Unit CastleZip

Create a .zip file named ZipUrl containing all files (recursively) in the DirectoryUrl.

As usual in our engine, both parameters should be URLs. Although we also make reasonable effort to handle filenames when given.

Directory may but doesn't have to end with trailing /. The directory URL must, right now, resolve to a local directory (file URL), we cannot package other URL types.

SingleTopLevelDirectory meaning:

• When SingleTopLevelDirectory = True:

  The directory is added to the zip file as a top-level directory inside zip. E.g. if directory is 'file:///home/michalis/mydir', then the zip file will contain as top level 'mydir'. There shall be no trace of '/home/michalis/' in the resulting zp file.

• When SingleTopLevelDirectory = False:

  Then only contents of the directory are inside the zip, and so it can have multiple top-level entries.

We gracefully handle the case when ZIP file (ZipUrl) is inside the directory, by not packing the ZIP in this case in itself (and making a warning), to avoid possible reading and writing the file at the same time.