Warn if logout/delete would impact unsynced data

app/src/main/java/net/helcel/cowspent/android/account/AccountActivity.kt

@@ -1,7 +1,6 @@
 package net.helcel.cowspent.android.account
 
 import android.annotation.SuppressLint
-import android.content.Context
 import android.content.Intent
 import android.content.SharedPreferences
 import android.os.Build
@@ -38,6 +37,8 @@ import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
 import net.helcel.cowspent.R
 import net.helcel.cowspent.android.main.MainConstants
+import net.helcel.cowspent.persistence.CowspentSQLiteOpenHelper
+import net.helcel.cowspent.persistence.CowspentServerSyncHelper
 import net.helcel.cowspent.theme.ThemeUtils
 import net.helcel.cowspent.util.CospendClientUtil
 import net.helcel.cowspent.util.CospendClientUtil.LoginStatus
@@ -108,8 +109,7 @@ class AccountActivity : AppCompatActivity() {
                                 viewModel.useSso = false
                                 preferences.edit { putBoolean(SETTINGS_USE_SSO, false) }
                             }
-                        },
+                        }
-                        onLogout = { viewModel.logout() }
                     )
                 }
 
@@ -147,7 +147,7 @@ class AccountActivity : AppCompatActivity() {
                             allowFileAccess = false
                             javaScriptEnabled = true
                             domStorageEnabled = true
-                            userAgentString = getWebLoginUserAgent(context)
+                            userAgentString = getWebLoginUserAgent()
                         }
                         webViewClient = object : WebViewClient() {
                             @Deprecated("Deprecated in Java")
@@ -188,6 +188,12 @@ class AccountActivity : AppCompatActivity() {
         }
     }
 
+    private fun startInitialAccountSync() {
+        if (!CowspentServerSyncHelper.isNextcloudAccountConfigured(applicationContext)) return
+        CowspentSQLiteOpenHelper.getInstance(applicationContext)
+            .cowspentServerSyncHelper.runAccountProjectsSync()
+    }
+
     @Deprecated("Deprecated in Java")
     override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
         super.onActivityResult(requestCode, resultCode, data)
@@ -207,6 +213,8 @@ class AccountActivity : AppCompatActivity() {
                     viewModel.serverUrl = ssoAccount.url
                     viewModel.username = ssoAccount.userId
 
+                    startInitialAccountSync()
+
                     val resultData = Intent()
                     resultData.putExtra(MainConstants.CREDENTIALS_CHANGED, CREDENTIALS_CHANGED)
                     setResult(RESULT_OK, resultData)
@@ -234,13 +242,9 @@ class AccountActivity : AppCompatActivity() {
         }
     }
 
-    private fun getWebLoginUserAgent(context: Context): String {
+    private fun getWebLoginUserAgent(): String {
-        val defaultUA = try {
+        val manufacturer = Build.MANUFACTURER.replaceFirstChar { it.titlecase(Locale.ROOT) }
-            android.webkit.WebSettings.getDefaultUserAgent(context)
+        return "$manufacturer ${Build.MODEL} (Cowspent/Android)"
-        } catch (_: Exception) {
-            Build.MANUFACTURER + " " + Build.MODEL
-        }
-        return "$defaultUA Cowspent/Android"
     }
 
     private fun parseAndLoginFromWebView(dataString: String) {
@@ -312,6 +316,8 @@ class AccountActivity : AppCompatActivity() {
                     remove(SETTINGS_KEY_LAST_MODIFIED)
                 }
 
+                startInitialAccountSync()
+
                 val data = Intent()
                 data.putExtra(MainConstants.CREDENTIALS_CHANGED, CREDENTIALS_CHANGED)
                 setResult(RESULT_OK, data)

app/src/main/java/net/helcel/cowspent/android/account/AccountScreen.kt

@@ -14,6 +14,7 @@ import androidx.compose.runtime.Composable
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.res.pluralStringResource
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.text.input.PasswordVisualTransformation
@@ -28,8 +29,7 @@ fun AccountScreen(
     viewModel: AccountViewModel,
     onBack: () -> Unit,
     onConnect: () -> Unit,
-    onSsoClick: (Boolean) -> Unit,
+    onSsoClick: (Boolean) -> Unit
-    onLogout: () -> Unit
 ) {
     AccountScreenContent(
         isLoggedIn = viewModel.isLoggedIn,
@@ -51,7 +51,57 @@ fun AccountScreen(
         onBack = onBack,
         onConnect = onConnect,
         onSsoClick = onSsoClick,
-        onLogout = onLogout
+        onLogout = { viewModel.requestLogout() }
+    )
+
+    viewModel.logoutImpact?.let { impact ->
+        LogoutConfirmationDialog(
+            impact = impact,
+            onDismiss = { viewModel.cancelLogout() },
+            onConfirm = { viewModel.confirmLogout() }
+        )
+    }
+}
+
+@Composable
+fun LogoutConfirmationDialog(
+    impact: AccountViewModel.LogoutImpact,
+    onDismiss: () -> Unit,
+    onConfirm: () -> Unit
+) {
+    AlertDialog(
+        onDismissRequest = onDismiss,
+        title = { Text(stringResource(R.string.logout_confirm_title)) },
+        text = {
+            Column {
+                Text(
+                    if (impact.projects > 0) {
+                        pluralStringResource(
+                            R.plurals.logout_confirm_projects, impact.projects, impact.projects
+                        )
+                    } else {
+                        stringResource(R.string.logout_confirm_no_projects)
+                    }
+                )
+                if (impact.unsyncedBills > 0) {
+                    Spacer(Modifier.height(12.dp))
+                    Text(
+                        text = pluralStringResource(
+                            R.plurals.warning_unsynced_bills,
+                            impact.unsyncedBills,
+                            impact.unsyncedBills
+                        ),
+                        fontWeight = FontWeight.Bold
+                    )
+                }
+            }
+        },
+        confirmButton = {
+            TextButton(onClick = onConfirm) { Text(stringResource(R.string.action_logout)) }
+        },
+        dismissButton = {
+            TextButton(onClick = onDismiss) { Text(stringResource(R.string.simple_cancel)) }
+        }
     )
 }
 

app/src/main/java/net/helcel/cowspent/android/account/AccountViewModel.kt

@@ -2,9 +2,11 @@ package net.helcel.cowspent.android.account
 
 import android.app.Application
 import android.content.SharedPreferences
+import android.util.Log
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.setValue
+import androidx.annotation.VisibleForTesting
 import androidx.core.content.edit
 import androidx.lifecycle.AndroidViewModel
 import androidx.lifecycle.viewModelScope
@@ -12,10 +14,17 @@ import androidx.preference.PreferenceManager
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
+import net.helcel.cowspent.model.DBProject
+import net.helcel.cowspent.persistence.CowspentSQLiteOpenHelper
 import net.helcel.cowspent.util.CospendClientUtil
 import net.helcel.cowspent.util.SecureStorage
 
 class AccountViewModel(application: Application) : AndroidViewModel(application) {
+
+    private companion object {
+        const val TAG = "AccountViewModel"
+    }
+
     private val preferences: SharedPreferences = PreferenceManager.getDefaultSharedPreferences(application)
 
     var useSso by mutableStateOf(preferences.getBoolean(AccountActivity.SETTINGS_USE_SSO, false))
@@ -41,6 +50,9 @@ class AccountViewModel(application: Application) : AndroidViewModel(application)
     var showWebView by mutableStateOf(false)
 
     var isLoggedIn by mutableStateOf(false)
+
+    /** Non-null while the logout confirmation is up, carrying what it would cost. */
+    var logoutImpact by mutableStateOf<LogoutImpact?>(null)
         private set
 
     var isValidatingLogin by mutableStateOf(false)
@@ -88,8 +100,63 @@ class AccountViewModel(application: Application) : AndroidViewModel(application)
         }
     }
 
