (strpos($date_, "/")) 
	{ // In MySQL it could be either / or -
		list($year, $month, $day) = explode("/", $date_);
	} 
	elseif (strpos ($date_, "-")) 
	{
		list($year, $month, $day) = explode("-", $date_);
	}

	if (strlen($day) > 4) 
	{  /*chop off the time stuff */
		$day = substr($day, 0, 2);
	}
	if ($date_system == 1)
		list($year, $month, $day) = gregorian_to_jalali($year, $month, $day);
	else if ($date_system == 2)
		list($year, $month, $day) = gregorian_to_islamic($year, $month, $day);
	return __date($year, $month, $day);	
} // end function sql2date


function date2sql($date_)
{
	global $dateseps, $date_system;
/* takes a date in a the format specified in $DefaultDateFormat
and converts to a yyyy/mm/dd format */

	$how = user_date_format();
	$sep = $dateseps[user_date_sep()];

	if ($date_ == null || strlen($date_) == 0)
		return "";

	$date_ = trim($date_);
	$date_ = str_replace($sep, "", $date_);

	if (strlen($date_) == 6)
	{
		if ($how == 0)
		{
			$day = substr($date_,2,2);
			$month = substr($date_,0,2);
			$year = substr($date_,4,2);
		} 
		elseif ($how == 1)
		{
			$day = substr($date_,0,2);
			$month = substr($date_,2,2);
			$year = substr($date_,4,2);
		} 
		else
		{
			$day = substr($date_,4,2);
			$month = substr($date_,2,2);
			$year = substr($date_,0,2);
		}
	}
	elseif (strlen($date_) == 8)
	{
		if ($how == 0)
		{
			$day = substr($date_,2,2);
			$month = substr($date_,0,2);
			$year = substr($date_,4,4);
		} 
		elseif ($how == 1)
		{
			$day = substr($date_,0,2);
			$month = substr($date_,2,2);
			$year = substr($date_,4,4);
		} 
		else
		{
			$day = substr($date_,6,2);
			$month = substr($date_,4,2);
			$year = substr($date_,0,4);
		}
	}

//to modify assumption in 2030
	if ($date_system == 0)
	{
		if ((int)$year < 60)
		{
			$year = "20".$year;
		} 
		elseif ((int)$year > 59 && (int)$year < 100)
		{
			$year = "19".$year;
		}
	}	
	if ((int)$year > 9999)
	{
		return 0;
	}
	if ($date_system == 1)
		list($year, $month, $day) = jalali_to_gregorian($year, $month, $day); 
	else if ($date_system == 2)
		list($year, $month, $day) = islamic_to_gregorian($year, $month, $day); 
	return $year."-".$month."-".$day;
}// end of function

function date1_greater_date2 ($date1, $date2) 
{

/* returns 1 true if date1 is greater than date_ 2 */

	$date1 = date2sql($date1);
	$date2 = date2sql($date2);
	list($year1, $month1, $day1) = explode("-", $date1);
	list($year2, $month2, $day2) = explode("-", $date2);

	if ($year1 > $year2)
	{
		return 1;
	}
	elseif ($year1 == $year2)
	{
		if ($month1 > $month2)
		{
			return 1;
		}
		elseif ($month1 == $month2)
		{
			if ($day1 > $day2)
			{
				return 1;
			}
		}
	}
	return 0;
}


function date_diff ($date1, $date2, $period) 
{

/* expects dates in the format specified in $DefaultDateFormat - period can be one of 'd','w','y','m'
months are assumed to be 30 days and years 365.25 days This only works
provided that both dates are after 1970. Also only works for dates up to the year 2035 ish */

	$date1 = date2sql($date1);
	$date2 = date2sql($date2);
	list($year1, $month1, $day1) = explode("-", $date1);
	list($year2, $month2, $day2) = explode("-", $date2);

	$stamp1 = mktime(0,0,0, (int)$month1, (int)$day1, (int)$year1);
	$stamp2 = mktime(0,0,0, (int)$month2, (int)$day2, (int)$year2);
	$difference = $stamp1 - $stamp2;

