pythonscriptcomponent.h

/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
#pragma once
 
// Pybind includes
#include <pybind11/pybind11.h>
#include <pybind11/stl.h>
 
// Nap includes
#include <rtti/rtti.h>
#include <nap/signalslot.h>
#include <componentptr.h>
#include <nap/logger.h>
#include <instanceproperty.h>
#include <rtti/object.h>
#include <nap/resourceptr.h>
#include <entityptr.h>
#include <pythonscriptservice.h>
#include <pythonscript.h>
 
 
namespace nap
{
 
    // Forward declarations
    class PythonScriptComponent;
    class PythonScriptComponentInstance;
 
 
    class NAPAPI PythonScriptComponent : public Component
    {
        RTTI_ENABLE(Component)
        DECLARE_COMPONENT(PythonScriptComponent, PythonScriptComponentInstance)
 
        friend class PythonScriptComponentInstance;
 
    public:
        bool init(utility::ErrorState& errorState) override;
 
        ResourcePtr<PythonScript> mPythonScript = nullptr;  
        std::string mClassName;                             
        std::vector<std::string> mDependencies;             
 
        // Inherited from Component
        virtual void getDependentComponents(std::vector<rtti::TypeInfo>& components) const override;
 
    private:
        pybind11::module mModule;
        pybind11::object mPythonClass;
    };
 
 
    class NAPAPI PythonScriptComponentInstance : public ComponentInstance
    {
        RTTI_ENABLE(ComponentInstance)
    public:
        PythonScriptComponentInstance(EntityInstance& entity, Component& resource);
        ~PythonScriptComponentInstance();
 
        // Inherited from ComponentInstance
        virtual void update(double deltaTime) override;
        bool init(utility::ErrorState& errorState) override;
 
        template <typename ReturnType, typename ...Args>
        bool get(const std::string& identifier, utility::ErrorState& errorState, ReturnType& returnValue, Args&&... args);
 
        template <typename ...Args>
        bool call(const std::string& identifier, utility::ErrorState& errorState, Args&&... args);
 
    private:
        PythonScriptComponent* mResource = nullptr;
        pybind11::object mInstance;
        bool mInitialized = false;
    };
 
 
    // Template Definitions
 
    template <typename ReturnType, typename ...Args>
    bool PythonScriptComponentInstance::get(const std::string& identifier, utility::ErrorState& errorState, ReturnType& returnValue, Args&&... args)
    {
        try
        {
            returnValue = mInstance.attr(identifier.c_str())(args...).template cast<ReturnType>();
        }
        catch (const pybind11::error_already_set& err)
        {
            errorState.fail("Runtime python error while executing %s: %s", mResource->mPythonScript->mPath.c_str(), err.what());
            return false;
        }
        return true;
    }
 
 
    template <typename ...Args>
    bool PythonScriptComponentInstance::call(const std::string& identifier, utility::ErrorState& errorState, Args&&... args)
    {
        try
        {
            mInstance.attr(identifier.c_str())(std::forward<Args>(args)...);
        }
        catch (const pybind11::error_already_set& err)
        {
            errorState.fail("Runtime python error while executing %s: %s", mResource->mPythonScript->mPath.c_str(), err.what());
            return false;
        }
        return true;
    }
}