Add C++ variant of x0 framework with Qt and nlohmann::json

.gitignore

@@ -20,3 +20,5 @@ debian/x0-db-install
 debian/x0-db-install-tpl
 debian/x0-msg-server
 debian/.debhelper
+_codeql_detected_source_root
+cpp/build/

cpp/CMakeLists.txt

@@ -0,0 +1,90 @@
+#-------1---------2---------3---------4---------5---------6---------7--------#
+#- Copyright WEB/codeX, clickIT 2011 - 2025                                 -#
+#-------1---------2---------3---------4---------5---------6---------7--------#
+#-                                                                          -#
+#-------1---------2---------3---------4---------5---------6---------7--------#
+#- x0 C++ Framework - CMake Build Configuration                             -#
+#-------1---------2---------3---------4---------5---------6---------7--------#
+
+cmake_minimum_required(VERSION 3.16)
+project(x0-cpp VERSION 1.0.0 LANGUAGES CXX)
+
+set(CMAKE_CXX_STANDARD 20)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+set(CMAKE_AUTOMOC ON)
+set(CMAKE_AUTORCC ON)
+set(CMAKE_AUTOUIC ON)
+
+# Find required packages
+find_package(Qt6 COMPONENTS Core Widgets QUIET)
+if(NOT Qt6_FOUND)
+    find_package(Qt5 5.15 COMPONENTS Core Widgets REQUIRED)
+    set(QT_LIBS Qt5::Core Qt5::Widgets)
+else()
+    set(QT_LIBS Qt6::Core Qt6::Widgets)
+endif()
+
+# nlohmann/json - Header-only library
+# Can be installed via: apt-get install nlohmann-json3-dev
+# Or fetched automatically
+include(FetchContent)
+FetchContent_Declare(
+    json
+    GIT_REPOSITORY https://github.com/nlohmann/json.git
+    GIT_TAG v3.11.3
+)
+FetchContent_MakeAvailable(json)
+
+# Include directories
+include_directories(${CMAKE_CURRENT_SOURCE_DIR}/include)
+
+# Library source files (without main.cpp)
+set(X0_LIB_SOURCES
+    src/x0BaseElement.cpp
+    src/x0BaseObject.cpp
+    src/x0Factory.cpp
+    src/x0Screen.cpp
+    src/x0Reactor.cpp
+    src/x0ObjDiv.cpp
+    src/x0ObjButton.cpp
+)
+
+# Header files
+set(X0_HEADERS
+    include/x0BaseElement.h
+    include/x0BaseObject.h
+    include/x0Factory.h
+    include/x0Screen.h
+    include/x0Reactor.h
+    include/x0ObjDiv.h
+    include/x0ObjButton.h
+)
+
+# Create static library
+add_library(x0-lib STATIC ${X0_LIB_SOURCES} ${X0_HEADERS})
+target_link_libraries(x0-lib PUBLIC
+    ${QT_LIBS}
+    nlohmann_json::nlohmann_json
+)
+
+# Create main executable
+add_executable(x0-app src/main.cpp)
+target_link_libraries(x0-app PRIVATE x0-lib)
+
+# Create test executable for validating examples
+add_executable(x0-test-examples test/test_examples.cpp)
+target_link_libraries(x0-test-examples PRIVATE
+    x0-lib
+    nlohmann_json::nlohmann_json
+)
+
+# Enable testing
+enable_testing()
+
+# Define examples directory path
+set(EXAMPLES_DIR "${CMAKE_CURRENT_SOURCE_DIR}/../example")
+add_test(NAME test_examples COMMAND x0-test-examples "${EXAMPLES_DIR}")
+
+# Install targets
+install(TARGETS x0-app DESTINATION bin)
+install(FILES ${X0_HEADERS} DESTINATION include/x0)

