feat(qt6): visual workflow canvas with infinite pan/zoom, Bezier connections, 152-node palette

Replace list-based WorkflowEditor with spatial infinite canvas: - NodeRegistry C++ class loads 152 node types from node-registry.json - 5000x5000 Flickable canvas with grid, Scale transform zoom (0.25x-2x) - Draggable nodes with group-colored headers, input/output ports - Bezier connection drawing via Canvas 2D (n8n adjacency map format) - Interactive port-to-port connection creation with drag preview - Searchable/filterable node palette with group chips - Properties panel with schema-driven parameter editing - Full n8n-style JSON: nodes, connections, variables, meta, tags - DBAL integration preserved with mock workflow fallback Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
2026-04-24 13:54:57 +00:00 · 2026-03-19 03:03:34 +00:00
parent e0893c2fe3
commit e6a2a50ae1
8 changed files with 1676 additions and 535 deletions
--- a/frontends/qt6/CMakeLists.txt
+++ b/frontends/qt6/CMakeLists.txt
@@ -1,3 +1,30 @@
+# AUTO-GENERATED by generate_cmake.py — do not edit manually
+# Generated from cmake_config.json | 91 QML files, 6 C++ sources, 22 SVGs, 1 audio assets
+#
+# Discovered packages:
+#   analytics            v1.0.0 - Analytics Studio
+#   blog                 v1.0.0 - Blog
+#   breakout             v1.0.0 - Breakout
+#   connection_hub       v1.0.0 - Connection Hub
+#   escape_room          v1.0.0 - Escape Room
+#   forum                v1.0.0 - Community Forum
+#   frontpage            v1.0.0 - Frontpage Experience
+#   gallery              v1.0.0 - Gallery
+#   god_panel            v1.0.0 - God Panel
+#   guestbook            v1.0.0 - Guestbook
+#   login                v1.0.0 - Login Shell
+#   marketplace          v1.0.0 - Marketplace
+#   microthread          v1.0.0 - MicroThread
+#   music_player         v1.0.0 - Music Player
+#   package_manager      v1.0.0 - Package Manager
+#   profile_page         v1.0.0 - Profile Page
+#   retro_games          v1.0.0 - Retro Arcade
+#   snake_game           v1.0.0 - Snake Game
+#   storybook            v1.0.0 - Storybook Showcase
+#   supergod_panel       v1.0.0 - SuperGod Panel
+#   user_settings        v1.0.0 - User Settings
+#   watchtower           v1.0.0 - Watchtower
+
 cmake_minimum_required(VERSION 3.27)
 project(dbal_qml VERSION 0.1 LANGUAGES CXX)

@@ -18,54 +45,118 @@ qt_policy(SET QTP0001 NEW)

 qt_add_executable(dbal-qml
    main.cpp
-    src/PackageRegistry.cpp
-    src/ModPlayer.cpp
    src/DBALClient.cpp
+    src/ModPlayer.cpp
+    src/NodeRegistry.cpp
    src/PackageLoader.cpp
+    src/PackageRegistry.cpp
 )

-# Pass source dir so the binary can find shared QML components at runtime
 target_compile_definitions(dbal-qml PRIVATE SRCDIR="${CMAKE_CURRENT_SOURCE_DIR}")

 qt_add_qml_module(dbal-qml
    URI DBALObservatory
    VERSION 1.0
    QML_FILES
-        App.qml
-        FrontPage.qml
-        LoginView.qml
-        DashboardView.qml
        AdminView.qml
-        PackageViewLoader.qml
-        ProfileView.qml
+        App.qml
        CommentsView.qml
-        GodPanel.qml
-        SchemaEditor.qml
-        WorkflowEditor.qml
-        LuaEditor.qml
-        DatabaseManager.qml
-        PageRoutesManager.qml
        ComponentHierarchyEditor.qml
        CssClassManager.qml
+        DashboardView.qml
+        DatabaseManager.qml
        DropdownConfigManager.qml
-        UserManagement.qml
-        ThemeEditor.qml
-        SMTPConfigEditor.qml
-        SuperGodPanel.qml
+        FrontPage.qml
+        GodPanel.qml
+        LoginView.qml
+        LuaEditor.qml
        MaterialLanding.qml
-        ModPlayerPanel.qml
-        PackageManager.qml
-        Storybook.qml
        MediaServicePanel.qml
+        ModPlayerPanel.qml
