Save GIFs Locally

GIFCollector MessagesExtension/Services/DownloadService.swift

@@ -0,0 +1,60 @@
+import Foundation
+import UIKit
+
+class DownloadService {
+    static let shared = DownloadService()
+    
+    private let cache = NSCache<NSString, NSData>()
+    private var activeTasks: [URL: URLSessionDataTask] = [:]
+    
+    private init() {
+        cache.totalCostLimit = 50 * 1024 * 1024 // 50 MB cache limit
+    }
+    
+    func downloadGIF(from urlString: String, completion: @escaping (Data?, Error?) -> Void) {
+        guard let url = URL(string: urlString) else {
+            completion(nil, NSError(domain: "DownloadService", code: 1, userInfo: [NSLocalizedDescriptionKey: "Invalid URL"]))
+            return
+        }
+        
+        // Check if the GIF is already cached
+        let cacheKey = url.absoluteString as NSString
+        if let cachedData = cache.object(forKey: cacheKey) {
+            completion(cachedData as Data, nil)
+            return
+        }
+        
+        // Cancel any existing tasks for this URL
+        activeTasks[url]?.cancel()
+        
+        // Create a new download task
+        let task = URLSession.shared.dataTask(with: url) { [weak self] data, response, error in
+            defer {
+                self?.activeTasks.removeValue(forKey: url)
+            }
+            
+            guard let self = self, error == nil, let data = data else {
+                DispatchQueue.main.async {
+                    completion(nil, error ?? NSError(domain: "DownloadService", code: 2, userInfo: [NSLocalizedDescriptionKey: "Failed to download GIF"]))
+                }
+                return
+            }
+            
+            // Cache the downloaded data
+            self.cache.setObject(data as NSData, forKey: cacheKey, cost: data.count)
+            
+            DispatchQueue.main.async {
+                completion(data, nil)
+            }
+        }
+        
+        // Store and start the task
+        activeTasks[url] = task
+        task.resume()
+    }
+    
+    func cancelAllTasks() {
+        activeTasks.values.forEach { $0.cancel() }
+        activeTasks.removeAll()
+    }
+}