/*

  * Copyright (c) 2003-2011, Simon Brown

  * All rights reserved.

  *

  * Redistribution and use in source and binary forms, with or without

  * modification, are permitted provided that the following conditions are met:

  *

  *   - Redistributions of source code must retain the above copyright

  *     notice, this list of conditions and the following disclaimer.

  *

  *   - Redistributions in binary form must reproduce the above copyright

  *     notice, this list of conditions and the following disclaimer in

  *     the documentation and/or other materials provided with the

  *     distribution.

  *

  *   - Neither the name of Pebble nor the names of its contributors may

  *     be used to endorse or promote products derived from this software

  *     without specific prior written permission.

  *

  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"

  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE

  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR

  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF

  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS

  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN

  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)

  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE

  * POSSIBILITY OF SUCH DAMAGE.

  */

 package net.sourceforge.pebble.security;

 import net.sourceforge.pebble.Configuration;

 import net.sourceforge.pebble.Constants;

 import net.sourceforge.pebble.comparator.PebbleUserDetailsComparator;

 import org.apache.commons.logging.Log;

 import org.apache.commons.logging.LogFactory;

 import org.springframework.context.ApplicationEvent;

 import org.springframework.context.ApplicationListener;

 import org.springframework.context.event.ContextRefreshedEvent;

 import org.springframework.security.authentication.dao.SaltSource;

 import org.springframework.security.authentication.encoding.PasswordEncoder;

 import java.io.*;

 import java.util.*;

 /**

  * Implementation of the SecurityRealm that gets authentication

  * credentials from the blog directory.

  *

  * @author    Simon Brown

  */

 public class DefaultSecurityRealm implements SecurityRealm, ApplicationListener {

   private static final Log log = LogFactory.getLog(DefaultSecurityRealm.class);

   private static final String REALM_DIRECTORY_NAME = "realm";

   protected static final String PASSWORD = "password";

   protected static final String ROLES = "roles";

   protected static final String NAME = "name";

   protected static final String EMAIL_ADDRESS = "emailAddress";

   protected static final String WEBSITE = "website";

   protected static final String PROFILE = "profile";

   protected static final String DETAILS_UPDATEABLE = "detailsUpdateable";

   protected static final String PREFERENCE = "preference.";

   private Configuration configuration;

   private PasswordEncoder passwordEncoder;

   private SaltSource saltSource;

   /** Map of open ids to users, cached in a copy on write map */

   private volatile Map<String, String> openIdMap;

   /**

    * Creates the underlying security realm upon creation, if necessary, and initialises the openIdMap.

    *

    * Note, this used to be an init method for the bean, however, due to a circular dependency between this bean and the

    * Pebble configuration bean, it was possible for the Pebble configuration to have been injected and the init method

    * called before the configuration had the home directory set.  This bug exhibited itself when we upgraded to Spring

    * 3.  So, we initialise on framework start.

    */

   public void onApplicationEvent(ApplicationEvent event) {

     if (event instanceof ContextRefreshedEvent) {

       try {

         File realm = getFileForRealm();

         if (!realm.exists()) {

           realm.mkdirs();

           log.warn("*** Creating default user (username/password)");

           log.warn("*** Don't forget to delete this user in a production deployment!");

           PebbleUserDetails defaultUser = new PebbleUserDetails("username", "password", "Default User", "username@domain.com", "http://www.domain.com", "Default User...", new String[] {Constants.BLOG_OWNER_ROLE, Constants.BLOG_PUBLISHER_ROLE, Constants.BLOG_CONTRIBUTOR_ROLE, Constants.BLOG_ADMIN_ROLE}, new HashMap<String,String>(), true);

           createUser(defaultUser);

         }

       } catch (SecurityRealmException e) {

         log.error("Error while creating security realm", e);

       }

       try {

         // Initialise open id map

         openIdMap = new HashMap<String, String>();

         for (PebbleUserDetails user : getUsers()) {

           for (String openId : user.getOpenIds()) {

             openIdMap.put(openId, user.getUsername());

           }

         }

       } catch (SecurityRealmException e) {

         log.error("Error initialising open ids map", e);

       }

     }

   }

   /**

    * Looks up and returns a collection of all users.