        NotificationsPanel.qml
+        PackageManager.qml
+        PackageViewLoader.qml
+        PageRoutesManager.qml
+        ProfileView.qml
+        SMTPConfigEditor.qml
+        SchemaEditor.qml
        SettingsView.qml
+        Storybook.qml
+        SuperGodPanel.qml
+        ThemeEditor.qml
+        UserManagement.qml
+        WorkflowEditor.qml
+        qmllib/Material/MaterialAccordion.qml
+        qmllib/Material/MaterialAlert.qml
+        qmllib/Material/MaterialAppBar.qml
+        qmllib/Material/MaterialAvatar.qml
+        qmllib/Material/MaterialBadge.qml
+        qmllib/Material/MaterialBox.qml
+        qmllib/Material/MaterialButton.qml
+        qmllib/Material/MaterialCard.qml
+        qmllib/Material/MaterialCheckbox.qml
+        qmllib/Material/MaterialChip.qml
+        qmllib/Material/MaterialCircularProgress.qml
+        qmllib/Material/MaterialCollapse.qml
+        qmllib/Material/MaterialContainer.qml
+        qmllib/Material/MaterialDialog.qml
+        qmllib/Material/MaterialDivider.qml
+        qmllib/Material/MaterialDividerProps.qml
+        qmllib/Material/MaterialGrid.qml
+        qmllib/Material/MaterialIconButton.qml
+        qmllib/Material/MaterialLinearProgress.qml
+        qmllib/Material/MaterialLink.qml
+        qmllib/Material/MaterialMenu.qml
+        qmllib/Material/MaterialMenuItem.qml
+        qmllib/Material/MaterialMenuProps.qml
+        qmllib/Material/MaterialPalette.qml
+        qmllib/Material/MaterialPaper.qml
+        qmllib/Material/MaterialPopover.qml
+        qmllib/Material/MaterialPopoverProps.qml
+        qmllib/Material/MaterialSkeleton.qml
+        qmllib/Material/MaterialSnackbar.qml
+        qmllib/Material/MaterialSurface.qml
+        qmllib/Material/MaterialSwitch.qml
+        qmllib/Material/MaterialTextField.qml
+        qmllib/Material/MaterialToolbar.qml
+        qmllib/Material/MaterialTypography.qml
+        qmllib/MetaBuilder/ContactForm.qml
+        qmllib/MetaBuilder/FeatureCard.qml
+        qmllib/MetaBuilder/HeroSection.qml
+        qmllib/MetaBuilder/NavBar.qml
+        qmllib/MetaBuilder/StatusCard.qml
+        qmllib/MetaBuilder/WorkflowNode.qml
        qmllib/dbal/DBALProvider.qml
+        packages/analytics/PackageView.qml
+        packages/blog/PackageView.qml
+        packages/breakout/PackageView.qml
+        packages/connection-hub/PackageView.qml
+        packages/escape-room/PackageView.qml
+        packages/forum/PackageView.qml
+        packages/frontpage/PackageView.qml
+        packages/gallery/PackageView.qml
+        packages/god-panel/PackageView.qml
+        packages/guestbook/PackageView.qml
+        packages/login/PackageView.qml
+        packages/marketplace/PackageView.qml
+        packages/microthread/PackageView.qml
+        packages/music-player/PackageView.qml
+        packages/package-manager/PackageView.qml
+        packages/profile-page/PackageView.qml
+        packages/retro-games/PackageView.qml
+        packages/snake-game/PackageView.qml
+        packages/storybook/PackageView.qml
+        packages/supergod-panel/PackageView.qml
+        packages/user-settings/PackageView.qml
+        packages/watchtower/PackageView.qml
    RESOURCES
        assets/audio/retro-gaming.mod
+        qmllib/Material/qmldir
+        qmllib/MetaBuilder/qmldir
        qmllib/dbal/qmldir
 )

-# Add SVG assets
+# SVG assets
 file(GLOB SVG_ASSETS RELATIVE ${CMAKE_CURRENT_SOURCE_DIR} assets/svg/*.svg)
 qt_add_resources(dbal-qml "svg_assets"
    PREFIX "/"
@@ -76,9 +167,7 @@ target_link_libraries(dbal-qml PRIVATE
    Qt6::Core Qt6::Gui Qt6::Quick Qt6::Qml Qt6::Network
 )

-# Conan Qt recipe adds module-specific include dirs to CMAKE_INCLUDE_PATH
-# but MSVC needs them as actual compiler include paths.
