better ux, how to inform when file already exists

app/src/main/java/sh/sar/isodroid/ui/components/CreateImgDialog.kt

@@ -60,6 +60,7 @@ data class CreateImgProgress(
 @Composable
 fun CreateImgDialog(
     progress: CreateImgProgress,
+    existingFiles: List<String> = emptyList(),
     onDismiss: () -> Unit,
     onConfirm: (CreateImgOptions) -> Unit,
     onCancel: () -> Unit
@@ -68,9 +69,13 @@ fun CreateImgDialog(
     var sizeValue by remember { mutableStateOf("") }
     var sizeUnit by remember { mutableStateOf(SizeUnit.GB) }
 
+    val fullFileName = if (fileName.isNotBlank()) "$fileName.img" else ""
+    val fileExists = fullFileName.isNotEmpty() && existingFiles.contains(fullFileName)
+
     val isValidInput = fileName.isNotBlank() &&
             !fileName.contains("/") &&
-            sizeValue.toLongOrNull()?.let { it > 0 } == true
+            sizeValue.toLongOrNull()?.let { it > 0 } == true &&
+            !fileExists
 
     AlertDialog(
         onDismissRequest = {
@@ -129,9 +134,20 @@ fun CreateImgDialog(
                         label = { Text("File Name") },
                         suffix = { Text(".img") },
                         singleLine = true,
+                        isError = fileExists,
                         modifier = Modifier.fillMaxWidth()
                     )
 
+                    // Show error if file exists
+                    if (fileExists) {
+                        Spacer(modifier = Modifier.height(8.dp))
+                        Text(
+                            text = "A file with this name already exists. Please choose a different name.",
+                            style = MaterialTheme.typography.bodySmall,
+                            color = MaterialTheme.colorScheme.error
+                        )
+                    }
+
                     Spacer(modifier = Modifier.height(16.dp))
 
                     // Size input

app/src/main/java/sh/sar/isodroid/ui/screens/MainScreen.kt

@@ -207,6 +207,7 @@ fun MainScreen(
     if (showCreateImgDialog || uiState.createImgProgress.isCreating) {
         CreateImgDialog(
             progress = uiState.createImgProgress,
+            existingFiles = uiState.isoFiles.map { it.name },
             onDismiss = {
                 showCreateImgDialog = false
             },

app/src/main/java/sh/sar/isodroid/viewmodel/MainViewModel.kt

@@ -417,13 +417,6 @@ class MainViewModel(application: Application) : AndroidViewModel(application) {
             val filePath = "${_uiState.value.currentPath}/$fileName"
             val totalBytes = options.totalBytes
 
-            // Check if file already exists
-            val checkResult = RootManager.executeCommand("test -f \"$filePath\" && echo exists")
-            if (checkResult.output.trim() == "exists") {
-                _uiState.update { it.copy(errorMessage = "File already exists: $fileName") }
-                return@launch
-            }
-
             // Start creating
             _uiState.update {
                 it.copy(