#include <psemek/gfx/texture.hpp>
#include <optional>

namespace psemek::gfx
{

	static std::optional<float> max_anisotropy_level;

	texture_1d::texture_1d()
	{
		gl::GenTextures(1, &id_);
	}

	texture_1d::texture_1d(GLuint id)
		: id_(id)
	{}

	texture_1d texture_1d::null()
	{
		return texture_1d(0);
	}

	void texture_1d::bind() const
	{
		gl::BindTexture(gl::TEXTURE_1D, id_);
	}

	texture_1d::texture_1d(texture_1d && other)
		: id_(other.id_)
		, width_(other.width_)
	{
		other.id_ = 0;
		other.width_ = 0;
	}

	texture_1d & texture_1d::operator = (texture_1d && other)
	{
		if (this == &other) return *this;

		gl::DeleteTextures(1, &id_);
		id_ = other.id_;
		width_ = other.width_;
		other.id_ = 0;
		other.width_ = 0;

		return *this;
	}

	texture_1d::~texture_1d()
	{
		gl::DeleteTextures(1, &id_);
	}

	void texture_1d::load(GLint internal_format, std::size_t width, GLenum format, GLenum type, const void * data)
	{
		bind();
		gl::TexImage1D(gl::TEXTURE_1D, 0, internal_format, width, 0, format, type, data);

		width_ = width;
	}

	void texture_1d::pixels(GLenum format, GLenum type, void * data) const
	{
		bind();
		gl::GetTexImage(gl::TEXTURE_1D, 0, format, type, data);
	}

	texture_1d texture_1d::from_data(GLint internal_format, std::size_t width, GLenum format, GLenum type, const void * data)
	{
		texture_1d tex;
		tex.load(internal_format, width, format, type, data);
		return tex;
	}

	void texture_1d::generate_mipmap()
	{
		bind();
		gl::GenerateMipmap(gl::TEXTURE_1D);
	}

	void texture_1d::nearest_filter()
	{
		bind();
		gl::TexParameteri(gl::TEXTURE_1D, gl::TEXTURE_MAG_FILTER, gl::NEAREST);
		gl::TexParameteri(gl::TEXTURE_1D, gl::TEXTURE_MIN_FILTER, gl::LINEAR_MIPMAP_LINEAR);
	}

	void texture_1d::linear_filter()
	{
		bind();
		gl::TexParameteri(gl::TEXTURE_1D, gl::TEXTURE_MAG_FILTER, gl::LINEAR);
		gl::TexParameteri(gl::TEXTURE_1D, gl::TEXTURE_MIN_FILTER, gl::LINEAR_MIPMAP_LINEAR);
	}

	void texture_1d::anisotropy()
	{
		if (!gl::exts::var_EXT_texture_filter_anisotropic) return;

		if (!max_anisotropy_level)
		{
			max_anisotropy_level = 0;
			gl::GetFloatv(gl::MAX_TEXTURE_MAX_ANISOTROPY_EXT, &(*max_anisotropy_level));
		}
		gl::TexParameterf(gl::TEXTURE_1D, gl::TEXTURE_MAX_ANISOTROPY_EXT, *max_anisotropy_level);
	}

	void texture_1d::repeat()
	{
		bind();
		gl::TexParameteri(gl::TEXTURE_1D, gl::TEXTURE_WRAP_S, gl::REPEAT);
	}

	void texture_1d::clamp()
	{
		bind();
		gl::TexParameteri(gl::TEXTURE_1D, gl::TEXTURE_WRAP_S, gl::CLAMP_TO_EDGE);
	}

	texture_2d::texture_2d()
	{
		gl::GenTextures(1, &id_);
	}

	texture_2d::texture_2d(GLuint id)
		: id_(id)
	{}

	texture_2d texture_2d::null()
	{
		return texture_2d(0);
	}

	void texture_2d::bind() const
	{
		gl::BindTexture(gl::TEXTURE_2D, id_);
	}

	texture_2d::texture_2d(texture_2d && other)
		: id_(other.id_)
		, width_(other.width_)
		, height_(other.height_)
	{
		other.id_ = 0;
		other.width_ = 0;
		other.height_ = 0;
	}

