package org.apache.poi.hssf.record.formula.functions;
import java.util.Calendar;
import java.util.GregorianCalendar;
import org.apache.poi.hssf.record.formula.eval.EvaluationException;
import org.apache.poi.hssf.record.formula.eval.NumberEval;
import org.apache.poi.hssf.record.formula.eval.OperandResolver;
import org.apache.poi.hssf.record.formula.eval.ValueEval;
import org.apache.poi.ss.usermodel.DateUtil;
/**
* Calculates the number of days between two dates based on a 360-day year
* (twelve 30-day months), which is used in some accounting calculations. Use
* this function to help compute payments if your accounting system is based on
* twelve 30-day months.
*
* @author PUdalau
*/
public class Days360 extends Var2or3ArgFunction {
public ValueEval evaluate(int srcRowIndex, int srcColumnIndex, ValueEval arg0, ValueEval arg1) {
double result;
try {
double d0 = NumericFunction.singleOperandEvaluate(arg0, srcRowIndex, srcColumnIndex);
double d1 = NumericFunction.singleOperandEvaluate(arg1, srcRowIndex, srcColumnIndex);
result = evaluate(d0, d1, false);
} catch (EvaluationException e) {
return e.getErrorEval();
}
return new NumberEval(result);
}
public ValueEval evaluate(int srcRowIndex, int srcColumnIndex, ValueEval arg0, ValueEval arg1,
ValueEval arg2) {
double result;
try {
double d0 = NumericFunction.singleOperandEvaluate(arg0, srcRowIndex, srcColumnIndex);
double d1 = NumericFunction.singleOperandEvaluate(arg1, srcRowIndex, srcColumnIndex);
ValueEval ve = OperandResolver.getSingleValue(arg2, srcRowIndex, srcColumnIndex);
Boolean method = OperandResolver.coerceValueToBoolean(ve, false);
result = evaluate(d0, d1, method == null ? false : method.booleanValue());
} catch (EvaluationException e) {
return e.getErrorEval();
}
return new NumberEval(result);
}
private static double evaluate(double d0, double d1, boolean method) {
Calendar startingDate = getStartingDate(d0);
Calendar endingDate = getEndingDateAccordingToStartingDate(d1, startingDate);
long startingDay = startingDate.get(Calendar.MONTH) * 30 + startingDate.get(Calendar.DAY_OF_MONTH);
long endingDay = (endingDate.get(Calendar.YEAR) - startingDate.get(Calendar.YEAR)) * 360
+ endingDate.get(Calendar.MONTH) * 30 + endingDate.get(Calendar.DAY_OF_MONTH);
return endingDay - startingDay;
}
private static Calendar getDate(double date) {
Calendar processedDate = new GregorianCalendar();
processedDate.setTime(DateUtil.getJavaDate(date, false));
return processedDate;
}
private static Calendar getStartingDate(double date) {
Calendar startingDate = getDate(date);
if (isLastDayOfMonth(startingDate)) {
startingDate.set(Calendar.DAY_OF_MONTH, 30);
}
return startingDate;
}
private static Calendar getEndingDateAccordingToStartingDate(double date, Calendar startingDate) {
Calendar endingDate = getDate(date);
endingDate.setTime(DateUtil.getJavaDate(date, false));
if (isLastDayOfMonth(endingDate)) {
if (startingDate.get(Calendar.DATE) < 30) {
endingDate = getFirstDayOfNextMonth(endingDate);
}
}
return endingDate;
}
private static boolean isLastDayOfMonth(Calendar date) {
Calendar clone = (Calendar) date.clone();
clone.add(java.util.Calendar.MONTH, 1);
clone.add(java.util.Calendar.DAY_OF_MONTH, -1);
int lastDayOfMonth = clone.get(Calendar.DAY_OF_MONTH);
return date.get(Calendar.DAY_OF_MONTH) == lastDayOfMonth;
}
private static Calendar getFirstDayOfNextMonth(Calendar date) {
Calendar newDate = (Calendar) date.clone();
if (date.get(Calendar.MONTH) < Calendar.DECEMBER) {
newDate.set(Calendar.MONTH, date.get(Calendar.MONTH) + 1);
} else {
newDate.set(Calendar.MONTH, 1);
newDate.set(Calendar.YEAR, date.get(Calendar.YEAR) + 1);
}
newDate.set(Calendar.DATE, 1);
return newDate;
}
}