Fixed major issue with sync logic. Should be stable now. Solidified with

tests... turns out syncing is hard...

android/app/src/main/java/com/atridad/openclimb/data/sync/SyncService.kt

@@ -595,19 +595,29 @@ class SyncService(private val context: Context, private val repository: ClimbRep
 
         repository.resetAllData()
 
+        // Filter out deleted gyms before importing
+        val deletedGymIds = backup.deletedItems.filter { it.type == "gym" }.map { it.id }.toSet()
         backup.gyms.forEach { backupGym ->
             try {
+                if (!deletedGymIds.contains(backupGym.id)) {
                     val gym = backupGym.toGym()
                     Log.d(TAG, "Importing gym: ${gym.name} (ID: ${gym.id})")
                     repository.insertGymWithoutSync(gym)
+                } else {
+                    Log.d(TAG, "Skipping import of deleted gym: ${backupGym.id}")
+                }
             } catch (e: Exception) {
                 Log.e(TAG, "Failed to import gym '${backupGym.name}': ${e.message}")
                 throw e
             }
         }
 
+        // Filter out deleted problems before importing
+        val deletedProblemIds =
+                backup.deletedItems.filter { it.type == "problem" }.map { it.id }.toSet()
         backup.problems.forEach { backupProblem ->
             try {
+                if (!deletedProblemIds.contains(backupProblem.id)) {
                     val updatedProblem =
                             if (imagePathMapping.isNotEmpty()) {
                                 val newImagePaths =
@@ -626,7 +636,8 @@ class SyncService(private val context: Context, private val repository: ClimbRep
                                                                         oldPath
                                                                 )
                                                         val consistentFilename =
-                                                            ImageNamingUtils.generateImageFilename(
+                                                                ImageNamingUtils
+                                                                        .generateImageFilename(
                                                                                 backupProblem.id,
                                                                                 index
                                                                         )
@@ -639,22 +650,39 @@ class SyncService(private val context: Context, private val repository: ClimbRep
                                 backupProblem
                             }
                     repository.insertProblemWithoutSync(updatedProblem.toProblem())
+                } else {
+                    Log.d(TAG, "Skipping import of deleted problem: ${backupProblem.id}")
+                }
             } catch (e: Exception) {
                 Log.e(TAG, "Failed to import problem '${backupProblem.name}': ${e.message}")
             }
         }
 
+        // Filter out deleted sessions before importing
+        val deletedSessionIds =
+                backup.deletedItems.filter { it.type == "session" }.map { it.id }.toSet()
         backup.sessions.forEach { backupSession ->
             try {
+                if (!deletedSessionIds.contains(backupSession.id)) {
                     repository.insertSessionWithoutSync(backupSession.toClimbSession())
+                } else {
+                    Log.d(TAG, "Skipping import of deleted session: ${backupSession.id}")
+                }
             } catch (e: Exception) {
                 Log.e(TAG, "Failed to import session '${backupSession.id}': ${e.message}")
             }
         }
 
+        // Filter out deleted attempts before importing
+        val deletedAttemptIds =
+                backup.deletedItems.filter { it.type == "attempt" }.map { it.id }.toSet()
         backup.attempts.forEach { backupAttempt ->
             try {
+                if (!deletedAttemptIds.contains(backupAttempt.id)) {
                     repository.insertAttemptWithoutSync(backupAttempt.toAttempt())
+                } else {
+                    Log.d(TAG, "Skipping import of deleted attempt: ${backupAttempt.id}")
+                }
             } catch (e: Exception) {
                 Log.e(TAG, "Failed to import attempt '${backupAttempt.id}': ${e.message}")
             }
@@ -678,6 +706,19 @@ class SyncService(private val context: Context, private val repository: ClimbRep
             }
         }
 
