require "abstract_unit"
require "securerandom"

# You need to start a memcached server inorder to run these tests
class MemCacheStoreTest < ActionDispatch::IntegrationTest
  class TestController < ActionController::Base
    def no_session_access
      head :ok
    end

    def set_session_value
      session[:foo] = "bar"
      head :ok
    end

    def set_serialized_session_value
      session[:foo] = SessionAutoloadTest::Foo.new
      head :ok
    end

    def get_session_value
      render plain: "foo: #{session[:foo].inspect}"
    end

    def get_session_id
      render plain: "#{request.session.id}"
    end

    def call_reset_session
      session[:bar]
      reset_session
      session[:bar] = "baz"
      head :ok
    end
  end

  begin
    require "dalli"
    ss = Dalli::Client.new("localhost:11211").stats
    raise Dalli::DalliError unless ss["localhost:11211"]

    def test_setting_and_getting_session_value
      with_test_route_set do
        get "/set_session_value"
        assert_response :success
        assert cookies["_session_id"]

        get "/get_session_value"
        assert_response :success
        assert_equal 'foo: "bar"', response.body
      end
    rescue Dalli::RingError => ex
      skip ex.message, ex.backtrace
    end

    def test_getting_nil_session_value
      with_test_route_set do
        get "/get_session_value"
        assert_response :success
        assert_equal "foo: nil", response.body
      end
    rescue Dalli::RingError => ex
      skip ex.message, ex.backtrace
    end

    def test_getting_session_value_after_session_reset
      with_test_route_set do
        get "/set_session_value"
        assert_response :success
        assert cookies["_session_id"]
        session_cookie = cookies.send(:hash_for)["_session_id"]

        get "/call_reset_session"
        assert_response :success
        assert_not_equal [], headers["Set-Cookie"]

        cookies << session_cookie # replace our new session_id with our old, pre-reset session_id

        get "/get_session_value"
        assert_response :success
        assert_equal "foo: nil", response.body, "data for this session should have been obliterated from memcached"
      end
    rescue Dalli::RingError => ex
      skip ex.message, ex.backtrace
    end

    def test_getting_from_nonexistent_session
      with_test_route_set do
        get "/get_session_value"
        assert_response :success
        assert_equal "foo: nil", response.body
        assert_nil cookies["_session_id"], "should only create session on write, not read"
      end
    rescue Dalli::RingError => ex
      skip ex.message, ex.backtrace
    end

    def test_setting_session_value_after_session_reset
      with_test_route_set do
        get "/set_session_value"
        assert_response :success
        assert cookies["_session_id"]
        session_id = cookies["_session_id"]

        get "/call_reset_session"
        assert_response :success
        assert_not_equal [], headers["Set-Cookie"]

        get "/get_session_value"
        assert_response :success
        assert_equal "foo: nil", response.body

        get "/get_session_id"
        assert_response :success
        assert_not_equal session_id, response.body
      end
    rescue Dalli::RingError => ex
      skip ex.message, ex.backtrace
    end

    def test_getting_session_id
      with_test_route_set do
        get "/set_session_value"
        assert_response :success
        assert cookies["_session_id"]
        session_id = cookies["_session_id"]

        get "/get_session_id"
        assert_response :success
        assert_equal session_id, response.body, "should be able to read session id without accessing the session hash"
      end
    rescue Dalli::RingError => ex
      skip ex.message, ex.backtrace
    end

    def test_deserializes_unloaded_class
      with_test_route_set do
        with_autoload_path "session_autoload_test" do
          get "/set_serialized_session_value"
          assert_response :success
          assert cookies["_session_id"]
        end
        with_autoload_path "session_autoload_test" do
          get "/get_session_id"
          assert_response :success
        end
      end
    rescue Dalli::RingError => ex
      skip ex.message, ex.backtrace
    end

    def test_doesnt_write_session_cookie_if_session_id_is_already_exists
      with_test_route_set do
        get "/set_session_value"
        assert_response :success
        assert cookies["_session_id"]

        get "/get_session_value"
        assert_response :success
        assert_nil headers["Set-Cookie"], "should not resend the cookie again if session_id cookie is already exists"
      end
    rescue Dalli::RingError => ex
      skip ex.message, ex.backtrace
    end

    def test_prevents_session_fixation
      with_test_route_set do
        get "/get_session_value"
        assert_response :success
        assert_equal "foo: nil", response.body
        session_id = cookies["_session_id"]

        reset!

        get "/set_session_value", params: { _session_id: session_id }
        assert_response :success
        assert_not_equal session_id, cookies["_session_id"]
      end
    rescue Dalli::RingError => ex
      skip ex.message, ex.backtrace
    end
  rescue LoadError, RuntimeError, Dalli::DalliError
    $stderr.puts "Skipping MemCacheStoreTest tests. Start memcached and try again."
  end

  private
    def with_test_route_set
      with_routing do |set|
        set.draw do
          ActiveSupport::Deprecation.silence do
            get ":action", to: ::MemCacheStoreTest::TestController
          end
        end

        @app = self.class.build_app(set) do |middleware|
          middleware.use ActionDispatch::Session::MemCacheStore, key: "_session_id", namespace: "mem_cache_store_test:#{SecureRandom.hex(10)}"
          middleware.delete ActionDispatch::ShowExceptions
        end

        yield
      end
    end
end
