feat(#396): native approval UI for dangerous command, memory, and skill write requests (#397)

* feat(ws): add ApprovalRequest event type and parser

* feat(model): add ApprovalInfo field to ChatMessage

* feat(viewmodel): handle approval.request events and respondToApproval

* feat(ui): render Approve/Deny buttons for approval request messages

* test: add approval request event and respond RPC tests

* fix: add ApprovalRequest branch to ChatWsEventReducer exhaustive when

---------

Co-authored-by: M57 <hy4ri@users.noreply.github.com>

app/src/main/java/com/m57/hermescontrol/data/ws/EventParser.kt

@@ -105,6 +105,15 @@ object EventParser {
                 WsEvent.SessionUpdated(payload)
             }
 
+            "approval.request" -> {
+                val command = payload?.get("command") as? String
+                val description = payload?.get("description") as? String
+
+                @Suppress("UNCHECKED_CAST")
+                val patternKeys = (payload?.get("pattern_keys") as? List<*>)?.filterIsInstance<String>()
+                WsEvent.ApprovalRequest(command, description, patternKeys, sessionId)
+            }
+
             else -> {
                 Log.w(TAG, "Unknown event type: $eventType")
                 WsEvent.Unknown(rawJson)

app/src/main/java/com/m57/hermescontrol/data/ws/WsEvent.kt

@@ -85,6 +85,15 @@ sealed class WsEvent {
         val error: JsonRpcError,
     ) : WsEvent()
 
+    // ── Approval request ────────────────────────────────────────────────
+
+    data class ApprovalRequest(
+        val command: String?,
+        val description: String?,
+        val patternKeys: List<String>?,
+        val sessionId: String?,
+    ) : WsEvent()
+
     // ── Fallback ─────────────────────────────────────────────────────────
 
     data class Unknown(

app/src/main/java/com/m57/hermescontrol/ui/chat/ChatBubble.kt

@@ -26,17 +26,22 @@ import androidx.compose.foundation.layout.height
 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.layout.widthIn
 import androidx.compose.foundation.shape.RoundedCornerShape
 import androidx.compose.foundation.text.selection.SelectionContainer
 import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.filled.Build
+import androidx.compose.material.icons.filled.Check
 import androidx.compose.material.icons.filled.CheckCircle
+import androidx.compose.material.icons.filled.Close
 import androidx.compose.material.icons.filled.ContentCopy
 import androidx.compose.material.icons.filled.Error
+import androidx.compose.material3.ButtonDefaults
 import androidx.compose.material3.Card
 import androidx.compose.material3.CardDefaults
 import androidx.compose.material3.CircularProgressIndicator
+import androidx.compose.material3.FilledTonalButton
 import androidx.compose.material3.Icon
 import androidx.compose.material3.IconButton
 import androidx.compose.material3.MaterialTheme
@@ -95,6 +100,7 @@ fun ChatBubble(
     isDarkTheme: Boolean,
     searchQuery: String = "",
     isCurrentMatch: Boolean = false,
+    onRespondApproval: (String) -> Unit = {},
     modifier: Modifier = Modifier,
 ) {
     val screenWidth = LocalConfiguration.current.screenWidthDp.dp
@@ -125,7 +131,11 @@ fun ChatBubble(
             }
 
             MessageRole.SYSTEM -> {
-                SystemBubble(message, modifier)
+                SystemBubble(
+                    message = message,
+                    onRespondApproval = onRespondApproval,
+                    modifier = modifier,
+                )
             }
 
             MessageRole.TOOL -> {
@@ -415,14 +425,15 @@ private fun AssistantBubble(
 @Composable
 private fun SystemBubble(
     message: ChatMessage,
+    onRespondApproval: (String) -> Unit = {},
     modifier: Modifier = Modifier,
 ) {
-    Box(
+    Column(
         modifier =
             modifier
                 .fillMaxWidth()
                 .padding(horizontal = 16.dp, vertical = 4.dp),
-        contentAlignment = Alignment.Center,
+        horizontalAlignment = Alignment.CenterHorizontally,
     ) {
         Text(
             text = message.content,
@@ -432,6 +443,54 @@ private fun SystemBubble(
                     color = SystemMessageColor,
                 ),
         )
+
+        // Approval action buttons
+        if (message.approvalInfo != null) {
+            Spacer(Modifier.height(8.dp))
+            Row(
+                horizontalArrangement = Arrangement.spacedBy(8.dp),
+            ) {
+                FilledTonalButton(
+                    onClick = { onRespondApproval("approve") },
+                    modifier =
+                        Modifier
+                            .height(36.dp)
+                            .testTag("approve_button"),
+                    colors =
+                        ButtonDefaults.filledTonalButtonColors(
+                            containerColor = MaterialTheme.colorScheme.primaryContainer,
+                        ),
+                ) {
+                    Icon(
+                        imageVector = Icons.Filled.Check,
+                        contentDescription = null,
+                        modifier = Modifier.size(16.dp),
+                    )
+                    Spacer(Modifier.width(4.dp))
+                    Text("Approve")
+                }
+
+                FilledTonalButton(
+                    onClick = { onRespondApproval("deny") },
+                    modifier =
+                        Modifier
+                            .height(36.dp)
+                            .testTag("deny_button"),
+                    colors =
+                        ButtonDefaults.filledTonalButtonColors(
+                            containerColor = MaterialTheme.colorScheme.errorContainer,
+                        ),
+                ) {
+                    Icon(
+                        imageVector = Icons.Filled.Close,
+                        contentDescription = null,
+                        modifier = Modifier.size(16.dp),
+                    )
+                    Spacer(Modifier.width(4.dp))
+                    Text("Deny")
+                }
+            }
+        }
     }
 }
 