+    private fun projectsTheAccountProvided(db: CowspentSQLiteOpenHelper): List<DBProject> {
+        val offered = db.accountProjects
+        val cospendPath = "/index.php/apps/cospend"
+        return db.projects.filter { project ->
+            offered.any {
+                it.remoteId == project.remoteId &&
+                        project.serverUrl?.replace("/+$".toRegex(), "") ==
+                        it.ncUrl.replace("/+$".toRegex(), "") + cospendPath
+            }
+        }
+    }
+    data class LogoutImpact(val projects: Int, val unsyncedBills: Int)
+
+    private fun measureLogoutImpact(): LogoutImpact {
+        val db = CowspentSQLiteOpenHelper.getInstance(getApplication())
+        val projects = projectsTheAccountProvided(db)
+        val unsynced = projects.sumOf { db.countUnsyncedBills(it.id) }
+        return LogoutImpact(projects.size, unsynced)
+    }
+
+    fun requestLogout() {
+        viewModelScope.launch {
+            logoutImpact = withContext(Dispatchers.IO) {
+                try {
+                    measureLogoutImpact()
+                } catch (e: Exception) {
+                    // Never let a failed count block signing out - just ask without the detail.
+                    Log.e(TAG, "Could not measure what logging out would remove", e)
+                    LogoutImpact(0, 0)
+                }
+            }
+        }
+    }
+
+    fun cancelLogout() {
+        logoutImpact = null
+    }
+
+    fun confirmLogout() {
+        logoutImpact = null
+        logout()
+    }
+
+    private fun forgetProjectsTheAccountProvided() {
+        try {
+            val db = CowspentSQLiteOpenHelper.getInstance(getApplication())
+            projectsTheAccountProvided(db).forEach { db.deleteProject(it.id) }
+            db.clearAccountProjects()
+        } catch (e: Exception) {
+            Log.e(TAG, "Could not remove the account's projects on logout", e)
+        }
+    }
+
+    @VisibleForTesting
     fun logout() {
         viewModelScope.launch {
+            withContext(Dispatchers.IO) { forgetProjectsTheAccountProvided() }
             SecureStorage.removePassword(getApplication(), AccountActivity.SETTINGS_PASSWORD)
         }
         preferences.edit {

app/src/main/java/net/helcel/cowspent/android/label/LabelManagementScreen.kt

@@ -219,6 +219,7 @@ fun CategoryList(
                 onDelete = { onDelete(category) }
             )
         }
+        item { LabelListBottomSpacer() }
     }
 }
 
@@ -238,9 +239,19 @@ fun PaymentModeList(
                 onDelete = { onDelete(pm) }
             )
         }
+        item { LabelListBottomSpacer() }
     }
 }
 
+/**
+ * Keeps the last row clear of the add button, which otherwise sits on top of its delete icon and
+ * swallows the tap - with nothing below to scroll to, that row simply cannot be deleted.
+ */
+@Composable
+private fun LabelListBottomSpacer() {
+    Spacer(modifier = Modifier.height(64.dp).fillMaxWidth())
+}
+
 @Composable
 fun LabelItem(
     name: String,

app/src/main/java/net/helcel/cowspent/android/main/BillsListScreen.kt

@@ -132,6 +132,10 @@ fun BillsListScreen(
                     onProjectAction(projectOptionsProjectId, 1)
                     viewModel.showProjectOptionsDialogByProjectId = null
                 },
+                onForgetProject = {
+                    onProjectAction(projectOptionsProjectId, 9)
+                    viewModel.showProjectOptionsDialogByProjectId = null
+                },
                 onManageMembers = {
                     onProjectAction(projectOptionsProjectId, 2)
                     viewModel.showProjectOptionsDialogByProjectId = null
@@ -408,11 +412,9 @@ fun BillsListScreen(
             .pullRefresh(pullRefreshState)) {
             when {
                 viewModel.showNoProjects -> EmptyProjectsState(onAccountSwitcherClick, onAddProjectClick)
+               (viewModel.isRefreshing || viewModel.isLoadingBills) && viewModel.bills.isEmpty() ->
+                    LoadingBillsState()
                 viewModel.showNoMembers -> EmptyMembersState()
-                // A large project takes a long time on its first sync. Until that finishes there
-                // is nothing stored for it yet, and reporting that as "no bills" tells the user
-                // the project is empty when it is still downloading.
-                viewModel.isRefreshing && viewModel.bills.isEmpty() -> LoadingBillsState()
                 viewModel.showNoBills -> EmptyBillsState()
                 viewModel.bills.isEmpty() -> EmptyState()
                 else -> {

app/src/main/java/net/helcel/cowspent/android/main/BillsListViewActivity.kt

@@ -270,6 +270,7 @@ class BillsListViewActivity :
                             8 -> {
                                 startActivity(net.helcel.cowspent.android.label.LabelManagementActivity.createIntent(this@BillsListViewActivity, pid))
                             }
+                            9 -> onRemoveProjectClick(pid)
                         }
                     },
                     onAccountSwitcherClick = {
@@ -334,6 +335,7 @@ class BillsListViewActivity :
         super.onResume()
         val preferences = PreferenceManager.getDefaultSharedPreferences(applicationContext)
         val selectedProjectId = preferences.getLong("selected_project", 0)
+        setupDrawerProjects()
         if (selectedProjectId != 0L) {
             refreshLists()
         }
@@ -341,6 +343,10 @@ class BillsListViewActivity :
 
         synchronize(SyncTrigger.APP_OPEN)
 
+        lifecycleScope.launch {
+            syncNewlyDiscoveredProjects(withContext(Dispatchers.IO) { db.projects })
+        }
+
         registerBroadcastReceiver()
         updateAvatarInDrawer(CowspentServerSyncHelper.isNextcloudAccountConfigured(this))
         isActivityVisible = true
@@ -377,6 +383,8 @@ class BillsListViewActivity :
     fun onProjectClick(projectId: Long) {
         if (viewModel.selectedProjectId != projectId) {
             viewModel.selectedMemberId = null
+            viewModel.bills = emptyList()
+            viewModel.isLoadingBills = true
         }
         setSelectedProject(projectId)
         navigationSelection = Category(null, null)
@@ -400,16 +408,34 @@ class BillsListViewActivity :
     private fun onRemoveProjectClick(projectId: Long) {
         if (projectId == 0L) return
         lifecycleScope.launch {
-            val proj = withContext(Dispatchers.IO) { db.getProject(projectId) } ?: return@launch
+            val (proj, unsyncedBills) = withContext(Dispatchers.IO) {
+                val p = db.getProject(projectId) ?: return@withContext null
+                p to db.countUnsyncedBills(projectId)
+            } ?: return@launch
+
+            val message = buildString {
+                if (!proj.isLocal) append(getString(R.string.dialog_confirm_remove_project_msg))
+                if (unsyncedBills > 0) {
+                    if (isNotEmpty()) append("\n\n")
+                    append(
+                        resources.getQuantityString(
+                            R.plurals.warning_unsynced_bills, unsyncedBills, unsyncedBills
+                        )
+                    )
+                }
+            }
 
