class RSpec::Core::Bisect::ExampleMinimizer

def abort_if_ordering_inconsistent(results)
  expected_order = all_example_ids & results.all_example_ids
  return if expected_order == results.all_example_ids
  raise BisectFailedError, "\n\nThe example ordering is inconsistent. " \
        "`--bisect` relies upon consistent ordering (e.g. by passing " \
        "`--seed` if you're using random ordering) to work properly."
end

def bisect_round(round)
  value, duration = track_duration do
    subsets = SubsetEnumerator.new(remaining_ids)
    notify(:bisect_round_started, :round => round,
                                  :subset_size => subsets.subset_size,
                                  :remaining_count => remaining_ids.size)
    yield subsets
  end
  notify(:bisect_round_finished, :duration => duration, :round => round)
  value
end

def currently_needed_ids
  remaining_ids + failed_example_ids
end

def each_bisect_round(&block)
  last_round, duration = track_duration do
    1.upto(INFINITY) do |round|
      break if :done == bisect_round(round, &block)
    end
  end
  notify(:bisect_complete, :round => last_round, :duration => duration,
                           :original_non_failing_count => non_failing_example_ids.size,
                           :remaining_count => remaining_ids.size)
end

def find_minimal_repro
  prep
  self.remaining_ids = non_failing_example_ids
  each_bisect_round do |subsets|
    ids_to_ignore = subsets.find do |ids|
      get_expected_failures_for?(remaining_ids - ids)
    end
    next :done unless ids_to_ignore
    self.remaining_ids -= ids_to_ignore
    notify(:bisect_ignoring_ids, :ids_to_ignore => ids_to_ignore, :remaining_ids => remaining_ids)
  end
  currently_needed_ids
end

def get_expected_failures_for?(ids)
  ids_to_run = ids + failed_example_ids
  notify(:bisect_individual_run_start, :command => runner.repro_command_from(ids_to_run))
  results, duration = track_duration { runner.run(ids_to_run) }
  notify(:bisect_individual_run_complete, :duration => duration, :results => results)
  abort_if_ordering_inconsistent(results)
  (failed_example_ids & results.failed_example_ids) == failed_example_ids
end

def initialize(runner, reporter)
  @runner   = runner
  @reporter = reporter
end

def non_failing_example_ids
  @non_failing_example_ids ||= all_example_ids - failed_example_ids
end

def notify(*args)
  reporter.publish(*args)
end

def prep
  notify(:bisect_starting, :original_cli_args => runner.original_cli_args)
  _, duration = track_duration do
    original_results    = runner.original_results
    @all_example_ids    = original_results.all_example_ids
    @failed_example_ids = original_results.failed_example_ids
  end
  if @failed_example_ids.empty?
    raise BisectFailedError, "\n\nNo failures found. Bisect only works " \
          "in the presence of one or more failing examples."
  else
    notify(:bisect_original_run_complete, :failed_example_ids => failed_example_ids,
                                          :non_failing_example_ids => non_failing_example_ids,
                                          :duration => duration)
  end
end

def repro_command_for_currently_needed_ids
  return runner.repro_command_from(currently_needed_ids) if remaining_ids
  "(Not yet enough information to provide any repro command)"
end

def track_duration
  start = ::RSpec::Core::Time.now
  [yield, ::RSpec::Core::Time.now - start]
end