Convert Microsoft rewrite rules to iRule

Here is my attempt. I'm sure it needs help. Would appreciate if someone could take a look...

when HTTP_REQUEST {
    If client IP matches allow the request and replace the host header.
    if { [IP::addr [IP::client_addr] equals 280.34.72.0/26] } {
        HTTP::header replace Host "server003.ab.abc.com"
    }
    Add a trailing slash to the url except if it contains a folder or filename.
    set uri_base [URI::basename [HTTP::path]]
    if {$uri_base equals ""} {
       The URI::basename is /folder/
    } elseif {$uri_base contains "."} {
       The URI::basename is *.* file
    } else {
        HTTP::path "[HTTP::path]/"
        HTTP::respond 301 "Location" "[HTTP::path]"
        return
  }
}
when HTTP_RESPONSE { 
    Strip host header.
    if { [HTTP::host][HTTP::uri] equals "server003.ab.abc.com/KeyManager/[HTTP::uri]" {
        HTTP::uri "/[HTTP::uri]"
    Set relative paths.
    } elseif { [HTTP::uri contains "/[HTTP::uri]" }
        HTTP::uri "/[HTTP::uri]"
    }

}