/*
    * ManualUserGroup.java
    *
    * Created on May 25, 2004, 4:48 PM
    */
   
   package gov.bnl.gums.userGroup;
   
   import java.io.BufferedReader;
  import java.io.FileReader;
  import java.io.InputStreamReader;
  import java.net.URL;
  import java.net.URLConnection;
  import java.security.Security;
  import java.util.ArrayList;
  import java.util.Calendar;
  import java.util.Date;
  import java.util.Iterator;
  import java.util.List;
  import java.util.Properties;
  import java.util.regex.Matcher;
  import java.util.regex.Pattern;
  
  import org.apache.log4j.Logger;
  
  import gov.bnl.gums.configuration.Configuration;
  import gov.bnl.gums.db.ManualUserGroupDB;
  import gov.bnl.gums.FQAN;
  import gov.bnl.gums.GridUser;
  import gov.bnl.gums.RWLock;
  
  /** 
   * A user group that is defined by a list of users stored in some way, allowing
   * to add and remove users. The persistance layer is implemented through an
   * interface, allowing different storage frameworks (i.e. database, LDAP, file)
   * <p>
   * This class will provide also configurable data caching.
   *
   * @author Gabriele Carcassi, Jay Packard
   */
  public class ManualUserGroup extends UserGroup {
      static public String getTypeStatic() {
  		return "manual";
  	}
      
      private Logger log = Logger.getLogger(ManualUserGroup.class);
      private ManualUserGroupDB db;
  	private String persistenceFactory = "";
  	private String membersUri = "";
  	private String nonMembersUri = "";
  	private List patternList = new ArrayList();
  	private boolean needsRefresh = true;
  	private RWLock rWLock = new RWLock();
  	protected Date patternListLastUpdated;
  	protected int secondsBetweenPatternRefresh = 60;
  	protected int adminSecondsBetweenPatternRefresh = 10;
      
      /**
       * Create a new manual user group. This empty constructor is needed by the XML Digestor.
       */
      public ManualUserGroup() {
      	super();
      	
      	Security.addProvider(new com.sun.net.ssl.internal.ssl.Provider());
  		Properties properties = System.getProperties();
  		String handlers = System.getProperty("java.protocol.handler.pkgs");
  		if (handlers == null) {
  		    // nothing specified yet (expected case)
  		    properties.put("java.protocol.handler.pkgs", "com.sun.net.ssl.internal.www.protocol");
  		}
  		else {
  		    // something already there, put ourselves out front
  		    properties.put("java.protocol.handler.pkgs", "com.sun.net.ssl.internal.www.protocol|".concat(handlers));		    
  		}
  
      }
      
      /**
       * Create a new manual user group with a configuration.
       */
      public ManualUserGroup(Configuration configuration) {
      	super(configuration);
      }
      
      /**
       * Create a new manual user group with a configuration and a name.
       */
  	public ManualUserGroup(Configuration configuration, String name) {
  		super(configuration, name);
  	}
      
      public void addMember(GridUser user) {
      	rWLock.getReadLock();
      	try {
  	        getDB().addMember(user);
  	        needsRefresh = true;
      	}
      	catch(Exception e) {
      		log.error(e);
     	}
     	finally {
     		rWLock.releaseLock();
     	}
     }
     
     public UserGroup clone(Configuration configuration) {
     	ManualUserGroup userGroup = new ManualUserGroup(configuration, new String(getName()));
     	userGroup.setDescription(new String(getDescription()));
     	userGroup.setAccess(new String(getAccess()));
     	userGroup.setMembersUri(new String(membersUri));
     	userGroup.setNonMembersUri(new String(nonMembersUri));
     	userGroup.setPersistenceFactory(new String(persistenceFactory));
     	return userGroup;
     }
     
     private ManualUserGroupDB getDB() {
     	if (db==null)
     		db = getConfiguration().getPersistenceFactory(persistenceFactory).retrieveManualUserGroupDB( getName() );
     	return db;
     }
     
     public java.util.List getMemberList() {
         return getDB().retrieveMembers();
     }
 
