htaccess to non www with SSL and file extension rewrite - .htaccess

Question

I have a website that rewrites the .php file extension so:
http://example.com/about.php
becomes
http://example.com/about
I also redirect www.domain.com to non www.
Now I am going to move it over to SSL, so I want to keep those 2 rules and redirect it all to https as well.
Here is what I currently have:
# Redirect to non www version
RewriteEngine On
RewriteCond %{HTTP_HOST} ^www.example.com
RewriteCond %{REQUEST_URI} !^/[0-9]+\..+\.cpaneldcv$
RewriteCond %{REQUEST_URI} !^/[A-F0-9]{32}\.txt(?:\ Comodo\ DCV)?$
RewriteCond %{REQUEST_URI} !^/\.well-known/pki-validation/[A-F0-9]{32}\.txt(?:\ Comodo\ DCV)?$
RewriteRule (.*) https://example.com/ [R=301,L]
RewriteCond %{REQUEST_URI} !^/[0-9]+\..+\.cpaneldcv$
RewriteCond %{REQUEST_URI} !^/[A-F0-9]{32}\.txt(?:\ Comodo\ DCV)?$
RewriteCond %{REQUEST_URI} !^/\.well-known/pki-validation/[A-F0-9]{32}\.txt(?:\ Comodo\ DCV)?$
RewriteRule ^index.php / [L,R=301]
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME}\.php -f
RewriteCond %{REQUEST_URI} !^/[0-9]+\..+\.cpaneldcv$
RewriteRule ^(.*)$ $1.php
ErrorDocument 404 /404.php
How can I do this without too many redirects? Thanks in advance!

Answer 1

Try it like this:
RewriteEngine On
RewriteCond %{HTTP_HOST} ^www\. [NC,OR]
RewriteCond %{HTTPS} off
RewriteCond %{HTTP_HOST} ^(?:www\.)?(.+)$ [NC]
RewriteCond %{REQUEST_URI} !^/[0-9]+\..+\.cpaneldcv$
RewriteCond %{REQUEST_URI} !^/[A-F0-9]{32}\.txt(?:\ Comodo\ DCV)?$
RewriteCond %{REQUEST_URI} !^/\.well-known/pki-validation/[A-F0-9]{32}\.txt(?:\ Comodo\ DCV)?$
RewriteRule ^ https://%1%{REQUEST_URI} [R=302,L,NE]
RewriteRule ^index.php / [L,R=301]
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME}\.php -f
RewriteCond %{REQUEST_URI} !^/[0-9]+\..+\.cpaneldcv$
RewriteRule ^(.*)$ $1.php
ErrorDocument 404 /404.php