/*
 * Copyright (c) 1998-2012 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 Software Foundation, Inc.
 *   59 Temple Place, Suite 330
 *   Boston, MA 02111-1307  USA
 *
 * @author Scott Ferguson
 */

package com.caucho.rewrite;

import com.caucho.server.rewrite.MatchFilterChain;

import java.util.ArrayList;
import java.util.regex.Pattern;
import java.util.regex.Matcher;

import javax.servlet.DispatcherType;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.ServletException;

abstract public class AbstractRegexpDispatchRule extends AbstractDispatchRule
{
  private Pattern _regexp;

  private ArrayList<RewriteFilter> _filterList
    = new ArrayList<RewriteFilter>();

  private RewriteFilter []_filters = new RewriteFilter[0];

  private ArrayList<RequestPredicate> _predicateList
    = new ArrayList<RequestPredicate>();

  private RequestPredicate []_predicates = new RequestPredicate[0];

  public void setRegexp(Pattern regexp)
  {
    _regexp = regexp;
  }

  public Pattern getRegexp()
  {
    return _regexp;
  }

  @Override
  public boolean isRequest()
  {
    return true;
  }

  @Override
  public boolean isInclude()
  {
    return false;
  }

  @Override
  public boolean isForward()
  {
    return false;
  }

  public boolean isFilter()
  {
    return false;
  }

  public void add(RequestPredicate predicate)
  {
    _predicateList.add(predicate);
    _predicates = new RequestPredicate[_predicateList.size()];
    _predicateList.toArray(_predicates);
  }

  public void add(RewriteFilter filter)
  {
    _filterList.add(filter);
    _filters = new RewriteFilter[_filterList.size()];
    _filterList.toArray(_filters);
  }
  
  public void add(Filter filter)
    throws ServletException
  {
    add(new RewriteFilterAdapter(filter));
  }

  @Override
  public String rewriteUri(String uri, String queryString)
  {
    return uri;
  }
  
  @Override
  public FilterChain map(DispatcherType type,
                         String uri,
                         String queryString,
                         FilterChain next,
                         FilterChain tail)
    throws ServletException
  {
    Matcher matcher = null;

    if (_regexp == null || (matcher = _regexp.matcher(uri)).find()) {
      String target = rewriteTarget(matcher, uri, queryString);

      FilterChain chain = createDispatch(type, uri, queryString, target, tail);

      for (int i = _filters.length - 1; i >= 0; i--) {
        chain = _filters[i].map(uri, queryString, chain);
      }

      if (_predicates.length > 0)
        chain = new MatchFilterChain(_predicates, chain, next);

      return chain;
    }
    else
      return next;
  }

  protected FilterChain createDispatch(DispatcherType type,
                                       String uri,
                                       String queryString,
                                       String target,
                                       FilterChain next)
  {
    return next;
  }

  protected String rewriteTarget(Matcher matcher,
                                 String uri,
                                 String queryString)
  {
    if (queryString == null)
      return uri;
    else if (uri.indexOf('?') >= 0)
      return uri + "&" + queryString;
    else
      return uri + "?" + queryString;
  }

  @Override
  public String toString()
  {
    return getClass().getSimpleName() + "[regexp=" + _regexp + "]";
  }
}
