class Facter::Log

def colorize(msg, color)
  "#{color}#{msg}#{RESET}"
end

def debug(msg)
  return unless debugging_active?
  if @@message_callback && Options[:allow_external_loggers]
    @@message_callback.call(:debug, msg)
  else
    msg = colorize(msg, CYAN) if Options[:color]
    @@logger.debug(@class_name + ' - ' + msg)
  end
end

def debugging_active?
  return true unless Facter.respond_to?(:debugging?)
  Facter.debugging?
end

def empty_message_error(msg)
  invoker = caller(1..1).first.slice(/.*:\d+/)
  @@logger.warn "#{self.class}#debug invoked with invalid message #{msg.inspect}:#{msg.class} at #{invoker}"
end

def error(msg, colorize = false)
  @@has_errors = true
  if @@message_callback && Options[:allow_external_loggers]
    @@message_callback.call(:error, msg)
  else
    msg = colorize(msg, RED) if colorize || Options[:color]
    @@logger.error(@class_name + ' - ' + msg)
  end
end

def errors?
  @@has_errors
end

def info(msg)
  if msg.nil? || msg.empty?
    empty_message_error(msg)
  elsif @@message_callback && Options[:allow_external_loggers]
    @@message_callback.call(:info, msg)
  else
    msg = colorize(msg, GREEN) if Options[:color]
    @@logger.info(@class_name + ' - ' + msg)
  end
end

def initialize(logged_class)
  @class_name = LoggerHelper.determine_callers_name(logged_class)
  return unless @@logger.nil?
  @@logger = Logger.new(STDOUT)
  @@logger.level = DEFAULT_LOG_LEVEL
end

def level
  @@logger.level
end

def level=(log_level)
  @@logger.level = log_level
end

def log_exception(exception)
  msg = exception.message
  msg += "\n" + exception.backtrace.join("\n") if Options[:trace]
  error(msg, true)
end

def on_message(&block)
  @@message_callback = block
end

def output(output)
  return if @@logger
  @@logger = Logger.new(output)
  set_logger_format
  @@logger.level = DEFAULT_LOG_LEVEL
end

def set_logger_format
  @@logger.formatter = proc do |severity, datetime, _progname, msg|
    datetime = datetime.strftime(@datetime_format || '%Y-%m-%d %H:%M:%S.%6N ')
    "[#{datetime}] #{severity} #{msg} \n"
  end
end

def warn(msg)
  if @@message_callback && Options[:allow_external_loggers]
    @@message_callback.call(:warn, msg)
  else
    msg = colorize(msg, YELLOW) if Options[:color]
    @@logger.warn(@class_name + ' - ' + msg)
  end
end