//
   //  ========================================================================
   //  Copyright (c) 1995-2012 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.
  //  ========================================================================
  //  Portions of this file adapted for use from Apache Harmony code by written
  //  and contributed to that project by Alexey V. Varlamov under the ASL
  //  ========================================================================
  //
  
  package org.eclipse.jetty.policy.loader;
  
  import java.io.InputStream;
  import java.io.InputStreamReader;
  import java.security.KeyStore;
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.HashSet;
  import java.util.Iterator;
  import java.util.List;
  import java.util.Set;
  
  import org.eclipse.jetty.policy.PolicyBlock;
  import org.eclipse.jetty.policy.PolicyContext;
  import org.eclipse.jetty.policy.PolicyException;
  import org.eclipse.jetty.policy.entry.GrantEntry;
  import org.eclipse.jetty.policy.entry.KeystoreEntry;
  
  /**
   * Load the policies within the stream and resolve into protection domains and permission collections 
   * 
   */
  public class DefaultPolicyLoader
  {
      
      public static Set<PolicyBlock> load( InputStream policyStream, PolicyContext context ) throws PolicyException
      {
          Set<PolicyBlock> policies = new HashSet<PolicyBlock>();
          KeyStore keystore = null;
          
          try
          {
              PolicyFileScanner loader = new PolicyFileScanner();
              
              Collection<GrantEntry> grantEntries = new ArrayList<GrantEntry>();
              List<KeystoreEntry> keystoreEntries = new ArrayList<KeystoreEntry>();
              
              loader.scanStream( new InputStreamReader(policyStream), grantEntries, keystoreEntries );
              
              for ( Iterator<KeystoreEntry> i = keystoreEntries.iterator(); i.hasNext();)
              {
                  KeystoreEntry node = i.next();
                  node.expand( context );
                  
                  keystore = node.toKeyStore();
                  
                  if ( keystore != null )
                  {
                      // we only process the first valid keystore
                      context.setKeystore( keystore );
                      break;
                  }
              }
              
              for ( Iterator<GrantEntry> i = grantEntries.iterator(); i.hasNext(); )
              {            
                  GrantEntry grant = i.next();
                  grant.expand( context );
                  
                  PolicyBlock policy = new PolicyBlock();             
                  
                  policy.setCodeSource( grant.getCodeSource() );
                  policy.setPrincipals( grant.getPrincipals() );
                  policy.setPermissions( grant.getPermissions() );
                  
                  policies.add(policy);
              }      
              
              return policies;
          }
          catch ( Exception e )
          {
              throw new PolicyException( e );
          }
      }
  }