require 'cucumber/ast/has_steps'
require 'cucumber/ast/names'

module Cucumber
  module Ast
    class Scenario #:nodoc:
      include HasSteps
      include Names

      attr_reader :line

      class EmptyBackground
        def failed?
          false
        end

        def feature_elements
          []
        end

        def step_collection(step_invocations)
          StepCollection.new(step_invocations)
        end

        def init
        end
      end

      def initialize(background, comment, tags, line, keyword, title, description, raw_steps)
        @background = background || EmptyBackground.new
        @comment, @tags, @line, @keyword, @title, @description, @raw_steps = comment, tags, line, keyword, title, description, raw_steps
        @exception = @executed = nil
      end

      def init
        return if @steps
        @background.init
        @background.feature_elements << self
        attach_steps(@raw_steps)
        step_invocations = @raw_steps.map{|step| step.step_invocation}
        @steps = @background.step_collection(step_invocations)
      end

      def accept(visitor)
        return if Cucumber.wants_to_quit

        with_visitor(visitor) do
          visitor.visit_comment(@comment) unless @comment.empty?
          visitor.visit_tags(@tags)
          visitor.visit_scenario_name(@keyword, name, file_colon_line(@line), source_indent(first_line_length))

          skip_invoke! if @background.failed?
          visitor.runtime.with_hooks(self, skip_hooks?) do
            skip_invoke! if failed?
            visitor.visit_steps(@steps)
          end
          @executed = true
        end
      end

      # Returns true if one or more steps failed
      def failed?
        @steps.failed? || !!@exception
      end

      def fail!(exception)
        @exception = exception
        @current_visitor.visit_exception(@exception, :failed)
      end

      # Returns true if all steps passed
      def passed?
        !failed?
      end

      # Returns the first exception (if any)
      def exception
        @exception || @steps.exception
      end

      # Returns the status
      def status
        return :failed if @exception
        @steps.status
      end

      def skip_invoke!
        @steps.each{|step_invocation| step_invocation.skip_invoke!}
      end

      def to_sexp
        sexp = [:scenario, @line, @keyword, name]
        comment = @comment.to_sexp
        sexp += [comment] if comment
        tags = @tags.to_sexp
        sexp += tags if tags.any?
        steps = @steps.to_sexp
        sexp += steps if steps.any?
        sexp
      end


      def with_visitor(visitor)
        @current_visitor = visitor
        yield
        @current_visitor = nil
      end

      private

      def skip_hooks?
        @background.failed? || @executed
      end
    end
  end
end