# encoding: utf-8

module Punchblock
  module Component
    class Input < ComponentNode
      NLSML_NAMESPACE = 'http://www.ietf.org/xml/ns/mrcpv2'

      register :input, :input

      # @return [Integer] the amount of time in milliseconds that an input command will wait until considered that a silence becomes a NO-MATCH
      attribute :max_silence, Integer

      # @return [Float] Confidence with which to consider a response acceptable
      attribute :min_confidence, Float

      # @return [Symbol] mode by which to accept input. Can be :voice, :dtmf or :any
      attribute :mode, Symbol, default: :dtmf

      # @return [String] recognizer to use for speech recognition
      attribute :recognizer, String

      # @return [String] language to use for speech recognition
      attribute :language, String

      # @return [String] terminator by which to signal the end of input
      attribute :terminator, String

      # @return [Float] Indicates how sensitive the interpreter should be to loud versus quiet input. Higher values represent greater sensitivity.
      attribute :sensitivity, Float

      # @return [Integer] Indicates the amount of time preceding input which may expire before a timeout is triggered.
      attribute :initial_timeout, Integer

      # @return [Integer] Indicates (in the case of DTMF input) the amount of time between input digits which may expire before a timeout is triggered.
      attribute :inter_digit_timeout, Integer

      attribute :grammars, Array, default: []
      def grammars=(others)
        super others.map { |other| Grammar.new(other) }
      end

      ##
      # @param [Hash] other
      # @option other [String] :content_type the document content type
      # @option other [String] :value the grammar doucment
      # @option other [String] :url the url from which to fetch the grammar
      #
      def grammar=(other)
        self.grammars = [other].compact
      end

      def inherit(xml_node)
        grammar_nodes = xml_node.xpath('ns:grammar', ns: self.class.registered_ns)
        self.grammars = grammar_nodes.to_a.map { |grammar_node| Grammar.from_xml(grammar_node)}
        super
      end

      def rayo_attributes
        {
          'max-silence' => max_silence,
          'min-confidence' => min_confidence,
          'mode' => mode,
          'recognizer' => recognizer,
          'language' => language,
          'terminator' => terminator,
          'sensitivity' => sensitivity,
          'initial-timeout' => initial_timeout,
          'inter-digit-timeout' => inter_digit_timeout
        }
      end

      def rayo_children(root)
        grammars.each do |grammar|
          grammar.to_rayo(root)
        end
        super
      end

      class Grammar < RayoNode
        register :grammar, :input

        GRXML_CONTENT_TYPE = 'application/srgs+xml'

        attribute :value
        attribute :content_type, String, default: ->(grammar, attribute) { grammar.url ? nil : GRXML_CONTENT_TYPE }
        attribute :url

        def inherit(xml_node)
          self.value = xml_node.content.strip
          super
        end

        def rayo_attributes
          {
            'url' => url,
            'content-type' => content_type
          }
        end

        def rayo_children(root)
          root.cdata value
        end

        private

        def grxml?
          content_type == GRXML_CONTENT_TYPE
        end
      end

      class Complete
        class Match < Event::Complete::Reason
          register :match, :input_complete

          attribute :content_type, String, default: 'application/nlsml+xml'

          attribute :nlsml
          def nlsml=(other)
            doc = case other
            when Nokogiri::XML::Element, Nokogiri::XML::Document
              RubySpeech::NLSML::Document.new(other)
            else
              other
            end
            super doc
          end

          def mode
            nlsml.best_interpretation[:input][:mode]
          end

          def confidence
            nlsml.best_interpretation[:confidence]
          end

          def utterance
            nlsml.best_interpretation[:input][:content]
          end

          def interpretation
            nlsml.best_interpretation[:instance]
          end

          def inherit(xml_node)
            self.nlsml = result_node(xml_node)
            super
          end

          private

          def result_node(xml)
            directly_nested = xml.at_xpath 'ns:result', ns: NLSML_NAMESPACE
            return directly_nested if directly_nested
            document = Nokogiri::XML.parse xml.text, nil, nil, Nokogiri::XML::ParseOptions::NOBLANKS
            document.at_xpath 'ns:result', ns: NLSML_NAMESPACE or raise "Couldn't find the NLSML node"
          end
        end

        class NoMatch < Event::Complete::Reason
          register :nomatch, :input_complete
        end

        class NoInput < Event::Complete::Reason
          register :noinput, :input_complete
        end
      end
    end
  end
end