package cz.cuni.amis.pogamut.base.utils.logging.jmx;
   
   import java.util.Map;
   import java.util.logging.Level;
   
   import javax.management.InstanceAlreadyExistsException;
   import javax.management.MBeanRegistrationException;
   import javax.management.MBeanServer;
   import javax.management.MalformedObjectNameException;
  import javax.management.NotCompliantMBeanException;
  import javax.management.ObjectName;
  
  
  import cz.cuni.amis.pogamut.base.utils.exception.PogamutJMXNameException;
  import cz.cuni.amis.pogamut.base.utils.jmx.PogamutJMX;
  import cz.cuni.amis.pogamut.base.utils.logging.ILogCategories;
  import cz.cuni.amis.pogamut.base.utils.logging.LogCategory;
  import cz.cuni.amis.utils.exception.PogamutException;
  
  /**
   * JMX decorator for ILogCategories. Every new log category will implicitly have 
   * handler with JMXLogPublisher attached.
   * 
   * @author Jimmy
   */
  
  public class JMXLogCategories implements ILogCategories, JMXLogCategoriesMBean {	
  	
  	/**
  	 * Wrapped categories we're decorating.
  	 */
  	protected ILogCategories logCategories;
  	
  	/**
  	 * MBean server for the log categories.
  	 */
  	protected MBeanServer mBeanServer;
  	
      /**
       * Id of the MBean.
       */
      protected ObjectName objectName = null;
  
  	/**
  	 * JMXLogCategories differs from LogCategories by implicit handler with JMXLogPublisher in every 
  	 * log category it produces.
  	 * <p><p>
  	 * Can't be instantiated twice for one (JMX Domain,mBeanServer)!
  	 * 
  	 * @param logCategories
  	 * @param mBeanServer
  	 * @param parent
  	 * @throws InstanceAlreadyExistsException raised if instantiated twice for one jmx domain
  	 * @throws MBeanRegistrationException
  	 * @throws NotCompliantMBeanException
  	 * @throws MalformedObjectNameException
  	 * @throws NullPointerException
  	 */
  	public JMXLogCategories(ILogCategories logCategories, MBeanServer mBeanServer, ObjectName parent) throws InstanceAlreadyExistsException, MBeanRegistrationException, NotCompliantMBeanException, MalformedObjectNameException, NullPointerException {
  		this.logCategories = logCategories;
  		this.mBeanServer = mBeanServer;
  		
          objectName = ObjectName.getInstance(getJMXLogCategoriesName(parent));
          mBeanServer.registerMBean(this, objectName);
          for (LogCategory category : getCategories().values()) {
  			category.addHandler(newJMXLogPublisher(category.getName()));
  		}		
  	}
  	
  	/**
  	 * Returns existing category by the name or adds new one.
  	 * <p><p>
  	 * Contains handler with JMXLogPublisher attached.
  	 * <p><p>
  	 * If you wish to add another handler do:
  	 * LogCategory myCategory = categories.getCategory("my log"); // create new category
  	 * myCategory.newHandler(new LogPublisher.ConsolePublisher()); // add new handler with output to the console
  	 * 
  	 * @param name
  	 * @return
  	 */
      @Override
  	public synchronized LogCategory getCategory(String name) {
  		if (hasCategory(name)) {
  			return logCategories.getCategory(name);
  		} else {
  			// creating new category
  			LogCategory newCategory = logCategories.getCategory(name);
  			newCategory.addHandler(newJMXLogPublisher(name));		
  			return newCategory;
  		}
  	}
  	
  	private JMXLogPublisher newJMXLogPublisher(String name) {
          try {
              ObjectName categoryObjName = ObjectName.getInstance(getJMXLogCategoryName(name));
              JMXLogPublisher logPublisher = new JMXLogPublisher(categoryObjName, name);
              mBeanServer.registerMBean(logPublisher, categoryObjName);
              return logPublisher;
         } catch (Exception e) {
         	throw new PogamutException("Can't register JMXLogPublisher with name " + getJMXLogCategoryName(objectName, name) + ".", e, this);
         }
 	}
 
    	@Override
 	public Map<String, LogCategory> getCategories() {
 		return logCategories.getCategories();
 	}
 
 	@Override
 	public String[] getCategoryNames() {
 		return logCategories.getCategoryNames();
 	}
 
 	@Override
 	public String[] getCategoryNamesSorted() {
 		return logCategories.getCategoryNamesSorted();
 	}
 
 	@Override
 	public boolean hasCategory(String name) {		
 		return logCategories.hasCategory(name);
 	}
 
 	@Override
 	public void setLevel(Level newLevel) {
 		logCategories.setLevel(newLevel);
 	}
 
 	@Override
 	public void addLogCategory(String name, LogCategory category) {
 		logCategories.addLogCategory(name, category);
 	}
 	
 	@Override
     public ObjectName getJMXLogCategoryName(String categoryName) throws PogamutJMXNameException {
         return getJMXLogCategoryName(objectName, categoryName);
     }
 
 	public static ObjectName getJMXLogCategoryName(ObjectName parent, String categoryName) throws PogamutJMXNameException {
         return PogamutJMX.getObjectName(parent, categoryName);
 	}
 	
 	@Override
 	public ObjectName getJMXLogCategoriesName() {
 		return objectName;
 	}
 	
 	/**
      * Gets LogCategories's object name given parent's name.
      * @param parent
      * @return
      */
     public static ObjectName getJMXLogCategoriesName(ObjectName parent) throws PogamutJMXNameException{
         return PogamutJMX.getObjectName(parent, PogamutJMX.LOGCATEGORIES_NAME);
     }
 
 }