require 'reek/smells/smell_detector'
require 'reek/smell_warning'

module Reek
  module Smells

    #
    # An Uncommunicative Name is a name that doesn't communicate its intent
    # well enough.
    # 
    # Poor names make it hard for the reader to build a mental picture
    # of what's going on in the code. They can also be mis-interpreted;
    # and they hurt the flow of reading, because the reader must slow
    # down to interpret the names.
    #
    # Currently +UncommunicativeModuleName+ checks for
    # * 1-character names
    # * names ending with a number
    #
    class UncommunicativeModuleName < SmellDetector

      SMELL_CLASS = 'UncommunicativeName'
      SMELL_SUBCLASS = self.name.split(/::/)[-1]
      MODULE_NAME_KEY = 'module_name'

      # The name of the config field that lists the regexps of
      # smelly names to be reported.
      REJECT_KEY = 'reject'

      DEFAULT_REJECT_SET = [/^.$/, /[0-9]$/]

      # The name of the config field that lists the specific names that are
      # to be treated as exceptions; these names will not be reported as
      # uncommunicative.
      ACCEPT_KEY = 'accept'

      DEFAULT_ACCEPT_SET = ['Inline::C']

      def self.default_config
        super.merge(
          REJECT_KEY => DEFAULT_REJECT_SET,
          ACCEPT_KEY => DEFAULT_ACCEPT_SET
        )
      end

      def self.contexts      # :nodoc:
        [:module, :class]
      end

      #
      # Checks the given +context+ for uncommunicative names.
      #
      # @return [Array<SmellWarning>]
      #
      # :reek:Duplication { allow_calls: [ to_s ] }
      def examine_context(ctx)
        @reject_names = value(REJECT_KEY, ctx, DEFAULT_REJECT_SET)
        @accept_names = value(ACCEPT_KEY, ctx, DEFAULT_ACCEPT_SET)
        exp = ctx.exp
        full_name = ctx.full_name
        name = exp.simple_name.to_s
        return [] if @accept_names.include?(full_name)
        var = name.gsub(/^[@\*\&]*/, '')
        return [] if @accept_names.include?(var)
        return [] unless @reject_names.detect {|patt| patt === var}
        smell = SmellWarning.new(SMELL_CLASS, full_name, [exp.line],
          "has the name '#{name}'",
          @source, SMELL_SUBCLASS, {MODULE_NAME_KEY => name})
        [smell]
      end
    end
  end
end