    *

    * @return  a Collection of PebbleUserDetails objects

    */

   public synchronized Collection<PebbleUserDetails> getUsers() throws SecurityRealmException {

     LinkedList<PebbleUserDetails> users = new LinkedList<PebbleUserDetails>();

     File realm = getFileForRealm();

     File files[] = realm.listFiles(new FilenameFilter() {

       /**

        * Tests if a specified file should be included in a file list.

        *

        * @param dir  the directory in which the file was found.

        * @param name the name of the file.

        * @return <code>true</code> if and only if the name should be

        *         included in the file list; <code>false</code> otherwise.

        */

       public boolean accept(File dir, String name) {

         return name.endsWith(".properties");

       }

     });

     for (File file : files) {

       PebbleUserDetails pud = getUser(file.getName().substring(0, file.getName().lastIndexOf(".")));

       if (pud != null) {

         users.add(pud);

       }

     }

     Collections.sort(users, new PebbleUserDetailsComparator());

     return users;

   }

   /**

    * Looks up and returns user details for the given username.

    *

    * @param username the username to find details for

    * @return a PebbleUserDetails instance

    *

    */

   public synchronized PebbleUserDetails getUser(String username) throws SecurityRealmException {

     File user = getFileForUser(username);

     if (!user.exists()) {

       return null;

     }

     try {

       FileInputStream in = new FileInputStream(user);

       Properties props = new Properties();

       props.load(in);

       in.close();

       String password = props.getProperty(PASSWORD);

       String[] roles = props.getProperty(ROLES).split(",");

       String name = props.getProperty(NAME);

       String emailAddress = props.getProperty(EMAIL_ADDRESS);

       String website = props.getProperty(WEBSITE);

       String profile = props.getProperty(PROFILE);

       String detailsUpdateableAsString = props.getProperty(DETAILS_UPDATEABLE);

       boolean detailsUpdateable = true;

       if (detailsUpdateableAsString != null) {

         detailsUpdateable = detailsUpdateableAsString.equalsIgnoreCase("true");

       }

       Map<String,String> preferences = new HashMap<String,String>();

       for (Object key : props.keySet()) {

         String propertyName = (String)key;

         if (propertyName.startsWith(PREFERENCE)) {

           preferences.put(propertyName.substring(PREFERENCE.length()), props.getProperty(propertyName));          

         }

       }

       return new PebbleUserDetails(username, password, name, emailAddress, website, profile, roles, preferences, detailsUpdateable);

     } catch (IOException ioe) {

       throw new SecurityRealmException(ioe);

     }

   }

   public PebbleUserDetails getUserForOpenId(String openId) throws SecurityRealmException {

     String username = openIdMap.get(openId);

     if (username == null) {

       return null;

     } else {

       return getUser(username);

     }

   }

   public synchronized void addOpenIdToUser(PebbleUserDetails pud, String openId) throws SecurityRealmException {

     Collection<String> openIds = new ArrayList<String>(pud.getOpenIds());

     openIds.add(openId);

     pud.setOpenIds(openIds);

     updateUser(pud);

     // Update open id map

     HashMap<String, String> newOpenIdMap = new HashMap<String, String>(openIdMap);

     newOpenIdMap.put(openId, pud.getUsername());

     openIdMap = newOpenIdMap;

   }

   public synchronized void removeOpenIdFromUser(PebbleUserDetails pud, String openId) throws SecurityRealmException {

     // Update open id map

     HashMap<String, String> newOpenIdMap = new HashMap<String, String>(openIdMap);

     newOpenIdMap.remove(openId);

     openIdMap = newOpenIdMap;

     Collection<String> openIds = new ArrayList<String>(pud.getOpenIds());

     openIds.remove(openId);

     pud.setOpenIds(openIds);

     updateUser(pud);

   }

   /**

    * Creates a new user.

