shared ssl 404 w/ existing htaccess - follow-up to /questions/12737308/ - .htaccess

Question

I hope asking a new question is the right approach to follow-up to an existing question(?) - please bear with me if not, I'm pretty much new to stackoverflow. That said, I'm referring to hide html extension + redirect .html version + special case exception
The htaccess provided by user Jon Lin works perfectly fine so far, but now I'm struggling with a related problem (I think it's related to the htaccess) and that is to use a shared ssl certificate for just one specific page on our site, let's call it baz.html
Due to the existing/cited htaccess, hxxp://mydomain.com/baz.html resolves to hxxp://mydomain.com/baz, which is fine. But, trying to use a shared ssl at hxxps://shared.host.com/~user/baz(.html) leads to a 404 not found error. I'm pretty sure (I assume so) that this is due to the used htaccess as the shared ssl tutorial provided by our host is pretty much unmistakeable.
Also, the document root (foo.html) shows up (as the only not-404) when accessing it with shared ssl but the CSS(+images), although relatively linked within the html code, isn't processed. I assume(?) this is related.
Basically, what I'd like to achieve is linking hxxps://shared.host.com/~user/baz instead of hxxp://mydomain.com/baz within our main site navigation to achieve a secured page (same as I do now for foo(.html), bar(.html), just for unsecured content)
I hope that my actual problem is perfectly understandable(?). I do not want to link our actual project page to not do self-advertising of some sort. If access to the actual page is needed to answer the question I'll certainly provide a link (if explicitly asked for)
Thanks in advance.

Answer 1

You can't use the same htaccess file in your shared SSL host because the base is different (/~user/ instead of just /), and that will change how all the rules inherently work. So for those same rules, you need to account for the different base. If you put these rules in the htaccess file in the /~user/ directory, they'd need to look like this:
EDIT: since they're the same document root, you need to duplicate all the rules, one for SSL, one not:
RewriteEngine On
# 1. hiding the .html extensions
RewriteCond %{HTTPS} on
RewriteCond %{REQUEST_URI} ^/(.*?)/?$
RewriteCond %{DOCUMENT_ROOT}/~user/%1.html -f
RewriteRule ^ /~user/%1.html [L]
RewriteCond %{HTTPS} off
RewriteCond %{REQUEST_URI} ^/(.*?)/?$
RewriteCond %{DOCUMENT_ROOT}/%1.html -f
RewriteRule ^ /%1.html [L]
# 2. 301 redirecting .html version
RewriteCond %{HTTPS} on
RewriteCond %{THE_REQUEST} ^[A-Z]{3,9}\ /~user/([^\ ]+)\.html
RewriteCond %1 !foo$
RewriteRule ^ /~user/%1 [L,R=301]
RewriteCond %{HTTPS} off
RewriteCond %{THE_REQUEST} ^[A-Z]{3,9}\ /([^\ ]+)\.html
RewriteCond %1 !foo$
RewriteRule ^ /%1 [L,R=301]
# 3. typing /foo.html to resolve to / as well as typing /foo to resolve to /
RewriteCond %{HTTPS} on
RewriteCond %{REQUEST_URI} ^/~user/(.*?/?)foo(\.html)?$
RewriteRule ^ /~user/%1 [L,R=301]
RewriteCond %{HTTPS} off
RewriteCond %{REQUEST_URI} ^/(.*?/?)foo(\.html)?$
RewriteRule ^ /%1 [L,R=301]
Now for the /baz and /baz.html to redirect to SSL, you'd need to add this before any of the rules (right under RewriteEngine On) in your domain.com document root (the non-SSL one):
EDIT: since the document root is the same, you need to add the condition to check whether it's SSL or not
RewriteCond %{HTTPS} off
RewriteRule ^/?baz(\.html)?/?$ http://shared.host.com/~user/baz [L,R=301]