# this is vendored from cucumber-core gem with the module/class names changed
# in the 4.0 release of cucumber-core they removed support for legacy tags (~FC100)
# and we're not going to force everyone to redo their tags on a EOL product

module Foodcritic
  module Gherkin
    class TagExpression

      attr_reader :limits

      def initialize(tag_expressions)
        @ands = []
        @limits = {}
        tag_expressions.each do |expr|
          add(expr.strip.split(/\s*,\s*/))
        end
      end

      def empty?
        @ands.empty?
      end

      def evaluate(tags)
        return true if @ands.flatten.empty?
        vars = Hash[*tags.map{|tag| [tag.name, true]}.flatten]
        raise "No vars" if vars.nil? # Useless statement to prevent ruby warnings about unused var
        !!Kernel.eval(ruby_expression)
      end

    private

      def add(tags_with_negation_and_limits)
        negatives, positives = tags_with_negation_and_limits.partition{|tag| tag =~ /^~/}
        @ands << (store_and_extract_limits(negatives, true) + store_and_extract_limits(positives, false))
      end

      def store_and_extract_limits(tags_with_negation_and_limits, negated)
        tags_with_negation = []
        tags_with_negation_and_limits.each do |tag_with_negation_and_limit|
          tag_with_negation, limit = tag_with_negation_and_limit.split(':')
          tags_with_negation << tag_with_negation
          if limit
            tag_without_negation = negated ? tag_with_negation[1..-1] : tag_with_negation
            if @limits[tag_without_negation] && @limits[tag_without_negation] != limit.to_i
              raise "Inconsistent tag limits for #{tag_without_negation}: #{@limits[tag_without_negation]} and #{limit.to_i}"
            end
            @limits[tag_without_negation] = limit.to_i
          end
        end
        tags_with_negation
      end

      def ruby_expression
        "(" + @ands.map do |ors|
          ors.map do |tag|
            if tag =~ /^~(.*)/
              "!vars['#{$1}']"
            else
              "vars['#{tag}']"
            end
          end.join("||")
        end.join(")&&(") + ")"
      end
    end
  end
end