module Jekyll
  module AutoScout24
    class BackupReader
      attr_reader :site, :content

      # ctor
      def initialize(site)
        @site = site
      end

      def read!(dir)
        # Load XML data from the backup file
        backup = Ox.load_file("#{dir}/autoscout24.xml")
        # Locate all vehicle nodes in the backup document
        vehicles, nodes = [], backup.locate("stx3/vehicle_data/vehicles/vehicle")
        # Transform each node found into an instance of Vehicle drop
        nodes.each { |n| vehicles << Vehicle.new(n) }
        # Merge current site data with the list of vehicles from the backup
        @site.data.merge!("autoscout24" => vehicles) unless vehicles.empty?
      end
    end

    # A drop in liquid is a class which allows you to export DOM like things to liquid.
    # Methods of drops are callable.
    # The main use for liquid drops is to implement lazy loaded objects.
    # If you would like to make data available to the web designers which you don't want loaded unless needed then
    # a drop is a great way to do that.
    class Vehicle < Liquid::Drop
      attr_reader :node

      # ctor
      def initialize(node)
        @node = node
      end

      # Catch all method to be flexible and adaptable based on the XML structure provided.
      def liquid_method_missing(name)
        found = @node.locate(name)
        return nil if found.empty?
        found.first.text
      end
    end
  end
end

# Plugin is activated after site data has been read and loaded from disk
Jekyll::Hooks.register :site, :post_read do |site|
  # We modify site.data collection in-place
  Jekyll::AutoScout24::BackupReader.new(site).read!(site.config["data_dir"])
end