将「增量同步」改为可配置选项，以解决一些已知的问题

Author: iBenzene

Image Downloader/HistoryManager.swift

@@ -186,13 +186,17 @@ class HistoryManager: ObservableObject {
                 // Conflict resolution: Remote wins if newer (or backend logic implies remote is truth)
                 let local = items[index]
                 if remote.updatedAt >= local.updatedAt {
+                    logDebug("History Merge [Update]: \(remote.id) - Local isDeleted: \(local.isDeleted) -> Remote isDeleted: \(remote.isDeleted) (Remote updatedAt: \(remote.updatedAt) >= Local: \(local.updatedAt))")
                     var merged = remote
                     merged.isDirty = false
                     items[index] = merged
                     needsSave = true
+                } else {
+                    logDebug("History Merge [Skip]: \(remote.id) - Remote updatedAt: \(remote.updatedAt) < Local: \(local.updatedAt)")
                 }
             } else {
                 // Insert new record
+                logDebug("History Merge [New]: \(remote.id) - isDeleted: \(remote.isDeleted)")
                 var newRecord = remote
                 newRecord.isDirty = false
                 items.append(newRecord)

Image Downloader/HistorySyncManager.swift

@@ -51,6 +51,10 @@ struct HistoryItemAPI: Codable {
         let timestampDate = formatter.date(from: created_at) ?? Date()
         let updatedAtDate = formatter.date(from: updated_at) ?? Date()
 
+        if is_deleted {
+            logDebug("Parsing Remote History Item: \(id) - URL: \(url.prefix(20))... - is_deleted: \(is_deleted), updated_at: \(updated_at)")
+        }
+        
         return HistoryItem(
             id: id,
             url: url,
@@ -105,9 +109,12 @@ class HistorySyncManager: ObservableObject {
 
         var queryItems = [URLQueryItem(name: "token", value: backendToken)]
 
-        if let lastSynced = HistoryManager.shared.lastSyncedAt {
+        let incrementalSync = UserDefaults.standard.bool(forKey: "incrementalSync")
+        if incrementalSync, let lastSynced = HistoryManager.shared.lastSyncedAt {
             let encodedDate = ISO8601DateFormatter.string(from: lastSynced, timeZone: TimeZone(secondsFromGMT: 0)!, formatOptions: [.withInternetDateTime, .withFractionalSeconds])
             queryItems.append(URLQueryItem(name: "since", value: encodedDate))
+        } else if !incrementalSync {
+            logDebug("Performing full history sync (Incremental sync disabled)")
         }
 
         components.queryItems = queryItems
@@ -147,6 +154,8 @@ class HistorySyncManager: ObservableObject {
             // 4. Handle Response
             let syncResponse = try JSONDecoder().decode(SyncResponse.self, from: data)
 
+            logDebug("Pulled \(syncResponse.records.count) history records from remote. SyncedAt: \(syncResponse.syncedAt)")
+            
             // Process Remote Records
             let remoteRecords = syncResponse.records.map { $0.toLocalItem() }
 

Image Downloader/SavedLinksManager.swift

@@ -235,12 +235,16 @@ class SavedLinksManager: ObservableObject {
             if let index = items.firstIndex(where: { $0.id == remote.id }) {
                 let local = items[index]
                 if remote.updatedAt >= local.updatedAt {
+                    logDebug("Merge [Update]: \(remote.id) - Local isDeleted: \(local.isDeleted) -> Remote isDeleted: \(remote.isDeleted) (Remote updatedAt: \(remote.updatedAt) >= Local: \(local.updatedAt))")
                     var merged = remote
                     merged.isDirty = false
                     items[index] = merged
                     needsSave = true
+                } else {
+                    logDebug("Merge [Skip]: \(remote.id) - Remote updatedAt: \(remote.updatedAt) < Local: \(local.updatedAt)")
                 }
             } else {
+                logDebug("Merge [New]: \(remote.id) - isDeleted: \(remote.isDeleted)")
                 var newRecord = remote
                 newRecord.isDirty = false
                 items.append(newRecord)

Image Downloader/SavedLinksSyncManager.swift

@@ -48,6 +48,10 @@ struct SavedLinkItemAPI: Codable {
         let updatedAtDate = formatter.date(from: updated_at) ?? Date()
         let parsedStatus = SavedLinkStatus(rawValue: status) ?? .none
 
+        if is_deleted {
+            logDebug("Parsing Remote Item: \(id) - URL: \(url.prefix(20))... - is_deleted: \(is_deleted), updated_at: \(updated_at)")
+        }
+        
         return SavedLinkItem(
             id: id,
             url: url,
@@ -98,9 +102,12 @@ class SavedLinksSyncManager: ObservableObject {
 
         var queryItems = [URLQueryItem(name: "token", value: backendToken)]
 
-        if let lastSynced = SavedLinksManager.shared.lastSyncedAt {
+        let incrementalSync = UserDefaults.standard.bool(forKey: "incrementalSync")
+        if incrementalSync, let lastSynced = SavedLinksManager.shared.lastSyncedAt {
             let encodedDate = ISO8601DateFormatter.string(from: lastSynced, timeZone: TimeZone(secondsFromGMT: 0)!, formatOptions: [.withInternetDateTime, .withFractionalSeconds])
             queryItems.append(URLQueryItem(name: "since", value: encodedDate))
+        } else if !incrementalSync {
+            logDebug("Performing full SavedLinks sync (Incremental sync disabled)")
         }
 
         components.queryItems = queryItems
@@ -138,6 +145,8 @@ class SavedLinksSyncManager: ObservableObject {
 
             let syncResponse = try JSONDecoder().decode(SavedLinksSyncResponse.self, from: data)
 
+            logDebug("Pulled \(syncResponse.records.count) records from remote. SyncedAt: \(syncResponse.syncedAt)")
+            
             let remoteRecords = syncResponse.records.map { $0.toLocalItem() }
 
             await MainActor.run {

Image Downloader/SettingsView.swift

@@ -12,6 +12,7 @@ struct SettingsView: View {
     @AppStorage("backendUrl") private var backendUrl: String = ""
     @AppStorage("backendToken") private var backendToken: String = ""
     @AppStorage("saveLinksOnly") private var saveLinksOnly: Bool = false
+    @AppStorage("incrementalSync") private var incrementalSync: Bool = true
     @AppStorage("logDisplayLevel") private var logDisplayLevel: Int = 1
 
     var body: some View {
@@ -27,6 +28,10 @@ struct SettingsView: View {
             Section(header: Text("收藏模式").textCase(nil), footer: Text("开启后，首页的「下载」按钮将被替换为「收藏」，仅提取并保存有效链接而不下载资源。")) {
                 Toggle("仅保存链接", isOn: $saveLinksOnly)
             }
+
+            Section(header: Text("同步").textCase(nil), footer: Text("开启增量同步将仅获取自上次同步以来的更新。为节约您的流量，建议保持开启状态。")) {
+                Toggle("增量同步", isOn: $incrementalSync)
+            }
 
             Section(header: Text("日志").textCase(nil), footer: Text("如果遇到问题，可以查看日志以获取更多信息。")) {
                 Picker(selection: $logDisplayLevel) {