Redirect iRule and replace only part of the URI

Eventually this is what I implemented.

Thanks for your help.

when HTTP_REQUEST {

    if { [string tolower [HTTP::host]] equals "oldsite.domain.com" }
        {
            set NEWURI [string map "oldsite newsite" [HTTP::uri]]
            set NEWURI [string map "oldstring newstring" $NEWURI]
            set NEWURL https://newsite.domain.com$NEWURI
            HTTP::respond 200 content "
            
            
            
            Your page has moved !
            
            
            
            
            Your page has moved !
            The website you have requested has been migrated to 
            
            You will be automatically redirected to the new address in 5 seconds.
            Please bookmark the next page.
            
            
            Thank you for your cooperation.
            
            

            
            
            

            " noserver
            return

        }

}