/*
 * Copyright (c) 1998-2011 Caucho Technology -- all rights reserved
 *
 * This file is part of Resin(R) Open Source
 *
 * Each copy or derived work must preserve the copyright notice and this
 * notice unmodified.
 *
 * Resin Open Source is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * Resin Open Source 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, or any warranty
 * of NON-INFRINGEMENT.  See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Resin Open Source; if not, write to the
 *   Free SoftwareFoundation, Inc.
 *   59 Temple Place, Suite 330
 *   Boston, MA 02111-1307  USA
 *
 * @author Scott Ferguson
 */

package com.caucho.xsl.fun;

import com.caucho.xpath.Expr;
import com.caucho.xpath.ExprEnvironment;
import com.caucho.xpath.XPathException;
import com.caucho.xpath.XPathFun;
import com.caucho.xpath.pattern.AbstractPattern;

import org.w3c.dom.Node;

import java.text.DecimalFormat;
import java.text.DecimalFormatSymbols;
import java.util.ArrayList;
import java.util.HashMap;

/**
 * The format-number(...) function.
 */
public class FormatNumberFun extends XPathFun {
  private HashMap locales;

  public FormatNumberFun()
  {
    locales = new HashMap();
  }

  /**
   * Add a new xsl:locale
   */
  public void addLocale(String name, DecimalFormatSymbols symbols)
  {
    locales.put(name, symbols);
  }

  public HashMap getLocales()
  {
    return locales;
  }
  /**
   * Evaluate the function.
   *
   * @param pattern The context pattern.
   * @param args The evaluated arguments
   */
  public Object eval(Node node, ExprEnvironment env, 
                     AbstractPattern pattern, ArrayList args)
    throws XPathException
  {
    if (args.size() < 2)
      return null;

    double number = Expr.toDouble(args.get(0));
    String format = Expr.toString(args.get(1));
    String localeName = null;
    if (args.size() > 2)
      localeName = Expr.toString(args.get(2));
    else
      localeName = "*";

    if (format == null)
      return null;

    DecimalFormatSymbols symbols;
    symbols = (DecimalFormatSymbols) locales.get(localeName);

    try {
      DecimalFormat form;

      if (symbols == null)
        form = new DecimalFormat(format);
      else {
        form = new DecimalFormat(format, symbols);
      }
      /*
      formatter = new java.text.DecimalFormat();

          formatter.setDecimalFormatSymbols(dfs);
      
      form.applyLocalizedPattern(format);
      */
    
      return form.format(number);
    } catch (Exception e) {
      throw new XPathException(e);
    }
  }
}