# Routing extension
module Middleman
  module CoreExtensions
    class Routing < ConfigExtension
      # This should always run late, but not as late as :directory_indexes,
      # so it can add metadata to any pages generated by other extensions
      self.resource_list_manipulator_priority = 10

      # Expose the `page` method to config.
      expose_to_config :page

      PageDescriptor = Struct.new(:path, :metadata) do
        def execute_descriptor(app, resources)
          normalized_path = path.dup

          if normalized_path.is_a?(String) && !normalized_path.include?('*')
            # Normalize path
            normalized_path = ::Middleman::Util.normalize_path(normalized_path)
            if normalized_path.end_with?('/') || app.files.by_type(:source).watchers.any? { |w| (w.directory + Pathname(normalized_path)).directory? }
              normalized_path = ::File.join(normalized_path, app.config[:index_file])
            end
          end

          normalized_path = '/' + ::Middleman::Util.strip_leading_slash(normalized_path) if normalized_path.is_a?(String)

          resources
            .select { |r| ::Middleman::Util.path_match(normalized_path, "/#{r.path}") }
            .each { |r| r.add_metadata(metadata) }

          resources
        end
      end

      # The page method allows options to be set for a given source path, regex, or glob.
      # Options that may be set include layout, locals, andx ignore.
      #
      # @example
      #   page '/about.html', layout: false
      # @example
      #   page '/index.html', layout: :homepage_layout
      # @example
      #   page '/foo.html', locals: { foo: 'bar' }
      #
      # @param [String, Regexp] path A source path, or a Regexp/glob that can match multiple resources.
      # @params [Hash] opts Options to apply to all matching resources. Undocumented options are passed on as page metadata to be used by extensions.
      # @option opts [Symbol, Boolean, String] layout The layout name to use (e.g. `:article`) or `false` to disable layout.
      # @option opts [Boolean] directory_indexes Whether or not the `:directory_indexes` extension applies to these paths.
      # @option opts [Hash] locals Local variables for the template. These will be available when the template renders.
      # @option opts [Hash] data Extra metadata to add to the page. This is the same as frontmatter, though frontmatter will take precedence over metadata defined here. Available via {Resource#data}.
      # @return [void]
      Contract Or[String, Regexp], Hash => PageDescriptor
      def page(path, opts={})
        options = opts.dup

        # Default layout
        metadata = {
          locals: options.delete(:locals) || {},
          page: options.delete(:data) || {},
          options: options
        }

        PageDescriptor.new(path, metadata)
      end
    end
  end
end