             viewModel.showDialog(
                 title = getString(R.string.title_confirm),
-                message = if (!proj.isLocal) getString(R.string.dialog_confirm_remove_project_msg) else null,
+                message = message.ifEmpty { null },
                 positiveText = getString(R.string.simple_yes),
                 onConfirm = {
                     lifecycleScope.launch {
                         withContext(Dispatchers.IO) {
                             db.deleteProject(projectId)
+                            // Otherwise the next account sync sees a project the account offers
+                            // with no local row, and creates it again.
+                            CowspentServerSyncHelper.forgetAccountProject(applicationContext, proj)
                             PreferenceManager.getDefaultSharedPreferences(applicationContext)
                                 .edit { remove(lastProjectSyncKey(projectId)) }
                             val dbProjects = db.projects
@@ -621,76 +647,80 @@ class BillsListViewActivity :
         val selectedProjectId = PreferenceManager.getDefaultSharedPreferences(applicationContext).getLong("selected_project", 0)
         
         lifecycleScope.launch {
-            val (projId, projName) = withContext(Dispatchers.IO) {
+            try {
-                if (selectedProjectId != 0L) {
+                val (projId, projName) = withContext(Dispatchers.IO) {
-                    db.getProject(selectedProjectId)?.let {
+                    if (selectedProjectId != 0L) {
-                        it.id to (if (it.name == "null" || it.name.isEmpty()) it.remoteId else it.name)
+                        db.getProject(selectedProjectId)?.let {
-                    } ?: (0L to "")
+                            it.id to (if (it.name == "null" || it.name.isEmpty()) it.remoteId else it.name)
-                } else {
+                        } ?: (0L to "")
-                    0L to ""
+                    } else {
-                }
+                        0L to ""
-            }
+                    }
-            
-            val title = if (selectedProjectId != 0L) projName else getString(R.string.app_name)
-            
-            setSelectedProject(selectedProjectId)
-            viewModel.title = title
-            val query = viewModel.searchQuery.ifEmpty { null }
-
-            val (ljItems, memberCount) = withContext(Dispatchers.IO) {
-                val db = CowspentSQLiteOpenHelper.getInstance(applicationContext)
-                val billList: List<DBBill> = if (projId != 0L) {
-                    db.searchBills(query, projId)
-                } else {
-                    ArrayList()
                 }
             
-                val bills = billList.filter {
+                val title = if (selectedProjectId != 0L) projName else getString(R.string.app_name)
-                    val mid = viewModel.selectedMemberId
+            
-                    mid == null || mid == it.payerId || it.billOwersIds.contains(mid)
+                setSelectedProject(selectedProjectId)
+                viewModel.title = title
+                val query = viewModel.searchQuery.ifEmpty { null }
+
+                val (ljItems, memberCount) = withContext(Dispatchers.IO) {
+                    val db = CowspentSQLiteOpenHelper.getInstance(applicationContext)
+                    val billList: List<DBBill> = if (projId != 0L) {
+                        db.searchBills(query, projId)
+                    } else {
+                        ArrayList()
+                    }
+
+                    val bills = billList.filter {
+                        val mid = viewModel.selectedMemberId
+                        mid == null || mid == it.payerId || it.billOwersIds.contains(mid)
+                    }
+
+                    viewModel.hasUnlabeledBills = bills.any { it.categoryId == 0L && it.state != DBBill.STATE_DELETED }
+
+                    val projectMembers = db.getMembersOfProject(projId, null)
+                    val memberMap = projectMembers.associateBy { it.id }
+
+                    val projectPaymentModes = db.getPaymentModes(projId).associateBy { it.id }
+                    val projectCategories = db.getCategories(projId).associateBy { it.id }
+
+                    BillFormatter.formatBills(
+                        bills,
+                        memberMap,
+                        projectCategories,
+                        projectPaymentModes
+                    )
+
+                    val sdf = SimpleDateFormat("yyyy-MM-dd", Locale.ROOT)
+                    val itemList = BillsListUtils.groupAndSectionBills(
+                        bills,
+                        memberMap,
+                        sdf,
+                        applicationContext
+                    )
+
+                    itemList to projectMembers.size
                 }
 
-                viewModel.hasUnlabeledBills = bills.any { it.categoryId == 0L && it.state != DBBill.STATE_DELETED }
+                viewModel.showNoProjects = false
+                viewModel.showNoMembers = false
+                viewModel.showNoBills = false
 
-                val projectMembers = db.getMembersOfProject(projId, null)
+                when {
-                val memberMap = projectMembers.associateBy { it.id }
+                    memberCount == 0 -> {
-
+                        viewModel.showNoMembers = true
-                val projectPaymentModes = db.getPaymentModes(projId).associateBy { it.id }
+                    }
-                val projectCategories = db.getCategories(projId).associateBy { it.id }
+                    ljItems.isEmpty() -> {
-
+                        viewModel.showNoBills = true
-                BillFormatter.formatBills(
+                        viewModel.bills = emptyList()
-                    bills,
+                    }
-                    memberMap,
+                    else -> {
-                    projectCategories,
+                        viewModel.bills = ljItems
-                    projectPaymentModes
+                    }
-                )
-
-                val sdf = SimpleDateFormat("yyyy-MM-dd", Locale.ROOT)
-                val itemList = BillsListUtils.groupAndSectionBills(
-                    bills,
-                    memberMap,
-                    sdf,
-                    applicationContext
-                )
-
-                itemList to projectMembers.size
-            }
-
-            viewModel.showNoProjects = false
-            viewModel.showNoMembers = false
-            viewModel.showNoBills = false
-            
-            when {
-                memberCount == 0 -> {
-                    viewModel.showNoMembers = true
-                }
-                ljItems.isEmpty() -> {
-                    viewModel.showNoBills = true
-                    viewModel.bills = emptyList()
-                }
-                else -> {
-                    viewModel.bills = ljItems
                 }
+            } finally {
+                viewModel.isLoadingBills = false
             }
         }
     }
@@ -780,16 +810,19 @@ class BillsListViewActivity :
         val selectedProjectId = preferences.getLong("selected_project", 0)
         val now = System.currentTimeMillis()
 
-        // The account and all-projects refresh belongs to opening the app, throttled by the
+        // The account tells the app which projects exist at all, so a project joined elsewhere only
-        // SyncOnOpen interval so that resuming within the interval does not repeat it.
+        // shows up once it has been read. That happens on login, on opening the app - throttled by
+        // the interval so resuming does not repeat it - and on a manual refresh, which is an
+        // explicit ask and so is never throttled.
         val intervalMinutes = SyncSettings.OPEN_SYNC_INTERVAL_MINUTES
         val lastAccountSync = preferences.getLong(getString(R.string.pref_key_last_account_sync_timestamp), 0L)
-        val accountSyncDue = trigger == SyncTrigger.APP_OPEN &&
+        val openPass = trigger == SyncTrigger.APP_OPEN &&
             now - lastAccountSync > intervalMinutes * 60 * 1000L
+        val accountSyncDue = openPass || trigger == SyncTrigger.MANUAL
 
         lifecycleScope.launch {
             val remoteProjects = withContext(Dispatchers.IO) { db.projects }
-                .filter { !it.isLocal && !it.isArchived }
+                .filter { !it.isLocal }
                 // Only the first one scheduled actually starts - the rest queue behind it - and it
                 // takes the screen's callback with it. So the selected project goes first: otherwise
                 // the spinner follows a project the user is not looking at, stops when that one
@@ -799,7 +832,11 @@ class BillsListViewActivity :
             viewModel.isRefreshing = true
             db.cowspentServerSyncHelper.addCallbackPull(syncCallBack)
 
