fix(mobile): let the host's transcript and catalog be the single mobile authority

src/apps/mobile/android/app/src/androidTest/kotlin/com/openbitfun/mobile/app/ConversationViewTest.kt

@@ -354,6 +354,17 @@ class ConversationViewTest {
         )
     }
 
+    @Test
+    fun composerRemainsEditableWhileNewSessionHydrates() {
+        val intents = mutableListOf<RemoteSessionIntent>()
+        val state = mutableStateOf(readyState(sessionId = "pending", draft = "").copy(busy = true, timeline = null))
+
+        setConversationContent(state = { state.value }, onIntent = { intents += it })
+
+        composeRule.onNodeWithTag(COMPOSER_INPUT_TEST_TAG).performTextReplacement("draft during load")
+        assertEquals(listOf(RemoteSessionIntent.UpdateDraft("draft during load")), intents)
+    }
+
     @Test
     fun composerFollowsStoreDraftUpdatesWithinTheSameSession() {
         val state = mutableStateOf(readyState(sessionId = "s-code", draft = "first"))
@@ -403,6 +414,37 @@ class ConversationViewTest {
         composeRule.onNodeWithTag(COMPOSER_INPUT_TEST_TAG).assertTextEquals("send me")
     }
 
+    @Test
+    fun submittedDraftStaysClearedAcrossRecreationWhileAwaitingAck() {
+        val restoration = androidx.compose.ui.test.junit4.StateRestorationTester(composeRule)
+        val state = mutableStateOf(readyState(sessionId = "s-code", draft = "send me"))
+        restoration.setContent {
+            OpenBitFunTheme(dark = false) {
+                ConversationView(
+                    state = state.value, phase = ConnectionPhase.CONNECTED,
+                    settingsPlacement = SettingsPlacement(SettingsPlacementMode.BOTTOM, 0, 0, 0),
+                    onBack = {}, onIntent = { intent ->
+                        state.value = when (intent) {
+                            is RemoteSessionIntent.UpdateDraft -> state.value.copy(draft = intent.text)
+                            else -> state.value.copy(busy = true)
+                        }
+                    }, contextTitle = "Test desktop", onOpenFile = { _, _ -> },
+                    previewingRemotePath = "", previewLoading = false,
+                    download = RemoteFileDownloadUiState.None, onDownloadFile = { _, _ -> },
+                    modifier = Modifier.fillMaxSize(),
+                )
+            }
+        }
+        composeRule.onNodeWithTag(COMPOSER_SEND_TEST_TAG).performClick()
+        restoration.emulateSavedInstanceStateRestore()
+        composeRule.onNodeWithTag(COMPOSER_INPUT_TEST_TAG).assert(
+            SemanticsMatcher.expectValue(SemanticsProperties.EditableText, AnnotatedString("")),
+        )
+        composeRule.onNodeWithTag(COMPOSER_INPUT_TEST_TAG).performTextReplacement("next draft")
+        composeRule.runOnIdle { state.value = state.value.copy(busy = false) }
+        composeRule.onNodeWithTag(COMPOSER_INPUT_TEST_TAG).assertTextEquals("next draft")
+    }
+
     @Test
     fun emptyStateShowsInvitationCopy() {
         composeRule.setContent {

src/apps/mobile/android/app/src/main/kotlin/com/openbitfun/mobile/app/ui/chat/ComposerBar.kt