     public String getMembersUri() {
     	return membersUri;
     }
 
     public String getNonMembersUri() {
     	return nonMembersUri;
     }
     
     /**
      * Setter for property persistenceFactory.
      * 
      * @return persistence factory as string.
      */
     public String getPersistenceFactory() {
         return persistenceFactory;
     }
     
     public String getType() {
 		return "manual";
 	}
     
     public boolean isInGroup(GridUser user) {
     	boolean returnVal = false;
 		
     	try {
     		rWLock.getReadLock();
     		Calendar cal = Calendar.getInstance();
             cal.add(Calendar.SECOND, accessIndex==0 ? -adminSecondsBetweenPatternRefresh : -secondsBetweenPatternRefresh);
         	if (needsRefresh || patternListLastUpdated.before(cal.getTime())) {
         		rWLock.releaseLock();
         		refreshPatternList();
             	rWLock.getReadLock();
         	}
         	
     		Iterator it = patternList.iterator();
 	    	while (it.hasNext()) {
 	    		Pattern p = (Pattern)it.next();
 	    		Matcher m = p.matcher(concatDNFqan(user));
 	    		if (log.isTraceEnabled())
 	    			log.trace("trying to match user "+concatDNFqan(user)+" against "+m.toString());
 	    		if (m.matches()) {
 	    			returnVal = true;
 	    			break;
 	    		}
 	    	}
 		}
 		catch(Exception e) {
 			log.error(e);
 		}
 		finally {
 			rWLock.releaseLock();
 		}
     	
         return returnVal;
     }
     
     public boolean removeMember(GridUser user) {
     	rWLock.getReadLock();
     	boolean value = false;
     	try {
     		value = getDB().removeMember(user);
     		needsRefresh = true;
 		}
 		catch(Exception e) {
 			log.error(e);
 		}
 		finally {
 			rWLock.releaseLock();
 		}
         return value;
     }
     
     /**
      * Setter for property persistenceFactory
      * 
      * @param persistenceFactory
      */
     public void setPersistenceFactory(String persistenceFactory) {
         this.persistenceFactory = persistenceFactory;
     }
     
     public void setMembersUri(String membersUri) {
     	this.membersUri = membersUri;
     }
 
     public void setNonMembersUri(String nonMembersUri) {
     	this.nonMembersUri = nonMembersUri;
     }
 
     public String toString() {
         if (persistenceFactory == null) {
             return "ManualUserGroup: persistenceFactory=null - group='" + getName() + "'";
         } else {
             return "ManualUserGroup: persistenceFactory='" + persistenceFactory + "' - group='" + getName() + "'";
         }
     }
  
     public String toString(String bgColor) {
     	return "<td bgcolor=\""+bgColor+"\"><a href=\"userGroups.jsp?command=edit&name=" + getName() + "\">" + getName() + "</a></td><td bgcolor=\""+bgColor+"\">" + getType() + "</td><td bgcolor=\""+bgColor+"\">&nbsp;</td><td bgcolor=\""+bgColor+"\">&nbsp;</td><td bgcolor=\""+bgColor+"\">&nbsp;</td><td bgcolor=\""+bgColor+"\">&nbsp;</td>";
     }
     
     public String toXML() {
     	return "\t\t<manualUserGroup\n"+
 		"\t\t\tname='"+getName()+"'\n"+
 		"\t\t\taccess='"+accessTypes[accessIndex]+"'\n" +
 		"\t\t\tdescription='"+getDescription()+"'\n"+
 		"\t\t\tpersistenceFactory='"+persistenceFactory+"'\n" +
 		"\t\t\tmembersUri='"+membersUri+"'\n" +
 		"\t\t\tnonMembersUri='"+nonMembersUri+"'/>\n\n";
     }    
     
