Change the logic of checking changes in service

Now service tracks changes not by comparing old and new update time,
but by total sum of all scores.

app/src/main/java/ua/samosfator/moduleok/notification/ScoreCheckerService.java

@@ -4,7 +4,6 @@
 import android.content.Intent;
 import android.os.IBinder;
 import android.util.Log;
-import android.widget.Toast;
 
 import java.util.Timer;
 import java.util.TimerTask;
@@ -23,7 +22,7 @@ public class ScoreCheckerService extends Service {
     public static int pendingModulesCount = NearbyModules.getCount();
 
     private Timer timer = new Timer("timer");
-    private TimerTask updateTimeTask = new UpdateTimeTask();
+    private TimerTask scoresChangedTask = new ScoresChangedTask();
     private TimerTask moduleDatesUpdateTask = new ModuleDatesUpdateTask();
 
     public ScoreCheckerService() {
@@ -70,22 +69,28 @@ public void onEvent(InternetConnectionAbsent event) {
     }
 
     private void startServiceTimer() {
+        scheduleModuleDatesUpdateTask();
+        scheduleScoresChangedTask();
+    }
+
+    private void scheduleModuleDatesUpdateTask() {
         moduleDatesUpdateTask = new ModuleDatesUpdateTask();
         timer.schedule(moduleDatesUpdateTask, 200, TimeUnit.HOURS.toMillis(12));
+    }
 
-        updateTimeTask = new UpdateTimeTask();
+    private void scheduleScoresChangedTask() {
+        scoresChangedTask = new ScoresChangedTask();
         ModuleDatesUpdateTask.updatePendingModulesCount();
         if (pendingModulesCount > 0) {
-            timer.schedule(updateTimeTask, 0, TimeUnit.HOURS.toMillis(2));
-
             Log.d(TAG, "" + pendingModulesCount + " modules in the near 2 days");
+            timer.schedule(scoresChangedTask, 0, TimeUnit.HOURS.toMillis(2));
         } else {
             Log.d(TAG, "No modules dates in the near 2 days");
         }
     }
 
     private void stopServiceTimer() {
         moduleDatesUpdateTask.cancel();
-        updateTimeTask.cancel();
+        scoresChangedTask.cancel();
     }
 }

app/src/main/java/ua/samosfator/moduleok/notification/ScoresChangedTask.java

@@ -0,0 +1,44 @@
+package ua.samosfator.moduleok.notification;
+
+import java.util.List;
+import java.util.TimerTask;
+
+import java8.util.stream.StreamSupport;
+import ua.samosfator.moduleok.SessionIdExpiredException;
+import ua.samosfator.moduleok.StudentKeeper;
+import ua.samosfator.moduleok.parser.Subject;
+
+public class ScoresChangedTask extends TimerTask {
+    @Override
+    public void run() {
+        if (areScoresChanged()) {
+            ScoreCheckerNotification.sendNotification();
+        }
+    }
+
+    private boolean areScoresChanged() {
+        List<Subject> oldSubjects = getSubjects();
+        try {
+            StudentKeeper.refreshStudent();
+        } catch (SessionIdExpiredException ignored) {
+        }
+        List<Subject> newSubjects = getSubjects();
+
+        return getTotalSumAllScores(oldSubjects) != getTotalSumAllScores(newSubjects);
+    }
+
+    private int getTotalSumAllScores(List<Subject> subjects) {
+        final int[] oldTotalScore = {0};
+        StreamSupport.parallelStream(subjects)
+                .map(subject -> StreamSupport.parallelStream(subject.getModules()))
+                .map(modulesStream -> modulesStream.map(module -> oldTotalScore[0] += module.getScore()));
+        return oldTotalScore[0];
+    }
+
+    private List<Subject> getSubjects() {
+        return StudentKeeper.getCurrentStudent()
+                .getSemesters()
+                .get(StudentKeeper.getCurrentSemesterIndex())
+                .getSubjects();
+    }
+}