	texture_2d & texture_2d::operator = (texture_2d && other)
	{
		if (this == &other) return *this;

		gl::DeleteTextures(1, &id_);
		id_ = other.id_;
		width_ = other.width_;
		height_ = other.height_;
		other.id_ = 0;
		other.width_ = 0;
		other.height_ = 0;

		return *this;
	}

	texture_2d::~texture_2d()
	{
		gl::DeleteTextures(1, &id_);
	}

	void texture_2d::load(GLint internal_format, std::size_t width, std::size_t height, GLenum format, GLenum type, const void * data)
	{
		bind();
		gl::TexImage2D(gl::TEXTURE_2D, 0, internal_format, width, height, 0, format, type, data);

		width_ = width;
		height_ = height;
	}

	void texture_2d::pixels(GLenum format, GLenum type, void * data) const
	{
		bind();
		gl::GetTexImage(gl::TEXTURE_2D, 0, format, type, data);
	}

	texture_2d texture_2d::from_data(GLint internal_format, std::size_t width, std::size_t height, GLenum format, GLenum type, const void * data)
	{
		texture_2d tex;
		tex.load(internal_format, width, height, format, type, data);
		return tex;
	}

	void texture_2d::generate_mipmap()
	{
		bind();
		gl::GenerateMipmap(gl::TEXTURE_2D);
	}

	void texture_2d::nearest_filter()
	{
		bind();
		gl::TexParameteri(gl::TEXTURE_2D, gl::TEXTURE_MAG_FILTER, gl::NEAREST);
		gl::TexParameteri(gl::TEXTURE_2D, gl::TEXTURE_MIN_FILTER, gl::LINEAR_MIPMAP_LINEAR);
	}

	void texture_2d::linear_filter()
	{
		bind();
		gl::TexParameteri(gl::TEXTURE_2D, gl::TEXTURE_MAG_FILTER, gl::LINEAR);
		gl::TexParameteri(gl::TEXTURE_2D, gl::TEXTURE_MIN_FILTER, gl::LINEAR_MIPMAP_LINEAR);
	}

	void texture_2d::anisotropy()
	{
		if (!gl::exts::var_EXT_texture_filter_anisotropic) return;

		if (!max_anisotropy_level)
		{
			max_anisotropy_level = 0;
			gl::GetFloatv(gl::MAX_TEXTURE_MAX_ANISOTROPY_EXT, &(*max_anisotropy_level));
		}
		gl::TexParameterf(gl::TEXTURE_2D, gl::TEXTURE_MAX_ANISOTROPY_EXT, *max_anisotropy_level);
	}

	void texture_2d::repeat()
	{
		bind();
		gl::TexParameteri(gl::TEXTURE_2D, gl::TEXTURE_WRAP_S, gl::REPEAT);
		gl::TexParameteri(gl::TEXTURE_2D, gl::TEXTURE_WRAP_T, gl::REPEAT);
	}

	void texture_2d::clamp()
	{
		bind();
		gl::TexParameteri(gl::TEXTURE_2D, gl::TEXTURE_WRAP_S, gl::CLAMP_TO_EDGE);
		gl::TexParameteri(gl::TEXTURE_2D, gl::TEXTURE_WRAP_T, gl::CLAMP_TO_EDGE);
	}

	texture_3d::texture_3d()
	{
		gl::GenTextures(1, &id_);
	}

	texture_3d::texture_3d(GLuint id)
		: id_(id)
	{}

	texture_3d texture_3d::null()
	{
		return texture_3d(0);
	}

	void texture_3d::bind() const
	{
		gl::BindTexture(gl::TEXTURE_3D, id_);
	}

	texture_3d::texture_3d(texture_3d && other)
		: id_(other.id_)
		, width_(other.width_)
		, height_(other.height_)
		, depth_(other.depth_)
	{
		other.id_ = 0;
		other.width_ = 0;
		other.height_ = 0;
		other.depth_ = 0;
	}

