From c34d9a797a499e232a0b5ee075ad6e38958bd89a Mon Sep 17 00:00:00 2001
From: Sergej Pavlenko <sergepav0@gmail.com>
Date: Thu, 20 Nov 2025 01:34:23 +0100
Subject: [PATCH] =?utf8?q?Liste=20f=C3=BCr=20Treibstoffbestand=20bei=20ein?=
 =?utf8?q?er=20oder=20mehreren=20Tankstellen=20hinzugef=C3=BCgt?=
MIME-Version: 1.0
Content-Type: text/plain; charset=utf8
Content-Transfer-Encoding: 8bit

---
 .../tankstelle/FuelStationUI.java             | 66 +++++++++++++++++--
 1 file changed, 60 insertions(+), 6 deletions(-)

diff --git a/src/main/java/de/diejungsvondertanke/tankstelle/FuelStationUI.java b/src/main/java/de/diejungsvondertanke/tankstelle/FuelStationUI.java
index abfbae9..a64f934 100644
--- a/src/main/java/de/diejungsvondertanke/tankstelle/FuelStationUI.java
+++ b/src/main/java/de/diejungsvondertanke/tankstelle/FuelStationUI.java
@@ -17,6 +17,7 @@ public class FuelStationUI extends JFrame {
     private JComboBox<FuelType> comboFuelTypes;
     private JTextArea outputArea;
     private JPanel contentPane;
+    private JList<String> listFuelStations;
 
     public FuelStationUI() {
         setContentPane(contentPane);
@@ -41,6 +42,11 @@ public class FuelStationUI extends JFrame {
         comboFuelStations = new JComboBox<>(buildStationNames());
         comboFuelTypes = new JComboBox<>(FuelType.values());
 
+        listFuelStations = new JList<>();
+        listFuelStations.setSelectionMode(ListSelectionModel.MULTIPLE_INTERVAL_SELECTION);
+
+        refreshStationNames();
+
         selectionPanel.add(new JLabel("Fuel station:"));
         selectionPanel.add(comboFuelStations);
         selectionPanel.add(new JLabel("Fuel type:"));
@@ -107,7 +113,9 @@ public class FuelStationUI extends JFrame {
      * @author Sergej Pavlenko
      */
     private JPanel createResultPanel() {
-        JPanel panel = new JPanel(new GridLayout(0, 1, 5, 5));
+        JPanel panel = new JPanel(new BorderLayout());
+
+        JPanel buttonPanel = new JPanel(new GridLayout(0, 1, 5, 5));
 
         JButton btnTotalPrice = new JButton("Total selling value of all available fuel types");
         btnTotalPrice.addActionListener(e -> {
@@ -156,10 +164,41 @@ public class FuelStationUI extends JFrame {
             }
         });
 
-        panel.add(btnTotalPrice);
-        panel.add(btnHighestPrice);
-        panel.add(btnHighestTotalValue);
-        panel.add(btnStock);
+        JButton btnTotalStock = new JButton("Total stock (chosen fuel station, chosen fuel type)");
+        btnTotalStock.addActionListener(e -> {
+            FuelType type = (FuelType) comboFuelTypes.getSelectedItem();
+            int[] indices = listFuelStations.getSelectedIndices();
+
+            if (indices.length == 0) {
+                showError("Please select at least one fuel station.");
+                return;
+            }
+
+            FuelStation[] selectedStations = new FuelStation[indices.length];
+            for (int i = 0; i < indices.length; i++) {
+                selectedStations[i] = Main.fuelStations.get(indices[i]);
+            }
+
+            float total = Main.getTotalStockLevelOfFuel(type, selectedStations);
+            appendOutput(String.format("Total stock of %s across %d chosen fuel stations: %.2f L", type, indices.length, total));
+        });
+
+        buttonPanel.add(btnTotalPrice);
+        buttonPanel.add(btnHighestPrice);
+        buttonPanel.add(btnHighestTotalValue);
+        buttonPanel.add(btnStock);
+        buttonPanel.add(btnTotalStock);
+
+        JScrollPane listScroller = new JScrollPane(listFuelStations);
+        listScroller.setPreferredSize(new Dimension(250, 0));
+
+        JPanel listPanel = new JPanel(new BorderLayout());
+        listPanel.add(new JLabel("Fuel station selection (multiple possible):"), BorderLayout.NORTH);
+        listPanel.add(listFuelStations, BorderLayout.CENTER);
+
+        panel.add(buttonPanel, BorderLayout.CENTER);
+        panel.add(listScroller, BorderLayout.EAST);
+        panel.add(listPanel, BorderLayout.EAST);
 
         return panel;
     }
@@ -439,7 +478,22 @@ public class FuelStationUI extends JFrame {
         return panel;
     }
 
-    // ------------------ HILFSMETHODEN ------------------
+    /**
+     * Refreshes ComboBox and List together
+     *
+     * @author Sergej Pavlenko
+     */
+    private void refreshStationNames() {
+        String[] names = buildStationNames();
+
+        if (comboFuelStations != null) {
+            comboFuelStations.setModel(new DefaultComboBoxModel<>(names));
+        }
+
+        if (listFuelStations != null) {
+            listFuelStations.setListData(names);
+        }
+    }
 
     private String getDisplayName(FuelStation station) {
         int index = Main.fuelStations.indexOf(station);
-- 
2.43.0