[banshee] LastFM: AudioscrobblerService refactoring

[AndrÃs Aragoneses <aaragoneses src gnome org>]

commit 62f8bc84562b32e58fc36747c5c5c21331a62e87
Author: Phil Trimble <PhilTrimble gmail com>
Date:   Sun Feb 19 17:20:52 2012 +0000

    LastFM: AudioscrobblerService refactoring
    
    Move magic numbers to class fields; move core track validation into a
    separate method to avoid code duplication; and change dynamic casts to
    static casts where we don't check for null after the cast (so we would
    get InvalidCastException instead of NullReferenceException if the cast
    fails, even if unlikely).

 .../AudioscrobblerService.cs                       |   31 +++++++++++++------
 1 files changed, 21 insertions(+), 10 deletions(-)
---
diff --git a/src/Extensions/Banshee.Lastfm/Banshee.Lastfm.Audioscrobbler/AudioscrobblerService.cs b/src/Extensions/Banshee.Lastfm/Banshee.Lastfm.Audioscrobbler/AudioscrobblerService.cs
index 5e0758f..dc87acb 100644
--- a/src/Extensions/Banshee.Lastfm/Banshee.Lastfm.Audioscrobbler/AudioscrobblerService.cs
+++ b/src/Extensions/Banshee.Lastfm/Banshee.Lastfm.Audioscrobbler/AudioscrobblerService.cs
@@ -6,6 +6,7 @@
 //   Chris Toshok <toshok ximian com>
 //   Ruben Vermeersch <ruben savanne be>
 //   Aaron Bockover <aaron abock org>
+//   Phil Trimble <philtrimble gmail com>
 //
 // Copyright (C) 2005-2008 Novell, Inc.
 //
@@ -70,6 +71,9 @@ namespace Banshee.Lastfm.Audioscrobbler
         private DateTime song_start_time;
         private TrackInfo last_track;
 
+        private readonly TimeSpan MINIMUM_TRACK_DURATION = TimeSpan.FromSeconds (30);
+        private readonly TimeSpan MINIMUM_TRACK_PLAYTIME = TimeSpan.FromSeconds (240);
+
         public AudioscrobblerService ()
         {
         }
@@ -215,9 +219,17 @@ namespace Banshee.Lastfm.Audioscrobbler
 
         SongTimer st = new SongTimer ();
 
+        private bool IsValidForSubmission (TrackInfo track)
+        {
+            return (track.Duration > MINIMUM_TRACK_DURATION &&
+                    (track.MediaAttributes & TrackMediaAttributes.Music) != 0 &&
+                    !String.IsNullOrEmpty (track.ArtistName) &&
+                    !String.IsNullOrEmpty (track.TrackTitle));
+        }
+
         private void Queue (TrackInfo track) {
             if (track == null || st.PlayTime == 0 ||
-                !(actions["AudioscrobblerEnableAction"] as ToggleAction).Active) {
+                !((ToggleAction) actions["AudioscrobblerEnableAction"]).Active) {
 
                 return;
             }
@@ -225,10 +237,9 @@ namespace Banshee.Lastfm.Audioscrobbler
             Log.DebugFormat ("Track {3} had playtime of {0} msec ({4}sec), duration {1} msec, queued: {2}",
                 st.PlayTime, track.Duration.TotalMilliseconds, queued, track, st.PlayTime / 1000);
 
-            if (!queued && track.Duration.TotalSeconds > 30 &&
-                (track.MediaAttributes & TrackMediaAttributes.Music) != 0 &&
-                !String.IsNullOrEmpty (track.ArtistName) && !String.IsNullOrEmpty (track.TrackTitle) &&
-                (st.PlayTime > track.Duration.TotalMilliseconds / 2 || st.PlayTime > 240 * 1000)) {
+            if (!queued && IsValidForSubmission (track) &&
+                (st.PlayTime > track.Duration.TotalMilliseconds / 2 ||
+                 st.PlayTime > MINIMUM_TRACK_PLAYTIME.TotalMilliseconds)) {
                     if (!connection.Started) {
                         connection.Start ();
                     }
@@ -261,9 +272,9 @@ namespace Banshee.Lastfm.Audioscrobbler
                 case PlayerEvent.Iterate:
                     // Queue as now playing
                     if (!now_playing_sent && iterate_countdown == 0) {
-                        if (last_track != null && last_track.Duration.TotalSeconds > 30 &&
-                            (actions["AudioscrobblerEnableAction"] as ToggleAction).Active &&
-                            (last_track.MediaAttributes & TrackMediaAttributes.Music) != 0) {
+                        if (last_track != null &&
+                            IsValidForSubmission (last_track) &&
+                            ((ToggleAction) actions["AudioscrobblerEnableAction"]).Active) {
 
                             connection.NowPlaying (last_track.ArtistName, last_track.TrackTitle,
                                 last_track.AlbumTitle, last_track.Duration.TotalSeconds, last_track.TrackNumber);
@@ -292,14 +303,14 @@ namespace Banshee.Lastfm.Audioscrobbler
 
         private void OnToggleEnabled (object o, EventArgs args)
         {
-            Enabled = (o as ToggleAction).Active;
+            Enabled = ((ToggleAction) o).Active;
         }
 
         internal bool Enabled {
             get { return EngineEnabledSchema.Get (); }
             set {
                 EngineEnabledSchema.Set (value);
-                (actions["AudioscrobblerEnableAction"] as ToggleAction).Active = value;
+                ((ToggleAction) actions["AudioscrobblerEnableAction"]).Active = value;
             }
         }