Queue: Keep sorted #1556

app/src/main/java/de/danoeh/antennapod/fragment/QueueFragment.java

@@ -272,6 +272,13 @@ public class QueueFragment extends Fragment {
 
             MenuItemUtils.refreshLockItem(getActivity(), menu);
 
+            // Show Lock Item and Sort Item only if queue is sorted manually
+            boolean sortedManually = UserPreferences.isQueueSortedManually();
+            MenuItem lockItem = menu.findItem(R.id.queue_lock);
+            lockItem.setVisible(sortedManually);
+            MenuItem sortItem = menu.findItem(R.id.queue_sort);
+            sortItem.setVisible(sortedManually);
+
             isUpdatingFeeds = MenuItemUtils.updateRefreshMenuItem(menu, R.id.refresh_item, updateRefreshMenuItemChecker);
         }
     }
@@ -317,37 +324,37 @@ public class QueueFragment extends Fragment {
                     conDialog.createNewDialog().show();
                     return true;
                 case R.id.queue_sort_episode_title_asc:
-                    QueueSorter.sort(getActivity(), QueueSorter.Rule.EPISODE_TITLE_ASC, true);
+                    QueueSorter.sort(QueueSorter.Rule.EPISODE_TITLE_ASC, true);
                     return true;
                 case R.id.queue_sort_episode_title_desc:
-                    QueueSorter.sort(getActivity(), QueueSorter.Rule.EPISODE_TITLE_DESC, true);
+                    QueueSorter.sort(QueueSorter.Rule.EPISODE_TITLE_DESC, true);
                     return true;
                 case R.id.queue_sort_date_asc:
-                    QueueSorter.sort(getActivity(), QueueSorter.Rule.DATE_ASC, true);
+                    QueueSorter.sort(QueueSorter.Rule.DATE_ASC, true);
                     return true;
                 case R.id.queue_sort_date_desc:
-                    QueueSorter.sort(getActivity(), QueueSorter.Rule.DATE_DESC, true);
+                    QueueSorter.sort(QueueSorter.Rule.DATE_DESC, true);
                     return true;
                 case R.id.queue_sort_duration_asc:
-                    QueueSorter.sort(getActivity(), QueueSorter.Rule.DURATION_ASC, true);
+                    QueueSorter.sort(QueueSorter.Rule.DURATION_ASC, true);
                     return true;
                 case R.id.queue_sort_duration_desc:
-                    QueueSorter.sort(getActivity(), QueueSorter.Rule.DURATION_DESC, true);
+                    QueueSorter.sort(QueueSorter.Rule.DURATION_DESC, true);
                     return true;
                 case R.id.queue_sort_feed_title_asc:
-                    QueueSorter.sort(getActivity(), QueueSorter.Rule.FEED_TITLE_ASC, true);
+                    QueueSorter.sort(QueueSorter.Rule.FEED_TITLE_ASC, true);
                     return true;
                 case R.id.queue_sort_feed_title_desc:
-                    QueueSorter.sort(getActivity(), QueueSorter.Rule.FEED_TITLE_DESC, true);
+                    QueueSorter.sort(QueueSorter.Rule.FEED_TITLE_DESC, true);
                     return true;
                 case R.id.queue_sort_random:
-                    QueueSorter.sort(getActivity(), QueueSorter.Rule.RANDOM, true);
+                    QueueSorter.sort(QueueSorter.Rule.RANDOM, true);
                     return true;
                 case R.id.queue_sort_smart_shuffle_asc:
-                    QueueSorter.sort(getActivity(), QueueSorter.Rule.SMART_SHUFFLE_ASC, true);
+                    QueueSorter.sort(QueueSorter.Rule.SMART_SHUFFLE_ASC, true);
                     return true;
                 case R.id.queue_sort_smart_shuffle_desc:
-                    QueueSorter.sort(getActivity(), QueueSorter.Rule.SMART_SHUFFLE_DESC, true);
+                    QueueSorter.sort(QueueSorter.Rule.SMART_SHUFFLE_DESC, true);
                     return true;
                 default:
                     return false;
@@ -661,5 +668,4 @@ public class QueueFragment extends Fragment {
                     }
                 }, error -> Log.e(TAG, Log.getStackTraceString(error)));
     }
-
 }

app/src/main/java/de/danoeh/antennapod/fragment/preferences/UserInterfacePreferencesFragment.java

