/* ===========================================================
 
* JFreeChart : a free chart library for the Java(tm) platform
 
* ===========================================================
 
*
 
* (C) Copyright 2000-2017, by Object Refinery Limited and Contributors.
 
*
 
* Project Info:
  
http://www.jfree.org/jfreechart/index.html
 
*
 
* This library is free software; you can redistribute it and/or modify it
 
* under the terms of the GNU Lesser General Public License as published by
 
* the Free Software Foundation; either version 2.1 of the License, or
 
* (at your option) any later version.
 
*
 
* This library 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 Lesser General Public
 
* License for more details.
 
*
 
* You should have received a copy of the GNU Lesser General Public
 
* License along with this library; if not, write to the Free Software
 
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  
02110-1301,
 
* USA.
 
*
 
* [Oracle and Java are registered trademarks of Oracle and/or its affiliates.
 
* Other names may be trademarks of their respective owners.]
 
*
 
*/

package org.jfree.chart.date;

import java.util.Calendar;
import java.util.Date;

/**
 
* Represents a date using an integer, in a similar fashion to the
 
* implementation in Microsoft Excel.
  
The range of dates supported is
 
* 1-Jan-1900 to 31-Dec-9999.
 
* <P>
 
* Be aware that there is a deliberate bug in Excel that recognises the year
 
* 1900 as a leap year when in fact it is not a leap year. You can find more
 
* information on the Microsoft website in article Q181370:
 
* <P>
 
* http://support.microsoft.com/support/kb/articles/Q181/3/70.asp
 
* <P>
 
* Excel uses the convention that 1-Jan-1900 = 1.
  
This class uses the
 
* convention 1-Jan-1900 = 2.
 
* The result is that the day number in this class will be different to the
 
* Excel figure for January and February 1900...but then Excel adds in an extra
 
* day (29-Feb-1900 which does not actually exist!) and from that point forward
 
* the day numbers will match.
 
*/

public class SpreadsheetDate extends SerialDate {

    
/** For serialization. */
    
private static final long serialVersionUID = -2039586705374454461L;
    

    
/**
 

     
* The day number (1-Jan-1900 = 2, 2-Jan-1900 = 3, ..., 31-Dec-9999 =
 

     
* 2958465).
 

     
*/

    
private final int serial;

    
/** The day of the month (1 to 28, 29, 30 or 31 depending on the month). */
    
private final int day;

    
/** The month of the year (1 to 12). */
    
private final int month;

    
/** The year (1900 to 9999). */
    
private final int year;

    
/**
     
* Creates a new date instance.
     
*
     
* @param day
  
the day (in the range 1 to 28/29/30/31).
     
* @param month
  
the month (in the range 1 to 12).
     
* @param year
  
the year (in the range 1900 to 9999).
     
*/

    
public SpreadsheetDate(int day, int month, int year) {

        
if ((year >= 1900) && (year <= 9999)) {
            
this.year = year;
        
}
        
else {
            
throw new IllegalArgumentException(
                
"The 'year' argument must be in range 1900 to 9999.");
        
}

        
if ((month >= MonthConstants.JANUARY)
                
&& (month <= MonthConstants.DECEMBER)) {
            
this.month = month;
        
}
        
else {
            
throw new IllegalArgumentException(
                
"The 'month' argument must be in the range 1 to 12.");
        
}

        
if ((day >= 1) && (day <= SerialDate.lastDayOfMonth(month, year))) {
            
this.day = day;
        
} else {
            
throw new IllegalArgumentException("Invalid 'day' argument.");
        
}

        
// the serial number needs to be synchronised with the day-month-year...
        
this.serial = calcSerial(day, month, year);
    
}

    
/**
     
* Standard constructor - creates a new date object representing the
     
* specified day number (which should be in the range 2 to 2958465.
     
*
     
* @param serial
  
the serial number for the day (range: 2 to 2958465).
     
*/

    
public SpreadsheetDate(int serial) {

        
if ((serial >= SERIAL_LOWER_BOUND) && (serial <= SERIAL_UPPER_BOUND)) {
            
this.serial = serial;
        
}
        
else {
            
throw new IllegalArgumentException(
                
"SpreadsheetDate: Serial must be in range 2 to 2958465.");
        
}

        
// the day-month-year needs to be synchronised with the serial number...
        