	texture_3d & texture_3d::operator = (texture_3d && other)
	{
		if (this == &other) return *this;

		gl::DeleteTextures(1, &id_);
		id_ = other.id_;
		width_ = other.width_;
		height_ = other.height_;
		depth_ = other.depth_;
		other.id_ = 0;
		other.width_ = 0;
		other.height_ = 0;
		other.depth_ = 0;

		return *this;
	}

	texture_3d::~texture_3d()
	{
		gl::DeleteTextures(1, &id_);
	}

	void texture_3d::load(GLint internal_format, std::size_t width, std::size_t height, std::size_t depth, GLenum format, GLenum type, const void * data)
	{
		bind();
		gl::TexImage3D(gl::TEXTURE_3D, 0, internal_format, width, height, depth, 0, format, type, data);

		width_ = width;
		height_ = height;
		depth_ = depth;
	}

	void texture_3d::pixels(GLenum format, GLenum type, void * data) const
	{
		bind();
		gl::GetTexImage(gl::TEXTURE_3D, 0, format, type, data);
	}

	texture_3d texture_3d::from_data(GLint internal_format, std::size_t width, std::size_t height, std::size_t depth, GLenum format, GLenum type, const void * data)
	{
		texture_3d tex;
		tex.load(internal_format, width, height, depth, format, type, data);
		return tex;
	}

	void texture_3d::generate_mipmap()
	{
		bind();
		gl::GenerateMipmap(gl::TEXTURE_3D);
	}

	void texture_3d::nearest_filter()
	{
		bind();
		gl::TexParameteri(gl::TEXTURE_3D, gl::TEXTURE_MAG_FILTER, gl::NEAREST);
		gl::TexParameteri(gl::TEXTURE_3D, gl::TEXTURE_MIN_FILTER, gl::LINEAR_MIPMAP_LINEAR);
	}

	void texture_3d::linear_filter()
	{
		bind();
		gl::TexParameteri(gl::TEXTURE_3D, gl::TEXTURE_MAG_FILTER, gl::LINEAR);
		gl::TexParameteri(gl::TEXTURE_3D, gl::TEXTURE_MIN_FILTER, gl::LINEAR_MIPMAP_LINEAR);
	}

	void texture_3d::anisotropy()
	{
		if (!gl::exts::var_EXT_texture_filter_anisotropic) return;

		if (!max_anisotropy_level)
		{
			max_anisotropy_level = 0;
			gl::GetFloatv(gl::MAX_TEXTURE_MAX_ANISOTROPY_EXT, &(*max_anisotropy_level));
		}
		gl::TexParameterf(gl::TEXTURE_3D, gl::TEXTURE_MAX_ANISOTROPY_EXT, *max_anisotropy_level);
	}

	void texture_3d::repeat()
	{
		bind();
		gl::TexParameteri(gl::TEXTURE_3D, gl::TEXTURE_WRAP_S, gl::REPEAT);
		gl::TexParameteri(gl::TEXTURE_3D, gl::TEXTURE_WRAP_T, gl::REPEAT);
		gl::TexParameteri(gl::TEXTURE_3D, gl::TEXTURE_WRAP_R, gl::REPEAT);
	}

	void texture_3d::clamp()
	{
		bind();
		gl::TexParameteri(gl::TEXTURE_3D, gl::TEXTURE_WRAP_S, gl::CLAMP_TO_EDGE);
		gl::TexParameteri(gl::TEXTURE_3D, gl::TEXTURE_WRAP_T, gl::CLAMP_TO_EDGE);
		gl::TexParameteri(gl::TEXTURE_3D, gl::TEXTURE_WRAP_R, gl::CLAMP_TO_EDGE);
	}

}