/*
    * Copyright (c) 2003, Andreas Pataki 
    * All rights reserved.
    *
    * Redistribution and use in source and binary forms, with or without
    * modification, are permitted provided that the following conditions are
    * met:
    *
    * Redistributions of source code must retain the above copyright notice,
   * this list of conditions and the following disclaimer.
   * 
   * Redistributions in binary form must reproduce the above copyright notice,
   * this list of conditions and the following disclaimer in the documentation
   * and/or other materials provided with the distribution.
   * 
   * Neither the name of the author nor the names of its contributors
   * may be used to endorse or promote products derived from this software
   * without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER AND CONTRIBUTORS ``AS
   * IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
   * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
   * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE
   * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
   * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
   * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
   * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
   * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   * POSSIBILITY OF SUCH DAMAGE.
   */
  
  package net.sf.tm.tomcat;
  
  import java.io.BufferedReader;
  import java.io.IOException;
  import java.io.StringReader;
  import java.util.List;
  import java.util.Vector;
  
  import net.sf.tm.ContextManagerException;
  import net.sf.tm.IContextManager;
  import net.sf.tm.WebContext;
  import net.sf.tm.WebContextStatus;
  
  import org.apache.commons.lang.StringUtils;
  
  /***
   * Implementation of a {@link IContextManager} using the Tomcat server manager
   * application.
   * 
   * @author Andreas Pataki
   * @version $Id: TomcatContextManager.java,v 1.6 2004/03/28 16:23:36 apataki Exp $
   */
  public class TomcatContextManager implements IContextManager {
      private TomcatServer server;
  
      /***
       * Default constructor
       */
      public TomcatContextManager(TomcatServer server) {
          this.server = server;
      }
  
      /***
       * @see net.sf.tm.IContextManager#start(java.lang.String)
       */
      public void start(String context) throws ContextManagerException {
          String result;
          try {
              result = server.executeManager("/start?path=" + context);
              testResultForErrors(result);
  
          } catch (IOException e) {
              throw new ContextManagerException(
                  "error executing start context " + context,
                  e);
          }
      }
  
      /***
       * @see net.sf.tm.IContextManager#stop(java.lang.String)
       */
      public void stop(String context) throws ContextManagerException {
          String result;
          try {
              result = server.executeManager("/stop?path=" + context);
              testResultForErrors(result);
          } catch (IOException e) {
              throw new ContextManagerException(
                  "error executing stop context " + context,
                  e);
          }
      }
  
      /***
       * @see net.sf.tm.IContextManager#reload(String)
       */
      public void reload(String context) throws ContextManagerException {
         String result;
         try {
             result = server.executeManager("/reload?path=" + context);
             testResultForErrors(result);
         } catch (IOException e) {
             throw new ContextManagerException(
                 "error executing restart context " + context,
                 e);
         }
     }
 
     /***
      * @see net.sf.tm.IContextManager#getAll()
      */
     public List getAll() throws ContextManagerException {
         String result;
         try {
             result = server.executeManager("/list");
             testResultForErrors(result);
 
             return createContextListFromResult(result);
 
         } catch (IOException e) {
             throw new ContextManagerException("error getting all contexts", e);
         }
 
     }
 
     /***
      * Parses the result of the /list command.
      * 
      * @param result 
      * @return A list of {@link WebContext} objects. If no context exist an 
      *   empty list is returned.
      */
     private List createContextListFromResult(String result)
         throws IOException {
         Vector list = new Vector();
 
         BufferedReader reader = new BufferedReader(new StringReader(result));
         // first line is the OK message, must be skiped
         String line = reader.readLine();
 
         while ((line = reader.readLine()) != null) {
             WebContext context = new WebContext();
             String[] splitLine = StringUtils.split(line, ":");
 
             context.setPath(splitLine[0]);
             context.setActiveSessions(Integer.parseInt(splitLine[2]));
             if (splitLine.length > 3) {
                 // this value is only available since Tomcat 4.1 
                 if (splitLine.length > 4 && splitLine[3].length() == 1) {
                     // on windows the filename may also be split so join it
                     context.setDocPath(splitLine[3] + ":" + splitLine[4]);
                 } else {
                     context.setDocPath(splitLine[3]);
                 }
             }
 
             if ("running".equals(splitLine[1])) {
                 context.setStatus(WebContextStatus.RUNNING);
             } else {
                 context.setStatus(WebContextStatus.STOPPED);
             }
 
             list.add(context);
         }
 
         return list;
     }
 
     /***
      * Checks if the result String is valid. A valid result String starts 
      * with OK in the first line. 
      * 
      * @param result
      * @return
      * @throws IOException
      * @throws ContextManagerException
      */
     private String testResultForErrors(String result)
         throws IOException, ContextManagerException {
         if (result.startsWith("OK")) {
             return null;
         }
 
         // result contains an error message
 
         BufferedReader reader = new BufferedReader(new StringReader(result));
         String errorMsg = reader.readLine();
 
         throw new ContextManagerException(errorMsg);
     }
 
 }