/* InitialContext.java --
   Copyright (C) 2000, 2002, 2003, 2004 Free Software Foundation, Inc.

This file is part of GNU Classpath.

GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.

GNU Classpath is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
General Public License for more details.

You should have received a copy of the GNU General Public License
along with GNU Classpath; see the file COPYING.  If not, write to the
Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA.

Linking this library statically or dynamically with other modules is
making a combined work based on this library.  Thus, the terms and
conditions of the GNU General Public License cover the whole
combination.

As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
executable, regardless of the license terms of these independent
modules, and to copy and distribute the resulting executable under
terms of your choice, provided that you also meet, for each linked
independent module, the terms and conditions of the license of that
module.  An independent module is a module which is not derived from
or based on this library.  If you modify this library, you may extend
this exception to your version of the library, but you are not
obligated to do so.  If you do not wish to do so, delete this
exception statement from your version. */


package javax.naming;

import java.applet.Applet;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.util.Enumeration;
import java.util.Hashtable;
import java.util.Properties;

import javax.naming.spi.NamingManager;

public class InitialContext implements Context
{
  protected Context defaultInitCtx;
  protected boolean gotDefault = false;
  protected Hashtable myProps;
  
  public InitialContext (Hashtable environment)
    throws NamingException
  {
    init (environment);
  }
  
  protected InitialContext (boolean lazy)
    throws NamingException
  {
    if (! lazy)
      init (null);
  }
  
  public InitialContext ()
    throws NamingException
  {
    init (null);
  }
 
  /** @since 1.3 */
  protected void init (Hashtable environment)
    throws NamingException
  {
    // FIXME: Is this enough?
    final String[] properties = {
      Context.DNS_URL,
      Context.INITIAL_CONTEXT_FACTORY,
      Context.OBJECT_FACTORIES,
      Context.PROVIDER_URL,
      Context.STATE_FACTORIES,
      Context.URL_PKG_PREFIXES,
    };
      
    // Create myProps, cloning environment if needed.
    if (environment != null)
      myProps = (Hashtable) environment.clone ();
    else
      myProps = new Hashtable ();
      
    Applet napplet = (Applet) myProps.get (Context.APPLET);
      
    for (int i = properties.length - 1; i >= 0; i--)
      {
	Object o = myProps.get (properties[i]);
	  
	if (o == null)
	  {
	    if (napplet != null)
	      o = napplet.getParameter (properties[i]);
	    if (o == null)
	      o = System.getProperty (properties[i]);
	    if (o != null)
	      myProps.put (properties[i], o);
	  }
      }

    try
      {
	Enumeration ep = Thread.currentThread().getContextClassLoader().getResources("jndi.naming");
	while (ep.hasMoreElements ())
	  {
	    URL url = (URL) ep.nextElement ();
	    Properties p = new Properties ();
		    
	    try
	      {
		InputStream is = url.openStream ();
		p.load (is);
		is.close ();
	      }
	    catch (IOException e)
	      {
	      }

	    merge (myProps, p);
	  }
      }
    catch (IOException e)
      {
      }

    String home = System.getProperty("gnu.classpath.home.url");
    if (home != null)
      {
	String url = home + "/jndi.properties";
	Properties p = new Properties ();
	
	try
	  {
	    InputStream is = new URL(url).openStream();
	    p.load (is);
	    is.close ();
	  }
	catch (IOException e)
	  {
	    // Ignore.
	  }

	merge (myProps, p);
      }
  }

  // FIXME: Is this enough?
  private static final String[] colon_list = 
    {
      Context.OBJECT_FACTORIES,
      Context.URL_PKG_PREFIXES,
      Context.STATE_FACTORIES
    };

  private static void merge (Hashtable h1, Hashtable h2)
  {
    Enumeration e2 = h2.keys();
    
    while (e2.hasMoreElements())
      {
	String key2 = (String) e2.nextElement();
	Object value1 = h1.get(key2);
	if (value1 == null)
	  h1.put(key2, h2.get(key2));
	else if (key2.compareTo(colon_list[0]) == 0
		 || key2.compareTo(colon_list[1]) == 0
		 || key2.compareTo(colon_list[2]) == 0
		 || key2.compareTo(colon_list[3]) == 0)
	  {
	    String value2 = (String) h2.get(key2);
	    h1.put(key2, (String) value1 + ":" + value2);
	  }
      }
  }

  protected Context getDefaultInitCtx () throws NamingException
  {
    if (! gotDefault)
      {
	defaultInitCtx = NamingManager.getInitialContext (myProps);
	gotDefault = true;
      }
    return defaultInitCtx;
  }


  protected Context getURLOrDefaultInitCtx (Name name) 
    throws NamingException
  {
    if (name.size () > 0)
      return getURLOrDefaultInitCtx (name.get (0));
    else
      return getDefaultInitCtx ();
  }

