# frozen_string_literal: true

require "logger"

module Kanal
  module Core
    module Logging
      #
      # Object of this class us used to store and use several loggers.
      # It inherits from standard Logger and overrides it's methods for accepting messages for every possible log level.
      # Calling #debug (or any other loglevel) on this object results in calling #debug for every logger that it stores.
      #
      class CompositeLogger < ::Logger
        # Property allowed_methods defines which methods can be called.
        # These methods mirror standard Logger methods.
        def initialize
          @loggers = []
        end

        def add_logger(logger)
          @loggers << logger
        end

        def debug(message)
          feed_message_to_loggers :debug, caller_class_name(caller.first), message
        end

        def info(message)
          feed_message_to_loggers :info, caller_class_name(caller.first), message
        end

        def warn(message)
          feed_message_to_loggers :warn, caller_class_name(caller.first), message
        end

        def error(message)
          feed_message_to_loggers :error, caller_class_name(caller.first), message
        end

        def fatal(message)
          feed_message_to_loggers :fatal, caller_class_name(caller.first), message
        end

        def unknown(message)
          feed_message_to_loggers :unknown, caller_class_name(caller.first), message
        end

        private

        def caller_class_name(caller)
          begin
            caller_class_name = "[" + caller.split(".rb").first.split("/").last.split('_').collect(&:capitalize).join + "]"
          rescue
            caller_class_name = "[ErrorGettingClassName]"
          end

          caller_class_name
        end

        def feed_message_to_loggers(method_name, caller_class_name, message)
          @loggers.each do |logger|
            # progname is a property of standard Logger. It is a prefix for log message.
            # In our case progname is used to store class name of class which calls for CompositeLogger methods.
            logger.progname = caller_class_name
            logger.send method_name, message
          end
        end
      end
    end
  end
end