@@ -125,6 +125,8 @@ internal fun ComposerBar(
     draft: String,
     images: List<ComposerImage>,
     busy: Boolean,
+    /** The draft may be edited while a newly opened session is hydrating. */
+    inputEnabled: Boolean = !busy,
     streaming: Boolean,
     phase: ConnectionPhase,
     model: ModelOption?,
@@ -273,7 +275,7 @@ internal fun ComposerBar(
                     }
                     ComposerField(
                         draft = draft,
-                        enabled = !busy,
+                        enabled = inputEnabled,
                         expanded = expanded,
                         placeholder = placeholder,
                         onDraftChange = onDraftChange,
@@ -290,6 +292,7 @@ internal fun ComposerBar(
                         }
                         PrimaryActionButton(
                             action = action,
+                            stopEnabled = ChatComposerPolicy.canStop(streaming, capabilities.requiresRemoteConnection, phase),
                             onVoice = onVoice,
                             onSend = onSend,
                             onStop = onStop,
@@ -669,13 +672,14 @@ private const val DimmedAlpha: Float = 0.38f
 @Composable
 private fun PrimaryActionButton(
     action: ComposerPrimaryAction,
+    stopEnabled: Boolean = true,
     onVoice: () -> Unit,
     onSend: () -> Unit,
     onStop: () -> Unit,
     testTag: String = COMPOSER_SEND_TEST_TAG,
 ) {
     val colors = MaterialTheme.colorScheme
-    val enabled = action == ComposerPrimaryAction.STOP ||
+    val enabled = (action == ComposerPrimaryAction.STOP && stopEnabled) ||
         action == ComposerPrimaryAction.SEND ||
         action == ComposerPrimaryAction.VOICE
     val description = when (action) {

src/apps/mobile/android/app/src/main/kotlin/com/openbitfun/mobile/app/ui/chat/ConversationTimelineView.kt

@@ -4,17 +4,23 @@ import com.openbitfun.mobile.core.feature.session.HistoryLoadState
 
 import androidx.compose.foundation.layout.Arrangement
 import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.PaddingValues
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.Spacer
 import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.offset
+import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.layout.width
 import androidx.compose.foundation.interaction.DragInteraction
 import androidx.compose.foundation.lazy.LazyColumn
 import androidx.compose.foundation.lazy.items
 import androidx.compose.foundation.lazy.rememberLazyListState
 import androidx.compose.foundation.shape.CircleShape
 import androidx.compose.material3.ButtonDefaults
+import androidx.compose.material3.CircularProgressIndicator
 import androidx.compose.material3.Icon
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.Surface
@@ -59,12 +65,13 @@ internal object ConversationScrollPolicy {
         stickToBottom && hasRows
 
     /**
-     * The LazyColumn puts the "load older messages" header at index zero when
-     * [hasMoreMessages] is true, so the real tail is one past [rowCount] instead
-     * of `rowCount - 1`.
+     * The LazyColumn puts one leading header in front of the messages when the
+     * transcript has an older page to load or has not been confirmed by the
+     * host yet, so the real tail is one past [rowCount] instead of
+     * `rowCount - 1`.
      */
-    fun lastItemIndex(rowCount: Int, hasMoreMessages: Boolean): Int =
-        if (hasMoreMessages) rowCount else (rowCount - 1).coerceAtLeast(0)
+    fun lastItemIndex(rowCount: Int, hasLeadingItem: Boolean): Int =
+        if (hasLeadingItem) rowCount else (rowCount - 1).coerceAtLeast(0)
 }
 
 /** One automatic page per deliberate drag; layout and bounce cannot re-arm it. */
@@ -84,6 +91,12 @@ internal class HistoryPageArrivalTracker {
 internal fun ConversationTimelineView(
     rows: List<ConversationRow>,
     hasMoreMessages: Boolean,
+    /**
+     * The rows on screen are this device's stored copy rather than the host's
+     * transcript: a reopened session shows them at once, and the host has not
+     * answered for it yet. See `ChatTranscriptOrigin`.
+     */
+    transcriptUnconfirmed: Boolean = false,
     onLoadOlder: () -> Unit,
     enabled: Boolean,
     onApproveTool: (String, String?) -> Unit,
@@ -111,6 +124,9 @@ internal fun ConversationTimelineView(
     val listState = rememberLazyListState()
     var stickToBottom by rememberSaveable { mutableStateOf(true) }
     val atBottom by remember(listState) { derivedStateOf { !listState.canScrollForward } }
+    // One header slot holds both leading rows, so the scroll policy counts an
+    // item, not a row.
+    val hasLeadingItem = hasMoreMessages || transcriptUnconfirmed
 
