require 'nokogiri'
require 'vagrant/util/network_ip'

module VagrantPlugins
  module ProviderLibvirt
    module Util
      module NetworkUtil
        include Vagrant::Util::NetworkIP

        def configured_networks(env, logger)
          management_network_name = env[:machine].provider_config.management_network_name
          management_network_address = env[:machine].provider_config.management_network_address
          logger.info "Using #{management_network_name} at #{management_network_address} as the management network"

          begin
            management_network_ip = IPAddr.new(management_network_address)
          rescue ArgumentError
            raise Errors::ManagementNetworkError,
              error_message: "#{management_network_address} is not a valid IP address"
          end

          # capture address into $1 and mask into $2
          management_network_ip.inspect =~ /IPv4:(.*)\/(.*)>/

          if $2 == '255.255.255.255'
            raise Errors::ManagementNetworkError,
              error_message: "#{management_network_address} does not include both an address and subnet mask"
          end

          management_network_options = {
            iface_type: :private_network,
            network_name: management_network_name,
            ip: $1,
            netmask: $2,
            dhcp_enabled: true,
            forward_mode: 'nat',
          }

          # add management network to list of networks to check
          networks = [ management_network_options ]

          env[:machine].config.vm.networks.each do |type, original_options|
            logger.debug "In config found network type #{type} options #{original_options}"
            # Options can be specified in Vagrantfile in short format (:ip => ...),
            # or provider format # (:libvirt__network_name => ...).
            # https://github.com/mitchellh/vagrant/blob/master/lib/vagrant/util/scoped_hash_override.rb
            options = scoped_hash_override(original_options, :libvirt)
            # store type in options
            # use default values if not already set
            options = {
              iface_type:  type,
              netmask:      '255.255.255.0',
              dhcp_enabled: true,
              forward_mode: 'nat',
            }.merge(options)
            # add to list of networks to check
            networks.push(options)
          end

          return networks
        end

        # Return a list of all (active and inactive) libvirt networks as a list
        # of hashes with their name, network address and status (active or not)
        def libvirt_networks(libvirt_client)
          libvirt_networks = []

          active = libvirt_client.list_networks
          inactive = libvirt_client.list_defined_networks

          # Iterate over all (active and inactive) networks.
          active.concat(inactive).each do |network_name|
            libvirt_network = libvirt_client.lookup_network_by_name(
              network_name)

            # Parse ip address and netmask from the network xml description.
            xml = Nokogiri::XML(libvirt_network.xml_desc)
            ip = xml.xpath('/network/ip/@address').first
            ip = ip.value if ip
            netmask = xml.xpath('/network/ip/@netmask').first
            netmask = netmask.value if netmask

            if xml.at_xpath('//network/ip/dhcp')
              dhcp_enabled = true
            else
              dhcp_enabled = false
            end

            # Calculate network address of network from ip address and
            # netmask.
            if ip && netmask
              network_address = network_address(ip, netmask)
            else
              network_address = nil
            end

            libvirt_networks << {
              name:             network_name,
              ip_address:       ip,
              netmask:          netmask,
              network_address:  network_address,
              dhcp_enabled:     dhcp_enabled,
              bridge_name:      libvirt_network.bridge_name,
              created:          true,
              active:           libvirt_network.active?,
              autostart:        libvirt_network.autostart?,
              libvirt_network:  libvirt_network
            }
          end

          libvirt_networks
        end

      end
    end
  end
end