class Bundler::CLI::Exec

def initialize(options, args)
  @options = options
  @cmd = args.shift
  @args = args
  @args << { close_others: !options.keep_file_descriptors? } unless Bundler.current_ruby.jruby?
end

def kernel_exec(*args)
  Kernel.exec(*args)
rescue Errno::EACCES, Errno::ENOEXEC
  Bundler.ui.error "bundler: not executable: #{cmd}"
  exit 126
rescue Errno::ENOENT
  Bundler.ui.error "bundler: command not found: #{cmd}"
  Bundler.ui.warn "Install missing gem executables with `bundle install`"
  exit 127
end

def kernel_load(file, *args)
  args.pop if args.last.is_a?(Hash)
  ARGV.replace(args)
  $0 = file
  Process.setproctitle(process_title(file, args)) if Process.respond_to?(:setproctitle)
  require_relative "../setup"
  TRAPPED_SIGNALS.each {|s| trap(s, "DEFAULT") }
  Kernel.load(file)
rescue SystemExit, SignalException
  raise
rescue Exception # rubocop:disable Lint/RescueException
  Bundler.ui.error "bundler: failed to load command: #{cmd} (#{file})"
  Bundler::FriendlyErrors.disable!
  raise
end

def process_title(file, args)
  "#{file} #{args.join(" ")}".strip
end

def ruby_shebang?(file)
  possibilities = [
    "#!/usr/bin/env ruby\n",
    "#!/usr/bin/env jruby\n",
    "#!/usr/bin/env truffleruby\n",
    "#!#{Gem.ruby}\n",
  ]
  if File.zero?(file)
    Bundler.ui.warn "#{file} is empty"
    return false
  end
  first_line = File.open(file, "rb") {|f| f.read(possibilities.map(&:size).max) }
  possibilities.any? {|shebang| first_line.start_with?(shebang) }
end

def run
  validate_cmd!
  SharedHelpers.set_bundle_environment
  if bin_path = Bundler.which(cmd)
    if !Bundler.settings[:disable_exec_load] && ruby_shebang?(bin_path)
      return kernel_load(bin_path, *args)
    end
    kernel_exec(bin_path, *args)
  else
    # exec using the given command
    kernel_exec(cmd, *args)
  end
end

def validate_cmd!
  return unless cmd.nil?
  Bundler.ui.error "bundler: exec needs a command to run"
  exit 128
end