created a localised login system

src/services/CredentialEncryption.js

@@ -0,0 +1,96 @@
+/**
+ * Credential Encryption Service
+ *
+ * Encrypts sensitive credentials before storing in database
+ * Uses base64 encoding (React Native compatible)
+ * For production, use a proper encryption library like react-native-aes-crypto
+ */
+
+class CredentialEncryption {
+  constructor() {
+    // Simple key for demo - in production, use proper key management
+    this.encryptionKey = 'photo-app-secret-key-2026';
+  }
+
+  /**
+   * Base64 encode a string (React Native compatible)
+   * Uses btoa which is available in React Native
+   */
+  base64Encode(str) {
+    try {
+      // btoa is available in React Native
+      return btoa(unescape(encodeURIComponent(str)));
+    } catch (error) {
+      console.error('Base64 encode error:', error);
+      throw new Error('Failed to encode data');
+    }
+  }
+
+  /**
+   * Base64 decode a string (React Native compatible)
+   * Uses atob which is available in React Native
+   */
+  base64Decode(str) {
+    try {
+      // atob is available in React Native
+      return decodeURIComponent(escape(atob(str)));
+    } catch (error) {
+      console.error('Base64 decode error:', error);
+      throw new Error('Failed to decode data');
+    }
+  }
+
+  /**
+   * Encrypt credentials before storing
+   * Converts object to JSON string, then base64 encodes it
+   */
+  encrypt(data) {
+    try {
+      if (!data) {
+        throw new Error('No data provided to encrypt');
+      }
+      const jsonString = JSON.stringify(data);
+      const encoded = this.base64Encode(jsonString);
+      console.log('✓ Credentials encrypted successfully');
+      return encoded;
+    } catch (error) {
+      console.error('Encryption error:', error);
+      throw new Error('Failed to encrypt credentials: ' + error.message);
+    }
+  }
+
+  /**
+   * Decrypt credentials after retrieving
+   * Base64 decodes, then parses JSON back to object
+   */
+  decrypt(encryptedData) {
+    try {
+      if (!encryptedData) {
+        return null;
+      }
+      const jsonString = this.base64Decode(encryptedData);
+      const data = JSON.parse(jsonString);
+      console.log('✓ Credentials decrypted successfully');
+      return data;
+    } catch (error) {
+      console.error('Decryption error:', error);
+      throw new Error('Failed to decrypt credentials: ' + error.message);
+    }
+  }
+
+  /**
+   * Check if data is already encrypted (base64)
+   */
+  isEncrypted(data) {
+    if (typeof data !== 'string') return false;
+    try {
+      this.base64Decode(data);
+      return true;
+    } catch {
+      return false;
+    }
+  }
+}
+
+export default new CredentialEncryption();
+