Rewrite non-dynamic pages using htaccess - apache

Question

I've been banging my head since many hours on this and I am unable to come up with a solution.
What I need to get done.
domain.com/page.php => domain.com/page/
domain.com/category1-name1.php => domain.com/category1/name1/
domain.com/category2-name1.php => domain.com/category2/name1/
Details: I have couple of files with the following names & I want them to be shown in the following way.
category1-name1.php => category1/name1/
category1-name2.php => category1/name2/
category1-name3.php => category1/name3/
category2-name100.php => category2/name100/
category2-something.php => category2/something/
category2-lipsum.php => category2/lipsum/
Also, I would like to achieve the following rewrite too
/category.php => /category/
/abcd.php => /abcd/
I'm trying but I can't achieve any of it.
I tried this code:
RewriteEngine On
RewriteRule ^category1/([^/]+)/?$ category1-$1.php [L]
RewriteRule ^category2/([^/]+)/?$ category2-$1.php [L]
RewriteRule ^([^/]*)/?$ $1.php [L]
Its only working for /abcd.php to /abcd/ and its throwing 404 errors on rest of the pages, even index is 404 due to it.

Answer 1

Try the following rules in your /htaccess file :
RewriteEngine On
RewriteCond %{THE_REQUEST} ^[A-Z]{3,}\s/([^.-]+)\.php [NC]
RewriteRule ^ %1/ [NC,R,L]
RewriteCond %{THE_REQUEST} ^[A-Z]{3,}\s/([^-]+)-([^.]+)\.php [NC]
RewriteRule ^ %1/%2/ [NC,R,L]
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule ^([^/]+)/?$ $1.php [QSA,NC,L]
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule ^([^/]+)/([^/]+)/?$ $1-$2.php [QSA,NC,L]