feat: add notes preview helper with tests

Made-with: Cursor

tests/api/session-notes.test.js

@@ -0,0 +1,64 @@
+const { computeNotesPreview } = require('../../backend/utils/notes-preview');
+
+describe('computeNotesPreview', () => {
+  test('returns has_notes false and null preview for null input', () => {
+    const result = computeNotesPreview(null);
+    expect(result).toEqual({ has_notes: false, notes_preview: null });
+  });
+
+  test('returns has_notes false and null preview for empty string', () => {
+    const result = computeNotesPreview('');
+    expect(result).toEqual({ has_notes: false, notes_preview: null });
+  });
+
+  test('returns first paragraph as preview', () => {
+    const notes = 'First paragraph here.\n\nSecond paragraph here.';
+    const result = computeNotesPreview(notes);
+    expect(result.has_notes).toBe(true);
+    expect(result.notes_preview).toBe('First paragraph here.');
+  });
+
+  test('strips markdown bold formatting', () => {
+    const notes = '**Bold text** and more';
+    const result = computeNotesPreview(notes);
+    expect(result.notes_preview).toBe('Bold text and more');
+  });
+
+  test('strips markdown italic formatting', () => {
+    const notes = '*Italic text* and _also italic_';
+    const result = computeNotesPreview(notes);
+    expect(result.notes_preview).toBe('Italic text and also italic');
+  });
+
+  test('strips markdown links', () => {
+    const notes = 'Check [this link](http://example.com) out';
+    const result = computeNotesPreview(notes);
+    expect(result.notes_preview).toBe('Check this link out');
+  });
+
+  test('strips markdown headers', () => {
+    const notes = '## Header text';
+    const result = computeNotesPreview(notes);
+    expect(result.notes_preview).toBe('Header text');
+  });
+
+  test('strips markdown list markers', () => {
+    const notes = '- Item one\n- Item two';
+    const result = computeNotesPreview(notes);
+    expect(result.notes_preview).toBe('Item one Item two');
+  });
+
+  test('truncates to 150 characters with ellipsis', () => {
+    const notes = 'A'.repeat(200);
+    const result = computeNotesPreview(notes);
+    expect(result.notes_preview).toHaveLength(153); // 150 + '...'
+    expect(result.notes_preview.endsWith('...')).toBe(true);
+  });
+
+  test('does not truncate text at or under 150 characters', () => {
+    const notes = 'A'.repeat(150);
+    const result = computeNotesPreview(notes);
+    expect(result.notes_preview).toHaveLength(150);
+    expect(result.notes_preview).not.toContain('...');
+  });
+});