Add warning if network unavailable

app/src/main/java/com/bitchat/android/nostr/NostrGeohashService.kt

@@ -108,6 +108,18 @@ class NostrGeohashService(
         coroutineScope.launch {
             val nostrRelayManager = NostrRelayManager.getInstance(application)
 
+            // Set up network error callback to display system messages
+            NostrRelayManager.setNetworkErrorCallback { errorMessage ->
+                // Display network error as a system message in chat
+                val systemMessage = BitchatMessage(
+                    sender = "system",
+                    content = errorMessage,
+                    timestamp = Date(),
+                    isRelay = false
+                )
+                messageManager.addMessage(systemMessage)
+            }
+
             // Connect to relays
             nostrRelayManager.connect()
 
@@ -153,6 +165,9 @@ class NostrGeohashService(
 
                 // 2) Clear all subscription tracking and caches
                 relayManager.clearAllSubscriptions()
+
+                // Clear network error callback
+                NostrRelayManager.clearNetworkErrorCallback()
 
                 // 3) Clear Nostr identity (npub/private) and geohash identity cache/seed
                 try {
@@ -206,6 +221,27 @@ class NostrGeohashService(
         }
     }
 
+    /**
+     * Clean up the service and release resources
+     * Should be called when the service is no longer needed
+     */
+    fun cleanup() {
+        try {
+            // Clear the network error callback
+            NostrRelayManager.clearNetworkErrorCallback()
+
+            // Cancel any running jobs
+            geohashSamplingJob?.cancel()
+            geohashSamplingJob = null
+            geoParticipantsTimer?.cancel()
+            geoParticipantsTimer = null
+
+            Log.d(TAG, "NostrGeohashService cleaned up")
+        } catch (e: Exception) {
+            Log.e(TAG, "Error during cleanup: ${e.message}")
+        }
+    }
+
     /**
      * Initialize location channel state
      */

app/src/main/java/com/bitchat/android/nostr/NostrRelayManager.kt

@@ -24,6 +24,39 @@ class NostrRelayManager private constructor() {
         val shared = NostrRelayManager()
 
         private const val TAG = "NostrRelayManager"
+        private const val NETWORK_ERROR_MESSAGE = "Network unreachable. Please ensure the device is connected and has all necessary permissions."
+
+        // Network error callback for reporting failures to UI
+        @Volatile
+        private var networkErrorCallback: ((String) -> Unit)? = null
+        @Volatile
+        private var hasReportedNetworkError = false
+
+        /**
+         * Set callback for network error reporting
+         * Throws IllegalStateException if a callback is already set
+         */
+        fun setNetworkErrorCallback(callback: (String) -> Unit) {
+            if (networkErrorCallback != null) {
+                throw IllegalStateException("Network error callback already set. Only one service instance should be active.")
+            }
+            networkErrorCallback = callback
+        }
+
+        /**
+         * Clear the network error callback (should be called when service is destroyed)
+         */
+        fun clearNetworkErrorCallback() {
+            networkErrorCallback = null
+            hasReportedNetworkError = false
+        }
+
+        /**
+         * Reset network error flag (e.g., when network comes back)
+         */
+        fun resetNetworkErrorFlag() {
+            hasReportedNetworkError = false
+        }
 
         /**
          * Get instance for Android compatibility (context-aware calls)
@@ -644,8 +677,18 @@ class NostrRelayManager private constructor() {
                 val relay = relaysList.find { it.url == relayUrl }
                 relay?.messagesSent = (relay?.messagesSent ?: 0) + 1
                 updateRelaysList()
+                // Reset error flag on successful send
+                hasReportedNetworkError = false
             } else {
                 Log.e(TAG, "❌ Failed to send event to $relayUrl: WebSocket send failed")
+
+                // Check if all relays are disconnected (likely network issue)
+                if (connections.isEmpty() || relaysList.none { it.isConnected }) {
+                    if (!hasReportedNetworkError) {
+                        hasReportedNetworkError = true
+                        networkErrorCallback?.invoke(NETWORK_ERROR_MESSAGE)
+                    }
+                }
             }
         } catch (e: Exception) {
             Log.e(TAG, "❌ Failed to send event to $relayUrl: ${e.message}")

app/src/main/java/com/bitchat/android/ui/ChatViewModel.kt

@@ -184,6 +184,8 @@ class ChatViewModel(
 
     override fun onCleared() {
         super.onCleared()
+        // Clean up NostrGeohashService
+        nostrGeohashService.cleanup()
         // Note: Mesh service lifecycle is now managed by MainActivity
     }