libsaria: Sort list using comparison operator

It makes sense to define a function for sorting tracks as part of the
track class, rather than having to implement it externally.

include/libsaria/track.h

@@ -56,8 +56,7 @@ namespace libsaria
 			int get_channels();
 			sid_t get_songid();
 
-			string *get_artist_lc();
-			string *get_album_lc();
+			bool operator<(Track &);
 	};
 
 } /* Namespace: libsaria */

libsaria/library/list.cpp

@@ -14,33 +14,10 @@ using namespace std;
 static list<libsaria::Track *> play_list;
 static list<libsaria::Track *>::iterator cur_track = play_list.end();
 
-static inline bool compare_tracks(libsaria::Track *one, libsaria::Track *two)
+static bool compare_tracks(libsaria::Track *one, libsaria::Track *two)
 {
-	return one->get_track() < two->get_track();
-}
-
-static inline bool compare_albums(libsaria::Track *one, libsaria::Track *two)
-{
-	string *s_one = one->get_album_lc();
-	string *s_two = two->get_album_lc();
-	if (*s_one < *s_two)
-		return true;
-	else if (*s_one == *s_two)
-		return compare_tracks(one, two);
-	return false;
-}
-
-static bool compare_tracktags(libsaria::Track *one, libsaria::Track *two)
-{
-	string *s_one = one->get_artist_lc();
-	string *s_two = two->get_artist_lc();
-	if (*s_one == "")
-		return false;
-	if ( (*s_one < *s_two) || (*s_two == "") )
-		return true;
-	else if (*s_one == *s_two)
-		return compare_albums(one, two);
-	return false;
+	/* I want to compare tracks and not pointers... */
+	return *one < *two;
 }
 
 static bool find_id(sid_t &inode, list<libsaria::Track *>::iterator &it)
@@ -115,7 +92,7 @@ namespace libsaria
 		play_list.clear();
 		for (it = path_list->begin(); it != path_list->end(); it++)
 			insert_list(it->get_list());
-		play_list.sort(compare_tracktags);
+		play_list.sort(compare_tracks);
 	}
 
 	void library::for_each(SourceModel *model)

libsaria/track/get.cpp

@@ -69,14 +69,4 @@ namespace libsaria
 		return songid;
 	}
 
-	string *Track::get_artist_lc()
-	{
-		return artist_lc;
-	}
-
-	string *Track::get_album_lc()
-	{
-		return album_lc;
-	}
-
 } /* Namespace: libsaria */

libsaria/track/operator.cpp

@@ -0,0 +1,45 @@
+
+#include <libsaria/track.h>
+
+/*
+ * Return positive value if s1 > s2
+ * Return negative value if s1 < s2
+ * Return 0 s1 == s2
+ */
+static inline int compare_strings(string *s1, string *s2)
+{
+	/* List empty strings last */
+	if (*s1 == "")
+		return 1;
+	if (*s2 == "")
+		return -1;
+	return s1->compare(*s2);
+}
+
+namespace libsaria
+{
+
+	/* Return true if this < cmp_track */
+	bool Track::operator<(Track &cmp_track)
+	{
+		int cmp;
+
+		/* Compare artists */
+		cmp = compare_strings(artist_lc, cmp_track.artist_lc);
+		if (cmp < 0)
+			return true;
+		else if (cmp > 0)
+			return false;
+
+		/* Compare albums */
+		cmp = compare_strings(album_lc, cmp_track.album_lc);
+		if (cmp < 0)
+			return true;
+		else if (cmp > 0)
+			return false;
+
+		/* Compare tracks */
+		return track < cmp_track.track;
+	}
+
+}