/*
    *
    * 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 org.apache.hadoop.hbase.rest.model;
  
  import java.io.IOException;
  import java.io.Serializable;
  
  import javax.servlet.ServletContext;
  import javax.xml.bind.annotation.XmlAttribute;
  import javax.xml.bind.annotation.XmlRootElement;
  
  import org.apache.hadoop.hbase.classification.InterfaceAudience;
  import org.apache.hadoop.hbase.protobuf.ProtobufUtil;
  import org.apache.hadoop.hbase.rest.ProtobufMessageHandler;
  import org.apache.hadoop.hbase.rest.RESTServlet;
  import org.apache.hadoop.hbase.rest.protobuf.generated.VersionMessage.Version;
  
  import com.sun.jersey.spi.container.servlet.ServletContainer;
  
  /**
   * A representation of the collection of versions of the REST gateway software
   * components.
   * <ul>
   * <li>restVersion: REST gateway revision</li>
   * <li>jvmVersion: the JVM vendor and version information</li>
   * <li>osVersion: the OS type, version, and hardware architecture</li>
   * <li>serverVersion: the name and version of the servlet container</li>
   * <li>jerseyVersion: the version of the embedded Jersey framework</li>
   * </ul>
   */
  @XmlRootElement(name="Version")
  @InterfaceAudience.Private
  public class VersionModel implements Serializable, ProtobufMessageHandler {
  
    private static final long serialVersionUID = 1L;
  
    private String restVersion;
    private String jvmVersion;
    private String osVersion;
    private String serverVersion;
    private String jerseyVersion;
  
    /**
     * Default constructor. Do not use.
     */
    public VersionModel() {}
    
    /**
     * Constructor
     * @param context the servlet context
     */
    public VersionModel(ServletContext context) {
      restVersion = RESTServlet.VERSION_STRING;
      jvmVersion = System.getProperty("java.vm.vendor") + ' ' +
        System.getProperty("java.version") + '-' +
        System.getProperty("java.vm.version");
      osVersion = System.getProperty("os.name") + ' ' +
        System.getProperty("os.version") + ' ' +
        System.getProperty("os.arch");
      serverVersion = context.getServerInfo();
      jerseyVersion = ServletContainer.class.getPackage()
        .getImplementationVersion();
    }
  
    /**
     * @return the REST gateway version
     */
    @XmlAttribute(name="REST")
    public String getRESTVersion() {
      return restVersion;
    }
  
    /**
     * @return the JVM vendor and version
     */
    @XmlAttribute(name="JVM")
    public String getJVMVersion() {
      return jvmVersion;
    }
  
    /**
     * @return the OS name, version, and hardware architecture
    */
   @XmlAttribute(name="OS")
   public String getOSVersion() {
     return osVersion;
   }
 
   /**
    * @return the servlet container version
    */
   @XmlAttribute(name="Server")
   public String getServerVersion() {
     return serverVersion;
   }
 
   /**
    * @return the version of the embedded Jersey framework
    */
   @XmlAttribute(name="Jersey")
   public String getJerseyVersion() {
     return jerseyVersion;
   }
 
   /**
    * @param version the REST gateway version string
    */
   public void setRESTVersion(String version) {
     this.restVersion = version;
   }
 
   /**
    * @param version the OS version string
    */
   public void setOSVersion(String version) {
     this.osVersion = version;
   }
 
   /**
    * @param version the JVM version string
    */
   public void setJVMVersion(String version) {
     this.jvmVersion = version;
   }
 
   /**
    * @param version the servlet container version string
    */
   public void setServerVersion(String version) {
     this.serverVersion = version;
   }
 
   /**
    * @param version the Jersey framework version string
    */
   public void setJerseyVersion(String version) {
     this.jerseyVersion = version;
   }
 
   /* (non-Javadoc)
    * @see java.lang.Object#toString()
    */
   @Override
   public String toString() {
     StringBuilder sb = new StringBuilder();
     sb.append("rest ");
     sb.append(restVersion);
     sb.append(" [JVM: ");
     sb.append(jvmVersion);
     sb.append("] [OS: ");
     sb.append(osVersion);
     sb.append("] [Server: ");
     sb.append(serverVersion);
     sb.append("] [Jersey: ");
     sb.append(jerseyVersion);
     sb.append("]\n");
     return sb.toString();
   }
 
   @Override
   public byte[] createProtobufOutput() {
     Version.Builder builder = Version.newBuilder();
     builder.setRestVersion(restVersion);
     builder.setJvmVersion(jvmVersion);
     builder.setOsVersion(osVersion);
     builder.setServerVersion(serverVersion);
     builder.setJerseyVersion(jerseyVersion);
     return builder.build().toByteArray();
   }
 
   @Override
   public ProtobufMessageHandler getObjectFromMessage(byte[] message)
       throws IOException {
     Version.Builder builder = Version.newBuilder();
     ProtobufUtil.mergeFrom(builder, message);
     if (builder.hasRestVersion()) {
       restVersion = builder.getRestVersion();
     }
     if (builder.hasJvmVersion()) {
       jvmVersion = builder.getJvmVersion();
     }
     if (builder.hasOsVersion()) {
       osVersion = builder.getOsVersion();
     }
     if (builder.hasServerVersion()) {
       serverVersion = builder.getServerVersion();
     }
     if (builder.hasJerseyVersion()) {
       jerseyVersion = builder.getJerseyVersion();
     }
     return this;
   }
 }