+        // Import deletion records to prevent future resurrections
+        backup.deletedItems.forEach { deletion ->
+            try {
+                val deletionJson = json.encodeToString(deletion)
+                val preferences =
+                        context.getSharedPreferences("deleted_items", Context.MODE_PRIVATE)
+                preferences.edit { putString("deleted_${deletion.id}", deletionJson) }
+                Log.d(TAG, "Imported deletion record: ${deletion.type} ${deletion.id}")
+            } catch (e: Exception) {
+                Log.e(TAG, "Failed to import deletion record: ${e.message}")
+            }
+        }
+
         dataStateManager.setLastModified(backup.exportedAt)
         Log.d(TAG, "Data state synchronized to imported timestamp: ${backup.exportedAt}")
     }
@@ -694,10 +735,27 @@ class SyncService(private val context: Context, private val repository: ClimbRep
         val localSessions = repository.getAllSessions().first()
         val localAttempts = repository.getAllAttempts().first()
 
-        // Store active sessions before clearing
+        // Store active sessions before clearing (but exclude any that were deleted)
-        val activeSessions = localSessions.filter { it.status == SessionStatus.ACTIVE }
+        val localDeletedItems = repository.getDeletedItems()
+        val allDeletedSessionIds =
+                (serverBackup.deletedItems + localDeletedItems)
+                        .filter { it.type == "session" }
+                        .map { it.id }
+                        .toSet()
+        val activeSessions =
+                localSessions.filter {
+                    it.status == SessionStatus.ACTIVE && !allDeletedSessionIds.contains(it.id)
+                }
         val activeSessionIds = activeSessions.map { it.id }.toSet()
-        val activeAttempts = localAttempts.filter { activeSessionIds.contains(it.sessionId) }
+        val allDeletedAttemptIds =
+                (serverBackup.deletedItems + localDeletedItems)
+                        .filter { it.type == "attempt" }
+                        .map { it.id }
+                        .toSet()
+        val activeAttempts =
+                localAttempts.filter {
+                    activeSessionIds.contains(it.sessionId) && !allDeletedAttemptIds.contains(it.id)
+                }
 
         Log.d(TAG, "Merging data...")
         val mergedGyms = mergeGyms(localGyms, serverBackup.gyms, serverBackup.deletedItems)
@@ -772,9 +830,15 @@ class SyncService(private val context: Context, private val repository: ClimbRep
         // Clear and update local deletions with merged list
         repository.clearDeletedItems()
         allDeletions.forEach { deletion ->
-            // Re-add merged deletions to local store
+            try {
-            // Note: This is a simplified approach - in production you might want a more
+                val deletionJson = json.encodeToString(deletion)
-            // sophisticated merge
+                val preferences =
+                        context.getSharedPreferences("deleted_items", Context.MODE_PRIVATE)
+                preferences.edit { putString("deleted_${deletion.id}", deletionJson) }
+                Log.d(TAG, "Merged deletion record: ${deletion.type} ${deletion.id}")
+            } catch (e: Exception) {
+                Log.e(TAG, "Failed to save merged deletion: ${e.message}")
+            }
         }
 
         // Upload merged data back to server

ios/OpenClimb/Services/SyncService.swift

@@ -465,11 +465,25 @@ class SyncService: ObservableObject {
         imagePathMapping: [String: String] = [:]
     ) throws {
         do {
-            // Store active sessions and their attempts before import
+            // Store active sessions and their attempts before import (but exclude any that were deleted)
-            let activeSessions = dataManager.sessions.filter { $0.status == .active }
+            let localDeletedItems = dataManager.getDeletedItems()
+            let allDeletedSessionIds = Set(
+                (backup.deletedItems + localDeletedItems)
+                    .filter { $0.type == "session" }
+                    .map { $0.id }
+            )
+            let activeSessions = dataManager.sessions.filter {
+                $0.status == .active && !allDeletedSessionIds.contains($0.id.uuidString)
+            }
             let activeSessionIds = Set(activeSessions.map { $0.id })
+            let allDeletedAttemptIds = Set(
+                (backup.deletedItems + localDeletedItems)
+                    .filter { $0.type == "attempt" }
+                    .map { $0.id }
+            )
             let activeAttempts = dataManager.attempts.filter {
                 activeSessionIds.contains($0.sessionId)
+                    && !allDeletedAttemptIds.contains($0.id.uuidString)
             }
 
