module Awsum
  class Ec2
    class Volume
      attr_reader :id, :instance_id, :size, :status, :create_time, :snapshot_id, :device, :attach_time, :availability_zone, :attachment_status

      def initialize(ec2, id, instance_id, size, status, create_time, snapshot_id, device, attach_time, availability_zone, attachment_status) #:nodoc:
        @ec2 = ec2
        @id = id
        @instance_id = instance_id
        @size = size
        @status = status
        @create_time = create_time
        @snapshot_id = snapshot_id
        @device = device
        @attach_time = attach_time
        @availability_zone = availability_zone
        @attachment_status = attachment_status
      end

      # Will reload the information about this Volume
      #
      # Useful for when a volume has just been created but is not yet available
      #   while volume.status != 'available'
      #     volume.reload
      #   end
      def reload
        reloaded_volume = @ec2.volume id

        @id = id
        @instance_id = reloaded_volume.instance_id
        @size = reloaded_volume.size
        @status = reloaded_volume.status
        @create_time = reloaded_volume.create_time
        @snapshot_id = reloaded_volume.snapshot_id
        @device = reloaded_volume.device
        @attach_time = reloaded_volume.attach_time
        @availability_zone = reloaded_volume.availability_zone
        @attachment_status = reloaded_volume.attachment_status
      end

      # Detach this volume
      def detach(force = false)
        @ec2.detach_volume id, :force => force
      end

      # Delete this volume
      def delete
        @ec2.delete_volume id
      end

      # Creates a Snapshot of this Volume
      def create_snapshot
        @ec2.create_snapshot id
      end

      # Lists the Snapshot(s) of this Volume
      def snapshots
        snapshots = @ec2.snapshots
        snapshots.delete_if {|s| s.volume_id != id}
      end
    end

    class VolumeParser < Awsum::Parser #:nodoc:
      def initialize(ec2)
        @ec2 = ec2
        @volumes = []
        @text = nil
        @stack = []
      end

      def tag_start(tag, attributes)
        #Quick hack so we can use the same parser for CreateVolume which doesn't use the item tag to wrap the volume information
        if tag == 'CreateVolumeResponse'
          @stack << 'volumeSet'
        end

        case tag
          when 'volumeSet'
            @stack << 'volumeSet'
          when 'attachmentSet'
            @stack << 'attachmentSet'
          when 'item', 'CreateVolumeResponse'
            case @stack[-1]
              when 'volumeSet'
                @current = {}
              when 'attachmentSet'
            end
        end
        @text = ''
      end

      def text(text)
        @text << text unless @text.nil?
      end

      def tag_end(tag)
        case tag
          when 'DescribeVolumesResponse'
            #no-op
          when 'volumeSet', 'attachmentSet'
            @stack.pop
          when 'item', 'CreateVolumeResponse'
            case @stack[-1]
              when 'volumeSet'
                @volumes << Volume.new(
                                @ec2,
                                @current['volumeId'], 
                                @current['instanceId'], 
                                @current['size'].to_i, 
                                @current['status'],
                                @current['createTime'].blank? ? nil :Time.parse(@current['createTime']),
                                @current['snapshotId'], 
                                @current['device'],
                                @current['attachTime'].blank? ? nil :Time.parse(@current['attachTime']),
                                @current['availabilityZone'],
                                @current['attachment_status']
                              )
            end
          else
            unless @text.nil? || @current.nil?
              text = @text.strip
              #Handle special case for attachmentSet/status
              if @stack[-1] == 'attachmentSet' && tag == 'status'
                @current['attachment_status'] = (text == '' ? nil : text)
              else
                @current[tag] = (text == '' ? nil : text)
              end
            end
        end
      end

      def result
        @volumes
      end
    end
  end
end