@@ -11,7 +11,12 @@ import android.widget.ListView;
 import android.widget.Toast;
 import de.danoeh.antennapod.R;
 import de.danoeh.antennapod.activity.MainActivity;
+import de.danoeh.antennapod.core.feed.FeedItem;
 import de.danoeh.antennapod.core.preferences.UserPreferences;
+import de.danoeh.antennapod.core.storage.DBWriter;
+import de.danoeh.antennapod.core.util.Permutor;
+import de.danoeh.antennapod.core.util.QueueSorter;
+
 import org.apache.commons.lang3.ArrayUtils;
 
 import java.util.List;
@@ -89,6 +94,17 @@ public class UserInterfacePreferencesFragment extends PreferenceFragmentCompat {
         if (Build.VERSION.SDK_INT >= 26) {
             findPreference(UserPreferences.PREF_EXPANDED_NOTIFICATION).setVisible(false);
         }
+
+        findPreference(UserPreferences.PREF_QUEUE_SORT_ORDER)
+                .setOnPreferenceChangeListener((preference, newValue) -> {
+                    UserPreferences.QueueSortOrder newSortOrder = UserPreferences.parseQueueSortOrder((String) newValue);
+                    if (newSortOrder != UserPreferences.QueueSortOrder.MANUALLY) {
+                        QueueSorter.Rule sortRule = QueueSorter.queueSortOrder2Rule(newSortOrder);
+                        Permutor<FeedItem> permutor = QueueSorter.getPermutor(sortRule);
+                        DBWriter.reorderQueue(permutor, true);
+                    }
+                    return true;
+                });
     }
 
     private void showDrawerPreferencesDialog() {

app/src/main/java/de/danoeh/antennapod/menuhandler/FeedItemMenuHandler.java

@@ -68,16 +68,17 @@ public class FeedItemMenuHandler {
         }
         boolean hasMedia = selectedItem.getMedia() != null;
         boolean isPlaying = hasMedia && selectedItem.getState() == FeedItem.State.PLAYING;
+        boolean sortedManually = UserPreferences.isQueueSortedManually();
 
         if (!isPlaying) {
             mi.setItemVisibility(R.id.skip_episode_item, false);
         }
 
         boolean isInQueue = selectedItem.isTagged(FeedItem.TAG_QUEUE);
-        if(queueAccess == null || queueAccess.size() == 0 || queueAccess.get(0) == selectedItem.getId()) {
+        if (queueAccess == null || queueAccess.size() == 0 || queueAccess.get(0) == selectedItem.getId() || !sortedManually) {
             mi.setItemVisibility(R.id.move_to_top_item, false);
         }
-        if(queueAccess == null || queueAccess.size() == 0 || queueAccess.get(queueAccess.size()-1) == selectedItem.getId()) {
+        if (queueAccess == null || queueAccess.size() == 0 || queueAccess.get(queueAccess.size()-1) == selectedItem.getId() || !sortedManually) {
             mi.setItemVisibility(R.id.move_to_bottom_item, false);
         }
         if (!isInQueue) {

app/src/main/res/xml/preferences_user_interface.xml

@@ -32,6 +32,14 @@
                 android:summary="@string/pref_nav_drawer_feed_counter_sum"
                 android:defaultValue="0"
                 app:useStockLayout="true"/>
+        <ListPreference
+                android:entryValues="@array/nav_queue_sort_values"
+                android:entries="@array/nav_queue_sort_options"
+                android:title="@string/pref_queue_sort_title"
+                android:key="prefQueueSortOrder"
+                android:summary="@string/pref_queue_sort_sum"
+                android:defaultValue="MANUALLY"
+                app:useStockLayout="true"/>
     </PreferenceCategory>
     <PreferenceCategory android:title="@string/external_elements">
         <SwitchPreference

