class Rufus::CronLine

def initialize (line)
  super()
  @original = line
  items = line.split
  unless [ 5, 6 ].include?(items.length)
    raise \
      "cron '#{line}' string should hold 5 or 6 items, " +
      "not #{items.length}" \
  end
  offset = items.length - 5
  @seconds = if offset == 1
    parse_item(items[0], 0, 59)
  else
    [ 0 ]
  end
  @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])
  #adjust_arrays()
end

def matches? (time)
#def matches? (time, precision)
  time = Time.at(time) unless time.kind_of?(Time)
  return false \
    if no_match?(time.sec, @seconds)
    #if precision <= 1 and no_match?(time.sec, @seconds)
  return false \
    if no_match?(time.min, @minutes)
    #if precision <= 60 and no_match?(time.min, @minutes)
  return false \
    if no_match?(time.hour, @hours)
  return false \
    if no_match?(time.day, @days)
  return false \
    if no_match?(time.month, @months)
  return false \
    if no_match?(time.wday, @weekdays)
  true
end

def next_time (now = Time.now)
  #
  # position now to the next cron second
  if @seconds
    next_sec = @seconds.find { |s| s > now.sec } || 60 + @seconds.first
    now += next_sec - now.sec
  else
    now += 1
  end
  #
  # prepare sec jump array
  sjarray = nil
  if @seconds
    sjarray = []
    i = @seconds.index(now.sec)
    ii = i
    loop do
      cur = @seconds[ii]
      ii += 1
      ii = 0 if ii == @seconds.size
      nxt = @seconds[ii]
      nxt += 60 if ii == 0
      sjarray << (nxt - cur)
      break if ii == i
    end
  else
    sjarray = [ 1 ]
  end
  #
  # ok, seek...
  i = 0
  loop do
    return now if matches?(now)
    now += sjarray[i]
    i += 1
    i = 0 if i == sjarray.size
    # danger... potentially no exit...
  end
  nil
end

def no_match? (value, cron_values)
  return false if not cron_values
  cron_values.each do |v|
    return false if value == v # ok, it matches
  end
  true # no match found
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)
  items = item.split(",")
  items.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 = 1
  inc = Integer(item[j+1..-1]) if j
  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 do |day, index|
    item = item.gsub day, "#{index}"
  end
  r = parse_item item, 0, 7
  return r unless r.is_a?(Array)
  r.collect { |e| e == 7 ? 0 : e }.uniq
end

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