1 files changed, 99 insertions, 0 deletions
diff --git a/subsonic-main/src/main/java/net/sourceforge/subsonic/domain/MediaFileComparator.java b/subsonic-main/src/main/java/net/sourceforge/subsonic/domain/MediaFileComparator.java
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+++ b/subsonic-main/src/main/java/net/sourceforge/subsonic/domain/MediaFileComparator.java
@@ -0,0 +1,99 @@
+/*
+ This file is part of Subsonic.
+
+ Subsonic is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ Subsonic is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with Subsonic.  If not, see <http://www.gnu.org/licenses/>.
+
+ Copyright 2009 (C) Sindre Mehus
+ */
+package net.sourceforge.subsonic.domain;
+
+import java.util.Comparator;
+
+import static net.sourceforge.subsonic.domain.MediaFile.MediaType.DIRECTORY;
+
+/**
+ * Comparator for sorting media files.
+ */
+public class MediaFileComparator implements Comparator<MediaFile> {
+
+    private final boolean sortAlbumsByYear;
+
+    public MediaFileComparator(boolean sortAlbumsByYear) {
+        this.sortAlbumsByYear = sortAlbumsByYear;
+    }
+
+    public int compare(MediaFile a, MediaFile b) {
+
+        // Directories before files.
+        if (a.isFile() && b.isDirectory()) {
+            return 1;
+        }
+        if (a.isDirectory() && b.isFile()) {
+            return -1;
+        }
+
+        // Non-album directories before album directories.
+        if (a.isAlbum() && b.getMediaType() == DIRECTORY) {
+            return 1;
+        }
+        if (a.getMediaType() == DIRECTORY && b.isAlbum()) {
+            return -1;
+        }
+
+        // Sort albums by year
+        if (sortAlbumsByYear && a.isAlbum() && b.isAlbum()) {
+            int i = nullSafeCompare(a.getYear(), b.getYear(), false);
+            if (i != 0) {
+                return i;
+            }
+        }
+
+        if (a.isDirectory() && b.isDirectory()) {
+            return a.getName().compareToIgnoreCase(b.getName());
+        }
+
+        // Compare by disc and track numbers, if present.
+        Integer trackA = getSortableDiscAndTrackNumber(a);
+        Integer trackB = getSortableDiscAndTrackNumber(b);
+        int i = nullSafeCompare(trackA, trackB, false);
+        if (i != 0) {
+            return i;
+        }
+
+        return a.getName().compareToIgnoreCase(b.getName());
+    }
+
+    private <T extends Comparable<T>>  int nullSafeCompare(T a, T b, boolean nullIsSmaller) {
+        if (a == null && b == null) {
+            return 0;
+        }
+        if (a == null) {
+            return nullIsSmaller ? -1 : 1;
+        }
+        if (b == null) {
+            return nullIsSmaller ? 1 : -1;
+        }
+        return a.compareTo(b);
+    }
+
+    private Integer getSortableDiscAndTrackNumber(MediaFile file) {
+        if (file.getTrackNumber() == null) {
+            return null;
+        }
+
+        int discNumber = file.getDiscNumber() == null ? 1 : file.getDiscNumber();
+        return discNumber * 1000 + file.getTrackNumber();
+    }
+}
+