feat: implement signature normalization and storage in contract upload process

controller/documents/ContractUploadController.js

@@ -1,7 +1,27 @@
 const UnitOfWork = require('../../database/UnitOfWork');
 const ContractUploadService = require('../../services/contracts/ContractUploadService');
+const UserDocumentRepository = require('../../repositories/documents/UserDocumentRepository');
 const { logger } = require('../../middleware/logger');
 
+function normalizeSignature(signatureImage) {
+  if (!signatureImage) return null;
+  const str = String(signatureImage);
+  const m = str.match(/^data:(.+);base64,(.+)$/);
+  if (m && m[2]) {
+    const mime = m[1] || 'image/png';
+    const base64 = m[2];
+    const size = Buffer.from(base64, 'base64').length;
+    return { base64, mime, size };
+  }
+  try {
+    const size = Buffer.from(str, 'base64').length;
+    return { base64: str, mime: 'image/png', size };
+  } catch (e) {
+    logger.warn('[ContractUploadController] normalizeSignature failed to parse provided signature');
+    return null;
+  }
+}
+
 class ContractUploadController {
   static async uploadPersonalContract(req, res) {
     const userId = req.user.userId;
@@ -13,6 +33,22 @@ class ContractUploadController {
     const unitOfWork = new UnitOfWork();
     await unitOfWork.start();
     try {
+      const signatureMeta = normalizeSignature(signatureImage);
+      const repo = new UserDocumentRepository(unitOfWork);
+      if (signatureMeta) {
+        await repo.insertDocument({
+          userId,
+          documentType: 'signature',
+          contractType: 'contract',
+          objectStorageId: null,
+          signatureBase64: signatureMeta.base64,
+          originalFilename: 'signature.png',
+          fileSize: signatureMeta.size,
+          mimeType: signatureMeta.mime
+        });
+        logger.info('[ContractUploadController] signature stored for user', { userId, bytes: signatureMeta.size });
+      }
+
       const uploads = [];
       // Primary contract
       uploads.push(await ContractUploadService.uploadContract({
@@ -22,7 +58,7 @@ class ContractUploadController {
         contractCategory: 'personal',
         unitOfWork,
         contractData,
-        signatureImage,
+        signatureImage: signatureMeta ? signatureMeta.base64 : null,
         contract_type: 'contract',
         user_type: 'personal'
       }));
@@ -34,11 +70,17 @@ class ContractUploadController {
         contractCategory: 'personal',
         unitOfWork,
         contractData,
-        signatureImage,
+        signatureImage: signatureMeta ? signatureMeta.base64 : null,
         contract_type: 'gdpr',
         user_type: 'personal'
       }));
 
+      // Cleanup standalone signature record after contracts are saved
+      if (signatureMeta) {
+        await repo.deleteSignatureDocumentsForUser(userId);
+        logger.info('[ContractUploadController] signature cleanup completed for user', { userId });
+      }
+
       await unitOfWork.commit();
       logger.info(`[ContractUploadController] uploadPersonalContract success for userId: ${userId}`);
       res.json({ success: true, uploads, downloadUrls: uploads.map(u => u.url || null) });
@@ -58,6 +100,22 @@ class ContractUploadController {
     const unitOfWork = new UnitOfWork();
     await unitOfWork.start();
     try {
+      const signatureMeta = normalizeSignature(signatureImage);
+      const repo = new UserDocumentRepository(unitOfWork);
+      if (signatureMeta) {
+        await repo.insertDocument({
+          userId,
+          documentType: 'signature',
+          contractType: 'contract',
+          objectStorageId: null,
+          signatureBase64: signatureMeta.base64,
+          originalFilename: 'signature.png',
+          fileSize: signatureMeta.size,
+          mimeType: signatureMeta.mime
+        });
+        logger.info('[ContractUploadController] signature stored for company user', { userId, bytes: signatureMeta.size });
+      }
+
       const result = await ContractUploadService.uploadContract({
         userId,
         file,
@@ -65,11 +123,15 @@ class ContractUploadController {
         contractCategory: 'company',
         unitOfWork,
         contractData,
-        signatureImage,
+        signatureImage: signatureMeta ? signatureMeta.base64 : null,
         contract_type: 'contract',
         user_type: 'company'
       });
       await unitOfWork.commit();
+      if (signatureMeta) {
+        await repo.deleteSignatureDocumentsForUser(userId);
+        logger.info('[ContractUploadController] signature cleanup completed for company user', { userId });
+      }
       logger.info(`[ContractUploadController] uploadCompanyContract success for userId: ${userId}`);
       res.json({ success: true, upload: result, downloadUrl: result.url || null });
     } catch (error) {