[GSoC Update] Playdar Collection: Week 1

[Casey Link]

Hey Andy,

Nice first week update :)

>   A more interesting problem to consider with PlaydarMeta is that [..snip..]
> resulting in unplayable members in the playlist when Amarok is
> opened again. [..snip..]

I faced a similar issue back in my 2008 Summer of Code when I
implemented the MP3tunes Service.  The issue was that each track URL
had a unique session key that changed each time you logged in, which
obviously made it difficult to store a link to a track across
sessions.

Luckily, there was a unique track identifier that allowed me to
reconstruct the URL.

To solve it, your trackForUrl() and possiblyContainsTrack() are going
to have to be smart and robust enough to take those old URLs and
refactor them into new workable URLs. This process, of course, is
going to take time, so I recommend doing it in a Thread.

See Mp3tunesServiceCollection::trackForUrl for an example of how this works.

Best,
Casey