From 8204de81c40d8a173ba36becf29b93c8e6271167 Mon Sep 17 00:00:00 2001
From: Agent Zero <agent@media-on.de>
Date: Wed, 26 Aug 2026 23:14:26 +0200
Subject: [PATCH] task(A4.2): migrate rect tool to v2 plugin

---
 .../src/plugins/builtin/core-drawing/index.ts | 77 ++++++++++++++++++-
 frontend/tests/pilotTools.test.ts             | 40 ++++++++++
 2 files changed, 113 insertions(+), 4 deletions(-)

diff --git a/frontend/src/plugins/builtin/core-drawing/index.ts b/frontend/src/plugins/builtin/core-drawing/index.ts
index b94538d..caab46b 100644
--- a/frontend/src/plugins/builtin/core-drawing/index.ts
+++ b/frontend/src/plugins/builtin/core-drawing/index.ts
@@ -16,6 +16,8 @@ const uid = (prefix: string): string =>
 
 /** Startpunkt der laufenden Linie (nur innerhalb einer down→up-Sitzung gesetzt). */
 let lineStart: Pt | null = null;
+/** Startpunkt des laufenden Rechtecks (A4.2). */
+let rectStart: Pt | null = null;
 
 function buildLine(start: Pt, end: Pt, ctx: FullToolContext): CADElement {
   const stroke = (ctx.options.strokeColor as string | undefined) ?? '#e0e0f0';
@@ -32,6 +34,25 @@ function buildLine(start: Pt, end: Pt, ctx: FullToolContext): CADElement {
   } as unknown as CADElement;
 }
 
+function buildRect(cornerA: Pt, cornerB: Pt, ctx: FullToolContext): CADElement {
+  const stroke = (ctx.options.strokeColor as string | undefined) ?? '#e0e0f0';
+  const layerId = (ctx.options.layerId as string | undefined) ?? 'layer-0';
+  const minX = Math.min(cornerA.x, cornerB.x);
+  const minY = Math.min(cornerA.y, cornerB.y);
+  const w = Math.abs(cornerB.x - cornerA.x);
+  const h = Math.abs(cornerB.y - cornerA.y);
+  return {
+    id: uid('rect'),
+    type: 'rect',
+    layerId,
+    x: minX + w / 2,          // BBox-Zentrum (Legacy-Konvention)
+    y: minY + h / 2,
+    width: w,
+    height: h,
+    properties: { stroke, strokeWidth: 1 },
+  } as unknown as CADElement;
+}
+
 /**
  * line-Werkzeug: down setzt Startpunkt, move zeigt Live-Vorschau,
  * up committet via doc.transact (1 Linie = 1 Undo-Schritt).
@@ -80,16 +101,64 @@ export const lineTool: ToolExtensionV2 = {
   },
 };
 
-/** V2-Plugin: Kern-Zeichenwerkzeuge (Pilot: nur line). */
+/**
+ * rect-Werkzeug (A4.2): down setzt Ecke, move zeigt BBox-Vorschau,
+ * up committet via doc.transact. Portiert aus Legacy case 'rect'
+ * (BBox-Konvention: x/y = Zentrum, width/height absolut).
+ */
+export const rectTool: ToolExtensionV2 = {
+  manifest: {
+    id: 'rect',
+    label: 'Rechteck',
+    icon: '\u25ad',
+    ribbonTab: 'canvas',
+    tags: ['basic'],
+    description: 'Zieht ein Rechteck auf (Klick Ecke, Klick Gegenecke)',
+  },
+  optionsSchema: [
+    { key: 'strokeColor', label: 'Farbe', type: 'color' },
+  ],
+  handlers: {
+    down(e, ctx) {
+      rectStart = e.world;
+      ctx.setStatus(`Rechteck ab (${rectStart.x.toFixed(0)}, ${rectStart.y.toFixed(0)}) – Gegenecke wählen`);
+    },
+    move(e, ctx) {
+      if (!rectStart) return;
+      ctx.setPreview?.(buildRect(rectStart, e.world, ctx));
+    },
+    up(e, ctx) {
+      const c = ctx as FullToolContext;
+      if (!rectStart || !c.doc) {
+        rectStart = null;
+        return;
+      }
+      const el = buildRect(rectStart, e.world, c);
+      c.doc.transact(() => {
+        c.doc!.addElement(el);
+      });
+      rectStart = null;
+      ctx.setPreview?.(null);
+      ctx.setStatus(`Rechteck erstellt (${el.id})`);
+    },
+    cancel(ctx) {
+      rectStart = null;
+      ctx.setPreview?.(null);
+      ctx.setStatus('Rechteck abgebrochen');
+    },
+  },
+};
+
+/** V2-Plugin: Kern-Zeichenwerkzeuge (Pilot: line; A4.2: rect). */
 export const coreDrawingPlugin: PluginV2 = {
   manifest: {
     id: 'core-drawing',
     name: 'Zeichnen (Kern)',
-    version: '1.0.0',
+    version: '1.1.0',
     author: 'web-cad team',
-    description: 'Grundlegende Zeichenwerkzeuge (V2-Pilot: Linie).',
+    description: 'Grundlegende Zeichenwerkzeuge (V2: Linie, Rechteck).',
     category: 'tools',
     enabledByDefault: true,
   },
-  tools: [lineTool],
+  tools: [lineTool, rectTool],
 };
diff --git a/frontend/tests/pilotTools.test.ts b/frontend/tests/pilotTools.test.ts
index c4d9bb4..4d13936 100644
--- a/frontend/tests/pilotTools.test.ts
+++ b/frontend/tests/pilotTools.test.ts
@@ -80,6 +80,46 @@ describe('A3 pilot: line tool', () => {
   });
 });
 
+describe('A4.2 pilot: rect tool', () => {
+  it('erzeugt Rechteck mit BBox-Konvention; ein undo entfernt es', () => {
+    const { ydoc } = createInMemoryDoc();
+    const doc = new CADDocument(ydoc);
+    const ctx = makeCtx({ doc });
+    const rect = coreDrawingPlugin.tools?.find((t) => t.manifest.id === 'rect');
+    expect(rect).toBeDefined();
+
+    rect!.handlers.down!(pe(10, 10), ctx);
+    rect!.handlers.move!(pe(110, 60), ctx);
+    expect(ctx.previews.length).toBe(1);       // Live-Vorschau
+    rect!.handlers.up!(pe(110, 60), ctx);
+
+    const all = doc.getAllElements();
+    expect(all.length).toBe(1);
+    expect(all[0].type).toBe('rect');
+    // Legacy-BBox-Konvention: Zentrum zwischen beiden Ecken
+    expect(all[0].x).toBe(60);
+    expect(all[0].y).toBe(35);
+    expect(all[0].width).toBe(100);
+    expect(all[0].height).toBe(50);
+
+    expect(doc.undo()).toBe(true);
+    expect(doc.getAllElements().length).toBe(0);
+  });
+
+  it('cancel verwirft das laufende Rechteck', () => {
+    const { ydoc } = createInMemoryDoc();
+    const doc = new CADDocument(ydoc);
+    const ctx = makeCtx({ doc });
+    const rect = coreDrawingPlugin.tools!.find((t) => t.manifest.id === 'rect')!;
+
+    rect.handlers.down!(pe(5, 5), ctx);
+    rect.handlers.cancel!(ctx);
+    rect.handlers.up!(pe(50, 50), ctx);
+
+    expect(doc.getAllElements().length).toBe(0);
+  });
+});
+
 describe('A3 pilot: select tool', () => {
   function makeBridge(elements: CADElement[]) {
     let ids: string[] = [];