//
   //  ========================================================================
   //  Copyright (c) 1995-2016 Mort Bay Consulting Pty. Ltd.
   //  ------------------------------------------------------------------------
   //  All rights reserved. This program and the accompanying materials
   //  are made available under the terms of the Eclipse Public License v1.0
   //  and Apache License v2.0 which accompanies this distribution.
   //
   //      The Eclipse Public License is available at
  //      http://www.eclipse.org/legal/epl-v10.html
  //
  //      The Apache License v2.0 is available at
  //      http://www.opensource.org/licenses/apache2.0.php
  //
  //  You may elect to redistribute this code under either of these licenses.
  //  ========================================================================
  //
  
  package org.eclipse.jetty.jaas.spi;
  
  import java.io.IOException;
  import java.security.Principal;
  import java.util.ArrayList;
  import java.util.Iterator;
  import java.util.List;
  import java.util.Map;
  
  import javax.security.auth.Subject;
  import javax.security.auth.callback.Callback;
  import javax.security.auth.callback.CallbackHandler;
  import javax.security.auth.callback.NameCallback;
  import javax.security.auth.callback.PasswordCallback;
  import javax.security.auth.callback.UnsupportedCallbackException;
  import javax.security.auth.login.FailedLoginException;
  import javax.security.auth.login.LoginException;
  import javax.security.auth.spi.LoginModule;
  
  import org.eclipse.jetty.jaas.JAASPrincipal;
  import org.eclipse.jetty.jaas.JAASRole;
  import org.eclipse.jetty.jaas.callback.ObjectCallback;
  
  /**
   * AbstractLoginModule
   *
   * Abstract base class for all LoginModules. Subclasses should
   * just need to implement getUserInfo method.
   */
  public abstract class AbstractLoginModule implements LoginModule
  {
      private CallbackHandler callbackHandler;
  
      private boolean authState = false;
      private boolean commitState = false;
      private JAASUserInfo currentUser;
      private Subject subject;
  
      /**
       * JAASUserInfo
       *
       * This class unites the UserInfo data with jaas concepts
       * such as Subject and Principals
       */
      public class JAASUserInfo
      {
          private UserInfo user;
          private Principal principal;
          private List<JAASRole> roles;
  
          public JAASUserInfo (UserInfo u)
          {
              this.user = u;
              this.principal = new JAASPrincipal(u.getUserName());
          }
  
          public String getUserName ()
          {
              return this.user.getUserName();
          }
  
          public Principal getPrincipal()
          {
              return this.principal;
          }
  
   
          public void setJAASInfo (Subject subject)
          {
              subject.getPrincipals().add(this.principal);
              subject.getPrivateCredentials().add(this.user.getCredential());
              subject.getPrincipals().addAll(roles);
          }
  
          public void unsetJAASInfo (Subject subject)
          {
              subject.getPrincipals().remove(this.principal);
              subject.getPrivateCredentials().remove(this.user.getCredential());
              subject.getPrincipals().removeAll(this.roles);
          }
  
         public boolean checkCredential (Object suppliedCredential)
         {
             return this.user.checkCredential(suppliedCredential);
         }
         
         public void fetchRoles() throws Exception
         {
             this.user.fetchRoles();
             this.roles = new ArrayList<JAASRole>();
             if (this.user.getRoleNames() != null)
             {
                 Iterator<String> itor = this.user.getRoleNames().iterator();
                 while (itor.hasNext())
                     this.roles.add(new JAASRole((String)itor.next()));
             }
         }
     }
 
     public Subject getSubject ()
     {
         return this.subject;
     }
 
     public void setSubject (Subject s)
     {
         this.subject = s;
     }
 
     public JAASUserInfo getCurrentUser()
     {
         return this.currentUser;
     }
 
     public void setCurrentUser (JAASUserInfo u)
     {
         this.currentUser = u;
     }
 
     public CallbackHandler getCallbackHandler()
     {
         return this.callbackHandler;
     }
 
     public void setCallbackHandler(CallbackHandler h)
     {
         this.callbackHandler = h;
     }
 
     public boolean isAuthenticated()
     {
         return this.authState;
     }
 
     public boolean isCommitted ()
     {
         return this.commitState;
     }
 
     public void setAuthenticated (boolean authState)
     {
         this.authState = authState;
     }
 
     public void setCommitted (boolean commitState)
     {
         this.commitState = commitState;
     }
     /**
      * @see javax.security.auth.spi.LoginModule#abort()
      * @throws LoginException if unable to abort
      */
     public boolean abort() throws LoginException
     {
         this.currentUser = null;
         return (isAuthenticated() && isCommitted());
     }
 
