feat(create): manifest viewer — read-only MDI widget for silo/manifest.json (#38)

Add SiloManifestViewer widget that opens in an MDI subwindow when the
user double-clicks the Manifest node in the Silo tree. Displays all
manifest.json fields in a read-only QFormLayout with copy buttons for
Part UUID and Silo Instance.

New files:
- silo_viewers.py: SiloManifestViewer widget + create_viewer_widget()
  factory with _VIEWER_REGISTRY for future viewer classes

Modified files:
- silo_viewproviders.py: doubleClicked() wired to open MDI subwindow
  with deduplication via widget objectName()
- CMakeLists.txt: add silo_viewers.py to install list

Closes #38

src/Mod/Create/CMakeLists.txt

@@ -25,6 +25,7 @@ install(
         silo_document.py
         silo_objects.py
         silo_tree.py
+        silo_viewers.py
         silo_viewproviders.py
         update_checker.py
         ${CMAKE_CURRENT_BINARY_DIR}/version.py

src/Mod/Create/silo_viewers.py

@@ -0,0 +1,151 @@
+"""
+silo_viewers.py — Read-only MDI viewer widgets for Silo tree leaf nodes.
+
+Each viewer is a plain QWidget suitable for embedding in an MDI subwindow.
+The ``create_viewer_widget`` factory routes a SiloViewerObject to the
+appropriate viewer class based on its SiloPath property.
+"""
+
+import json
+
+import FreeCAD
+from PySide import QtCore, QtWidgets
+
+# ---------------------------------------------------------------------------
+#   Manifest Viewer
+# ---------------------------------------------------------------------------
+
+_MANIFEST_FIELDS = [
+    ("Part UUID", "part_uuid", True),
+    ("Silo Instance", "silo_instance", True),
+    ("Revision Hash", "revision_hash", False),
+    ("KC Version", "kc_version", False),
+    ("Created", "created_at", False),
+    ("Modified", "modified_at", False),
+    ("Created By", "created_by", False),
+]
+
+
+class SiloManifestViewer(QtWidgets.QWidget):
+    """Read-only form displaying ``silo/manifest.json`` fields."""
+
+    WINDOW_TITLE = "Silo \u2014 Manifest"
+
+    def __init__(self, obj, parent=None):
+        super().__init__(parent)
+        self.setObjectName(f"SiloViewer_{obj.Name}")
+        self._build_ui(obj.RawContent)
+
+    # -- layout --------------------------------------------------------------
+
+    def _build_ui(self, raw_content):
+        try:
+            data = json.loads(raw_content)
+        except Exception:
+            data = {}
+
+        outer = QtWidgets.QVBoxLayout(self)
+        outer.setContentsMargins(16, 16, 16, 16)
+        outer.setSpacing(12)
+
+        title = QtWidgets.QLabel("Silo Manifest")
+        font = title.font()
+        font.setPointSize(font.pointSize() + 2)
+        font.setBold(True)
+        title.setFont(font)
+        outer.addWidget(title)
+
+        line = QtWidgets.QFrame()
+        line.setFrameShape(QtWidgets.QFrame.HLine)
+        line.setFrameShadow(QtWidgets.QFrame.Sunken)
+        outer.addWidget(line)
+
+        form = QtWidgets.QFormLayout()
+        form.setLabelAlignment(QtCore.Qt.AlignRight | QtCore.Qt.AlignVCenter)
+        form.setHorizontalSpacing(16)
+        form.setVerticalSpacing(8)
+        outer.addLayout(form)
+
+        for label_text, key, copyable in _MANIFEST_FIELDS:
+            raw_val = str(data.get(key, "") or "")
+            display_val = _format_value(key, raw_val)
+            _add_row(form, label_text, display_val, raw_val, copyable)
+
+        outer.addStretch()
+
+    # -- no state to serialize -----------------------------------------------
+
+
+# ---------------------------------------------------------------------------
+#   Helpers
+# ---------------------------------------------------------------------------
+
+
+def _format_value(key, value):
+    """Format a manifest value for display."""
+    if not value:
+        return "\u2014"  # em-dash
+    if key in ("created_at", "modified_at"):
+        try:
+            s = str(value).replace("Z", "").replace("T", " ")
+            if len(s) >= 16:
+                s = s[:16]
+            return s + " UTC"
+        except Exception:
+            pass
+    return str(value)
+
+
+def _add_row(form, label_text, display_val, raw_val, copyable):
+    """Add a single row to the form layout."""
+    value_label = QtWidgets.QLabel(display_val)
+    value_label.setTextInteractionFlags(QtCore.Qt.TextSelectableByMouse)
+
+    if copyable and raw_val:
+        row = QtWidgets.QWidget()
+        row_layout = QtWidgets.QHBoxLayout(row)
+        row_layout.setContentsMargins(0, 0, 0, 0)
+        row_layout.setSpacing(4)
+        row_layout.addWidget(value_label)
+
+        btn = QtWidgets.QToolButton()
+        btn.setText("\u29c9")  # ⧉
+        btn.setFixedWidth(24)
+        btn.setToolTip(f"Copy {label_text}")
+        btn.clicked.connect(
+            lambda checked=False, v=raw_val: QtWidgets.QApplication.clipboard().setText(
+                v
+            )
+        )
+        row_layout.addWidget(btn)
+        row_layout.addStretch()
+        form.addRow(label_text + ":", row)
+    else:
+        form.addRow(label_text + ":", value_label)
+
+
+# ---------------------------------------------------------------------------
+#   Viewer factory
+# ---------------------------------------------------------------------------
+
+_VIEWER_REGISTRY = {
+    "silo/manifest.json": SiloManifestViewer,
+}
+
+
+def create_viewer_widget(obj):
+    """Route a Silo tree node to the appropriate viewer widget.
+
+    Returns a QWidget ready for MDI embedding, or None if no viewer
+    is registered for this node's SiloPath.
+    """
+    cls = _VIEWER_REGISTRY.get(obj.SiloPath)
+    if cls is None:
+        return None
+    try:
+        return cls(obj)
+    except Exception as exc:
+        FreeCAD.Console.PrintWarning(
+            f"silo_viewers: failed to create viewer for {obj.SiloPath!r}: {exc}\n"
+        )
+        return None

