refactor: extract BrightnessUtils, use snackbar instead of toast

app/src/main/java/com/bitcointxoko/gudariwallet/ui/common/BrightnessUtils.kt

@@ -0,0 +1,41 @@
+package com.bitcointxoko.gudariwallet.ui.common
+
+import android.app.Activity
+import android.view.WindowManager
+import androidx.compose.runtime.*
+import androidx.compose.ui.platform.LocalContext
+
+/**
+ * Manages screen brightness for QR-display screens.
+ * Returns a [BrightnessController] with [isOn] state and a [toggle] callback.
+ * Restores system brightness unconditionally when it leaves composition.
+ */
+@Composable
+fun rememberBrightnessController(): BrightnessController {
+    val window = (LocalContext.current as? Activity)?.window
+    var isOn by remember { mutableStateOf(false) }
+
+    LaunchedEffect(isOn) {
+        window?.attributes = window?.attributes?.apply {
+            screenBrightness = if (isOn) 1f
+            else WindowManager.LayoutParams.BRIGHTNESS_OVERRIDE_NONE
+        }
+    }
+
+    DisposableEffect(Unit) {
+        onDispose {
+            window?.attributes = window?.attributes?.apply {
+                screenBrightness = WindowManager.LayoutParams.BRIGHTNESS_OVERRIDE_NONE
+            }
+        }
+    }
+
+    return remember(isOn) {
+        BrightnessController(isOn = isOn, toggle = { isOn = !isOn })
+    }
+}
+
+data class BrightnessController(
+    val isOn   : Boolean,
+    val toggle : () -> Unit
+)

app/src/main/java/com/bitcointxoko/gudariwallet/ui/nwc/NwcPairingDialog.kt

@@ -23,35 +23,19 @@ import androidx.compose.ui.Modifier
 import androidx.compose.ui.platform.LocalContext
 import androidx.compose.ui.unit.dp
 import androidx.core.net.toUri
+import com.bitcointxoko.gudariwallet.ui.common.rememberBrightnessController
 import com.bitcointxoko.gudariwallet.ui.receive.QrDisplayCard
 
 @Composable
 internal fun NwcPairingUrlDialog(
     url       : String,
-    onDismiss : () -> Unit
+    onDismiss : () -> Unit,
+    onNoAppFound  : () -> Unit
 ) {
     // Brightness state lives here so the dialog owns the screen-brightness side-effect
-    var brightnessOn by remember { mutableStateOf(false) }
-    val window = (LocalContext.current as? Activity)?.window
+    val brightness = rememberBrightnessController()
     val context = LocalContext.current
 
-    // Boost / restore screen brightness when the toggle changes
-    LaunchedEffect(brightnessOn) {
-        window?.attributes = window.attributes?.apply {
-            screenBrightness = if (brightnessOn) 1f
-            else WindowManager.LayoutParams.BRIGHTNESS_OVERRIDE_NONE
-        }
-    }
-
-    // Restore brightness unconditionally when the dialog leaves composition
-    DisposableEffect(Unit) {
-        onDispose {
-            window?.attributes = window.attributes?.apply {
-                screenBrightness = WindowManager.LayoutParams.BRIGHTNESS_OVERRIDE_NONE
-            }
-        }
-    }
-
     AlertDialog(
         onDismissRequest = onDismiss,
         title = { Text("Connection created") },
@@ -63,31 +47,24 @@ internal fun NwcPairingUrlDialog(
                     color = MaterialTheme.colorScheme.onSurfaceVariant
                 )
                 QrDisplayCard(
-                    modifier             = Modifier.fillMaxWidth(),
-                    content              = url,
-                    contentDescription   = "NWC pairing QR code",
-                    clipLabel            = "NWC connection string",
-                    shareTitle           = "Share NWC connection string",
-                    textToCopy           = url,
-                    brightnessOn         = brightnessOn,
-                    onToggleBrightness   = { brightnessOn = !brightnessOn },
-                    // No NFC for a one-shot pairing string
-                    isNfcEmulating       = null,
-                    qrModifier           = Modifier.fillMaxWidth(),
-                    onOpenUri = {
+                    modifier           = Modifier.fillMaxWidth(),
+                    content            = url,
+                    contentDescription = "NWC pairing QR code",
+                    clipLabel          = "NWC connection string",
+                    shareTitle         = "Share NWC connection string",
+                    textToCopy         = url,
+                    brightnessOn       = brightness.isOn,
+                    onToggleBrightness = brightness.toggle,
+                    isNfcEmulating     = null,
+                    qrModifier         = Modifier.fillMaxWidth(),
+                    onOpenUri          = {
                         val intent = Intent(Intent.ACTION_VIEW, url.toUri())
                         try {
                             context.startActivity(
                                 Intent.createChooser(intent, "Open in app")
                             )
                         } catch (e: ActivityNotFoundException) {
-                            // No app installed that handles nostr+walletconnect://
-                            // Show a snackbar / toast as appropriate for your app
-                            Toast.makeText(
-                                context,
-                                "No compatible app found",   // "No compatible app found"
-                                Toast.LENGTH_SHORT
-                            ).show()
+                            onNoAppFound()   // #17: no Toast — caller handles it
                         }
                     }
                 )

app/src/main/java/com/bitcointxoko/gudariwallet/ui/nwc/NwcScreen.kt

@@ -13,6 +13,7 @@ import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.unit.dp
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
+import kotlinx.coroutines.launch
 
 @OptIn(ExperimentalMaterial3Api::class)
 @Composable
@@ -27,6 +28,8 @@ fun NwcScreen(
     val pairingUrl          by viewModel.pairingUrl.collectAsStateWithLifecycle()
     val showAddSheet        by viewModel.showAddSheet.collectAsStateWithLifecycle()
     val pendingDeletePubkey by viewModel.pendingDeletePubkey.collectAsStateWithLifecycle()
+    val snackbarHostState = remember { SnackbarHostState() }
+    val scope             = rememberCoroutineScope()
 
     // ── Shared refresh lambda (item #13) ──────────────────────────────────────
     val refresh = { viewModel.loadConnections(includeExpired = true) }
@@ -46,7 +49,8 @@ fun NwcScreen(
             FloatingActionButton(onClick = { viewModel.openAddSheet() }) {
                 Icon(Icons.Default.Add, contentDescription = "Add connection")
             }
-        }
+        },
+        snackbarHost = { SnackbarHost(snackbarHostState) }
     ) { innerPadding ->
 
         val isRefreshing = uiState is NwcUiState.Loading
@@ -127,7 +131,12 @@ fun NwcScreen(
     pairingUrl?.let { url ->
         NwcPairingUrlDialog(
             url       = url,
-            onDismiss = { viewModel.clearPairingUrl() }
+            onDismiss = { viewModel.clearPairingUrl() },
+            onNoAppFound = {
+                scope.launch {
+                    snackbarHostState.showSnackbar("No compatible app found")
+                }
+            }
         )
     }