[매입] mg_recv_svc → 전문수신 @Service (ACM-MG-004)

boot/modules/acquiring/src/main/java/com/klaro/acquirecore/acquiring/codec/MessageCodec.java

@@ -0,0 +1,91 @@
+package com.klaro.acquirecore.acquiring.codec;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.stereotype.Component;
+
+/**
+ * 전문 인코딩/디코딩 컴포넌트
+ * Fixed-length 필드 기반 전문 파싱
+ */
+@Component
+public class MessageCodec {
+
+    private static final Logger log = LoggerFactory.getLogger(MessageCodec.class);
+
+    private static final int LEN_TX_TYPE = 4;
+    private static final int LEN_TRACE_NO = 12;
+    private static final int LEN_MERCHANT_ID = 15;
+    private static final int LEN_AMOUNT = 12;
+    private static final int LEN_CARD_NO = 20;
+    private static final int LEN_EXPIRY = 4;
+    private static final int LEN_INSTALLMENTS = 2;
+    private static final int LEN_FILLER = 99;
+
+    public UnpackedMessage unpack(byte[] rawMessage) {
+        if (rawMessage == null || rawMessage.length == 0) {
+            throw new IllegalArgumentException("Empty message");
+        }
+
+        String data = new String(rawMessage);
+        int offset = 0;
+
+        UnpackedMessage unpacked = new UnpackedMessage();
+        unpacked.setRawData(data);
+
+        unpacked.setTxType(extract(data, offset, LEN_TX_TYPE));
+        offset += LEN_TX_TYPE;
+
+        unpacked.setTraceNo(extract(data, offset, LEN_TRACE_NO));
+        offset += LEN_TRACE_NO;
+
+        unpacked.setMerchantId(extract(data, offset, LEN_MERCHANT_ID));
+        offset += LEN_MERCHANT_ID;
+
+        unpacked.setAmount(extract(data, offset, LEN_AMOUNT));
+        offset += LEN_AMOUNT;
+
+        unpacked.setCardNo(extract(data, offset, LEN_CARD_NO));
+        offset += LEN_CARD_NO;
+
+        unpacked.setExpiryDate(extract(data, offset, LEN_EXPIRY));
+        offset += LEN_EXPIRY;
+
+        unpacked.setInstallments(extract(data, offset, LEN_INSTALLMENTS));
+        offset += LEN_INSTALLMENTS;
+
+        if (data.length() > offset) {
+            unpacked.setFiller(extract(data, offset, Math.min(LEN_FILLER, data.length() - offset)));
+        }
+
+        log.debug("Message unpacked: txType={}, traceNo={}", unpacked.getTxType(), unpacked.getTraceNo());
+        return unpacked;
+    }
+
+    public byte[] pack(UnpackedMessage unpacked) {
+        StringBuilder sb = new StringBuilder();
+        sb.append(padRight(unpacked.getTxType(), LEN_TX_TYPE));
+        sb.append(padRight(unpacked.getTraceNo(), LEN_TRACE_NO));
+        sb.append(padRight(unpacked.getMerchantId(), LEN_MERCHANT_ID));
+        sb.append(padRight(unpacked.getAmount(), LEN_AMOUNT));
+        sb.append(padRight(unpacked.getCardNo(), LEN_CARD_NO));
+        sb.append(padRight(unpacked.getExpiryDate(), LEN_EXPIRY));
+        sb.append(padRight(unpacked.getInstallments(), LEN_INSTALLMENTS));
+        sb.append(padRight(unpacked.getFiller(), LEN_FILLER));
+        return sb.toString().getBytes();
+    }
+
+    private String extract(String data, int offset, int length) {
+        if (offset >= data.length()) return "";
+        int end = Math.min(offset + length, data.length());
+        return data.substring(offset, end).trim();
+    }
+
+    private String padRight(String value, int length) {
+        if (value == null) value = "";
+        if (value.length() >= length) return value.substring(0, length);
+        StringBuilder sb = new StringBuilder(value);
+        while (sb.length() < length) sb.append(' ');
+        return sb.toString();
+    }
+}