module Hermes
  # A few actions built on top of Capybara.
  module Actions

    POSTFIXES = {
      :year   => '1i',
      :month  => '2i',
      :day    => '3i',
      :hour   => '4i',
      :minute => '5i'
    }.freeze

    def select_datetime(datetime, options={})
      select_prefix = select_prefix_from_options(options)

      select_time(datetime, :id_prefix => select_prefix)
      select_date(datetime, :id_prefix => select_prefix)
    end

    def select_time(time, options={})
      select_prefix = select_prefix_from_options(options)

      find_and_select_option(select_prefix,
                             POSTFIXES[:hour],
                             string_with_double_digits(time.hour))

      find_and_select_option(select_prefix,
                             POSTFIXES[:minute],
                             string_with_double_digits(time.min))
    end

    def select_date(date, options={})
      select_prefix = select_prefix_from_options(options)

      find_and_select_option(select_prefix,
                             POSTFIXES[:year],
                             date.year)

      find_and_select_option(select_prefix,
                             POSTFIXES[:month],
                             date.month)

      find_and_select_option(select_prefix,
                             POSTFIXES[:day],
                             string_with_double_digits(date.day))
    end

    private

    def find_and_select_option(select_prefix, postfix, value)
      no_select_msg = "cannot select option, no select box with id prefix '#{select_prefix}' found"
      no_option_msg = "cannot select option, no option with text '#{value}' in select box '#{select_prefix}'"

      select = find(:css, "##{select_prefix}_#{postfix}", :message => no_select_msg)
      select.find(:xpath, ".//option[contains(./@value, '#{value}')]", :message => no_option_msg).select_option
    end

    def string_with_double_digits(number)
      "%.2d" % number
    end

    def select_prefix_from_options(options)
      if options.slice(:id_prefix, :from).values.blank?
        raise(ArgumentError, 'You must supply either :from or :id_prefix option')
      end

      select_prefix   = options[:id_prefix]
      select_prefix ||= find_prefix_by_label(options[:from])

      select_prefix
    end

    def find_prefix_by_label(label)
      message = "cannot select option, select with label '#{label}' not found"
      find(:xpath,
           "//label[contains(normalize-space(string(.)), '#{label}')]/@for",
           :message => message
          ).text
    end
  end
end