module Fluent

  # 1. patch to avoid writing the configuration dump
  #   until suppress config dump option will be supported.
  #   https://github.com/fluent/fluentd/pull/186
  # 2. patch to support custom depth_offset
  class Log
    # This is used for checking if patched
    # flydata-core/logger.rb uses this
    attr_accessor :flydata_patched

    def trace(*args, &block)
      return if @level > LEVEL_TRACE
      args << block.call if block
      depth_offset = extract_depth_offset(args)
      time, msg = event(:trace, args)
      puts [@color_trace, caller_line(time, depth_offset, LEVEL_TRACE), msg, @color_reset].join
    rescue
      # logger should not raise an exception. This rescue prevents unexpected behaviour.
    end

    def debug(*args, &block)
      return if @level > LEVEL_DEBUG
      args << block.call if block
      depth_offset = extract_depth_offset(args)
      time, msg = event(:debug, args)
      puts [@color_debug, caller_line(time, depth_offset, LEVEL_DEBUG), msg, @color_reset].join
    rescue
    end

    def warn(*args, &block)
      return if @level > LEVEL_WARN
      args << block.call if block
      depth_offset = extract_depth_offset(args)
      time, msg = event(:warn, args)
      if msg and m = /^parameter '(?<param>[^']+)' in/.match(msg.strip)
        msg = "parameter '#{m[:param]}' is not used."
      end
      puts [@color_warn, caller_line(time, depth_offset, LEVEL_WARN), msg, @color_reset].join
    rescue
    end

    def info(*args, &block)
      return if @level > LEVEL_INFO
      args << block.call if block
      depth_offset = extract_depth_offset(args)
      time, msg = event(:info, args)
      puts [@color_info, caller_line(time, depth_offset, LEVEL_INFO), msg, @color_reset].join
    rescue
    end

    def error(*args, &block)
      return if @level > LEVEL_ERROR
      args << block.call if block
      depth_offset = extract_depth_offset(args)
      time, msg = event(:error, args)
      puts [@color_error, caller_line(time, depth_offset, LEVEL_ERROR), msg, @color_reset].join
    rescue
    end

    private

    def extract_depth_offset(args)
      opt = args.last
      if opt.kind_of?(Hash) and opt[:depth_offset].kind_of?(Integer)
        return opt.delete(:depth_offset)
      end
      @depth_offset
    end
  end

end