/*
    * $Id$
    *
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you under the Apache License, Version 2.0 (the
    * "License"); you may not use this file except in compliance
   * with the License.  You may obtain a copy of the License at
   *
   *  http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing,
   * software distributed under the License is distributed on an
   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
   * KIND, either express or implied.  See the License for the
   * specific language governing permissions and limitations
   * under the License.
   */
  
  package gboat2.admin.osgi.action;
  
  import java.io.ByteArrayOutputStream;
  import java.io.PrintStream;
  
  import org.apache.felix.shell.ShellService;
  import org.apache.struts2.convention.annotation.ResultPath;
  import org.apache.struts2.osgi.DefaultBundleAccessor;
  import org.osgi.framework.ServiceReference;
  
  import com.opensymphony.xwork2.Action;
  import com.opensymphony.xwork2.ActionSupport;
  
  /**
   * This action executes commands on the Felix Shell
   * @date 2014-2-26
   * @since 1.0
   */
  @ResultPath("/content")
  //@gboat2.base.core.annotation.Module(name = "shell命令", desc = "执行命令，改变bundle的运行状态")
  public class ShellAction extends ActionSupport {
  
  	private static final long serialVersionUID = 1L;
  
  	private String command;
  
  	private String output;
  
  	@Override
  	public String execute() {
  		System.setProperty("java.protocol.handler.pkgs", "org.ops4j.pax.url.assembly");
  
  		// get service
  		ByteArrayOutputStream outByteStream = new ByteArrayOutputStream();
  		ByteArrayOutputStream errByteStream = new ByteArrayOutputStream();
  		PrintStream outStream = new PrintStream(outByteStream);
  		PrintStream errStream = new PrintStream(errByteStream);
  
  		String outString = null; // 标准信息输出流
  		String errString = null; // 错误信息输出流
  		try {
  		    // 执行命令
  			executeCommand(command, outStream, errStream);
  			outString = outByteStream.toString().trim();
  			errString = errByteStream.toString().trim();
  		} catch (Exception e) {
  			errString = e.getMessage();
  		} finally {
  			outStream.close();
  			errStream.close();
  		}
  
  		output = (errString != null && errString.length() > 0) ? errString : outString;
  
  		return Action.SUCCESS;
  	}
  
  	/**
  	 * 执行 Felix 的 shell 命令
  	 * @param commandLine 命令行的内容，包括命令及其参数
  	 * @param out 标准信息输出流
  	 * @param err 错误信息输出流
  	 * @throws Exception 执行 shell 命令发生错误时，抛出异常
  	 */
  	public void executeCommand(String commandLine, PrintStream out, PrintStream err) throws Exception {
  		ShellService shellService = getShellService();
  		if (shellService != null)
  			shellService.executeCommand(commandLine, out, err);
  		else
  			err.println("Apache Felix Shell service is not installed");
  	}
  
  	/**
  	 * @return Felix 执行 Shell 命令的服务实例
  	 */
  	private ShellService getShellService() {
  		//bundle can be de-activated, so keeping a reference aorund is not a good idea
  		DefaultBundleAccessor bundleAcessor = DefaultBundleAccessor.getInstance();
 		ServiceReference<?> ref = bundleAcessor.getServiceReference(ShellService.class.getName());
 		return (ShellService) bundleAcessor.getService(ref);
 	}
 
     public String getCommand() {
         return command;
     }
 
     public void setCommand(String command) {
         this.command = command;
     }
 
     public String getOutput() {
         return output;
     }
 
 }