Ticket #4076: artistshuffle.patch.mythmusic

Index: configure
===================================================================
--- configure   (revision 14675)
+++ configure   (working copy)
@@ -21,7 +21,7 @@
 controls="yes"
 flix="yes"
 archive="yes"
-zoneminder="yes"
+zoneminder="no"
 movies="yes"
 
 cc="gcc"
Index: mythmusic/mythmusic/playbackbox.cpp
===================================================================
--- mythmusic/mythmusic/playbackbox.cpp (revision 14675)
+++ mythmusic/mythmusic/playbackbox.cpp (working copy)
@@ -121,6 +121,8 @@
         setShuffleMode(SHUFFLE_INTELLIGENT);
     else if (playmode.lower() == "album")
         setShuffleMode(SHUFFLE_ALBUM);
+    else if (playmode.lower() == "artist")
+        setShuffleMode(SHUFFLE_ARTIST);
     else
         setShuffleMode(SHUFFLE_OFF);
 
@@ -269,6 +271,8 @@
         gContext->SaveSetting("PlayMode", "random");
     else if (shufflemode == SHUFFLE_ALBUM)
         gContext->SaveSetting("PlayMode", "album");
+    else if (shufflemode == SHUFFLE_ARTIST)
+        gContext->SaveSetting("PlayMode", "artist");
     else
         gContext->SaveSetting("PlayMode", "none");
 
@@ -1639,6 +1643,21 @@
 
             bannerEnable(tr("Shuffle: Album"), 4000);
             break;
+        case SHUFFLE_ARTIST:
+            if(shuffle_button)
+            {
+                if (keyboard_accelerators)
+                    shuffle_button->setText(tr("1 Shuffle: Artist"));
+                else
+                    shuffle_button->setText(tr("Shuffle: Artist"));
+            }
+            music_tree_list->scrambleParents(true);
+
+            if (class LCD *lcd = LCD::Get())
+                lcd->setMusicShuffle(LCD::MUSIC_SHUFFLE_ARTIST);
+
+            bannerEnable(tr("Shuffle: Artist"), 4000);
+            break;        
         default:
             if(shuffle_button)
             {
@@ -1817,6 +1836,7 @@
     playlist_tree->setAttribute(1, 0);
     playlist_tree->setAttribute(2, 0);
     playlist_tree->setAttribute(3, 0);
+    playlist_tree->setAttribute(4, 0);
 
     // We ask the playlist object to write out the whole tree (all playlists 
     // and all music). It will set attributes for nodes in the tree, such as 
Index: mythmusic/mythmusic/playlist.cpp
===================================================================
--- mythmusic/mythmusic/playlist.cpp    (revision 14675)
+++ mythmusic/mythmusic/playlist.cpp    (working copy)
@@ -931,8 +931,12 @@
     AlbumMap                       album_map;
     AlbumMap::iterator             Ialbum;
     QString                        album;
-
-
+    
+    typedef map<QString, uint32_t> ArtistMap;
+    ArtistMap                      artist_map;
+    ArtistMap::iterator            Iartist;
+    QString                        artist;
+    
     for(it = songs.first(); it; it = songs.next())
     {
         if(!it->getCDFlag())
@@ -959,10 +963,26 @@
                         else if (tmpdata->LastPlay() > lastplayMax) { lastplayMax = tmpdata->LastPlay(); }
                     }
                 }
+                
+                // pre-fill the artist map with the artist name and song title
+                artist = tmpdata->Artist() + "~" + tmpdata->Title();
+                if ((Iartist = artist_map.find(artist)) == artist_map.end()) 
+                {
+                  artist_map.insert(ArtistMap::value_type(artist,
+                                                        0));
+                }
             }
         }
     }
 
+    // populate the sort id into the artist map
+    uint32_t count = 1; 
+    for( Iartist = artist_map.begin(); Iartist != artist_map.end(); Iartist++ ) 
+    {
+        Iartist->second = count;
+        count++;
+    }    
+    
     int RatingWeight = 2;
     int PlayCountWeight = 2;
     int LastPlayWeight = 2;
@@ -1030,6 +1050,23 @@
                       integer_rating += tmpdata->Track();
                       added_node->setAttribute(4, integer_rating);
                     }
+                    
+                    // "artist" order, sorts by artist name then track title
+                    // uses the pre-prepared artist map to do this
+                    uint32_t integer_order;
+                    artist = tmpdata->Artist() + "~" + tmpdata->Title();
+                    if ((Iartist = artist_map.find(artist)) == artist_map.end())
+                    {
+                        // we didn't find this track in the map, yet we pre-loaded them all
+                        // we are broken, but we just set the track order to 1, since there
+                        // is no real point in reporting an error
+                        integer_order = 1;
+                    }
+                    else
+                    {
+                        integer_order = Iartist->second;
+                    }    
+                    added_node->setAttribute(5, integer_order);
                 }
             }
             if(it->getValue() < 0)
Index: mythmusic/mythmusic/playbackbox.h
===================================================================
--- mythmusic/mythmusic/playbackbox.h   (revision 14675)
+++ mythmusic/mythmusic/playbackbox.h   (working copy)
@@ -140,6 +140,7 @@
       SHUFFLE_RANDOM, 
       SHUFFLE_INTELLIGENT,
       SHUFFLE_ALBUM,
+      SHUFFLE_ARTIST,
       MAX_SHUFFLE_MODES 
     };
     enum ResumeMode