require 'dry-equalizer'

module Messaging
  module Routing
    # Internal: Used by routing to match a pattern against a callable (handler)
    class Route
      include Dry::Equalizer(:matcher, :handler)

      attr_reader :matcher
      attr_reader :handler

      def initialize(pattern, handler)
        @matcher = MessageMatcher.new(pattern: pattern)
        @handler = handler
        verify_handler!
      end

      def call(message, context = self)
        return unless @matcher.matches?(message)

        context.instance_exec(message, &@handler)
      end

      def topics
        matcher.topics
      end

      private

      def verify_handler!
        raise ArgumentError, 'Handler must be callable' unless handler.respond_to? :call
      end
    end
  end
end