class Chronic::RepeaterDayPortion < Chronic::Repeater #:nodoc:
  @@morning = (6 * 60 * 60)..(12 * 60 * 60) # 6am-12am
  @@afternoon = (13 * 60 * 60)..(17 * 60 * 60) # 1pm-5pm
  @@evening = (17 * 60 * 60)..(20 * 60 * 60) # 5pm-8pm
  @@night = (20 * 60 * 60)..(24 * 60 * 60) # 8pm-12pm

  def initialize(type)
    super
    @current_span = nil

    if type.kind_of? Integer
      @range = (@type * 60 * 60)..((@type + 12) * 60 * 60)
    else
      lookup = {:am => 0..(12 * 60 * 60 - 1),
                :pm => (12 * 60 * 60)..(24 * 60 * 60 - 1),
                :morning => @@morning,
                :afternoon => @@afternoon,
                :evening => @@evening,
                :night => @@night}
      @range = lookup[type]
      lookup[type] || raise("Invalid type '#{type}' for RepeaterDayPortion")
    end
    @range || raise("Range should have been set by now")
  end

  def next(pointer)
    super

    full_day = 60 * 60 * 24

    if !@current_span
      now_seconds = @now - Time.construct(@now.year, @now.month, @now.day)
      if now_seconds < @range.begin
        case pointer
        when :future
          range_start = Time.construct(@now.year, @now.month, @now.day) + @range.begin
        when :past
          range_start = Time.construct(@now.year, @now.month, @now.day) - full_day + @range.begin
        end
      elsif now_seconds > @range.end
        case pointer
        when :future
          range_start = Time.construct(@now.year, @now.month, @now.day) + full_day + @range.begin
        when :past
          range_start = Time.construct(@now.year, @now.month, @now.day) + @range.begin
        end
      else
        case pointer
        when :future
          range_start = Time.construct(@now.year, @now.month, @now.day) + full_day + @range.begin
        when :past
          range_start = Time.construct(@now.year, @now.month, @now.day) - full_day + @range.begin
        end
      end

      @current_span = Chronic::Span.new(range_start, range_start + (@range.end - @range.begin))
    else
      case pointer
      when :future
        @current_span += full_day
      when :past
        @current_span -= full_day
      end
    end
  end

  def this(context = :future)
    super

    range_start = Time.construct(@now.year, @now.month, @now.day) + @range.begin
    @current_span = Chronic::Span.new(range_start, range_start + (@range.end - @range.begin))
  end

  def offset(span, amount, pointer)
    @now = span.begin
    portion_span = self.next(pointer)
    direction = pointer == :future ? 1 : -1
    portion_span + (direction * (amount - 1) * Chronic::RepeaterDay::DAY_SECONDS)
  end

  def width
    @range || raise("Range has not been set")
    return @current_span.width if @current_span
    if @type.kind_of? Integer
      return (12 * 60 * 60)
    else
      @range.end - @range.begin
    end
  end

  def to_s
    super << '-dayportion-' << @type.to_s
  end
end