.htaccess subdomain argument not accessible in query string

Question

I have written the following rules in .htaccess

RewriteCond %{HTTP_HOST} ^([^\.]+)\.domain\.com 
RewriteCond %1 !^www$ [NC]
RewriteCond %{REQUEST_URI} ^/news/news-details\.php$
RewriteRule (.*) news.php?div=%1

What it does is transfer the request the news.php file with the div variable equal to news/news-details.php. I do not need the div to be like that. I need the value of the subdomain that has been written with the domain like if the user is coming from user.domain.com/news/news-details.php. I need the div variable in the news.php file to be user i.e. news.php?div=user.

EDIT: Here is now the Htaccess code It is causing problem for the root news details page Options

+FollowSymLinks
RewriteEngine on

# For Accessing News Details Page for root http://www.domain.com/news/news-details.php
RewriteCond %{HTTP_HOST} ^www.domain\.com [NC]
RewriteRule ^news/news-details.php$ news.php [QSA,NC,L]


# For Accessing News Details Page http://user.domain.com/news/news-details.php
RewriteCond %{HTTP_HOST} ^(.+)\.domain\.com [NC]
RewriteCond %{HTTP_HOST) !^www\.
RewriteRule ^news/news-details.php$  news.php?div=%1 [QSA,NC,L


# For www.domain.com it should go to the index page
RewriteCond %{HTTP_HOST} ^(www\.)?domain.com$ [NC]
RewriteRule ^(.*)$ index.php [NC,L]


# For Accessing Divisions Page user.domain.com should go to domain.com/divisions.php?division=user
RewriteCond %{HTTP_HOST} !^www\.domain\.com$
RewriteCond %{HTTP_HOST} ^(.*)\.domain\.com$
RewriteRule ^$ /divisions.php?division=%1 [L]

AGAIN EDIT:

Here these two rules are conflicting

# For www.domain.com it should go to my-index.php page
#
RewriteCond %{HTTP_HOST} ^(www\.)?domain\.com$ [NC]
RewriteRule ^(.*)$ my-index.php [NC,L]


# For Page URL http://www.domain.com/news/news-details.php
#
RewriteCond %{REQUEST_URI} ^/news/news\-details\.php [NC]
RewriteCond %{HTTP_HOST} ^www\.domain\.com$  [NC]
RewriteRule ^(.*)$ my-news.php [NC,QSA,L]

Answer 1

Try this:

RewriteCond %{REQUEST_URI} ^/news/news\-details.php$
RewriteCond %{HTTP_HOST} ^([a-z0-9]+)\.domain\.com$  [NC]
RewriteCond %1 !^www$ [NC]
RewriteRule ^(.*)$ news.php?div=%1 [NC,QSA,L]

RewriteCond %{REQUEST_URI} ^/news/news\-details\.php [NC]
RewriteCond %{HTTP_HOST} ^www\.domain\.com$  [NC]
RewriteRule ^(.*)$ news.php [NC,QSA,L]

RewriteCond %{HTTP_HOST} ^www\.domain\.com$  [NC]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ index.php [NC,QSA,L]

RewriteCond %{HTTP_HOST} ^([a-z0-9]+)\.domain\.com$  [NC]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ divisions.php?division=%1 [NC,QSA,L]