             print(
@@ -500,18 +514,58 @@ class SyncService: ObservableObject {
                         updatedAt: problem.updatedAt
                     )
                 }
+                // Filter out deleted items before creating updated backup
+                let deletedGymIds = Set(
+                    backup.deletedItems.filter { $0.type == "gym" }.map { $0.id })
+                let deletedProblemIds = Set(
+                    backup.deletedItems.filter { $0.type == "problem" }.map { $0.id })
+                let deletedSessionIds = Set(
+                    backup.deletedItems.filter { $0.type == "session" }.map { $0.id })
+                let deletedAttemptIds = Set(
+                    backup.deletedItems.filter { $0.type == "attempt" }.map { $0.id })
+
+                let filteredGyms = backup.gyms.filter { !deletedGymIds.contains($0.id) }
+                let filteredProblems = updatedProblems.filter { !deletedProblemIds.contains($0.id) }
+                let filteredSessions = backup.sessions.filter { !deletedSessionIds.contains($0.id) }
+                let filteredAttempts = backup.attempts.filter { !deletedAttemptIds.contains($0.id) }
+
                 updatedBackup = ClimbDataBackup(
                     exportedAt: backup.exportedAt,
                     version: backup.version,
                     formatVersion: backup.formatVersion,
-                    gyms: backup.gyms,
+                    gyms: filteredGyms,
-                    problems: updatedProblems,
+                    problems: filteredProblems,
-                    sessions: backup.sessions,
+                    sessions: filteredSessions,
-                    attempts: backup.attempts
+                    attempts: filteredAttempts,
+                    deletedItems: backup.deletedItems
                 )
 
             } else {
-                updatedBackup = backup
+                // Filter out deleted items even when no image path mapping
+                let deletedGymIds = Set(
+                    backup.deletedItems.filter { $0.type == "gym" }.map { $0.id })
+                let deletedProblemIds = Set(
+                    backup.deletedItems.filter { $0.type == "problem" }.map { $0.id })
+                let deletedSessionIds = Set(
+                    backup.deletedItems.filter { $0.type == "session" }.map { $0.id })
+                let deletedAttemptIds = Set(
+                    backup.deletedItems.filter { $0.type == "attempt" }.map { $0.id })
+
+                let filteredGyms = backup.gyms.filter { !deletedGymIds.contains($0.id) }
+                let filteredProblems = backup.problems.filter { !deletedProblemIds.contains($0.id) }
+                let filteredSessions = backup.sessions.filter { !deletedSessionIds.contains($0.id) }
+                let filteredAttempts = backup.attempts.filter { !deletedAttemptIds.contains($0.id) }
+
+                updatedBackup = ClimbDataBackup(
+                    exportedAt: backup.exportedAt,
+                    version: backup.version,
+                    formatVersion: backup.formatVersion,
+                    gyms: filteredGyms,
+                    problems: filteredProblems,
+                    sessions: filteredSessions,
+                    attempts: filteredAttempts,
+                    deletedItems: backup.deletedItems
+                )
             }
 
             // Create a minimal ZIP with just the JSON data for existing import mechanism
@@ -538,6 +592,13 @@ class SyncService: ObservableObject {
             dataManager.saveAttempts()
             dataManager.saveActiveSession()
 
+            // Import deletion records to prevent future resurrections
+            dataManager.clearDeletedItems()
+            if let data = try? JSONEncoder().encode(backup.deletedItems) {
+                UserDefaults.standard.set(data, forKey: "openclimb_deleted_items")
+                print("iOS IMPORT: Imported \(backup.deletedItems.count) deletion records")
+            }
+
             // Update local data state to match imported data timestamp
             DataStateManager.shared.setLastModified(backup.exportedAt)
             print("Data state synchronized to imported timestamp: \(backup.exportedAt)")

ios/OpenClimb/ViewModels/ClimbingDataManager.swift

@@ -452,8 +452,6 @@ class ClimbingDataManager: ObservableObject {
 
         // Update Live Activity when attempt is deleted
         updateLiveActivityForActiveSession()
-
-        // Note: Attempts for active sessions are not synced until session is completed
     }
 
     func attempts(forSession sessionId: UUID) -> [Attempt] {