# frozen_string_literal: true

module Anthropic
  module Internal
    # @generic Elem
    #
    # @example
    #   if page.has_next?
    #     page = page.next_page
    #   end
    #
    # @example
    #   page.auto_paging_each do |batch|
    #     puts(batch)
    #   end
    class Page
      include Anthropic::Internal::Type::BasePage

      # @return [Array<generic<Elem>>, nil]
      attr_accessor :data

      # @return [Boolean]
      attr_accessor :has_more

      # @return [String, nil]
      attr_accessor :first_id

      # @return [String, nil]
      attr_accessor :last_id

      # @api private
      #
      # @param client [Anthropic::Internal::Transport::BaseClient]
      # @param req [Hash{Symbol=>Object}]
      # @param headers [Hash{String=>String}, Net::HTTPHeader]
      # @param page_data [Hash{Symbol=>Object}]
      def initialize(client:, req:, headers:, page_data:)
        super
        model = req.fetch(:model)

        case page_data
        in {data: Array | nil => data}
          @data = data&.map { Anthropic::Internal::Type::Converter.coerce(model, _1) }
        else
        end

        case page_data
        in {has_more: true | false | nil => has_more}
          @has_more = has_more
        else
        end

        case page_data
        in {first_id: String | nil => first_id}
          @first_id = first_id
        else
        end

        case page_data
        in {last_id: String | nil => last_id}
          @last_id = last_id
        else
        end
      end

      # @return [Boolean]
      def next_page?
        has_more
      end

      # @raise [Anthropic::HTTP::Error]
      # @return [Anthropic::Internal::Page]
      def next_page
        unless next_page?
          message = "No more pages available. Please check #next_page? before calling ##{__method__}"
          raise RuntimeError.new(message)
        end

        req = Anthropic::Internal::Util.deep_merge(
          @req,
          {query: first_id.nil? ? {after_id: last_id} : {before_id: first_id}}
        )
        @client.request(req)
      end

      # @param blk [Proc]
      #
      # @yieldparam [generic<Elem>]
      def auto_paging_each(&blk)
        unless block_given?
          raise ArgumentError.new("A block must be given to ##{__method__}")
        end
        page = self
        loop do
          page.data&.each { blk.call(_1) }
          break unless page.next_page?
          page = page.next_page
        end
      end

      # @return [String]
      def inspect
        # rubocop:disable Layout/LineLength
        "#<#{self.class}:0x#{object_id.to_s(16)} data=#{data.inspect} has_more=#{has_more.inspect} first_id=#{first_id.inspect} last_id=#{last_id.inspect}>"
        # rubocop:enable Layout/LineLength
      end
    end
  end
end