feat: 添加云盘与消息中心功能

suixinkan/Features/CloudDrive/Services/CloudTransferJSONStore.swift

@@ -0,0 +1,44 @@
+//
+//  CloudTransferJSONStore.swift
+//  suixinkan
+//
+
+import Foundation
+
+/// JSON 文件实现的云盘传输任务存储。
+final class CloudTransferJSONStore: CloudTransferTaskStoring {
+    private let fileURL: URL
+    private let encoder = JSONEncoder()
+    private let decoder = JSONDecoder()
+
+    /// 初始化本地 JSON 存储。
+    init(fileURL: URL? = nil) {
+        if let fileURL {
+            self.fileURL = fileURL
+        } else {
+            let baseURL = FileManager.default.urls(for: .applicationSupportDirectory, in: .userDomainMask).first
+                ?? FileManager.default.temporaryDirectory
+            self.fileURL = baseURL
+                .appendingPathComponent("suixinkan", isDirectory: true)
+                .appendingPathComponent("cloud_transfer_tasks.json")
+        }
+    }
+
+    func loadTasks() -> [CloudTransferTask] {
+        guard let data = try? Data(contentsOf: fileURL) else { return [] }
+        return (try? decoder.decode([CloudTransferTask].self, from: data)) ?? []
+    }
+
+    func saveTasks(_ tasks: [CloudTransferTask]) {
+        do {
+            let directory = fileURL.deletingLastPathComponent()
+            try FileManager.default.createDirectory(at: directory, withIntermediateDirectories: true)
+            let data = try encoder.encode(tasks)
+            try data.write(to: fileURL, options: [.atomic])
+        } catch {
+            #if DEBUG
+            print("CloudTransferJSONStore save failed: \(error)")
+            #endif
+        }
+    }
+}