-            val started = if (accountSyncDue) {
+            if (accountSyncDue && CowspentServerSyncHelper.isNextcloudAccountConfigured(applicationContext)) {
+                db.cowspentServerSyncHelper.runAccountProjectsSync()
+            }
+
+            val started = if (openPass) {
                 // The pass is throttled by this stamp, so it has to be written here rather than
                 // left to the account sync: that only runs when an account is configured and only
                 // records itself on success, so without one the stamp stayed at zero and the pass
@@ -807,12 +844,13 @@ class BillsListViewActivity :
                 preferences.edit {
                     putLong(getString(R.string.pref_key_last_account_sync_timestamp), now)
                 }
-                if (CowspentServerSyncHelper.isNextcloudAccountConfigured(applicationContext)) {
+                remoteProjects.filter { !it.isArchived }.count {
-                    db.cowspentServerSyncHelper.runAccountProjectsSync()
+                    val full = neverSynced(it)
-                }
+                    val scheduled = db.cowspentServerSyncHelper.scheduleSync(false, it, full) != null
-                remoteProjects.count {
+                    if (scheduled) {
-                    val scheduled = db.cowspentServerSyncHelper.scheduleSync(false, it, false) != null
+                        markProjectSynced(preferences, it.id, now)
-                    if (scheduled) markProjectSynced(preferences, it.id, now)
+                        if (full) markFullySynced(preferences, it.id, now)
+                    }
                     scheduled
                 }
             } else {
@@ -824,13 +862,11 @@ class BillsListViewActivity :
                 // the back gesture does to a large project, since it destroys the activity while
                 // the sync is still running. IHateMoney never advances the cursor, so the interval
                 // stays in charge there.
-                val neverCompleted = selectedProj != null &&
+                val neverCompleted = selectedProj != null && neverSynced(selectedProj)
-                    selectedProj.type != ProjectType.IHATEMONEY &&
-                    (selectedProj.lastSyncedTimestamp ?: 0L) == 0L
                 val due = trigger == SyncTrigger.MANUAL || neverCompleted ||
                     now - lastSync > SELECTED_PROJECT_SYNC_INTERVAL_MS
-                val fullSync = trigger == SyncTrigger.MANUAL &&
+                val fullSync = neverCompleted || (trigger == SyncTrigger.MANUAL &&
-                    !partialRefreshPreferred(preferences, selectedProjectId, now)
+                    !partialRefreshPreferred(preferences, selectedProjectId, now))
                 if (selectedProj != null && due &&
                     db.cowspentServerSyncHelper.scheduleSync(false, selectedProj, fullSync) != null
                 ) {
@@ -846,6 +882,24 @@ class BillsListViewActivity :
         }
     }
 
+    private fun neverSynced(project: DBProject) =
+        project.type != ProjectType.IHATEMONEY && (project.lastSyncedTimestamp ?: 0L) == 0L
+
+    @VisibleForTesting
+    internal fun syncNewlyDiscoveredProjects(projects: List<DBProject>) {
+        if (!db.cowspentServerSyncHelper.isSyncPossible) return
+        val preferences = PreferenceManager.getDefaultSharedPreferences(applicationContext)
+        val now = System.currentTimeMillis()
+        projects
+            .filter { !it.isLocal && !it.isArchived && neverSynced(it) }
+            .forEach {
+                if (db.cowspentServerSyncHelper.scheduleSync(false, it, true) != null) {
+                    markProjectSynced(preferences, it.id, now)
+                    markFullySynced(preferences, it.id, now)
+                }
+            }
+    }
+
     private fun lastProjectSyncKey(projectId: Long) = "lastProjectSyncTimestamp_$projectId"
     private fun lastFullSyncKey(projectId: Long) = "lastFullSyncTimestamp_$projectId"
 
@@ -948,6 +1002,7 @@ class BillsListViewActivity :
                                 synchronize(SyncTrigger.PROJECT_OPEN)
                             }
                         }
+                        syncNewlyDiscoveredProjects(dbProjects)
                     }
                 }
             }

app/src/main/java/net/helcel/cowspent/android/main/BillsListViewModel.kt

@@ -20,6 +20,7 @@ class BillsListViewModel : ViewModel() {
     var selectedMemberId by mutableStateOf<Long?>(null)
     var bills by mutableStateOf<List<Item>>(emptyList())
     var isRefreshing by mutableStateOf(false)
+    var isLoadingBills by mutableStateOf(false)
     var searchQuery by mutableStateOf("")
     var title by mutableStateOf("")
     var accountName by mutableStateOf("")

app/src/main/java/net/helcel/cowspent/android/project/ProjectOptionsDialog.kt

@@ -24,6 +24,7 @@ import net.helcel.cowspent.model.ProjectType
 fun ProjectOptionsDialogContent(
     onEditProject: () -> Unit,
     onRemoveProject: () -> Unit,
+    onForgetProject: () -> Unit = {},
     onManageMembers: () -> Unit,
     onManageCurrencies: () -> Unit,
     onManageLabels: () -> Unit,
@@ -73,6 +74,15 @@ fun ProjectOptionsDialogContent(
                 val archiveLabel = if (isArchived) stringResource(R.string.action_unarchive) else stringResource(R.string.action_archive)
                 val archiveIcon = if (isArchived) Icons.Default.Unarchive else Icons.Default.Archive
                 row1.add(ProjectOption(archiveLabel, archiveIcon, onRemoveProject))
+                if (isArchived) {
+                    row1.add(
+                        ProjectOption(
+                            stringResource(R.string.action_forget),
+                            Icons.Default.Delete,
+                            onForgetProject
+                        )
+                    )
+                }
             } else {
                 row1.add(ProjectOption(stringResource(R.string.action_delete), Icons.Default.Delete, onRemoveProject))
             }

app/src/main/java/net/helcel/cowspent/android/settings/PreferencesActivity.kt

@@ -5,6 +5,7 @@ import android.os.Bundle
 import androidx.activity.OnBackPressedCallback
 import androidx.activity.enableEdgeToEdge
 import androidx.activity.compose.setContent
+import androidx.activity.result.contract.ActivityResultContracts
 import androidx.appcompat.app.AppCompatActivity
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableIntStateOf
@@ -15,8 +16,13 @@ import androidx.compose.ui.platform.LocalContext
 import androidx.compose.ui.res.stringResource
 import androidx.core.app.NavUtils
 import androidx.preference.PreferenceManager
+import net.helcel.cowspent.R
 import net.helcel.cowspent.android.about.AboutActivity
 import net.helcel.cowspent.android.account.AccountActivity
+import net.helcel.cowspent.android.helper.showToast
+import net.helcel.cowspent.model.DBAccountProject
+import net.helcel.cowspent.persistence.CowspentSQLiteOpenHelper
+import net.helcel.cowspent.persistence.CowspentServerSyncHelper
 import net.helcel.cowspent.theme.ThemeUtils
 import net.helcel.cowspent.util.ColorUtils
 
@@ -25,6 +31,25 @@ import net.helcel.cowspent.util.ColorUtils
  */
 class PreferencesActivity : AppCompatActivity() {
 
