package org.boris.expr.function.excel;
import org.boris.expr.Expr;
import org.boris.expr.ExprError;
import org.boris.expr.ExprException;
import org.boris.expr.ExprMissing;
import org.boris.expr.ExprVariable;
import org.boris.expr.engine.GridReference;
import org.boris.expr.engine.Range;
import org.boris.expr.function.AbstractFunction;
public class OFFSET extends AbstractFunction
{
public Expr evaluate(Expr[] args) throws ExprException {
assertMinArgCount(args, 3);
assertMaxArgCount(args, 5);
Expr r = args[0];
if (!(r instanceof ExprVariable)) {
throw new ExprException("First argument to OFFSET not a reference");
}
ExprVariable ref = (ExprVariable) r;
Range range = (Range) ref.getAnnotation();
if (range == null) {
range = Range.valueOf(ref.getName());
}
if (range == null) {
throw new ExprException("First argument to OFFSET not a reference");
}
GridReference gf = range.getDimension1();
int x = gf.getColumn();
int y = gf.getRow();
int rows = asInteger(args[1], true);
int cols = asInteger(args[2], true);
int height = 1;
int width = 1;
if (args.length > 3) {
Expr h = args[3];
if (!(h instanceof ExprMissing)) {
height = asInteger(h, true);
}
}
if (height < 1) {
return ExprError.VALUE;
}
if (args.length > 4) {
Expr w = args[4];
if (!(w instanceof ExprMissing)) {
width = asInteger(w, true);
}
}
if (width < 1) {
return ExprError.VALUE;
}
GridReference dim1 = new GridReference(x + cols, y + rows);
if (dim1.getColumn() < 1 || dim1.getRow() < 1) {
return ExprError.REF;
}
GridReference dim2 = null;
if (height > 1 || width > 1) {
dim2 = new GridReference(x + cols + width - 1, y + rows + height -
1);
}
Range result = new Range(range.getNamespace(), dim1, dim2);
ExprVariable var = new ExprVariable(ref.getCallback(), result
.toString());
var.setAnnotation(result);
return var;
}
}