     public void updateMembers() {
     	rWLock.getReadLock();
     	try {
 	    	if (membersUri.length()>0) {
 	    		BufferedReader in = null;
 	    		if (membersUri.startsWith("http")) {
 	    			URL url = new URL(membersUri);
 	    			URLConnection connection = url.openConnection();
 		    		in = new BufferedReader(new InputStreamReader(connection.getInputStream()));
 	    		}
 	    		else if (membersUri.startsWith("file://")) {
 		    		in = new BufferedReader(new FileReader(membersUri.substring(7)));	    			
 	    		}
 	    		else {
 	    			String message = "Unsupported members URI: " + membersUri;
 	    			log.error(message);
 	    			throw new RuntimeException(message);
 	    		}
 	    		List members = getMemberList();
 	    		String line;
 	    		while ((line = in.readLine()) != null) {
 	    			line = line.trim();
 	    			if (line.length()==0)
 	    				continue;
 	    			String[] elements = line.split(",");
 	    			GridUser user = new GridUser();
 	    			if (elements.length >= 1)
 	    				user.setCertificateDN(elements[0]);
 	    			if (elements.length >= 2)
 	    				user.setVoFQAN(new FQAN(elements[1], false));
 	    			if (!members.contains(user)) {
 	    				log.info("Added user "+user+" to "+getName()+" user group");
 	    				getDB().addMember(user);
 	    			}
 	    		}
 	    		if (in!=null)
 	    			in.close();
 	    	}
 	    } catch (Throwable e) {
 	    	String message = "Couldn't retrieve users from URI " + membersUri + ": ";
 	        log.error(message, e);
 	        throw new RuntimeException(message + ": " + e.getMessage());
 	    } finally {
 	    	rWLock.releaseLock();
 	    }
 	    		
 	    rWLock.getReadLock();
 	    try {
 	    	if (nonMembersUri.length()>0) {
 	    		BufferedReader in;
 	    		if (nonMembersUri.startsWith("http")) {
 	    			URL url = new URL(nonMembersUri);
 	    			URLConnection connection = url.openConnection();
 		    		in = new BufferedReader(new InputStreamReader(connection.getInputStream()));
 	    		}
 	    		else if (nonMembersUri.startsWith("file://")) {
 		    		in = new BufferedReader(new FileReader(nonMembersUri.substring(7)));	    			
 	    		}
 	    		else {
 	    			String message = "Unsupported non-members URI: " + membersUri;
 	    			log.error(message);
 	    			throw new RuntimeException(message);
 	    		}
 	    		List members = getMemberList();
 	    		String line;
 	    		while ((line = in.readLine()) != null) {
 	    			line = line.trim();
 	    			if (line.length()==0)
 	    				continue;
 	    			String[] elements = line.split(",");
 	    			GridUser user = new GridUser();
 	    			if (elements.length >= 1)
 	    				user.setCertificateDN(elements[0]);
 	    			if (elements.length >= 2)
 	    				user.setVoFQAN(new FQAN(elements[1], false));
 	    			if (members.contains(user)) {
 	    				log.info("Removed user "+user+" from "+getName()+" user group");
 	    				getDB().removeMember(user);
 	    			}
 	    		}
 	    		if (in!=null)
 	    			in.close();
 	    	}
 	    } catch (Throwable e) {
 	    	String message = "Couldn't retrieve users from URI " + nonMembersUri + ": ";
 	        log.error(message, e);
 	        throw new RuntimeException(message + ": " + e.getMessage());
 	    } finally {
 	    	rWLock.releaseLock();
 	    }
        	
        	needsRefresh = true;
     }
     
     private String concatDNFqan(GridUser user) {
     	return (user.getCertificateDN()!=null?user.getCertificateDN():"") + "," + (user.getVoFQAN()!=null?user.getVoFQAN().getFqan():"");
     }
     
     private void refreshPatternList() {
     	rWLock.getWriteLock();
     	try {
     		log.trace("refreshed pattern list for usergroup "+getName());
 	 		patternList.clear();
 	 		List members = getDB().retrieveMembers();
 	 		Iterator it = members.iterator();
 	 		while (it.hasNext()) 
 	 		{
 	 			GridUser itUser = (GridUser)it.next();
 	 			Pattern p = Pattern.compile(concatDNFqan(itUser));
 				patternList.add(p);
 	 		}
 			needsRefresh = false;
 			patternListLastUpdated = Calendar.getInstance().getTime();
 		}
 		catch(Exception e) {
 			log.error(e);
 		}
 		finally {
 			rWLock.releaseLock();
 		}
     }
 }