/* difference is the number of seconds between each date negative if date_ 2 > date_ 1 */

	switch ($period) 
	{
		case "d":
			return (int)($difference / (24 * 60 * 60));
		case "w":
			return (int)($difference / (24 * 60 * 60 * 7));
		case "m":
			return (int)($difference / (24 * 60 * 60 * 30));
		case "s":
			return $difference;
		case "y":
			return (int)($difference / (24 * 60 * 60 * 365.25));
		default:
			Return 0;
	}
}

function explode_date_to_dmy($date_)
{
	$date = date2sql($date_);
	if ($date == "") 
	{
		$disp = user_date_display();
		echo "<br>Dates must be entered in the format $disp. Sent was $date_<br>";
		exit;
	}
	list($year, $month, $day) = explode("-", $date);
	return array($day, $month, $year);
}

function div($a, $b) 
{
    return (int) ($a / $b);
}
/* Based on convertor to and from Gregorian and Jalali calendars.
   Copyright (C) 2000  Roozbeh Pournader and Mohammad Toossi 
   Released under GNU General Public License */

function gregorian_to_jalali ($g_y, $g_m, $g_d)
{
    $g_days_in_month = array(31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31);
    $j_days_in_month = array(31, 31, 31, 31, 31, 31, 30, 30, 30, 30, 30, 29);

   	$gy = $g_y - 1600;
   	$gm = $g_m - 1;
   	$gd = $g_d - 1;

   	$g_day_no = 365 * $gy + div($gy + 3, 4) - div($gy + 99, 100) + div($gy + 399, 400);

   	for ($i = 0; $i < $gm; ++$i)
      	$g_day_no += $g_days_in_month[$i];
   	if ($gm > 1 && (($gy % 4 == 0 && $gy % 100 != 0) || ($gy % 400 == 0)))
      	/* leap and after Feb */
      	$g_day_no++;
   	$g_day_no += $gd;
   	$j_day_no = $g_day_no - 79;

   	$j_np = div($j_day_no, 12053); /* 12053 = 365*33 + 32/4 */
   	$j_day_no %= 12053;

   	$jy = 979 + 33 * $j_np + 4 * div($j_day_no, 1461); /* 1461 = 365*4 + 4/4 */

   	$j_day_no %= 1461;

   	if ($j_day_no >= 366) 
   	{
      	$jy += div($j_day_no - 1, 365);
      	$j_day_no = ($j_day_no - 1) % 365;
   	}

   	for ($i = 0; $i < 11 && $j_day_no >= $j_days_in_month[$i]; ++$i)
      	$j_day_no -= $j_days_in_month[$i];
   	$jm = $i + 1;
   	$jd = $j_day_no + 1;

   	return array($jy, $jm, $jd);
}

function jalali_to_gregorian($j_y, $j_m, $j_d)
{
    $g_days_in_month = array(31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31);
    $j_days_in_month = array(31, 31, 31, 31, 31, 31, 30, 30, 30, 30, 30, 29);

  	$jy = $j_y - 979;
   	$jm = $j_m - 1;
   	$jd = $j_d - 1;

   	$j_day_no = 365 * $jy + div($jy, 33) * 8 + div($jy % 33 + 3, 4);
   	for ($i = 0; $i < $jm; ++$i)
      	$j_day_no += $j_days_in_month[$i];

   	$j_day_no += $jd;

   	$g_day_no = $j_day_no + 79;

   	$gy = 1600 + 400 * div($g_day_no, 146097); /* 146097 = 365*400 + 400/4 - 400/100 + 400/400 */
   	$g_day_no %= 146097;

   	$leap = true;
   	if ($g_day_no >= 36525) /* 36525 = 365*100 + 100/4 */
   	{
      	$g_day_no--;
      	$gy += 100 * div($g_day_no,  36524); /* 36524 = 365*100 + 100/4 - 100/100 */
      	$g_day_no %= 36524;

      	if ($g_day_no >= 365)
         	$g_day_no++;
      	else
         	$leap = false;
   	}

