model: First set of major API changes and reorganizations

Main motive: change interface in Face class, resulting in need to change forwarding strategy interfaces

Refs #1005 (http://redmine.named-data.net/)
diff --git a/ndn.cxx/ndn-api-face.h b/ndn.cxx/ndn-api-face.h
new file mode 100644
index 0000000..133f29c
--- /dev/null
+++ b/ndn.cxx/ndn-api-face.h
@@ -0,0 +1,169 @@
+/* -*- Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil -*- */
+/*
+ * Copyright (c) 2013 University of California, Los Angeles
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation;
+ *
+ * This program 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 this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * Author: Alexander Afanasyev <alexander.afanasyev@ucla.edu>
+ *         Zhenkai Zhu <zhenkai@cs.ucla.edu>
+ *         Chaoyi Bian <bcy@pku.edu.cn>
+ */
+
+#ifndef NDN_API_FACE_H
+#define NDN_API_FACE_H
+
+#include <boost/exception/all.hpp>
+#include <boost/function.hpp>
+#include <string>
+
+#include <ns3/ptr.h>
+#include <ns3/node.h>
+#include <ns3/random-variable.h>
+#include <ns3/ndn-app.h>
+#include <ns3/ndn-name.h>
+
+#include <ns3/ndnSIM/utils/trie/trie-with-policy.h>
+#include <ns3/ndnSIM/utils/trie/counting-policy.h>
+
+namespace ns3 {
+namespace ndn {
+
+template<class Callback>
+struct FilterEntry : public ns3::SimpleRefCount< FilterEntry<Callback> >
+{
+public:
+  FilterEntry (ns3::Ptr<const ns3::ndn::Name> prefix)
+    : m_prefix (prefix)
+  { }
+  
+  const ns3::ndn::Name &
+  GetPrefix () const
+  { return *m_prefix; }
+
+  void
+  AddCallback (Callback callback)
+  { 
+    m_callback = callback;
+  }
+
+  void
+  ClearCallback ()
+  {
+    m_callback = 0;
+  }
+  
+public:
+  ns3::Ptr<const ns3::ndn::Name> m_prefix; ///< \brief Prefix of the PIT entry
+  Callback m_callback;
+};
+
+
+template<class Callback>
+struct FilterEntryContainer :
+    public ns3::ndn::ndnSIM::trie_with_policy<ns3::ndn::Name,
+                                              ns3::ndn::ndnSIM::smart_pointer_payload_traits< FilterEntry<Callback> >,
+                                              ns3::ndn::ndnSIM::counting_policy_traits>
+{
+};
+
+
+struct OperationException : virtual boost::exception, virtual std::exception { };
+/**
+ * \ingroup sync
+ * @brief A handler for NDN; clients of this code do not need to deal
+ * with NDN API directly
+ */
+class ApiFace
+  // : private ns3::ndn::Face
+{
+public:
+  // typedef boost::function<void (const ndn::Name &, Ptr<Packet>)> DataCallback;
+  // typedef boost::function<void (const ndn::Name &)> InterestCallback;
+  
+  // /**
+  //  * @brief initialize the handler; a lot of things needs to be done. 1) init
+  //  * keystore 2) init keylocator 3) start a thread to hold a loop of ccn_run
+  //  *
+  //  */
+  // ApiFace (Ptr<Node> node);
+  // ~ApiFace ();
+
+  // /**
+  //  * @brief send Interest; need to grab lock m_mutex first
+  //  *
+  //  * @param name the Interest name
+  //  * @param dataCallback the callback function to deal with the returned data
+  //  * @return the return code of ccn_express_interest
+  //  */
+  // // int
+  // // sendInterestForString (const std::string &strInterest, const StringDataCallback &strDataCallback/*, int retry = 0*/);
+
+  // int
+  // sendInterest (const ndn::Name &name, const DataCallback &rawDataCallback/*, int retry = 0*/);
+  
+  // /**
+  //  * @brief set Interest filter (specify what interest you want to receive)
+  //  *
+  //  * @param prefix the prefix of Interest
+  //  * @param interestCallback the callback function to deal with the returned data
+  //  * @return the return code of ccn_set_interest_filter
+  //  */
+  // int
+  // setInterestFilter (const ndn::Name &prefix, const InterestCallback &interestCallback);
+
+  // /**
+  //  * @brief clear Interest filter
+  //  * @param prefix the prefix of Interest
+  //  */
+  // void
+  // clearInterestFilter (const std::string &prefix);
+
+  /**
+   * @brief publish data and put it to local ccn content store; need to grab
+   * lock m_mutex first
+   *
+   * @param name the name for the data object
+   * @param dataBuffer the data to be published
+   * @param freshness the freshness time for the data object
+   * @return code generated by NDN library calls, >0 if success
+   */
+  // int
+  // publishStringData (const std::string &name, const std::string &dataBuffer, int freshness)
+  // {
+  //   return publishRawData (name, dataBuffer.c_str(), dataBuffer.length(), freshness);
+  // }
+
+  // int
+  // publishRawData (const std::string &name, const char *buf, size_t len, int freshness);
+
+private:
+  // // from ndn::App
+  // virtual void
+  // OnInterest (const ns3::Ptr<const ns3::ndn::Interest> &interest, ns3::Ptr<ns3::Packet> packet);
+ 
+  // virtual void
+  // OnContentObject (const ns3::Ptr<const ns3::ndn::ContentObject> &contentObject,
+  //                  ns3::Ptr<ns3::Packet> payload);
+
+private:
+  ns3::UniformVariable m_rand; // nonce generator
+
+  FilterEntryContainer<RawDataCallback> m_dataCallbacks;
+  FilterEntryContainer<InterestCallback> m_interestCallbacks;
+};
+
+}
+}
+
+#endif // NDN_API_HANDLER_H