// get the year from the serial date
        
final int days = this.serial - SERIAL_LOWER_BOUND;
        
// overestimated because we ignored leap days
        
final int overestimatedYYYY = 1900 + (days / 365);
        
final int leaps = SerialDate.leapYearCount(overestimatedYYYY);
        
final int nonleapdays = days - leaps;
        
// underestimated because we overestimated years
        
int underestimatedYYYY = 1900 + (nonleapdays / 365);

        
if (underestimatedYYYY == overestimatedYYYY) {
            
this.year = underestimatedYYYY;
        
} else {
            
int ss1 = calcSerial(1, 1, underestimatedYYYY);
            
while (ss1 <= this.serial) {
                
underestimatedYYYY = underestimatedYYYY + 1;
                
ss1 = calcSerial(1, 1, underestimatedYYYY);
            
}
            
this.year = underestimatedYYYY - 1;
        
}

        
final int ss2 = calcSerial(1, 1, this.year);

        
int[] daysToEndOfPrecedingMonth
                
= AGGREGATE_DAYS_TO_END_OF_PRECEDING_MONTH;

        
if (isLeapYear(this.year)) {
            
daysToEndOfPrecedingMonth
                    
= LEAP_YEAR_AGGREGATE_DAYS_TO_END_OF_PRECEDING_MONTH;
        
}

        
// get the month from the serial date
        
int mm = 1;
        
int sss = ss2 + daysToEndOfPrecedingMonth[mm] - 1;
        
while (sss < this.serial) {
            
mm = mm + 1;
            
sss = ss2 + daysToEndOfPrecedingMonth[mm] - 1;
        
}
        
this.month = mm - 1;

        
// what's left is d(+1);
        
this.day = this.serial - ss2
                 
- daysToEndOfPrecedingMonth[this.month] + 1;

    
}

    
/**
     
* Returns the serial number for the date, where 1 January 1900 = 2
     
* (this corresponds, almost, to the numbering system used in Microsoft
     
* Excel for Windows and Lotus 1-2-3).
     
*
     
* @return The serial number of this date.
     
*/

    
@Override
    
public int toSerial() {
        
return this.serial;
    
}

    
/**
     
* Returns a {@code java.util.Date} equivalent to this date.
     
*
     
* @return The date.
     
*/

    
@Override
    
public Date toDate() {
        
Calendar calendar = Calendar.getInstance();
        
calendar.set(getYYYY(), getMonth() - 1, getDayOfMonth(), 0, 0, 0);
        
return calendar.getTime();
    
}

    
/**
     
* Returns the year (assume a valid range of 1900 to 9999).
     
*
     
* @return The year.
     
*/

    
@Override
    
public int getYYYY() {
        
return this.year;
    
}

    
/**
     
* Returns the month (January = 1, February = 2, March = 3).
     
*
     
* @return The month of the year.
     
*/

    
@Override
    
public int getMonth() {
        
return this.month;
    
}

    
/**
     
* Returns the day of the month.
     
*
     
* @return The day of the month.
     
*/
    
@Override
    
public int getDayOfMonth() {
        
return this.day;
    
}

    
/**
     
* Returns a code representing the day of the week.
     
* <P>
     
* The codes are defined in the {@link SerialDate} class as:
 

     
* {@code SUNDAY}, {@code MONDAY}, {@code TUESDAY},
 

     
* {@code WEDNESDAY}, {@code THURSDAY}, {@code FRIDAY}, and
 

     
* {@code SATURDAY}.
     
*
     
* @return A code representing the day of the week.
     
*/

    
@Override
    
public int getDayOfWeek() {
        
return (this.serial + 6) % 7 + 1;
    
}

    
/**
     
* Tests the equality of this date with an arbitrary object.
     
* <P>
     
* This method will return true ONLY if the object is an instance of the
     
* {@link SerialDate} base class, and it represents the same day as this
     
* {@link SpreadsheetDate}.
     
*
     
* @param object
  
the object to compare ({@code null} permitted).
     
*
     
* @return A boolean.
     
*/

    
public boolean equals(Object object) {

        
if (object instanceof SerialDate) {
            
SerialDate s = (SerialDate) object;
            
return (s.toSerial() == this.toSerial());
        
} else {
            
return false;
        
}

    
}

    
/**
     
* Returns a hash code for this object instance.
     
*
 

     
* @return A hash code.
     
*/

    
@Override
    
public int hashCode() {
        
return toSerial();
    
}

    
/**
     
* Returns the difference (in days) between this date and the specified
 

     
* 'other' date.
     
*
     
* @param other
  
the date being compared to.
     
*
     
* @return The difference (in days) between this date and the specified
 

     
*
         
'other' date.
     
*/

    
@Override
    
public int compare(SerialDate other) {
        
return this.serial - other.toSerial();
    
}

    
/**
     
* Implements the method required by the Comparable interface.
     
*
 

     
* @param other
  
the other object (usually another SerialDate).
     
*
 

     
* @return A negative integer, zero, or a positive integer as this object
 

     
*
         
is less than, equal to, or greater than the specified object.
     