     val historyArrival = remember { HistoryPageArrivalTracker() }
     var userDragging by remember { mutableStateOf(false) }
@@ -132,12 +148,12 @@ internal fun ConversationTimelineView(
                 )
             }
     }
-    LaunchedEffect(rows, stickToBottom, hasMoreMessages) {
+    LaunchedEffect(rows, stickToBottom, hasLeadingItem) {
         if (ConversationScrollPolicy.shouldScrollToBottom(stickToBottom, rows.isNotEmpty())) {
             // A large offset positions the item's bottom at the viewport tail directly;
             // unlike scrollToItem(index), it does not briefly expose the item's top.
             listState.scrollToItem(
-                ConversationScrollPolicy.lastItemIndex(rows.size, hasMoreMessages),
+                ConversationScrollPolicy.lastItemIndex(rows.size, hasLeadingItem),
                 scrollOffset = Int.MAX_VALUE,
             )
         }
@@ -180,19 +196,46 @@ internal fun ConversationTimelineView(
             ),
             verticalArrangement = Arrangement.spacedBy(12.dp, Alignment.Bottom),
         ) {
-            if (hasMoreMessages) {
+            if (hasLeadingItem) {
                 item(key = "load-older-messages") {
-                    Box(modifier = Modifier.fillMaxWidth(), contentAlignment = Alignment.Center) {
-                        TextButton(
-                            onClick = { historyArrival.cancelArrival(); stickToBottom = false; onLoadOlder() },
-                            enabled = enabled && historyLoadState != HistoryLoadState.LOADING,
-                            colors = ButtonDefaults.textButtonColors(contentColor = MaterialTheme.colorScheme.onSurfaceVariant),
-                        ) {
-                            Text(stringResource(when (historyLoadState) {
-                                HistoryLoadState.LOADING -> R.string.chat_loading_older_messages
-                                HistoryLoadState.FAILED -> R.string.chat_load_older_failed
-                                else -> R.string.chat_load_older_messages
-                            }))
+                    Column(modifier = Modifier.fillMaxWidth()) {
+                        if (transcriptUnconfirmed) {
+                            // These rows stop where this device's last write stopped,
+                            // inside the turn that was running when the app went away.
+                            // Say the rest is on its way instead of letting a
+                            // half-finished turn read as the session.
+                            Row(
+                                modifier = Modifier.fillMaxWidth().padding(vertical = 8.dp),
+                                horizontalArrangement = Arrangement.Center,
+                                verticalAlignment = Alignment.CenterVertically,
+                            ) {
+                                CircularProgressIndicator(
+                                    modifier = Modifier.size(16.dp),
+                                    strokeWidth = 2.dp,
+                                    color = MaterialTheme.colorScheme.onSurfaceVariant,
+                                )
+                                Spacer(modifier = Modifier.width(7.dp))
+                                Text(
+                                    text = stringResource(R.string.chat_transcript_syncing),
+                                    style = MaterialTheme.typography.labelMedium,
+                                    color = MaterialTheme.colorScheme.onSurfaceVariant,
+                                )
+                            }
+                        }
+                        if (hasMoreMessages) {
+                            Box(modifier = Modifier.fillMaxWidth(), contentAlignment = Alignment.Center) {
+                                TextButton(
+                                    onClick = { historyArrival.cancelArrival(); stickToBottom = false; onLoadOlder() },
+                                    enabled = enabled && historyLoadState != HistoryLoadState.LOADING,
+                                    colors = ButtonDefaults.textButtonColors(contentColor = MaterialTheme.colorScheme.onSurfaceVariant),
+                                ) {
+                                    Text(stringResource(when (historyLoadState) {
+                                        HistoryLoadState.LOADING -> R.string.chat_loading_older_messages
+                                        HistoryLoadState.FAILED -> R.string.chat_load_older_failed
+                                        else -> R.string.chat_load_older_messages
+                                    }))
+                                }
+                            }
                         }
                     }
                 }

src/apps/mobile/android/app/src/main/kotlin/com/openbitfun/mobile/app/ui/chat/ConversationView.kt

