working web based and intent

src/main/java/com/billpaymentservice/bbps/util/BillerMapperHelper.java

@@ -1081,18 +1081,25 @@ public class BillerMapperHelper {
 	}
 
 	public void savePaymentStartRecord(PaymentStartUserRequest request, PaymentStartApiResponse apiResponse,
-			String txnId, String orderNo) {
+			String txnId, String orderNo, String requestJson, String rawResponse, String responseType) {
 		PaymentStartRecord record = new PaymentStartRecord();
 		record.setOrderNo(orderNo);
 		record.setRequestId(request.getReqId());
 		record.setClientMid(request.getMid());
 		record.setClientUserId(request.getClientUserId());
 		record.setInternalTxnId(txnId);
-		record.setAmount(apiResponse.getResponseData().getAmount());
-		record.setMid(apiResponse.getResponseData().getMid());
-		record.setTxnId(apiResponse.getResponseData().getTxnId());
-		record.setQrString(apiResponse.getResponseData().getQrString());
-		record.setCreatedOn(apiResponse.getResponseData().getCreatedOn());
+		if (apiResponse != null && apiResponse.getResponseData() != null) {
+			record.setAmount(apiResponse.getResponseData().getAmount());
+			record.setMid(apiResponse.getResponseData().getMid());
+			record.setTxnId(apiResponse.getResponseData().getTxnId());
+			record.setQrString(apiResponse.getResponseData().getQrString());
+			record.setCreatedOn(apiResponse.getResponseData().getCreatedOn());
+		}
+
+		// store the original request body and raw response
+		record.setRequestBody(requestJson);
+		record.setResponseBody(rawResponse);
+		record.setResponseType(responseType);
 
 		paymentStartRecordRepository.save(record);
 	}

src/main/java/com/billpaymentservice/bbps/util/EncryptionUtil.java

@@ -1,7 +1,11 @@
 package com.billpaymentservice.bbps.util;
 
+import java.io.ByteArrayInputStream;
+import java.io.IOException;
+import java.io.InputStream;
 import java.nio.charset.StandardCharsets;
 import java.util.Base64;
+import java.util.zip.CRC32;
 
 import javax.crypto.Cipher;
 import javax.crypto.spec.IvParameterSpec;
@@ -18,12 +22,9 @@ public class EncryptionUtil {
     /**
      * Encrypts plaintext using AES/CBC/PKCS5Padding.
      * If the provided key length is not 16/24/32 bytes it will be adjusted to 16 bytes (padded/truncated).
-     * NOTE: This follows the algorithm snippet provided by the user but pads/truncates the key to avoid
-     * common runtime errors when key lengths are incorrect.
      */
     public String encryptMData(String plaintext, String encryptKey) {
         try {
-            // Ensure key length is 16 bytes (AES-128). If callers provide a longer key this will truncate.
             byte[] keyBytes = normalizeKey(encryptKey);
             SecretKeySpec secretKeySpec = new SecretKeySpec(keyBytes, "AES");
             Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
@@ -61,4 +62,56 @@ public class EncryptionUtil {
         }
         return normalized;
     }
-}
+
+    /**
+     * Decrypts data encrypted by encryptMData: Base64(iv + ciphertext) with AES/CBC/PKCS5Padding
+     */
+    public String decryptMData(String base64Payload, String encryptKey) {
+        if (base64Payload == null) return null;
+        try {
+            byte[] combined = Base64.getDecoder().decode(base64Payload);
+            // IV is first 16 bytes for AES
+            if (combined.length < 16) {
+                LOGGER.warn("Encrypted payload too short to contain IV");
+                return null;
+            }
+            byte[] iv = new byte[16];
+            System.arraycopy(combined, 0, iv, 0, 16);
+            byte[] cipherText = new byte[combined.length - 16];
+            System.arraycopy(combined, 16, cipherText, 0, cipherText.length);
+
+            byte[] keyBytes = normalizeKey(encryptKey);
+            SecretKeySpec secretKeySpec = new SecretKeySpec(keyBytes, "AES");
+
+            Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
+            cipher.init(Cipher.DECRYPT_MODE, secretKeySpec, new IvParameterSpec(iv));
+
+            byte[] plain = cipher.doFinal(cipherText);
+            return new String(plain, StandardCharsets.UTF_8);
+        } catch (Exception ex) {
+            LOGGER.error("Error decrypting payload: {}", ex.getMessage());
+            return null;
+        }
+    }
+
+    /**
+     * Compute CRC32 checksum value for the provided input string and return the numeric value as String
+     */
+    public String getChecksumCRC32(String input) {
+        if (input == null) input = "";
+        try (InputStream is = new ByteArrayInputStream(input.getBytes(StandardCharsets.UTF_8))) {
+            CRC32 crc = new CRC32();
+            byte[] buffer = new byte[1024];
+            int len;
+            while ((len = is.read(buffer)) != -1) {
+                crc.update(buffer, 0, len);
+            }
+            long value = crc.getValue();
+            LOGGER.debug("Computed CRC32: {} for input: {}", value, input);
+            return String.valueOf(value);
+        } catch (IOException e) {
+            LOGGER.error("Error computing CRC32: {}", e.getMessage());
+            return null;
+        }
+    }
+}