# frozen_string_literal: true

require "d_heap"
require "ostruct"

# Different benchmark scenarios and implementations to benchmark
module DHeap::Benchmarks

  def self.puts_version_info(type = "Benchmark", io = $stdout)
    io.puts "#{type} run at %s" % [Time.now]
    io.puts "ruby v%s, DHeap v%s" % [RUBY_VERSION, DHeap::VERSION]
    io.puts
  end

  # rubocop:disable Style/NumericPredicate

  # moves "rand" outside the benchmarked code, to avoid measuring that too.
  module Randomness

    def default_randomness_size; 1_000_000 end

    def fill_random_vals(target_size = default_randomness_size, io: $stdout)
      @dheap_bm_random_vals ||= []
      count = target_size - @dheap_bm_random_vals.length
      return 0 if count <= 0
      millions = (count / 1_000_000.0).round(3)
      io&.puts "~~~~~~ filling @dheap_bm_random_vals with #{millions}M ~~~~~~"
      io&.flush
      count.times do @dheap_bm_random_vals << rand(0..10_000) end
      @dheap_bm_random_len = @dheap_bm_random_vals.length
      @dheap_bm_random_idx = (((@dheap_bm_random_idx || -1) + 1) % @dheap_bm_random_len)
      nil
    end

    def random_val
      @dheap_bm_random_vals.fetch(
        @dheap_bm_random_idx = ((@dheap_bm_random_idx + 1) % @dheap_bm_random_len)
      )
    end

  end

  # different scenarios to be benchmarked or profiled
  module Scenarios

    def push_n_multiple_queues(count, *queues)
      while 0 < count
        value = @dheap_bm_random_vals.fetch(
          @dheap_bm_random_idx = ((@dheap_bm_random_idx + 1) % @dheap_bm_random_len)
        )
        queues.each do |queue|
          queue << value
        end
        count -= 1
      end
    end

    def push_n(queue, count)
      while 0 < count
        queue << @dheap_bm_random_vals.fetch(
          @dheap_bm_random_idx = ((@dheap_bm_random_idx + 1) % @dheap_bm_random_len)
        )
        count -= 1
      end
    end

    def push_n_then_pop_n(queue, count) # rubocop:disable Metrics/MethodLength
      i = 0
      while i < count
        queue << @dheap_bm_random_vals.fetch(
          @dheap_bm_random_idx = ((@dheap_bm_random_idx + 1) % @dheap_bm_random_len)
        )
        i += 1
      end
      while 0 < i
        queue.pop
        i -= 1
      end
    end

    def repeated_push_pop(queue, count)
      while 0 < count
        queue << @dheap_bm_random_vals.fetch(
          @dheap_bm_random_idx = ((@dheap_bm_random_idx + 1) % @dheap_bm_random_len)
        )
        queue.pop
        count -= 1
      end
    end

  end

  include Randomness
  include Scenarios

  def initq(klass, count = 0)
    queue = klass.new
    while 0 < count
      queue << @dheap_bm_random_vals.fetch(
        @dheap_bm_random_idx = ((@dheap_bm_random_idx + 1) % @dheap_bm_random_len)
      )
      count -= 1
    end
    queue
  end

  # rubocop:enable Style/NumericPredicate

  require "d_heap/benchmarks/implementations"

end