/*
 * Copyright (C) 2023  Christopher J. Howard
 *
 * This file is part of Antkeeper source code.
 *
 * Antkeeper source code is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Antkeeper source code 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
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Antkeeper source code.  If not, see <http://www.gnu.org/licenses/>.
 */

#ifndef ANTKEEPER_GL_GL_SHADER_VARIABLES_HPP
#define ANTKEEPER_GL_GL_SHADER_VARIABLES_HPP

#include <engine/gl/shader-variable.hpp>
#include <glad/gl.h>
#include <vector>

namespace gl {

/**
 * Boolean shader variable implementation using OpenGL.
 */
class gl_shader_bool: public shader_variable
{
public:
	gl_shader_bool(std::size_t size, GLint gl_uniform_location);
	
	[[nodiscard]] inline constexpr shader_variable_type type() const noexcept override
	{
		return shader_variable_type::bvec1;
	}
	
	void update(bool value) const noexcept override;
	void update(bool value, std::size_t index) const override;
	void update(std::span<const bool> values, std::size_t index = 0) const override;
	
private:
	GLint gl_uniform_location;
	mutable std::vector<GLint> ivalues;
};

/**
 * 2-dimensional boolean vector shader variable implementation using OpenGL.
 */
class gl_shader_bvec2: public shader_variable
{
public:
	gl_shader_bvec2(std::size_t size, GLint gl_uniform_location);
	
	[[nodiscard]] inline constexpr shader_variable_type type() const noexcept override
	{
		return shader_variable_type::bvec2;
	}
	
	void update(const math::bvec2& value) const noexcept override;
	void update(const math::bvec2& value, std::size_t index) const override;
	void update(std::span<const math::bvec2> values, std::size_t index = 0) const override;
	
private:
	GLint gl_uniform_location;
	mutable std::vector<GLint> ivalues;
};

/**
 * 3-dimensional boolean vector shader variable implementation using OpenGL.
 */
class gl_shader_bvec3: public shader_variable
{
public:
	gl_shader_bvec3(std::size_t size, GLint gl_uniform_location);
	
	[[nodiscard]] inline constexpr shader_variable_type type() const noexcept override
	{
		return shader_variable_type::bvec3;
	}
	
	void update(const math::bvec3& value) const noexcept override;
	void update(const math::bvec3& value, std::size_t index) const override;
	void update(std::span<const math::bvec3> values, std::size_t index = 0) const override;
	
private:
	GLint gl_uniform_location;
	mutable std::vector<GLint> ivalues;
};

/**
 * 4-dimensional boolean vector shader variable implementation using OpenGL.
 */
class gl_shader_bvec4: public shader_variable
{
public:
	gl_shader_bvec4(std::size_t size, GLint gl_uniform_location);
	
	[[nodiscard]] inline constexpr shader_variable_type type() const noexcept override
	{
		return shader_variable_type::bvec4;
	}
	
	void update(const math::bvec4& value) const noexcept override;
	void update(const math::bvec4& value, std::size_t index) const override;
	void update(std::span<const math::bvec4> values, std::size_t index = 0) const override;
	
private:
	GLint gl_uniform_location;
	mutable std::vector<GLint> ivalues;
};

/**
 * Signed integer shader variable implementation using OpenGL.
 */
class gl_shader_int: public shader_variable
{
public:
	gl_shader_int(std::size_t size, GLint gl_uniform_location);
	
	[[nodiscard]] inline constexpr shader_variable_type type() const noexcept override
	{
		return shader_variable_type::ivec1;
	}
	
	void update(int value) const noexcept override;
	void update(int value, std::size_t index) const override;
	void update(std::span<const int> values, std::size_t index = 0) const override;
	
private:
	GLint gl_uniform_location;
};

/**
 * 2-dimensional signed integer vector shader variable implementation using OpenGL.
 */
class gl_shader_ivec2: public shader_variable
{
public:
	gl_shader_ivec2(std::size_t size, GLint gl_uniform_location);
	
