Need to fill existing form? → pdf-lib
Need complex layouts? → Puppeteer (HTML/CSS)
Need academic formatting? → LaTeX
Need to merge PDFs? → pdf-lib
Need digital signatures? → pdf-lib + DocuSign API

// ❌ Puppeteer for simple form filling (SLOW!)
import puppeteer from 'puppeteer';

async function fillForm(data: FormData): Promise<Buffer> {
  const browser = await puppeteer.launch();
  const page = await browser.newPage();

  // Load PDF in browser
  await page.goto(`file://${pdfPath}`);

  // Somehow fill form fields? (hacky)
  await page.evaluate((data) => {
    // Can't easily access PDF form fields from DOM
    // Would need to convert PDF → HTML first
  }, data);

  const pdf = await page.pdf();
  await browser.close();

  return pdf;
}

// ✅ pdf-lib for form filling (FAST!)
import { PDFDocument } from 'pdf-lib';

async function fillForm(templatePath: string, data: FormData): Promise<Uint8Array> {
  // Load existing PDF form
  const existingPdfBytes = await fs.readFile(templatePath);
  const pdfDoc = await PDFDocument.load(existingPdfBytes);

  // Get form
  const form = pdfDoc.getForm();

  // Fill text fields
  form.getTextField('applicant_name').setText(data.name);
  form.getTextField('case_number').setText(data.caseNumber);
  form.getTextField('date_of_birth').setText(data.dob);

  // Fill checkboxes
  if (data.hasPriorConvictions) {
    form.getCheckBox('prior_convictions').check();
  }

  // Fill dropdowns
  form.getDropdown('state').select(data.state);

  // Flatten form (make non-editable)
  form.flatten();

  // Save
  return await pdfDoc.save();
}

// ❌ Don't flatten - form stays editable
const pdfDoc = await PDFDocument.load(existingPdfBytes);
const form = pdfDoc.getForm();

form.getTextField('name').setText('John Doe');

const pdfBytes = await pdfDoc.save();
// User can open PDF and change "John Doe" to anything!

// ✅ Flatten form after filling
const pdfDoc = await PDFDocument.load(existingPdfBytes);
const form = pdfDoc.getForm();

form.getTextField('name').setText('John Doe');

// Flatten (convert fields to static text)
form.flatten();

const pdfBytes = await pdfDoc.save();
// User can't edit filled values ✅

// ❌ No page break control
const html = `
  <div class="contract">
    <h1>Mutual Agreement</h1>
    <p>Long paragraph that might split across pages...</p>
    <section>
      <h2>Terms and Conditions</h2>
      <ol>
        <li>Term 1 that could get cut off...</li>
        <li>Term 2...</li>
      </ol>
    </section>
  </div>
`;

const pdf = await page.pdf({ format: 'A4' });
// Result: Ugly page breaks in middle of sections

// ✅ Explicit page break control with CSS
const html = `
  <style>
    @media print {
      .page-break { page-break-after: always; }
      .avoid-break { page-break-inside: avoid; }

      h1, h2, h3 {
        page-break-after: avoid;
        page-break-inside: avoid;
      }

      section {
        page-break-inside: avoid;
      }
    }
  </style>

  <div class="contract">
    <section class="avoid-break">
      <h1>Mutual Agreement</h1>
      <p>This entire section stays together...</p>
    </section>

    <div class="page-break"></div>

    <section class="avoid-break">
      <h2>Terms and Conditions</h2>
      <ol>
        <li>Term 1</li>
        <li>Term 2</li>
      </ol>
    </section>
  </div>
`;

const pdf = await page.pdf({
  format: 'A4',
  printBackground: true,
  margin: {
    top: '1in',
    right: '1in',
    bottom: '1in',
    left: '1in'
  }
});

// ❌ Add signature as image (not a real signature field)
const pdfDoc = await PDFDocument.load(existingPdfBytes);

const signatureImage = await pdfDoc.embedPng(signaturePngBytes);
const page = pdfDoc.getPage(0);

page.drawImage(signatureImage, {
  x: 100,
  y: 100,
  width: 200,
  height: 50
});

await pdfDoc.save();
// Not a real signature field - can't be signed digitally

// ✅ Create signature field for electronic signing
const pdfDoc = await PDFDocument.load(existingPdfBytes);
const form = pdfDoc.getForm();

