Re: Any interest in using HTML for locally-installed Texinfo documentation?

[Gavin Smith]

On Sun, Nov 03, 2019 at 03:04:27PM +0100, Ludovic Courtès wrote:
> > The work is available on the webkitgit-info branch of the texinfo git
> > repository. I think it is developed to a point where it shows that a
> > browser for locally installed HTML documentation is clearly possible
> > with WebKitGTK. There are some notes in the README file on how to
> > build manuals for use with the browser.
> 
> [...]
> 
> > https://www.gnu.org/software/texinfo/video/demo.webm.
> 
> This looks very nice already!  It seems to me that the core features one
> would want are there: use of local copies of the manual, index search,
> browsing commands, etc.
> 
> Does the reader fall back to an on-line copy of manuals that are
> unavailable locally?  That would be nice, though it should probably
> first ask for user consent.

It doesn't do that yet.  It would have to look at an htmlxref.cnf file or 
equivalent, as the URL for the remote manual should not be in the locally 
installed documentation.

> I’d love to see an appropriate CSS applied by default to all the locally
> installed manual.  Perhaps the WebKitGTK code could “force” a CSS to
> each HTML page?

It is possible using webkit_web_view_new_with_user_content_manager.

> In the future, it’d be great to have syntax highlighting like we have at
> <https://guix.gnu.org/manual/devel/en/html_node/Using-the-Configuration-System.html>,
> but… I guess that’s another story.  :-)

How is that done? Are the HTML file post-processed somehow?

> What would be the next steps for you?  Do you plan to have this new
> reader released as part of the next Texinfo release, or as a separate
> package?

It would probably be for a separate package.  At the moment the program 
is called "infog" standing for "Info GTK".

There are various things that need to be done before it is ready for 
release:
* Allow installing the program, so that it can be run via PATH
* Handle external links in a web browser (using some kind of user 
desktop default)
* I'd like to make the index search completions in a separate pane 
rather than a pop-up menu, as in the "devhelp" program.
* Perhaps support for tabs
* The program uses a deprecated API in the WebKitGTK library to access 
the DOM of pages.  Allegedly it is possible to use JavaScript to do the 
same thing, but the documentation is not that helpful on how to do this.
* There is no text search facility in pages
* Standardize a location for installing HTML manuals.  What the GNU 
Coding Standards currently says about "htmldir" is insufficient, as a 
manual may have a different name to the package it is part of.
* It would be nice if the text input for a new window could be done as 
some kind of pop-over widget rather than in a separate dialog box.

I only have a few hours a week to spend on this, so it could take me 
some time to get through it.

I have been looking at tweaking the output of texi2any so the HTML looks 
better in this browser, including using mini-tables of contents instead 
of menus, and the table of contents linking to the top of a page rather 
than to an anchor a little down the page.