初步实现文件的缓存管理

dimensionhub/Core/CacheManager.swift

@@ -0,0 +1,75 @@
+//
+//  CacheManager.swift
+//  dimensionhub
+//
+//  Created by 安礼成 on 2025/4/13.
+//
+
+import Foundation
+import CommonCrypto
+
+final class CacheManager {
+    
+    static let shared = CacheManager()
+    
+    private let cacheDir: URL
+    
+    private init() {
+        let paths = FileManager.default.urls(for: .cachesDirectory, in: .userDomainMask)
+        self.cacheDir = paths[0]
+    }
+    
+    func preloadImages(urls: [String]) async throws {
+        // 批量异步加载
+        try await withThrowingTaskGroup(of: Void.self) { group in
+            for url in urls {
+                group.addTask {
+                    if let data = try? await self.downloadImage(from: url) {
+                        try? self.saveCacheFile(filename: "xx", data: data)
+                    }
+                }
+            }
+            try await group.waitForAll()
+        }
+    }
+    
+    // 保存文件到缓存
+    private func saveCacheFile(filename: String, data: Data) throws {
+        let fileURL = cacheDir.appendingPathComponent(filename)
+        try data.write(to: fileURL)
+    }
+    
+    // 下载图片
+    private func downloadImage(from urlString: String) async throws -> Data? {
+        guard let url = URL(string: urlString) else {
+            return nil
+        }
+        
+        let request = URLRequest(url: url, timeoutInterval: 5000)
+        let (data, response) = try await URLSession.shared.data(for: request)
+        guard let response = response as? HTTPURLResponse, response.statusCode == 200 else {
+            return nil
+        }
+        
+        return data
+    }
+    
+    // 获取缓存的文件名
+    func getCacheFileName(urlString: String) -> String? {
+        guard let url = URL(string: urlString) else {
+            return nil
+        }
+        
+        return sha256(str: urlString) + "." + url.pathExtension.lowercased()
+    }
+    
+    private func sha256(str: String) -> String {
+        let data = Data(str.utf8)
+        var hash = [UInt8](repeating: 0, count: Int(CC_SHA256_DIGEST_LENGTH))
+        data.withUnsafeBytes { bytes in
+            _ = CC_SHA256(bytes.baseAddress, CC_LONG(data.count), &hash)
+        }
+        return hash.map { String(format: "%02hhx", $0) }.joined()
+    }
+    
+}

dimensionhub/Views/Index/IndexMainView.swift

@@ -80,7 +80,6 @@ struct IndexMainView: View {
             }
             .frame(width: 370)
             .coordinateSpace(name: "indexScrollView")
-            
             .onPreferenceChange(FooterOffsetPreferenceKey.self) { offset in
                 // 延迟到当前帧结束更新state的值，避免导致循环更新的警告
                 DispatchQueue.main.async {
@@ -143,6 +142,11 @@ struct IndexMainView: View {
         .onPreferenceChange(DramaGroupElementPreferenceKey.self) { frames in
             indexModel.visiblePublisher.send(frames)
         }
+        .onAppear {
+            let x = CacheManager.shared.getCacheFileName(urlString: "https://www.baidu.com/x/y/z.jpg?ts=1234")
+            let x1 = CacheManager.shared.getCacheFileName(urlString: "https://www.baidu.com/x/y/z.jpg")
+            print("x: \(x), x1: \(x1)")
+        }
         
     }