     /**
      * @see javax.security.auth.spi.LoginModule#commit()
      * @return true if committed, false if not (likely not authenticated)
      * @throws LoginException if unable to commit
      */
     public boolean commit() throws LoginException
     {
         if (!isAuthenticated())
         {
             currentUser = null;
             setCommitted(false);
             return false;
         }
 
         setCommitted(true);
         currentUser.setJAASInfo(subject);
         return true;
     }
 
 
     public Callback[] configureCallbacks ()
     {
 
         Callback[] callbacks = new Callback[3];
         callbacks[0] = new NameCallback("Enter user name");
         callbacks[1] = new ObjectCallback();
         callbacks[2] = new PasswordCallback("Enter password", false); //only used if framework does not support the ObjectCallback
         return callbacks;
     }
     
     
     public boolean isIgnored ()
     {
         return false;
     }
     
     
     public abstract UserInfo getUserInfo (String username) throws Exception;
 
 
 
     /**
      * @see javax.security.auth.spi.LoginModule#login()
      * @return true if is authenticated, false otherwise
      * @throws LoginException if unable to login
      */
     public boolean login() throws LoginException
     {
         try
         {  
             if (isIgnored())
                 return false;
             
             if (callbackHandler == null)
                 throw new LoginException ("No callback handler");
 
             Callback[] callbacks = configureCallbacks();
             callbackHandler.handle(callbacks);
 
             String webUserName = ((NameCallback)callbacks[0]).getName();
             Object webCredential = null;
 
             webCredential = ((ObjectCallback)callbacks[1]).getObject(); //first check if ObjectCallback has the credential
             if (webCredential == null)
                 webCredential = ((PasswordCallback)callbacks[2]).getPassword(); //use standard PasswordCallback
 
             if ((webUserName == null) || (webCredential == null))
             {
                 setAuthenticated(false);
                 throw new FailedLoginException();
             }
 
             UserInfo userInfo = getUserInfo(webUserName);
 
             if (userInfo == null)
             {
                 setAuthenticated(false);
                 throw new FailedLoginException();
             }
 
             currentUser = new JAASUserInfo(userInfo);
             setAuthenticated(currentUser.checkCredential(webCredential));
           
             if (isAuthenticated())
             {
                 currentUser.fetchRoles();
                 return true;
             }
             else
                 throw new FailedLoginException();
         }
         catch (IOException e)
         {
             throw new LoginException (e.toString());
         }
         catch (UnsupportedCallbackException e)
         {
             throw new LoginException (e.toString());
         }
         catch (Exception e)
         {
             if (e instanceof LoginException)
                 throw (LoginException)e;
             throw new LoginException (e.toString());
         }
     }
 
     /**
      * @see javax.security.auth.spi.LoginModule#logout()
      * @return true always
      * @throws LoginException if unable to logout
      */
     public boolean logout() throws LoginException
     {
         this.currentUser.unsetJAASInfo(this.subject);
         return true;
     }
 
     /**
      * @see javax.security.auth.spi.LoginModule#initialize(javax.security.auth.Subject, javax.security.auth.callback.CallbackHandler, java.util.Map, java.util.Map)
      * @param subject the subject
      * @param callbackHandler the callback handler
      * @param sharedState the shared state map
      * @param options the option map
      */
     public void initialize(Subject subject, CallbackHandler callbackHandler,
             Map<String,?> sharedState, Map<String,?> options)
     {
         this.callbackHandler = callbackHandler;
         this.subject = subject;
     }
 
 }