+    private val accountLauncher = registerForActivityResult(
+        ActivityResultContracts.StartActivityForResult()
+    ) { result ->
+        if (result.resultCode == RESULT_OK) {
+            setResult(RESULT_OK, result.data)
+        }
+    }
+
+    private fun restoreDeletedProjects(projects: List<DBAccountProject>) {
+        if (projects.isEmpty()) return
+        val syncHelper = CowspentSQLiteOpenHelper.getInstance(applicationContext).cowspentServerSyncHelper
+        syncHelper.restoreAccountProjects(projects)
+        if (CowspentServerSyncHelper.isNextcloudAccountConfigured(applicationContext)) {
+            syncHelper.runAccountProjectsSync()
+        }
+        setResult(RESULT_OK)
+        showToast(this, getString(R.string.settings_restore_deleted_projects_done))
+    }
+
     override fun onCreate(savedInstanceState: Bundle?) {
         enableEdgeToEdge()
         super.onCreate(savedInstanceState)
@@ -59,13 +84,14 @@ class PreferencesActivity : AppCompatActivity() {
                 SettingsScreen(
                     onBack = { NavUtils.navigateUpFromSameTask(this) },
                     onAccountSettingsClick = {
-                        startActivity(Intent(this, AccountActivity::class.java))
+                        accountLauncher.launch(Intent(this, AccountActivity::class.java))
                     },
                     onAboutClick = {
                         startActivity(Intent(this, AboutActivity::class.java))
                     },
                     onColorSelected = { appColor = it },
-                    onNightModeChanged = { nightMode = it }
+                    onNightModeChanged = { nightMode = it },
+                    onRestoreDeletedProjects = { restoreDeletedProjects(it) }
                 )
             }
         }

app/src/main/java/net/helcel/cowspent/android/settings/SettingsScreen.kt

@@ -21,6 +21,7 @@ import androidx.compose.material.MaterialTheme
 import androidx.compose.material.RadioButton
 import androidx.compose.material.Scaffold
 import androidx.compose.material.Slider
+import androidx.compose.material.Checkbox
 import androidx.compose.material.Switch
 import androidx.compose.material.SwitchDefaults
 import androidx.compose.material.Text
@@ -34,11 +35,14 @@ import androidx.compose.material.icons.filled.Brightness2
 import androidx.compose.material.icons.filled.Group
 import androidx.compose.material.icons.filled.Info
 import androidx.compose.material.icons.filled.Palette
+import androidx.compose.material.icons.filled.Restore
 import androidx.compose.material.icons.filled.Sync
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.DisposableEffect
+import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableIntStateOf
+import androidx.compose.runtime.mutableStateListOf
 import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
 import androidx.compose.runtime.setValue
@@ -47,6 +51,7 @@ import androidx.compose.ui.Modifier
 import androidx.compose.ui.graphics.painter.Painter
 import androidx.compose.ui.graphics.vector.ImageVector
 import androidx.compose.ui.platform.LocalContext
+import androidx.compose.ui.res.pluralStringResource
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.tooling.preview.Preview
@@ -56,6 +61,9 @@ import androidx.core.content.edit
 import androidx.preference.PreferenceManager
 import net.helcel.cowspent.R
 import net.helcel.cowspent.android.helper.ColorPicker
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.withContext
+import net.helcel.cowspent.model.DBAccountProject
 import net.helcel.cowspent.persistence.CowspentSQLiteOpenHelper
 import net.helcel.cowspent.persistence.CowspentServerSyncHelper
 import net.helcel.cowspent.util.ColorUtils
@@ -68,7 +76,8 @@ fun SettingsScreen(
     onAccountSettingsClick: () -> Unit,
     onAboutClick: () -> Unit,
     onColorSelected: (Int) -> Unit,
-    onNightModeChanged: (String) -> Unit = {}
+    onNightModeChanged: (String) -> Unit = {},
+    onRestoreDeletedProjects: (List<DBAccountProject>) -> Unit = {}
 ) {
     val context = LocalContext.current
     val sharedPreferences = remember { PreferenceManager.getDefaultSharedPreferences(context) }
@@ -92,6 +101,16 @@ fun SettingsScreen(
 
     val isNextcloudConfigured = CowspentServerSyncHelper.isNextcloudAccountConfigured(context)
 
+    var deletedProjects by remember { mutableStateOf(emptyList<DBAccountProject>()) }
+    var showRestoreDialog by remember { mutableStateOf(false) }
+
+    // Off the main thread: this reads the account projects table.
+    LaunchedEffect(Unit) {
+        deletedProjects = withContext(Dispatchers.IO) {
+            CowspentSQLiteOpenHelper.getInstance(context).cowspentServerSyncHelper.deletedAccountProjects()
+        }
+    }
+
     // States for preferences
     var nightMode by remember(keyNightMode) {
         mutableStateOf(sharedPreferences.getString(keyNightMode, "-1") ?: "-1")
@@ -257,6 +276,32 @@ fun SettingsScreen(
                 onClick = onAccountSettingsClick
             )
 
+            // Nothing held back means nothing to undo, so the row is not offered at all.
+            if (deletedProjects.isNotEmpty()) {
+                SettingsPreference(
+                    title = stringResource(R.string.settings_restore_deleted_projects),
+                    summary = pluralStringResource(
+                        R.plurals.settings_restore_deleted_projects_summary,
+                        deletedProjects.size,
+                        deletedProjects.size
+                    ),
+                    icon = Icons.Default.Restore,
+                    onClick = { showRestoreDialog = true }
+                )
+            }
+
+            if (showRestoreDialog) {
+                RestoreDeletedProjectsDialog(
+                    projects = deletedProjects,
+                    onDismiss = { showRestoreDialog = false },
+                    onConfirm = { chosen ->
+                        showRestoreDialog = false
+                        onRestoreDeletedProjects(chosen)
+                        deletedProjects = deletedProjects - chosen.toSet()
+                    }
+                )
+            }
+
             // Other
             SettingsCategory(stringResource(R.string.settings_other))
 
@@ -349,6 +394,60 @@ fun SettingsScreen(
     }
 }
 
+@Composable
+fun RestoreDeletedProjectsDialog(
+    projects: List<DBAccountProject>,
+    onDismiss: () -> Unit,
+    onConfirm: (List<DBAccountProject>) -> Unit
+) {
+    val selected = remember(projects) { mutableStateListOf<DBAccountProject>().apply { addAll(projects) } }
+
+    AlertDialog(
+        onDismissRequest = onDismiss,
+        title = { Text(stringResource(R.string.settings_restore_deleted_projects)) },
+        text = {
+            Column(modifier = Modifier.verticalScroll(rememberScrollState())) {
+                projects.forEach { project ->
+                    val isSelected = project in selected
+                    Row(
+                        modifier = Modifier
+                            .fillMaxWidth()
+                            .selectable(
+                                selected = isSelected,
+                                onClick = {
+                                    if (isSelected) selected.remove(project) else selected.add(project)
+                                }
+                            )
+                            .padding(vertical = 8.dp),
+                        verticalAlignment = Alignment.CenterVertically
+                    ) {
+                        Checkbox(checked = isSelected, onCheckedChange = null)
+                        Spacer(Modifier.width(16.dp))
+                        Column {
+                            Text(
+                                text = project.name.ifEmpty { project.remoteId },
+                                style = MaterialTheme.typography.subtitle1
+                            )
+                            Text(text = project.ncUrl, style = MaterialTheme.typography.caption)
+                        }
+                    }
+                }
+            }
+        },
+        confirmButton = {
+            TextButton(
+                onClick = { onConfirm(selected.toList()) },
+                enabled = selected.isNotEmpty()
+            ) {
+                Text(stringResource(R.string.settings_restore_deleted_projects_confirm))
+            }
+        },
+        dismissButton = {
+            TextButton(onClick = onDismiss) { Text(stringResource(R.string.simple_cancel)) }
+        }
+    )
+}
+
 @Composable
 fun SettingsCategory(title: String) {
     Text(

app/src/main/java/net/helcel/cowspent/persistence/CowspentSQLiteOpenHelper.kt

@@ -4,6 +4,7 @@ import android.annotation.SuppressLint
 import android.content.ContentValues
 import android.content.Context
 import android.database.Cursor
+import android.database.DatabaseUtils
 import android.database.sqlite.SQLiteDatabase
 import android.database.sqlite.SQLiteOpenHelper
 import android.text.TextUtils
@@ -238,13 +239,7 @@ class CowspentSQLiteOpenHelper private constructor(val context: Context) :
 
