ComponentDefinition.h

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/*
Olympe Engine V2 - 2025
Nicolas Chereau
nchereau@gmail.com
 
This file is part of Olympe Engine V2.
 
ComponentDefinition purpose: Provides dynamic component parameter storage and JSON parsing
for entity components. Supports type-safe parameter access and conversions.
*/
 
#pragma once
 
#include <string>
#include <map>
#include <memory>
#include <SDL3/SDL.h>
#include "vector.h"
#include "ECS_Entity.h"
 
// Forward declaration
namespace nlohmann {
    class json;
}
 
struct ComponentParameter
{
    enum class Type : uint8_t
    {
        Unknown = 0,
        Bool,
        Int,
        Float,
        String,
        Vector2,
        Vector3,
        Color,
        Array,
        EntityRef
    };
 
    Type type = Type::Unknown;
 
    // Value storage
    bool boolValue = false;
    int intValue = 0;
    float floatValue = 0.0f;
    std::string stringValue;
    Vector vectorValue;
    SDL_Color colorValue = { 255, 255, 255, 255 };
    EntityID entityRefValue = INVALID_ENTITY_ID;
    
    // Array storage (uses nlohmann::json for C++14 compatibility)
    // Initialized to null by default, set to json::array() when Type::Array is used
    std::shared_ptr<nlohmann::json> arrayValue;
 
    // Factory methods
    static ComponentParameter FromBool(bool value);
    static ComponentParameter FromInt(int value);
    static ComponentParameter FromFloat(float value);
    static ComponentParameter FromString(const std::string& value);
    static ComponentParameter FromVector2(float x, float y);
    static ComponentParameter FromVector3(float x, float y, float z);
    static ComponentParameter FromColor(uint8_t r, uint8_t g, uint8_t b, uint8_t a = 255);
    static ComponentParameter FromEntityRef(EntityID entityId);
    static ComponentParameter FromArray(const nlohmann::json& arrayData);
 
    // Type conversion helpers with fallback logic
    bool AsBool() const;
    int AsInt() const;
    float AsFloat() const;
    std::string AsString() const;
    Vector AsVector() const;
    SDL_Color AsColor() const;
    EntityID AsEntityRef() const;
    const nlohmann::json& AsArray() const;
};
 
struct ComponentDefinition
{
    std::string componentType;
    std::map<std::string, ComponentParameter> parameters;
 
    // JSON parsing with type detection heuristics
    static ComponentDefinition FromJSON(const nlohmann::json& jsonObj);
 
    // Parameter access
    bool HasParameter(const std::string& name) const;
    const ComponentParameter* GetParameter(const std::string& name) const;
};
 
// Helper function to convert ParameterType enum to string
std::string ParameterTypeToString(ComponentParameter::Type type);
 
// Schema-aware parameter parsing
ComponentParameter ParseParameterWithSchema(
    const std::string& componentType,
    const std::string& paramName,
    const nlohmann::json& jsonValue
);