-# Add the Qt root include + all module subdirs from CMAKE_INCLUDE_PATH.
+# Conan Qt recipe: propagate CMAKE_INCLUDE_PATH entries for MSVC
 foreach(_inc ${CMAKE_INCLUDE_PATH})
    target_include_directories(dbal-qml PRIVATE "${_inc}")
 endforeach()
--- a/frontends/qt6/PLAN.md
+++ b/frontends/qt6/PLAN.md
@@ -0,0 +1,107 @@
+# Phase 9: Visual Workflow Canvas + Frontend Parity
+
+**Status**: In Progress
+**Started**: 2026-03-19
+
+---
+
+## Part A: QML Workflow Canvas (PRIMARY)
+
+Replace the list-based WorkflowEditor with a spatial infinite canvas.
+
+### Steps
+
+- [x] **Step 1: NodeRegistry C++ class** ✓
+  - New `src/NodeRegistry.h` + `src/NodeRegistry.cpp`
+  - Reads `workflow/plugins/registry/node-registry.json`
+  - Exposes `nodeTypes()`, `groups()`, `nodeType(name)`, `nodesByGroup()`, `searchNodes()` to QML
+  - Registered as context property `NodeRegistry` in `main.cpp`
+  - Auto-discovered by `generate_cmake.py` (6 C++ sources total)
+
+- [x] **Step 2: Canvas Infrastructure** ✓
+  - `Flickable` 5000x5000 with grid background
+  - `Scale` transform for zoom (0.25x–2x)
+  - Mousewheel zoom, zoom overlay with +/- buttons
+  - `Canvas` 2D connection layer + `Repeater` node layer
+
+- [x] **Step 3: WorkflowNode Component** ✓
+  - `qmllib/MetaBuilder/WorkflowNode.qml` with DragHandler
+  - Colored header by group (prefix-based color mapping)
+  - Input ports (left, blue), output ports (right, green)
+  - Click-to-select with visual highlight
+  - Inline node delegates in WorkflowEditor for tight integration
+
+- [x] **Step 4: Bezier Connection Drawing** ✓
+  - QML `Canvas` with `context.bezierCurveTo()`
+  - Parses n8n-style `connections` adjacency map
+  - Control points offset 40% of horizontal distance
+  - Arrow heads at destination ports
+  - Dashed line for connection being drawn
+  - `requestPaint()` on node drag and connection changes
+
+- [x] **Step 5: Node Palette (Left Sidebar)** ✓
+  - ListView from `NodeRegistry.nodeTypes` filtered by search + group
+  - Group filter chips (All, core, logic, transform, integration, etc.)
+  - Double-click to add at canvas center
+  - `Drag.active` + `DropArea` for drag-to-canvas
+
+- [x] **Step 6: Properties Panel (Right Sidebar)** ✓
+  - Animated slide-in panel (300px)
+  - Name (editable), Type (badge with group color)
+  - Parameters from `NodeRegistry.nodeType()` schema
+  - Dynamic text fields and dropdowns for property options
+  - Input/output port display with chips
+  - Workflow variables display
+  - Position readout, Delete button
+
+- [x] **Step 7: Workflow I/O** ✓
+  - Full n8n-style JSON: name, active, settings, tags, meta, variables, nodes, connections
+  - DBAL load/save via `DBALProvider.list/create/update/remove`
+  - Mock workflows with realistic graph layouts as fallback
+  - Add/remove nodes + connections with proper cleanup
+
+### Files
+
+| File | Action |
+|------|--------|
+| `WorkflowEditor.qml` | Full rewrite — spatial canvas |
+| `qmllib/MetaBuilder/WorkflowNode.qml` | New — draggable node component |
+| `src/NodeRegistry.h` | New — C++ node type loader |
+| `src/NodeRegistry.cpp` | New — implementation |
+| `main.cpp` | Register NodeRegistry context property |
+| `CMakeLists.txt` | Add NodeRegistry to sources |
+
+### Verification
+
+1. Build compiles clean
+2. God Panel → Workflows tab shows canvas
+3. Pan (scroll) + zoom (Ctrl+scroll) works
+4. Load `seed_game.json` (58 nodes) renders correctly
+5. Drag from palette → node on canvas
+6. Port-to-port connection drawing
+7. Properties panel for selected node
+8. Save roundtrip to DBAL
+
+---
+
+## Part B: Next.js Frontend Alignment (LATER)
+
+- [ ] Level-based layout (5 levels matching `old/`)
+- [ ] Sidebar navigation matching Qt6
+- [ ] God Panel tabs
+- [ ] Wire in workflowui editor
+
+## Part C: CLI Feature Parity (LATER)
+
+- [ ] `workflow list/get/run/create` commands
+- [ ] `package list/install/uninstall` commands
+
+---
+
+## Reusable Code
+
+- `DBALProvider.qml` — DBAL REST client (keep as-is)
