first commit

src/services/BlockchainService.ts

@@ -0,0 +1,73 @@
+import OpenTimestamps from 'opentimestamps-javascript'; // Atualizar import
+import { createHash } from 'crypto';
+import * as fs from 'fs/promises';
+import * as path from 'path';
+
+export class BlockchainService {
+  private readonly storageDir: string;
+
+  constructor() {
+    this.storageDir = path.join(process.cwd(), 'storage', 'timestamps');
+    this.ensureStorageDir();
+  }
+
+  private async ensureStorageDir() {
+    try {
+      await fs.mkdir(this.storageDir, { recursive: true });
+    } catch (error) {
+      console.error('Erro ao criar diretório de timestamps:', error);
+    }
+  }
+
+  async createTimestamp(buffer: Buffer) {
+    try {
+      // 1. Criar hash do arquivo
+      const fileHash = createHash('sha256').update(buffer).digest();
+
+      // 2. Criar timestamp
+      const timestamp = await OpenTimestamps.stamp(fileHash);
+
+      // 3. Salvar arquivo .ots
+      const otsPath = path.join(this.storageDir, `${fileHash.toString('hex')}.ots`);
+      await fs.writeFile(otsPath, Buffer.from(timestamp));
+
+      return {
+        hash: fileHash.toString('hex'),
+        timestamp,
+        otsPath
+      };
+    } catch (error) {
+      console.error('Erro ao criar timestamp:', error);
+      throw new Error('Falha ao criar timestamp na blockchain');
+    }
+  }
+
+  async verifyTimestamp(hash: string, timestamp: Buffer) {
+    try {
+      // Usar a API correta do OpenTimestamps
+      const result = await OpenTimestamps.verify(
+        Buffer.from(timestamp),
+        Buffer.from(hash, 'hex')
+      );
+      
+      if (!result) {
+        return { 
+          verified: false, 
+          message: 'Timestamp ainda não confirmado na blockchain' 
+        };
+      }
+
+      return {
+        verified: true,
+        timestamp: new Date(result * 1000),
+        message: 'Timestamp verificado na blockchain do Bitcoin'
+      };
+    } catch (error) {
+      console.error('Erro ao verificar timestamp:', error);
+      return { 
+        verified: false, 
+        message: 'Erro ao verificar timestamp' 
+      };
+    }
+  }
+}