core/src/main/java/de/danoeh/antennapod/core/preferences/UserPreferences.java

@@ -54,6 +54,7 @@ public class UserPreferences {
     private static final String PREF_SHOW_DOWNLOAD_REPORT = "prefShowDownloadReport";
     public static final String PREF_BACK_BUTTON_BEHAVIOR = "prefBackButtonBehavior";
     private static final String PREF_BACK_BUTTON_GO_TO_PAGE = "prefBackButtonGoToPage";
+    public static final String PREF_QUEUE_SORT_ORDER = "prefQueueSortOrder";
 
     // Queue
     private static final String PREF_QUEUE_ADD_TO_FRONT = "prefQueueAddToFront";
@@ -506,7 +507,8 @@ public class UserPreferences {
     }
 
     public static boolean isQueueLocked() {
-        return prefs.getBoolean(PREF_QUEUE_LOCKED, false);
+        return prefs.getBoolean(PREF_QUEUE_LOCKED, false)
+                || !isQueueSortedManually();
     }
 
     public static void setFastForwardSecs(int secs) {
@@ -894,4 +896,32 @@ public class UserPreferences {
     public static boolean timeRespectsSpeed() {
         return prefs.getBoolean(PREF_TIME_RESPECTS_SPEED, false);
     }
+
+    /**
+     * Supported episode queue sort orders.
+     * Use enum instead of integer to avoid mistakes at later maintenance changes.
+     */
+    public enum QueueSortOrder {
+        MANUALLY, DATE_NEW_OLD, DATE_OLD_NEW, DURATION_SHORT_LONG, DURATION_LONG_SHORT,
+        EPISODE_TITLE_A_Z, EPISODE_TITLE_Z_A, FEED_TITLE_A_Z, FEED_TITLE_Z_A
+    }
+
+    public static QueueSortOrder getQueueSortOrder() {
+        String sortOrderStr = prefs.getString(PREF_QUEUE_SORT_ORDER, "default");
+        return parseQueueSortOrder(sortOrderStr);
+    }
+
+    public static QueueSortOrder parseQueueSortOrder(String value) {
+        try {
+            return QueueSortOrder.valueOf(value);
+        } catch (IllegalArgumentException e) {
+            // default value
+            return QueueSortOrder.MANUALLY;
+        }
+    }
+
+    public static boolean isQueueSortedManually() {
+        QueueSortOrder sortedOrder = getQueueSortOrder();
+        return sortedOrder == QueueSortOrder.MANUALLY;
+    }
 }

core/src/main/java/de/danoeh/antennapod/core/storage/DBWriter.java

@@ -46,6 +46,7 @@ import de.danoeh.antennapod.core.service.playback.PlaybackService;
 import de.danoeh.antennapod.core.util.IntentUtils;
 import de.danoeh.antennapod.core.util.LongList;
 import de.danoeh.antennapod.core.util.Permutor;
+import de.danoeh.antennapod.core.util.QueueSorter;
 import de.danoeh.antennapod.core.util.flattr.FlattrStatus;
 import de.danoeh.antennapod.core.util.flattr.FlattrThing;
 import de.danoeh.antennapod.core.util.flattr.SimpleFlattrThing;
@@ -388,6 +389,7 @@ public class DBWriter {
                         }
                     }
                     if (queueModified) {
+                        applySortOrder(queue, events);
                         adapter.setQueue(queue);
                         for (QueueEvent event : events) {
                             EventBus.getDefault().post(event);
@@ -406,6 +408,29 @@ public class DBWriter {
         });
     }
 