+- `PackageLoader` C++ pattern — template for NodeRegistry
+- `node-registry.json` — 152 node types
+- `components/workflow-editor/ConnectionLine.tsx` — Bezier math reference
+- `gameengine/packages/seed/workflows/*.json` — test data
--- a/frontends/qt6/WorkflowEditor.qml
+++ b/frontends/qt6/WorkflowEditor.qml
--- a/frontends/qt6/main.cpp
+++ b/frontends/qt6/main.cpp
@@ -8,6 +8,7 @@
 #include "src/ModPlayer.h"
 #include "src/DBALClient.h"
 #include "src/PackageLoader.h"
+#include "src/NodeRegistry.h"

 int main(int argc, char *argv[]) {
    QGuiApplication app(argc, argv);
@@ -16,15 +17,20 @@ int main(int argc, char *argv[]) {
    // Add shared QML component library path
    // Resolves: import QmlComponents 1.0
    const auto appDir = QCoreApplication::applicationDirPath();
-    const QStringList qmlPaths = {
-        appDir + "/../../qml",
-        appDir + "/../../../qml",
-        appDir + "/../../../../qml",
-        QDir::cleanPath(QStringLiteral(SRCDIR) + "/../../qml")
+    // Qt6 resolves "import QmlComponents" by looking for a QmlComponents/ dir
+    // inside each import path. We symlink or reference the parent of qml/.
+    const QStringList qmlParentPaths = {
+        appDir + "/../../",
+        appDir + "/../../../",
+        appDir + "/../../../../",
+        QDir::cleanPath(QStringLiteral(SRCDIR) + "/../..")
    };
-    for (const auto &path : qmlPaths) {
-        if (QDir(path).exists()) {
-            engine.addImportPath(QDir(path).absolutePath());
+    for (const auto &path : qmlParentPaths) {
+        const QString candidate = QDir(path).absolutePath();
+        // Check if QmlComponents symlink or qml/ dir with qmldir exists
+        if (QDir(candidate + "/QmlComponents").exists()
+            || QDir(candidate + "/qml").exists()) {
+            engine.addImportPath(candidate);
            break;
        }
    }
@@ -33,16 +39,24 @@ int main(int argc, char *argv[]) {
    ModPlayer modPlayer;
    DBALClient dbalClient;
    PackageLoader packageLoader;
+    NodeRegistry nodeRegistry;
    registry.loadPackage("frontpage");
    packageLoader.setPackagesDir(QDir(QStringLiteral(SRCDIR) + QStringLiteral("/packages")).absolutePath());
    packageLoader.scan();
    packageLoader.setWatching(true);
+
+    // Load workflow node type registry
+    const QString registryPath = QDir::cleanPath(
+        QStringLiteral(SRCDIR) + QStringLiteral("/../../workflow/plugins/registry/node-registry.json"));
+    nodeRegistry.loadRegistry(registryPath);
+
    engine.rootContext()->setContextProperty(QStringLiteral("PackageRegistry"), &registry);
    engine.rootContext()->setContextProperty(QStringLiteral("ModPlayer"), &modPlayer);
    engine.rootContext()->setContextProperty(QStringLiteral("DBALClient"), &dbalClient);
    engine.rootContext()->setContextProperty(QStringLiteral("PackageLoader"), &packageLoader);
+    engine.rootContext()->setContextProperty(QStringLiteral("NodeRegistry"), &nodeRegistry);

-    const QUrl url(QStringLiteral("qrc:/DBALObservatory/App.qml"));
+    const QUrl url(QStringLiteral("qrc:/qt/qml/DBALObservatory/App.qml"));
    QObject::connect(&engine, &QQmlApplicationEngine::objectCreated,
                     &app, [url](QObject *obj, const QUrl &objUrl) {
                         if (!obj && objUrl == url)
--- a/frontends/qt6/qmllib/MetaBuilder/WorkflowNode.qml
+++ b/frontends/qt6/qmllib/MetaBuilder/WorkflowNode.qml
@@ -0,0 +1,214 @@
+import QtQuick
+import QtQuick.Controls
+import QtQuick.Layouts
+import QmlComponents 1.0
+
+Rectangle {
+    id: nodeRoot
+
+    property string nodeId: ""
+    property string nodeName: "Node"
+    property string nodeType: "action"
+    property string displayName: ""
+    property var nodeInputs: []
+    property var nodeOutputs: []
+    property var parameters: ({})
+    property real nodeX: 0
+    property real nodeY: 0
+    property bool selected: false
+    property real zoom: 1.0
+
+    // Port geometry constants
+    readonly property int portRadius: 6
+    readonly property int portSpacing: 24
+    readonly property int headerHeight: 32
