[FIX] 이미지 블링크 문제 개선

Poppool/CoreLayer/Infrastructure/Infrastructure/Extension/UIImageView+.swift

@@ -1,34 +1,87 @@
+import ObjectiveC
 import UIKit
 
+private var currentURLKey: UInt8 = 0
+private var placeholderImageKey: UInt8 = 0
+
 public extension UIImageView {
+
+    private var currentImageURL: String? {
+        get { objc_getAssociatedObject(self, &currentURLKey) as? String }
+        set { objc_setAssociatedObject(self, &currentURLKey, newValue, .OBJC_ASSOCIATION_RETAIN_NONATOMIC) }
+    }
+
+    private var placeholderImage: UIImage? {
+        get { objc_getAssociatedObject(self, &placeholderImageKey) as? UIImage }
+        set { objc_setAssociatedObject(self, &placeholderImageKey, newValue, .OBJC_ASSOCIATION_RETAIN_NONATOMIC) }
+    }
+
     func setPPImage(path: String?) {
-        guard let path = path else {
-            self.image = UIImage(named: "image_default")
+        loadImageFromImageLoader(path: path, completion: nil)
+    }
+
+    func setPPImage(path: String?, completion: @escaping () -> Void) {
+        loadImageFromImageLoader(path: path, completion: completion)
+    }
+
+    func loadImageFromImageLoader(path: String?, completion: (() -> Void)? = nil) {
+        // 기본 이미지 저장
+        if placeholderImage == nil {
+            placeholderImage = UIImage(named: "image_default")
+            completion?()
+        }
+
+        guard let path = path, !path.isEmpty else {
+            image = placeholderImage
+            currentImageURL = nil
+            completion?()
             return
         }
+
         let imageURLString = Secrets.popPoolS3BaseURL + path
-        if let cenvertimageURL = imageURLString.addingPercentEncoding(withAllowedCharacters: .urlQueryAllowed) {
-            ImageLoader.shared.loadImage(with: cenvertimageURL, defaultImage: UIImage(named: "image_default"), imageQuality: .origin) { [weak self] image in
-                DispatchQueue.main.async {
-                    self?.image = image
-                }
-            }
+        guard let encodedURL = imageURLString.addingPercentEncoding(withAllowedCharacters: .urlQueryAllowed) else {
+            image = placeholderImage
+            currentImageURL = nil
+            completion?()
+            return
         }
-    }
 
-    func setPPImage(path: String?, completion: @escaping () -> Void) {
-        guard let path = path else {
-            self.image = UIImage(named: "image_default")
-            completion()
+        // 이미 같은 URL을 로딩했고 이미지가 있으면 재로딩 방지
+        if currentImageURL == encodedURL && self.image != nil && self.image != placeholderImage {
+            completion?()
             return
         }
-        let imageURLString = Secrets.popPoolS3BaseURL + path
-        if let cenvertimageURL = imageURLString.addingPercentEncoding(withAllowedCharacters: .urlQueryAllowed) {
-            let imageURL = URL(string: cenvertimageURL)
-            ImageLoader.shared.loadImage(with: cenvertimageURL, defaultImage: UIImage(named: "image_default"), imageQuality: .origin) { [weak self] image in
-                DispatchQueue.main.async {
-                    completion()
-                    self?.image = image
+
+        // 현재 이미지 URL을 업데이트
+        currentImageURL = encodedURL
+
+        // 먼저 메모리 캐시 확인
+        if let cachedImage = MemoryStorage.shared.fetchImage(url: encodedURL) {
+            self.image = cachedImage
+            completion?()
+            return
+        }
+
+        // 다음으로 디스크 캐시 확인
+        if let diskImage = DiskStorage.shared.fetchImage(url: encodedURL) {
+            MemoryStorage.shared.store(image: diskImage, url: encodedURL)
+            self.image = diskImage
+            completion?()
+            return
+        }
+
+        ImageLoader.shared.loadImage(with: encodedURL, defaultImage: placeholderImage, imageQuality: .origin) { [weak self] image in
+            guard let self else { return }
+            defer { completion?() }
+            DispatchQueue.main.async {
+                // 현재 요청 ID와 캡처된 ID가 일치하는지 확인 (다른 이미지로 변경되었으면 무시)
+                if self.currentImageURL == encodedURL {
+                    if let image = image {
+                        self.image = image
+                    } else if self.image == nil {
+                        // 이미지 로드 실패 시 기본 이미지 표시
+                        self.image = self.placeholderImage
+                    }
                 }
             }
         }