[feature/Inhabas#234] 첨부파일 분류 기능 구현

resource-server/src/main/java/com/inhabas/api/global/util/ClassifiedFiles.java

@@ -0,0 +1,39 @@
+package com.inhabas.api.global.util;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import com.inhabas.api.domain.file.dto.FileDownloadDto;
+
+// ClassifyFiles 에 의해 분류된 파일들이 ClassifiedFiles 형태로 반환됨.
+public class ClassifiedFiles {
+  private FileDownloadDto thumbnail;
+  private List<FileDownloadDto> images = new ArrayList<>();
+  private List<FileDownloadDto> otherFiles = new ArrayList<>();
+
+  public ClassifiedFiles() {}
+
+  public FileDownloadDto getThumbnail() {
+    return thumbnail;
+  }
+
+  public List<FileDownloadDto> getImages() {
+    return images;
+  }
+
+  public List<FileDownloadDto> getOtherFiles() {
+    return otherFiles;
+  }
+
+  public void setThumbnail(FileDownloadDto thumbnail) {
+    this.thumbnail = thumbnail;
+  }
+
+  public void addImage(FileDownloadDto image) {
+    this.images.add(image);
+  }
+
+  public void addOtherFile(FileDownloadDto file) {
+    this.otherFiles.add(file);
+  }
+}

resource-server/src/main/java/com/inhabas/api/global/util/ClassifyFiles.java

@@ -0,0 +1,28 @@
+package com.inhabas.api.global.util;
+
+import java.util.List;
+
+import com.inhabas.api.domain.file.domain.BoardFile;
+import com.inhabas.api.domain.file.dto.FileDownloadDto;
+
+// 첨부파일을  썸네일, 이미지, (이미지가 아닌) 기타 파일로 분류
+public class ClassifyFiles {
+
+  public static ClassifiedFiles classifyFiles(List<BoardFile> files) {
+    ClassifiedFiles result = new ClassifiedFiles();
+
+    for (BoardFile file : files) {
+      FileDownloadDto fileDto = new FileDownloadDto(file.getName(), file.getUrl());
+      if (FileUtil.isImageFile(file.getName())) {
+        result.addImage(fileDto);
+        if (result.getThumbnail() == null) {
+          result.setThumbnail(fileDto); // 첫 번째 이미지 파일을 썸네일로 선택
+        }
+      } else {
+        result.addOtherFile(fileDto);
+      }
+    }
+
+    return result;
+  }
+}

resource-server/src/main/java/com/inhabas/api/global/util/FileUtil.java

@@ -14,6 +14,8 @@ public class FileUtil {
     "exe", "bat", "cmd", "sh", "js", "jsp", "php", "asp", "html"
   };
 
+  private static final String[] IMAGE_EXTENSIONS = {"jpg", "jpeg", "png", "gif", "bmp", "webp"};
+
   public static boolean isValidFileName(String fileName) {
 
     if (fileName == null || fileName.trim().isEmpty()) {
@@ -49,6 +51,16 @@ public static boolean isValidFileName(String fileName) {
     return true;
   }
 
+  public static boolean isImageFile(String fileName) {
+    String extension = getExtension(fileName).toLowerCase();
+    for (String imageExtension : IMAGE_EXTENSIONS) {
+      if (extension.equals(imageExtension)) {
+        return true;
+      }
+    }
+    return false;
+  }
+
   public static String getExtension(String fileName) {
     int lastIndex = fileName.lastIndexOf(".");
     if (lastIndex > 0) {