	[[nodiscard]] inline constexpr shader_variable_type type() const noexcept override
	{
		return shader_variable_type::ivec2;
	}
	
	void update(const math::ivec2& value) const noexcept override;
	void update(const math::ivec2& value, std::size_t index) const override;
	void update(std::span<const math::ivec2> values, std::size_t index = 0) const override;
	
private:
	GLint gl_uniform_location;
};

/**
 * 3-dimensional signed integer vector shader variable implementation using OpenGL.
 */
class gl_shader_ivec3: public shader_variable
{
public:
	gl_shader_ivec3(std::size_t size, GLint gl_uniform_location);
	
	[[nodiscard]] inline constexpr shader_variable_type type() const noexcept override
	{
		return shader_variable_type::ivec3;
	}
	
	void update(const math::ivec3& value) const noexcept override;
	void update(const math::ivec3& value, std::size_t index) const override;
	void update(std::span<const math::ivec3> values, std::size_t index = 0) const override;
	
private:
	GLint gl_uniform_location;
};

/**
 * 4-dimensional signed integer vector shader variable implementation using OpenGL.
 */
class gl_shader_ivec4: public shader_variable
{
public:
	gl_shader_ivec4(std::size_t size, GLint gl_uniform_location);
	
	[[nodiscard]] inline constexpr shader_variable_type type() const noexcept override
	{
		return shader_variable_type::ivec4;
	}
	
	void update(const math::ivec4& value) const noexcept override;
	void update(const math::ivec4& value, std::size_t index) const override;
	void update(std::span<const math::ivec4> values, std::size_t index = 0) const override;
	
private:
	GLint gl_uniform_location;
};

/**
 * Unsigned integer shader variable implementation using OpenGL.
 */
class gl_shader_uint: public shader_variable
{
public:
	gl_shader_uint(std::size_t size, GLint gl_uniform_location);
	
	[[nodiscard]] inline constexpr shader_variable_type type() const noexcept override
	{
		return shader_variable_type::uvec1;
	}
	
	void update(unsigned int value) const noexcept override;
	void update(unsigned int value, std::size_t index) const override;
	void update(std::span<const unsigned int> values, std::size_t index = 0) const override;
	
private:
	GLint gl_uniform_location;
};

/**
 * 2-dimensional unsigned integer vector shader variable implementation using OpenGL.
 */
class gl_shader_uvec2: public shader_variable
{
public:
	gl_shader_uvec2(std::size_t size, GLint gl_uniform_location);
	
	[[nodiscard]] inline constexpr shader_variable_type type() const noexcept override
	{
		return shader_variable_type::uvec2;
	}
	
	void update(const math::uvec2& value) const noexcept override;
	void update(const math::uvec2& value, std::size_t index) const override;
	void update(std::span<const math::uvec2> values, std::size_t index = 0) const override;
	
private:
	GLint gl_uniform_location;
};

/**
 * 3-dimensional unsigned integer vector shader variable implementation using OpenGL.
 */
class gl_shader_uvec3: public shader_variable
{
public:
	gl_shader_uvec3(std::size_t size, GLint gl_uniform_location);
	
	[[nodiscard]] inline constexpr shader_variable_type type() const noexcept override
	{
		return shader_variable_type::uvec3;
	}
	
	void update(const math::uvec3& value) const noexcept override;
	void update(const math::uvec3& value, std::size_t index) const override;
	void update(std::span<const math::uvec3> values, std::size_t index = 0) const override;
	
private:
	GLint gl_uniform_location;
};

/**
 * 4-dimensional unsigned integer vector shader variable implementation using OpenGL.
 */
class gl_shader_uvec4: public shader_variable
{
public:
	gl_shader_uvec4(std::size_t size, GLint gl_uniform_location);
	
