class Rufus::CronLine

def date_match?(date)
  return false unless sub_match?(date.day, @days)
  return false unless sub_match?(date.month, @months)
  return false unless sub_match?(date.wday, @weekdays)
  true
end

def initialize (line)
  super()
  @original = line
  items = line.split
  unless items.length == 5 or items.length == 6
    raise(
      "cron '#{line}' string should hold 5 or 6 items, not #{items.length}")
  end
  offset = items.length - 5
  @seconds = offset == 1 ? parse_item(items[0], 0, 59) : [ 0 ]
  @minutes = parse_item(items[0 + offset], 0, 59)
  @hours = parse_item(items[1 + offset], 0, 24)
  @days = parse_item(items[2 + offset], 1, 31)
  @months = parse_item(items[3 + offset], 1, 12)
  @weekdays = parse_weekdays(items[4 + offset])
end

def matches? (time)
  time = Time.at(time) unless time.kind_of?(Time)
  return false unless sub_match?(time.sec, @seconds)
  return false unless sub_match?(time.min, @minutes)
  return false unless sub_match?(time.hour, @hours)
  return false unless sub_match?(time.day, @days)
  return false unless sub_match?(time.month, @months)
  return false unless sub_match?(time.wday, @weekdays)
  true
end

def next_time (time=Time.now)
  time -= time.usec * 1e-6
  time += 1
  loop do
    unless date_match?(time)
      time += (24 - time.hour) * 3600 - time.min * 60 - time.sec
      next
    end
    unless sub_match?(time.hour, @hours)
      time += (60 - time.min) * 60 - time.sec
      next
    end
    unless sub_match?(time.min, @minutes)
      time += 60 - time.sec
      next
    end
    unless sub_match?(time.sec, @seconds)
      time += 1
      next
    end
    break
  end
  time
end

def parse_item (item, min, max)
  return nil if item == '*'
  return parse_list(item, min, max) if item.index(',')
  return parse_range(item, min, max) if item.index('*') or item.index('-')
  i = Integer(item)
  i = min if i < min
  i = max if i > max
  [ i ]
end

def parse_list (item, min, max)
  item.split(',').inject([]) { |r, i|
    r.push(parse_range(i, min, max))
  }.flatten
end

def parse_range (item, min, max)
  i = item.index('-')
  j = item.index('/')
  return item.to_i if (not i and not j)
  inc = j ? Integer(item[j+1..-1]) : 1
  istart = -1
  iend = -1
  if i
    istart = Integer(item[0..i - 1])
    if j
      iend = Integer(item[i + 1..j])
    else
      iend = Integer(item[i + 1..-1])
    end
  else # case */x
    istart = min
    iend = max
  end
  istart = min if istart < min
  iend = max if iend > max
  result = []
  value = istart
  loop do
    result << value
    value = value + inc
    break if value > iend
  end
  result
end

def parse_weekdays (item)
  item = item.downcase
  WDS.each_with_index { |day, index| item = item.gsub(day, index.to_s) }
  r = parse_item(item, 0, 7)
  r.is_a?(Array) ?
    r.collect { |e| e == 7 ? 0 : e }.uniq :
    r
end

def sub_match?(value, values)
  values.nil? || values.include?(value)
end

def to_array
  [ @seconds, @minutes, @hours, @days, @months, @weekdays ]
end