#include <psemek/ecs/entity_container.hpp>

namespace psemek::ecs
{

	bool entity_container::alive(entity_handle const & entity) const
	{
		return entity_list_.get_entities()[entity.id].epoch == entity.epoch;
	}

	void entity_container::destroy(entity_handle const & entity)
	{
		// Swap with the last row in that table
		auto entities = entity_list_.get_entities();
		auto & data = entities[entity.id];
		auto table_entity_ids = data.table->get_entity_ids();
		data.table->swap_rows(data.row, table_entity_ids.size() - 1);
		data.table->pop_row();
		auto swap_id = table_entity_ids[data.row];
		auto & swap_data = entities[swap_id];
		swap_data.row = data.row;
		entity_list_.destroy(entity.id);
	}

	entity_accessor entity_container::get(entity_handle const & entity)
	{
		auto const & data = entity_list_.get_entities()[entity.id];
		return {data.table, data.row};
	}

}