Add onConnectFailed UI callback

app/src/main/java/sushi/hardcore/aira/ChatActivity.kt

@@ -130,6 +130,7 @@ class ChatActivity : ServiceBoundActivity() {
                         binding.bottomPanel.visibility = View.VISIBLE
                     }
                     airaService.uiCallbacks = object : AIRAService.UiCallbacks {
+                        override fun onConnectFailed(ip: String, errorMsg: String?) {}
                         override fun onNewSession(sessionId: Int, ip: String) {
                             if (this@ChatActivity.sessionId == sessionId) {
                                 runOnUiThread {

app/src/main/java/sushi/hardcore/aira/MainActivity.kt

@@ -39,6 +39,15 @@ class MainActivity : ServiceBoundActivity() {
         }
     }
     private val uiCallbacks = object : AIRAService.UiCallbacks {
+        override fun onConnectFailed(ip: String, errorMsg: String?) {
+            var msg = getString(R.string.unable_to_connect_to, ip)
+            errorMsg?.let {
+                msg += ": $it"
+            }
+            runOnUiThread {
+                Toast.makeText(this@MainActivity, msg, Toast.LENGTH_SHORT).show()
+            }
+        }
         override fun onNewSession(sessionId: Int, ip: String) {
             runOnUiThread {
                 handleNewSession(sessionId, ip)

app/src/main/java/sushi/hardcore/aira/background_service/AIRAService.kt

@@ -103,6 +103,7 @@ class AIRAService : Service() {
     }
 
     interface UiCallbacks {
+        fun onConnectFailed(ip: String, errorMsg: String?)
         fun onNewSession(sessionId: Int, ip: String)
         fun onSessionDisconnect(sessionId: Int)
         fun onNameTold(sessionId: Int, name: String)
@@ -456,13 +457,20 @@ class AIRAService : Service() {
                             MESSAGE_CONNECT_TO -> {
                                 msg.data.getString("ip")?.let { ip ->
                                     Thread {
-                                        try {
-                                            val socket = SocketChannel.open()
-                                            if (socket.connect(InetSocketAddress(ip, Constants.port))) {
-                                                handleNewSocket(socket, true)
+                                        val addr = InetSocketAddress(ip, Constants.port)
+                                        if (addr.isUnresolved) {
+                                            uiCallbacks?.onConnectFailed(ip, getString(R.string.invalid_ip))
+                                        } else {
+                                            try {
+                                                val socket = SocketChannel.open()
+                                                if (socket.connect(addr)) {
+                                                    handleNewSocket(socket, true)
+                                                }
+                                            } catch (e: NoRouteToHostException) {
+                                                uiCallbacks?.onConnectFailed(ip, e.message)
+                                            } catch (e: ConnectException) {
+                                                uiCallbacks?.onConnectFailed(ip, e.message)
                                             }
-                                        } catch (e: ConnectException) {
-                                            Log.w("Connect failed", "$ip: "+e.message)
                                         }
                                     }.start()
                                 }

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

@@ -95,6 +95,7 @@
     <string name="message_hint">Send a message…</string>
     <string name="no_name_error">This session has no name !</string>
     <string name="invalid_ip">Invalid IP address</string>
+    <string name="unable_to_connect_to">Unable to connect to %s</string>
 
     <!--accessibility strings-->
     <string name="send_file">Send file</string>