script_component.h

#pragma once
 
#include <memory>
#include <string>
#include <string_view>
#include <vector>
 
#include "core/reflect.h"
#include "ecs/entity.h"
#include "ecs/scene.h"
#include "system/script/behavior.h"
#include "system/script/behavior_registry.h"
 
namespace Vkm::Engine {

struct UnknownBehavior {
    std::string type;
    std::string properties;  

    size_t index = 0;
};

struct ScriptComponent {
    std::vector<std::unique_ptr<Behavior>> behaviors;

    std::vector<UnknownBehavior> unknown;
};

EntityId findEntityWithBehaviorNamed(Scene& scene, std::string_view typeName);

void reportUnregisteredBehavior(const char* typeName);

template<typename T>
EntityId findEntityWithBehavior(Scene& scene) {
    return findEntityWithBehaviorNamed(scene, Reflect::Traits<T>::NAME);
}

template<typename T>
T& addBehavior(Scene& scene, EntityId entity) {
    const char* name = Reflect::Traits<T>::NAME;
    if (!BehaviorRegistry::get().contains(name)) reportUnregisteredBehavior(name);
 
    auto instance = std::make_unique<T>();
    T& behavior = *instance;
    ScriptComponent* script = scene.tryGet<ScriptComponent>(entity);
    if (!script) script = &scene.add(entity, ScriptComponent{});
    script->behaviors.push_back(std::move(instance));
    return behavior;
}
 
} // namespace Vkm::Engine