require 'rubygems'
require 'bundler/setup'

require 'icalendar'
require 'open-uri'
require 'json'

class SublabCalendar

  URL = "https://sublab.org:5232/calendars/events"

  Event = Struct.new(:summary, :start, :end) do
    def to_json(*args)
      to_h.to_json(*args)
    end
  end

  attr_reader :calendar

  def initialize(ical)
    @calendar = Icalendar.parse(ical).first
  end

  def self.load(url=URL)
    ical = open(url, {ssl_verify_mode: OpenSSL::SSL::VERIFY_NONE})
    new(ical)
  end

  def events
    calendar.events.map(&method(:readable))
  end

  def future
    calendar.events.select {|ev| ev.dtstart >= DateTime.now}.map(&method(:readable))
  end

  def past
    calendar.events.select {|ev| ev.dtstart < DateTime.now}.map(&method(:readable))
  end

  def next(count=1)
    future.take(count)
  end

  def readable(event)
    Event.new(event.summary, event.dtstart.to_s, event.dtend.to_s)
  end

end