require 'watir/wait/timer'

module Watir
  module Wait
    class TimeoutError < StandardError; end

    INTERVAL = 0.1

    class << self
      #
      # @!attribute timer
      #   Access Watir timer implementation in use.
      #   @see Timer
      #   @return [#wait]
      #

      attr_writer :timer

      def timer
        @timer ||= Timer.new
      end

      #
      # Waits until the block evaluates to true or times out.
      #
      # @example
      #   Watir::Wait.until { browser.text_field(name: "new_user_first_name").visible? }
      #
      # @param [Integer] timeout How long to wait in seconds
      # @param [String] message Message to raise if timeout is exceeded
      # @param [Object, NilClass] object Object to evaluate block against
      # @raise [TimeoutError] if timeout is exceeded
      #

      def until(timeout: nil, message: nil, interval: nil, object: nil)
        timeout ||= Watir.default_timeout
        run_with_timer(timeout, interval) do
          result = yield(object)
          return result if result
        end
        raise TimeoutError, message_for(timeout, object, message)
      end

      #
      # Wait while the block evaluates to true or times out.
      #
      # @example
      #   Watir::Wait.while { browser.text_field(name: "abrakadbra").present? }
      #
      # @param [Integer] timeout How long to wait in seconds
      # @param [String] message Message to raise if timeout is exceeded
      # @param [Object, NilClass] object Object to evaluate block against
      # @raise [TimeoutError] if timeout is exceeded
      #

      def while(timeout: nil, message: nil, interval: nil, object: nil)
        timeout ||= Watir.default_timeout
        run_with_timer(timeout, interval) { return unless yield(object) }
        raise TimeoutError, message_for(timeout, object, message)
      end

      private

      def message_for(timeout, object, message)
        message = message.call(object) if message.is_a?(Proc)
        err = "timed out after #{timeout} seconds"
        err << ", #{message}" if message

        err
      end

      def run_with_timer(timeout, interval)
        if timeout.zero?
          yield
        else
          timer.wait(timeout) do
            yield
            sleep interval || INTERVAL
          end
        end
      end
    end # self
  end # Wait

  module Waitable
    #
    # Waits until the condition is true.
    #
    # @example
    #   browser.wait_until(timeout: 2) do |browser|
    #     browser.windows.size == 1
    #   end
    #
    # @example
    #   browser.text_field(name: "new_user_first_name").wait_until(&:present?).click
    #   browser.text_field(name: "new_user_first_name").wait_until(message: 'foo') { |field| field.present? }
    #   browser.text_field(name: "new_user_first_name").wait_until(timeout: 60, &:present?)
    #   browser.text_field(name: "new_user_first_name").wait_until(timeout: 60, name: 'new_user_first_name')
    #
    # @param [Integer] timeout seconds to wait before timing out
    # @param [String] message error message for when times out
    #

    def wait_until(timeout: nil, message: nil, interval: nil, **opt, &blk)
      message ||= proc { |obj| "waiting for true condition on #{obj.inspect}" }

      # TODO: Consider throwing argument error for mixing block & options
      proc = create_proc(opt, &blk)

      Wait.until(timeout: timeout, message: message, interval: interval, object: self, &proc)

      self
    end

    #
    # Waits while the condition is true.
    #
    # @example
    #   browser.wait_while(timeout: 2) do |browser|
    #     !browser.exists?
    #   end
    #   browser.wait_while(timeout: 2, title: 'No')
    #
    # @todo add element example
    #
    # @param [Integer] timeout seconds to wait before timing out
    # @param [String] message error message for when times out
    #

    def wait_while(timeout: nil, message: nil, interval: nil, **opt, &blk)
      message ||= proc { |obj| "waiting for false condition on #{obj.inspect}" }

      # TODO: Consider throwing argument error for mixing block & options
      proc = create_proc(opt, &blk)

      Wait.while(timeout: timeout, message: message, interval: interval, object: self, &proc)

      self
    end

    private

    def create_proc(opt)
      proc do
        reset! if opt.delete(:element_reset) && is_a?(Element)
        (opt.empty? || match_attributes(opt).call) && (!block_given? || yield(self))
      end
    end

    def match_attributes(opt)
      proc do
        opt.keys.all? do |key|
          expected = opt[key]
          actual = if is_a?(Element) && !respond_to?(key)
                     attribute_value(key)
                   else
                     send(key)
                   end
          case expected
          when Regexp
            expected =~ actual
          when Numeric
            expected == actual
          else
            expected.to_s == actual
          end
        end
      end
    end
  end # Waitable
end # Watir