    *

    * @param pud   a PebbleUserDetails instance

    */

   public synchronized void createUser(PebbleUserDetails pud) throws SecurityRealmException {

     if (getUser(pud.getUsername()) == null) {

       updateUser(pud, true);

     } else {

       throw new SecurityRealmException("User " + pud.getUsername() + " already exists");

     }

   }

   /**

    * Updates user details.

    *

    * @param pud   a PebbleUserDetails instance

    */

   public synchronized void updateUser(PebbleUserDetails pud) throws SecurityRealmException {

     updateUser(pud, false);

   }

   /**

    * Updates user details, except for the password

    *

    * @param pud   a PebbleUserDetails instance

    */

   private void updateUser(PebbleUserDetails pud, boolean updatePassword) throws SecurityRealmException {

     File user = getFileForUser(pud.getUsername());

     PebbleUserDetails currentDetails = getUser(pud.getUsername());

     Properties props = new Properties();

     if (updatePassword) {

       props.setProperty(DefaultSecurityRealm.PASSWORD, passwordEncoder.encodePassword(pud.getPassword(), saltSource.getSalt(pud)));

     } else {

       props.setProperty(DefaultSecurityRealm.PASSWORD, currentDetails.getPassword());

     }

     props.setProperty(DefaultSecurityRealm.ROLES, pud.getRolesAsString());

     props.setProperty(DefaultSecurityRealm.NAME, pud.getName());

     props.setProperty(DefaultSecurityRealm.EMAIL_ADDRESS, pud.getEmailAddress());

     props.setProperty(DefaultSecurityRealm.WEBSITE, pud.getWebsite());

     props.setProperty(DefaultSecurityRealm.PROFILE, pud.getProfile());

     props.setProperty(DefaultSecurityRealm.DETAILS_UPDATEABLE, "" + pud.isDetailsUpdateable());

     Map<String,String> preferences = pud.getPreferences();

     for (String preference : preferences.keySet()) {

       props.setProperty(DefaultSecurityRealm.PREFERENCE + preference, preferences.get(preference));

     }

     try {

       FileOutputStream out = new FileOutputStream(user);

       props.store(out, "User : " + pud.getUsername());

       out.flush();

       out.close();

     } catch (IOException ioe) {

       throw new SecurityRealmException(ioe);

     }

   }

   /**

    * Changes a user's password.

    *

    * @param username    the username of the user

    * @param password    the new password

    * @throws SecurityRealmException

    */

   public synchronized void changePassword(String username, String password) throws SecurityRealmException {

     PebbleUserDetails pud = getUser(username);

     if (pud != null) {

       pud.setPassword(password);

       updateUser(pud, true);

     }

   }

   /**

    * Removes user details for the given username.

    *

    * @param username    the username of the user to remove

    */

   public synchronized void removeUser(String username) throws SecurityRealmException {

     File user = getFileForUser(username);

     if (user.exists()) {

       user.delete();

     }

     if (user.exists()) {

       throw new SecurityRealmException("User " + username + " could not be deleted");

     }

   }

   protected File getFileForRealm() throws SecurityRealmException {

     // find the directory and file corresponding to the user, of the form

     // ${pebbleContext.dataDirectory}/realm/${username}.properties

     return new File(configuration.getDataDirectory(), DefaultSecurityRealm.REALM_DIRECTORY_NAME);

   }

   protected File getFileForUser(String username) throws SecurityRealmException {

     // find the directory and file corresponding to the user, of the form

     // ${pebbleContext.dataDirectory}/realm/${username}.properties

     return new File(getFileForRealm(), username + ".properties");

   }

   public Configuration getConfiguration() {

     return configuration;

   }

   public void setConfiguration(Configuration configuration) {

     this.configuration = configuration;

   }

   public PasswordEncoder getPasswordEncoder() {

     return passwordEncoder;

   }

   public void setPasswordEncoder(PasswordEncoder passwordEncoder) {

     this.passwordEncoder = passwordEncoder;

   }

   public SaltSource getSaltSource() {

     return saltSource;

   }

   public void setSaltSource(SaltSource saltSource) {

     this.saltSource = saltSource;

   }

 }