gistfile1.rb

class ListingWindow
  SKIP_N_PERIODS = {
    "exclusive" => 1,
    "pickable" => 2
  }
  
  WINDOW_TIMES = [9,18]
  
  LISTING_TIME_ZONE = "Pacific Time (US & Canada)"
  #LISTING_TIME_ZONE = "UTC"
  
  def self.time_now
    #Time.parse("April 5 2011 18:01 PDT")
    Time.now.in_time_zone(LISTING_TIME_ZONE)
  end
  
  # takes hour as a 24 hour clock
  def self.next_window(time = nil)
    time ||= time_now
    time = time.in_time_zone(LISTING_TIME_ZONE)
    # Calculate next window based on time supplied
    # => 1. Map Window Times array from hours to actual time values based on the day supplied
    # => 2. Select the time that is greater than time supplied and take the first occurance (=next window)
    windows = WINDOW_TIMES.map{|h| Time.new(time.year,time.month,time.day, h, 0, 0, time.utc_offset) }
    window = windows.select{|t| t > time }.first
    
    # => 3. If past the final window value (nil), default to the first window of the following day
    time = time + 1.day
    window ||= Time.new(time.year,time.month,time.day, WINDOW_TIMES[0], 0, 0, time.utc_offset)
    window
  end
  
  def self.next_state_window(state,first_staged_at = nil)
    n = SKIP_N_PERIODS[state.to_s]
    window = next_window(first_staged_at)
    n.times do |i|
      window = next_window(window)
    end
    window
  end
  
  def self.next_exclusive_window(first_staged_at = nil)
    next_state_window("exclusive",first_staged_at)
  end
  
  def self.next_pickable_window(first_staged_at = nil)
    next_state_window("pickable",first_staged_at)
  end

end

# 
# 
# def self.next_window(time = nil)
#   if time
#     time = time.in_time_zone(LISTING_TIME_ZONE)
#   else
#     time = time_now
#   end
#   
#   
#