module EasyLog

# File lib/easy_log.rb, line 7
def self.included cls
  cls.extend EasyLog
end

# File lib/easy_log.rb, line 19
def self.logger
  @logger ||= (defined?(Rails) ? Rails.logger : Logger.new(STDOUT))
end

# File lib/easy_log.rb, line 11
def self.set_logger(logger)
  if logger.respond_to? :info
    @logger = logger
  else
    fail InvalidLoggerError, 'Logger must respond to info!'
  end
end

# File lib/easy_log.rb, line 23
def log(*args)
  @current_binding = binding.of_caller(1)
  EasyLog.logger.info msg(*args)
end

# File lib/easy_log.rb, line 28
def msg(*args)
  @current_binding = binding.of_caller(1) unless @current_binding
  types = [:start, :finish, :success, :info, :warning, :error]
  requires_message = {
    start: false,
    finish: false,
    success: false,
    info: true,
    warning: true,
    error: true
  }
  type = args.shift if args.first.is_a?(Symbol) && types.include?(args.first)
  message = args.shift if args.first.is_a?(String)
  additional_params = args.shift

  if requires_message[type] && !message
    fail(ArgumentError, "message required for #{type}")
  end

  display_type = "#{type.to_s.upcase}#{message ? ': ' : '!'}" if type

  param_string = build_params_string(
    instance_params,
    method_params,
    additional_params
  )

  "#{class_method_string}: #{display_type}#{message}#{param_string}"
end

# File lib/easy_log.rb, line 87
def build_params_string(instance, method, additional)
  full_hash = instance.to_h.merge(method.to_h).merge(additional.to_h)
  params_string = full_hash.inject('') do |a, (k, v)|
    a += " #{k}: #{v}"
  end

  " w/#{params_string}" unless params_string.nil? || params_string == ''
end

# File lib/easy_log.rb, line 61
def class_method_string
  full_str = @current_binding.eval('method(__method__).to_s')
  full_str.sub('#<Method: ', '').sub(/>$/, '')
end

# File lib/easy_log.rb, line 76
def instance_params
  @current_binding.eval('instance_variables').inject({}) do |a, param|
    unless [:@current_binding, :@logger].include?(param)
      value = @current_binding.eval(param.to_s)
      a[param] = value if value
    end
    a
  end
end

# File lib/easy_log.rb, line 67
def method_params
  params_method = 'method(__method__).parameters'
  @current_binding.eval(params_method).inject({}) do |a, param|
    value = @current_binding.eval(param.last.to_s)
    a[param.last.to_s] = value if value
    a
  end
end