package com.jclark.xsl.expr;

import com.jclark.xsl.om.*;
import java.util.StringTokenizer;

class NormalizeSpaceFunction extends FunctionOpt1 {
  ConvertibleExpr makeCallExpr(ConvertibleExpr expr) throws ParseException {
    final StringExpr se = expr.makeStringExpr();
    return new ConvertibleStringExpr() {
      public String eval(Node node, ExprContext context) throws XSLException {
	return normalize(se.eval(node, context));
      }
    };
  }

  private static String normalize(String s) {
    StringBuffer buf = new StringBuffer();
    for (StringTokenizer e = new StringTokenizer(s); e.hasMoreElements();) {
      if (buf.length() > 0)
	buf.append(' ');
      buf.append((String)e.nextElement());
    }
    return buf.toString();
  }
}