Update queues by rearranging rows, rather than by blowing them away

[disorder] / disobedience / queue.c

diff --git a/disobedience/queue.c b/disobedience/queue.c
index 18d9d8b4366da0a6b363183910bfd27de90c2b59..817dc11bb725516f06113b361beea36eaff9c2f0 100644 (file)
--- a/disobedience/queue.c
+++ b/disobedience/queue.c
@@ -30,13 +30,41 @@ struct queue_entry *playing_track;
 /** @brief When we last got the playing track */
 time_t last_playing;
 
+static void queue_completed(void *v,
+                            const char *error,
+                            struct queue_entry *q);
+static void playing_completed(void *v,
+                              const char *error,
+                              struct queue_entry *q);
+
 /** @brief Called when either the actual queue or the playing track change */
 static void queue_playing_changed(void) {
-  struct queue_entry *q = xmalloc(sizeof *q);
 
-  *q = *actual_playing_track;
-  q->next = actual_queue;
-  playing_track = q;
+  /* Check that the playing track isn't in the queue.  There's a race here due
+   * to the fact that we issue the two commands at slightly different times.
+   * If it goes wrong we re-issue and try again, so that we never offer up an
+   * inconsistent state. */
+  if(actual_playing_track) {
+    struct queue_entry *q;
+    for(q = actual_queue; q; q = q->next)
+      if(!strcmp(q->id, actual_playing_track->id))
+        break;
+    if(q) {
+      disorder_eclient_playing(client, playing_completed, 0);
+      disorder_eclient_queue(client, queue_completed, 0);
+      return;
+    }
+  }
+  
+  struct queue_entry *q = xmalloc(sizeof *q);
+  if(actual_playing_track) {
+    *q = *actual_playing_track;
+    q->next = actual_queue;
+    playing_track = q;
+  } else {
+    playing_track = NULL;
+    q = actual_queue;
+  }
   time(&last_playing);          /* for column_length() */
   ql_new_queue(&ql_queue, q);
   /* Tell anyone who cares */
@@ -107,8 +135,11 @@ static gboolean playing_periodic(gpointer attribute((unused)) data) {
 static void queue_init(void) {
   /* Arrange a callback whenever the playing state changes */ 
   event_register("playing-changed", playing_changed, 0);
+  /* We reget both playing track and queue at pause/resume so that start times
+   * can be computed correctly */
   event_register("pause-changed", playing_changed, 0);
-  /* ...and when the queue changes */
+  event_register("pause-changed", queue_changed, 0);
+  /* Reget the queue whenever it changes */
   event_register("queue-changed", queue_changed, 0);
   /* ...and once a second anyway */
   g_timeout_add(1000/*ms*/, playing_periodic, 0);
@@ -116,12 +147,12 @@ static void queue_init(void) {
 
 /** @brief Columns for the queue */
 static const struct queue_column queue_columns[] = {
-  { "When",   column_when,     0,        1 },
+  { "When",   column_when,     0,        COL_RIGHT },
   { "Who",    column_who,      0,        0 },
-  { "Artist", column_namepart, "artist", 0 },
-  { "Album",  column_namepart, "album",  0 },
-  { "Title",  column_namepart, "title",  0 },
-  { "Length", column_length,   0,        1 }
+  { "Artist", column_namepart, "artist", COL_EXPAND|COL_ELLIPSIZE },
+  { "Album",  column_namepart, "album",  COL_EXPAND|COL_ELLIPSIZE },
+  { "Title",  column_namepart, "title",  COL_EXPAND|COL_ELLIPSIZE },
+  { "Length", column_length,   0,        COL_RIGHT }
 };
 
 /** @brief Pop-up menu for queue */
@@ -129,16 +160,17 @@ static struct queue_menuitem queue_menuitems[] = {
   { "Track properties", ql_properties_activate, ql_properties_sensitive, 0, 0 },
   { "Select all tracks", ql_selectall_activate, ql_selectall_sensitive, 0, 0 },
   { "Deselect all tracks", ql_selectnone_activate, ql_selectnone_sensitive, 0, 0 },
-  { "Scratch track", ql_scratch_activate, ql_scratch_sensitive, 0, 0 },
+  { "Scratch playing track", ql_scratch_activate, ql_scratch_sensitive, 0, 0 },
   { "Remove track from queue", ql_remove_activate, ql_remove_sensitive, 0, 0 },
 };
 
 struct queuelike ql_queue = {
+  .name = "queue",
   .init = queue_init,
   .columns = queue_columns,
   .ncolumns = sizeof queue_columns / sizeof *queue_columns,
   .menuitems = queue_menuitems,
-  .nmenuitems = sizeof queue_menuitems / sizeof *queue_menuitems,
+  .nmenuitems = sizeof queue_menuitems / sizeof *queue_menuitems
 };
 
 GtkWidget *queue_widget(void) {