module Elasticsearch
  module API
    module Indices
      module Actions

        # Return information about segments for one or more indices.
        #
        # The response contains information about segment size, number of documents, deleted documents, etc.
        # See also {Indices::Actions#optimize}.
        #
        # @option arguments [List] :index A comma-separated list of index names; use `_all` or empty string
        #                                 to perform the operation on all indices
        # @option arguments [Boolean] :allow_no_indices Whether to ignore if a wildcard indices expression
        #                                               resolves into no concrete indices. (This includes `_all`
        #                                               string or when no indices have been specified)
        # @option arguments [String] :expand_wildcards Whether to expand wildcard expression to concrete indices
        #                                              that are open, closed or both. (options: open, closed)
        # @option arguments [String] :ignore_indices When performed on multiple indices, allows to ignore
        #                                            `missing` ones (options: none, missing) @until 1.0
        # @option arguments [Boolean] :ignore_unavailable Whether specified concrete indices should be ignored when
        #                                                 unavailable (missing, closed, etc)
        # @option arguments [Boolean] :verbose Whether to include detailed memory usage by Lucene (default: false)
        #
        # @see http://elasticsearch.org/guide/reference/api/admin-indices-segments/
        #
        def segments(arguments={})
          method = HTTP_GET
          path   = Utils.__pathify Utils.__listify(arguments[:index]), '_segments'

          params = Utils.__validate_and_extract_params arguments, ParamsRegistry.get(__method__)
          body   = nil

          perform_request(method, path, params, body).body
        end

        # Register this action with its valid params when the module is loaded.
        #
        # @since 6.2.0
        ParamsRegistry.register(:segments, [
            :ignore_indices,
            :ignore_unavailable,
            :allow_no_indices,
            :expand_wildcards,
            :verbose ].freeze)
      end
    end
  end
end