#1331 커버 이미지를 선택할 수 있는 기능 추가

- files 테이블에 cover_image 컬럼 추가
- 썸네일 생성 로직에 cover_image 값을 참조하여 이미지 선택 사용
- 파일 업로드 기능에 UI 추가

modules/comment/comment.item.php

@@ -543,6 +543,11 @@ class commentItem extends Object
 			return;
 		}
 
+		if($this->isSecret() && !$this->isGranted())
+		{
+			return;
+		}
+
 		// If signiture height setting is omitted, create a square
 		if(!$height)
 		{
@@ -587,30 +592,33 @@ class commentItem extends Object
 		if($this->hasUploadedFiles())
 		{
 			$file_list = $this->getUploadedFiles();
-			if(count($file_list))
-			{
-				foreach($file_list as $file)
-				{
-					if($file->direct_download != 'Y')
-					{
-						continue;
-					}
-					if(!preg_match("/\.(jpg|png|jpeg|gif|bmp)$/i", $file->source_filename))
-					{
-						continue;
-					}
 
+			$first_image = null;
+			foreach($file_list as $file)
+			{
+				if($file->direct_download !== 'Y') continue;
+
+				if($file->cover_image === 'Y' && file_exists($file->uploaded_filename))
+				{
 					$source_file = $file->uploaded_filename;
-					if(!file_exists($source_file))
+					break;
+				}
+
+				if($first_image) continue;
+
+				if(preg_match("/\.(jpe?g|png|gif|bmp)$/i", $file->source_filename))
+				{
+					if(file_exists($file->uploaded_filename))
 					{
-						$source_file = NULL;
-					}
-					else
-					{
-						break;
+						$first_image = $file->uploaded_filename;
 					}
 				}
 			}
+
+			if(!$source_file && $first_image)
+			{
+				$source_file = $first_image;
+			}
 		}
 
 		// get an image file from the doc content if no file attached.