fix: mini mindmap layout (#9276)

Fixes [BS-2197](https://linear.app/affine-design/issue/BS-2197/ai-生成-mindmap-预览异常)

blocksuite/presets/src/__tests__/edgeless/mini-mindmap.spec.ts

@@ -12,9 +12,26 @@ import { wait } from '../utils/common.js';
 import { getDocRootBlock } from '../utils/edgeless.js';
 import { setupEditor } from '../utils/setup.js';
 
-describe('mind map', () => {
+describe('mini mindmap preview', () => {
   let edgeless!: EdgelessRootBlockComponent;
 
+  const createPreview = (host: EditorHost, answer: string) => {
+    const mindmapPreview = new MiniMindmapPreview();
+
+    mindmapPreview.answer = answer;
+    mindmapPreview.host = host;
+    mindmapPreview.ctx = {
+      get() {
+        return {};
+      },
+      set() {},
+    };
+
+    document.body.append(mindmapPreview);
+
+    return mindmapPreview;
+  };
+
   beforeEach(async () => {
     const cleanup = await setupEditor('edgeless');
 
@@ -25,7 +42,7 @@ describe('mind map', () => {
     return cleanup;
   });
 
-  test('mind map preview', async () => {
+  test('mini mindmap basic', async () => {
     const mindmapAnswer = `
   - Mindmap
     - Node 1
@@ -36,74 +53,65 @@ describe('mind map', () => {
       - Node 2.2
   `;
 
-    const createPreview = (
-      host: EditorHost,
-      answer: string = mindmapAnswer
-    ) => {
-      const mindmapPreview = new MiniMindmapPreview();
-
-      mindmapPreview.answer = answer;
-      mindmapPreview.host = host;
-      mindmapPreview.ctx = {
-        get() {
-          return {};
-        },
-        set() {},
-      };
-
-      document.body.append(mindmapPreview);
-
-      return mindmapPreview;
-    };
-
-    const miniMindMapPreview = createPreview(window.editor.host!);
+    const miniMindMapPreview = createPreview(
+      window.editor.host!,
+      mindmapAnswer
+    );
     await wait(50);
     const miniMindMapSurface = miniMindMapPreview.renderRoot.querySelector(
       'mini-mindmap-surface-block'
     ) as MindmapSurfaceBlock;
 
-    expect(miniMindMapSurface).not.toBeNull();
+    // model-related properties
+    expect(miniMindMapPreview.mindmapId).toBeDefined();
+    expect(miniMindMapPreview.portalHost).toBeDefined();
+    expect(miniMindMapPreview.doc).toBeDefined();
+    expect(miniMindMapPreview.surface).toBeDefined();
+    expect(miniMindMapPreview.surface!.elementModels.length).toBe(8);
+
+    // renderer
     expect(miniMindMapSurface.renderer).toBeDefined();
     expect(miniMindMapSurface.renderer?.canvas.isConnected).toBe(true);
     expect(miniMindMapSurface.renderer?.canvas.width).toBeGreaterThan(0);
     expect(miniMindMapSurface.renderer?.canvas.height).toBeGreaterThan(0);
 
-    expect(miniMindMapSurface.model.elementModels.length).toBe(8);
-
     return () => {
       miniMindMapPreview.remove();
     };
   });
 
-  test('new mind map should layout automatically', async () => {
-    const gfx = editor.std.get(GfxControllerIdentifier);
-    const mindmapId = gfx.surface!.addElement({
-      type: 'mindmap',
-      children: {
-        text: 'Main node',
-        children: [
-          {
-            text: 'Child node',
-          },
-          {
-            text: 'Second child node',
-          },
-          {
-            text: 'Third child node',
-          },
-        ],
-      },
-    });
-    const mindmap = gfx.getElementById(mindmapId) as MindmapElementModel;
-    await wait(0);
-    const [child1, child2, child3] = mindmap.tree.children;
+  test('mini mindmap should layout automatically', async () => {
+    const mindmapAnswer = `
+  - Main node
+    - Child node
+    - Second child node
+    - Third child node
+  `;
 
-    expect(mindmapId).not.toBeUndefined();
-    expect(mindmap.tree.children.length).toBe(3);
-    expect(mindmap.tree.element.x).toBeLessThan(child1.element.x);
+    const miniMindMapPreview = createPreview(
+      window.editor.host!,
+      mindmapAnswer
+    );
+
+    await wait(50);
+    const gfx = miniMindMapPreview.portalHost.std.get(GfxControllerIdentifier);
+    const mindmap = gfx.surface!.elementModels.filter(
+      model => model.type === 'mindmap'
+    )[0] as MindmapElementModel;
+    const [child1, child2, child3] = mindmap.tree.children;
+    const root = mindmap.tree;
+
+    expect(mindmap).not.toBeUndefined();
+
+    expect(root.children.length).toBe(3);
+    expect(root.element.x).toBeLessThan(child1.element.x);
+
+    // children should be aligned horizontally
     expect(child1.element.x).toBe(child2.element.x);
     expect(child2.element.x).toBe(child3.element.x);
-    expect(child1.element.y).toBeLessThan(child2.element.y);
-    expect(child2.element.y).toBeLessThan(child3.element.y);
+
+    // children
+    expect(child1.element.y + child1.element.h).toBeLessThan(child2.element.y);
+    expect(child2.element.y + child2.element.h).toBeLessThan(child3.element.y);
   });
 });