@@ -79,6 +79,7 @@ import com.openbitfun.mobile.core.feature.session.RemoteSessionUiState
 import com.openbitfun.mobile.core.feature.session.conversationRows
 import com.openbitfun.mobile.core.feature.session.modelOptions
 import com.openbitfun.mobile.core.feature.session.selectedModelOption
+import com.openbitfun.mobile.core.feature.session.transcriptUnconfirmed
 import com.openbitfun.mobile.core.feature.workspace.RemoteFileDownloadUiState
 
 internal const val CONVERSATION_TEST_TAG: String = "conversation"
@@ -182,7 +183,7 @@ internal fun ConversationView(
     // The remote composer's single source of truth is the store's draft. Typing,
     // voice, and send all round-trip through `state.draft` so a half-written
     // message survives session switches and process restarts via DraftStore.
-    var submittedDraft by remember(attachmentOwner, state.selectedSessionId) { mutableStateOf<String?>(null) }
+    var submittedDraft by rememberSaveable(attachmentOwner, state.selectedSessionId) { mutableStateOf<String?>(null) }
     val draft = if (submittedDraft == state.draft) "" else state.draft
     val focusManager = LocalFocusManager.current
     val keyboard = LocalSoftwareKeyboardController.current
@@ -304,7 +305,7 @@ internal fun ConversationView(
             ConversationHeader(
                 title = state.sessions.firstOrNull { it.id == sessionId }?.title.orEmpty(),
                 contextTitle = contextTitle,
-                canStop = activeTurn != null,
+                canStop = activeTurn != null && phase == ConnectionPhase.CONNECTED,
                 enabled = !state.busy && sessionId.isNotEmpty(),
                 onBack = onBack,
                 onOpenSidebar = onOpenSidebar,
@@ -347,6 +348,11 @@ internal fun ConversationView(
                     images = images,
                     // An empty session id would send nowhere, so it reads as busy.
                     busy = state.busy || preparingImage || attachmentsBlocked || sessionId.isEmpty(),
+                    // Session hydration must not make the draft field require
+                    // repeated taps. Sending and attachment actions remain
+                    // guarded by `busy`; typing can start as soon as a session
+                    // has been selected and the draft survives hydration.
+                    inputEnabled = sessionId.isNotEmpty() && !preparingImage && !attachmentsBlocked,
                     streaming = activeTurn != null,
                     phase = phase,
                     model = timeline?.selectedModelOption(stringResource(R.string.models_unnamed)),
@@ -444,6 +450,9 @@ private fun ConversationTimelineViewHost(
     ConversationTimelineView(
         rows = visibleRows,
         hasMoreMessages = state.hasMoreMessages,
+        transcriptUnconfirmed = state.timeline
+            ?.takeIf { it.sessionId == state.selectedSessionId }
+            ?.transcriptUnconfirmed() == true,
         historyLoadState = state.historyLoadState,
         onLoadOlder = { onIntent(RemoteSessionIntent.LoadOlderMessages) },
         enabled = !state.busy,

src/apps/mobile/android/app/src/main/kotlin/com/openbitfun/mobile/app/ui/remote/PairingScreen.kt

@@ -266,7 +266,7 @@ internal fun RemoteCompactHome(
                 ) { Text(stringResource(R.string.home_recent_all), fontSize = 12.sp) }
             }
             recent.forEach { session ->
-                Column(Modifier.fillMaxWidth().clickable(enabled = !ready!!.busy) { onOpen(session.id) }
+                Column(Modifier.fillMaxWidth().clickable { onOpen(session.id) }
                     .padding(vertical = MobileDesignGeometry.RecentHomeRowPadding)) {
                     Text(session.title, fontSize = 15.sp, maxLines = 2)
                     val workspace = session.workspaceName?.takeIf { it.isNotBlank() }

src/apps/mobile/android/app/src/main/kotlin/com/openbitfun/mobile/app/ui/remote/RemoteSessionListView.kt