+    /**
+     * Sorts the queue depending on the configured sort order. If manual order is configured, the queue is not modified.
+     *
+     * @param queue  The queue to be sorted.
+     * @param events Replaces the events by a single SORT event if the list has to be sorted automatically.
+     */
+    private static void applySortOrder(List<FeedItem> queue, List<QueueEvent> events) {
+        if (UserPreferences.isQueueSortedManually()) {
+            // automatic sort order is disabled, don't change anything
+            return;
+        }
+
+        // Sort queue by configured sort order
+        UserPreferences.QueueSortOrder sortOrder = UserPreferences.getQueueSortOrder();
+        QueueSorter.Rule sortRule = QueueSorter.queueSortOrder2Rule(sortOrder);
+        Permutor<FeedItem> permutor = QueueSorter.getPermutor(sortRule);
+        permutor.reorder(queue);
+
+        // Replace ADDED events by a single SORTED event
+        events.clear();
+        events.add(QueueEvent.sorted(queue));
+    }
+
     /**
      * Removes all FeedItem objects from the queue.
      *
@@ -964,31 +989,8 @@ public class DBWriter {
     }
 
     /**
-     * Sort the FeedItems in the queue with the given Comparator.
+     * Sort the FeedItems in the queue with the given Permutor.
-     * @param comparator      FeedItem comparator
+     *
-     * @param broadcastUpdate true if this operation should trigger a QueueUpdateBroadcast. This option should be set to
-     */
-    public static Future<?> sortQueue(final Comparator<FeedItem> comparator, final boolean broadcastUpdate) {
-        return dbExec.submit(() -> {
-            final PodDBAdapter adapter = PodDBAdapter.getInstance();
-            adapter.open();
-            final List<FeedItem> queue = DBReader.getQueue(adapter);
-
-            if (queue != null) {
-                Collections.sort(queue, comparator);
-                adapter.setQueue(queue);
-                if (broadcastUpdate) {
-                    EventBus.getDefault().post(QueueEvent.sorted(queue));
-                }
-            } else {
-                Log.e(TAG, "sortQueue: Could not load queue");
-            }
-            adapter.close();
-        });
-    }
-
-    /**
-     * Similar to sortQueue, but allows more complex reordering by providing whole-queue context.
      * @param permutor        Encapsulates whole-Queue reordering logic.
      * @param broadcastUpdate <code>true</code> if this operation should trigger a
      *                        QueueUpdateBroadcast. This option should be set to <code>false</code>

core/src/main/java/de/danoeh/antennapod/core/util/QueueSorter.java

@@ -1,7 +1,5 @@
 package de.danoeh.antennapod.core.util;
 
-import android.content.Context;
-
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.Comparator;
@@ -11,6 +9,7 @@ import java.util.Map;
 
 import de.danoeh.antennapod.core.feed.FeedItem;
 import de.danoeh.antennapod.core.feed.FeedMedia;
+import de.danoeh.antennapod.core.preferences.UserPreferences;
 import de.danoeh.antennapod.core.storage.DBWriter;
 
 /**
@@ -31,7 +30,30 @@ public class QueueSorter {
         SMART_SHUFFLE_DESC
     }
 
-    public static void sort(final Context context, final Rule rule, final boolean broadcastUpdate) {
+    /**
+     * Sorts the queue by the given rule and sends a broadcast update.
+     *
+     * @param rule Sort rule.
+     * @param broadcastUpdate Send broadcast update?
+     */
+    public static void sort(Rule rule, boolean broadcastUpdate) {
+        Permutor<FeedItem> permutor = getPermutor(rule);
+        if (permutor != null) {
+            DBWriter.reorderQueue(permutor, broadcastUpdate);
+        }
+    }
+
+    /**
+     * Returns a Permutor that sorts a list appropriate to the given sort rule.
+     *
+     * @param rule Sort rule.
+     * @return Permutor that sorts a list appropriate to the given sort rule. <code>null</code> if the rule is unknown or <code>null</code>.
+     */
+    public static Permutor<FeedItem> getPermutor(Rule rule) {
+        if (rule == null) {
+            return null;
+        }
+
         Comparator<FeedItem> comparator = null;
         Permutor<FeedItem> permutor = null;
 