cpp/README.md

@@ -0,0 +1,174 @@
+# x0 C++ Framework
+
+C++ variant of the x0 JavaScript framework using **Qt** for graphical rendering and **nlohmann::json** for configuration management.
+
+## Overview
+
+This directory contains a C++ implementation of the x0 framework, providing equivalent functionality to the JavaScript version in `/www/`. The C++ variant is designed for desktop applications requiring native performance and Qt-based graphical output.
+
+## Architecture
+
+The C++ framework mirrors the JavaScript architecture:
+
+| JavaScript (`/www/`)       | C++ (`/cpp/`)          | Description                                    |
+|---------------------------|------------------------|------------------------------------------------|
+| `sysBaseDOMElement.js`    | `x0BaseElement.h/cpp`  | Base element wrapping Qt widgets               |
+| `sysBaseObject.js`        | `x0BaseObject.h/cpp`   | Hierarchical object with children              |
+| `sysFactory.js`           | `x0Factory.h/cpp`      | Object factory and screen management           |
+| `sysScreen.js`            | `x0Screen.h/cpp`       | Screen/view management                         |
+| `sysReactor.js`           | `x0Reactor.h/cpp`      | Event system                                   |
+| `sysObjDiv.js`            | `x0ObjDiv.h/cpp`       | Container widget (QFrame)                      |
+| `sysObjButton.js`         | `x0ObjButton.h/cpp`    | Button widget (QPushButton)                    |
+
+## Dependencies
+
+- **Qt 5.15+** or **Qt 6.x** (Core, Widgets modules)
+- **nlohmann/json 3.x** (automatically fetched via CMake)
+- **CMake 3.16+**
+
+## Building
+
+### Prerequisites
+
+```bash
+# Ubuntu/Debian
+sudo apt-get install cmake qt6-base-dev
+
+# Or for Qt5
+sudo apt-get install cmake qtbase5-dev
+```
+
+### Build Steps
+
+```bash
+cd cpp
+mkdir build && cd build
+cmake ..
+make -j$(nproc)
+```
+
+### Running
+
+```bash
+./x0-app
+```
+
+## Usage Example
+
+```cpp
+#include "x0Factory.h"
+#include "x0Screen.h"
+#include "x0ObjDiv.h"
+#include "x0ObjButton.h"
+
+using namespace x0;
+
+int main() {
+    // Load configuration
+    json skeleton = loadFromFile("skeleton.json");
+    json dataObject = loadFromFile("objects.json");
+
+    // Initialize factory
+    x0Factory& factory = x0Factory::instance();
+    factory.setDataSkeleton(skeleton);
+    factory.setDataObject(dataObject);
+    factory.init();
+
+    // Access screens and objects
+    x0Screen* screen = factory.getScreenById("MainScreen");
+    x0BaseObject* button = factory.getObjectById("MyButton");
+
+    return 0;
+}
+```
+
+## JSON Configuration
+
+The C++ framework uses the same JSON configuration format as the JavaScript version:
+
+### Skeleton Configuration
+```json
+{
+    "MainScreen": [
+        {"MainDiv": {"RefID": "MainScreen"}},
+        {"WelcomeText": {"RefID": "MainDiv"}},
+        {"ActionButton": {"RefID": "MainDiv"}}
+    ]
+}
+```
+
+### Object Configuration
+```json
+{
+    "ActionButton": {
+        "Type": "Button",
+        "Attributes": {
+            "Style": "btn btn-primary",
+            "TextID": "BTN.SUBMIT",
+            "OnClick": "/api/submit",
+            "FireEvents": ["DataRefresh"]
+        }
+    }
+}
+```
+
+## Class Hierarchy
+
+```
+QObject
+└── x0BaseElement (Qt widget wrapper)
+    └── x0BaseObject (hierarchical object)
+        ├── x0ObjDiv (container)
+        └── x0ObjButton (button)
+
+x0Factory (singleton, object management)
+x0Screen (screen/view container)
+x0Reactor (event dispatching)
+```
+
+## Features
+
+- **Hierarchical Object Model**: Parent-child relationships with recursive rendering
+- **JSON Configuration**: Load UI definitions from JSON files
+- **Qt Integration**: Native desktop widgets with Qt
+- **Event System**: Register and dispatch events across objects
+- **Screen Management**: Multiple screens with switching support
+- **Object Factory**: Dynamic object creation by type
+
+## Extending
+
+To add new widget types:
+
+1. Create header in `include/`:
+```cpp
+// x0ObjMyWidget.h
+class x0ObjMyWidget : public x0BaseObject {
+    Q_OBJECT
+public:
+    void createWidget(const QString& objectId) override;
+    void init() override;
+};
+```
+
+2. Create implementation in `src/`:
+```cpp
+// x0ObjMyWidget.cpp
+void x0ObjMyWidget::createWidget(const QString& objectId) {
+    m_widget = std::make_unique<QMyWidget>();
+    m_widget->setObjectName(objectId);
+}
+```
+
+3. Register in factory:
+```cpp
+x0Factory::instance().registerObjectType("MyWidget", 
+    []() { return std::make_shared<x0ObjMyWidget>(); });
+```
+
+## License
+
+AGPL-3.0 - See [../LICENSE](../LICENSE)
+
+## Contributing
+
+See [../CONTRIBUTING.md](../CONTRIBUTING.md)

