Limit random choice of score to search paramters in URL

[craigsapp]

The id random will display the work page of a random score:

https://polishscores.org/?id=random

Such as:

https://polishscores.org/?id=pl-kk--kk-i-336--002

When search parameters are also given, then apply the search first, and then choose a random work from the search results.

For example

https://polishscores.org/?id=random&c=Gimeshoffer

Should return a random work from the list of three works by the composer Gimeshoffer:

[craigsapp]

Implemented in commit https://github.com/craigsapp/website-polish-scores/commit/465037e2825a20f4cad4ca93ced7b9d98dda61b8

https://polishscores.org/?id=random&c=Kaspar

Goes to: https://polishscores.org/?id=pl-kk--kk-i-397--001-003

Running again:

https://polishscores.org/?id=random&c=Kaspar

Goes to https://polishscores.org/?id=pl-kk--kk-i-397--001-002

Going to the browse page, the Composer field is filled in:

[craigsapp]

Sometimes the lyrics and pitch search indexes are not loaded from the server when loading a random work:

Probably related to a limit in the number of active downloads from a single server in the web browser (they could be competing with the files downloaded when display the random work page). Try delaying download of these indexes (all the time, or when a random work is being loaded).

[craigsapp]

Random work from a library:

https://polishscores.org/?s=PL-Kc&id=random

goes in this case to https://polishscores.org/?id=pl-kc--40102-iii-1-saf--002-023

Successive clicking on the random button in the navigator:

will subsequently take you to other random works in the archive/library (since the PL-Kc library is selected on the browse page and a search has been done before choosing a random work in that library from the URL).