Add support for downloading tracks to a permanent location.

src/main/java/moe/nekojimi/chords/Downloader.java

@@ -60,7 +60,8 @@ public class Downloader extends QueueThing<TrackRequest, Track>
 //    private Consumer<Track> next;
     private BiConsumer<TrackRequest, Exception> messageHandler;
 
-    private File downloadDir = null;
+    private File temporaryDownloadDir = null;
+    private File permanentDownloadDir = null;
 
     private int trackNumber = 1;
 
@@ -313,9 +314,24 @@ public class Downloader extends QueueThing<TrackRequest, Track>
 
     private File getDownloadDir() throws IOException
     {
-        if (downloadDir == null || !downloadDir.exists() || !downloadDir.canWrite())
-            downloadDir = Files.createTempDirectory("chords").toFile();
-        return downloadDir;
+        return getDownloadDir(false);
+    }
+
+    private File getDownloadDir(boolean permanent) throws IOException
+    {
+        if (permanent)
+        {
+            if (permanentDownloadDir == null)
+                permanentDownloadDir = new File("tracks");
+            if (!permanentDownloadDir.exists())
+                Files.createDirectory(permanentDownloadDir.toPath());
+            return permanentDownloadDir;
+        } else
+        {
+            if (temporaryDownloadDir == null || !temporaryDownloadDir.exists() || !temporaryDownloadDir.canWrite())
+                temporaryDownloadDir = Files.createTempDirectory("chords").toFile();
+            return temporaryDownloadDir;
+        }
     }
 
     private Track getTrackFromRequest(TrackRequest request, int idx)
@@ -325,6 +341,7 @@ public class Downloader extends QueueThing<TrackRequest, Track>
         {
             Track track = new Track(request);
             track.setNumber(trackNumber);
+            track.setKept(request.isKeepTracks());
             trackNumber++;
             request.addTrack(track);
         }
@@ -368,7 +385,7 @@ public class Downloader extends QueueThing<TrackRequest, Track>
                 cmd.add("-");
             } else
             {
-                cmd.add("-o " + getDownloadDir().getAbsolutePath() + "/%(title)s.%(ext)s");
+                cmd.add("-o " + getDownloadDir(false).getAbsolutePath() + "/%(title)s.%(ext)s");
             }
             cmd.add(request.getUrl().toString());