# Copyright 2015 Google Inc. All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.


require "gcloud/search/result/list"
require "gcloud/search/fields"

module Gcloud
  module Search
    ##
    # # Result
    #
    # See {Gcloud#search}
    class Result
      ##
      # @private Creates a new Result instance.
      def initialize
        @fields = Fields.new
        @raw = {}
      end

      ##
      # The unique identifier of the document referenced in the search result.
      #
      # @return [String]
      def doc_id
        @raw["docId"]
      end

      ##
      # The token for the next page of results.
      #
      # @return [String]
      def token
        @raw["nextPageToken"]
      end

      ##
      # Retrieve the field values associated to a field name.
      #
      # @param [String] name The name of the field. New values will be
      #   configured with this name.
      #
      # @return [FieldValue]
      #
      # @example
      #   require "gcloud"
      #
      #   gcloud = Gcloud.new
      #   search = gcloud.search
      #   index = search.index "products"
      #
      #   documents = index.search "best T-shirt ever"
      #   document = documents.first
      #   puts "The best match for your search is:"
      #   document["description"].each do |value|
      #     puts "* #{value} (#{value.type}) [#{value.lang}]"
      #   end
      #
      def [] name
        @fields[name]
      end

      # Trivial accessor because we want .fields to be listed with methods.

      ##
      # The fields in the search result. Each field has a name (String) and a
      # list of values ({FieldValues}). (See {Fields})
      def fields
        @fields
      end

      ##
      # Calls block once for each field, passing the field name and values pair
      # as parameters. If no block is given an enumerator is returned instead.
      # (See {Fields#each})
      #
      # @example
      #   require "gcloud"
      #
      #   gcloud = Gcloud.new
      #   search = gcloud.search
      #   index = search.index "products"
      #
      #   documents = index.search "best T-shirt ever"
      #   document = documents.first
      #   puts "The best match for your search is:"
      #   document.each do |name, values|
      #     puts "* #{name}:"
      #     values.each do |value|
      #       puts "  * #{value} (#{value.type})"
      #     end
      #   end
      #
      def each &block
        @fields.each(&block)
      end

      ##
      # Returns a new array populated with all the field names.
      # (See {Fields#names})
      #
      # @return [Array<String>]
      #
      # @example
      #   require "gcloud"
      #
      #   gcloud = Gcloud.new
      #   search = gcloud.search
      #   index = search.index "products"
      #
      #   documents = index.search "best T-shirt ever"
      #   document = documents.first
      #   puts "The best match has the following fields:"
      #   document.names.each do |name|
      #     puts "* #{name}:"
      #   end
      #
      def names
        @fields.names
      end

      ##
      # @private Override to keep working in interactive shells manageable.
      def inspect
        insp_token = ""
        if token
          trunc_token = "#{token[0, 8]}...#{token[-5..-1]}"
          trunc_token = token if token.length < 20
          insp_token = ", token: #{trunc_token.inspect}"
        end
        insp_fields = ", fields: (#{fields.names.map(&:inspect).join ', '})"
        "#{self.class}(doc_id: #{doc_id.inspect}#{insp_token}#{insp_fields})"
      end

      ##
      # @private New Result from a raw data object.
      def self.from_hash hash
        result = new
        result.instance_variable_set "@raw", hash
        result.instance_variable_set "@fields", Fields.from_raw(hash["fields"])
        result
      end

      ##
      # @private Returns the Result data as a hash
      def to_hash
        hash = @raw.dup
        hash["fields"] = @fields.to_raw
        hash
      end
    end
  end
end