feat: add document OCR and offline model archives

src/main/document-parsing-service.test.ts

@@ -0,0 +1,130 @@
+import { describe, expect, it, vi } from 'vitest'
+import {
+  defaultDocumentParsingSettings
+} from './document-parsing-settings-store'
+import { DocumentParsingService } from './document-parsing-service'
+
+function createPdfFixture(text: string): Buffer {
+  const stream = `BT /F1 18 Tf 50 100 Td (${text}) Tj ET`
+  const objects = [
+    '<< /Type /Catalog /Pages 2 0 R >>',
+    '<< /Type /Pages /Kids [3 0 R] /Count 1 >>',
+    '<< /Type /Page /Parent 2 0 R /MediaBox [0 0 300 200] /Resources << /Font << /F1 4 0 R >> >> /Contents 5 0 R >>',
+    '<< /Type /Font /Subtype /Type1 /BaseFont /Helvetica >>',
+    `<< /Length ${Buffer.byteLength(stream)} >>\nstream\n${stream}\nendstream`
+  ]
+  let content = '%PDF-1.4\n'
+  const offsets = [0]
+  for (const [index, object] of objects.entries()) {
+    offsets.push(Buffer.byteLength(content))
+    content += `${index + 1} 0 obj\n${object}\nendobj\n`
+  }
+  const xrefOffset = Buffer.byteLength(content)
+  content += `xref\n0 ${objects.length + 1}\n`
+  content += '0000000000 65535 f \n'
+  content += offsets
+    .slice(1)
+    .map((offset) => `${String(offset).padStart(10, '0')} 00000 n \n`)
+    .join('')
+  content += `trailer\n<< /Size ${objects.length + 1} /Root 1 0 R >>\n`
+  content += `startxref\n${xrefOffset}\n%%EOF\n`
+  return Buffer.from(content)
+}
+
+function createService(overrides?: {
+  settings?: Partial<typeof defaultDocumentParsingSettings>
+}) {
+  const settings = {
+    ...defaultDocumentParsingSettings,
+    ...overrides?.settings
+  }
+  const recognize = vi.fn(async () => ({
+    requestId: crypto.randomUUID(),
+    sections: [
+      {
+        locator: '第 1 页',
+        content: '扫描件识别正文',
+        confidence: 0.93
+      }
+    ],
+    pageCount: 1,
+    warnings: []
+  }))
+  const service = new DocumentParsingService(
+    {
+      get: vi.fn(async () => settings),
+      update: vi.fn(async () => settings)
+    } as never,
+    {
+      getStatus: vi.fn(async () => ({
+        id: 'pp-ocrv6-tiny',
+        displayName: 'PP-OCRv6 Tiny',
+        available: true,
+        verified: true,
+        runtime: 'onnxruntime-web-wasm',
+        detail: '可用'
+      }))
+    } as never,
+    { recognize } as never
+  )
+  return { recognize, service }
+}
+
+describe('DocumentParsingService', () => {
+  it('keeps useful PDF text local without invoking OCR', async () => {
+    const { recognize, service } = createService()
+
+    const parsed = await service.parse(
+      'native.pdf',
+      createPdfFixture('Native PDF body text'),
+      'knowledge-index'
+    )
+
+    expect(parsed.content).toContain('Native PDF body text')
+    expect(parsed.sections[0]?.method).toBe('native')
+    expect(recognize).not.toHaveBeenCalled()
+  })
+
+  it('uses OCR for a PDF without useful text', async () => {
+    const { recognize, service } = createService()
+
+    const parsed = await service.parse(
+      'scan.pdf',
+      createPdfFixture(''),
+      'chat-attachment'
+    )
+
+    expect(parsed.content).toBe('扫描件识别正文')
+    expect(parsed.sections).toEqual([
+      {
+        locator: '第 1 页',
+        content: '扫描件识别正文',
+        method: 'ocr',
+        confidence: 0.93
+      }
+    ])
+    expect(recognize).toHaveBeenCalledWith(
+      expect.objectContaining({
+        fileName: 'scan.pdf',
+        modelId: 'pp-ocrv6-tiny',
+        mimeType: 'application/pdf',
+        pageNumbers: [1]
+      })
+    )
+  })
+
+  it('does not use OCR in a fast-text workflow', async () => {
+    const { recognize, service } = createService({
+      settings: { chatWorkflow: 'fast-text' }
+    })
+
+    await expect(
+      service.parse(
+        'scan.pdf',
+        createPdfFixture(''),
+        'chat-attachment'
+      )
+    ).rejects.toThrow('未启用 OCR')
+    expect(recognize).not.toHaveBeenCalled()
+  })
+})