htaccess - detect mod_php

I'm trying to limit/eliminate duplication.

According to my (limited) understanding of some LAMP hosting providers (especially on shared servers) there are some PHP-ini directives that are ignored when set inside the PHP-script, but is accepted when set in the .htaccess; the process-flow should be quite simple:

• detect any mod_php* -and set an environment variable if found
• check this environment variable and set all php_value directives ONCE
• redirect all requests to PHP for handling requests according to config

The objective is to withhold all content unless PHP is available to handle the request according to config -- per user/bot/api/etc. ..and by this obviously not serve any PHP-code as text O_o

I have no idea why this has to be any more complicated, but I refuse to accept that I have to duplicate a (long) list of php_value directives 4 times -- just because the Apache-conf is too (expletive deleted) to handle the simplest logical conditions .. (face-desk) .. or maybe i just don't know enough about Apache-conf, please help; the code below throws a 400 error, and I can't get it to work unless I duplicate each block for every php-version -and each hosting provider's own mod_php*suffix -for PHP-version-hot-switching.

Here's what [bl/thr]ows:

<IfModule mod_rewrite.c>
    RewriteEngine On
    RewriteBase /

    <IfModule mod_php_null.c>
        SetEnv MODPHP 1
    </IfModule>
    <IfModule mod_php5.c>
        SetEnv MODPHP 1
    </IfModule>
    <IfModule mod_php7.c>
        SetEnv MODPHP 1
    </IfModule>

    <If "%{ENV:MODPHP} =1">
        php_value expose_php          Off
        php_value short_open_tag      On
        php_value display_errors      On
        php_value max_execution_time  60
        php_value default_charset     UTF-8
        # list shortened for brevity

        RewriteCond %{DOCUMENT_ROOT}/.auto.php -f
        RewriteRule ^(.*)$ .auto.php [L]
    </If>
</IfModule>

The code below works, however; note that:

• <IfModule mod_authz_core.c> is used to verify Apache2.4 -for <If>
• RewriteRule is used to define the variable
• REDIRECT_ is (conditionally) prefixed to the variable name
• RewriteCond %{ENV:MODPHP} ^1$ is used to test if the variable is 1.

<IfModule mod_rewrite.c>
    <IfModule mod_authz_core.c>
        RewriteEngine On
        RewriteBase /

        <IfModule mod_php_null.c>
            RewriteRule .* - [E=MODPHP:1]
        </IfModule>
        <IfModule mod_php5.c>
            RewriteRule .* - [E=MODPHP:1]
        </IfModule>
        <IfModule mod_php7.c>
            RewriteRule .* - [E=MODPHP:1]
        </IfModule>

        <If "%{ENV:REDIRECT_MODPHP} =1">
            php_value expose_php          Off
            php_value short_open_tag      On
            php_value display_errors      On
            php_value max_execution_time  60
            php_value default_charset     UTF-8
        </If>

        RewriteCond %{ENV:MODPHP} ^1$
        RewriteCond %{DOCUMENT_ROOT}/.auto.php -f
        RewriteRule ^(.*)$ .auto.php [L]
    </IfModule>
</IfModule>