@@ -297,7 +297,10 @@ internal fun RemoteSessionListContent(
                                 settings = viewSettings,
                                 projectChild = section is SessionListSection.Project,
                                 selected = session.id == state.selectedSessionId,
-                                enabled = !state.busy,
+                                // Opening a session is cancellable/supersedable
+                                // in the store; keep rows tappable while the
+                                // previous transcript hydrates.
+                                enabled = true,
                                 onOpen = {
                                     onIntent(RemoteSessionIntent.Open(session.id))
                                     onOpen(session.id)

src/apps/mobile/android/app/src/main/kotlin/com/openbitfun/mobile/app/ui/shell/OpenBitFunCompactDrawer.kt

@@ -283,7 +283,11 @@ internal fun OpenBitFunCompactDrawer(
                 Box(
                     Modifier
                         .fillMaxSize()
-                        .background(androidx.compose.material3.MaterialTheme.colorScheme.background)
+                        // Use the semantic scrim token. Using the page
+                        // background here makes a light-theme drawer paint a
+                        // white sheet over the entire detail page, so opening
+                        // the sidebar looks like the page disappeared.
+                        .background(androidx.compose.material3.MaterialTheme.colorScheme.scrim)
                         .graphicsLayer { alpha = scrimProgress.value }
                         .clickable(
                             enabled = open,

src/apps/mobile/android/app/src/main/res/values-zh/strings.xml

@@ -438,6 +438,7 @@
     <string name="remote_settings_openbitfun_user">OpenBitFun 用户</string>
     <string name="remote_settings_account_signed_in">已认证</string>
     <string name="chat_load_older_messages">加载更早消息</string>
+    <string name="chat_transcript_syncing">正在同步</string>
     <string name="account_open_github">打开 OpenBitFun 授权</string>
     <string name="account_device_link_invalid">请使用当前版本的 OpenBitFun 设备二维码。</string>
     <string name="account_device_link_unavailable">该设备已离线，或不属于当前 OpenBitFun 账户。</string>

src/apps/mobile/android/app/src/main/res/values/strings.xml

@@ -80,6 +80,7 @@
     <string name="general_chat_invalid_response">The model service returned an unrecognized response.</string>
     <string name="general_chat_network">Could not reach the provider.</string>
     <string name="chat_load_older_messages">Load earlier messages</string>
+    <string name="chat_transcript_syncing">Syncing</string>
 
     <string name="model_service_title">Model</string>
     <string name="model_service_local_title">Local custom model</string>

src/apps/mobile/android/app/src/test/kotlin/com/openbitfun/mobile/app/ui/chat/ConversationScrollPolicyTest.kt

@@ -57,10 +57,10 @@ class ConversationScrollPolicyTest {
     }
 
     @Test
-    fun lastItemIndexAccountsForTheLoadOlderHeader() {
-        org.junit.Assert.assertEquals(2, ConversationScrollPolicy.lastItemIndex(rowCount = 3, hasMoreMessages = false))
-        org.junit.Assert.assertEquals(3, ConversationScrollPolicy.lastItemIndex(rowCount = 3, hasMoreMessages = true))
-        org.junit.Assert.assertEquals(0, ConversationScrollPolicy.lastItemIndex(rowCount = 0, hasMoreMessages = false))
-        org.junit.Assert.assertEquals(0, ConversationScrollPolicy.lastItemIndex(rowCount = 0, hasMoreMessages = true))
+    fun lastItemIndexAccountsForTheLeadingHeader() {
+        org.junit.Assert.assertEquals(2, ConversationScrollPolicy.lastItemIndex(rowCount = 3, hasLeadingItem = false))
+        org.junit.Assert.assertEquals(3, ConversationScrollPolicy.lastItemIndex(rowCount = 3, hasLeadingItem = true))
+        org.junit.Assert.assertEquals(0, ConversationScrollPolicy.lastItemIndex(rowCount = 0, hasLeadingItem = false))
+        org.junit.Assert.assertEquals(0, ConversationScrollPolicy.lastItemIndex(rowCount = 0, hasLeadingItem = true))
     }
 }