require 'spec_helper'

describe FastJsonapi::ObjectSerializer do
  include_context 'movie class'
  include_context 'ams movie class'

  context 'when testing performance of serialization' do
    it 'should create a hash of 1000 records in less than 25 ms' do
      movies = 1000.times.map { |_i| movie }
      expect { MovieSerializer.new(movies).serializable_hash }.to perform_under(25).ms
    end

    it 'should serialize 1000 records to jsonapi in less than 30 ms' do
      movies = 1000.times.map { |_i| movie }
      expect { MovieSerializer.new(movies).serialized_json }.to perform_under(30).ms
    end

    it 'should create a hash of 1000 records with includes and meta in less than 75 ms' do
      count = 1000
      movies = count.times.map { |_i| movie }
      options = {}
      options[:meta] = { total: count }
      options[:include] = [:actors]
      expect { MovieSerializer.new(movies, options).serializable_hash }.to perform_under(75).ms
    end

    it 'should serialize 1000 records to jsonapi with includes and meta in less than 75 ms' do
      count = 1000
      movies = count.times.map { |_i| movie }
      options = {}
      options[:meta] = { total: count }
      options[:include] = [:actors]
      expect { MovieSerializer.new(movies, options).serialized_json }.to perform_under(75).ms
    end
  end

  def print_stats(count, ams_time, our_time)
    format = '%-15s %-10s %s'
    puts ''
    puts format(format, 'Serializer', 'Records', 'Time')
    puts format(format, 'AMS serializer', count, ams_time.round(2).to_s + ' ms')
    puts format(format, 'Fast serializer', count, our_time.round(2).to_s + ' ms')
  end

  context 'when comparing with AMS 0.10.x' do
    [1, 25, 250, 1000].each do |movie_count|
      speed_factor = 25
      it "should serialize #{movie_count} records atleast #{speed_factor} times faster than AMS" do
        ams_movies = build_ams_movies(movie_count)
        movies = build_movies(movie_count)
        our_json = nil
        ams_json = nil
        our_serializer = MovieSerializer.new(movies)
        ams_serializer = ActiveModelSerializers::SerializableResource.new(ams_movies)
        our_time = Benchmark.measure { our_json = our_serializer.serialized_json }.real * 1000
        ams_time = Benchmark.measure { ams_json = ams_serializer.to_json }.real * 1000
        print_stats(movie_count, ams_time, our_time)
        expect(our_json.length).to eq ams_json.length
        expect { our_serializer.serialized_json }.to perform_faster_than { ams_serializer.to_json }.at_least(speed_factor).times
      end
    end
  end

  context 'when comparing with AMS 0.10.x and with includes and meta' do
    [1, 25, 250, 1000].each do |movie_count|
      speed_factor = 25
      it "should serialize #{movie_count} records atleast #{speed_factor} times faster than AMS" do
        ams_movies = build_ams_movies(movie_count)
        movies = build_movies(movie_count)
        our_json = nil
        ams_json = nil

        options = {}
        options[:meta] = { total: movie_count }
        options[:include] = [:actors, :movie_type]

        our_serializer = MovieSerializer.new(movies, options)
        ams_serializer = ActiveModelSerializers::SerializableResource.new(ams_movies, include: options[:include], meta: options[:meta])
        our_time = Benchmark.measure { our_json = our_serializer.serialized_json }.real * 1000
        ams_time = Benchmark.measure { ams_json = ams_serializer.to_json }.real * 1000
        print_stats(movie_count, ams_time, our_time)
        expect(our_json.length).to eq ams_json.length
        expect { our_serializer.serialized_json }.to perform_faster_than { ams_serializer.to_json }.at_least(speed_factor).times
      end
    end
  end
end