@@ -86,13 +108,44 @@ public class QueueSorter {
             case SMART_SHUFFLE_DESC:
                 permutor = (queue) -> smartShuffle(queue, false);
                 break;
-            default:
         }
 
         if (comparator != null) {
-            DBWriter.sortQueue(comparator, broadcastUpdate);
+            final Comparator<FeedItem> comparator2 = comparator;
-        } else if (permutor != null) {
+            permutor = (queue) -> Collections.sort(queue, comparator2);
-            DBWriter.reorderQueue(permutor, broadcastUpdate);
+        }
+        return permutor;
+    }
+
+    /**
+     * Converts a QueueSortOrder value to its corresponding Rule value.
+     *
+     * @param sortOrder Sort order.
+     * @return Rule value corresponding to the given sort order. <code>null</code> if the sort order is unknown or <code>null</code>.
+     */
+    public static Rule queueSortOrder2Rule(UserPreferences.QueueSortOrder sortOrder) {
+        if (sortOrder == null) {
+            return null;
+        }
+        switch (sortOrder) {
+            case DATE_NEW_OLD:
+                return QueueSorter.Rule.DATE_DESC;
+            case DATE_OLD_NEW:
+                return QueueSorter.Rule.DATE_ASC;
+            case DURATION_SHORT_LONG:
+                return QueueSorter.Rule.DURATION_ASC;
+            case DURATION_LONG_SHORT:
+                return QueueSorter.Rule.DURATION_DESC;
+            case EPISODE_TITLE_A_Z:
+                return QueueSorter.Rule.EPISODE_TITLE_ASC;
+            case EPISODE_TITLE_Z_A:
+                return QueueSorter.Rule.EPISODE_TITLE_DESC;
+            case FEED_TITLE_A_Z:
+                return QueueSorter.Rule.FEED_TITLE_ASC;
+            case FEED_TITLE_Z_A:
+                return QueueSorter.Rule.FEED_TITLE_DESC;
+            default:
+                return null;
         }
     }
 

core/src/main/res/values-de/strings.xml

@@ -285,6 +285,8 @@
   <string name="ascending">Aufsteigend</string>
   <string name="descending">Absteigend</string>
   <string name="clear_queue_confirmation_msg">Bitte bestätige, dass ALLE Episoden aus der Abspielliste entfernt werden sollen</string>
+  <string name="sort_new_to_old">Neu bis alt</string>
+  <string name="sort_old_to_new">Alt bis neu</string>
   <!--Flattr-->
   <string name="flattr_auth_label">Flattr Anmeldung</string>
   <string name="flattr_auth_explanation">Drücke den Button unten, um den Authentifizierungsprozess zu starten. Du wirst zur Flattr-Anmeldeseite weitergeleitet. Hier wirst du gefragt, AntennaPod die Erlaubnis zu geben, Dinge zu flattrn. Nachdem du die Erlaubnis erteilt hast, kehrst du automatisch zu diesem Bildschirm zurück.</string>
@@ -414,6 +416,8 @@
   <string name="pref_nav_drawer_feed_order_sum">Ändere die Reihenfolge deiner Abonnements</string>
   <string name="pref_nav_drawer_feed_counter_title">Abonnement-Zähler einstellen</string>
   <string name="pref_nav_drawer_feed_counter_sum">Ändere die durch den Abonnementszähler angezeigten Informationen. Betrifft auch die Sortierung der Abonnements wenn \"Reihenfolge der Abonnements\" auf \"Zähler\" gesetzt ist.</string>
+  <string name="pref_queue_sort_title">Sortierung der Abspielliste einstellen</string>
+  <string name="pref_queue_sort_sum">Ändere die Sortierreihenfolge der Episoden in der Abspielliste.</string>
   <string name="pref_set_theme_sum">Ändere das Aussehen von AntennaPod.</string>
   <string name="pref_automatic_download_title">Automatisches Herunterladen</string>
   <string name="pref_automatic_download_sum">Konfiguriere das automatische Herunterladen von Episoden.</string>
@@ -686,6 +690,11 @@
   <string name="sort_date_old_new">Datum (alt \u2192 neu)</string>
   <string name="sort_duration_short_long">Dauer (kurz \u2192 lang)</string>
   <string name="sort_duration_long_short">Dauer (lang \u2192 kurz)</string>
+  <string name="sort_episode_title_a_z">Episodentitel (A \u2192 Z)</string>
+  <string name="sort_episode_title_z_a">Episodentitel (Z \u2192 A)</string>
+  <string name="sort_feed_title_a_z">Podcasttitel (A \u2192 Z)</string>
+  <string name="sort_feed_title_z_a">Podcasttitel (Z \u2192 A)</string>
+  <string name="sort_manually">Manuell</string>
   <!--Rating dialog-->
   <string name="rating_title">Gefällt dir AntennaPod?</string>
   <string name="rating_message">Wir würden uns freuen, wenn du dir kurz die Zeit nimmst, AntennaPod zu bewerten.</string>

