#!/usr/bin/env ruby
$:.unshift File.expand_path('../lib', __dir__)

require 'benchmark/driver'
require 'benchmark/driver/bundle_installer'
require 'benchmark/driver/yaml_parser'
require 'optparse'
require 'yaml'

#
# Parse command line options
#
options = {}
parser = OptionParser.new do |o|
  o.banner = "Usage: #{File.basename($0, '.*')} [options] [YAML]"
  o.on('-e', '--executables [EXECS]', 'Ruby executables (e1::path1,arg1,...; e2::path2,arg2;...)') do |e|
    abort '-e, --executable must take argument but not given' if e.nil?
    options[:execs] ||= []
    e.split(';').each do |name_path|
      name, path = name_path.split('::', 2)
      options[:execs] << Benchmark::Driver::Configuration::Executable.new(name, path ? path.split(',') : [name])
    end
  end
  o.on('--rbenv [VERSIONS]', 'Ruby executables in rbenv (x.x.x,arg1,...;y.y.y,arg2,...;...)') do |r|
    abort '--rbenv must take argument but not given' if r.nil?
    options[:execs] ||= []
    r.split(';').each do |spec|
      version, *args = spec.split(',')
      path = `RBENV_VERSION='#{version}' rbenv which ruby`.rstrip
      abort "Failed to execute 'rbenv which ruby'" unless $?.success?
      options[:execs] << Benchmark::Driver::Configuration::Executable.new(version, [path, *args])
    end
  end
  o.on('-o', '--output [TYPE]', 'Specify output type (ips, time, memory, markdown)') do |t|
    abort '-o, --output must take argument but not given' if t.nil?
    options[:output] = t
  end
  o.on('-c', '--compare', 'Compare results (currently only supported in ips output)') do |v|
    options[:compare] = v
  end
  o.on('-r', '--repeat-count [NUM]', 'Try benchmark NUM times and use the fastest result') do |v|
    begin
      options[:repeat_count] = Integer(v)
    rescue ArgumentError
      abort "-r, --repeat-count must take Integer, but got #{v.inspect}"
    end
  end
  o.on('--filter [REGEXP]', 'Filter out benchmarks with given regexp') do |v|
    abort '--filter can be used only once' if options.key?(:filter)
    options[:filter] = v
  end
  o.on('--bundler', 'Install and use gems specified in Gemfile') do |v|
    options[:bundler] = v
  end
  o.on('--dir', 'Override __dir__ from "/tmp" to actual directory of YAML') do |v|
    options[:dir] = v
  end
end
args = parser.parse!(ARGV)
if args.empty?
  abort "No YAML file is specified!\n\n#{parser.help}"
end

#
# Parse benchmark definitions
#
jobs = args.flat_map do |path|
  yaml = YAML.load(File.read(path))
  Benchmark::Driver::Configuration.symbolize_keys!(yaml)

  begin
    Benchmark::Driver::YamlParser.parse(yaml)
  rescue ArgumentError
    $stderr.puts "benchmark-driver: Failed to parse #{yaml.dump}."
    $stderr.puts '  YAML format may be wrong. See error below:'
    $stderr.puts
    raise
  end
end

#
# Proceed parsed options
#
config = Benchmark::Driver::Configuration.new(jobs)
config.runner_options = Benchmark::Driver::Configuration::RunnerOptions.new(:exec)
config.output_options = Benchmark::Driver::Configuration::OutputOptions.new(:ips)

if options.key?(:execs)
  # Proceed execs first for --bundler
  config.runner_options.executables = options.delete(:execs)
end

options.each do |key, value|
  case key
  when :bundler
    config.runner_options.executables.each do |executable|
      Benchmark::Driver::BundleInstaller.bundle_install_for(executable)
      executable.command << '-rbundler/setup'
    end
  when :compare
    config.output_options.compare = value
  when :dir
    dir = File.dirname(path)
    config.jobs.each do |job|
      job.prelude = "__dir__ = #{dir.dump}.freeze; #{job.prelude}"
    end
  when :filter
    filter = Regexp.compile(value)
    config.jobs.select! do |job|
      job.name.match(filter)
    end
  when :output
    config.output_options.type = value.to_sym
  when :repeat_count
    config.runner_options.repeat_count = value
  else
    raise "Unhandled option: #{key.inspect}"
  end
end

Benchmark::Driver.run(config)