     @WorkerThread
     private fun getProjectsCustom(selection: String, selectionArgs: Array<String>, orderBy: String?, db: SQLiteDatabase): List<DBProject> {
-        val cursor = db.query(table_projects, columnsProjects, selection, selectionArgs, null, null, orderBy)
+        return queryAll(db, table_projects, columnsProjects, selection, selectionArgs, orderBy, ::getProjectFromCursor)
-        val projects: MutableList<DBProject> = ArrayList()
-        while (cursor.moveToNext()) {
-            projects.add(getProjectFromCursor(cursor))
-        }
-        cursor.close()
-        return projects
     }
 
     @SuppressLint("Range")
@@ -305,11 +300,17 @@ class CowspentSQLiteOpenHelper private constructor(val context: Context) :
 
     fun deleteProject(id: Long) {
         val db = writableDatabase
-        for (b in getBillsOfProject(id)) {
+        val projectId = arrayOf(id.toString())
-            deleteBill(b.id)
+        inTransaction {
+            db.delete(
+                table_billowers,
+                "$key_billId IN (SELECT $key_id FROM $table_bills WHERE $key_projectid = ?)",
+                projectId
+            )
+            db.delete(table_bills, "$key_projectid = ?", projectId)
+            db.delete(table_members, "$key_projectid = ?", projectId)
+            db.delete(table_projects, "$key_id = ?", projectId)
         }
-        db.delete(table_members, "$key_projectid = ?", arrayOf(id.toString()))
-        db.delete(table_projects, "$key_id = ?", arrayOf(id.toString()))
         SecureStorage.removePasswordSync(context, "ProjectPassword_$id")
     }
 
@@ -413,14 +414,7 @@ class CowspentSQLiteOpenHelper private constructor(val context: Context) :
 
     @WorkerThread
     private fun getMembersCustom(selection: String, selectionArgs: Array<String>, orderBy: String?): List<DBMember> {
-        val db = readableDatabase
+        return queryAll(readableDatabase, table_members, columnsMembers, selection, selectionArgs, orderBy, ::getMemberFromCursor)
-        val cursor = db.query(table_members, columnsMembers, selection, selectionArgs, null, null, orderBy)
-        val members: MutableList<DBMember> = ArrayList()
-        while (cursor.moveToNext()) {
-            members.add(getMemberFromCursor(cursor))
-        }
-        cursor.close()
-        return members
     }
 
     @SuppressLint("Range")
@@ -561,6 +555,14 @@ class CowspentSQLiteOpenHelper private constructor(val context: Context) :
         return getBillsCustom("$key_projectid = ?", arrayOf(projId.toString()), "$key_timestamp ASC")
     }
     
+    @WorkerThread
+    fun countUnsyncedBills(projId: Long): Int = DatabaseUtils.queryNumEntries(
+        readableDatabase,
+        table_bills,
+        "$key_projectid = ? AND $key_state != ?",
+        arrayOf(projId.toString(), DBBill.STATE_OK.toString())
+    ).toInt()
+
     fun getBillsOfProjectWithState(projId: Long, state: Int): List<DBBill> {
         return getBillsCustom(
             "$key_projectid = ? AND $key_state = ?",
@@ -644,29 +646,20 @@ class CowspentSQLiteOpenHelper private constructor(val context: Context) :
     @WorkerThread
     private fun getBillsCustom(selection: String, selectionArgs: Array<String>, orderBy: String?): List<DBBill> {
         val db = readableDatabase
-        val cursor = db.query(table_bills, columnsBills, selection, selectionArgs, null, null, orderBy)
+        return db.transactionally {
-        val bills: MutableList<DBBill> = ArrayList()
+            val bills = queryAll(db, table_bills, columnsBills, selection, selectionArgs, orderBy, ::getBillFromCursor)
-        while (cursor.moveToNext()) {
+            if (bills.isNotEmpty()) {
-            bills.add(getBillFromCursor(cursor))
+                val owersByBill = queryAll(
+                    db, table_billowers, columnsBillowers,
+                    "$key_billId IN (SELECT $key_id FROM $table_bills WHERE $selection)",
+                    selectionArgs, null, ::getBillOwerFromCursor
+                ).groupBy { it.billId }
+                for (bill in bills) {
+                    bill.billOwers = owersByBill[bill.id].orEmpty()
+                }
+            }
+            bills
         }
-        cursor.close()
-        if (bills.isEmpty()) return bills
-
-        // Every ower of the matched bills in one query, keyed back to its bill.
-        //
-        // Fetching them per bill meant a project with thousands of bills issued thousands of
-        // queries on every list refresh - and that refresh runs on resume, on switching project,
-        // and after each sync. The bill ids are re-selected as a subquery rather than bound as
-        // arguments, which would blow past SQLite's limit on bound variables for a large project.
-        val owersByBill = getBillOwersCustom(
-            "$key_billId IN (SELECT $key_id FROM $table_bills WHERE $selection)",
-            selectionArgs,
-            null
-        ).groupBy { it.billId }
-        for (bill in bills) {
-            bill.billOwers = owersByBill[bill.id].orEmpty()
-        }
-        return bills
     }
 
     @SuppressLint("Range")
@@ -714,14 +707,7 @@ class CowspentSQLiteOpenHelper private constructor(val context: Context) :
 
     @WorkerThread
     private fun getBillOwersCustom(selection: String, selectionArgs: Array<String>, orderBy: String?): List<DBBillOwer> {
-        val db = readableDatabase
+        return queryAll(readableDatabase, table_billowers, columnsBillowers, selection, selectionArgs, orderBy, ::getBillOwerFromCursor)
-        val cursor = db.query(table_billowers, columnsBillowers, selection, selectionArgs, null, null, orderBy)
-        val billOwers: MutableList<DBBillOwer> = ArrayList()
-        while (cursor.moveToNext()) {
-            billOwers.add(getBillOwerFromCursor(cursor))
-        }
-        cursor.close()
-        return billOwers
     }
 
     @SuppressLint("Range")
@@ -788,14 +774,7 @@ class CowspentSQLiteOpenHelper private constructor(val context: Context) :
 
     @WorkerThread
     private fun getCategoriesCustom(selection: String, selectionArgs: Array<String>, orderBy: String?): List<DBCategory> {
-        val db = readableDatabase
+        return queryAll(readableDatabase, table_categories, columnsCategories, selection, selectionArgs, orderBy, ::getCategoryFromCursor)
-        val cursor = db.query(table_categories, columnsCategories, selection, selectionArgs, null, null, orderBy)
-        val categories: MutableList<DBCategory> = ArrayList()
-        while (cursor.moveToNext()) {
-            categories.add(getCategoryFromCursor(cursor))
-        }
-        cursor.close()
-        return categories
     }
 
