/*
 * AuthManager.h
 *
 * Copyright (C) 2009 Matthias Schiffer <matthias@gamezock.de>
 *
 * This program is free software: you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as published by the
 * Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * 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 Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License along
 * with this program. If not, see <http://www.gnu.org/licenses/>.
 */

#ifndef MAD_COMMON_AUTHMANAGER_H_
#define MAD_COMMON_AUTHMANAGER_H_

#include "export.h"

#include "AuthBackend.h"
#include "AuthContext.h"

#include <Core/Exception.h>

#include <vector>

#include <boost/cstdint.hpp>
#include <boost/noncopyable.hpp>
#include <boost/shared_ptr.hpp>

#include <boost/thread/shared_mutex.hpp>

namespace Mad {
namespace Common {

class Application;

class MAD_COMMON_EXPORT AuthManager : private boost::noncopyable {
  private:
    friend class Application;

    class DenyBackend : public AuthBackend {
      private:
        const static std::vector<std::string> methods;

      protected:
        virtual const std::vector<std::string>& getMethods() const {
          return methods;
        }

        virtual boost::shared_ptr<AuthContext> authenticate(const std::string& /*method*/, const std::string& /*user*/,
            const std::vector<boost::uint8_t>& /*challenge*/, std::vector<boost::uint8_t>& /*response*/,
            boost::shared_ptr<AuthContext> /*context*/) throw(Core::Exception) {
          throw Core::Exception(Core::Exception::NOT_IMPLEMENTED);
        }
    };

    boost::shared_ptr<DenyBackend> denyBackend;

    boost::shared_ptr<AuthBackend> backend;

    boost::shared_mutex mutex;

    AuthManager() : denyBackend(new DenyBackend), backend(denyBackend) {}

  public:
    void registerBackend(boost::shared_ptr<AuthBackend> newBackend);
    void unregisterBackend(boost::shared_ptr<AuthBackend> oldBackend);

    std::vector<std::string> getMethods();

    boost::shared_ptr<AuthContext> authenticate(const std::string &method, const std::string &user, const std::vector<boost::uint8_t> &challenge,
        std::vector<boost::uint8_t> &response, boost::shared_ptr<AuthContext> context = boost::shared_ptr<AuthContext>()) throw(Core::Exception);
};

}
}

#endif /* MAD_COMMON_AUTHMANAGER_H_ */