app/src/main/java/com/m57/hermescontrol/ui/chat/ChatMessage.kt

@@ -2,6 +2,17 @@ package com.m57.hermescontrol.ui.chat
 
 import java.util.UUID
 
+/**
+ * Metadata for a [ChatMessage] that represents an approval request.
+ * When present, the UI renders Approve/Deny buttons inline.
+ * Transient — not persisted to SQLite.
+ */
+data class ApprovalInfo(
+    val command: String?,
+    val description: String?,
+    val patternKeys: List<String>?,
+)
+
 data class ChatMessage(
     val id: String = UUID.randomUUID().toString(),
     val role: MessageRole,
@@ -10,6 +21,7 @@ data class ChatMessage(
     val isStreaming: Boolean = false,
     val toolName: String? = null,
     val toolStatus: ToolStatus? = null,
+    val approvalInfo: ApprovalInfo? = null,
 )
 
 enum class MessageRole {

app/src/main/java/com/m57/hermescontrol/ui/chat/ChatScreen.kt

@@ -1119,6 +1119,7 @@ private fun ChatMessageList(
                     isDarkTheme = isDark,
                     searchQuery = if (isSearchActive) searchQuery else "",
                     isCurrentMatch = isCurrentMatch,
+                    onRespondApproval = viewModel::respondToApproval,
                 )
             }
         }

app/src/main/java/com/m57/hermescontrol/ui/chat/ChatViewModel.kt

@@ -269,6 +269,10 @@ class ChatViewModel(
                 }
             }
 
+            is WsEvent.ApprovalRequest -> {
+                handleApprovalRequest(event)
+            }
+
             else -> { /* reducer handles these */ }
         }
     }
@@ -437,6 +441,14 @@ class ChatViewModel(
             WsMethods.COMMAND_DISPATCH -> {
                 handleDispatchResult(result)
             }
+
+            WsMethods.APPROVAL_RESPOND -> {
+                val map = result as? Map<*, *>
+                val resolved = (map?.get("resolved") as? Number)?.toInt() ?: 0
+                if (resolved > 0) {
+                    addSystemMessage("✅ Approval submitted")
+                }
+            }
         }
     }
 
@@ -947,6 +959,63 @@ class ChatViewModel(
         _uiState.update { it.copy(errorMessage = null) }
     }
 
+    // ── Approval flow ───────────────────────────────────────────────────
+
+    private fun handleApprovalRequest(event: WsEvent.ApprovalRequest) {
+        val description = event.description ?: event.command ?: "Unknown command"
+        val content = "⚠️ **Approval Required**\n$description"
+        val msg =
+            ChatMessage(
+                role = MessageRole.SYSTEM,
+                content = content,
+                approvalInfo =
+                    ApprovalInfo(
+                        command = event.command,
+                        description = event.description,
+                        patternKeys = event.patternKeys,
+                    ),
+            )
+        _uiState.update { state ->
+            state.copy(
+                messages = state.messages + msg,
+                isAgentTyping = false,
+            )
+        }
+    }
+
+    fun respondToApproval(action: String) {
+        val state = _uiState.value
+        val approvalMsg = state.messages.lastOrNull { it.approvalInfo != null } ?: return
+        val sessionId = state.currentSessionId ?: return
+
+        // Clear buttons immediately
+        _uiState.update { s ->
+            s.copy(
+                messages =
+                    s.messages.map {
+                        if (it.id == approvalMsg.id) {
+                            it.copy(approvalInfo = null)
+                        } else {
+                            it
+                        }
+                    },
+            )
+        }
+
+        viewModelScope.launch(Dispatchers.IO) {
+            wsClient.send(
+                method = WsMethods.APPROVAL_RESPOND,
+                params =
+                    mapOf(
+                        "session_id" to sessionId,
+                        "choice" to action,
+                        "all" to false,
+                    ),
+                onSent = { id -> trackRequest(id, WsMethods.APPROVAL_RESPOND) },
+            )
+        }
+    }
+
     fun reconnect() {
         _uiState.update {
             it.copy(

app/src/main/java/com/m57/hermescontrol/ui/chat/ChatWsEventReducer.kt

@@ -72,6 +72,9 @@ object ChatWsEventReducer {
 
             // RpcResult is handled by the ViewModel (needs pending request context)
             is WsEvent.RpcResult -> ReducerResult(state)
+
+            // ApprovalRequest is handled by the ViewModel (needs active session + WS client)
+            is WsEvent.ApprovalRequest -> ReducerResult(state)
         }
 
     // ── GatewayReady ──────────────────────────────────────────────────