     @SuppressLint("Range")
@@ -904,13 +883,7 @@ class CowspentSQLiteOpenHelper private constructor(val context: Context) :
 
     @WorkerThread
     private fun getPaymentModesCustom(selection: String, selectionArgs: Array<String>, orderBy: String?, db: SQLiteDatabase): List<DBPaymentMode> {
-        val cursor = db.query(table_payment_modes, columnsPaymentModes, selection, selectionArgs, null, null, orderBy)
+        return queryAll(db, table_payment_modes, columnsPaymentModes, selection, selectionArgs, orderBy, ::getPaymentModeFromCursor)
-        val paymentModes: MutableList<DBPaymentMode> = ArrayList()
-        while (cursor.moveToNext()) {
-            paymentModes.add(getPaymentModeFromCursor(cursor))
-        }
-        cursor.close()
-        return paymentModes
     }
 
     @SuppressLint("Range")
@@ -1020,13 +993,7 @@ class CowspentSQLiteOpenHelper private constructor(val context: Context) :
 
     @WorkerThread
     private fun getCurrenciesCustom(selection: String, selectionArgs: Array<String>, orderBy: String?, db: SQLiteDatabase): List<DBCurrency> {
-        val cursor = db.query(table_currencies, columnsCurrencies, selection, selectionArgs, null, null, orderBy)
+        return queryAll(db, table_currencies, columnsCurrencies, selection, selectionArgs, orderBy, ::getCurrencyFromCursor)
-        val currencies: MutableList<DBCurrency> = ArrayList()
-        while (cursor.moveToNext()) {
-            currencies.add(getCurrencyFromCursor(cursor))
-        }
-        cursor.close()
-        return currencies
     }
 
     @SuppressLint("Range")
@@ -1074,6 +1041,36 @@ class CowspentSQLiteOpenHelper private constructor(val context: Context) :
 
     // --- Common Helpers ---
 
+    @WorkerThread
+    private fun <T> queryAll(
+        db: SQLiteDatabase,
+        table: String,
+        columns: Array<String>,
+        selection: String?,
+        selectionArgs: Array<String>?,
+        orderBy: String?,
+        fromCursor: (Cursor) -> T
+    ): List<T> = db.transactionally {
+        val items: MutableList<T> = ArrayList()
+        db.query(table, columns, selection, selectionArgs, null, null, orderBy).use { cursor ->
+            while (cursor.moveToNext()) {
+                items.add(fromCursor(cursor))
+            }
+        }
+        items
+    }
+
+    private fun <T> SQLiteDatabase.transactionally(block: () -> T): T {
+        beginTransaction()
+        try {
+            val result = block()
+            setTransactionSuccessful()
+            return result
+        } finally {
+            endTransaction()
+        }
+    }
+
     fun syncIfRemote(proj: DBProject) {
         if (!proj.isLocal) {
             val preferences = PreferenceManager.getDefaultSharedPreferences(context)
@@ -1146,13 +1143,7 @@ class CowspentSQLiteOpenHelper private constructor(val context: Context) :
 
     @WorkerThread
     private fun getAccountProjectsCustom(selection: String, selectionArgs: Array<String>, orderBy: String?, db: SQLiteDatabase): List<DBAccountProject> {
-        val cursor = db.query(table_account_projects, columnsAccountProjects, selection, selectionArgs, null, null, orderBy)
+        return queryAll(db, table_account_projects, columnsAccountProjects, selection, selectionArgs, orderBy, ::getAccountProjectFromCursor)
-        val accountProjects: MutableList<DBAccountProject> = ArrayList()
-        while (cursor.moveToNext()) {
-            accountProjects.add(getAccountProjectFromCursor(cursor))
-        }
-        cursor.close()
-        return accountProjects
     }
 
     @SuppressLint("Range")

app/src/main/java/net/helcel/cowspent/persistence/CowspentServerSyncHelper.kt

@@ -6,6 +6,7 @@ import android.content.SharedPreferences
 import android.net.ConnectivityManager
 import android.util.Log
 import androidx.annotation.VisibleForTesting
+import androidx.annotation.WorkerThread
 import androidx.core.content.edit
 import androidx.core.graphics.toColorInt
 import androidx.preference.PreferenceManager
@@ -14,6 +15,7 @@ import com.nextcloud.android.sso.api.NextcloudAPI
 import com.nextcloud.android.sso.exceptions.NextcloudHttpRequestFailedException
 import com.nextcloud.android.sso.exceptions.TokenMismatchException
 import com.nextcloud.android.sso.helper.SingleAccountHelper
+import kotlinx.coroutines.CancellationException
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Deferred
 import kotlinx.coroutines.Dispatchers
@@ -26,6 +28,7 @@ import net.helcel.cowspent.R
 import net.helcel.cowspent.android.account.AccountActivity
 import net.helcel.cowspent.android.main.BillsListViewActivity
 import net.helcel.cowspent.android.main.MainConstants
+import net.helcel.cowspent.model.DBAccountProject
 import net.helcel.cowspent.model.DBBill
 import net.helcel.cowspent.model.DBMember
 import net.helcel.cowspent.model.DBProject
@@ -176,14 +179,22 @@ class CowspentServerSyncHelper private constructor(private val dbHelper: Cowspen
         }
 
         fun execute(): SyncTask {
+            syncActive = true
             deferred = scope.async {
-                syncActive = true
+                try {
-                val status = withContext(Dispatchers.IO) {
+                    val status = withContext(Dispatchers.IO) {
-                    doWork()
+                        doWork()
+                    }
+                    onPostExecute(status)
+                    status
+                } catch (e: CancellationException) {
+                    syncActive = false
+                    throw e
+                } catch (e: Exception) {
+                    Log.e(TAG, "Sync failed for ${project.remoteId}", e)
+                    syncActive = false
+                    LoginStatus.CONNECTION_FAILED
                 }
-                onPostExecute(status)
-                syncActive = false
-                status
             }
             return this
         }
@@ -293,12 +304,8 @@ class CowspentServerSyncHelper private constructor(private val dbHelper: Cowspen
                                 null, null, null, null, null
                             )
                         }
-                    } catch (e: IOException) {
+                    } catch (e: Exception) {
-                        if (e.message == "{\"message\": \"Internal Server Error\"}") {
+                        Log.e(TAG, "EDIT MEMBER FAILED for ${mToEdit.name}", e)
-                            Log.d(TAG, "EDIT MEMBER FAILED : it does not exist remotely")
-                        } else {
-                            throw e
-                        }
                     }
                 }
 
@@ -1048,6 +1055,8 @@ class CowspentServerSyncHelper private constructor(private val dbHelper: Cowspen
             for (localMember in dbHelper.getMembersOfProject(project.id, null)) {
                 if (remoteMembersByRemoteId.containsKey(localMember.remoteId)) continue
 
+                if (localMember.state != DBBill.STATE_OK) continue
+
                 // A member still named by a bill cannot be removed without orphaning it.
                 if (dbHelper.getBillsOfMember(localMember.id).isEmpty() &&
                     dbHelper.getBillowersOfMember(localMember.id).isEmpty()
@@ -1468,6 +1477,21 @@ class CowspentServerSyncHelper private constructor(private val dbHelper: Cowspen
         }
     }
 
