AuditService (#2)

* Add AuditService.

* Change sha1 to use Webcrypto.

* Add interface for AuditService.

* Move PwnedPasswodsApi constant outside class.

* Change FromBufferToHex implementation to simpler code.

* Use correct string to array function.

* Change auditService interface to abstract class. Add missing type to utils.

src/services/audit.service.ts

@@ -0,0 +1,26 @@
+import { CryptoService } from '../abstractions/crypto.service';
+
+const PwnedPasswordsApi = 'https://api.pwnedpasswords.com/range/';
+
+export class AuditService {
+
+    constructor(private cryptoService: CryptoService) {
+    }
+
+    async passwordLeaked(password: string): Promise<number> {
+        const hash = (await this.cryptoService.sha1(password)).toUpperCase();
+
+        const response = await fetch(PwnedPasswordsApi + hash.substr(0, 5));
+        const leakedHashes = await response.text();
+
+        const hashEnding = hash.substr(5);
+
+        const match = leakedHashes
+            .split(/\r?\n/)
+            .find((v) => {
+                return v.split(':')[0] === hashEnding;
+            });
+
+        return match ? parseInt(match.split(':')[1], 10) : 0;
+    }
+}