class BenchmarkDriver::Runner::CommandStdout

def execute(*args)
  stdout, stderr, status = Open3.capture3(*args)
  unless status.success?
    raise "Failed to execute: #{args.shelljoin} (status: #{$?.exitstatus}):\n[stdout]:\n#{stdout}\n[stderr]:\n#{stderr}"
  end
  stdout
end

def initialize(config:, output:, contexts:)
  @config = config
  @output = output
  @contexts = contexts
end

def parse(name:, command:, working_directory: nil, metrics_type:, stdout_to_metrics:)
  Job.new(
    name: name,
    command: command.shellsplit,
    working_directory: working_directory,
    metrics: parse_metrics(**metrics_type),
    stdout_to_metrics: stdout_to_metrics,
  )
end

def parse_metrics(unit:, name: nil, larger_better: nil, worse_word: nil)
  name ||= unit
  metric = BenchmarkDriver::Metric.new(
    name: name,
    unit: unit,
    larger_better: larger_better,
    worse_word: worse_word,
  )
  [metric]
end

def run(jobs)
  metric = jobs.first.metrics.first
  @output.with_benchmark do
    jobs.each do |job|
      @output.with_job(name: job.name) do
        @contexts.each do |context|
          exec = context.executable
          result = BenchmarkDriver::Repeater.with_repeat(config: @config, larger_better: metric.larger_better) do
            stdout = with_chdir(job.working_directory) do
              with_ruby_prefix(exec) { execute(*exec.command, *job.command) }
            end
            StdoutToMetrics.new(
              stdout: stdout,
              stdout_to_metrics: job.stdout_to_metrics,
            ).metrics_value
          end
          @output.with_context(name: exec.name, executable: exec) do
            @output.report(values: { metric => result.value }, all_values: { metric => result.all_values })
          end
        end
      end
    end
  end
end

def with_chdir(working_directory, &block)
  if working_directory
    Dir.chdir(working_directory) { block.call }
  else
    block.call
  end
end

def with_ruby_prefix(executable, &block)
  env = ENV.to_h.dup
  ENV['PATH'] = "#{File.dirname(executable.command.first)}:#{ENV['PATH']}"
  block.call
ensure
  ENV.replace(env)
end