[Rhythmbox-devel] Context pane plugin improvements

[Mika Wahlroos <mpw iki fi>]

Hi all,

I've been thinking about some potential improvements to the already very 
interesting context pane to provide more interaction rather than just 
listing of contents. Perhaps there's already something like this in the 
original plans for the plugin. If nobody else is planning to do 
something similar, I'd like feedback from members of this list as to 
whether you think they're good ideas, how they could be developed 
further (I haven't thought about them very far yet), and whether they 
sound technically feasible.

Basically, I think it might be good if top tracks and albums displayed 
in the context pane for the currently playing artist weren't just lists 
of strings that can't be directly used for anything within Rhythmbox. 
Perhaps we could check if the user has the track (practically a track 
with the same artist, album and title) in their library, visually 
differentiate tracks available for playback from those that aren't 
available, and allow the user to e.g. jump to (or perhaps even directly 
play) an available track just by clicking it in the context pane, or to 
drag and drop the track into a playlist or the play queue.

Since users of the context pane are members of Last.fm (AFAIK it 
requires a valid account), maybe this could even be extended to check if 
the full track is available for streaming and offer to play it from 
there if it's not in the local library.

For albums we could perhaps check if there are tracks with the same 
artist and album title in the library and jump to the album in the 
browser. (I'm not quite sure if that's a good idea in case the user has 
the genre/artist/album browser hidden.)


A few concerns I've come up with so far:

Efficiency:
- Is searching for each displayed track in the database fast enough, 
even for large libraries? Granted, there aren't that many tracks shown 
so this might not be a significant issue.

Python bindings:
- Are all API functions that would be needed for these kinds of queries 
currently available to Python plugins (or, rather, is there any 
obviously required API that is *not* available)? Are there any potential 
threading issues?

UI and mental model:
- How should we clearly distinguish between tracks that are available 
for playback and those that aren't? I've thought about using a small 
icon, for example the same icon used for the library source to indicate 
that the track is available in the library.
- If clicking an available track started playing it, which source and 
context would it be playing from? Perhaps the library source (if the 
track is available there), but within which context? If the user has 
artist A selected in the library and now clicks on a track by artist B 
in the context pane, should the browser now have artist B selected? And 
so on.
- The previous question could be at least partially avoided if we e.g. 
just jumped to the track in the library browser when the user clicks on 
it in the context pane. However, if streaming from Last.fm is feasible, 
does the Last.fm source offer anything similar to this? The basic UI 
behaviour of track entries should of course be consistent whether the 
track is played locally or streamed online.

Last.fm API and terms:
- Do the Last.fm API and terms of use allow for such streaming if the 
full track is available for explicit playback on the Last.fm site?


I haven't written any code yet, and as mentioned above, I've also yet to 
check for the availability of necessary APIs. The implementation might 
actually be pretty simple but before I go on with it, I'd still welcome 
any feedback and insight on the potential issues mentioned above as well 
as anything else that comes to your mind, or whether you think it's 
feasible at all. And, of course, I'd like to know if someone is already 
working on something like this. :-)


Cheers,

Mika