Added calculation of participants and average for overview if it is not given

Author: jonastheis

app/src/main/java/de/mygrades/database/dao/Overview.java

@@ -125,6 +125,36 @@ public void setGradeEntryHash(String gradeEntryHash) {
 
     // KEEP METHODS - put your custom methods here
 
+    /**
+     * Gets the amount of an section as int.
+     * @param section The section to get
+     * @return The amount of the section
+     */
+    public int getSection(int section) {
+        switch (section) {
+            case 1:
+                return nullToZero(section1);
+            case 2:
+                return nullToZero(section2);
+            case 3:
+                return nullToZero(section3);
+            case 4:
+                return nullToZero(section4);
+            case 5:
+                return nullToZero(section5);
+        }
+        // if a wrong section is passed return 0
+        return 0;
+    }
+
+    /**
+     * Converts null to zero or returns the given value.
+     * @param n The Integer object
+     * @return 0 if it is null or the value as int
+     */
+    private int nullToZero(Integer n) {
+        return n == null ? 0 : n;
+    }
 
     /**
      * Updates Overview with values from other Overview.

app/src/main/java/de/mygrades/main/core/Transformer.java

@@ -114,6 +114,23 @@ public Overview transformOverview(Double userGrade) throws ParseException {
         overview.setAverage(getDoubleProperty(xmlDocument, OVERVIEW_AVERAGE));
         overview.setUserSection((int) Math.round(userGrade));
 
+        // calculate participants from the sections if it is not given
+        if (overview.getParticipants() == null) {
+            int participants = overview.getSection(1) + overview.getSection(2) + overview.getSection(3)
+                    + overview.getSection(4) + overview.getSection(5);
+            overview.setParticipants(participants);
+        }
+
+        // calculate average from the sections and the participants if it is not given
+        if (overview.getAverage() == null) {
+            if (overview.getParticipants() != null && overview.getParticipants() != 0) {
+                double average = (overview.getSection(1) + overview.getSection(2) * 2 + overview.getSection(3) * 3
+                        + overview.getSection(4) * 4 + overview.getSection(5) * 5) / (double)overview.getParticipants();
+                overview.setAverage(average);
+            }
+
+        }
+
         return overview;
     }