#pragma region CPL License
/*
Nuclex Native Framework
Copyright (C) 2002-2013 Nuclex Development Labs

This library is free software; you can redistribute it and/or
modify it under the terms of the IBM Common Public License as
published by the IBM Corporation; either version 1.0 of the
License, or (at your option) any later version.

This library 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
IBM Common Public License for more details.

You should have received a copy of the IBM Common Public
License along with this library
*/
#pragma endregion // CPL License

#ifndef NUCLEX_GRAPHICS_RASTERIZATION_OPTIONS_H
#define NUCLEX_GRAPHICS_RASTERIZATION_OPTIONS_H

#include "../Config.h"
#include "Resource.h"
#include "../Helpers/ConcurrentObserverSet.h"

namespace Nuclex { namespace Graphics { namespace Rasterization {

  // ------------------------------------------------------------------------------------------- //

  /// <summary>Options that can alter the behavior of a rasterizer</summary>
  class Options : Resource {

    #pragma region class Observer

    /// <summary>Observer that can be notified of changes to an options instance</summary>
    public: class Observer : public Resource::Observer {

      /// <summary>Frees all resources owned by the instance</summary>
      public: virtual ~Observer() {}

      /// <summary>Called right before the options are destroyed</summary>
      public: virtual void Destroying() = 0;

      /// <summary>Called when one of the options has changed</summary>
      public: virtual void Changed() = 0;

    };

    #pragma endregion // class Observer

    /// <summary>Initializes a new options container</summary>
    protected: NUCLEX_GRAPHICS_API Options() {}

    /// <summary>Destroys the options container</summary>
    public: NUCLEX_GRAPHICS_API virtual ~Options() {}

    /// <summary>Retrieves the observer attached by the specified owner</summary>
    /// <param name="owner">Owner whose observer will be looked up</param>
    /// <returns>The observer registered by the specified owner or a nullptr</returns>
    public: NUCLEX_GRAPHICS_API Observer *GetObserver(const void *owner) const;

    /// <summary>Attaches an observer to the buffer</summary>
    /// <param name="owner">The observer's owner, used as a unique key</param>
    /// <param name="observer">Observer that will be attached to the buffer</param>
    public: NUCLEX_GRAPHICS_API void AttachObserver(const void *owner, Observer *observer);

    /// <summary>Detaches the specified owner's observer from the buffer</summary>
    /// <param name="owner">Owner whose observer will be detached</param>
    public: NUCLEX_GRAPHICS_API void DetachObserver(const void *owner);

    /// <summary>Notifies all observers that the options are about to be destroyed</summary>
    protected: NUCLEX_GRAPHICS_API void OnDestroying();

    /// <summary>Notifies all observers that the options have been changed</summary>
    protected: NUCLEX_GRAPHICS_API void OnChanged();

    private: Options(const Options &);
    private: Options &operator =(const Options &);

    /// <summary>Observed to changes in the options</summary>
    private: Helpers::ConcurrentObserverSet<Observer> observers;

  };

  // ------------------------------------------------------------------------------------------- //

}}} // namespace Nuclex::Graphics::Rasterization

#endif // NUCLEX_GRAPHICS_RASTERIZATION_OPTIONS_H