*/

    
@Override
    
public int compareTo(Object other) {
        
return compare((SerialDate) other);
    

    
}
    

    
/**
     
* Returns true if this SerialDate represents the same date as the
     
* specified SerialDate.
     
*
     
* @param other
  
the date being compared to.
     
*
     
* @return {@code true} if this SerialDate represents the same date as
     
*
         
the specified SerialDate.
     
*/

    
@Override
    
public boolean isOn(SerialDate other) {
        
return (this.serial == other.toSerial());
    
}

    
/**
     
* Returns true if this SerialDate represents an earlier date compared to
     
* the specified SerialDate.
     
*
     
* @param other
  
the date being compared to.
     
*
     
* @return {@code true} if this SerialDate represents an earlier date
     
*
         
compared to the specified SerialDate.
     
*/

    
@Override
    
public boolean isBefore(SerialDate other) {
        
return (this.serial < other.toSerial());
    
}

    
/**
     
* Returns true if this SerialDate represents the same date as the
     
* specified SerialDate.
     
*
     
* @param other
  
the date being compared to.
     
*
     
* @return {@code true} if this SerialDate represents the same date
     
*
         
as the specified SerialDate.
     
*/

    
public boolean isOnOrBefore(SerialDate other) {
        
return (this.serial <= other.toSerial());
    
}

    
/**
     
* Returns true if this SerialDate represents the same date as the
     
* specified SerialDate.
     
*
     
* @param other
  
the date being compared to.
     
*
     
* @return {@code true} if this SerialDate represents the same date
     
*
         
as the specified SerialDate.
     
*/

    
@Override
    
public boolean isAfter(SerialDate other) {
        
return (this.serial > other.toSerial());
    
}

    
/**
     
* Returns true if this SerialDate represents the same date as the
     
* specified SerialDate.
     
*
     
* @param other
  
the date being compared to.
     
*
     
* @return {@code true} if this SerialDate represents the same date as
     
*
         
the specified SerialDate.
     
*/

    
@Override
    
public boolean isOnOrAfter(SerialDate other) {
        
return (this.serial >= other.toSerial());
    
}

    
/**
     
* Returns {@code true} if this {@link SerialDate} is within the
 

     
* specified range (INCLUSIVE).
  
The date order of d1 and d2 is not
 

     
* important.
     
*
     
* @param d1
  
a boundary date for the range.
     
* @param d2
  
the other boundary date for the range.
     
*
     
* @return A boolean.
     
*/

    
@Override
    
public boolean isInRange(SerialDate d1, SerialDate d2) {
        
return isInRange(d1, d2, SerialDate.INCLUDE_BOTH);
    
}

    
/**
     
* Returns true if this SerialDate is within the specified range (caller
     
* specifies whether or not the end-points are included).
  
The order of d1
     
* and d2 is not important.
     
*
     
* @param d1
  
one boundary date for the range.
     
* @param d2
  
a second boundary date for the range.
     
* @param include
  
a code that controls whether or not the start and end
 

     
*
                 
dates are included in the range.
     
*
     
* @return {@code true} if this SerialDate is within the specified
 

     
*
         
range.
     
*/

    
@Override
    
public boolean isInRange(SerialDate d1, SerialDate d2, int include) {
        
int s1 = d1.toSerial();
        
int s2 = d2.toSerial();
        
int start = Math.min(s1, s2);
        
int end = Math.max(s1, s2);
        

        
int s = toSerial();
        
if (include == SerialDate.INCLUDE_BOTH) {
            
return (s >= start && s <= end);
        
}
        
else if (include == SerialDate.INCLUDE_FIRST) {
            
return (s >= start && s < end);
            

        
}
        
else if (include == SerialDate.INCLUDE_SECOND) {
            
return (s > start && s <= end);
            

        
}
        
else {
            
return (s > start && s < end);
            

        
}
    

    
}

    
/**
     
* Calculate the serial number from the day, month and year.
     
* <P>
     
* 1-Jan-1900 = 2.
     
*
     
* @param d
  
the day.
     
* @param m
  
the month.
     
* @param y
  
the year.
     
*
     
* @return the serial number from the day, month and year.
     
*/

    
private int calcSerial(int d, int m, int y) {
        
int yy = ((y - 1900) * 365) + SerialDate.leapYearCount(y - 1);
        
int mm = SerialDate.AGGREGATE_DAYS_TO_END_OF_PRECEDING_MONTH[m];
        
if (m > MonthConstants.FEBRUARY) {
            
if (SerialDate.isLeapYear(y)) {
                
mm = mm + 1;
            
}
        
}
        
int dd = d;
        
return yy + mm + dd + 1;
    
}

}