	[[nodiscard]] inline constexpr shader_variable_type type() const noexcept override
	{
		return shader_variable_type::uvec4;
	}
	
	void update(const math::uvec4& value) const noexcept override;
	void update(const math::uvec4& value, std::size_t index) const override;
	void update(std::span<const math::uvec4> values, std::size_t index = 0) const override;
	
private:
	GLint gl_uniform_location;
};

/**
 * Floating-point shader variable implementation using OpenGL.
 */
class gl_shader_float: public shader_variable
{
public:
	gl_shader_float(std::size_t size, GLint gl_uniform_location);
	
	[[nodiscard]] inline constexpr shader_variable_type type() const noexcept override
	{
		return shader_variable_type::fvec1;
	}
	
	void update(float value) const noexcept override;
	void update(float value, std::size_t index) const override;
	void update(std::span<const float> values, std::size_t index = 0) const override;
	
private:
	GLint gl_uniform_location;
};

/**
 * 2-dimensional floating-point vector shader variable implementation using OpenGL.
 */
class gl_shader_fvec2: public shader_variable
{
public:
	gl_shader_fvec2(std::size_t size, GLint gl_uniform_location);
	
	[[nodiscard]] inline constexpr shader_variable_type type() const noexcept override
	{
		return shader_variable_type::fvec2;
	}
	
	void update(const math::fvec2& value) const noexcept override;
	void update(const math::fvec2& value, std::size_t index) const override;
	void update(std::span<const math::fvec2> values, std::size_t index = 0) const override;
	
private:
	GLint gl_uniform_location;
};

/**
 * 3-dimensional floating-point vector shader variable implementation using OpenGL.
 */
class gl_shader_fvec3: public shader_variable
{
public:
	gl_shader_fvec3(std::size_t size, GLint gl_uniform_location);
	
	[[nodiscard]] inline constexpr shader_variable_type type() const noexcept override
	{
		return shader_variable_type::fvec3;
	}
	
	void update(const math::fvec3& value) const noexcept override;
	void update(const math::fvec3& value, std::size_t index) const override;
	void update(std::span<const math::fvec3> values, std::size_t index = 0) const override;
	
private:
	GLint gl_uniform_location;
};

/**
 * 4-dimensional floating-point vector shader variable implementation using OpenGL.
 */
class gl_shader_fvec4: public shader_variable
{
public:
	gl_shader_fvec4(std::size_t size, GLint gl_uniform_location);
	
	[[nodiscard]] inline constexpr shader_variable_type type() const noexcept override
	{
		return shader_variable_type::fvec4;
	}
	
	void update(const math::fvec4& value) const noexcept override;
	void update(const math::fvec4& value, std::size_t index) const override;
	void update(std::span<const math::fvec4> values, std::size_t index = 0) const override;
	
private:
	GLint gl_uniform_location;
};

/**
 * 2x2 floating-point matrix shader variable implementation using OpenGL.
 */
class gl_shader_fmat2: public shader_variable
{
public:
	gl_shader_fmat2(std::size_t size, GLint gl_uniform_location);
	
	[[nodiscard]] inline constexpr shader_variable_type type() const noexcept override
	{
		return shader_variable_type::fmat2;
	}
	
	void update(const math::fmat2& value) const noexcept override;
	void update(const math::fmat2& value, std::size_t index) const override;
	void update(std::span<const math::fmat2> values, std::size_t index = 0) const override;
	
private:
	GLint gl_uniform_location;
};

/**
 * 3x3 floating-point matrix shader variable implementation using OpenGL.
 */
class gl_shader_fmat3: public shader_variable
{
public:
	gl_shader_fmat3(std::size_t size, GLint gl_uniform_location);
	
	[[nodiscard]] inline constexpr shader_variable_type type() const noexcept override
	{
		return shader_variable_type::fmat3;
	}
	
	void update(const math::fmat3& value) const noexcept override;
	void update(const math::fmat3& value, std::size_t index) const override;
	void update(std::span<const math::fmat3> values, std::size_t index = 0) const override;
	
private:
	GLint gl_uniform_location;
};

