/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil -*- */
/**
 * Copyright (C) 2013 Regents of the University of California.
 * @author: Yingdi Yu <yingdi@cs.ucla.edu>
 * @author: Jeff Thompson <jefft0@remap.ucla.edu>
 * See COPYING for copyright and distribution information.
 */

#ifndef NDN_SEC_POLICY_HPP
#define NDN_SEC_POLICY_HPP

#include "../data.hpp"
#include "verifier.hpp"
#include "validation-request.hpp"

namespace ndn {
  
/**
 * A SecPolicy is an abstract base class to represent the policy for verifying data packets.
 * You must create an object of a subclass.
 */
class SecPolicy {
public:
  struct Error : public std::runtime_error { Error(const std::string &what) : std::runtime_error(what) {} };

  /**
   * The virtual destructor.
   */
  virtual
  ~SecPolicy() {}

  /**
   * Check whether the received data packet complies with the verification policy, and get the indication of the next verification step.
   * If there is no next verification step, that imlies policy MUST have already made the verification decision.
   * i.e., either onVerified or onVerifyFailed callback is invoked.
   * @param data The Data object with the signature to check.
   * @param stepCount The number of verification steps that have been done, used to track the verification progress.
   * @param onVerified If the signature is verified, this calls onVerified(data).
   * @param onVerifyFailed If the signature check fails, this calls onVerifyFailed(data).
   * @return the indication of next verification step, null if there is no further step.
   */
  virtual ptr_lib::shared_ptr<ValidationRequest>
  checkVerificationPolicy
    (const ptr_lib::shared_ptr<const Data>& data, int stepCount, const OnVerified& onVerified, const OnVerifyFailed& onVerifyFailed)
  {
    onVerifyFailed();
    return ptr_lib::shared_ptr<ValidationRequest>();
  }

  /**
   * Check whether the received interest packet complies with the verification policy, and get the indication of the next verification step.
   * If there is no next verification step, that implies policy MUST have already made the verification decision.
   * i.e., either onVerified or onVerifyFailed callback is invoked.
   * @param data The Data object with the signature to check.
   * @param stepCount The number of verification steps that have been done, used to track the verification progress.
   * @param onVerified If the signature is verified, this calls onVerified(data).
   * @param onVerifyFailed If the signature check fails, this calls onVerifyFailed(data).
   * @return the indication of next verification step, null if there is no further step.
   */
  virtual ptr_lib::shared_ptr<ValidationRequest>
  checkVerificationPolicy
    (const ptr_lib::shared_ptr<const Interest>& interest, int stepCount, const OnVerified& onVerified, const OnVerifyFailed& onVerifyFailed)
  {
    onVerifyFailed();
    return ptr_lib::shared_ptr<ValidationRequest>();
  }
};

}

#endif