require 'uri'
require 'json/add/regexp'
require 'pact/logging'
require 'pact/consumer/mock_service_client'
require_relative 'interactions_filter'

module Pact
  module Consumer

    class ConsumerContractBuilder

      include Pact::Logging

      attr_reader :consumer_contract, :mock_service_base_url

      def initialize(attributes)
        @interaction_builder = nil
        @mock_service_client = MockServiceClient.new(attributes[:provider_name], attributes[:port])
        @consumer_contract = Pact::ConsumerContract.new(
          :consumer => ServiceConsumer.new(name: attributes[:consumer_name]),
          :provider => ServiceProvider.new(name: attributes[:provider_name])
          )
        @consumer_contract.interactions = interactions_for_new_consumer_contract(attributes[:pactfile_write_mode])
        @interactions_filter = filter(@consumer_contract.interactions, attributes[:pactfile_write_mode])
        @mock_service_base_url = "http://localhost:#{attributes[:port]}"
      end

      def given(provider_state)
        interaction_builder.given(provider_state)
      end

      def upon_receiving(description)
        interaction_builder.upon_receiving(description)
      end

      def interaction_builder
        @interaction_builder ||=
        begin
          interaction_builder = InteractionBuilder.new
          interaction_builder.on_interaction_fully_defined do | interaction |
            self.handle_interaction_fully_defined(interaction)
          end
          interaction_builder
        end
      end

      def verify example_description
        mock_service_client.verify example_description
      end

      def log msg
        mock_service_client.log msg
      end

      def wait_for_interactions options
        wait_max_seconds = options.fetch(:wait_max_seconds, 3)
        poll_interval = options.fetch(:poll_interval, 0.1)
        mock_service_client.wait_for_interactions wait_max_seconds, poll_interval
      end

      def handle_interaction_fully_defined interaction
        interactions_filter << interaction
        mock_service_client.add_expected_interaction interaction #TODO: What will happen if duplicate added?
        consumer_contract.update_pactfile
        self.interaction_builder = nil
      end

      private

      attr_reader :mock_service_client
      attr_reader :interactions_filter
      attr_writer :interaction_builder

      def interactions_for_new_consumer_contract pactfile_write_mode
        pactfile_write_mode == :update ? existing_interactions : []
      end

      def filter interactions, pactfile_write_mode
        if pactfile_write_mode == :update
          UpdatableInteractionsFilter.new(interactions)
        else
          DistinctInteractionsFilter.new(interactions)
        end
      end

      def warn_and_stderr msg
        $stderr.puts msg
        logger.warn msg
      end

      def info_and_puts msg
        $stdout.puts msg
        logger.info msg
      end

      def existing_interactions
        interactions = []
        if pactfile_exists?
          begin
            interactions = existing_consumer_contract.interactions
            info_and_puts "*****************************************************************************"
            info_and_puts "Updating existing file .#{consumer_contract.pactfile_path.gsub(Dir.pwd, '')} as config.pactfile_write_mode is :update"
            info_and_puts "Only interactions defined in this test run will be updated."
            info_and_puts "As interactions are identified by description and provider state, pleased note that if either of these have changed, the old interactions won't be removed from the pact file until the specs are next run with :pactfile_write_mode => :overwrite."
            info_and_puts "*****************************************************************************"
          rescue StandardError => e
            warn_and_stderr "Could not load existing consumer contract from #{consumer_contract.pactfile_path} due to #{e}"
            warn_and_stderr "Creating a new file."
          end
        end
        interactions
      end

      def pactfile_exists?
        File.exist?(consumer_contract.pactfile_path)
      end

      def existing_consumer_contract
        Pact::ConsumerContract.from_uri(consumer_contract.pactfile_path)
      end

    end
  end
end