package com.jclark.xsl.expr;

import com.jclark.xsl.om.*;
import java.text.DecimalFormat;

class FormatNumberFunction extends Function2 {
  ConvertibleExpr makeCallExpr(ConvertibleExpr e1, ConvertibleExpr e2) {
    final NumberExpr ne = e1.makeNumberExpr();
    final StringExpr se = e2.makeStringExpr();
    return new ConvertibleStringExpr() {
      public String eval(Node node, ExprContext context) throws XSLException {
	try {
	  return new DecimalFormat(se.eval(node, context)).format(ne.eval(node, context));
	}
	catch (IllegalArgumentException e) {
	  throw new XSLException("invalid format pattern");
	}
      }
    };
  }
}