ecs/test/src/main.cpp

#include "components.h"
#include "ecs-lua.h"
#include "ecs-serial.h"

#include <bits/stdint-intn.h>
#include <bits/stdint-uintn.h>
#include <cstddef>
#include <iostream>
#include <fstream>

#include <ostream>
#include <stdexcept>
#include <sys/types.h>
#include "ecs.h"
#include "ecs_components.h"

class Orb : public ecs::Entity {
	public:
		Orb(uuids::uuid uuid, float x, float y) : Entity(uuid) {
			auto position = add_component<Position>(x, y);
			auto velocity = add_component<Velocity>(0, 0);
		}
};

inline void handle_error(sol::optional<std::string> maybe_msg) {
	std::cerr << "Lua error, aborting!\n";
	if (maybe_msg) {
		const std::string& msg = maybe_msg.value();
		std::cerr << "Error: " << msg << '\n';
	}
}

int main(int argc, const char** argv) {
	bool save;
	if (argc == 2) {
		if (!std::string("save").compare(argv[1])) {
			save = true;
		} else if (!std::string("load").compare(argv[1])) {
			save = false;
		} else {
			std::cerr << "Usage: " << argv[0] << " [save/load]\n";
			return -1;
		}
	} else {
		std::cerr << "Usage: " << argv[0] << " [save/load]\n";
		return -1;
	}

	ecs::ComponentID::add<Position>("Position");
	ecs::ComponentID::add<Velocity>("Velocity");
	ecs::ComponentID::add<Meta>("Meta");

	sol::state lua(sol::c_call<decltype(&handle_error), &handle_error>);
	lua.open_libraries(sol::lib::base, sol::lib::package);

	ecs::lua::init(lua);

	generated::init(lua);
	generated::init();

	if (save) {
		ecs::Manager manager;

		// Testing interop with lua
		{

			lua.set_function("get_manager", [&manager] () -> ecs::Manager& {
				return manager;
			});

			lua.safe_script_file("test.lua");

			sol::protected_function init = lua["init"];
			std::cout << "Running init()\n";
			init();

			sol::protected_function run = lua["run"];
			std::cout << "Running run()\n";
			run();

			std::cout << "Update position\n";
			manager.view<Position, Velocity>().for_each([](ecs::Entity*, Position* pos, Velocity* vel) {
				pos->x += vel->x;
				pos->y += vel->y;
			});

			std::cout << "Show position!\n";
			manager.view<Position>().for_each([](ecs::Entity*, Position* pos) {
				std::cout << "X: " << pos->x << '\n';
				std::cout << "Y: " << pos->y << '\n';
			});

			std::cout << "Adding Orb!\n";
			manager.create_entity<Orb>(1.2f, 3.4f);
			for (auto [ent, pos, vel] : manager.view<Position, Velocity>()) {
				std::cout << "X: " << pos->x << " + " << vel->x << '\n';
				std::cout << "Y: " << pos->y << " + " << vel->y << '\n';
			}
		}

		// Test serialization
		{
			std::cout << "STORE\n";

			// Create entities and store them
			for (int i = 0; i < 10; ++i) {
				// We can create entities
				ecs::Entity* entity = manager.create_entity();
				// Then we can add components to them
				entity->add_component<Position>(0.0f, 0.0f);
				if (i % 2 == 0) {
					entity->add_component<Velocity>(0.1f, 0.2f);
				}
			}

			manager.view<Position, Velocity>().for_each([] (ecs::Entity*, Position* pos, Velocity* vel) {
				pos->x += vel->x;
				pos->y += vel->y;
			});

			std::ofstream file("entities", std::ios::out | std::ios::trunc);
			ecs::serial::serialize_ids(file);

			io::write<size_t>(file, manager.view<>().size());
			for (auto [entity] : manager.view<>()) {
				ecs::serial::serialize(file, entity);
			}
			file.close();

			manager.view<Position>().for_each([] (ecs::Entity* entity, Position* pos) {
				std::cout << "uuid: " << entity->uuid << '\n';
				std::cout << "x: " << pos->x << '\n';
				std::cout << "y: " << pos->y << '\n';
			});
		}
	} else {
		ecs::Manager manager;
		{
			std::cout << "LOAD\n";

			lua.safe_script_file("test2.lua");
			sol::protected_function init = lua["init"];
			std::cout << "Running init()\n";
			init();

			// Load entities from disk as a test
			std::ifstream file("entities", std::ios::in);

			ecs::serial::deserialize_ids(file);

			size_t entity_count = io::read<size_t>(file);
			size_t pos = file.tellg();
			for (size_t i = 0; i < entity_count; ++i) {
				ecs::serial::deserialize(file, manager);
			}

			// Load the first entity again (simulating an update)
			file.seekg(pos, std::ios::beg);
			ecs::serial::deserialize(file, manager);

			if (false) {
				auto ent = manager.get_entity(uuids::uuid::from_string("6d58fdb5-6d8c-4e6f-89d4-f7d7b184f463").value());
				if (ent->has_components<Position>()) {
					auto pos = ent->get_component<Position>();
					pos->x = 1.2f;
					pos->y = 3.4f;
				}
			}

			manager.view<Position>().for_each([] (ecs::Entity* entity, Position* pos) {
					std::cout << "uuid: " << entity->uuid << '\n';
					std::cout << "x: " << pos->x << '\n';
					std::cout << "y: " << pos->y << '\n';
					});

			lua.set_function("get_manager", [&manager] () -> ecs::Manager& {
					return manager;
					});

			sol::protected_function run = lua["run"];
			std::cout << "Running run()\n";
			run();
		}
	}

	for (auto [name, id] : ecs::ComponentID::get_map()) {
		std::cout << name << ' ' << id << '\n';
	}
}