Novolis.Avalonia.Cad (Primitives namespace + LLM session)

name: Avalonia Cad library overview: Add packable Novolis.Avalonia.Cad (editor + Raylib preview/export) with Cad DTOs under namespace Novolis.Cad.Primitives only, plus Sins-style localhost HTTP/TCP session endpoints so LLMs drive the same executor as the UI. todos:

• id: avalonia-cad-pkg

content: Create Novolis.Avalonia.Cad packable project; Primitives/ folder with namespace Novolis.Cad.Primitives only (not a separate package) status: completed

• id: avalonia-cad-editor

content: Lift CadDraftViewport, CadModelRenderer, tools/commands, CadEditorSurface; all UI mutations go through CadBridgeService.Execute status: completed

• id: avalonia-cad-preview

content: Add CadPreviewControl + CadViewportExporter (plan PNG, Raylib PNG, multi-view tour, phys) as session actions too status: completed

• id: cad-session-llm

content: ICadSession + CadBridgeService + CadSessionSurface HTTP/TCP (Sins pattern); action parity with UI; snapshot/actions/command/events status: completed

• id: wire-consumers

content: Thin DraftStudio and CalypsoCad onto Novolis.Avalonia.Cad; AttachAll session + keep glass AgentHost in EXEs status: completed

• id: registry-verify

content: packages.json, slnx, map regen; policy scripts; smoke UI + HTTP snapshot/command status: completed isProject: false

Goal

One shared Avalonia CAD NuGet for DraftStudio (editor) and CalypsoCad (preview), with unified plan/Raylib export, plus a Sins-style domain session (localhost HTTP + TCP JSONL) so LLMs can control and read CAD with action parity to the UI.

CAD interchange types use namespace `Novolis.Cad.Primitives` in a special folder inside the Cad project. No separate Novolis.Cad.Primitives NuGet yet.

“Drawing export” = plan RenderTargetBitmap (`DraftArtifactDumper`). Raylib export = `TrySaveLastPresentedFramePng` + Calypso wait loop (`ViewportPngExporter`).

flowchart TB
  subgraph clients [Clients]
    UI[Avalonia UI]
    LLM[LLM HTTP or TCP]
    Glass[AgentHost ui glass]
  end
  subgraph cad [Novolis.Avalonia.Cad]
    Bridge[CadBridgeService ICadSession]
    Surface[CadSessionSurface]
    Editor[CadEditorSurface / Preview]
    Prim[Primitives namespace]
  end
  UI -->|"Execute same path"| Bridge
  LLM --> Surface
  Surface --> Bridge
  Bridge --> Editor
  Bridge --> Prim
  Glass -.->|separate LocalIpc| UI

Package layout (locked)

Inside that project:

• Primitives/ — DTOs under `Novolis.Cad.Primitives` (compiled into Avalonia.Cad assembly)
• UI: Novolis.Avalonia.Cad (editor, preview, exporter)
• Session: Novolis.Avalonia.Cad.Session (hosts + DTOs + bridge) — still same assembly/package

Deferred: extract Primitives NuGet / novolis-cad repo. Consumers PackageReference `Novolis.Avalonia.Cad` only.

Register in `.novolis/packages.json`; regen platform map. Version 2026.1.*.

Do not reuse Novolis.Game.Session voyage DTOs; copy the host pattern from `SessionHttpHost` / `SessionTcpJsonlHost` / `SessionSurface` with Cad-specific ports, env, markers, and DTOs.

1. Namespace `Novolis.Cad.Primitives` (folder only)

Lift DraftStudio `Models/` + align Calypso `CadModels.cs`: document/entities/layers/phys + JSON load/save per `cadjson.md`.

2. Editor + preview (UI)

• CadDraftViewport, CadModelRenderer, CadToolController, command bus
• CadEditorSurface — draft/model shell
• CadPreviewControl — Raylib lifecycle + FrameRendering
• CadViewportExporter — plan PNG, model PNG, view tour, phys

Parity rule: toolbar / tools / command bar / export buttons must call `CadBridgeService.Execute` (or thin wrappers that only build a CadCommandDto). No parallel mutation paths.

3. LLM session surface (Sins pattern)

Mirror Sins dual-channel model:

Contract (`ICadSession`)

Same shape as `IGameSession`:

• Hello() / Snapshot() / Actions() / Execute(CadCommandDto)
• Events: Changed, ActionResult (and optional decision-style hints)

`CadBridgeService` implements ICadSession: owns document session, tools, selection, exporter; UI and transports both use it.

Transports

• CadSessionHttpHost — HttpListener loopback (no Kestrel), CORS as in Sins
• CadSessionTcpJsonlHost — one JSON object per line
• CadSessionSurface.AttachAll(bridge) / TryAttachFromEnvironment

Defaults (Cad-specific, avoid clashing with Sins 18765/18766):

• HTTP http://127.0.0.1:18775
• TCP 127.0.0.1:18776
• Env: NOVOLIS_CAD_SESSION, _HTTP, _HTTP_PORT, _TCP, _TCP_PORT
• Markers under %TEMP% e.g. novolis-cad-session.http / .tcp

HTTP routes (parity with Sins)

Envelope: { "ok": true, "result": ... } camelCase.

Snapshot / actions (LLM data)

Snapshot (illustrative): document name/path, dirty, entityCount, selection ids, active tool, viewMode (draft/model), drawElevation, units, lastAction, recent export paths.

Actions list: { id, label, enabled, disabledReason? }[] — must match what the UI can do.

Command: { "actionId": "...", ...typed fields } → { ok, actionId, message, errorCode?, snapshot? }.

Action catalog (UI parity — locked minimum)

Document/edit: new, open, save, undo, redo, deleteSelection, select, fit Tools: setTool (line/circle/rect/spline/select), setViewMode (draft/model), setElevation, setSnap, setGrid Geometry DSL (optional thin): runCommand for existing Line(...) / Box(...) text Export: exportPlanPng, exportModelPng, exportPreviewPng, exportViewTour, exportPhys Preview (Calypso host may extend): setOrbit / app-specific view ids via properties bag if needed

Host apps may register extra action handlers on the bridge for ship-specific preview acts without forking the HTTP host.

4. Consumer wire-up

var bridge = new CadBridgeService(/* document + editor + exporter */);
_ = CadSessionSurface.AttachAll(bridge);              // LLM HTTP/TCP
AgentHost.TryAttachFromEnvironment(mainWindow);     // glass only (EXE)
// UI buttons → bridge.Execute(...)

DraftStudio / CalypsoCad: PackageReference Novolis.Avalonia.Cad only; delete duplicated models/exporters; keep product chrome + AgentProperties ids (draft.* / calypso.*).

5. Out of scope

• Separate Novolis.Cad.Primitives package / novolis-cad repo
• Stuffing CAD into Novolis.Game.Session DTOs
• SketchControl → Cad; walkthrough/ffmpeg inside Cad NuGet
• Replacing glass AgentHost with HTTP (both coexist like Sins)

6. Verification

• Unit: Primitives JSON round-trip; CadBridgeService.Execute action matrix without GLFW
• Integration smoke: start DraftStudio → GET /session/snapshot → POST /session/command (setTool / exportPlanPng) and confirm UI state matches
• Policy scripts + ProjectRef local build; GPR publish before CI consumers without ProjectRef