class Cucumber::Ast::Tags

def accept(visitor)
  return if Cucumber.wants_to_quit
  @tag_names.each do |tag_name|
    visitor.visit_tag_name(tag_name)
  end
end

def accept_hook?(hook)
  self.class.matches?(@tag_names, hook.tag_name_lists)
end

def check_at_sign_prefix(tag_names)
  tag_names.each{|tag_name| raise "Tag names must start with an @ sign. The following tag name didn't: #{tag_name.inspect}" unless tag_name[0..0] == '@'}
end

def check_if_tags_match(source_tag_names, tag_name_lists)
  tag_exp = Or.new(tag_name_lists.map{|tag_name_list| And.new(tag_name_list) })
  tag_exp.matches?(source_tag_names)
end

def count(tag)
  # See discussion:
  # http://github.com/weplay/cucumber/commit/2dc592acdf3f7c1a0c333a8164649936bb82d983
  if @tag_names.respond_to?(:count) && @tag_names.method(:count).arity > 0
    @tag_names.count(tag) # 1.9
  else
    @tag_names.select{|t| t == tag}.length  # 1.8
  end
end

def exclude_tag?(tag_name)
  tag_name =~ EXCLUDE_PATTERN
end

def initialize(line, tag_names)
  @line, @tag_names = line, tag_names
end

def matches?(source_tag_names, tag_name_lists)
  validate_tags(tag_name_lists)
  tag_name_lists.empty? ? true : check_if_tags_match(source_tag_names, tag_name_lists)
end

def parse_tags(tags_string)
  tags_string.split(',')
end

def strip_negative_char(tag_names)
  tag_names.map{|name| name[1..-1]}
end

def to_sexp
  @tag_names.map{|tag_name| [:tag, tag_name]}
end

def validate_tags(tag_name_lists)
  all_tag_names = tag_name_lists.flatten
  exclude_tag_names, include_tag_names = all_tag_names.partition{|tag_name| exclude_tag?(tag_name)}
  exclude_tag_names = strip_negative_char(exclude_tag_names)
  check_at_sign_prefix(exclude_tag_names + include_tag_names)
end