class Chronic::RepeaterWeekend

def initialize(type)
  super
  @current_week_start = nil
end

def next(pointer)
  super
  if !@current_week_start
    case pointer
    when :future
      saturday_repeater = RepeaterDayName.new(:saturday)
      saturday_repeater.start = @now
      next_saturday_span = saturday_repeater.next(:future)
      @current_week_start = next_saturday_span.begin
    when :past
      saturday_repeater = RepeaterDayName.new(:saturday)
      saturday_repeater.start = (@now + RepeaterDay::DAY_SECONDS)
      last_saturday_span = saturday_repeater.next(:past)
      @current_week_start = last_saturday_span.begin
    end
  else
    direction = pointer == :future ? 1 : -1
    @current_week_start += direction * RepeaterWeek::WEEK_SECONDS
  end
  Span.new(@current_week_start, @current_week_start + WEEKEND_SECONDS)
end

def offset(span, amount, pointer)
  direction = pointer == :future ? 1 : -1
  weekend = RepeaterWeekend.new(:weekend)
  weekend.start = span.begin
  start = weekend.next(pointer).begin + (amount - 1) * direction * RepeaterWeek::WEEK_SECONDS
  Span.new(start, start + (span.end - span.begin))
end

def this(pointer = :future)
  super
  case pointer
  when :future, :none
    saturday_repeater = RepeaterDayName.new(:saturday)
    saturday_repeater.start = @now
    this_saturday_span = saturday_repeater.this(:future)
    Span.new(this_saturday_span.begin, this_saturday_span.begin + WEEKEND_SECONDS)
  when :past
    saturday_repeater = RepeaterDayName.new(:saturday)
    saturday_repeater.start = @now
    last_saturday_span = saturday_repeater.this(:past)
    Span.new(last_saturday_span.begin, last_saturday_span.begin + WEEKEND_SECONDS)
  end
end

def to_s
  super << '-weekend'
end

def width
  WEEKEND_SECONDS
end