#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_INTROSPECTION_HLSLSHADERREFLECTOR_H
#define NUCLEX_GRAPHICS_INTROSPECTION_HLSLSHADERREFLECTOR_H

#include "Nuclex/Graphics/Config.h"
#include "Nuclex/Graphics/Introspection/ShaderMetadata.h"
#include "MiniReader.h"

#include <cstddef>
#include <cstdint>

namespace Nuclex { namespace Graphics { namespace Introspection {

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

  /// <summary>Extracts the input layout from a compiled HLSL shader (*.cbo)</summary>
  /// <remarks>
  ///   This could also be achieved via D3DReflect(), but that method requires an extra DLL
  ///   (d3dcompiler_xx.dll) to be shipped and is not available to WinRT / Metro games.
  ///   Doing it by hand is just a little bit more complicated and lets us obtain this
  ///   information in a platform independent manner.
  /// </remarks>
  class HlslShaderReflector {

    /// <summary>Checks whether the provided byte code is from an HLSL shader</summary>
    /// <param name="bytecode">Address at which the compiled shader code is stored</param>
    /// <param name="length">Length of the compiled shader code in bytes</param>
    /// <returns>True if the specified byte code contains a compiled HLSL shader</returns>
    public: static bool IsHlslShader(const std::uint8_t *bytecode, std::size_t length);

    /// <summary>Parses the compiled shader bytecode</summary>
    /// <param name="bytecode">Address at which the compiled shader code is stored</param>
    /// <param name="length">Length of the compiled shader code in bytes</param>
    /// <param name="metadata">
    ///   Receives the metadata describing the shader's inputs and constants
    /// </param>
    public: static void Read(
      const std::uint8_t *bytecode, std::size_t length, ShaderMetadata &metadata
    );

    /// <summary>Parses a chunk of data in the compiled shader bytecode</summary>
    /// <param name="reader">Reader through which the data chunk will be read</param>
    /// <param name="metadata">Metadata container that will be filled</param>
    private: static void readChunk(MiniReader &reader, ShaderMetadata &metadata);

  };

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

}}} // namespace Nuclex::Graphics::Introspection

#endif // NUCLEX_GRAPHICS_INTROSPECTION_HLSLSHADERREFLECTOR_H