class Nameservice::AVAHI

# File lib/orocos/nameservice_avahi.rb, line 7
def initialize(options)
    super
    enable(options)
end

# File lib/orocos/nameservice_avahi.rb, line 12
def self.options
    @@options[:searchdomains] = "Search domains as hash of 'label' => 'domain, where a plain domainname will by default be expaned to _domain._tcp"

    @@options
end

# File lib/orocos/nameservice_avahi.rb, line 52
def enable(options)
    if enabled?
        warn "Nameservice: ignoring request to enable, because nameservice is already running"
        return
    end
       
    ## Introduce alternative avahi based nameserver if corba does not work
    begin 
        require 'servicediscovery'
        if not @avahi_nameserver
            @avahi_nameserver = ::Avahi::ServiceDiscovery.new
        end

        if not options.has_key?(:searchdomains)
            raise ArgumentError, "Nameservice: required option :searchdomains is not provided. Call enable with at least one searchdomain given"
        end

        # Start listening on the given domains (this does refer to the _myservice._tcp service domain and not(!) the .local domain)
        # we listen only 
        @avahi_nameserver.listen_on(options[:searchdomains])

    rescue LoadError
        raise LoadError, "Nameservice: 'distributed_nameserver' needs to be installed for AVAHI nameservice support"
    end
end

# File lib/orocos/nameservice_avahi.rb, line 19
def enabled?
    if @avahi_nameserver
        return true
    end
        
    return false
end

# File lib/orocos/nameservice_avahi.rb, line 32
def get_ior(name)
    ior = nil
    services = @avahi_nameserver.find_services(name)
    if services.empty?
        raise Orocos::NotFound, "AVAHI nameservice could not find a task named '#{name}'"
    elsif services.size > 1
        warn "Nameservice: multiple services '#{name}' found. Possibly due to publishing on IPv4 and IPv6, or on multiple interfaces -- picking first one in list"
    end

    service = services.first
    ior = service.get_description("IOR")
    if not ior 
        raise Orocos::NotFound, "AVAHI nameservice could not retrieve an ior for task #{name}"
    end
    
    return ior
end

# File lib/orocos/nameservice_avahi.rb, line 81
def resolve(name)
    ior = get_ior(name)
    result=nil
    if ior
        result = Orocos::CORBA.get(:do_get_from_ior, ior)
    else 
        raise Orocos::NotFound
    end
    result
end