class Byebug::HelpCommand

def description
  <<-EOD
    h[elp][ <cmd>[ <subcmd>]]
    help                -- prints this help.
    help <cmd>          -- prints help on command <cmd>.
    help <cmd> <subcmd> -- prints help on <cmd>'s subcommand <subcmd>.
  EOD
end

def execute
  return puts(help) unless @match[1]
  cmd = Byebug.commands.find { |c| c.to_name == @match[1] }
  return errmsg(pr('help.errors.undefined', cmd: @match[1])) unless cmd
  cmd = cmd.new(@state)
  return puts(cmd.help) unless @match[2]
  subcmd = cmd.subcommands.find(@match[2])
  return errmsg(pr('help.errors.undefined', cmd: @match[2])) unless subcmd
  puts(subcmd.help)
end

def regexp
  /^\s* h(?:elp)? (?:\s+(\S+))? (?:\s+(\S+))? \s*$/x
end