cpp/include/x0BaseElement.h

@@ -0,0 +1,109 @@
+//-------1---------2---------3---------4---------5---------6---------7--------//
+//- Copyright WEB/codeX, clickIT 2011 - 2025                                 -//
+//-------1---------2---------3---------4---------5---------6---------7--------//
+//-                                                                          -//
+//-------1---------2---------3---------4---------5---------6---------7--------//
+//- x0 C++ Framework - Base Element (Qt Widget Wrapper)                      -//
+//-------1---------2---------3---------4---------5---------6---------7--------//
+//- Equivalent to JavaScript: sysBaseDOMElement.js                           -//
+//-------1---------2---------3---------4---------5---------6---------7--------//
+
+#ifndef X0_BASE_ELEMENT_H
+#define X0_BASE_ELEMENT_H
+
+#include <QWidget>
+#include <QString>
+#include <QMap>
+#include <memory>
+#include <nlohmann/json.hpp>
+
+namespace x0 {
+
+using json = nlohmann::json;
+
+/**
+ * @brief Base element class wrapping Qt widgets
+ * 
+ * This class provides the foundation for all UI elements in the x0 C++ framework.
+ * It manages the underlying Qt widget and provides methods for styling,
+ * visibility control, and event handling - equivalent to sysBaseDOMElement.js.
+ */
+class x0BaseElement : public QObject {
+    Q_OBJECT
+
+public:
+    explicit x0BaseElement(QObject* parent = nullptr);
+    virtual ~x0BaseElement();
+
+    // Widget management
+    virtual void createWidget(const QString& objectId);
+    virtual QWidget* getWidget() const;
+    void setParentWidget(QWidget* parent);
+
+    // Style management
+    void setStyleClass(const QString& styleClass);
+    void addStyleClass(const QString& styleClass);
+    void removeStyleClass(const QString& styleClass);
+    bool hasStyleClass(const QString& styleClass) const;
+    QString getStyleClasses() const;
+
+    // Value management
+    void setValue(const QString& value);
+    QString getValue() const;
+
+    // Visibility
+    void setVisibleState(const QString& state);
+    QString getVisibleState() const;
+    void switchVisibleState();
+
+    // Enable/Disable
+    void enable();
+    void disable();
+    bool isEnabled() const;
+
+    // Attributes
+    void setAttribute(const QString& attribute, const QString& value);
+    QString getAttribute(const QString& attribute) const;
+    void setAttributes(const QMap<QString, QString>& attributes);
+
+    // Style properties
+    void setStyleTop(int top);
+    void setStyleLeft(int left);
+    void setStyleWidth(int width);
+    void setStyleHeight(int height);
+    void setStyleZIndex(int zIndex);
+    void applyStyleAttributes();
+
+    // Object identification
+    QString getObjectId() const { return m_objectId; }
+    void setObjectId(const QString& id) { m_objectId = id; }
+    QString getParentId() const { return m_parentId; }
+    void setParentId(const QString& id) { m_parentId = id; }
+
+protected:
+    std::unique_ptr<QWidget> m_widget;
+    QString m_objectId;
+    QString m_parentId;
+    QString m_value;
+    QString m_styleClass;
+    QString m_visibleState;
+    QMap<QString, QString> m_attributes;
+
+    // Style positioning
+    int m_styleTop = -1;
+    int m_styleLeft = -1;
+    int m_styleWidth = -1;
+    int m_styleHeight = -1;
+    int m_styleZIndex = -1;
+
+    QStringList m_styleClasses;
+
+signals:
+    void visibilityChanged(bool visible);
+    void styleChanged();
+    void valueChanged(const QString& value);
+};
+
+} // namespace x0
+
+#endif // X0_BASE_ELEMENT_H