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