boot/modules/acquiring/src/main/java/com/klaro/acquirecore/acquiring/service/TxMessageCodec.java

@@ -0,0 +1,158 @@
+package com.klaro.acquirecore.acquiring.service;
+
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import com.klaro.acquirecore.acquiring.dto.TxMessage;
+import org.springframework.stereotype.Component;
+
+import java.nio.ByteBuffer;
+import java.nio.charset.StandardCharsets;
+import java.time.LocalDateTime;
+import java.time.format.DateTimeFormatter;
+import java.util.UUID;
+
+/**
+ * Codec for TX message packing/unpacking.
+ * Handles binary protocol ↔ domain object conversion.
+ */
+@Component
+public class TxMessageCodec {
+
+    private static final DateTimeFormatter DT_FORMAT = DateTimeFormatter.ofPattern("yyyyMMddHHmmss");
+    private static final String ENCODING = "EUC-KR";
+
+    private final ObjectMapper objectMapper;
+
+    public TxMessageCodec(ObjectMapper objectMapper) {
+        this.objectMapper = objectMapper;
+    }
+
+    /**
+     * Unpack binary message to TxMessage domain object.
+     * Format: HEADER(20) + BODY(n)
+     */
+    public TxMessage unpack(byte[] raw) {
+        if (raw == null || raw.length < 20) {
+            throw new IllegalArgumentException("Invalid message: too short");
+        }
+        ByteBuffer buf = ByteBuffer.wrap(raw);
+
+        // HEADER: 20 bytes
+        byte[] headerBytes = new byte[20];
+        buf.get(headerBytes);
+        String header = new String(headerBytes, StandardCharsets.ISO_8859_1).trim();
+
+        // BODY: remaining bytes
+        byte[] bodyBytes = new byte[raw.length - 20];
+        buf.get(bodyBytes);
+
+        TxMessage msg = new TxMessage();
+        msg.setHeader(header);
+        msg.setRawBody(bodyBytes);
+
+        // Parse body as JSON or delimited fields
+        parseBody(msg, bodyBytes);
+
+        return msg;
+    }
+
+    private void parseBody(TxMessage msg, byte[] body) {
+        String bodyStr = new String(body, StandardCharsets.ISO_8859_1);
+        try {
+            JsonNode node = objectMapper.readTree(bodyStr);
+            if (node.isObject()) {
+                ObjectNode obj = (ObjectNode) node;
+                obj.fields().forEachRemaining(e -> {
+                    String key = e.getKey();
+                    JsonNode val = e.getValue();
+                    if (val.isTextual()) {
+                        setField(msg, key, val.asText());
+                    } else if (val.isNumber()) {
+                        setNumericField(msg, key, val.asLong());
+                    }
+                });
+            }
+        } catch (Exception e) {
+            // Fallback: delimited parse
+            parseDelimited(msg, bodyStr);
+        }
+    }
+
+    private void parseDelimited(TxMessage msg, String body) {
+        String[] fields = body.split("\\|");
+        for (int i = 0; i < fields.length; i++) {
+            String[] kv = fields[i].split("=", 2);
+            if (kv.length == 2) {
+                setField(msg, kv[0].trim(), kv[1].trim());
+            }
+        }
+    }
+
+    private void setField(TxMessage msg, String key, String value) {
+        switch (key.toUpperCase()) {
+            case "TXID": msg.setTxId(value); break;
+            case "MERCHANTID": msg.setMerchantId(value); break;
+            case "TERMINALID": msg.setTerminalId(value); break;
+            case "AMOUNT": msg.setAmount(value); break;
+            case "STATUS": msg.setStatus(value); break;
+            case "TRANDATE": msg.setTranDate(value); break;
+            case "TRANTIME": msg.setTranTime(value); break;
+            case "AUTHNO": msg.setAuthNo(value); break;
+            case "CARDNO": msg.setCardNo(value); break;
+            case "VANMSG": msg.setVanMsg(value); break;
+            default: msg.setExtra(key, value);
+        }
+    }
+
+    private void setNumericField(TxMessage msg, String key, long value) {
+        if ("AMOUNT".equalsIgnoreCase(key)) {
+            msg.setAmount(String.valueOf(value));
+        }
+    }
+
+    /**
+     * Pack TxMessage to binary format.
+     */
+    public byte[] pack(TxMessage msg) {
+        byte[] body = packBody(msg);
+        byte[] header = buildHeader(msg, body.length);
+
+        ByteBuffer buf = ByteBuffer.allocate(header.length + body.length);
+        buf.put(header);
+        buf.put(body);
+        return buf.array();
+    }
+
+    private byte[] buildHeader(TxMessage msg, int bodyLen) {
+        String header = String.format("%-20s",
+            msg.getTxId() != null ? msg.getTxId() : UUID.randomUUID().toString().substring(0, 8));
+        return header.getBytes(StandardCharsets.ISO_8859_1);
+    }
+
+    private byte[] packBody(TxMessage msg) {
+        try {
+            ObjectNode node = objectMapper.createObjectNode();
+            if (msg.getTxId() != null) node.put("TXID", msg.getTxId());
+            if (msg.getMerchantId() != null) node.put("MERCHANTID", msg.getMerchantId());
+            if (msg.getTerminalId() != null) node.put("TERMINALID", msg.getTerminalId());
+            if (msg.getAmount() != null) node.put("AMOUNT", msg.getAmount());
+            if (msg.getStatus() != null) node.put("STATUS", msg.getStatus());
+            if (msg.getTranDate() != null) node.put("TRANDATE", msg.getTranDate());
+            if (msg.getTranTime() != null) node.put("TRANTIME", msg.getTranTime());
+            if (msg.getAuthNo() != null) node.put("AUTHNO", msg.getAuthNo());
+            if (msg.getCardNo() != null) node.put("CARDNO", maskCardNo(msg.getCardNo()));
+            if (msg.getVanMsg() != null) node.put("VANMSG", msg.getVanMsg());
+
+            msg.getExtra().forEach(node::put);
+            return objectMapper.writeValueAsString(node).getBytes(StandardCharsets.ISO_8859_1);
+        } catch (Exception e) {
+            throw new RuntimeException("Failed to pack message body", e);
+        }
+    }
+
+    private String maskCardNo(String cardNo) {
+        if (cardNo == null || cardNo.length() < 10) return cardNo;
+        return cardNo.substring(0, 6) + "****" + cardNo.substring(cardNo.length() - 4);
+    }
+}