From 0b29608d5977cd94e5feaf0a33fd21a7f9ff8930 Mon Sep 17 00:00:00 2001
From: Valentina Kiryushkina <valentina.kiryushkina@jetbrains.com>
Date: Wed, 11 Jan 2017 14:29:31 +0300
Subject: [PATCH] EDU-810 Friendly message in case we got no recommendations
 for the adaptive course

---
 .../src/com/jetbrains/edu/learning/StudyUtils.java    |  4 ++++
 .../courseGeneration/StudyProjectGenerator.java       |  6 +++++-
 .../edu/learning/stepic/EduStepicConnector.java       | 11 ++++-------
 3 files changed, 13 insertions(+), 8 deletions(-)

diff --git a/python/educational-core/student/src/com/jetbrains/edu/learning/StudyUtils.java b/python/educational-core/student/src/com/jetbrains/edu/learning/StudyUtils.java
index feba895970a2..e62040a37aea 100644
--- a/python/educational-core/student/src/com/jetbrains/edu/learning/StudyUtils.java
+++ b/python/educational-core/student/src/com/jetbrains/edu/learning/StudyUtils.java
@@ -848,4 +848,8 @@ public class StudyUtils {
     final int endOffset = startOffset + length + delta;
     return Pair.create(startOffset, endOffset);
   }
+  
+  public static boolean isCourseValid(@Nullable Course course) {
+    return course != null && !(course.isAdaptive() && course.getLessons().isEmpty());
+  }
 }
diff --git a/python/educational-core/student/src/com/jetbrains/edu/learning/courseGeneration/StudyProjectGenerator.java b/python/educational-core/student/src/com/jetbrains/edu/learning/courseGeneration/StudyProjectGenerator.java
index 49470e5e15e3..67b7996ba098 100644
--- a/python/educational-core/student/src/com/jetbrains/edu/learning/courseGeneration/StudyProjectGenerator.java
+++ b/python/educational-core/student/src/com/jetbrains/edu/learning/courseGeneration/StudyProjectGenerator.java
@@ -93,6 +93,10 @@ public class StudyProjectGenerator {
       Messages.showWarningDialog("Some problems occurred while creating the course", "Error in Course Creation");
       return;
     }
+    else if (course.isAdaptive() && course.getLessons().isEmpty()) {
+      Messages.showWarningDialog("There is no recommended tasks for this adaptive course", "Error in Course Creation");
+      return;
+    }
     final File courseDirectory = StudyUtils.getCourseDirectory(course);
     StudyTaskManager.getInstance(project).setCourse(course);
     ApplicationManager.getApplication().runWriteAction(() -> {
@@ -135,7 +139,7 @@ public class StudyProjectGenerator {
       ProgressManager.getInstance().getProgressIndicator().setIndeterminate(true);
       return execCancelable(() -> {
         final Course course = EduStepicConnector.getCourse(project, mySelectedCourseInfo);
-        if (course != null) {
+        if (StudyUtils.isCourseValid(course)) {
           flushCourse(course);
           course.initCourse(false);
         }
diff --git a/python/educational-core/student/src/com/jetbrains/edu/learning/stepic/EduStepicConnector.java b/python/educational-core/student/src/com/jetbrains/edu/learning/stepic/EduStepicConnector.java
index 01e83454cb6e..680bab03cfff 100644
--- a/python/educational-core/student/src/com/jetbrains/edu/learning/stepic/EduStepicConnector.java
+++ b/python/educational-core/student/src/com/jetbrains/edu/learning/stepic/EduStepicConnector.java
@@ -212,19 +212,16 @@ public class EduStepicConnector {
       }
     }
     else {
-      final Lesson lesson = new Lesson();
       course.setName(info.getName());
       //TODO: more specific name?
-      lesson.setName("Adaptive");
-      course.addLesson(lesson);
       final Task recommendation = EduAdaptiveStepicConnector.getNextRecommendation(project, course);
       if (recommendation != null) {
+        final Lesson lesson = new Lesson();
+        lesson.setName("Adaptive");
+        course.addLesson(lesson);
         lesson.addTask(recommendation);
-        return course;
-      }
-      else {
-        return null;
       }
+      return course;
     }
     return null;
   }