// Create signature field
const signatureField = form.createTextField('applicant_signature');
signatureField.addToPage(pdfDoc.getPage(0), {
  x: 100,
  y: 100,
  width: 200,
  height: 50
});

// Mark as signature field (metadata)
signatureField.updateWidgets({
  borderWidth: 1,
  borderColor: { type: 'RGB', red: 0, green: 0, blue: 0 }
});

await pdfDoc.save();
// DocuSign can now detect and fill this field ✅

// ✅ Send to DocuSign for e-signature
import { ApiClient, EnvelopesApi } from 'docusign-esign';

async function sendForSignature(pdfBytes: Uint8Array, signerEmail: string) {
  const apiClient = new ApiClient();
  apiClient.setBasePath('https://demo.docusign.net/restapi');

  const envelopesApi = new EnvelopesApi(apiClient);

  const envelope = {
    emailSubject: 'Please sign: Expungement Petition',
    documents: [{
      documentBase64: Buffer.from(pdfBytes).toString('base64'),
      name: 'Petition.pdf',
      fileExtension: 'pdf',
      documentId: '1'
    }],
    recipients: {
      signers: [{
        email: signerEmail,
        name: 'John Doe',
        recipientId: '1',
        tabs: {
          signHereTabs: [{
            documentId: '1',
            pageNumber: '1',
            xPosition: '100',
            yPosition: '100'
          }]
        }
      }]
    },
    status: 'sent'
  };

  return await envelopesApi.createEnvelope(accountId, { envelopeDefinition: envelope });
}

// ❌ Save PDF to disk unencrypted
const pdfBytes = await pdfDoc.save();
await fs.writeFile(`./documents/${caseId}.pdf`, pdfBytes);
// Sensitive data accessible to anyone with file system access

// ✅ Encrypt PDF with user password
const pdfBytes = await pdfDoc.save({
  userPassword: generateSecurePassword(),
  ownerPassword: process.env.PDF_OWNER_PASSWORD,
  permissions: {
    printing: 'highResolution',
    modifying: false,
    copying: false,
    annotating: false,
    fillingForms: false,
    contentAccessibility: true,
    documentAssembly: false
  }
});

await fs.writeFile(`./documents/${caseId}.pdf`, pdfBytes);

// ✅ Upload to S3 with server-side encryption
import { S3Client, PutObjectCommand } from '@aws-sdk/client-s3';

const s3Client = new S3Client({ region: 'us-east-1' });

await s3Client.send(new PutObjectCommand({
  Bucket: 'expungement-documents',
  Key: `cases/${caseId}/petition.pdf`,
  Body: pdfBytes,
  ServerSideEncryption: 'AES256',
  Metadata: {
    caseId: caseId,
    documentType: 'petition',
    generatedAt: new Date().toISOString()
  },
  ACL: 'private'  // Not publicly accessible
}));

// Store S3 URL in database (encrypted)
await db.documents.insert({
  case_id: caseId,
  s3_url: encrypt(`s3://expungement-documents/cases/${caseId}/petition.pdf`),
  created_at: new Date()
});

□ Form fields filled correctly (test with validation)
□ Forms flattened after filling (non-editable)
□ Page breaks controlled (no mid-sentence splits)
□ Signature fields created (for DocuSign/Adobe Sign)
□ PDFs encrypted at rest (S3 SSE or user password)
□ Access logged (who viewed/downloaded)
□ Auto-deletion scheduled (retention policy)
□ Fonts embedded (cross-platform compatibility)
□ File size optimized (<5MB per document)
□ Batch generation tested (1000+ PDFs)

1. FILLABLE PDF → Use form.getTextField().setText() (best)
2. FLAT PDF + COORDINATES → Draw text overlays at X,Y positions (this section)
3. NO TEMPLATE EXISTS → Emergency fallback with warning banner (worst)

// ❌ NEVER DO THIS - courts reject custom forms
const pdfDoc = await PDFDocument.create();
const page = pdfDoc.addPage([612, 792]);

page.drawText('IN THE CIRCUIT COURT OF...', { x: 200, y: 720 });
page.drawText(`Defendant: ${data.name}`, { x: 100, y: 600 });
// Result: Court clerk says "This isn't our form" and rejects filing

