audio: New features and improvements

- Seek(), position() and duration() functions are implemented
  - There are bugs in the test program :(
- Clean up next()

Signed-off-by: Anna Schumaker <schumaker.anna@gmail.com>

design/audio.txt

@@ -38,11 +38,14 @@ Audio: (lib/audio.cpp)
 		Change the gstreamer state to either GST_STATE_PLAYING or
 		GST_STATE_PAUSED.  Return true on success and false otherwise.
 
-	bool audio :: seek_to(int)
-		Seek to a position X seconds into the track.  Return true if
-		a track is loaded and the seek isn't out of bounds.  False
+	bool audio :: seek_to(long)
+		Seek to a position X nanoseconds into the track.  Return true
+		if  track is loaded and the seek isn't out of bounds.  False
 		otherwise.
 
+		Seconds can be converted to nanoseconds by multiplying with
+		GST_SECOND.
+
 	void audio :: stop()
 		pause()
 		seek_to(0)
@@ -75,4 +78,5 @@ Audio: (lib/audio.cpp)
 
 	unsigned int audio :: pause_count()
 		Return the number of tracks that will be played before
-		playback pauses.
+		playback pauses.  Throw -1 if the user does not want us to
+		pause.

include/audio.h

@@ -15,9 +15,13 @@ namespace audio
 
 	bool play();
 	bool pause();
-	bool seek_to(double);
+	bool stop();
 	bool next();
+	unsigned int current_trackid();
 
+	bool seek_to(long);
+	long position();
+	long duration();
 };
 
 #endif /* OCARINA_AUDIO_H */

lib/audio.cpp

@@ -9,6 +9,7 @@
 
 static GstElement *ocarina_player;
 static bool track_loaded = false;
+static unsigned int cur_trackid = 0;
 
 static gboolean on_message(GstBus *bus, GstMessage *message, gpointer data)
 {
@@ -71,30 +72,73 @@ bool audio :: pause()
 	return change_state(GST_STATE_PAUSED);
 }
 
-bool audio :: seek_to(double pos)
+bool audio :: stop()
 {
+	if (pause() == false)
+		return false;
+	return seek_to(0);
+}
+
+bool audio :: seek_to(long pos)
+{
+	bool ret;
 	if (track_loaded == false)
 		return false;
-	return gst_element_seek_simple(GST_ELEMENT(ocarina_player),
+	ret = gst_element_seek_simple(GST_ELEMENT(ocarina_player),
 					GST_FORMAT_TIME,
 					GST_SEEK_FLAG_FLUSH,
 					pos);
+	return ret;
+}
+
+static bool _next()
+{
+	library :: Song song;
+	unsigned int id = deck :: next();
+
+	if (library :: lookup(id, &song) == false)
+		return false;
+	if (load_song(song) == false)
+		return false;
+	cur_trackid = id;
 	return true;
 }
 
 bool audio :: next()
 {
-	unsigned int id;
-	library :: Song song;
-
 	try {
-		id = deck :: next();
-		if (library :: lookup(id, &song) == false)
-			track_loaded = false;
-		else
-			track_loaded = load_song(song);
+		track_loaded = _next();
 	} catch (int) {
 		track_loaded = false;
 	}
 	return track_loaded;
 }
+
+unsigned int audio :: current_trackid()
+{
+	if (track_loaded == false)
+		throw -1;
+	return cur_trackid;
+}
+
+long audio :: position()
+{
+	long position;
+
+	if (track_loaded == false)
+		return 0;
+	if (!gst_element_query_position(GST_ELEMENT(ocarina_player), GST_FORMAT_TIME, &position))
+		return 0;
+	return position;
+}
+
+long audio :: duration()
+{
+	long duration;
+
+	if (track_loaded == false)
+		return 0;
+	if (!gst_element_query_duration(ocarina_player, GST_FORMAT_TIME, &duration))
+		return 0;
+	return duration;
+}

tests/audio/audio.cpp

@@ -25,6 +25,15 @@ void check_ret(const std :: string &test, bool ret, bool expected)
 		print("Failed.\n");
 }
 
+void check_ret(const std :: string &test, long ret, long expected)
+{
+	print("Test %s: ", test.c_str());
+	if (ret == expected)
+		print("Success!\n");
+	else
+		print("Failed (Expected %ld but got %ld)\n", expected, ret);
+}
+
 /* Call various functions without a track loaded */
 void test_0()
 {
@@ -32,15 +41,33 @@ void test_0()
 	check_ret("0b", audio :: pause(), false);
 	check_ret("0c", audio :: seek_to(10), false);
 	check_ret("0d", audio :: next(), false);
+	check_ret("0e", audio :: stop(), false);
+	check_ret("0f", audio :: position(), 0);
+	check_ret("0g", audio :: duration(), 0);
+	try {
+		print("Test 0h: ");
+		audio :: current_trackid();
+		print("Failed.\n");
+	} catch (int error) {
+		print("Success!\n");
+	}
 	print("\n");
 }
 
 void test_1()
 {
+	library :: Song song;
+	library :: lookup(0, &song);
+
 	check_ret("1a", audio :: next(), true);
 	check_ret("1b", audio :: play(), true);
 	check_ret("1c", audio :: pause(), true);
-	check_ret("1c", audio :: seek_to(10), true);
+	check_ret("1d", audio :: seek_to(1 * GST_SECOND), true);
+	check_ret("1e", audio :: position(), 1 * GST_SECOND);
+	check_ret("1f", audio :: stop(), true);
+	check_ret("1g", audio :: current_trackid() == 0, true);
+	check_ret("1h", audio :: position(), 0);
+	check_ret("1i", audio :: duration(), song.track->length);
 }
 
 int main(int argc, char **argv)