1 files changed, 65 insertions, 0 deletions
diff --git a/python/edu/learn-python/src/com/jetbrains/python/edu/actions/StudyWindowNavigationAction.java b/python/edu/learn-python/src/com/jetbrains/python/edu/actions/StudyWindowNavigationAction.java
new file mode 100644
index 000000000000..8c6b90221555
--- /dev/null
+++ b/python/edu/learn-python/src/com/jetbrains/python/edu/actions/StudyWindowNavigationAction.java
@@ -0,0 +1,65 @@
+package com.jetbrains.python.edu.actions;
+
+import com.intellij.openapi.actionSystem.AnActionEvent;
+import com.intellij.openapi.editor.Editor;
+import com.intellij.openapi.fileEditor.FileDocumentManager;
+import com.intellij.openapi.project.DumbAwareAction;
+import com.intellij.openapi.project.Project;
+import com.intellij.openapi.vfs.VirtualFile;
+import com.jetbrains.python.edu.StudyTaskManager;
+import com.jetbrains.python.edu.StudyUtils;
+import com.jetbrains.python.edu.course.TaskFile;
+import com.jetbrains.python.edu.course.TaskWindow;
+import com.jetbrains.python.edu.editor.StudyEditor;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import javax.swing.*;
+
+abstract public class StudyWindowNavigationAction extends DumbAwareAction {
+
+  public StudyWindowNavigationAction(String actionId, String description, Icon icon) {
+    super(actionId, description, icon);
+  }
+
+  public void navigateWindow(@NotNull final Project project) {
+      Editor selectedEditor = StudyEditor.getSelectedEditor(project);
+      if (selectedEditor != null) {
+        FileDocumentManager fileDocumentManager = FileDocumentManager.getInstance();
+        VirtualFile openedFile = fileDocumentManager.getFile(selectedEditor.getDocument());
+        if (openedFile != null) {
+          StudyTaskManager taskManager = StudyTaskManager.getInstance(project);
+          TaskFile selectedTaskFile = taskManager.getTaskFile(openedFile);
+          if (selectedTaskFile != null) {
+            TaskWindow selectedTaskWindow = selectedTaskFile.getSelectedTaskWindow();
+            if (selectedTaskWindow == null) {
+              return;
+            }
+            TaskWindow nextTaskWindow = getNextTaskWindow(selectedTaskWindow);
+            if (nextTaskWindow == null) {
+              return;
+            }
+            nextTaskWindow.draw(selectedEditor, true, true);
+            selectedTaskFile.setSelectedTaskWindow(nextTaskWindow);
+            }
+          }
+        }
+      }
+
+  @Nullable
+  protected abstract TaskWindow getNextTaskWindow(@NotNull final TaskWindow window);
+
+  @Override
+  public void actionPerformed(AnActionEvent e) {
+    Project project = e.getProject();
+    if (project == null) {
+      return;
+    }
+    navigateWindow(project);
+  }
+
+  @Override
+  public void update(AnActionEvent e) {
+    StudyUtils.updateAction(e);
+  }
+}