+    readonly property int minWidth: 180
+    readonly property int minHeight: headerHeight + Math.max(nodeInputs.length, nodeOutputs.length) * portSpacing + 16
+
+    signal moved(string id, real newX, real newY)
+    signal clicked(string id)
+    signal doubleClicked(string id)
+    signal portPressed(string nodeId, string portName, string portType, bool isOutput, real globalX, real globalY)
+    signal portReleased(string nodeId, string portName, string portType, bool isOutput, real globalX, real globalY)
+
+    x: nodeX
+    y: nodeY
+    width: minWidth
+    height: minHeight
+    radius: 8
+    color: selected ? Qt.lighter(Theme.paper, 1.1) : Theme.paper
+    border.color: selected ? groupColor() : Theme.border
+    border.width: selected ? 2 : 1
+
+    layer.enabled: true
+    layer.effect: null
+
+    function groupColor() {
+        switch (nodeType.split(".")[0]) {
+            case "metabuilder": return Theme.success
+            case "logic":       return Theme.warning
+            case "transform":
+            case "packagerepo": return "#FF9800"
+            case "sdl":
+            case "graphics":    return "#2196F3"
+            case "integration": return "#9C27B0"
+            case "io":          return "#00BCD4"
+            default:            return Theme.primary
+        }
+    }
+
+    // Header bar
+    Rectangle {
+        id: header
+        anchors.top: parent.top
+        anchors.left: parent.left
+        anchors.right: parent.right
+        height: headerHeight
+        radius: 8
+        color: groupColor()
+
+        // Square off bottom corners
+        Rectangle {
+            anchors.bottom: parent.bottom
+            anchors.left: parent.left
+            anchors.right: parent.right
+            height: parent.radius
+            color: parent.color
+        }
+
+        CText {
+            anchors.centerIn: parent
+            text: displayName || nodeName
+            color: "#FFFFFF"
+            variant: "body2"
+            font.bold: true
+            elide: Text.ElideRight
+            width: parent.width - 16
+            horizontalAlignment: Text.AlignHCenter
+        }
+    }
+
+    // Drag handler on the header
+    DragHandler {
+        id: dragHandler
+        target: nodeRoot
+        onActiveChanged: {
+            if (!active) {
+                nodeRoot.moved(nodeId, nodeRoot.x, nodeRoot.y)
+            }
+        }
+    }
+
+    // Click handler
+    TapHandler {
+        onTapped: nodeRoot.clicked(nodeId)
+        onDoubleTapped: nodeRoot.doubleClicked(nodeId)
+    }
+
+    // Input ports (left side)
+    Column {
+        anchors.left: parent.left
+        anchors.leftMargin: -portRadius
+        anchors.top: header.bottom
+        anchors.topMargin: 8
+        spacing: portSpacing - portRadius * 2
+
+        Repeater {
+            model: nodeInputs
+            delegate: Item {
+                width: portRadius * 2 + 60
+                height: portRadius * 2
+
+                Rectangle {
+                    id: inputPort
+                    width: portRadius * 2
+                    height: portRadius * 2
+                    radius: portRadius
+                    color: Theme.primary
+                    border.color: Theme.background
+                    border.width: 1
+
+                    MouseArea {
+                        anchors.fill: parent
+                        anchors.margins: -4
+                        hoverEnabled: true
+                        cursorShape: Qt.CrossCursor
+
+                        onPressed: function(mouse) {
+                            var global = inputPort.mapToItem(null, portRadius, portRadius)
+                            nodeRoot.portPressed(nodeId, modelData.name, modelData.type, false, global.x, global.y)
+                        }
+                        onReleased: function(mouse) {
+                            var global = inputPort.mapToItem(null, portRadius, portRadius)
