added selection for level to export

src/main.rs

@@ -114,7 +114,12 @@ impl Drop for DungeonApp {
 impl eframe::App for DungeonApp {
     // Render UI, handle input, and update app state each frame.
     fn update(&mut self, ctx: &egui::Context, _frame: &mut eframe::Frame) {
-        let panel_result = draw_side_panel(ctx, &mut self.settings, self.export_rx.is_some());
+        let panel_result = draw_side_panel(
+            ctx,
+            &mut self.settings,
+            self.export_rx.is_some(),
+            self.levels.len(),
+        );
         let undo_requested = ctx.input(|i| i.modifiers.command && i.key_pressed(egui::Key::Z));
         let redo_requested = ctx.input(|i| {
             (i.modifiers.command && i.key_pressed(egui::Key::Y))
@@ -218,8 +223,12 @@ impl eframe::App for DungeonApp {
                 }
             }
 
-            if self.settings.active_level_index < self.levels.len() {
-                let layout = self.levels[self.settings.active_level_index].clone();
+            let export_idx = self
+                .settings
+                .export_level_index
+                .min(self.levels.len().saturating_sub(1));
+            if export_idx < self.levels.len() {
+                let layout = self.levels[export_idx].clone();
                 let settings = self.settings.clone();
                 let (tx, rx) = mpsc::channel();
                 thread::spawn(move || {

src/ui.rs

@@ -145,6 +145,7 @@ pub struct UiSettings {
     pub min_levels: usize,
     pub max_levels: usize,
     pub active_level_index: usize,
+    pub export_level_index: usize,
     pub trap_frequency_percent: usize,
     pub min_traps_per_area: usize,
     pub max_traps_per_area: usize,
@@ -223,6 +224,7 @@ impl Default for UiSettings {
             max_stairs_per_level: 2,
             sync_stairs_across_levels: false,
             manual_stair_size: 2,
+            export_level_index: 0,
             active_tab: Tab::Generate,
         }
     }
@@ -260,6 +262,7 @@ pub fn draw_side_panel(
     ctx: &egui::Context,
     settings: &mut UiSettings,
     export_in_progress: bool,
+    num_levels: usize,
 ) -> SidePanelResult {
     // Render the left side panel and return user interaction results.
     let mut result = SidePanelResult::default();
@@ -307,7 +310,7 @@ pub fn draw_side_panel(
 
                 match settings.active_tab {
                     Tab::Generate => {
-                        draw_generate_tab(ui, settings, &mut result, export_in_progress)
+                        draw_generate_tab(ui, settings, &mut result, export_in_progress, num_levels)
                     }
                     Tab::Layout => draw_layout_tab(ui, settings, &mut result),
                     Tab::StartAndEnd => draw_start_and_end_tab(ui, settings, &mut result),
@@ -326,6 +329,7 @@ fn draw_generate_tab(
     settings: &mut UiSettings,
     result: &mut SidePanelResult,
     export_in_progress: bool,
+    num_levels: usize,
 ) {
     ui.label(RichText::new("Grid Settings").strong());
     ui.add_space(8.0);
@@ -424,6 +428,23 @@ fn draw_generate_tab(
             });
     });
 
+    ui.add_space(4.0);
+    let level_count = num_levels;
+    ui.horizontal(|ui| {
+        ui.label("Level");
+        egui::ComboBox::from_id_salt("export_level")
+            .selected_text(format!("Level {}", settings.export_level_index))
+            .show_ui(ui, |ui| {
+                for i in 0..level_count {
+                    ui.selectable_value(
+                        &mut settings.export_level_index,
+                        i,
+                        format!("Level {}", i),
+                    );
+                }
+            });
+    });
+
     if settings.export_format == ExportFormat::Folder {
         ui.add_space(6.0);
         ui.horizontal(|ui| {