Options +FollowSymlinks
RewriteEngine On
RewriteBase /_core/

# Ordner ausschließen
# RewriteCond     %{REQUEST_FILENAME}     -d
# RewriteRule     ^.*$  -  [L]

# (2) kein Slash am Ende
# RewriteCond %{REQUEST_URI} !/$
# (1) keine Dateiendung vorhanden ; Redirect auf REQUEST_URI mit /
# RewriteRule !\.[A-Za-z0-9]{2,4}$ %{REQUEST_URI}/ [R=301,L]

# rule for removing www on sub domains
# RewriteCond %{HTTP_HOST} ^www\.uba\.co2-rechner\.de$ [NC]
# RewriteRule (.*) https://uba.co2-rechner.de/$1 [R=301,L]

RewriteCond %{HTTPS} off
# First rewrite to HTTPS:
# Don't put www. here. If it is already there it will be included, if not
# the subsequent rule will catch it.
RewriteRule ^(.*)$ https://%{HTTP_HOST}%{REQUEST_URI} [L,R=301]

# Without subdomain: redirect to klimaktiv.de
RewriteCond %{HTTP_HOST} ^co2-rechner\.de$ [NC]
RewriteRule ^(.*)$ https://klimaktiv.co2-rechner.de/ [R=301,L]

# With www subdomain: redirect to klimaktiv.de
RewriteCond %{HTTP_HOST} ^www\.co2-rechner\.de$ [NC]
RewriteRule ^(.*)$ https://klimaktiv.co2-rechner.de/ [R=301,L]

# With subdomain: set customerID = subdomain
RewriteCond %{HTTP_HOST} ^(www\.)?(.+)\.co2-rechner\.de
RewriteRule ^([^/.]+)/([^/.]+)/([^/.]+)/?$ index.php?customerID=%2&langID=$1&cat=$2 [L,QSA]

# With subdomain: set customerID = subdomain
RewriteCond %{HTTP_HOST} ^(www\.)?(.+)\.co2-rechner\.de
RewriteRule ^([^/.]+)/([^/.]+)/?$ index.php?customerID=%2&langID=$1&cat=$2 [L,QSA]

# With subdomain: set customerID = subdomain
RewriteCond %{HTTP_HOST} ^(www\.)?(.+)\.co2-rechner\.de
RewriteRule ^([^/.]+)/?$ index.php?customerID=%2&langID=$1 [L,QSA]

# With subdomain: set customerID = subdomain
RewriteCond %{HTTP_HOST} ^(www\.)?(.+)\.co2-rechner\.de
RewriteRule ^$ index.php?customerID=%2 [L,QSA]