[Developer] #424 show VPD policy function source

src/main/java/com/cloudhandson/vpdbackoffice/service/VpdPolicyService.java

@@ -1,8 +1,10 @@
 package com.cloudhandson.vpdbackoffice.service;
 
+import com.cloudhandson.vpdbackoffice.domain.vpd.VpdFunctionSource;
 import com.cloudhandson.vpdbackoffice.domain.vpd.VpdPolicyView;
 import com.cloudhandson.vpdbackoffice.mapper.VpdPolicyMapper;
 import java.util.List;
+import java.util.Locale;
 import org.springframework.stereotype.Service;
 
 @Service
@@ -17,4 +19,33 @@ public class VpdPolicyService {
   public List<VpdPolicyView> findPolicies() {
     return mapper.findPolicies();
   }
+
+  public VpdFunctionSource findFunctionSource(String owner, String packageName, String functionName) {
+    String normalizedOwner = requiredIdentifier(owner, "Function owner");
+    String normalizedFunction = requiredIdentifier(functionName, "Function name");
+    String normalizedPackage = normalizeOptionalIdentifier(packageName);
+    String objectName = normalizedPackage == null ? normalizedFunction : normalizedPackage;
+    String objectType = normalizedPackage == null ? "FUNCTION" : "PACKAGE BODY";
+    String source = mapper.findFunctionSource(normalizedOwner, objectName, objectType);
+    return new VpdFunctionSource(normalizedOwner, objectName, objectType, source);
+  }
+
+  private String requiredIdentifier(String value, String label) {
+    String normalized = normalizeOptionalIdentifier(value);
+    if (normalized == null) {
+      throw new AppException(label + " 값이 없습니다.");
+    }
+    return normalized;
+  }
+
+  private String normalizeOptionalIdentifier(String value) {
+    if (value == null || value.isBlank()) {
+      return null;
+    }
+    String normalized = value.trim().toUpperCase(Locale.ROOT);
+    if (!normalized.matches("[A-Z][A-Z0-9_$#]{0,127}")) {
+      throw new AppException("Oracle identifier 형식이 올바르지 않습니다: " + value);
+    }
+    return normalized;
+  }
 }