src/Mod/Create/silo_viewproviders.py

@@ -63,8 +63,44 @@ class SiloViewerViewProvider:
             return ""
 
     def doubleClicked(self, vobj):
-        """Phase 1: no action on double-click."""
-        return False
+        """Open a read-only MDI viewer for this silo node."""
+        try:
+            import FreeCADGui
+            from PySide import QtWidgets
+            from silo_viewers import create_viewer_widget
+
+            obj = vobj.Object
+            widget = create_viewer_widget(obj)
+            if widget is None:
+                return False
+
+            mw = FreeCADGui.getMainWindow()
+            mdi = mw.findChild(QtWidgets.QMdiArea)
+            if mdi is None:
+                return False
+
+            # Reuse existing subwindow if already open for this object
+            target_name = widget.objectName()
+            for sw in mdi.subWindowList():
+                if sw.widget() and sw.widget().objectName() == target_name:
+                    widget.deleteLater()
+                    mdi.setActiveSubWindow(sw)
+                    sw.show()
+                    return True
+
+            sw = mdi.addSubWindow(widget)
+            sw.setWindowTitle(getattr(widget, "WINDOW_TITLE", "Silo Viewer"))
+            sw.show()
+            mdi.setActiveSubWindow(sw)
+            return True
+
+        except Exception as exc:
+            import FreeCAD
+
+            FreeCAD.Console.PrintWarning(
+                f"silo_viewproviders: doubleClicked failed: {exc}\n"
+            )
+            return False
 
     def setupContextMenu(self, vobj, menu):
         """Phase 1: no context menu items."""