   	$gy += 4 * div($g_day_no, 1461); /* 1461 = 365*4 + 4/4 */
   	$g_day_no %= 1461;

   	if ($g_day_no >= 366) 
   	{
      	$leap = false;

      	$g_day_no--;
      	$gy += div($g_day_no, 365);
      	$g_day_no %= 365;
   	}

   	for ($i = 0; $g_day_no >= $g_days_in_month[$i] + ($i == 1 && $leap); $i++)
      	$g_day_no -= $g_days_in_month[$i] + ($i == 1 && $leap);
   	$gm = $i + 1;
   	$gd = $g_day_no + 1;

   	return array($gy, $gm, $gd);
}
/* Based on Hidri Date Script 
   Released under GNU General Public License */
function gregorian_to_islamic($g_y, $g_m, $g_d)
{
	$y = $g_y;   
	$m = $g_m;
	$d = $g_d;
	if (($y > 1582) || (($y == 1582) && ($m > 10)) || (($y == 1582) && 
		($m == 10) && ($d > 14))) 
	{
		$jd = (int)((1461 * ($y + 4800 + (int)(($m - 14) / 12)))/ 4) + 
			(int)((367 * ($m - 2 - 12 * ((int)(($m - 14) / 12)))) / 12) - 
			(int)((3 * ((int)(($y + 4900 + (int)(($m - 14) / 12)) / 100))) / 4) + $d - 32075;
	} 
	else 
	{
		$jd = 367 * $y - (int)((7 * ($y + 5001 + (int)(($m - 9) / 7))) / 4) + 
			(int)((275 * $m) / 9) + $d + 1729777;
	}
	$l = $jd - 1948440 + 10632;
	$n = (int)(($l - 1) / 10631);
	$l = $l - 10631 * $n + 354;
	$j = ((int)((10985 - $l) / 5316)) * ((int)((50 * $l) / 17719)) + 
		((int)($l / 5670)) * ((int)((43 * $l) / 15238));
	$l = $l - ((int)((30 - $j) / 15)) * ((int)((17719 * $j) / 50)) - 
		((int)($j / 16)) * ((int)((15238 * $j) / 43)) + 29;
	$m = (int)((24 * $l) / 709);
	$d = $l - (int)((709 * $m) / 24);
	$y = 30 * $n + $j - 30;
	return array($y, $m, $d);
}

function islamic_to_gregorian($i_y, $i_m, $i_d)
{
	$y = $i_y;   
	$m = $i_m;
	$d = $i_d;

	$jd = (int)((11 * $y + 3) / 30) + 354 * $y + 30 * $m - (int)(($m - 1) / 2) + $d + 1948440 - 385;
	if ($jd > 2299160)
	{
		$l = $jd + 68569;
		$n = (int)((4 * $l) / 146097);
		$l = $l - (int)((146097 * $n + 3) / 4);
		$i = (int)((4000 * ($l + 1)) / 1461001);
		$l = $l - (int)((1461 * $i) / 4) + 31;
		$j = (int)((80 * $l) / 2447);
		$d = $l - (int)((2447 * $j) / 80);
		$l= (int)($j / 11);
		$m = $j + 2 - 12 * $l;
		$y = 100 * ($n - 49) + $i + $l;
	} 
	else 
	{
		$j = $jd + 1402;
		$k = (int)(($j - 1) / 1461);
		$l = $j - 1461 * $k;
		$n = (int)(($l - 1) / 365) - (int)($l / 1461);
		$i = $l - 365 * $n + 30;
		$j = (int)((80 * $i) / 2447);
		$d = $i - (int)((2447 * $j) / 80);
		$i = (int)($j / 11);
		$m = $j + 2 - 12 * $i;
		$y = 4 * $k + $n + $i - 4716;
	}
	return array($y, $m, $d);
}
?>