#pragma once

#include "opengl/handles/shader_program_handle.hpp"
#include "rendering/batches/mesh_batch.hpp"
#include "assets/components/mesh_vertex_components.hpp"
#include "assets/components/material_components.hpp"
#include "opengl/handles/material_handle.hpp"
#include <span>

#include "geometry/aabb.hpp"
#include "rendering/modes/mesh_modes.hpp"
#include "rendering/shader_program_lookups/mesh_lookup.hpp"
#include "scene/lighting_setup.hpp"

namespace rendering
{
class mesh_batch_renderer
{
public:
	using batch_components_type = std::pair<
		mesh_vertex_components::flags,
		material_component::flags
	>;
	using batch_type = mesh_batch;
	using batch_index_type = ztu::u32;
	using batch_id_type = batch_index_type;
	using id_type = std::pair<batch_id_type, batch_type::id_type>;

	explicit mesh_batch_renderer(int render_mode_count);

	std::optional<id_type> add(
		const batch_components_type& batch_component,
		const zgl::mesh_handle& mesh,
		const aabb& bounding_box,
		const zgl::model_matrix_handle& transform,
		const zgl::material_handle& material,
		const shader_program_lookups::mesh_lookup& shader_program_lookup
	);

	std::optional<aabb> bounding_box(id_type);

	bool remove(id_type mesh_id);

	void render(
		modes::mesh render_mode,
		const glm::mat4& vp_matrix,
		const glm::mat4& view_matrix,
		const glm::vec3& view_pos,
		const lighting_setup& lights
	);

protected:
	[[nodiscard]] std::pair<std::size_t, bool> lookup_batch(const batch_components_type& batch_components) const;

private:
	int m_render_mode_count;

	std::vector<std::pair<batch_components_type, batch_index_type>> m_component_lookup{};
	std::vector<batch_id_type> m_id_lookup{};
	std::vector<std::pair<batch_type, batch_components_type>> m_batches{};
	std::vector<zgl::shader_program_handle> m_shader_programs{};

	batch_id_type m_next_batch_id{ 0 };
};
}