#pragma once

#include "shader_manager.hpp"
#include "assets/dynamic_data_stores/dynamic_shader_source_store.hpp"
#include "opengl/data/shader_program_data.hpp"
#include "opengl/shading/requirements/shader_program_requirements.hpp"
#include "opengl/metadata/shader_program_metadata.hpp"

namespace zgl
{

class shader_program_manager
{
	using shader_program_lookup_entry_type = std::pair<
		shader_program_metadata,
		shader_program_data
	>;

public:
	void process(
		const dynamic_shader_source_store& shader_sources
	);

	void get_handles(
		const dynamic_shader_source_store& shader_sources,
		std::span<const shading::shader_program_requirements> requirements,
		std::span<shader_program_metadata> metadata,
		std::span<shader_program_handle> shader_programs
	);

protected:
	std::optional<std::pair<shader_program_metadata, shader_program_handle>> find_shader_program(
		const shading::shader_program_requirements& requirements
	);

	bool link_shader_program(
		const shader_handle_set& shaders
	);

	shader_manager m_shader_manager;
	std::vector<shader_program_lookup_entry_type> m_shader_program_lookup;

private:

	std::vector<shading::shader_set_requirements> m_shader_requirements_buffer;
	std::vector<shader_set_metadata> m_shader_metadata_buffer;
	std::vector<shader_handle_set> shader_set_buffer;
};

}