calendar helper

gistfile1.rb

# taken from http://railscasts.com/episodes/213-calendars-revised

module CalendarHelper
  def calendar(date = Date.today, type = :list, &block)
    Calendar.new(self, date, type, block).table
  end

  class Calendar < Struct.new(:view, :date, :type, :callback)
    HEADER = %w[Man Tir Ons Tor Fre Lør Søn]
    START_DAY = :monday

    delegate :content_tag, to: :view

    def table
      content_tag calendar_tag_for_type, class: "calendar-list" do
        type.to_sym == :list ? header + whole_month_in_weeks : header_rows + week_rows
      end
    end

  private

    def header
      HEADER.map { |day| content_tag :li, day, class: header_classes }.join.html_safe
    end

    def header_rows
      content_tag :tr do
        HEADER.map { |day| content_tag :th, day }.join.html_safe
      end
    end

    def whole_month_in_weeks
      weeks.map { |day| day_cell(day) }.join.html_safe
    end

    def week_rows
      weeks.map do |week|
        content_tag :tr do
          week.map { |day| day_cell(day) }.join.html_safe
        end
      end.join.html_safe
    end

    def day_cell(day)
      content_tag day_tag_for_type, view.capture(day, &callback), class: day_classes(day)
    end

    def weeks
      first = date.beginning_of_month.beginning_of_week(START_DAY)
      last = date.end_of_month.end_of_week(START_DAY)
      weeks = (first..last).to_a
      type.to_sym == :list ? weeks : weeks.in_groups_of(7)
    end

    def header_classes
      classes = []
      classes << "calendar-list-item"
      classes.empty? ? nil : classes.join(" ")
    end

    def day_classes(day)
      classes = ["day", "calendar-list-item"]
      classes << "current-day" if day == Date.today
      classes << "weekend" if weekend?(day)
      classes << "other-month" if day.month != date.month
      classes.empty? ? nil : classes.join(" ")
    end

    def weekend?(day)
      day.saturday? || day.sunday?
    end

    def calendar_tag_for_type
      type.to_sym == :list ? :ul : :table
    end

    def day_tag_for_type
      type.to_sym == :list ? :li : :th
    end
  end
end