  protected Context getURLOrDefaultInitCtx (String name) 
    throws NamingException
  {
    String scheme = null;

    if (NamingManager.hasInitialContextFactoryBuilder())
      return getDefaultInitCtx();
    int colon = name.indexOf(':');
    int slash = name.indexOf('/');
    if (colon > 0 && (slash == -1 || colon < slash))
      scheme = name.substring(0, colon);
    if (scheme != null) 
      {
	Context context = 
	  NamingManager.getURLContext(scheme, myProps);
	if (context != null)
	  return context;
      }
	
    return getDefaultInitCtx();
  }

  public void bind (Name name, Object obj) throws NamingException
  {
    getURLOrDefaultInitCtx (name).bind (name, obj);
  }

  public void bind (String name, Object obj) throws NamingException
  {
    getURLOrDefaultInitCtx (name).bind (name, obj);
  }

  public Object lookup (Name name) throws NamingException
  {
    try
      {
	return getURLOrDefaultInitCtx (name).lookup (name);
      }
    catch (CannotProceedException cpe)
      {
	Context ctx = NamingManager.getContinuationContext (cpe);
	return ctx.lookup (cpe.getRemainingName());
      }
  }

  public Object lookup (String name) throws NamingException
  {
      try
	{
	  return getURLOrDefaultInitCtx (name).lookup (name);
	}
      catch (CannotProceedException cpe)
	{
	  Context ctx = NamingManager.getContinuationContext (cpe);
	  return ctx.lookup (cpe.getRemainingName());
	}
  }

  public void rebind (Name name, Object obj) throws NamingException
  {
    getURLOrDefaultInitCtx (name).rebind (name, obj);
  }

  public void rebind (String name, Object obj) throws NamingException
  {
    getURLOrDefaultInitCtx (name).rebind (name, obj);
  }

  public void unbind (Name name) throws NamingException
  {
    getURLOrDefaultInitCtx (name).unbind (name);
  }

  public void unbind (String name) throws NamingException
  {
    getURLOrDefaultInitCtx (name).unbind (name);
  }

  public void rename (Name oldName, Name newName) throws NamingException
  {
    getURLOrDefaultInitCtx (oldName).rename (oldName, newName);
  }

  public void rename (String oldName, String newName) throws NamingException
  {
    getURLOrDefaultInitCtx (oldName).rename (oldName, newName);
  }

  public NamingEnumeration list (Name name) throws NamingException
  {
    return getURLOrDefaultInitCtx (name).list (name);
  }

  public NamingEnumeration list (String name) throws NamingException
  {
    return getURLOrDefaultInitCtx (name).list (name);
  }

  public NamingEnumeration listBindings (Name name) throws NamingException
  {
    return getURLOrDefaultInitCtx (name).listBindings (name);
  }

  public NamingEnumeration listBindings (String name) throws NamingException
  {
    return getURLOrDefaultInitCtx (name).listBindings (name);
  }

  public void destroySubcontext (Name name) throws NamingException
  {
    getURLOrDefaultInitCtx (name).destroySubcontext (name);
  }

  public void destroySubcontext (String name) throws NamingException
  {
    getURLOrDefaultInitCtx (name).destroySubcontext (name);
  }

  public Context createSubcontext (Name name) throws NamingException
  {
    return getURLOrDefaultInitCtx (name).createSubcontext (name);
  }

  public Context createSubcontext (String name) throws NamingException
  {
    return getURLOrDefaultInitCtx (name).createSubcontext (name);
  }

  public Object lookupLink (Name name) throws NamingException
  {
    return getURLOrDefaultInitCtx (name).lookupLink (name);
  }

  public Object lookupLink (String name) throws NamingException
  {
    return getURLOrDefaultInitCtx (name).lookupLink (name);
  }

  public NameParser getNameParser (Name name) throws NamingException
  {
    return getURLOrDefaultInitCtx (name).getNameParser (name);
  }

  public NameParser getNameParser (String name) throws NamingException
  {
    return getURLOrDefaultInitCtx (name).getNameParser (name);
  }

  public Name composeName (Name name, Name prefix) throws NamingException
  {
    return getURLOrDefaultInitCtx (name).composeName (name, prefix);
  }

  public String composeName (String name, 
			     String prefix) throws NamingException
  {
    return getURLOrDefaultInitCtx (name).composeName (name, prefix);
  }

  public Object addToEnvironment (String propName, 
				  Object propVal) throws NamingException
  {
    return myProps.put (propName, propVal);
  }

  public Object removeFromEnvironment (String propName) throws NamingException
  {
    return myProps.remove (propName);
  }

  public Hashtable getEnvironment () throws NamingException
  {
    return myProps;
  }

  public void close () throws NamingException
  {
    myProps = null;
    defaultInitCtx = null;
  }

  public String getNameInNamespace () throws NamingException
  {
    throw new OperationNotSupportedException ();
  }
}