class Appraisal::Command

def announce
  if gemfile
    puts ">> BUNDLE_GEMFILE=#{gemfile} #{command_as_string}"
  else
    puts ">> #{command_as_string}"
  end
end

def command_as_string
  if command.is_a?(Array)
    Shellwords.join(command)
  else
    command
  end
end

def command_starting_with_bundle(original_command)
  if command_starts_with_bundle?(original_command)
    original_command
  else
    %w(bundle exec) + original_command
  end
end

def command_starts_with_bundle?(original_command)
  if original_command.is_a?(Array)
    original_command.first =~ /^bundle/
  else
    original_command =~ /^bundle/
  end
end

def ensure_bundler_is_available
  version = Utils.bundler_version
  unless system %(gem list --silent -i bundler -v #{version})
    puts ">> Reinstall Bundler into #{ENV["GEM_HOME"]}"
    unless system "gem install bundler --version #{version}"
      puts
      puts <<-ERROR.strip.gsub(/\s+/, " ")
        Bundler installation failed.
        Please try running:
          `GEM_HOME="#{ENV["GEM_HOME"]}" gem install bundler --version #{version}`
        manually.
      ERROR
      exit(1)
    end
  end
end

def initialize(command, options = {})
  @gemfile = options[:gemfile]
  @env = options.fetch(:env, {})
  @command = command_starting_with_bundle(command)
end

def run
  run_env = test_environment.merge(env)
  Bundler.with_original_env do
    ensure_bundler_is_available
    announce
    ENV["BUNDLE_GEMFILE"] = gemfile
    ENV["APPRAISAL_INITIALIZED"] = "1"
    run_env.each_pair do |key, value|
      ENV[key] = value
    end
    unless Kernel.system(command_as_string)
      exit(1)
    end
  end
end

def test_environment
  return {} unless ENV["APPRAISAL_UNDER_TEST"] == "1"
  {
    "GEM_HOME" => ENV["GEM_HOME"],
    "GEM_PATH" => "",
  }
end