core/src/main/res/values/arrays.xml

@@ -187,6 +187,29 @@
         <item>3</item>
     </string-array>
 
+    <string-array name="nav_queue_sort_options">
+        <item>@string/sort_manually</item>
+        <item>@string/sort_date_new_old</item>
+        <item>@string/sort_date_old_new</item>
+        <item>@string/sort_duration_short_long</item>
+        <item>@string/sort_duration_long_short</item>
+        <item>@string/sort_episode_title_a_z</item>
+        <item>@string/sort_episode_title_z_a</item>
+        <item>@string/sort_feed_title_a_z</item>
+        <item>@string/sort_feed_title_z_a</item>
+    </string-array>
+    <string-array name="nav_queue_sort_values">
+        <item>MANUALLY</item>
+        <item>DATE_NEW_OLD</item>
+        <item>DATE_OLD_NEW</item>
+        <item>DURATION_SHORT_LONG</item>
+        <item>DURATION_LONG_SHORT</item>
+        <item>EPISODE_TITLE_A_Z</item>
+        <item>EPISODE_TITLE_Z_A</item>
+        <item>FEED_TITLE_A_Z</item>
+        <item>FEED_TITLE_Z_A</item>
+    </string-array>
+
     <string-array name="nav_drawer_feed_counter_options">
         <item>@string/drawer_feed_counter_new_unplayed</item>
         <item>@string/drawer_feed_counter_new</item>

core/src/main/res/values/strings.xml

@@ -438,6 +438,8 @@
     <string name="pref_nav_drawer_feed_order_sum">Change the order of your subscriptions</string>
     <string name="pref_nav_drawer_feed_counter_title">Set Subscription Counter</string>
     <string name="pref_nav_drawer_feed_counter_sum">Change the information displayed by the subscription counter. Also affects the sorting of subscriptions if \'Subscription Order\' is set to \'Counter\'.</string>
+    <string name="pref_queue_sort_title">Set Queue Sort Order</string>
+    <string name="pref_queue_sort_sum">Change the sort order of the episodes in the queue.</string>
     <string name="pref_set_theme_sum">Change the appearance of AntennaPod.</string>
     <string name="pref_automatic_download_title">Automatic Download</string>
     <string name="pref_automatic_download_sum">Configure the automatic download of episodes.</string>
@@ -735,6 +737,11 @@
     <string name="sort_date_old_new">Date (Old \u2192 New)</string>
     <string name="sort_duration_short_long">Duration (Short \u2192 Long)</string>
     <string name="sort_duration_long_short">Duration (Long \u2192 Short)</string>
+    <string name="sort_episode_title_a_z">Episode title (A \u2192 Z)</string>
+    <string name="sort_episode_title_z_a">Episode title (Z \u2192 A)</string>
+    <string name="sort_feed_title_a_z">Podcast title (A \u2192 Z)</string>
+    <string name="sort_feed_title_z_a">Podcast title (Z \u2192 A)</string>
+    <string name="sort_manually">Manually</string>
 