// ✅ Load official form, draw text in blank spaces
const templateBytes = await fs.readFile('public/forms/OR-set-aside-motion.pdf');
const pdfDoc = await PDFDocument.load(templateBytes);
const page = pdfDoc.getPage(3); // Page 4 is the form
const font = await pdfDoc.embedFont(StandardFonts.Helvetica);

// Draw in blank spaces at measured coordinates
page.drawText(data.county.toUpperCase(), { x: 310, y: 700, size: 11, font });
page.drawText(data.caseNumber, { x: 432, y: 655, size: 10, font });
page.drawText(data.fullName, { x: 72, y: 568, size: 11, font });

// field-mappings/oregon-set-aside.json
{
  "templatePath": "/forms/or/OR-criminal-set-aside.pdf",
  "pageIndex": 3,
  "fields": [
    {
      "name": "county",
      "x": 310,
      "y": 700,
      "fontSize": 11,
      "maxWidth": 120,
      "transform": "uppercase"
    },
    {
      "name": "caseNumber",
      "x": 432,
      "y": 655,
      "fontSize": 10,
      "maxWidth": 100,
      "maxChars": 12
    },
    {
      "name": "fullName",
      "x": 72,
      "y": 568,
      "fontSize": 11,
      "maxWidth": 250,
      "shrinkToFit": true
    }
  ]
}

async function drawDebugGrid(page: PDFPage, font: PDFFont) {
  const { width, height } = page.getSize();

  // Draw grid every 50 points
  for (let x = 0; x <= width; x += 50) {
    page.drawLine({
      start: { x, y: 0 },
      end: { x, y: height },
      thickness: 0.2,
      color: rgb(0.9, 0.9, 0.9),
    });
    if (x % 100 === 0) {
      page.drawText(String(x), { x: x + 2, y: 5, size: 6, font });
    }
  }
  // Same for horizontal lines...
}

// 1. Truncate with ellipsis
function truncate(text: string, maxChars: number): string {
  if (text.length <= maxChars) return text;
  return text.slice(0, maxChars - 2) + '..';
}

// 2. Shrink font to fit (min 7pt for readability)
function shrinkToFit(text: string, maxWidthPts: number, startSize: number): number {
  let fontSize = startSize;
  const charWidth = (size: number) => size * 0.52; // Helvetica avg

  while (fontSize > 7 && text.length * charWidth(fontSize) > maxWidthPts) {
    fontSize -= 0.5;
  }
  return fontSize;
}

// 3. Multi-line wrap (for addresses)
page.drawText(longAddress, {
  x: 100,
  y: 500,
  size: 9,
  font,
  maxWidth: 200, // pdf-lib auto-wraps at this width
  lineHeight: 12,
});

export const FIELD_CONSTRAINTS = {
  fullName: { maxLength: 35 },
  county: { maxLength: 12 },
  caseNumber: { maxLength: 12 },
  agency: { maxLength: 28 },
  charges: { maxLength: 45 },
} as const;

1. DOWNLOAD official forms
   └─ Store in /public/forms/{state}/ with metadata.json

2. INSPECT each form
   └─ Run pdf-lib inspection to check: fillable? how many fields?

3. CATEGORIZE forms
   ├─ Fillable → Map field names in field-mappings/{state}.ts
   └─ Flat → Measure coordinates with pdf-coordinates tool

4. CREATE JSON config for flat PDFs
   └─ One JSON file per form with all X,Y coordinates

5. TEST with debug grid
   └─ Generate test PDF with colored text + coordinate labels

6. QA visual verification
   └─ Compare filled PDF against original blank form

7. DOCUMENT constraints
   └─ Export maxLength/maxWidth limits for form inputs

// If form had fields, flatten them
const form = pdfDoc.getForm();
if (form.getFields().length > 0) {
  form.flatten(); // Converts to static text
}

// For overlay text, it's already static - no flattening needed
const pdfBytes = await pdfDoc.save();

PDF coordinate system (pdf-lib default):
- Origin: Bottom-left corner (0, 0)
- X increases: Left → Right
- Y increases: Bottom → Top
- Units: Points (72 points = 1 inch)
- Letter size: 612 x 792 points (8.5" x 11")

To convert from top-left origin (e.g., Adobe Acrobat display):
  y_pdf = 792 - y_topLeft

Common positions (Letter size):
- Top margin: y = 720-750
- Header area: y = 700-750
- Body start: y = 650-700
- Left margin: x = 50-72
- Right edge: x = 540-560
- Bottom margin: y = 50-72