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#ifndef _DEFAULTSERVERCHOOSER_H_
#define _DEFAULTSERVERCHOOSER_H_

#include <amps/ampsplusplus.hpp>
#include <amps/ServerChooser.hpp>
#include <vector>

///
/// @file DefaultServerChooser.hpp
/// @brief Provides AMPS::DefaultServerChooser, a simple server
/// chooser that implements basic round-robin failover.
///

namespace AMPS
{

///
/// A server chooser that rotates through multiple URIs, in order.
/// Used by HAClient to pick an initial server and
/// also to pick a server if there is a failure.
///
  class DefaultServerChooser : public ServerChooserImpl
  {
  public:
    ///
    /// Default constructor which initializes an empty DefaultServerChooser.
    DefaultServerChooser() : _current(0) {}

    ///
    /// Returns the current URI.
    ///
    /// \return The current URI or empty string if no server is available.
    ///
    virtual std::string getCurrentURI()
    {
      if (_uris.size() > 0)
      {
        return _uris[_current];
      }
      return std::string();
    }

    ///
    /// Adds the given URI to self's list of URIs
    /// \param uri_ The URI to add to self.
    void add(const std::string& uri_)
    {
      _uris.push_back(uri_);
    }

    ///
    /// Adds the given URIs to self's list of URIs
    /// \param uriContainer_ The URIs to add to self.
    template <class T>
    void addAll(const T& uriContainer_)
    {
      for (typename T::const_iterator i = uriContainer_.begin(); i != uriContainer_.end(); ++i)
      {
        _uris.push_back(*i);
      }
    }

    ///
    /// Removes the given URI from self's list of URIs if found.
    /// For DefaultServerChooser, this method has no effect.
    void remove(const std::string& /*uri_*/)
    {
      //Not permitted in DefaultServerChooser
    }

    ///
    /// Returns the Authenticator instance associated with the current URI.
    ///
    /// \return The DefaultAuthenticator instance
    ///
    virtual Authenticator& getCurrentAuthenticator()
    {
      return DefaultAuthenticator::instance();
    }

    ///
    /// Called by HAClient when an error occurs connecting to the current URI,
    /// and/or when an error occurs logging on.
    /// Advance the current URI to the next one in a list
    /// \param exception_ The exception associated with the failure.
    virtual void reportFailure(const AMPSException& exception_,
                               const ConnectionInfo& /* info_ */)
    {
      if (strcmp(exception_.getClassName(), "DisconnectedException") != 0)
      {
        next();
      }
    }

    ///
    /// Called by HAClient when no servers are available to
    /// provide a more detailed error message in the exception message.
    /// This implementation returns an empty string.
    /// \return The detailed error message.
    virtual std::string getError()
    {
      return std::string();
    }

    ///
    /// Called by the HAClient when successfully connected and logged on to
    /// the current instance. This implementation does nothing.
    virtual void reportSuccess(const ConnectionInfo& /* info_ */)
    {
    }

    ///
    /// Advance the server chooser to the next server in the list, starting
    /// over with the first server when the chooser reaches the end of the list.
    virtual void next()
    {
      if (_uris.size() == 0)
      {
        return;
      }
      _current = (_current + 1) % _uris.size();
    }

    ///
    /// Destroy self.
    ///
    ~DefaultServerChooser() {}

  private:
    std::vector<std::string> _uris;
    size_t _current;
  };

} //namespace AMPS

#endif //_DEFAULTSERVERCHOOSER_H_

