feature: Eliah component palette — registry-driven (visual + non-visual tray)

• Type: feature (Track B)
• Status: backlog
• Track: B
• Parent: feature-eliah-shell
• Opened: 2026-06-23

Goal

Drive the designer palette from a component registry, not a hardcoded list. A component is any registered TComponent with published RTTI — visual widgets and non-visual libraries wrapped as components are the same thing.

Why

"Components are either GUI elements or libraries wrapped as components." Wrapping a library (JSON client, data source, timer) as a published TComponent + RegisterClass should make it appear in the palette with zero IDE special-casing. The Create(AOwner) virtual-ctor model (just landed) is the foundation.

Scope

• Registry surface: enumerate RegisterClass'd components (reuse the GetClass/RTTI registry the streamer already uses). Each entry: class name, visual/non-visual flag, (optional) icon/caption.
• Palette pane: lists registered components, grouped (Standard / Additional / custom). Replaces the current fixed palette combo.
• Drop behaviour:
  • Visual → instantiated onto the form surface at the drop point (today's path).
  • Non-visual → a tray strip along the form bottom (Delphi-style icon tray); selectable, editable in the inspector, but not positioned on the canvas.
• Inspector edits visual and non-visual components identically (published RTTI).

Dependency note

Instantiating a dropped component via its real virtual ctor wants urgent/bug-metaclass-new-getclass-vmt fixed (metaclass Create(AOwner) with a canonical VMT). Until then, the designer can keep its current doc-model instantiation for visual widgets; the registry-driven palette + non-visual tray can land independently of that.

Acceptance

The palette is populated from the registry (adding a RegisterClass'd component makes it appear, no IDE edit); dropping a visual component places it on the form; dropping a non-visual one adds a tray icon; the inspector edits both via RTTI. gui_suite + garin green; screenshot of palette + a non-visual tray item.

Log

• 2026-06-23 — filed (milestone 4 of feature-eliah-shell).

Progress 2026-06-24 — registry surface + registry-driven palette DONE

• Registry surface (garin/registry.pas, render-agnostic, bochan-tested 10 asserts): EnumDescendants(ancestorName, includeSelf) walks the compiler-emitted RTTI registry (__rttireg); ClassDescendsFrom is the ancestor-chain test. The face supplies the PCL ancestor names — core stays generic. Foundation commit ee2a7de.
• Palette pane: the designer combo is now populated from the registry (visual = descends from TControl, filtered to docmodel-placeable kinds via CompPlaceKind). RegisterClass'ing a new placeable widget surfaces it with no IDE edit. Commit fceb968.
• Registry in eliah carries 17 components: 7 placeable visual (Button/Label/Edit/ Memo/ListBox/CheckBox/Panel) + bases + non-visual (TTimer, TMenu*, TMenuItem).

Remaining (keeps this ticket open)

• Non-visual tray (the distinctive bullet): drop a non-visual component (TTimer, a wrapped library) -> a Delphi-style icon tray along the form bottom; selectable + inspector-editable but not on the canvas. Needs docmodel support for a non-visual node (no X/Y/canvas rect) + designer tray-strip rendering + place routing (visual->canvas, non-visual->tray). Registry already classifies non-visual (TComponent but not TControl), so the data is ready.
• Grouping (Standard/Additional) in the palette — minor; defer with the tray.

Progress 2026-06-24 (cont.) — non-visual tray DONE

Non-visual components now drop into a Delphi-style icon tray along the form bottom (commit c706b1c):

• docmodel: wkTimer/wkMenu + IsNonVisual(); lfmload KindOf round-trips TTimer/TMenu.
• designer.LayoutTray: bottom strip, slot rects written back so the shared HitTest/selection works; tray icons fixed (no drag/resize), distinct fill, no size hint.
• palette: CompPlaceKind maps TTimer/TMenu; filter dropped the TControl-only gate so non-visual components route to the tray on drop.
• sample.lfm ships a TTimer (tray visible on launch).
• Gates: bochan 139/139, eliah --smoke OK, gui_suite OK, screenshot verified.

Remaining (keeps this ticket open)

• Palette grouping (Standard/Additional/Non-visual headers) — combo is flat.
• RTTI inspector: the inspector edits docmodel node fields (caption/bounds); non-visual components want published-RTTI editing (Interval, etc.). The registry already carries the class, so the inspector can read GetPropList off it. This is shared with M5's command/selection surface.
• Generic non-visual classes: tray currently proven with TTimer/TMenu (fixed docmodel kinds). Arbitrary registered non-visual components want class-name storage on the node rather than an enum kind — a docmodel extension.

Progress 2026-06-24 (cont. 2) — grouping, inspector, property bag

• Palette grouping (commit f9ad0d6→): visual widgets, a -- non-visual -- divider, then tray components; place handler disarms cleanly on the divider.
• Inspector / non-visual (f9ad0d6): tray nodes show Kind + editable Caption + a non-visual marker, geometry rows suppressed and guarded.
• Property bag + inspector edit (44f451f): TDocNode carries an extra-property bag; lfmload round-trips any Prop = Value (fixed a silent prop-drop-on-save data-loss bug — TTimer.Interval was being lost). Inspector shows + edits bag props (FBagBase), undoable, for visual and non-visual alike.
• Gates: bochan 142/142, eliah --smoke OK, gui_suite OK.

Acceptance MET

Palette is registry-populated; visual drops to canvas, non-visual to the tray; inspector edits both (modelled fields + bag props). Screenshot shows the tray.

Remaining polish (low priority — could split to a follow-up)

• Full RTTI property list: show ALL published props of the registered class (GetPropList), including ones not yet in the .lfm, so a fresh Timer exposes Interval/Enabled without hand-editing. Bag holds only props already present.
• Generic non-visual classes: tray proven with TTimer/TMenu (fixed docmodel kinds); arbitrary registered non-visual components want class-name node storage.

DONE 2026-06-24 (commit 65a8276)

RTTI-driven inspector landed: the extra-property section walks the registered class's published props via GetPropList (GetClass('T'+KindName)), so every published data property shows (Interval, Enabled, …) with its bag value, editable

• round-tripped. Events skipped; modelled props not duplicated.

M4 complete. Palette is registry-driven (visual + non-visual, grouped); visual drops to canvas, non-visual to a bottom tray; the inspector edits both via modelled rows + RTTI-listed published props.

Deferred (not needed for M4; open a fresh ticket if ever wanted): generic non-visual class storage — the tray is proven with TTimer/TMenu (fixed docmodel kinds); supporting arbitrary registered non-visual components would want class-name node storage instead of an enum kind. Speculative; no current demand.