webdav advice sought

[Thomas Lord]

I am working on a project that includes improving
"webdav support in Emacs".  I plan to submit patches
and/or new code.  I am writing to cross check my
thinking about how to do this before I get too
deeply into it.

I would appreciate helpful suggestions about
what information I'm missing, about which of my
alternative (tentative) plans makes the most sense,
and about what better plans I might have missed.

WebDAV is, of course, a protocol layered on top
of HTTP providing support for a remote file system.

I would like Emacs to be able to treat WebDAV servers
as a regular file system - to be able to "find-file"
a WebDAV file, to be able to save files, to have dired
work and so forth.  I would like advisory locking to work.
I would like to, at least by default, have auto-save files
go locally.   I am explicitly not, at this stage, concerned
with the WebDAV features and extensions related to versioning.

I understand that there is limited VC-mode support
for WebDAV though I don't know much about that yet.
That is not quite what I'm looking for (I think).  I
understand similarly about w3 mode webdav support.

I understand that there is some (somewhat bit-rotted) support
from a third party package called "eldav", which relies on 
an unmaintained program called "nd".   The current state
of ange-ftp-like support for WebDAV is a bit sad, as far
as I can tell.

First question: have I missed something about the current
state of things?

Second question:  what makes sense here?:

1. Try to rehabilitate eldav?
2. Try to adapt ange-ftp to use "cadaver", a command-line
   webdav client similar to typical ftp client programs?
3. Try to adapt tramp, again using cadaver?
4. Use ange and tramp as a guide but write a new set
   of file hooks, presumably using cadaver?
5. One of the above, but don't use cadaver, use ______?
6. Write C code for Emacs core (adding new library dependencies)?
7. Tom, you dummy, none of the above.  Instead ________?

I have my preferences from the above list but I
won't bias things yet by stating them.


Thanks and Regards,
-t