validity of host

apps/multiplatform/common/src/commonMain/kotlin/chat/simplex/common/views/usersettings/NetworkAndServers.kt

@@ -290,6 +290,7 @@ fun SocksProxySettings(
     ) ||
         !validCredential(usernameUnsaved.value.text) ||
         !validCredential(passwordUnsaved.value.text) ||
+        !validHost(hostUnsaved.value.text) ||
         !validPort(portUnsaved.value.text)
   val resetDisabled = hostUnsaved.value.text.trim() == "localhost" && portUnsaved.value.text.trim() == "9050" && proxyAuthRandomUnsaved.value && onionHosts.value == NetCfg.defaults.onionHosts
   ModalView(
@@ -316,7 +317,7 @@ fun SocksProxySettings(
             hostUnsaved,
             stringResource(MR.strings.host_verb),
             modifier = Modifier.fillMaxWidth(),
-            isValid = { true },
+            isValid = ::validHost,
             keyboardActions = KeyboardActions(onNext = { defaultKeyboardAction(ImeAction.Next) }),
             keyboardType = KeyboardType.Text,
           )
@@ -483,6 +484,9 @@ fun SessionModePicker(
   )
 }
 
+private fun validHost(s: String): Boolean =
+  !s.contains('@')
+
 // https://ihateregex.io/expr/port/
 fun validPort(s: String): Boolean {
   val validPort = Regex("^(6553[0-5])|(655[0-2][0-9])|(65[0-4][0-9]{2})|(6[0-4][0-9]{3})|([1-5][0-9]{4})|([0-5]{0,5})|([0-9]{1,4})$")