+                            nodeRoot.portReleased(nodeId, modelData.name, modelData.type, false, global.x, global.y)
+                        }
+                    }
+                }
+
+                CText {
+                    anchors.left: inputPort.right
+                    anchors.leftMargin: 4
+                    anchors.verticalCenter: inputPort.verticalCenter
+                    text: modelData.displayName || modelData.name || "in"
+                    variant: "caption"
+                    font.pixelSize: 10
+                }
+            }
+        }
+    }
+
+    // Output ports (right side)
+    Column {
+        anchors.right: parent.right
+        anchors.rightMargin: -portRadius
+        anchors.top: header.bottom
+        anchors.topMargin: 8
+        spacing: portSpacing - portRadius * 2
+
+        Repeater {
+            model: nodeOutputs
+            delegate: Item {
+                width: portRadius * 2 + 60
+                height: portRadius * 2
+                layoutDirection: Qt.RightToLeft
+
+                CText {
+                    anchors.right: outputPort.left
+                    anchors.rightMargin: 4
+                    anchors.verticalCenter: outputPort.verticalCenter
+                    text: modelData.displayName || modelData.name || "out"
+                    variant: "caption"
+                    font.pixelSize: 10
+                    horizontalAlignment: Text.AlignRight
+                }
+
+                Rectangle {
+                    id: outputPort
+                    anchors.right: parent.right
+                    width: portRadius * 2
+                    height: portRadius * 2
+                    radius: portRadius
+                    color: Theme.success
+                    border.color: Theme.background
+                    border.width: 1
+
+                    MouseArea {
+                        anchors.fill: parent
+                        anchors.margins: -4
+                        hoverEnabled: true
+                        cursorShape: Qt.CrossCursor
+
+                        onPressed: function(mouse) {
+                            var global = outputPort.mapToItem(null, portRadius, portRadius)
+                            nodeRoot.portPressed(nodeId, modelData.name, modelData.type, true, global.x, global.y)
+                        }
+                        onReleased: function(mouse) {
+                            var global = outputPort.mapToItem(null, portRadius, portRadius)
+                            nodeRoot.portReleased(nodeId, modelData.name, modelData.type, true, global.x, global.y)
+                        }
+                    }
+                }
+            }
+        }
+    }
+}
--- a/frontends/qt6/qmllib/MetaBuilder/qmldir
+++ b/frontends/qt6/qmllib/MetaBuilder/qmldir
@@ -4,3 +4,4 @@ HeroSection 1.0 HeroSection.qml
 FeatureCard 1.0 FeatureCard.qml
 StatusCard 1.0 StatusCard.qml
 ContactForm 1.0 ContactForm.qml
+WorkflowNode 1.0 WorkflowNode.qml
--- a/frontends/qt6/src/NodeRegistry.cpp
+++ b/frontends/qt6/src/NodeRegistry.cpp
@@ -0,0 +1,111 @@
+#include "NodeRegistry.h"
+
+#include <QFile>
+#include <QJsonDocument>
+#include <QDebug>
+#include <algorithm>
+
+NodeRegistry::NodeRegistry(QObject *parent)
+    : QObject(parent)
+{
+}
+
+QVariantList NodeRegistry::nodeTypes() const
+{
+    QVariantList list;
+    for (auto it = m_nodeTypes.constBegin(); it != m_nodeTypes.constEnd(); ++it) {
+        list.append(it.value().toVariantMap());
+    }
+    return list;
+}
+
+void NodeRegistry::loadRegistry(const QString &path)
+{
+    QFile file(path);
+    if (!file.open(QIODevice::ReadOnly | QIODevice::Text)) {
+        m_lastError = QStringLiteral("Cannot open registry file: ") + path;
+        qWarning() << "NodeRegistry:" << m_lastError;
+        emit errorOccurred(m_lastError);
+        return;
+    }
+
+    QJsonParseError parseErr;
+    const QJsonDocument doc = QJsonDocument::fromJson(file.readAll(), &parseErr);
+    file.close();
+
+    if (parseErr.error != QJsonParseError::NoError) {
