warn user to expand folders before downloading them

gui/griffon-app/controllers/com/muwire/gui/BrowseController.groovy

@@ -167,6 +167,11 @@ class BrowseController {
         if (selectedResults == null || selectedResults.isEmpty())
             return
 
+        if (model.treeVisible && model.session != null && model.session.supportsIncremental() &&
+                view.resultsTree.selectedUnfetchedFolder()) {
+            view.showUnexpandedFolderWarning()
+            return
+        }
 
         File downloadsFolder = application.context.get("muwire-settings").downloadLocation
         List<ResultAndTargets> targets = view.decorateResults(selectedResults)

gui/griffon-app/i18n/messages.properties

@@ -300,6 +300,8 @@ SELECT_SINGLE_RESULT=Select a single result to see who sent it
 # Search table popup menu
 COPY_NAME_TO_CLIPBOARD=Copy name to clipboard
 EXPAND_FULLY=Expand fully
+WARNING_UNEXPANDED_FOLDER_TITLE=Cannot download folder
+WARNING_UNEXPANDED_FOLDER_BODY=Before you can download this folder you need to expand it fully
 
 ## Result details tab
 

gui/griffon-app/views/com/muwire/gui/BrowseView.groovy

@@ -5,6 +5,7 @@ import griffon.core.artifact.GriffonView
 import javax.swing.AbstractAction
 import javax.swing.Action
 import javax.swing.JComponent
+import javax.swing.JOptionPane
 import javax.swing.JPanel
 import javax.swing.JTable
 import javax.swing.JTextField
@@ -408,6 +409,11 @@ class BrowseView {
         rv
     }
     
+    void showUnexpandedFolderWarning() {
+        JOptionPane.showMessageDialog(null, trans("WARNING_UNEXPANDED_FOLDER_BODY"),
+            trans("WARNING_UNEXPANDED_FOLDER_TITLE"), JOptionPane.WARNING_MESSAGE)
+    }
+    
     def showTree = {
         model.treeVisible = true
         resultsPanel.getLayout().show(resultsPanel, "tree")

gui/src/main/groovy/com/muwire/gui/ResultTree.groovy

@@ -86,7 +86,7 @@ class ResultTree extends JTree{
     List<TreePath> selectedFolderPaths() {
         TreePath[] selected = getSelectionPaths()
         if (selected == null)
-            return
+            return Collections.emptyList()
         List<TreePath> rv = []
         for (TreePath path : selected) {
             def obj = path.getLastPathComponent().getUserObject()
@@ -95,5 +95,23 @@ class ResultTree extends JTree{
         }
         rv
     }
+
+    /**
+     * @return true if an unfetched folder has been selected
+     */
+    boolean selectedUnfetchedFolder() {
+        List<TreePath> selected = selectedFolderPaths()
+        if (selected.isEmpty())
+            return false
+        List<?> userObjects = []
+        for (TreePath path : selected) {
+            TreeUtil.getLeafs(path.getLastPathComponent(), userObjects)
+        }
+        for (Object o : userObjects) {
+            if (o == ResultTreeRenderer.PLACEHOLDER)
+                return true
+        }
+        false
+    }
    
 }