Fix segfault due to insufficient jukebox state validation.

core/include/area_data.h

@@ -321,6 +321,13 @@ class AreaData : public QObject
      */
     bool isjukeboxEnabled() const;
 
+    /**
+     * @brief Returns the amount of songs pending in the Jukebox queue.
+     *
+     * @return Remaining entries of the queue as int.
+     */
+    int getJukeboxQueueSize() const;
+
     /**
      * @brief Locks the area, setting it to LOCKED.
      */

core/src/area_data.cpp

@@ -160,6 +160,11 @@ bool AreaData::isjukeboxEnabled() const
     return m_jukebox;
 }
 
+int AreaData::getJukeboxQueueSize() const
+{
+    return m_jukebox_queue.size();
+}
+
 void AreaData::lock()
 {
     m_locked = LockStatus::LOCKED;

core/src/commands/music.cpp

@@ -218,6 +218,17 @@ void AOClient::cmdJukeboxSkip(int argc, QStringList argv)
     if (!m_showname.isEmpty()) {
         l_name = m_showname;
     }
-    server->getAreaById(m_current_area)->switchJukeboxSong();
+
+    AreaData *l_area = server->getAreaById(m_current_area);
+
+    if (l_area->isjukeboxEnabled()) {
+        if (l_area->getJukeboxQueueSize() >= 1) {
+            l_area->switchJukeboxSong();
             sendServerMessageArea(l_name + " has forced a skip. Playing the next available song.");
+            return;
+        }
+        sendServerMessage("Unable to skip song. Jukebox is currently empty.");
+        return;
+    }
+    sendServerMessage("Unable to skip song. The jukebox is not running.");
 }