feat: add apply button and input handler

app/src/main/java/ru/risdeveau/geotracker/API.kt

@@ -30,8 +30,10 @@ data class GeoData(
  * @return true if baseurl is valid
  */
 suspend fun health(baseurl: String): Boolean {
-    val r = client.get("$baseurl/health")
-    return r.status == HttpStatusCode.OK
+    try {
+        val r = client.get("$baseurl/health")
+        return r.status == HttpStatusCode.OK
+    } catch (_: Exception) { return false }
 }
 
 /**

app/src/main/java/ru/risdeveau/geotracker/MainActivity.kt

@@ -12,7 +12,10 @@ import androidx.activity.enableEdgeToEdge
 import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
+import androidx.compose.material3.Button
 import androidx.compose.material3.CircularProgressIndicator
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.OutlinedTextField
@@ -29,10 +32,14 @@ import androidx.compose.ui.Modifier
 import androidx.compose.ui.text.TextStyle
 import androidx.compose.ui.text.font.FontStyle
 import androidx.compose.ui.text.style.TextDecoration
+import androidx.compose.ui.unit.dp
+import kotlinx.coroutines.delay
 import kotlinx.coroutines.launch
+import org.intellij.lang.annotations.JdkConstants
 import ru.risdeveau.geotracker.ui.theme.GeoTrackerTheme
 import splitties.resources.appColor
 import splitties.resources.appStr
+import kotlin.apply
 
 class MainActivity : ComponentActivity() {
     override fun onCreate(savedInstanceState: Bundle?) {
@@ -87,9 +94,19 @@ sealed class Screen {
 fun Settings(modifier: Modifier = Modifier) {
     var username by remember { mutableStateOf("") }
     var url by remember { mutableStateOf("") }
+    var urlIsValid by remember { mutableStateOf(false) }
+    var loading by remember { mutableStateOf(false) }
 
+    LaunchedEffect(url) {
+        if (url.isNotEmpty()) {
+            delay(1000)
+            loading = true
+            urlIsValid = health(url)
+            loading = false
+        }
+    }
 
-    Column (modifier = modifier) {
+    Column (modifier = modifier, horizontalAlignment = Alignment.CenterHorizontally) {
         OutlinedTextField(
             value = username,
             onValueChange = { username = it },
@@ -100,7 +117,12 @@ fun Settings(modifier: Modifier = Modifier) {
             value = url,
             onValueChange = { url = it },
             placeholder = { Text("https://geo.example.com", style = TextStyle(color = MaterialTheme.colorScheme.onSurfaceVariant)) },
-            label = { Text(appStr(R.string.server_url)) }
+            label = { Text(appStr(R.string.server_url)) },
+            trailingIcon = { if (loading) CircularProgressIndicator() }
         )
+
+        Button({}, enabled = urlIsValid) {
+            Text(appStr(R.string.apply))
+        }
     }
 }