     <!-- Rating dialog -->
     <string name="rating_title">Like AntennaPod?</string>

core/src/test/java/android/text/TextUtils.java

@@ -29,4 +29,13 @@ public class TextUtils {
         return false;
     }
 
+    /**
+     * Returns <code>true</code> if the string is <code>null</code> or has zero length.
+     *
+     * @param str The string to be examined, can be <code>null</code>.
+     * @return <code>true</code> if the string is <code>null</code> or has zero length.
+     */
+    public static boolean isEmpty(CharSequence str) {
+        return str == null || str.length() == 0;
+    }
 }

core/src/test/java/de/danoeh/antennapod/core/util/QueueSorterTest.java

@@ -0,0 +1,156 @@
+package de.danoeh.antennapod.core.util;
+
+import org.junit.Test;
+
+import java.util.ArrayList;
+import java.util.Calendar;
+import java.util.List;
+
+import de.danoeh.antennapod.core.feed.Feed;
+import de.danoeh.antennapod.core.feed.FeedItem;
+import de.danoeh.antennapod.core.feed.FeedMedia;
+
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.assertNull;
+
+/**
+ * Test class for QueueSorter.
+ */
+public class QueueSorterTest {
+
+    @Test
+    public void testPermutorForRule_null() {
+        assertNull(QueueSorter.getPermutor(null));
+    }
+
+    @Test
+    public void testPermutorForRule_EPISODE_TITLE_ASC() {
+        Permutor<FeedItem> permutor = QueueSorter.getPermutor(QueueSorter.Rule.EPISODE_TITLE_ASC);
+
+        List<FeedItem> itemList = getTestList();
+        assertTrue(checkIdOrder(itemList, 1, 3, 2)); // before sorting
+        permutor.reorder(itemList);
+        assertTrue(checkIdOrder(itemList, 1, 2, 3)); // after sorting
+    }
+
+    @Test
+    public void testPermutorForRule_EPISODE_TITLE_DESC() {
+        Permutor<FeedItem> permutor = QueueSorter.getPermutor(QueueSorter.Rule.EPISODE_TITLE_DESC);
+
+        List<FeedItem> itemList = getTestList();
+        assertTrue(checkIdOrder(itemList, 1, 3, 2)); // before sorting
+        permutor.reorder(itemList);
+        assertTrue(checkIdOrder(itemList, 3, 2, 1)); // after sorting
+    }
+
+    @Test
+    public void testPermutorForRule_DATE_ASC() {
+        Permutor<FeedItem> permutor = QueueSorter.getPermutor(QueueSorter.Rule.DATE_ASC);
+
+        List<FeedItem> itemList = getTestList();
+        assertTrue(checkIdOrder(itemList, 1, 3, 2)); // before sorting
+        permutor.reorder(itemList);
+        assertTrue(checkIdOrder(itemList, 1, 2, 3)); // after sorting
+    }
+
+    @Test
+    public void testPermutorForRule_DATE_DESC() {
+        Permutor<FeedItem> permutor = QueueSorter.getPermutor(QueueSorter.Rule.DATE_DESC);
+
+        List<FeedItem> itemList = getTestList();
+        assertTrue(checkIdOrder(itemList, 1, 3, 2)); // before sorting
+        permutor.reorder(itemList);
+        assertTrue(checkIdOrder(itemList, 3, 2, 1)); // after sorting
+    }
+
+    @Test
+    public void testPermutorForRule_DURATION_ASC() {
+        Permutor<FeedItem> permutor = QueueSorter.getPermutor(QueueSorter.Rule.DURATION_ASC);
+
+        List<FeedItem> itemList = getTestList();
+        assertTrue(checkIdOrder(itemList, 1, 3, 2)); // before sorting
+        permutor.reorder(itemList);
+        assertTrue(checkIdOrder(itemList, 1, 2, 3)); // after sorting
+    }