+        m_lastError = QStringLiteral("JSON parse error: ") + parseErr.errorString();
+        qWarning() << "NodeRegistry:" << m_lastError;
+        emit errorOccurred(m_lastError);
+        return;
+    }
+
+    parseRegistry(doc.object());
+
+    m_loaded = true;
+    emit loadedChanged();
+    emit nodeTypesChanged();
+    qDebug() << "NodeRegistry: loaded" << m_nodeTypes.count() << "node types in"
+             << m_groups.count() << "groups from" << path;
+}
+
+void NodeRegistry::parseRegistry(const QJsonObject &root)
+{
+    m_nodeTypes.clear();
+    m_groups.clear();
+
+    const QJsonArray types = root.value(QStringLiteral("nodeTypes")).toArray();
+    QSet<QString> groupSet;
+
+    for (const QJsonValue &val : types) {
+        const QJsonObject obj = val.toObject();
+        const QString name = obj.value(QStringLiteral("name")).toString();
+        if (name.isEmpty())
+            continue;
+
+        m_nodeTypes.insert(name, obj);
+
+        const QString group = obj.value(QStringLiteral("group")).toString();
+        if (!group.isEmpty())
+            groupSet.insert(group);
+    }
+
+    m_groups = groupSet.values();
+    m_groups.sort();
+}
+
+QVariantMap NodeRegistry::nodeType(const QString &name) const
+{
+    if (!m_nodeTypes.contains(name))
+        return {};
+    return m_nodeTypes.value(name).toVariantMap();
+}
+
+QVariantList NodeRegistry::nodesByGroup(const QString &group) const
+{
+    QVariantList list;
+    for (auto it = m_nodeTypes.constBegin(); it != m_nodeTypes.constEnd(); ++it) {
+        if (it.value().value(QStringLiteral("group")).toString() == group)
+            list.append(it.value().toVariantMap());
+    }
+    return list;
+}
+
+QVariantList NodeRegistry::searchNodes(const QString &query) const
+{
+    if (query.isEmpty())
+        return nodeTypes();
+
+    const QString lower = query.toLower();
+    QVariantList list;
+    for (auto it = m_nodeTypes.constBegin(); it != m_nodeTypes.constEnd(); ++it) {
+        const QJsonObject &obj = it.value();
+        const QString name = obj.value(QStringLiteral("name")).toString().toLower();
+        const QString displayName = obj.value(QStringLiteral("displayName")).toString().toLower();
+        const QString desc = obj.value(QStringLiteral("description")).toString().toLower();
+
+        if (name.contains(lower) || displayName.contains(lower) || desc.contains(lower))
+            list.append(obj.toVariantMap());
+    }
+    return list;
+}
--- a/frontends/qt6/src/NodeRegistry.h
+++ b/frontends/qt6/src/NodeRegistry.h
@@ -0,0 +1,50 @@
+#ifndef NODEREGISTRY_H
+#define NODEREGISTRY_H
+
+#include <QObject>
+#include <QJsonObject>
+#include <QJsonArray>
+#include <QString>
+#include <QStringList>
+#include <QMap>
+#include <QVariantList>
+
+class NodeRegistry : public QObject
+{
+    Q_OBJECT
+    Q_PROPERTY(QVariantList nodeTypes READ nodeTypes NOTIFY nodeTypesChanged)
+    Q_PROPERTY(QStringList groups READ groups NOTIFY nodeTypesChanged)
+    Q_PROPERTY(int nodeCount READ nodeCount NOTIFY nodeTypesChanged)
+    Q_PROPERTY(bool loaded READ isLoaded NOTIFY loadedChanged)
+    Q_PROPERTY(QString lastError READ lastError NOTIFY errorOccurred)
+
+public:
+    explicit NodeRegistry(QObject *parent = nullptr);
+
+    QVariantList nodeTypes() const;
+    QStringList groups() const { return m_groups; }
+    int nodeCount() const { return m_nodeTypes.count(); }
+    bool isLoaded() const { return m_loaded; }
+    QString lastError() const { return m_lastError; }
+
+public slots:
+    void loadRegistry(const QString &path);
+    QVariantMap nodeType(const QString &name) const;
+    QVariantList nodesByGroup(const QString &group) const;
+    QVariantList searchNodes(const QString &query) const;
+
+signals:
+    void nodeTypesChanged();
+    void loadedChanged();
+    void errorOccurred(const QString &error);
+
+private:
+    void parseRegistry(const QJsonObject &root);
+
+    QMap<QString, QJsonObject> m_nodeTypes;
+    QStringList m_groups;
+    bool m_loaded = false;
+    QString m_lastError;
+};
+
+#endif