wip on file preview

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

@@ -204,6 +204,16 @@ class MainFrameController {
         downloader.pause()
         core.eventBus.publish(new UIDownloadPausedEvent())
     }
+    
+    @ControllerAction
+    void preview() {
+        def downloader = model.downloads[selectedDownload()].downloader
+        File previewFile = downloader.generatePreview()
+        if (previewFile != null)
+            Desktop.getDesktop().open(previewFile)
+        else
+            JOptionPane.showMessageDialog(null, "Failed to generate preview", "Failed to generate preveiw", JOptionPane.ERROR_MESSAGE)
+    }
 
     @ControllerAction
     void clear() {

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

@@ -216,6 +216,7 @@ class MainFrameView {
                                     button(text: "Pause", enabled : bind {model.pauseButtonEnabled}, pauseAction)
                                     button(text: bind { model.resumeButtonText }, enabled : bind {model.retryButtonEnabled}, resumeAction)
                                     button(text: "Cancel", enabled : bind {model.cancelButtonEnabled }, cancelAction)
+                                    button(text: "Preview", previewAction)
                                     button(text: "Clear Done", enabled : bind {model.clearButtonEnabled}, clearAction)
                                 }
                             }