+    @WorkerThread
+    fun deletedAccountProjects(): List<DBAccountProject> {
+        val forgotten = forgottenAccountProjects(preferences)
+        if (forgotten.isEmpty()) return emptyList()
+        return dbHelper.accountProjects.filter { accountProjectKey(it.remoteId, it.ncUrl) in forgotten }
+    }
+
+    fun restoreAccountProjects(projects: List<DBAccountProject>) {
+        if (projects.isEmpty()) return
+        val restored = projects.map { accountProjectKey(it.remoteId, it.ncUrl) }.toSet()
+        preferences.edit {
+            putStringSet(FORGOTTEN_ACCOUNT_PROJECTS, forgottenAccountProjects(preferences) - restored)
+        }
+    }
+
     fun runAccountProjectsSync() {
         Log.d(TAG, "Account projects sync requested; ${if (syncAccountProjectsActive) "sync active" else "sync NOT active"}) ...")
         updateNetworkStatus()
@@ -1514,11 +1538,18 @@ class CowspentServerSyncHelper private constructor(private val dbHelper: Cowspen
         fun execute(): SyncAccountProjectsTask {
             scope.launch {
                 syncAccountProjectsActive = true
-                val status = withContext(Dispatchers.IO) {
+                try {
-                    doWork()
+                    val status = withContext(Dispatchers.IO) {
+                        doWork()
+                    }
+                    onPostExecute(status)
+                } catch (e: CancellationException) {
+                    throw e
+                } catch (e: Exception) {
+                   Log.e(TAG, "Account projects sync failed", e)
+                } finally {
+                    syncAccountProjectsActive = false
                 }
-                onPostExecute(status)
-                syncAccountProjectsActive = false
             }
             return this
         }
@@ -1547,20 +1578,25 @@ class CowspentServerSyncHelper private constructor(private val dbHelper: Cowspen
                 
                 val response = client.getAccountProjects(useOcsApi)
                 val remoteAccountProjects = response.getAccountProjects(url)
+                val forgotten = forgottenAccountProjects(preferences)
                 dbHelper.clearAccountProjects()
                 for (remoteAccountProject in remoteAccountProjects) {
                     dbHelper.addAccountProject(remoteAccountProject)
                     Log.v(TAG, "received account project $remoteAccountProject")
                     val existingProj = localProjects.find {
                         it.remoteId == remoteAccountProject.remoteId &&
-                        it.serverUrl?.replace("/+$".toRegex(), "") == remoteAccountProject.ncUrl.replace("/+$".toRegex(), "") + "/index.php/apps/cospend"
+                        it.serverUrl?.replace("/+$".toRegex(), "") == remoteAccountProject.ncUrl.replace("/+$".toRegex(), "") + COSPEND_PATH
                     }
                     if (existingProj == null) {
+                        if (accountProjectKey(remoteAccountProject.remoteId, remoteAccountProject.ncUrl) in forgotten) {
+                            Log.d(TAG, "skipping ${remoteAccountProject.remoteId}, deleted on this device")
+                            continue
+                        }
                         val newProj = DBProject(0,
                             remoteAccountProject.remoteId,
                             "",
                             remoteAccountProject.name,
-                            remoteAccountProject.ncUrl.replace("/+$".toRegex(), "") + "/index.php/apps/cospend",
+                            remoteAccountProject.ncUrl.replace("/+$".toRegex(), "") + COSPEND_PATH,
                             "",
                             null,
                             ProjectType.COSPEND,
@@ -1896,6 +1932,34 @@ class CowspentServerSyncHelper private constructor(private val dbHelper: Cowspen
                     preferences.getBoolean(AccountActivity.SETTINGS_USE_SSO, false)
         }
 
+        /** The path a Cospend project's URL carries on top of its Nextcloud server URL. */
+        const val COSPEND_PATH = "/index.php/apps/cospend"
+
+        private const val FORGOTTEN_ACCOUNT_PROJECTS = "forgottenAccountProjects"
+
+        private fun trimSlashes(url: String) = url.replace("/+$".toRegex(), "")
+
+        /** Names one project an account offers, by server and remote id, with no local row needed. */
+        private fun accountProjectKey(remoteId: String, ncUrl: String) = "${trimSlashes(ncUrl)}|$remoteId"
+
+        /** The same key for a stored project, or null when it is not one an account can offer. */
+        private fun accountProjectKey(project: DBProject): String? {
+            val url = trimSlashes(project.serverUrl.orEmpty())
+            if (!url.endsWith(COSPEND_PATH)) return null
+            return accountProjectKey(project.remoteId, url.removeSuffix(COSPEND_PATH))
+        }
+
+        private fun forgottenAccountProjects(preferences: SharedPreferences): Set<String> =
+            preferences.getStringSet(FORGOTTEN_ACCOUNT_PROJECTS, emptySet()).orEmpty()
+        
+        fun forgetAccountProject(context: Context, project: DBProject) {
+            val key = accountProjectKey(project) ?: return
+            val preferences = PreferenceManager.getDefaultSharedPreferences(context)
+            preferences.edit {
+                putStringSet(FORGOTTEN_ACCOUNT_PROJECTS, forgottenAccountProjects(preferences) + key)
+            }
+        }
+
         fun getNextcloudAccountServerUrl(context: Context): String {
             val preferences = PreferenceManager.getDefaultSharedPreferences(context)
             return if (preferences.getBoolean(AccountActivity.SETTINGS_USE_SSO, false)) {

app/src/main/res/values/strings.xml

@@ -17,6 +17,7 @@
     <string name="simple_back">Back</string>
     <string name="action_archive">Archive</string>
     <string name="action_unarchive">Unarchive</string>
+    <string name="action_forget">Delete locally</string>
     <string name="action_export">Export</string>
     <string name="action_stats">Stats</string>
     <string name="action_settle">Settle</string>
@@ -24,6 +25,8 @@
     <string name="action_settings">Settings</string>
     <string name="action_label_bills">Label missing categories</string>
     <string name="action_logout">Logout</string>
+    <string name="logout_confirm_title">Log out?</string>
+    <string name="logout_confirm_no_projects">You can sign back in at any time.</string>
     <string name="action_connect">Connect</string>
     <string name="action_discard">Discard</string>
     <string name="action_members">Members</string>
@@ -136,6 +139,9 @@
     <string name="settings_night_mode">Theme</string>
     <string name="settings_offline_mode">Offline mode</string>
     <string name="settings_offline_mode_summary">Only sync manually.</string>
+    <string name="settings_restore_deleted_projects">Restore deleted projects</string>
+    <string name="settings_restore_deleted_projects_done">Restoring from the account</string>
+    <string name="settings_restore_deleted_projects_confirm">Restore</string>
     <string name="settings_color_custom">Custom color</string>
     <string name="settings_color_mode">Color Selection</string>
     <string name="settings_show_archived">Show archived projects</string>
@@ -290,4 +296,19 @@
     <string name="share_intent_title">Project %1$s</string>
     <string name="share_chooser_title">Share %1$s</string>
 
+
+    <plurals name="settings_restore_deleted_projects_summary">
+        <item quantity="one">%d project the account offers is kept off this device.</item>
+        <item quantity="other">%d projects the account offers are kept off this device.</item>
+    </plurals>
+
+    <plurals name="logout_confirm_projects">
+        <item quantity="one">%d project from this account will be removed from this device. It comes back when you sign in again.</item>
+        <item quantity="other">%d projects from this account will be removed from this device. They come back when you sign in again.</item>
+    </plurals>
+
+    <plurals name="warning_unsynced_bills">
+        <item quantity="one">%d bill has not reached the server yet and will be lost.</item>
+        <item quantity="other">%d bills have not reached the server yet and will be lost.</item>
+    </plurals>
 </resources>