+
+    @Test
+    public void testPermutorForRule_DURATION_DESC() {
+        Permutor<FeedItem> permutor = QueueSorter.getPermutor(QueueSorter.Rule.DURATION_DESC);
+
+        List<FeedItem> itemList = getTestList();
+        assertTrue(checkIdOrder(itemList, 1, 3, 2)); // before sorting
+        permutor.reorder(itemList);
+        assertTrue(checkIdOrder(itemList, 3, 2, 1)); // after sorting
+    }
+
+    @Test
+    public void testPermutorForRule_FEED_TITLE_ASC() {
+        Permutor<FeedItem> permutor = QueueSorter.getPermutor(QueueSorter.Rule.FEED_TITLE_ASC);
+
+        List<FeedItem> itemList = getTestList();
+        assertTrue(checkIdOrder(itemList, 1, 3, 2)); // before sorting
+        permutor.reorder(itemList);
+        assertTrue(checkIdOrder(itemList, 1, 2, 3)); // after sorting
+    }
+
+    @Test
+    public void testPermutorForRule_FEED_TITLE_DESC() {
+        Permutor<FeedItem> permutor = QueueSorter.getPermutor(QueueSorter.Rule.FEED_TITLE_DESC);
+
+        List<FeedItem> itemList = getTestList();
+        assertTrue(checkIdOrder(itemList, 1, 3, 2)); // before sorting
+        permutor.reorder(itemList);
+        assertTrue(checkIdOrder(itemList, 3, 2, 1)); // after sorting
+    }
+
+    /**
+     * Generates a list with test data.
+     */
+    private List<FeedItem> getTestList() {
+        List<FeedItem> itemList = new ArrayList<>();
+
+        Calendar calendar = Calendar.getInstance();
+        calendar.set(2019, 0, 1);  // January 1st
+        Feed feed1 = new Feed(null, null, "Feed title 1");
+        FeedItem feedItem1 = new FeedItem(1, "Title 1", null, null, calendar.getTime(), 0, feed1);
+        FeedMedia feedMedia1 = new FeedMedia(0, feedItem1, 1000, 0, 0, null, null, null, true, null, 0, 0);
+        feedItem1.setMedia(feedMedia1);
+        itemList.add(feedItem1);
+
+        calendar.set(2019, 2, 1);  // March 1st
+        Feed feed2 = new Feed(null, null, "Feed title 3");
+        FeedItem feedItem2 = new FeedItem(3, "Title 3", null, null, calendar.getTime(), 0, feed2);
+        FeedMedia feedMedia2 = new FeedMedia(0, feedItem2, 3000, 0, 0, null, null, null, true, null, 0, 0);
+        feedItem2.setMedia(feedMedia2);
+        itemList.add(feedItem2);
+
+        calendar.set(2019, 1, 1);  // February 1st
+        Feed feed3 = new Feed(null, null, "Feed title 2");
+        FeedItem feedItem3 = new FeedItem(2, "Title 2", null, null, calendar.getTime(), 0, feed3);
+        FeedMedia feedMedia3 = new FeedMedia(0, feedItem3, 2000, 0, 0, null, null, null, true, null, 0, 0);
+        feedItem3.setMedia(feedMedia3);
+        itemList.add(feedItem3);
+
+        return itemList;
+    }
+
+    /**
+     * Checks if both lists have the same size and the same ID order.
+     *
+     * @param itemList Item list.
+     * @param ids      List of IDs.
+     * @return <code>true</code> if both lists have the same size and the same ID order.
+     */
+    private boolean checkIdOrder(List<FeedItem> itemList, long... ids) {
+        if (itemList.size() != ids.length) {
+            return false;
+        }
+
+        for (int i = 0; i < ids.length; i++) {
+            if (itemList.get(i).getId() != ids[i]) {
+                return false;
+            }
+        }
+        return true;
+    }
+}