/// @brief Include to sample cube map textures.
/// @file gli/sampler_cube.hpp

#pragma once

#include "sampler.hpp"
#include "texture_cube.hpp"
#include "core/mipmaps_compute.hpp"
#include "core/convert_func.hpp"

namespace gli
{
	/// Cube map texture sampler
	/// @tparam T Sampler can fetch, write and interpret any texture format but will expose and process the data through type T conversions.
	/// @tparam P Precision in term of ULPs
	template <typename T, qualifier P = defaultp>
	class sampler_cube : public sampler
	{
	private:
		typedef typename detail::interpolate<T>::type interpolate_type;

	public:
		typedef texture_cube texture_type;
		typedef typename texture_type::size_type size_type;
		typedef typename texture_type::extent_type extent_type;
		typedef interpolate_type level_type;
		typedef vec<2, interpolate_type, P> normalized_type;
		typedef vec<4, T, P> texel_type;

		sampler_cube(texture_type const& Texture, wrap Wrap, filter Mip = FILTER_NEAREST, filter Min = FILTER_NEAREST, texel_type const& BorderColor = texel_type(0, 0, 0, 1));

		/// Access the sampler texture object
		texture_type const& operator()() const;

		/// Fetch a texel from the sampler texture
		texel_type texel_fetch(extent_type const& TexelCoord, size_type Face, size_type Level) const;

		/// Write a texel in the sampler texture
		void texel_write(extent_type const& TexelCoord, size_type Face, size_type Level, texel_type const& Texel);

		/// Clear the sampler texture with a uniform texel
		void clear(texel_type const& Texel);

		/// Sample the sampler texture at a specific level
		texel_type texture_lod(normalized_type const& SampleCoord, size_type Face, level_type Level) const;

		/// Generate all the mipmaps of the sampler texture from the texture base level
		void generate_mipmaps(filter Minification);

		/// Generate the mipmaps of the sampler texture from the texture base level to the texture max level included
		void generate_mipmaps(size_type BaseFace, size_type MaxFace, size_type BaseLevel, size_type MaxLevel, filter Minification);

	private:
		typedef typename detail::convert<texture_type, T, P>::func convert_type;
		typedef typename detail::convert<texture_type, T, P>::fetchFunc fetch_type;
		typedef typename detail::convert<texture_type, T, P>::writeFunc write_type;
		typedef typename detail::filterBase<detail::DIMENSION_2D, texture_type, interpolate_type, normalized_type, fetch_type, texel_type>::filterFunc filter_type;

		texture_type Texture;
		convert_type Convert;
		texel_type BorderColor;
		filter_type Filter;
	};

	typedef sampler_cube<float> fsamplerCube;
	typedef sampler_cube<double> dsamplerCube;
	typedef sampler_cube<unsigned int> usamplerCube;
	typedef sampler_cube<int> isamplerCube;

}//namespace gli

#include "./core/sampler_cube.inl"
