module Fog
  module Vcloud
    class Compute
      module Shared
        private

        def validate_vapp_data(vapp_data)
          valid_opts = [:name, :cpus, :memory, :disks]
          unless valid_opts.all? { |opt| vapp_data.has_key?(opt) }
            raise ArgumentError.new("Required Vapp data missing: #{(valid_opts - vapp_data.keys).map(&:inspect).join(", ")}")
          end
        end
      end

      class Real
        include Shared

        def generate_configure_vapp_request(vapp_uri, vapp_data)
          rasd_xmlns = { "xmlns" => "http://schemas.dmtf.org/wbem/wscim/1/cim-schema/2/CIM_ResourceAllocationSettingData" }

          xml = Nokogiri::XML(request( :uri => vapp_uri).body)
          xml.root['name'] = vapp_data[:name]

          #cpu
          xml.at("//xmlns:ResourceType[.='3']/..", rasd_xmlns).at('.//xmlns:VirtualQuantity', rasd_xmlns).content = vapp_data[:cpus]

          #memory
          xml.at("//xmlns:ResourceType[.='4']/..", rasd_xmlns).at('.//xmlns:VirtualQuantity', rasd_xmlns).content = vapp_data[:memory]

          #disks
          real_disks = xml.xpath("//xmlns:ResourceType[ .='17']/..", rasd_xmlns)
          real_disk_numbers = real_disks.map { |disk| disk.at('.//xmlns:AddressOnParent', rasd_xmlns).content }
          disk_numbers = vapp_data[:disks].map { |vdisk| vdisk[:number].to_s }

          if vapp_data[:disks].length < real_disks.length
            #Assume we're removing a disk
            remove_disk_numbers = real_disk_numbers - disk_numbers
            remove_disk_numbers.each do |number|
              if result = xml.at("//xmlns:ResourceType[ .='17']/../xmlns:AddressOnParent[.='#{number}']/..", rasd_xmlns)
                result.remove
              end
            end
          elsif vapp_data[:disks].length > real_disks.length
            add_disk_numbers = disk_numbers - real_disk_numbers

            add_disk_numbers.each do |number|
              new_disk = real_disks.first.dup
              new_disk.at('.//xmlns:AddressOnParent', rasd_xmlns).content = -1
              new_disk.at('.//xmlns:VirtualQuantity', rasd_xmlns).content = vapp_data[:disks].detect { |disk| disk[:number].to_s == number.to_s }[:size]
              real_disks.first.parent << new_disk
            end
          end

          #puts xml.root.to_s
          xml.root.to_s

          #builder = Builder::XmlMarkup.new
          #builder.Vapp(:href => vapp_uri.to_s,
          #             :type => 'application/vnd.vmware.vcloud.vApp+xml',
          #             :name => vapp_data[:name],
          #             :status => 2,
          #             :size => 0,
          #             :xmlns => 'http://www.vmware.com/vcloud/v0.8',
          #             :"xmlns:xsi" => 'http://www.w3.org/2001/XMLSchema-instance',
          #             :"xmlns:xsd" => 'http://www.w3.org/2001/XMLSchema') {
          #  #builder.VirtualHardwareSection(:xmlns => 'http://schemas.dmtf.org/ovf/envelope/1') {
          #  builder.Section(:"xsi:type" => "q2:VirtualHardwareSection_Type", :xmlns => "http://schemas.dmtf.org/ovf/envelope/1", :"xmlns:q2" => "http://www.vmware.com/vcloud/v0.8") {
          #    builder.Info('Virtual Hardware')
          #    builder.Item(:xmlns => 'http://schemas.dmtf.org/ovf/envelope/1') {
          #    #builder.Item {
          #      builder.InstanceID(1, :xmlns => 'http://schemas.dmtf.org/wbem/wscim/1/cim-schema/2/CIM_ResourceAllocationSettingData')
          #      builder.ResourceType(3, :xmlns => 'http://schemas.dmtf.org/wbem/wscim/1/cim-schema/2/CIM_ResourceAllocationSettingData')
          #      builder.VirtualQuantity(vapp_data[:cpus], :xmlns => 'http://schemas.dmtf.org/wbem/wscim/1/cim-schema/2/CIM_ResourceAllocationSettingData')
          #    }
          #    builder.Item(:xmlns => 'http://schemas.dmtf.org/ovf/envelope/1') {
          #    #builder.Item {
          #      builder.InstanceID(2, :xmlns => 'http://schemas.dmtf.org/wbem/wscim/1/cim-schema/2/CIM_ResourceAllocationSettingData')
          #      builder.ResourceType(4, :xmlns => 'http://schemas.dmtf.org/wbem/wscim/1/cim-schema/2/CIM_ResourceAllocationSettingData')
          #      builder.VirtualQuantity(vapp_data[:memory], :xmlns => 'http://schemas.dmtf.org/wbem/wscim/1/cim-schema/2/CIM_ResourceAllocationSettingData')
          #    }
          #    vapp_data[:disks].each do |disk_data|
          #      #builder.Item(:xmlns => 'http://schemas.dmtf.org/ovf/envelope/1') {
          #      builder.Item {
          #        builder.AddressOnParent(disk_data[:number], :xmlns => 'http://schemas.dmtf.org/wbem/wscim/1/cim-schema/2/CIM_ResourceAllocationSettingData')
          #        builder.HostResource(disk_data[:resource], :xmlns => 'http://schemas.dmtf.org/wbem/wscim/1/cim-schema/2/CIM_ResourceAllocationSettingData')
          #        builder.InstanceID(9, :xmlns => 'http://schemas.dmtf.org/wbem/wscim/1/cim-schema/2/CIM_ResourceAllocationSettingData')
          #        builder.ResourceType(17, :xmlns => 'http://schemas.dmtf.org/wbem/wscim/1/cim-schema/2/CIM_ResourceAllocationSettingData')
          #        builder.VirtualQuantity(disk_data[:size], :xmlns => 'http://schemas.dmtf.org/wbem/wscim/1/cim-schema/2/CIM_ResourceAllocationSettingData')
          #      }
          #    end
          #
          #  }
          #}
        end

        def configure_vapp(vapp_uri, vapp_data)
          validate_vapp_data(vapp_data)

          request(
            :body     => generate_configure_vapp_request(vapp_uri, vapp_data),
            :expects  => 202,
            :headers  => {'Content-Type' => 'application/vnd.vmware.vcloud.vApp+xml' },
            :method   => 'PUT',
            :uri      => vapp_uri,
            :parse    => true
          )
        end

      end
    end
  end
end