/**
 * 4x4 floating-point matrix shader variable implementation using OpenGL.
 */
class gl_shader_fmat4: public shader_variable
{
public:
	gl_shader_fmat4(std::size_t size, GLint gl_uniform_location);
	
	[[nodiscard]] inline constexpr shader_variable_type type() const noexcept override
	{
		return shader_variable_type::fmat4;
	}
	
	void update(const math::fmat4& value) const noexcept override;
	void update(const math::fmat4& value, std::size_t index) const override;
	void update(std::span<const math::fmat4> values, std::size_t index = 0) const override;
	
private:
	GLint gl_uniform_location;
};

/**
 * 1-dimensional texture shader variable implementation using OpenGL.
 */
class gl_shader_texture_1d: public shader_variable
{
public:
	gl_shader_texture_1d(std::size_t size, GLint gl_uniform_location, GLint gl_first_texture_index);
	
	[[nodiscard]] inline constexpr shader_variable_type type() const noexcept override
	{
		return shader_variable_type::texture_1d;
	}
	
	void update(const texture_1d& value) const noexcept override;
	void update(const texture_1d& value, std::size_t index) const override;
	void update(std::span<const texture_1d* const> values, std::size_t index = 0) const override;
	void update(std::span<const std::shared_ptr<texture_1d>> values, std::size_t index = 0) const override;
	
private:
	GLint gl_uniform_location;
	std::vector<GLint> gl_texture_unit_indices;
};

/**
 * 2-dimensional texture shader variable implementation using OpenGL.
 */
class gl_shader_texture_2d: public shader_variable
{
public:
	gl_shader_texture_2d(std::size_t size, GLint gl_uniform_location, GLint gl_first_texture_unit_index);
	
	[[nodiscard]] inline constexpr shader_variable_type type() const noexcept override
	{
		return shader_variable_type::texture_2d;
	}
	
	void update(const texture_2d& value) const noexcept override;
	void update(const texture_2d& value, std::size_t index) const override;
	void update(std::span<const texture_2d* const> values, std::size_t index = 0) const override;
	void update(std::span<const std::shared_ptr<texture_2d>> values, std::size_t index = 0) const override;
	
private:
	GLint gl_uniform_location;
	std::vector<GLint> gl_texture_unit_indices;
};

/**
 * 3-dimensional texture shader variable implementation using OpenGL.
 */
class gl_shader_texture_3d: public shader_variable
{
public:
	gl_shader_texture_3d(std::size_t size, GLint gl_uniform_location, GLint gl_first_texture_index);
	
	[[nodiscard]] inline constexpr shader_variable_type type() const noexcept override
	{
		return shader_variable_type::texture_3d;
	}
	
	void update(const texture_3d& value) const noexcept override;
	void update(const texture_3d& value, std::size_t index) const override;
	void update(std::span<const texture_3d* const> values, std::size_t index = 0) const override;
	void update(std::span<const std::shared_ptr<texture_3d>> values, std::size_t index = 0) const override;
	
private:
	GLint gl_uniform_location;
	std::vector<GLint> gl_texture_unit_indices;
};

/**
 * Cube texture shader variable implementation using OpenGL.
 */
class gl_shader_texture_cube: public shader_variable
{
public:
	gl_shader_texture_cube(std::size_t size, GLint gl_uniform_location, GLint gl_first_texture_index);
	
	[[nodiscard]] inline constexpr shader_variable_type type() const noexcept override
	{
		return shader_variable_type::texture_cube;
	}
	
	void update(const texture_cube& value) const noexcept override;
	void update(const texture_cube& value, std::size_t index) const override;
	void update(std::span<const texture_cube* const> values, std::size_t index = 0) const override;
	void update(std::span<const std::shared_ptr<texture_cube>> values, std::size_t index = 0) const override;
	
private:
	GLint gl_uniform_location;
	std::vector<GLint> gl_texture_unit_indices;
};

} // namespace gl

#endif // ANTKEEPER_GL_GL_SHADER_VARIABLES_HPP